REVERT ME. Add unlink test and a bunch of debug printlns

Attempt to fix list_rels & list_nonrels for dropped segments
Rename put_unlink() to drop_relish() in Timeline trait.
2026-06-18 04:40:37 +00:00 · 2021-09-02 17:29:29 +03:00 · 2021-09-02 16:46:11 +03:00 · 2021-09-02 16:37:05 +03:00 · 2021-09-02 16:33:47 +03:00 · 2021-09-02 16:33:30 +03:00
112 changed files with 2791 additions and 6786 deletions
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -128,14 +128,6 @@ jobs:
            - ~/.cargo/git
            - target

-        # Run style checks
-        # has to run separately from cargo fmt section
-        # since needs to run with dependencies
-      - run:
-          name: clippy
-          command: |
-            ./run_clippy.sh
-
        # Run rust unit tests
      - run: cargo test

@@ -201,9 +193,6 @@ jobs:
      needs_postgres_source:
        type: boolean
        default: false
-      run_in_parallel:
-        type: boolean
-        default: true
    steps:
      - attach_workspace:
          at: /tmp/zenith
@@ -232,9 +221,6 @@ jobs:
              echo "test_selection must be set"
              exit 1
            fi
-            if << parameters.run_in_parallel >>; then
-              EXTRA_PARAMS="-n16 $EXTRA_PARAMS"
-            fi;
            # Run the tests.
            #
            # The junit.xml file allows CircleCI to display more fine-grained test information
@@ -244,8 +230,7 @@ jobs:
            # --verbose prints name of each test (helpful when there are
            # multiple tests in one file)
            # -rA prints summary in the end
-            # -n4 uses four processes to run tests via pytest-xdist
-            pipenv run pytest --junitxml=$TEST_OUTPUT/junit.xml --tb=short --verbose -rA $TEST_SELECTION $EXTRA_PARAMS
+            pipenv run pytest --junitxml=$TEST_OUTPUT/junit.xml --tb=short -s --verbose -rA $TEST_SELECTION $EXTRA_PARAMS
      - run:
          # CircleCI artifacts are preserved one file at a time, so skipping
          # this step isn't a good idea. If you want to extract the
@@ -254,7 +239,7 @@ jobs:
          when: always
          command: |
            du -sh /tmp/test_output/*
-            find /tmp/test_output -type f ! -name "pg.log" ! -name "pageserver.log" ! -name "wal_acceptor.log" ! -name "regression.diffs" ! -name "junit.xml" ! -name "*.filediff" ! -name "*.stdout" ! -name "*.stderr" -delete
+            find /tmp/test_output -type f ! -name "pg.log" ! -name "pageserver.log" ! -name "wal_acceptor.log" ! -name "regression.diffs" ! -name "junit.xml" -delete
            du -sh /tmp/test_output/*
      - store_artifacts:
          path: /tmp/test_output
@@ -279,51 +264,6 @@ jobs:
            echo $DOCKER_PWD | docker login -u $DOCKER_LOGIN --password-stdin
            docker build -t zenithdb/zenith:latest . && docker push zenithdb/zenith:latest

-  # Trigger a new remote CI job
-  remote-ci-trigger:
-    docker:
-      - image: cimg/base:2021.04
-    parameters:
-      remote_repo:
-        type: string
-    environment:
-      REMOTE_REPO: << parameters.remote_repo >>
-    steps:
-      - run:
-          name: Set PR's status to pending
-          command: |
-            LOCAL_REPO=$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME
-
-            curl -f -X POST \
-            https://api.github.com/repos/$LOCAL_REPO/statuses/$CIRCLE_SHA1 \
-            -H "Accept: application/vnd.github.v3+json" \
-            --user "$CI_ACCESS_TOKEN" \
-            --data \
-              "{
-                \"state\": \"pending\",
-                \"context\": \"zenith-remote-ci\",
-                \"description\": \"[$REMOTE_REPO] Remote CI job is about to start\"
-              }"
-      - run:
-          name: Request a remote CI test
-          command: |
-            LOCAL_REPO=$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME
-
-            curl -f -X POST \
-            https://api.github.com/repos/$REMOTE_REPO/actions/workflows/testing.yml/dispatches \
-            -H "Accept: application/vnd.github.v3+json" \
-            --user "$CI_ACCESS_TOKEN" \
-            --data \
-              "{
-                \"ref\": \"main\",
-                \"inputs\": {
-                  \"ci_job_name\": \"zenith-remote-ci\",
-                  \"commit_hash\": \"$CIRCLE_SHA1\",
-                  \"remote_repo\": \"$LOCAL_REPO\",
-                  \"zenith_image_branch\": \"$CIRCLE_BRANCH\"
-                }
-              }"
-
 workflows:
  build_and_test:
    jobs:
@@ -337,7 +277,7 @@ workflows:
          requires:
            - build-postgres
      - run-pytest:
-          name: pg_regress-tests-<< matrix.build_type >>
+          name: pg_regress tests << matrix.build_type >>
          matrix:
            parameters:
              build_type: ["debug", "release"]
@@ -346,7 +286,7 @@ workflows:
          requires:
            - build-zenith-<< matrix.build_type >>
      - run-pytest:
-          name: other-tests-<< matrix.build_type >>
+          name: other tests << matrix.build_type >>
          matrix:
            parameters:
              build_type: ["debug", "release"]
@@ -357,7 +297,6 @@ workflows:
          name: benchmarks
          build_type: release
          test_selection: performance
-          run_in_parallel: false
          requires:
            - build-zenith-release
      - docker-image:
@@ -369,16 +308,5 @@ workflows:
              only:
                - main
          requires:
-            - pg_regress-tests-release
-            - other-tests-release
-      - remote-ci-trigger:
-          # Context passes credentials for gh api
-          context: CI_ACCESS_TOKEN
-          remote_repo: "zenithdb/console"
-          requires:
-            # XXX: Successful build doesn't mean everything is OK, but
-            # the job to be triggered takes so much time to complete (~22 min)
-            # that it's better not to wait for the commented-out steps
-            - build-zenith-debug
-            # - pg_regress-tests-release
-            # - other-tests-release
+            - pg_regress tests release
+            - other tests release
--- a/.dockerignore
+++ b/.dockerignore
@@ -2,13 +2,12 @@
 **/__pycache__
 **/.pytest_cache

-.git
-target
-tmp_check
-tmp_install
-tmp_check_cli
-test_output
-.vscode
-.zenith
-integration_tests/.zenith
-.mypy_cache
+/target
+/tmp_check
+/tmp_install
+/tmp_check_cli
+/test_output
+/.vscode
+/.zenith
+/integration_tests/.zenith
+/Dockerfile
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -307,26 +307,6 @@ dependencies = [
 "vec_map",
 ]

-[[package]]
-name = "const_format"
-version = "0.2.21"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4556f63e28a78fa5e6f310cfea5647a25636def49a338ab69e33b34a3382057b"
-dependencies = [
- "const_format_proc_macros",
-]
-
-[[package]]
-name = "const_format_proc_macros"
-version = "0.2.21"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "552782506c398da94466b364973b563887e0ca078bf33a76d4163736165e3594"
-dependencies = [
- "proc-macro2",
- "quote",
- "unicode-xid",
-]
-
 [[package]]
 name = "control_plane"
 version = "0.1.0"
@@ -345,7 +325,6 @@ dependencies = [
 "serde",
 "serde_json",
 "tar",
- "thiserror",
 "toml",
 "url",
 "walkeeper",
@@ -1193,13 +1172,11 @@ name = "pageserver"
 version = "0.1.0"
 dependencies = [
 "anyhow",
- "async-trait",
 "bookfile",
 "byteorder",
 "bytes",
 "chrono",
 "clap",
- "const_format",
 "crc32c",
 "daemonize",
 "futures",
@@ -1209,16 +1186,19 @@ dependencies = [
 "lazy_static",
 "log",
 "postgres",
- "postgres-protocol",
- "postgres-types",
+ "postgres-protocol 0.6.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
+ "postgres-types 0.2.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
 "postgres_ffi",
 "rand",
 "regex",
 "routerify",
- "rust-s3",
 "scopeguard",
 "serde",
 "serde_json",
+ "slog",
+ "slog-scope",
+ "slog-stdlog",
+ "slog-term",
 "tar",
 "thiserror",
 "tokio",
@@ -1321,9 +1301,27 @@ dependencies = [
 "fallible-iterator",
 "futures",
 "log",
- "postgres-protocol",
+ "postgres-protocol 0.6.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
 "tokio",
- "tokio-postgres",
+ "tokio-postgres 0.7.1",
+]
+
+[[package]]
+name = "postgres-protocol"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ff3e0f70d32e20923cabf2df02913be7c1842d4c772db8065c00fcfdd1d1bff3"
+dependencies = [
+ "base64 0.13.0",
+ "byteorder",
+ "bytes",
+ "fallible-iterator",
+ "hmac",
+ "md-5",
+ "memchr",
+ "rand",
+ "sha2",
+ "stringprep",
 ]

 [[package]]
@@ -1344,6 +1342,17 @@ dependencies = [
 "stringprep",
 ]

+[[package]]
+name = "postgres-types"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "430f4131e1b7657b0cd9a2b0c3408d77c9a43a042d300b8c77f981dffcc43a2f"
+dependencies = [
+ "bytes",
+ "fallible-iterator",
+ "postgres-protocol 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "postgres-types"
 version = "0.2.1"
@@ -1351,7 +1360,7 @@ source = "git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b
 dependencies = [
 "bytes",
 "fallible-iterator",
- "postgres-protocol",
+ "postgres-protocol 0.6.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
 ]

 [[package]]
@@ -1414,9 +1423,16 @@ dependencies = [
 "lazy_static",
 "memchr",
 "parking_lot",
+ "protobuf",
 "thiserror",
 ]

+[[package]]
+name = "protobuf"
+version = "2.24.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db50e77ae196458ccd3dc58a31ea1a90b0698ab1b7928d89f644c25d72070267"
+
 [[package]]
 name = "proxy"
 version = "0.1.0"
@@ -1427,12 +1443,11 @@ dependencies = [
 "hex",
 "md5",
 "rand",
- "reqwest",
 "rustls",
 "serde",
 "serde_json",
 "tokio",
- "tokio-postgres",
+ "tokio-postgres 0.7.2",
 "zenith_utils",
 ]

@@ -2120,9 +2135,9 @@ checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"

 [[package]]
 name = "tokio"
-version = "1.11.0"
+version = "1.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b4efe6fc2395938c8155973d7be49fe8d03a843726e285e100a8a383cc0154ce"
+checksum = "98c8b05dc14c75ea83d63dd391100353789f5f24b8b3866542a5e85c8be8e985"
 dependencies = [
 "autocfg",
 "bytes",
@@ -2131,6 +2146,7 @@ dependencies = [
 "mio",
 "num_cpus",
 "once_cell",
+ "parking_lot",
 "pin-project-lite",
 "signal-hook-registry",
 "tokio-macros",
@@ -2173,8 +2189,31 @@ dependencies = [
 "percent-encoding",
 "phf",
 "pin-project-lite",
- "postgres-protocol",
- "postgres-types",
+ "postgres-protocol 0.6.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
+ "postgres-types 0.2.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
+ "socket2",
+ "tokio",
+ "tokio-util",
+]
+
+[[package]]
+name = "tokio-postgres"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d2b1383c7e4fb9a09e292c7c6afb7da54418d53b045f1c1fac7a911411a2b8b"
+dependencies = [
+ "async-trait",
+ "byteorder",
+ "bytes",
+ "fallible-iterator",
+ "futures",
+ "log",
+ "parking_lot",
+ "percent-encoding",
+ "phf",
+ "pin-project-lite",
+ "postgres-protocol 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "postgres-types 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "socket2",
 "tokio",
 "tokio-util",
@@ -2347,12 +2386,16 @@ dependencies = [
 "log",
 "pageserver",
 "postgres",
- "postgres-protocol",
+ "postgres-protocol 0.6.1 (git+https://github.com/zenithdb/rust-postgres.git?rev=9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858)",
 "postgres_ffi",
 "regex",
 "rust-s3",
 "serde",
- "serde_json",
+ "slog",
+ "slog-async",
+ "slog-scope",
+ "slog-stdlog",
+ "slog-term",
 "tokio",
 "tokio-stream",
 "walkdir",
@@ -2601,11 +2644,6 @@ dependencies = [
 "rustls-split",
 "serde",
 "serde_json",
- "slog",
- "slog-async",
- "slog-scope",
- "slog-stdlog",
- "slog-term",
 "thiserror",
 "tokio",
 "webpki",
--- a/33
+++ b/33
@@ -11,19 +11,38 @@ WORKDIR /zenith
 COPY ./vendor/postgres vendor/postgres
 COPY ./Makefile Makefile
 RUN make -j $(getconf _NPROCESSORS_ONLN) -s postgres
-RUN rm -rf postgres_install/build
+
+#
+# Calculate cargo dependencies.
+# This will always run, but only generate recipe.json with list of dependencies without
+# installing them.
+#
+FROM zenithdb/build:buster AS cargo-deps-inspect
+WORKDIR /zenith
+COPY . .
+RUN cargo chef prepare --recipe-path /zenith/recipe.json
+
+#
+# Build cargo dependencies.
+# This temp cantainner should be rebuilt only if recipe.json was changed.
+#
+FROM zenithdb/build:buster AS deps-build
+WORKDIR /zenith
+COPY --from=pg-build /zenith/tmp_install/include/postgresql/server tmp_install/include/postgresql/server
+COPY --from=cargo-deps-inspect /usr/local/cargo/bin/cargo-chef /usr/local/cargo/bin/
+COPY --from=cargo-deps-inspect /zenith/recipe.json recipe.json
+RUN ROCKSDB_LIB_DIR=/usr/lib/ cargo chef cook --release --recipe-path recipe.json

 #
 # Build zenith binaries
 #
-# TODO: build cargo deps as separate layer. We used cargo-chef before but that was
-# net time waste in a lot of cases. Copying Cargo.lock with empty lib.rs should do the work.
-#
 FROM zenithdb/build:buster AS build
 WORKDIR /zenith
-COPY --from=pg-build /zenith/tmp_install/include/postgresql/server tmp_install/include/postgresql/server
-
 COPY . .
+# Copy cached dependencies
+COPY --from=pg-build /zenith/tmp_install/include/postgresql/server tmp_install/include/postgresql/server
+COPY --from=deps-build /zenith/target target
+COPY --from=deps-build /usr/local/cargo/ /usr/local/cargo/
 RUN cargo build --release

 #
@@ -32,7 +51,7 @@ RUN cargo build --release
 FROM debian:buster-slim
 WORKDIR /data

-RUN apt-get update && apt-get -yq install libreadline-dev libseccomp-dev openssl ca-certificates && \
+RUN apt-get update && apt-get -yq install librocksdb-dev libseccomp-dev openssl && \
    mkdir zenith_install

 COPY --from=build /zenith/target/release/pageserver /usr/local/bin
--- a/Dockerfile.build
+++ b/Dockerfile.build
@@ -9,7 +9,7 @@ WORKDIR /zenith
 # Install postgres and zenith build dependencies
 # clang is for rocksdb
 RUN apt-get update && apt-get -yq install automake libtool build-essential bison flex libreadline-dev zlib1g-dev libxml2-dev \
-                                          libseccomp-dev pkg-config libssl-dev clang
+                                          libseccomp-dev pkg-config libssl-dev librocksdb-dev clang

 # Install rust tools
-RUN rustup component add clippy && cargo install cargo-audit
+RUN rustup component add clippy && cargo install cargo-chef cargo-audit
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ Zenith substitutes PostgreSQL storage layer and redistributes data across a clus

 A Zenith installation consists of Compute nodes and Storage engine.

-Compute nodes are stateless PostgreSQL nodes, backed by zenith storage.
+Compute nodes are stateles PostgreSQL nodes, backed by zenith storage.

 Zenith storage engine consists of two major components:
 - Pageserver. Scalable storage backend for compute nodes.
@@ -125,19 +125,9 @@ Now we use README files to cover design ideas and overall architecture for each

 To view your `rustdoc` documentation in a browser, try running `cargo doc --no-deps --open`

-### Postgres-specific terms
-
-Due to Zenith's very close relation with PostgreSQL internals, there are numerous specific terms used.
-Same applies to certain spelling: i.e. we use MB to denote 1024 * 1024 bytes, while MiB would be technically more correct, it's inconsistent with what PostgreSQL code and its documentation use.
-
-To get more familiar with this aspect, refer to:
-
- [Zenith glossary](/docs/glossary.md)
- [PostgreSQL glossary](https://www.postgresql.org/docs/13/glossary.html)
- Other PostgreSQL documentation and sources (Zenith fork sources can be found [here](https://github.com/zenithdb/postgres))
-
 ## Join the development

 - Read `CONTRIBUTING.md` to learn about project code style and practices.
+- Use glossary in [/docs/glossary.md](/docs/glossary.md)
 - To get familiar with a source tree layout, use [/docs/sourcetree.md](/docs/sourcetree.md).
 - To learn more about PostgreSQL internals, check http://www.interdb.jp/pg/index.html
--- a/control_plane/Cargo.toml
+++ b/control_plane/Cargo.toml
@@ -16,7 +16,6 @@ toml = "0.5"
 lazy_static = "1.4"
 regex = "1"
 anyhow = "1.0"
-thiserror = "1"
 bytes = "1.0.1"
 nix = "0.20"
 url = "2.2.2"
--- a/control_plane/src/compute.rs
+++ b/control_plane/src/compute.rs
@@ -1,24 +1,22 @@
-use std::collections::BTreeMap;
-use std::fs::{self, File};
+use std::fs::{self, File, OpenOptions};
 use std::io::Write;
 use std::net::SocketAddr;
 use std::net::TcpStream;
 use std::os::unix::fs::PermissionsExt;
-use std::path::PathBuf;
-use std::process::{Command, Stdio};
-use std::str::FromStr;
+use std::process::Command;
 use std::sync::Arc;
 use std::time::Duration;
+use std::{collections::BTreeMap, path::PathBuf};

 use anyhow::{Context, Result};
+use lazy_static::lazy_static;
+use regex::Regex;
 use zenith_utils::connstring::connection_host_port;
-use zenith_utils::lsn::Lsn;
 use zenith_utils::postgres_backend::AuthType;
 use zenith_utils::zid::ZTenantId;
 use zenith_utils::zid::ZTimelineId;

 use crate::local_env::LocalEnv;
-use crate::postgresql_conf::PostgresConf;
 use crate::storage::PageServerNode;

 //
@@ -88,31 +86,40 @@ impl ComputeControlPlane {
        &mut self,
        tenantid: ZTenantId,
        branch_name: &str,
-        port: Option<u16>,
+        config_only: bool,
    ) -> Result<Arc<PostgresNode>> {
        let timeline_id = self
            .pageserver
            .branch_get_by_name(&tenantid, branch_name)?
            .timeline_id;

-        let port = port.unwrap_or_else(|| self.get_port());
        let node = Arc::new(PostgresNode {
            name: branch_name.to_owned(),
-            address: SocketAddr::new("127.0.0.1".parse().unwrap(), port),
+            address: SocketAddr::new("127.0.0.1".parse().unwrap(), self.get_port()),
            env: self.env.clone(),
            pageserver: Arc::clone(&self.pageserver),
            is_test: false,
            timelineid: timeline_id,
            tenantid,
-            uses_wal_proposer: false,
        });

-        node.create_pgdata()?;
-        node.setup_pg_conf(self.env.auth_type)?;
-
+        node.init_from_page_server(self.env.auth_type, config_only)?;
        self.nodes
            .insert((tenantid, node.name.clone()), Arc::clone(&node));

+        // Configure the node to stream WAL directly to the pageserver
+        node.append_conf(
+            "postgresql.conf",
+            format!(
+                concat!(
+                    "synchronous_standby_names = 'pageserver'\n", // TODO: add a new function arg?
+                    "zenith.callmemaybe_connstring = '{}'\n",     // FIXME escaping
+                ),
+                node.connstr(),
+            )
+            .as_str(),
+        )?;
+
        Ok(node)
    }
 }
@@ -128,7 +135,6 @@ pub struct PostgresNode {
    is_test: bool,
    pub timelineid: ZTimelineId,
    pub tenantid: ZTenantId,
-    uses_wal_proposer: bool,
 }

 impl PostgresNode {
@@ -144,25 +150,74 @@ impl PostgresNode {
            );
        }

+        lazy_static! {
+            static ref CONF_PORT_RE: Regex = Regex::new(r"(?m)^\s*port\s*=\s*(\d+)\s*$").unwrap();
+            static ref CONF_TIMELINE_RE: Regex =
+                Regex::new(r"(?m)^\s*zenith.zenith_timeline\s*=\s*'(\w+)'\s*$").unwrap();
+            static ref CONF_TENANT_RE: Regex =
+                Regex::new(r"(?m)^\s*zenith.zenith_tenant\s*=\s*'(\w+)'\s*$").unwrap();
+        }
+
        // parse data directory name
        let fname = entry.file_name();
        let name = fname.to_str().unwrap().to_string();

-        // Read config file into memory
+        // find out tcp port in config file
        let cfg_path = entry.path().join("postgresql.conf");
-        let cfg_path_str = cfg_path.to_string_lossy();
-        let mut conf_file = File::open(&cfg_path)
-            .with_context(|| format!("failed to open config file in {}", cfg_path_str))?;
-        let conf = PostgresConf::read(&mut conf_file)
-            .with_context(|| format!("failed to read config file in {}", cfg_path_str))?;
+        let config = fs::read_to_string(cfg_path.clone()).with_context(|| {
+            format!(
+                "failed to read config file in {}",
+                cfg_path.to_str().unwrap()
+            )
+        })?;

-        // Read a few options from the config file
-        let context = format!("in config file {}", cfg_path_str);
-        let port: u16 = conf.parse_field("port", &context)?;
-        let timelineid: ZTimelineId = conf.parse_field("zenith.zenith_timeline", &context)?;
-        let tenantid: ZTenantId = conf.parse_field("zenith.zenith_tenant", &context)?;
+        // parse port
+        let err_msg = format!(
+            "failed to find port definition in config file {}",
+            cfg_path.to_str().unwrap()
+        );
+        let port: u16 = CONF_PORT_RE
+            .captures(config.as_str())
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 1"))?
+            .iter()
+            .last()
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 2"))?
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 3"))?
+            .as_str()
+            .parse()
+            .with_context(|| err_msg)?;

-        let uses_wal_proposer = conf.get("wal_acceptors").is_some();
+        // parse timeline
+        let err_msg = format!(
+            "failed to find timeline definition in config file {}",
+            cfg_path.to_str().unwrap()
+        );
+        let timelineid: ZTimelineId = CONF_TIMELINE_RE
+            .captures(config.as_str())
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 1"))?
+            .iter()
+            .last()
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 2"))?
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 3"))?
+            .as_str()
+            .parse()
+            .with_context(|| err_msg)?;
+
+        // parse tenant
+        let err_msg = format!(
+            "failed to find tenant definition in config file {}",
+            cfg_path.to_str().unwrap()
+        );
+        let tenantid = CONF_TENANT_RE
+            .captures(config.as_str())
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 1"))?
+            .iter()
+            .last()
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 2"))?
+            .ok_or_else(|| anyhow::Error::msg(err_msg.clone() + " 3"))?
+            .as_str()
+            .parse()
+            .with_context(|| err_msg)?;

        // ok now
        Ok(PostgresNode {
@@ -173,54 +228,15 @@ impl PostgresNode {
            is_test: false,
            timelineid,
            tenantid,
-            uses_wal_proposer,
        })
    }

-    fn sync_walkeepers(&self) -> Result<Lsn> {
-        let pg_path = self.env.pg_bin_dir().join("postgres");
-        let sync_handle = Command::new(pg_path)
-            .arg("--sync-safekeepers")
-            .env_clear()
-            .env("LD_LIBRARY_PATH", self.env.pg_lib_dir().to_str().unwrap())
-            .env("DYLD_LIBRARY_PATH", self.env.pg_lib_dir().to_str().unwrap())
-            .env("PGDATA", self.pgdata().to_str().unwrap())
-            .stdout(Stdio::piped())
-            // Comment this to avoid capturing stderr (useful if command hangs)
-            .stderr(Stdio::piped())
-            .spawn()
-            .expect("postgres --sync-safekeepers failed to start");
-
-        let sync_output = sync_handle
-            .wait_with_output()
-            .expect("postgres --sync-safekeepers failed");
-        if !sync_output.status.success() {
-            anyhow::bail!(
-                "sync-safekeepers failed: '{}'",
-                String::from_utf8_lossy(&sync_output.stderr)
-            );
-        }
-
-        let lsn = Lsn::from_str(std::str::from_utf8(&sync_output.stdout)?.trim())?;
-        println!("Walkeepers synced on {}", lsn);
-        Ok(lsn)
-    }
-
    /// Get basebackup from the pageserver as a tar archive and extract it
    /// to the `self.pgdata()` directory.
-    fn do_basebackup(&self, lsn: Option<Lsn>) -> Result<()> {
-        println!(
-            "Extracting base backup to create postgres instance: path={} port={}",
-            self.pgdata().display(),
-            self.address.port()
-        );
-
-        let sql = if let Some(lsn) = lsn {
-            format!("basebackup {} {} {}", self.tenantid, self.timelineid, lsn)
-        } else {
-            format!("basebackup {} {}", self.tenantid, self.timelineid)
-        };
+    pub fn do_basebackup(&self) -> Result<()> {
+        let pgdata = self.pgdata();

+        let sql = format!("basebackup {} {}", self.tenantid, self.timelineid);
        let mut client = self
            .pageserver
            .page_server_psql_client()
@@ -232,104 +248,99 @@ impl PostgresNode {

        // Read the archive directly from the `CopyOutReader`
        tar::Archive::new(copyreader)
-            .unpack(&self.pgdata())
+            .unpack(&pgdata)
            .with_context(|| "extracting page backup failed")?;

        Ok(())
    }

-    fn create_pgdata(&self) -> Result<()> {
-        fs::create_dir_all(&self.pgdata()).with_context(|| {
-            format!(
-                "could not create data directory {}",
-                self.pgdata().display()
-            )
-        })?;
-        fs::set_permissions(self.pgdata().as_path(), fs::Permissions::from_mode(0o700))
-            .with_context(|| {
+    /// Connect to a pageserver, get basebackup, and untar it to initialize a
+    /// new data directory
+    pub fn init_from_page_server(&self, auth_type: AuthType, config_only: bool) -> Result<()> {
+        let pgdata = self.pgdata();
+
+        println!(
+            "Extracting base backup to create postgres instance: path={} port={}",
+            pgdata.display(),
+            self.address.port()
+        );
+
+        // initialize data directory
+        if self.is_test {
+            fs::remove_dir_all(&pgdata).ok();
+        }
+
+        fs::create_dir_all(&pgdata)
+            .with_context(|| format!("could not create data directory {}", pgdata.display()))?;
+        fs::set_permissions(pgdata.as_path(), fs::Permissions::from_mode(0o700)).with_context(
+            || {
                format!(
                    "could not set permissions in data directory {}",
-                    self.pgdata().display()
+                    pgdata.display()
                )
-            })
-    }
+            },
+        )?;
+
+        if config_only {
+            //Just create an empty config file
+            File::create(self.pgdata().join("postgresql.conf").to_str().unwrap())?;
+        } else {
+            self.do_basebackup()?;
+            fs::create_dir_all(self.pgdata().join("pg_wal"))?;
+            fs::create_dir_all(self.pgdata().join("pg_wal").join("archive_status"))?;
+        }

-    // Connect to a page server, get base backup, and untar it to initialize a
-    // new data directory
-    fn setup_pg_conf(&self, auth_type: AuthType) -> Result<()> {
-        let mut conf = PostgresConf::new();
-        conf.append("max_wal_senders", "10");
        // wal_log_hints is mandatory when running against pageserver (see gh issue#192)
        // TODO: is it possible to check wal_log_hints at pageserver side via XLOG_PARAMETER_CHANGE?
-        conf.append("wal_log_hints", "on");
-        conf.append("max_replication_slots", "10");
-        conf.append("hot_standby", "on");
-        conf.append("shared_buffers", "1MB");
-        conf.append("fsync", "off");
-        conf.append("max_connections", "100");
-        conf.append("wal_sender_timeout", "0");
-        conf.append("wal_level", "replica");
-        conf.append("listen_addresses", &self.address.ip().to_string());
-        conf.append("port", &self.address.port().to_string());
+        self.append_conf(
+            "postgresql.conf",
+            &format!(
+                "max_wal_senders = 10\n\
+                 wal_log_hints = on\n\
+                 max_replication_slots = 10\n\
+                 hot_standby = on\n\
+                 shared_buffers = 1MB\n\
+                 fsync = off\n\
+                 max_connections = 100\n\
+                 wal_sender_timeout = 0\n\
+                 wal_level = replica\n\
+                 listen_addresses = '{address}'\n\
+                 port = {port}\n",
+                address = self.address.ip(),
+                port = self.address.port()
+            ),
+        )?;

        // Never clean up old WAL. TODO: We should use a replication
        // slot or something proper, to prevent the compute node
        // from removing WAL that hasn't been streamed to the safekeeper or
        // page server yet. (gh issue #349)
-        conf.append("wal_keep_size", "10TB");
+        self.append_conf("postgresql.conf", "wal_keep_size='10TB'\n")?;

-        // Configure the node to fetch pages from pageserver
-        let pageserver_connstr = {
-            let (host, port) = connection_host_port(&self.pageserver.pg_connection_config);
-
-            // Set up authentication
-            //
-            // $ZENITH_AUTH_TOKEN will be replaced with value from environment
-            // variable during compute pg startup. It is done this way because
-            // otherwise user will be able to retrieve the value using SHOW
-            // command or pg_settings
-            let password = if let AuthType::ZenithJWT = auth_type {
-                "$ZENITH_AUTH_TOKEN"
-            } else {
-                ""
-            };
-
-            format!("host={} port={} password={}", host, port, password)
-        };
-        conf.append("shared_preload_libraries", "zenith");
-        conf.append_line("");
-        conf.append("zenith.page_server_connstring", &pageserver_connstr);
-        conf.append("zenith.zenith_tenant", &self.tenantid.to_string());
-        conf.append("zenith.zenith_timeline", &self.timelineid.to_string());
-        conf.append_line("");
-
-        // Configure the node to stream WAL directly to the pageserver
-        conf.append("synchronous_standby_names", "pageserver"); // TODO: add a new function arg?
-        conf.append("zenith.callmemaybe_connstring", &self.connstr());
-
-        let mut file = File::create(self.pgdata().join("postgresql.conf"))?;
-        file.write_all(conf.to_string().as_bytes())?;
-
-        Ok(())
-    }
-
-    fn load_basebackup(&self) -> Result<()> {
-        let lsn = if self.uses_wal_proposer {
-            // LSN 0 means that it is bootstrap and we need to download just
-            // latest data from the pageserver. That is a bit clumsy but whole bootstrap
-            // procedure evolves quite actively right now, so let's think about it again
-            // when things would be more stable (TODO).
-            let lsn = self.sync_walkeepers()?;
-            if lsn == Lsn(0) {
-                None
-            } else {
-                Some(lsn)
-            }
+        // set up authentication
+        let password = if let AuthType::ZenithJWT = auth_type {
+            "$ZENITH_AUTH_TOKEN"
        } else {
-            None
+            ""
        };

-        self.do_basebackup(lsn)?;
+        // Configure that node to take pages from pageserver
+        let (host, port) = connection_host_port(&self.pageserver.pg_connection_config);
+        self.append_conf(
+            "postgresql.conf",
+            format!(
+                concat!(
+                    "shared_preload_libraries = zenith\n",
+                    // $ZENITH_AUTH_TOKEN will be replaced with value from environment variable during compute pg startup
+                    // it is done this way because otherwise user will be able to retrieve the value using SHOW command or pg_settings
+                    "zenith.page_server_connstring = 'host={} port={} password={}'\n",
+                    "zenith.zenith_timeline='{}'\n",
+                    "zenith.zenith_tenant='{}'\n",
+                ),
+                host, port, password, self.timelineid, self.tenantid,
+            )
+            .as_str(),
+        )?;

        Ok(())
    }
@@ -351,6 +362,14 @@ impl PostgresNode {
        }
    }

+    pub fn append_conf(&self, config: &str, opts: &str) -> Result<()> {
+        OpenOptions::new()
+            .append(true)
+            .open(self.pgdata().join(config).to_str().unwrap())?
+            .write_all(opts.as_bytes())?;
+        Ok(())
+    }
+
    fn pg_ctl(&self, args: &[&str], auth_token: &Option<String>) -> Result<()> {
        let pg_ctl_path = self.env.pg_bin_dir().join("pg_ctl");
        let mut cmd = Command::new(pg_ctl_path);
@@ -389,22 +408,38 @@ impl PostgresNode {
        }

        // 1. We always start compute node from scratch, so
-        // if old dir exists, preserve 'postgresql.conf' and drop the directory
+        // if old dir exists, preserve config files and drop the directory
+
+        // XXX Now we only use 'postgresql.conf'.
+        // If we will need 'pg_hba.conf', support it here too
+
        let postgresql_conf_path = self.pgdata().join("postgresql.conf");
-        let postgresql_conf = fs::read(&postgresql_conf_path).with_context(|| {
+        let postgresql_conf = fs::read(postgresql_conf_path.clone()).with_context(|| {
            format!(
                "failed to read config file in {}",
                postgresql_conf_path.to_str().unwrap()
            )
        })?;
+
+        println!(
+            "Destroying postgres data directory '{}'",
+            self.pgdata().to_str().unwrap()
+        );
        fs::remove_dir_all(&self.pgdata())?;
-        self.create_pgdata()?;

-        // 2. Bring back config files
-        fs::write(&postgresql_conf_path, postgresql_conf)?;
+        // 2. Create new node
+        self.init_from_page_server(self.env.auth_type, false)?;

-        // 3. Load basebackup
-        self.load_basebackup()?;
+        // 3. Bring back config files
+
+        if let Ok(mut file) = OpenOptions::new()
+            .append(false)
+            .write(true)
+            .open(&postgresql_conf_path)
+        {
+            file.write_all(&postgresql_conf)?;
+            file.sync_all()?;
+        }

        // 4. Finally start the compute node postgres
        println!("Starting postgres node at '{}'", self.connstr());
@@ -416,22 +451,13 @@ impl PostgresNode {
    }

    pub fn stop(&self, destroy: bool) -> Result<()> {
-        // If we are going to destroy data directory,
-        // use immediate shutdown mode, otherwise,
-        // shutdown gracefully to leave the data directory sane.
-        //
-        // Compute node always starts from scratch, so stop
-        // without destroy only used for testing and debugging.
-        //
+        self.pg_ctl(&["-m", "immediate", "stop"], &None)?;
        if destroy {
-            self.pg_ctl(&["-m", "immediate", "stop"], &None)?;
            println!(
                "Destroying postgres data directory '{}'",
                self.pgdata().to_str().unwrap()
            );
            fs::remove_dir_all(&self.pgdata())?;
-        } else {
-            self.pg_ctl(&["stop"], &None)?;
        }
        Ok(())
    }
--- a/control_plane/src/lib.rs
+++ b/control_plane/src/lib.rs
@@ -12,7 +12,6 @@ use std::path::Path;

 pub mod compute;
 pub mod local_env;
-pub mod postgresql_conf;
 pub mod storage;

 /// Read a PID file
--- a/control_plane/src/local_env.rs
+++ b/control_plane/src/local_env.rs
@@ -4,24 +4,27 @@
 // Now it also provides init method which acts like a stub for proper installation
 // script which will use local paths.
 //
-use anyhow::{Context, Result};
+use anyhow::{anyhow, Context, Result};
+use hex;
 use serde::{Deserialize, Serialize};
-use std::env;
 use std::fs;
 use std::path::PathBuf;
 use std::process::{Command, Stdio};
+use std::{collections::BTreeMap, env};
+use url::Url;
 use zenith_utils::auth::{encode_from_key_path, Claims, Scope};
 use zenith_utils::postgres_backend::AuthType;
 use zenith_utils::zid::ZTenantId;

+pub type Remotes = BTreeMap<String, String>;
+
 //
 // This data structures represent deserialized zenith CLI config
 //
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct LocalEnv {
-    // Pageserver connection settings
-    pub pageserver_pg_port: u16,
-    pub pageserver_http_port: u16,
+    // Pageserver connection strings
+    pub pageserver_connstring: String,

    // Base directory for both pageserver and compute nodes
    pub base_data_dir: PathBuf,
@@ -32,8 +35,8 @@ pub struct LocalEnv {
    // to four separate paths and match OS-specific installation layout.
    pub pg_distrib_dir: PathBuf,

-    // Path to pageserver binary.
-    pub zenith_distrib_dir: PathBuf,
+    // Path to pageserver binary. Empty for remote pageserver.
+    pub zenith_distrib_dir: Option<PathBuf>,

    // keeping tenant id in config to reduce copy paste when running zenith locally with single tenant
    #[serde(with = "hex")]
@@ -47,6 +50,8 @@ pub struct LocalEnv {

    // used to issue tokens during e.g pg start
    pub private_key_path: PathBuf,
+
+    pub remotes: Remotes,
 }

 impl LocalEnv {
@@ -59,7 +64,11 @@ impl LocalEnv {
    }

    pub fn pageserver_bin(&self) -> Result<PathBuf> {
-        Ok(self.zenith_distrib_dir.join("pageserver"))
+        Ok(self
+            .zenith_distrib_dir
+            .as_ref()
+            .ok_or_else(|| anyhow!("Can not manage remote pageserver"))?
+            .join("pageserver"))
    }

    pub fn pg_data_dirs_path(&self) -> PathBuf {
@@ -89,8 +98,7 @@ fn base_path() -> PathBuf {
 // Initialize a new Zenith repository
 //
 pub fn init(
-    pageserver_pg_port: u16,
-    pageserver_http_port: u16,
+    remote_pageserver: Option<&str>,
    tenantid: ZTenantId,
    auth_type: AuthType,
 ) -> Result<()> {
@@ -157,22 +165,39 @@ pub fn init(
    let auth_token =
        encode_from_key_path(&Claims::new(None, Scope::PageServerApi), &private_key_path)?;

-    // Find zenith binaries.
-    let zenith_distrib_dir = env::current_exe()?.parent().unwrap().to_owned();
-    if !zenith_distrib_dir.join("pageserver").exists() {
-        anyhow::bail!("Can't find pageserver binary.",);
-    }
+    let conf = if let Some(addr) = remote_pageserver {
+        // check that addr is parsable
+        let _uri = Url::parse(addr).map_err(|e| anyhow!("{}: {}", addr, e))?;

-    let conf = LocalEnv {
-        pageserver_pg_port,
-        pageserver_http_port,
-        pg_distrib_dir,
-        zenith_distrib_dir,
-        base_data_dir: base_path,
-        tenantid,
-        auth_token,
-        auth_type,
-        private_key_path,
+        LocalEnv {
+            pageserver_connstring: format!("postgresql://{}/", addr),
+            pg_distrib_dir,
+            zenith_distrib_dir: None,
+            base_data_dir: base_path,
+            remotes: BTreeMap::default(),
+            tenantid,
+            auth_token,
+            auth_type,
+            private_key_path,
+        }
+    } else {
+        // Find zenith binaries.
+        let zenith_distrib_dir = env::current_exe()?.parent().unwrap().to_owned();
+        if !zenith_distrib_dir.join("pageserver").exists() {
+            anyhow::bail!("Can't find pageserver binary.",);
+        }
+
+        LocalEnv {
+            pageserver_connstring: "postgresql://127.0.0.1:6400".to_string(),
+            pg_distrib_dir,
+            zenith_distrib_dir: Some(zenith_distrib_dir),
+            base_data_dir: base_path,
+            remotes: BTreeMap::default(),
+            tenantid,
+            auth_token,
+            auth_type,
+            private_key_path,
+        }
    };

    fs::create_dir_all(conf.pg_data_dirs_path())?;
@@ -200,3 +225,12 @@ pub fn load_config() -> Result<LocalEnv> {
    let config = fs::read_to_string(repopath.join("config"))?;
    toml::from_str(config.as_str()).map_err(|e| e.into())
 }
+
+// Save config. We use that to change set of remotes from CLI itself.
+pub fn save_config(conf: &LocalEnv) -> Result<()> {
+    let config_path = base_path().join("config");
+    let conf_str = toml::to_string_pretty(conf)?;
+
+    fs::write(config_path, conf_str)?;
+    Ok(())
+}
--- a/control_plane/src/postgresql_conf.rs
+++ b/control_plane/src/postgresql_conf.rs
@@ -1,212 +0,0 @@
-///
-/// Module for parsing postgresql.conf file.
-///
-/// NOTE: This doesn't implement the full, correct postgresql.conf syntax. Just
-/// enough to extract a few settings we need in Zenith, assuming you don't do
-/// funny stuff like include-directives or funny escaping.
-use anyhow::{anyhow, bail, Context, Result};
-use lazy_static::lazy_static;
-use regex::Regex;
-use std::collections::HashMap;
-use std::fmt;
-use std::io::BufRead;
-use std::str::FromStr;
-
-/// In-memory representation of a postgresql.conf file
-#[derive(Default)]
-pub struct PostgresConf {
-    lines: Vec<String>,
-    hash: HashMap<String, String>,
-}
-
-lazy_static! {
-    static ref CONF_LINE_RE: Regex = Regex::new(r"^((?:\w|\.)+)\s*=\s*(\S+)$").unwrap();
-}
-
-impl PostgresConf {
-    pub fn new() -> PostgresConf {
-        PostgresConf::default()
-    }
-
-    /// Read file into memory
-    pub fn read(read: impl std::io::Read) -> Result<PostgresConf> {
-        let mut result = Self::new();
-
-        for line in std::io::BufReader::new(read).lines() {
-            let line = line?;
-
-            // Store each line in a vector, in original format
-            result.lines.push(line.clone());
-
-            // Also parse each line and insert key=value lines into a hash map.
-            //
-            // FIXME: This doesn't match exactly the flex/bison grammar in PostgreSQL.
-            // But it's close enough for our usage.
-            let line = line.trim();
-            if line.starts_with('#') {
-                // comment, ignore
-                continue;
-            } else if let Some(caps) = CONF_LINE_RE.captures(line) {
-                let name = caps.get(1).unwrap().as_str();
-                let raw_val = caps.get(2).unwrap().as_str();
-
-                if let Ok(val) = deescape_str(raw_val) {
-                    // Note: if there's already an entry in the hash map for
-                    // this key, this will replace it. That's the behavior what
-                    // we want; when PostgreSQL reads the file, each line
-                    // overrides any previous value for the same setting.
-                    result.hash.insert(name.to_string(), val.to_string());
-                }
-            }
-        }
-        Ok(result)
-    }
-
-    /// Return the current value of 'option'
-    pub fn get(&self, option: &str) -> Option<&str> {
-        self.hash.get(option).map(|x| x.as_ref())
-    }
-
-    /// Return the current value of a field, parsed to the right datatype.
-    ///
-    /// This calls the FromStr::parse() function on the value of the field. If
-    /// the field does not exist, or parsing fails, returns an error.
-    ///
-    pub fn parse_field<T>(&self, field_name: &str, context: &str) -> Result<T>
-    where
-        T: FromStr,
-        <T as FromStr>::Err: std::error::Error + Send + Sync + 'static,
-    {
-        self.get(field_name)
-            .ok_or_else(|| anyhow!("could not find '{}' option {}", field_name, context))?
-            .parse::<T>()
-            .with_context(|| format!("could not parse '{}' option {}", field_name, context))
-    }
-
-    ///
-    /// Note: if you call this multiple times for the same option, the config
-    /// file will a line for each call. It would be nice to have a function
-    /// to change an existing line, but that's a TODO.
-    ///
-    pub fn append(&mut self, option: &str, value: &str) {
-        self.lines
-            .push(format!("{}={}\n", option, escape_str(value)));
-        self.hash.insert(option.to_string(), value.to_string());
-    }
-
-    /// Append an arbitrary non-setting line to the config file
-    pub fn append_line(&mut self, line: &str) {
-        self.lines.push(line.to_string());
-    }
-}
-
-impl fmt::Display for PostgresConf {
-    /// Return the whole configuration file as a string
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        for line in self.lines.iter() {
-            f.write_str(line)?;
-        }
-        Ok(())
-    }
-}
-
-/// Escape a value for putting in postgresql.conf.
-fn escape_str(s: &str) -> String {
-    // If the string doesn't contain anything that needs quoting or escaping, return it
-    // as it is.
-    //
-    // The first part of the regex, before the '|', matches the INTEGER rule in the
-    // PostgreSQL flex grammar (guc-file.l). It matches plain integers like "123" and
-    // "-123", and also accepts units like "10MB". The second part of the regex matches
-    // the UNQUOTED_STRING rule, and accepts strings that contain a single word, beginning
-    // with a letter. That covers words like "off" or "posix". Everything else is quoted.
-    //
-    // This regex is a bit more conservative than the rules in guc-file.l, so we quote some
-    // strings that PostgreSQL would accept without quoting, but that's OK.
-    lazy_static! {
-        static ref UNQUOTED_RE: Regex =
-            Regex::new(r"(^[-+]?[0-9]+[a-zA-Z]*$)|(^[a-zA-Z][a-zA-Z0-9]*$)").unwrap();
-    }
-    if UNQUOTED_RE.is_match(s) {
-        s.to_string()
-    } else {
-        // Otherwise escape and quote it
-        let s = s
-            .replace('\\', "\\\\")
-            .replace('\n', "\\n")
-            .replace('\'', "''");
-
-        "\'".to_owned() + &s + "\'"
-    }
-}
-
-/// De-escape a possibly-quoted value.
-///
-/// See `DeescapeQuotedString` function in PostgreSQL sources for how PostgreSQL
-/// does this.
-fn deescape_str(s: &str) -> Result<String> {
-    // If the string has a quote at the beginning and end, strip them out.
-    if s.len() >= 2 && s.starts_with('\'') && s.ends_with('\'') {
-        let mut result = String::new();
-
-        let mut iter = s[1..(s.len() - 1)].chars().peekable();
-        while let Some(c) = iter.next() {
-            let newc = if c == '\\' {
-                match iter.next() {
-                    Some('b') => '\x08',
-                    Some('f') => '\x0c',
-                    Some('n') => '\n',
-                    Some('r') => '\r',
-                    Some('t') => '\t',
-                    Some('0'..='7') => {
-                        // TODO
-                        bail!("octal escapes not supported");
-                    }
-                    Some(n) => n,
-                    None => break,
-                }
-            } else if c == '\'' && iter.peek() == Some(&'\'') {
-                // doubled quote becomes just one quote
-                iter.next().unwrap()
-            } else {
-                c
-            };
-
-            result.push(newc);
-        }
-        Ok(result)
-    } else {
-        Ok(s.to_string())
-    }
-}
-
-#[test]
-fn test_postgresql_conf_escapes() -> Result<()> {
-    assert_eq!(escape_str("foo bar"), "'foo bar'");
-    // these don't need to be quoted
-    assert_eq!(escape_str("foo"), "foo");
-    assert_eq!(escape_str("123"), "123");
-    assert_eq!(escape_str("+123"), "+123");
-    assert_eq!(escape_str("-10"), "-10");
-    assert_eq!(escape_str("1foo"), "1foo");
-    assert_eq!(escape_str("foo1"), "foo1");
-    assert_eq!(escape_str("10MB"), "10MB");
-    assert_eq!(escape_str("-10kB"), "-10kB");
-
-    // these need quoting and/or escaping
-    assert_eq!(escape_str("foo bar"), "'foo bar'");
-    assert_eq!(escape_str("fo'o"), "'fo''o'");
-    assert_eq!(escape_str("fo\no"), "'fo\\no'");
-    assert_eq!(escape_str("fo\\o"), "'fo\\\\o'");
-    assert_eq!(escape_str("10 cats"), "'10 cats'");
-
-    // Test de-escaping
-    assert_eq!(deescape_str(&escape_str("foo"))?, "foo");
-    assert_eq!(deescape_str(&escape_str("fo'o\nba\\r"))?, "fo'o\nba\\r");
-    assert_eq!(deescape_str("'\\b\\f\\n\\r\\t'")?, "\x08\x0c\n\r\t");
-
-    // octal-escapes are currently not supported
-    assert!(deescape_str("'foo\\7\\07\\007'").is_err());
-
-    Ok(())
-}
--- a/control_plane/src/storage.rs
+++ b/control_plane/src/storage.rs
@@ -1,19 +1,17 @@
-use std::io::Write;
+use std::collections::HashMap;
 use std::net::TcpStream;
 use std::path::PathBuf;
 use std::process::Command;
+use std::thread;
 use std::time::Duration;
-use std::{io, result, thread};

-use anyhow::{anyhow, bail};
+use anyhow::{anyhow, bail, ensure, Result};
 use nix::sys::signal::{kill, Signal};
 use nix::unistd::Pid;
 use pageserver::http::models::{BranchCreateRequest, TenantCreateRequest};
 use postgres::{Config, NoTls};
-use reqwest::blocking::{Client, RequestBuilder, Response};
-use reqwest::{IntoUrl, Method};
-use thiserror::Error;
-use zenith_utils::http::error::HttpErrorBody;
+use reqwest::blocking::{Client, RequestBuilder};
+use reqwest::{IntoUrl, Method, StatusCode};
 use zenith_utils::postgres_backend::AuthType;
 use zenith_utils::zid::ZTenantId;

@@ -22,38 +20,7 @@ use crate::read_pidfile;
 use pageserver::branches::BranchInfo;
 use zenith_utils::connstring::connection_address;

-#[derive(Error, Debug)]
-pub enum PageserverHttpError {
-    #[error("Reqwest error: {0}")]
-    Transport(#[from] reqwest::Error),
-
-    #[error("Error: {0}")]
-    Response(String),
-}
-
-type Result<T> = result::Result<T, PageserverHttpError>;
-
-pub trait ResponseErrorMessageExt: Sized {
-    fn error_from_body(self) -> Result<Self>;
-}
-
-impl ResponseErrorMessageExt for Response {
-    fn error_from_body(self) -> Result<Self> {
-        let status = self.status();
-        if !(status.is_client_error() || status.is_server_error()) {
-            return Ok(self);
-        }
-
-        // reqwest do not export it's error construction utility functions, so lets craft the message ourselves
-        let url = self.url().to_owned();
-        Err(PageserverHttpError::Response(
-            match self.json::<HttpErrorBody>() {
-                Ok(err_body) => format!("Error: {}", err_body.msg),
-                Err(_) => format!("Http error ({}) at {}.", status.as_u16(), url),
-            },
-        ))
-    }
-}
+const HTTP_BASE_URL: &str = "http://127.0.0.1:9898/v1";

 //
 // Control routines for pageserver.
@@ -79,36 +46,27 @@ impl PageServerNode {

        PageServerNode {
            kill_on_exit: false,
-            pg_connection_config: Self::pageserver_connection_config(
-                password,
-                env.pageserver_pg_port,
-            ),
+            pg_connection_config: Self::default_config(password), // default
            env: env.clone(),
            http_client: Client::new(),
-            http_base_url: format!("http://localhost:{}/v1", env.pageserver_http_port),
+            http_base_url: HTTP_BASE_URL.to_owned(),
        }
    }

-    fn pageserver_connection_config(password: &str, port: u16) -> Config {
-        format!("postgresql://no_user:{}@localhost:{}/no_db", password, port)
+    fn default_config(password: &str) -> Config {
+        format!("postgresql://no_user:{}@localhost:64000/no_db", password)
            .parse()
            .unwrap()
    }

-    pub fn init(&self, create_tenant: Option<&str>, enable_auth: bool) -> anyhow::Result<()> {
+    pub fn init(&self, create_tenant: Option<&str>, enable_auth: bool) -> Result<()> {
        let mut cmd = Command::new(self.env.pageserver_bin()?);
-        let listen_pg = format!("localhost:{}", self.env.pageserver_pg_port);
-        let listen_http = format!("localhost:{}", self.env.pageserver_http_port);
        let mut args = vec![
            "--init",
            "-D",
            self.env.base_data_dir.to_str().unwrap(),
            "--postgres-distrib",
            self.env.pg_distrib_dir.to_str().unwrap(),
-            "--listen-pg",
-            &listen_pg,
-            "--listen-http",
-            &listen_http,
        ];

        if enable_auth {
@@ -116,10 +74,7 @@ impl PageServerNode {
            args.extend(&["--auth-type", "ZenithJWT"]);
        }

-        if let Some(tenantid) = create_tenant {
-            args.extend(&["--create-tenant", tenantid])
-        }
-
+        create_tenant.map(|tenantid| args.extend(&["--create-tenant", tenantid]));
        let status = cmd
            .args(args)
            .env_clear()
@@ -142,13 +97,12 @@ impl PageServerNode {
        self.repo_path().join("pageserver.pid")
    }

-    pub fn start(&self) -> anyhow::Result<()> {
-        print!(
-            "Starting pageserver at '{}' in '{}'",
+    pub fn start(&self) -> Result<()> {
+        println!(
+            "Starting pageserver at '{}' in {}",
            connection_address(&self.pg_connection_config),
            self.repo_path().display()
        );
-        io::stdout().flush().unwrap();

        let mut cmd = Command::new(self.env.pageserver_bin()?);
        cmd.args(&["-D", self.repo_path().to_str().unwrap()])
@@ -165,41 +119,25 @@ impl PageServerNode {

        // It takes a while for the page server to start up. Wait until it is
        // open for business.
-        const RETRIES: i8 = 15;
-        for retries in 1..RETRIES {
+        for retries in 1..15 {
            match self.check_status() {
                Ok(_) => {
-                    println!("\nPageserver started");
+                    println!("Pageserver started");
                    return Ok(());
                }
                Err(err) => {
-                    match err {
-                        PageserverHttpError::Transport(err) => {
-                            if err.is_connect() && retries < 5 {
-                                print!(".");
-                                io::stdout().flush().unwrap();
-                            } else {
-                                if retries == 5 {
-                                    println!() // put a line break after dots for second message
-                                }
-                                println!(
-                                    "Pageserver not responding yet, err {} retrying ({})...",
-                                    err, retries
-                                );
-                            }
-                        }
-                        PageserverHttpError::Response(msg) => {
-                            bail!("pageserver failed to start: {} ", msg)
-                        }
-                    }
+                    println!(
+                        "Pageserver not responding yet, err {} retrying ({})...",
+                        err, retries
+                    );
                    thread::sleep(Duration::from_secs(1));
                }
            }
        }
-        bail!("pageserver failed to start in {} seconds", RETRIES);
+        bail!("pageserver failed to start");
    }

-    pub fn stop(&self) -> anyhow::Result<()> {
+    pub fn stop(&self) -> Result<()> {
        let pid = read_pidfile(&self.pid_file())?;
        let pid = Pid::from_raw(pid);
        if kill(pid, Signal::SIGTERM).is_err() {
@@ -228,7 +166,7 @@ impl PageServerNode {
        client.simple_query(sql).unwrap()
    }

-    pub fn page_server_psql_client(&self) -> result::Result<postgres::Client, postgres::Error> {
+    pub fn page_server_psql_client(&self) -> Result<postgres::Client, postgres::Error> {
        self.pg_connection_config.connect(NoTls)
    }

@@ -241,9 +179,14 @@ impl PageServerNode {
    }

    pub fn check_status(&self) -> Result<()> {
-        self.http_request(Method::GET, format!("{}/{}", self.http_base_url, "status"))
+        let status = self
+            .http_request(Method::GET, format!("{}/{}", self.http_base_url, "status"))
            .send()?
-            .error_from_body()?;
+            .status();
+        ensure!(
+            status == StatusCode::OK,
+            format!("got unexpected response status {}", status)
+        );
        Ok(())
    }

@@ -251,7 +194,7 @@ impl PageServerNode {
        Ok(self
            .http_request(Method::GET, format!("{}/{}", self.http_base_url, "tenant"))
            .send()?
-            .error_from_body()?
+            .error_for_status()?
            .json()?)
    }

@@ -262,7 +205,7 @@ impl PageServerNode {
                tenant_id: tenantid,
            })
            .send()?
-            .error_from_body()?
+            .error_for_status()?
            .json()?)
    }

@@ -273,7 +216,7 @@ impl PageServerNode {
                format!("{}/branch/{}", self.http_base_url, tenantid),
            )
            .send()?
-            .error_from_body()?
+            .error_for_status()?
            .json()?)
    }

@@ -284,30 +227,35 @@ impl PageServerNode {
        tenantid: &ZTenantId,
    ) -> Result<BranchInfo> {
        Ok(self
-            .http_request(Method::POST, format!("{}/branch", self.http_base_url))
+            .http_request(Method::POST, format!("{}/{}", self.http_base_url, "branch"))
            .json(&BranchCreateRequest {
                tenant_id: tenantid.to_owned(),
                name: branch_name.to_owned(),
                start_point: startpoint.to_owned(),
            })
            .send()?
-            .error_from_body()?
+            .error_for_status()?
            .json()?)
    }

+    // TODO: make this a separate request type and avoid loading all the branches
    pub fn branch_get_by_name(
        &self,
        tenantid: &ZTenantId,
        branch_name: &str,
    ) -> Result<BranchInfo> {
-        Ok(self
-            .http_request(
-                Method::GET,
-                format!("{}/branch/{}/{}", self.http_base_url, tenantid, branch_name),
-            )
-            .send()?
-            .error_for_status()?
-            .json()?)
+        let branch_infos = self.branch_list(tenantid)?;
+        let branch_by_name: Result<HashMap<String, BranchInfo>> = branch_infos
+            .into_iter()
+            .map(|branch_info| Ok((branch_info.name.clone(), branch_info)))
+            .collect();
+        let branch_by_name = branch_by_name?;
+
+        let branch = branch_by_name
+            .get(branch_name)
+            .ok_or_else(|| anyhow!("Branch {} not found", branch_name))?;
+
+        Ok(branch.clone())
    }
 }

--- a/docs/README.md
+++ b/docs/README.md
@@ -11,4 +11,3 @@
 - [postgres_ffi/README](/postgres_ffi/README) — Postgres FFI overview.
 - [test_runner/README.md](/test_runner/README.md) — tests infrastructure overview.
 - [walkeeper/README](/walkeeper/README.md) — WAL service overview.
- [core_changes.md](core_changes.md) - Description of Zenith changes in Postgres core
--- a/docs/core_changes.md
+++ b/docs/core_changes.md
@@ -1,202 +0,0 @@
-1. Add t_cid to XLOG record
- Why?
-  The cmin/cmax on a heap page is a real bummer. I don't see any other way to fix that than bite the bullet and modify the WAL-logging routine to include the cmin/cmax.
-
-  To recap, the problem is that the XLOG_HEAP_INSERT record does not include the command id of the inserted row. And same with deletion/update. So in the primary, a row is inserted with current xmin + cmin. But in the replica, the cmin is always set to 1. That works, because the command id is only relevant to the inserting transaction itself. After commit/abort, no one cares abut it anymore.
-
- Alternatives?
-  I don't know
-
-2. Add PD_WAL_LOGGED.
- Why?
-  Postgres sometimes writes data to the page before it is wal-logged. If such page ais swapped out, we  will loose this change. The problem is currently solved by setting PD_WAL_LOGGED bit in page header. When page without this bit set is written to the SMGR, then it is forced to be written to the WAL as FPI using log_newpage_copy() function.
-
-  There was wrong assumption that it can happen only during construction of some exotic indexes (like gist). It is not true. The same situation can happen with COPY,VACUUM and when record hint bits are set.
-
- Discussion:
-  https://discord.com/channels/869525774699462656/882681420986851359
-
- Alternatives:
-  Do not store this flag in page header, but associate this bit with shared buffer. Logically it is more correct but in practice we will get not advantages: neither in space, neither in CPU overhead.
-
-
-3. XLogReadBufferForRedo not always loads and pins requested buffer. So we need to add extra checks that buffer is really pinned. Also do not use BufferGetBlockNumber for buffer returned by XLogReadBufferForRedo.
- Why?
-  XLogReadBufferForRedo is not pinning pages which are not requested by wal-redo. It is specific only for wal-redo Postgres.
-
- Alternatives?
-  No
-
-
-4. Eliminate reporting of some warnings related with hint bits, for example
-"page is not marked all-visible but visibility map bit is set in relation".
- Why?
-  Hint bit may be not WAL logged.
-
- Alternative?
-  Always wal log any page changes.
-
-
-5. Maintain last written LSN.
- Why?
-  When compute node requests page from page server, we need to specify LSN. Ideally it should be LSN
-  of WAL record performing last update of this pages. But we do not know it, because we do not have page.
-  We can use current WAL flush position, but in this case there is high probability that page server
-  will be blocked until this peace of WAL is delivered.
-  As better approximation we can keep max LSN of written page. It will be better to take in account LSNs only of evicted pages,
-  but SMGR API doesn't provide such knowledge.
-
- Alternatives?
-  Maintain map of LSNs of evicted pages.
-
-
-6. Launching Postgres without WAL.
- Why?
-  According to Zenith architecture compute node is stateless. So when we are launching
-  compute node, we need to provide some dummy PG_DATADIR. Relation pages
-  can be requested on demand from page server. But Postgres still need some non-relational data:
-  control and configuration files, SLRUs,...
-  It is currently implemented  using basebackup (do not mix with pg_basebackup) which is created
-  by pageserver. It includes in this tarball config/control files, SLRUs and required directories.
-  As far as pageserver do not have original (non-scattered) WAL segments, it includes in
-  this tarball dummy WAL segment which contains only SHUTDOWN_CHECKPOINT record at the beginning of segment,
-  which redo field points to the end of wal. It allows to load checkpoint record in more or less
-  standard way with minimal changes of Postgres, but then some special handling is needed,
-  including restoring previous record position from zenith.signal file.
-  Also we have to correctly initialize header of last WAL page (pointed by checkpoint.redo)
-  to pass checks performed by XLogReader.
-
- Alternatives?
-  We may not include fake WAL segment in tarball at all and modify xlog.c to load checkpoint record
-  in special way. But it may only increase number of changes in xlog.c
-
-7. Add redo_read_buffer_filter callback to XLogReadBufferForRedoExtended
- Why?
-  We need a way in wal-redo Postgres to ignore pages which are not requested by pageserver.
-  So wal-redo Postgres reconstructs only requested page and for all other returns BLK_DONE
-  which means that recovery for them is not needed.
-
- Alternatives?
-  No
-
-8. Enforce WAL logging of sequence updates.
- Why?
-  Due to performance reasons Postgres don't want to log each fetching of a value from a sequence,
-  so we pre-log a few fetches in advance. In the event of crash we can lose
-  (skip over) as many values as we pre-logged.
-  But it doesn't work with Zenith because page with sequence value can be evicted from buffer cache
-  and we will get a gap in sequence values even without crash.
-
- Alternatives:
-  Do not try to preserve sequential order but avoid performance penalty.
-
-
-9. Treat unlogged tables as normal (permanent) tables.
- Why?
-  Unlogged tables are not transient, so them have to survive node restart (unlike temporary tables).
-  But as far as compute node is stateless, we need to persist their data to storage node.
-  And it can only be done through the WAL.
-
- Alternatives?
-  * Store unlogged tables locally (violates requirement of stateless compute nodes).
-  * Prohibit unlogged tables at all.
-
-
-10. Support start Postgres in wal-redo mode
- Why?
-  To be able to apply WAL record and reconstruct pages at page server.
-
- Alternatives?
-  * Rewrite redo handlers in Rust
-  * Do not reconstruct pages at page server at all and do it at compute node.
-
-
-11. WAL proposer
- Why?
-  WAL proposer is communicating with safekeeper and ensures WAL durability by quorum writes.
-  It is currently implemented as patch to standard WAL sender.
-
- Alternatives?
-  Can be moved to extension if some extra callbacks will be added to wal sender code.
-
-
-12. Secure Computing BPF API wrapper.
- Why?
-  Pageserver delegates complex WAL decoding duties to Postgres,
-  which means that the latter might fall victim to carefully designed
-  malicious WAL records and start doing harmful things to the system.
-  To prevent this, it has been decided to limit possible interactions
-  with the outside world using the Secure Computing BPF mode.
-
- Alternatives:
-  * Rewrite redo handlers in Rust.
-  * Add more checks to guarantee correctness of WAL records.
-  * Move seccomp.c to extension
-  * Many other discussed approaches to neutralize incorrect WAL records vulnerabilities.
-
-
-13. Callbacks for replica feedbacks
- Why?
-  Allowing waproposer to interact with walsender code.
-
- Alternatives
-  Copy walsender code to walproposer.
-
-
-14. Support multiple SMGR implementations.
- Why?
-  Postgres provides abstract API for storage manager but it has only one implementation
-  and provides no way to replace it with custom storage manager.
-
- Alternatives?
-  None.
-
-
-15. Calculate database size as sum of all database relations.
- Why?
-  Postgres is calculating database size by traversing data directory
-  but as far as Zenith compute node is stateless we can not do it.
-
- Alternatives?
-  Send this request directly to pageserver and calculate real (physical) size
-  of Zenith representation of database/timeline, rather than sum logical size of all relations.
-
-
-----------------------------------------------
-Not currently committed but proposed:
-
-1. Disable ring buffer buffer manager strategies
- Why?
-  Postgres tries to avoid cache flushing by bulk operations (copy, seqscan, vacuum,...).
-  Even if there are free space in buffer cache, pages may be evicted.
-  Negative effect of it can be somehow compensated by file system cache, but in case of Zenith
-  cost of requesting page from page server is much higher.
-
- Alternatives?
-  Instead of just prohibiting ring buffer we may try to implement more flexible eviction policy,
-  for example copy evicted page from ring buffer to some other buffer if there is free space
-  in buffer cache.
-
-2. Disable marking page as dirty when hint bits are set.
- Why?
-  Postgres has to modify page twice: first time when some tuple is updated and second time when
-  hint bits are set. Wal logging hint bits updates requires FPI which significantly increase size of WAL.
-
- Alternatives?
-  Add special WAL record for setting page hints.
-
-3. Prefetching
- Why?
-  As far as pages in Zenith are loaded on demand, to reduce node startup time
-  and also sppedup some massive queries we need some mechanism for bulk loading to
-  reduce page request round-trip overhead.
-
-  Currently Postgres is supporting prefetching only for bitmap scan.
-  In Zenith we also use prefetch for sequential and index scan. For sequential scan we prefetch
-  some number of following pages. For index scan we prefetch pages of heap relation addressed by TIDs.
-
-4. Prewarming.
- Why?
-  Short downtime (or, in other words, fast compute node restart time) is one of the key feature of Zenith.
-  But overhead of request-response round-trip for loading pages on demand can make started node warm-up quite slow.
-  We can capture state of compute node buffer cache and send bulk request for this pages at startup.
--- a/docs/glossary.md
+++ b/docs/glossary.md
@@ -30,20 +30,12 @@ writes out the changes from in-memory layers into new layer files[]. This proces
 is called "checkpointing". The page server only creates layer files for
 relations that have been modified since the last checkpoint. 

-Configuration parameter `checkpoint_distance` defines the distance
-from current LSN to perform checkpoint of in-memory layers.
-Default is `DEFAULT_CHECKPOINT_DISTANCE`.
-Set this parameter to `0` to force checkpoint of every layer.
-
-Configuration parameter `checkpoint_period` defines the interval between checkpoint iterations.
-Default is `DEFAULT_CHECKPOINT_PERIOD`.
 ### Compute node

 Stateless Postgres node that stores data in pageserver.

 ### Garbage collection

-The process of removing old on-disk layers that are not needed by any timeline anymore.
 ### Fork

 Each of the separate segmented file sets in which a relation is stored. The main fork is where the actual data resides. There also exist two secondary forks for metadata: the free space map and the visibility map.
@@ -51,7 +43,7 @@ Each PostgreSQL fork is considered a separate relish.

 ### Layer

-Each layer corresponds to the specific version of a relish Segment in a range of LSNs.
+Each layer corresponds to one RELISH_SEG_SIZE slice of a relish in a range of LSNs.
 There are two kinds of layers, in-memory and on-disk layers. In-memory
 layers are used to ingest incoming WAL, and provide fast access
 to the recent page versions. On-disk layers are stored as files on disk, and
@@ -130,20 +122,6 @@ One repository corresponds to one Tenant.

 How much history do we need to keep around for PITR and read-only nodes?

-### Segment (PostgreSQL)
-
-NOTE: This is an overloaded term.
-
-A physical file that stores data for a given relation. File segments are
-limited in size by a compile-time setting (1 gigabyte by default), so if a
-relation exceeds that size, it is split into multiple segments.
-
-### Segment (Layered Repository)
-
-NOTE: This is an overloaded term.
-
-Segment is a RELISH_SEG_SIZE slice of relish (identified by a SegmentTag).
-
 ### SLRU

 SLRUs include pg_clog, pg_multixact/members, and
--- a/pageserver/Cargo.toml
+++ b/pageserver/Cargo.toml
@@ -4,6 +4,8 @@ version = "0.1.0"
 authors = ["Stas Kelvich <stas@zenith.tech>"]
 edition = "2018"

+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
 [dependencies]
 bookfile = "^0.3"
 chrono = "0.4.19"
@@ -14,10 +16,14 @@ byteorder = "1.4.3"
 futures = "0.3.13"
 hyper = "0.14"
 lazy_static = "1.4.0"
+slog-stdlog = "4.1.0"
+slog-scope = "4.4.0"
+slog-term = "2.8.0"
+slog = "2.7.0"
 log = "0.4.14"
 clap = "2.33.0"
 daemonize = "0.4.1"
-tokio = { version = "1.11", features = ["process", "macros", "fs"] }
+tokio = { version = "1.5.0", features = ["full"] }
 postgres-types = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 postgres-protocol = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 postgres = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
@@ -32,9 +38,6 @@ serde = { version = "1.0", features = ["derive"] }
 serde_json = "1"
 toml = "0.5"
 scopeguard = "1.1.0"
-rust-s3 = { version = "0.27.0-rc4", features = ["no-verify-ssl"] }
-async-trait = "0.1"
-const_format = "0.2.21"

 postgres_ffi = { path = "../postgres_ffi" }
 zenith_metrics = { path = "../zenith_metrics" }
--- a/pageserver/src/basebackup.rs
+++ b/pageserver/src/basebackup.rs
@@ -10,7 +10,6 @@
 //! This module is responsible for creation of such tarball
 //! from data stored in object storage.
 //!
-use anyhow::Result;
 use bytes::{BufMut, BytesMut};
 use log::*;
 use std::io;
@@ -23,7 +22,7 @@ use crate::relish::*;
 use crate::repository::Timeline;
 use postgres_ffi::xlog_utils::*;
 use postgres_ffi::*;
-use zenith_utils::lsn::Lsn;
+use zenith_utils::lsn::{Lsn, RecordLsn};

 /// This is short-living object only for the time of tarball creation,
 /// created mostly to avoid passing a lot of parameters between various functions
@@ -47,51 +46,30 @@ impl<'a> Basebackup<'a> {
        write: &'a mut dyn Write,
        timeline: &'a Arc<dyn Timeline>,
        req_lsn: Option<Lsn>,
-    ) -> Result<Basebackup<'a>> {
-        // Compute postgres doesn't have any previous WAL files, but the first
-        // record that it's going to write needs to include the LSN of the
-        // previous record (xl_prev). We include prev_record_lsn in the
-        // "zenith.signal" file, so that postgres can read it during startup.
-        //
-        // We don't keep full history of record boundaries in the page server,
-        // however, only the predecessor of the latest record on each
-        // timeline. So we can only provide prev_record_lsn when you take a
-        // base backup at the end of the timeline, i.e. at last_record_lsn.
-        // Even at the end of the timeline, we sometimes don't have a valid
-        // prev_lsn value; that happens if the timeline was just branched from
-        // an old LSN and it doesn't have any WAL of its own yet. We will set
-        // prev_lsn to Lsn(0) if we cannot provide the correct value.
-        let (backup_prev, backup_lsn) = if let Some(req_lsn) = req_lsn {
-            // Backup was requested at a particular LSN. Wait for it to arrive.
-            timeline.wait_lsn(req_lsn)?;
-
-            // If the requested point is the end of the timeline, we can
-            // provide prev_lsn. (get_last_record_rlsn() might return it as
-            // zero, though, if no WAL has been generated on this timeline
-            // yet.)
-            let end_of_timeline = timeline.get_last_record_rlsn();
-            if req_lsn == end_of_timeline.last {
-                (end_of_timeline.prev, req_lsn)
-            } else {
-                (Lsn(0), req_lsn)
+    ) -> Basebackup<'a> {
+        let RecordLsn {
+            last: lsn,
+            prev: prev_record_lsn,
+        } = if let Some(lsn) = req_lsn {
+            // FIXME: that wouldn't work since we don't know prev for old LSN's.
+            // Probably it is better to avoid using prev in compute node start
+            // at all and acept the fact that first WAL record in the timeline would
+            // have zero as prev. https://github.com/zenithdb/zenith/issues/506
+            RecordLsn {
+                last: lsn,
+                prev: lsn,
            }
        } else {
-            // Backup was requested at end of the timeline.
-            let end_of_timeline = timeline.get_last_record_rlsn();
-            (end_of_timeline.prev, end_of_timeline.last)
+            // Atomically get last and prev LSN's
+            timeline.get_last_record_rlsn()
        };

-        info!(
-            "taking basebackup lsn={}, prev_lsn={}",
-            backup_prev, backup_lsn
-        );
-
-        Ok(Basebackup {
+        Basebackup {
            ar: Builder::new(write),
            timeline,
-            lsn: backup_lsn,
-            prev_record_lsn: backup_prev,
-        })
+            lsn,
+            prev_record_lsn,
+        }
    }

    pub fn send_tarball(&mut self) -> anyhow::Result<()> {
@@ -106,10 +84,10 @@ impl<'a> Basebackup<'a> {
        for filepath in pg_constants::PGDATA_SPECIAL_FILES.iter() {
            if *filepath == "pg_hba.conf" {
                let data = pg_constants::PG_HBA.as_bytes();
-                let header = new_tar_header(filepath, data.len() as u64)?;
-                self.ar.append(&header, data)?;
+                let header = new_tar_header(&filepath, data.len() as u64)?;
+                self.ar.append(&header, &data[..])?;
            } else {
-                let header = new_tar_header(filepath, 0)?;
+                let header = new_tar_header(&filepath, 0)?;
                self.ar.append(&header, &mut io::empty())?;
            }
        }
@@ -159,9 +137,11 @@ impl<'a> Basebackup<'a> {
        let mut slru_buf: Vec<u8> =
            Vec::with_capacity(nblocks as usize * pg_constants::BLCKSZ as usize);
        for blknum in 0..nblocks {
-            let img =
-                self.timeline
-                    .get_page_at_lsn(RelishTag::Slru { slru, segno }, blknum, self.lsn)?;
+            let img = self.timeline.get_page_at_lsn_nowait(
+                RelishTag::Slru { slru, segno },
+                blknum,
+                self.lsn,
+            )?;
            assert!(img.len() == pg_constants::BLCKSZ as usize);

            slru_buf.extend_from_slice(&img);
@@ -180,18 +160,20 @@ impl<'a> Basebackup<'a> {
    // Along with them also send PG_VERSION for each database.
    //
    fn add_relmap_file(&mut self, spcnode: u32, dbnode: u32) -> anyhow::Result<()> {
-        let img = self.timeline.get_page_at_lsn(
+        let img = self.timeline.get_page_at_lsn_nowait(
            RelishTag::FileNodeMap { spcnode, dbnode },
            0,
            self.lsn,
        )?;
        let path = if spcnode == pg_constants::GLOBALTABLESPACE_OID {
+            let dst_path = "PG_VERSION";
            let version_bytes = pg_constants::PG_MAJORVERSION.as_bytes();
-            let header = new_tar_header("PG_VERSION", version_bytes.len() as u64)?;
-            self.ar.append(&header, version_bytes)?;
+            let header = new_tar_header(&dst_path, version_bytes.len() as u64)?;
+            self.ar.append(&header, &version_bytes[..])?;

-            let header = new_tar_header("global/PG_VERSION", version_bytes.len() as u64)?;
-            self.ar.append(&header, version_bytes)?;
+            let dst_path = format!("global/PG_VERSION");
+            let header = new_tar_header(&dst_path, version_bytes.len() as u64)?;
+            self.ar.append(&header, &version_bytes[..])?;

            String::from("global/pg_filenode.map") // filenode map for global tablespace
        } else {
@@ -206,7 +188,7 @@ impl<'a> Basebackup<'a> {
            let dst_path = format!("base/{}/PG_VERSION", dbnode);
            let version_bytes = pg_constants::PG_MAJORVERSION.as_bytes();
            let header = new_tar_header(&dst_path, version_bytes.len() as u64)?;
-            self.ar.append(&header, version_bytes)?;
+            self.ar.append(&header, &version_bytes[..])?;

            format!("base/{}/pg_filenode.map", dbnode)
        };
@@ -222,7 +204,7 @@ impl<'a> Basebackup<'a> {
    fn add_twophase_file(&mut self, xid: TransactionId) -> anyhow::Result<()> {
        let img = self
            .timeline
-            .get_page_at_lsn(RelishTag::TwoPhase { xid }, 0, self.lsn)?;
+            .get_page_at_lsn_nowait(RelishTag::TwoPhase { xid }, 0, self.lsn)?;

        let mut buf = BytesMut::new();
        buf.extend_from_slice(&img[..]);
@@ -240,12 +222,12 @@ impl<'a> Basebackup<'a> {
    // Also send zenith.signal file with extra bootstrap data.
    //
    fn add_pgcontrol_file(&mut self) -> anyhow::Result<()> {
-        let checkpoint_bytes = self
-            .timeline
-            .get_page_at_lsn(RelishTag::Checkpoint, 0, self.lsn)?;
+        let checkpoint_bytes =
+            self.timeline
+                .get_page_at_lsn_nowait(RelishTag::Checkpoint, 0, self.lsn)?;
        let pg_control_bytes =
            self.timeline
-                .get_page_at_lsn(RelishTag::ControlFile, 0, self.lsn)?;
+                .get_page_at_lsn_nowait(RelishTag::ControlFile, 0, self.lsn)?;
        let mut pg_control = ControlFileData::decode(&pg_control_bytes)?;
        let mut checkpoint = CheckPoint::decode(&checkpoint_bytes)?;

@@ -256,7 +238,7 @@ impl<'a> Basebackup<'a> {
            XLOG_SIZE_OF_XLOG_LONG_PHD as u32,
            pg_constants::WAL_SEGMENT_SIZE,
        );
-        checkpoint.redo = normalize_lsn(self.lsn, pg_constants::WAL_SEGMENT_SIZE).0;
+        checkpoint.redo = self.lsn.0 + self.lsn.calc_padding(8u32);

        //reset some fields we don't want to preserve
        //TODO Check this.
@@ -269,14 +251,9 @@ impl<'a> Basebackup<'a> {
        pg_control.state = pg_constants::DB_SHUTDOWNED;

        // add zenith.signal file
-        let xl_prev = if self.prev_record_lsn == Lsn(0) {
-            0xBAD0 // magic value to indicate that we don't know prev_lsn
-        } else {
-            self.prev_record_lsn.0
-        };
        self.ar.append(
            &new_tar_header("zenith.signal", 8)?,
-            &xl_prev.to_le_bytes()[..],
+            &self.prev_record_lsn.0.to_le_bytes()[..],
        )?;

        //send pg_control
--- a/pageserver/src/bin/pageserver.rs
+++ b/pageserver/src/bin/pageserver.rs
@@ -3,59 +3,43 @@
 //

 use log::*;
-use pageserver::defaults::*;
 use serde::{Deserialize, Serialize};
 use std::{
    env,
    net::TcpListener,
    path::{Path, PathBuf},
+    process::exit,
    str::FromStr,
    thread,
+    time::Duration,
 };
-use zenith_utils::{auth::JwtAuth, logging, postgres_backend::AuthType};
+use zenith_utils::{auth::JwtAuth, postgres_backend::AuthType};

-use anyhow::{bail, ensure, Context, Result};
+use anyhow::{ensure, Result};
 use clap::{App, Arg, ArgMatches};
 use daemonize::Daemonize;

-use pageserver::{
-    branches,
-    defaults::{DEFAULT_HTTP_LISTEN_ADDR, DEFAULT_PG_LISTEN_ADDR},
-    http, page_service, tenant_mgr, PageServerConf, RelishStorageConfig, S3Config, LOG_FILE_NAME,
-};
+use pageserver::{branches, http, logger, page_service, tenant_mgr, PageServerConf};
 use zenith_utils::http::endpoint;

-use const_format::formatcp;
+const DEFAULT_LISTEN_ADDR: &str = "127.0.0.1:64000";
+const DEFAULT_HTTP_ENDPOINT_ADDR: &str = "127.0.0.1:9898";
+
+const DEFAULT_GC_HORIZON: u64 = 64 * 1024 * 1024;
+const DEFAULT_GC_PERIOD: Duration = Duration::from_secs(10);
+
+const DEFAULT_SUPERUSER: &str = "zenith_admin";

 /// String arguments that can be declared via CLI or config file
 #[derive(Serialize, Deserialize)]
 struct CfgFileParams {
-    listen_pg_addr: Option<String>,
-    listen_http_addr: Option<String>,
-    checkpoint_distance: Option<String>,
-    checkpoint_period: Option<String>,
+    listen_addr: Option<String>,
+    http_endpoint_addr: Option<String>,
    gc_horizon: Option<String>,
    gc_period: Option<String>,
    pg_distrib_dir: Option<String>,
    auth_validation_public_key_path: Option<String>,
    auth_type: Option<String>,
-    // see https://github.com/alexcrichton/toml-rs/blob/6c162e6562c3e432bf04c82a3d1d789d80761a86/examples/enum_external.rs for enum deserialisation examples
-    relish_storage: Option<RelishStorage>,
-}
-
-#[derive(Serialize, Deserialize, Clone)]
-enum RelishStorage {
-    Local {
-        local_path: String,
-    },
-    AwsS3 {
-        bucket_name: String,
-        bucket_region: String,
-        #[serde(skip_serializing)]
-        access_key_id: Option<String>,
-        #[serde(skip_serializing)]
-        secret_access_key: Option<String>,
-    },
 }

 impl CfgFileParams {
@@ -65,32 +49,14 @@ impl CfgFileParams {
            arg_matches.value_of(arg_name).map(str::to_owned)
        };

-        let relish_storage = if let Some(local_path) = get_arg("relish-storage-local-path") {
-            Some(RelishStorage::Local { local_path })
-        } else if let Some((bucket_name, bucket_region)) =
-            get_arg("relish-storage-s3-bucket").zip(get_arg("relish-storage-region"))
-        {
-            Some(RelishStorage::AwsS3 {
-                bucket_name,
-                bucket_region,
-                access_key_id: get_arg("relish-storage-access-key"),
-                secret_access_key: get_arg("relish-storage-secret-access-key"),
-            })
-        } else {
-            None
-        };
-
        Self {
-            listen_pg_addr: get_arg("listen-pg"),
-            listen_http_addr: get_arg("listen-http"),
-            checkpoint_distance: get_arg("checkpoint_distance"),
-            checkpoint_period: get_arg("checkpoint_period"),
+            listen_addr: get_arg("listen"),
+            http_endpoint_addr: get_arg("http_endpoint"),
            gc_horizon: get_arg("gc_horizon"),
            gc_period: get_arg("gc_period"),
            pg_distrib_dir: get_arg("postgres-distrib"),
            auth_validation_public_key_path: get_arg("auth-validation-public-key-path"),
            auth_type: get_arg("auth-type"),
-            relish_storage,
        }
    }

@@ -98,10 +64,8 @@ impl CfgFileParams {
    fn or(self, other: CfgFileParams) -> Self {
        // TODO cleaner way to do this
        Self {
-            listen_pg_addr: self.listen_pg_addr.or(other.listen_pg_addr),
-            listen_http_addr: self.listen_http_addr.or(other.listen_http_addr),
-            checkpoint_distance: self.checkpoint_distance.or(other.checkpoint_distance),
-            checkpoint_period: self.checkpoint_period.or(other.checkpoint_period),
+            listen_addr: self.listen_addr.or(other.listen_addr),
+            http_endpoint_addr: self.http_endpoint_addr.or(other.http_endpoint_addr),
            gc_horizon: self.gc_horizon.or(other.gc_horizon),
            gc_period: self.gc_period.or(other.gc_period),
            pg_distrib_dir: self.pg_distrib_dir.or(other.pg_distrib_dir),
@@ -109,7 +73,6 @@ impl CfgFileParams {
                .auth_validation_public_key_path
                .or(other.auth_validation_public_key_path),
            auth_type: self.auth_type.or(other.auth_type),
-            relish_storage: self.relish_storage.or(other.relish_storage),
        }
    }

@@ -117,23 +80,14 @@ impl CfgFileParams {
    fn try_into_config(&self) -> Result<PageServerConf> {
        let workdir = PathBuf::from(".");

-        let listen_pg_addr = match self.listen_pg_addr.as_ref() {
+        let listen_addr = match self.listen_addr.as_ref() {
            Some(addr) => addr.clone(),
-            None => DEFAULT_PG_LISTEN_ADDR.to_owned(),
+            None => DEFAULT_LISTEN_ADDR.to_owned(),
        };

-        let listen_http_addr = match self.listen_http_addr.as_ref() {
+        let http_endpoint_addr = match self.http_endpoint_addr.as_ref() {
            Some(addr) => addr.clone(),
-            None => DEFAULT_HTTP_LISTEN_ADDR.to_owned(),
-        };
-
-        let checkpoint_distance: u64 = match self.checkpoint_distance.as_ref() {
-            Some(checkpoint_distance_str) => checkpoint_distance_str.parse()?,
-            None => DEFAULT_CHECKPOINT_DISTANCE,
-        };
-        let checkpoint_period = match self.checkpoint_period.as_ref() {
-            Some(checkpoint_period_str) => humantime::parse_duration(checkpoint_period_str)?,
-            None => DEFAULT_CHECKPOINT_PERIOD,
+            None => DEFAULT_HTTP_ENDPOINT_ADDR.to_owned(),
        };

        let gc_horizon: u64 = match self.gc_horizon.as_ref() {
@@ -159,11 +113,11 @@ impl CfgFileParams {
            .auth_type
            .as_ref()
            .map_or(Ok(AuthType::Trust), |auth_type| {
-                AuthType::from_str(auth_type)
+                AuthType::from_str(&auth_type)
            })?;

        if !pg_distrib_dir.join("bin/postgres").exists() {
-            bail!("Can't find postgres binary at {:?}", pg_distrib_dir);
+            anyhow::bail!("Can't find postgres binary at {:?}", pg_distrib_dir);
        }

        if auth_type == AuthType::ZenithJWT {
@@ -178,33 +132,11 @@ impl CfgFileParams {
            );
        }

-        let relish_storage_config =
-            self.relish_storage
-                .as_ref()
-                .map(|storage_params| match storage_params.clone() {
-                    RelishStorage::Local { local_path } => {
-                        RelishStorageConfig::LocalFs(PathBuf::from(local_path))
-                    }
-                    RelishStorage::AwsS3 {
-                        bucket_name,
-                        bucket_region,
-                        access_key_id,
-                        secret_access_key,
-                    } => RelishStorageConfig::AwsS3(S3Config {
-                        bucket_name,
-                        bucket_region,
-                        access_key_id,
-                        secret_access_key,
-                    }),
-                });
-
        Ok(PageServerConf {
            daemonize: false,

-            listen_pg_addr,
-            listen_http_addr,
-            checkpoint_distance,
-            checkpoint_period,
+            listen_addr,
+            http_endpoint_addr,
            gc_horizon,
            gc_period,

@@ -216,7 +148,6 @@ impl CfgFileParams {

            auth_validation_public_key_path,
            auth_type,
-            relish_storage_config,
        })
    }
 }
@@ -225,19 +156,11 @@ fn main() -> Result<()> {
    let arg_matches = App::new("Zenith page server")
        .about("Materializes WAL stream to pages and serves them to the postgres")
        .arg(
-            Arg::with_name("listen-pg")
+            Arg::with_name("listen")
                .short("l")
-                .long("listen-pg")
-                .alias("listen") // keep some compatibility
+                .long("listen")
                .takes_value(true)
-                .help(formatcp!("listen for incoming page requests on ip:port (default: {DEFAULT_PG_LISTEN_ADDR})")),
-        )
-        .arg(
-            Arg::with_name("listen-http")
-                .long("listen-http")
-                .alias("http_endpoint") // keep some compatibility
-                .takes_value(true)
-                .help(formatcp!("http endpoint address for metrics and management API calls on ip:port (default: {DEFAULT_HTTP_LISTEN_ADDR})")),
+                .help("listen for incoming page requests on ip:port (default: 127.0.0.1:5430)"),
        )
        .arg(
            Arg::with_name("daemonize")
@@ -252,18 +175,6 @@ fn main() -> Result<()> {
                .takes_value(false)
                .help("Initialize pageserver repo"),
        )
-        .arg(
-            Arg::with_name("checkpoint_distance")
-                .long("checkpoint_distance")
-                .takes_value(true)
-                .help("Distance from current LSN to perform checkpoint of in-memory layers"),
-        )
-        .arg(
-            Arg::with_name("checkpoint_period")
-                .long("checkpoint_period")
-                .takes_value(true)
-                .help("Interval between checkpoint iterations"),
-        )
        .arg(
            Arg::with_name("gc_horizon")
                .long("gc_horizon")
@@ -308,50 +219,10 @@ fn main() -> Result<()> {
                .takes_value(true)
                .help("Authentication scheme type. One of: Trust, MD5, ZenithJWT"),
        )
-        .arg(
-            Arg::with_name("relish-storage-local-path")
-                .long("relish-storage-local-path")
-                .takes_value(true)
-                .help("Path to the local directory, to be used as an external relish storage")
-                .conflicts_with_all(&[
-                    "relish-storage-s3-bucket",
-                    "relish-storage-region",
-                    "relish-storage-access-key",
-                    "relish-storage-secret-access-key",
-                ]),
-        )
-        .arg(
-            Arg::with_name("relish-storage-s3-bucket")
-                .long("relish-storage-s3-bucket")
-                .takes_value(true)
-                .help("Name of the AWS S3 bucket to use an external relish storage")
-                .requires("relish-storage-region"),
-        )
-        .arg(
-            Arg::with_name("relish-storage-region")
-                .long("relish-storage-region")
-                .takes_value(true)
-                .help("Region of the AWS S3 bucket"),
-        )
-        .arg(
-            Arg::with_name("relish-storage-access-key")
-                .long("relish-storage-access-key")
-                .takes_value(true)
-                .help("Credentials to access the AWS S3 bucket"),
-        )
-        .arg(
-            Arg::with_name("relish-storage-secret-access-key")
-                .long("relish-storage-secret-access-key")
-                .takes_value(true)
-                .help("Credentials to access the AWS S3 bucket"),
-        )
        .get_matches();

    let workdir = Path::new(arg_matches.value_of("workdir").unwrap_or(".zenith"));
-    let cfg_file_path = workdir
-        .canonicalize()
-        .with_context(|| format!("Error opening workdir '{}'", workdir.display()))?
-        .join("pageserver.toml");
+    let cfg_file_path = workdir.canonicalize()?.join("pageserver.toml");

    let args_params = CfgFileParams::from_args(&arg_matches);

@@ -363,37 +234,22 @@ fn main() -> Result<()> {
        args_params
    } else {
        // Supplement the CLI arguments with the config file
-        let cfg_file_contents = std::fs::read_to_string(&cfg_file_path)
-            .with_context(|| format!("No pageserver config at '{}'", cfg_file_path.display()))?;
-        let file_params: CfgFileParams = toml::from_str(&cfg_file_contents).with_context(|| {
-            format!(
-                "Failed to read '{}' as pageserver config",
-                cfg_file_path.display()
-            )
-        })?;
+        let cfg_file_contents = std::fs::read_to_string(&cfg_file_path)?;
+        let file_params: CfgFileParams = toml::from_str(&cfg_file_contents)?;
        args_params.or(file_params)
    };

    // Set CWD to workdir for non-daemon modes
-    env::set_current_dir(&workdir).with_context(|| {
-        format!(
-            "Failed to set application's current dir to '{}'",
-            workdir.display()
-        )
-    })?;
+    env::set_current_dir(&workdir)?;

    // Ensure the config is valid, even if just init-ing
-    let mut conf = params.try_into_config().with_context(|| {
-        format!(
-            "Pageserver config at '{}' is not valid",
-            cfg_file_path.display()
-        )
-    })?;
+    let mut conf = params.try_into_config()?;

    conf.daemonize = arg_matches.is_present("daemonize");

    if init && conf.daemonize {
-        bail!("--daemonize cannot be used with --init")
+        eprintln!("--daemonize cannot be used with --init");
+        exit(1);
    }

    // The configuration is all set up now. Turn it into a 'static
@@ -403,46 +259,32 @@ fn main() -> Result<()> {

    // Create repo and exit if init was requested
    if init {
-        branches::init_pageserver(conf, create_tenant).context("Failed to init pageserver")?;
+        branches::init_pageserver(conf, create_tenant)?;
        // write the config file
-        let cfg_file_contents = toml::to_string_pretty(&params)
-            .context("Failed to create pageserver config contents for initialisation")?;
+        let cfg_file_contents = toml::to_string_pretty(&params)?;
        // TODO support enable-auth flag
-        std::fs::write(&cfg_file_path, cfg_file_contents).with_context(|| {
-            format!(
-                "Failed to initialize pageserver config at '{}'",
-                cfg_file_path.display()
-            )
-        })?;
-        Ok(())
-    } else {
-        start_pageserver(conf).context("Failed to start pageserver")
+        std::fs::write(&cfg_file_path, cfg_file_contents)?;
+
+        return Ok(());
    }
+
+    start_pageserver(conf)
 }

 fn start_pageserver(conf: &'static PageServerConf) -> Result<()> {
    // Initialize logger
-    let (_scope_guard, log_file) = logging::init(LOG_FILE_NAME, conf.daemonize)?;
+    let (_scope_guard, log_file) = logger::init_logging(&conf, "pageserver.log")?;
+    let _log_guard = slog_stdlog::init()?;
+
+    // Note: this `info!(...)` macro comes from `log` crate
+    info!("standard logging redirected to slog");

    // TODO: Check that it looks like a valid repository before going further

-    // bind sockets before daemonizing so we report errors early and do not return until we are listening
-    info!(
-        "Starting pageserver http handler on {}",
-        conf.listen_http_addr
-    );
-    let http_listener = TcpListener::bind(conf.listen_http_addr.clone())?;
-
-    info!(
-        "Starting pageserver pg protocol handler on {}",
-        conf.listen_pg_addr
-    );
-    let pageserver_listener = TcpListener::bind(conf.listen_pg_addr.clone())?;
-
    if conf.daemonize {
        info!("daemonizing...");

-        // There shouldn't be any logging to stdin/stdout. Redirect it to the main log so
+        // There should'n be any logging to stdin/stdout. Redirect it to the main log so
        // that we will see any accidental manual fprintf's or backtraces.
        let stdout = log_file.try_clone().unwrap();
        let stderr = log_file;
@@ -459,12 +301,6 @@ fn start_pageserver(conf: &'static PageServerConf) -> Result<()> {
        }
    }

-    // Initialize tenant manager.
-    tenant_mgr::init(conf);
-
-    // keep join handles for spawned threads
-    let mut join_handles = vec![];
-
    // initialize authentication for incoming connections
    let auth = match &conf.auth_type {
        AuthType::Trust | AuthType::MD5 => None,
@@ -477,16 +313,21 @@ fn start_pageserver(conf: &'static PageServerConf) -> Result<()> {
    info!("Using auth: {:#?}", conf.auth_type);

    // Spawn a new thread for the http endpoint
-    // bind before launching separate thread so the error reported before startup exits
    let cloned = auth.clone();
-    let http_endpoint_thread = thread::Builder::new()
+    thread::Builder::new()
        .name("http_endpoint_thread".into())
        .spawn(move || {
            let router = http::make_router(conf, cloned);
-            endpoint::serve_thread_main(router, http_listener)
+            endpoint::serve_thread_main(router, conf.http_endpoint_addr.clone())
        })?;

-    join_handles.push(http_endpoint_thread);
+    // Check that we can bind to address before starting threads to simplify shutdown
+    // sequence if port is occupied.
+    info!("Starting pageserver on {}", conf.listen_addr);
+    let pageserver_listener = TcpListener::bind(conf.listen_addr.clone())?;
+
+    // Initialize tenant manager.
+    tenant_mgr::init(conf);

    // Spawn a thread to listen for connections. It will spawn further threads
    // for each connection.
@@ -496,13 +337,9 @@ fn start_pageserver(conf: &'static PageServerConf) -> Result<()> {
            page_service::thread_main(conf, auth, pageserver_listener, conf.auth_type)
        })?;

-    join_handles.push(page_service_thread);
+    page_service_thread
+        .join()
+        .expect("Page service thread has panicked")?;

-    for handle in join_handles.into_iter() {
-        handle
-            .join()
-            .expect("thread panicked")
-            .expect("thread exited with an error")
-    }
    Ok(())
 }
--- a/pageserver/src/branches.rs
+++ b/pageserver/src/branches.rs
@@ -17,77 +17,22 @@ use std::{
 use zenith_utils::zid::{ZTenantId, ZTimelineId};

 use log::*;
-use zenith_utils::logging;
 use zenith_utils::lsn::Lsn;

+use crate::logger;
+use crate::restore_local_repo;
 use crate::tenant_mgr;
 use crate::walredo::WalRedoManager;
 use crate::{repository::Repository, PageServerConf};
-use crate::{restore_local_repo, LOG_FILE_NAME};

 #[derive(Serialize, Deserialize, Clone)]
 pub struct BranchInfo {
    pub name: String,
    #[serde(with = "hex")]
    pub timeline_id: ZTimelineId,
-    pub latest_valid_lsn: Lsn,
+    pub latest_valid_lsn: Option<Lsn>,
    pub ancestor_id: Option<String>,
    pub ancestor_lsn: Option<String>,
-    pub current_logical_size: usize,
-    pub current_logical_size_non_incremental: usize,
-}
-
-impl BranchInfo {
-    pub fn from_path<T: AsRef<Path>>(
-        path: T,
-        conf: &PageServerConf,
-        tenantid: &ZTenantId,
-        repo: &Arc<dyn Repository>,
-    ) -> Result<Self> {
-        let name = path
-            .as_ref()
-            .file_name()
-            .unwrap()
-            .to_str()
-            .unwrap()
-            .to_string();
-        let timeline_id = std::fs::read_to_string(path)?.parse::<ZTimelineId>()?;
-
-        let timeline = repo.get_timeline(timeline_id)?;
-
-        let ancestor_path = conf.ancestor_path(&timeline_id, tenantid);
-        let mut ancestor_id: Option<String> = None;
-        let mut ancestor_lsn: Option<String> = None;
-
-        if ancestor_path.exists() {
-            let ancestor = std::fs::read_to_string(ancestor_path)?;
-            let mut strings = ancestor.split('@');
-
-            ancestor_id = Some(
-                strings
-                    .next()
-                    .with_context(|| "wrong branch ancestor point in time format")?
-                    .to_owned(),
-            );
-            ancestor_lsn = Some(
-                strings
-                    .next()
-                    .with_context(|| "wrong branch ancestor point in time format")?
-                    .to_owned(),
-            );
-        }
-
-        Ok(BranchInfo {
-            name,
-            timeline_id,
-            latest_valid_lsn: timeline.get_last_record_lsn(),
-            ancestor_id,
-            ancestor_lsn,
-            current_logical_size: timeline.get_current_logical_size(),
-            current_logical_size_non_incremental: timeline
-                .get_current_logical_size_non_incremental(timeline.get_last_record_lsn())?,
-        })
-    }
 }

 #[derive(Debug, Clone, Copy)]
@@ -98,8 +43,8 @@ pub struct PointInTime {

 pub fn init_pageserver(conf: &'static PageServerConf, create_tenant: Option<&str>) -> Result<()> {
    // Initialize logger
-    // use true as daemonize parameter because otherwise we pollute zenith cli output with a few pages long output of info messages
-    let (_scope_guard, _log_file) = logging::init(LOG_FILE_NAME, true)?;
+    let (_scope_guard, _log_file) = logger::init_logging(&conf, "pageserver.log")?;
+    let _log_guard = slog_stdlog::init()?;

    // We don't use the real WAL redo manager, because we don't want to spawn the WAL redo
    // process during repository initialization.
@@ -138,6 +83,9 @@ pub fn create_repo(
    fs::create_dir_all(&repo_dir)
        .with_context(|| format!("could not create directory {}", repo_dir.display()))?;

+    // Note: this `info!(...)` macro comes from `log` crate
+    info!("standard logging redirected to slog");
+
    fs::create_dir(conf.timelines_path(&tenantid))?;
    fs::create_dir_all(conf.branches_path(&tenantid))?;
    fs::create_dir_all(conf.tags_path(&tenantid))?;
@@ -170,7 +118,7 @@ fn get_lsn_from_controlfile(path: &Path) -> Result<Lsn> {
    Ok(Lsn(lsn))
 }

-// Create the cluster temporarily in 'initdbpath' directory inside the repository
+// Create the cluster temporarily in a initdbpath directory inside the repository
 // to get bootstrap data for timeline initialization.
 //
 fn run_initdb(conf: &'static PageServerConf, initdbpath: &Path) -> Result<()> {
@@ -218,11 +166,11 @@ fn bootstrap_timeline(

    info!("bootstrap_timeline {:?} at lsn {}", pgdata_path, lsn);

-    // Import the contents of the data directory at the initial checkpoint
-    // LSN, and any WAL after that.
-    let timeline = repo.create_empty_timeline(tli)?;
+    let timeline = repo.create_empty_timeline(tli, lsn)?;
    restore_local_repo::import_timeline_from_postgres_datadir(&pgdata_path, &*timeline, lsn)?;
-    timeline.checkpoint()?;
+
+    let wal_dir = pgdata_path.join("pg_wal");
+    restore_local_repo::import_timeline_wal(&wal_dir, &*timeline, timeline.get_last_record_lsn())?;

    println!(
        "created initial timeline {} timeline.lsn {}",
@@ -253,7 +201,7 @@ pub(crate) fn get_tenants(conf: &PageServerConf) -> Result<Vec<String>> {
 }

 pub(crate) fn get_branches(conf: &PageServerConf, tenantid: &ZTenantId) -> Result<Vec<BranchInfo>> {
-    let repo = tenant_mgr::get_repository_for_tenant(*tenantid)?;
+    let repo = tenant_mgr::get_repository_for_tenant(tenantid)?;

    // Each branch has a corresponding record (text file) in the refs/branches
    // with timeline_id.
@@ -262,7 +210,43 @@ pub(crate) fn get_branches(conf: &PageServerConf, tenantid: &ZTenantId) -> Resul
    std::fs::read_dir(&branches_dir)?
        .map(|dir_entry_res| {
            let dir_entry = dir_entry_res?;
-            BranchInfo::from_path(dir_entry.path(), conf, tenantid, &repo)
+            let name = dir_entry.file_name().to_str().unwrap().to_string();
+            let timeline_id = std::fs::read_to_string(dir_entry.path())?.parse::<ZTimelineId>()?;
+
+            let latest_valid_lsn = repo
+                .get_timeline(timeline_id)
+                .map(|timeline| timeline.get_last_record_lsn())
+                .ok();
+
+            let ancestor_path = conf.ancestor_path(&timeline_id, tenantid);
+            let mut ancestor_id: Option<String> = None;
+            let mut ancestor_lsn: Option<String> = None;
+
+            if ancestor_path.exists() {
+                let ancestor = std::fs::read_to_string(ancestor_path)?;
+                let mut strings = ancestor.split('@');
+
+                ancestor_id = Some(
+                    strings
+                        .next()
+                        .with_context(|| "wrong branch ancestor point in time format")?
+                        .to_owned(),
+                );
+                ancestor_lsn = Some(
+                    strings
+                        .next()
+                        .with_context(|| "wrong branch ancestor point in time format")?
+                        .to_owned(),
+                );
+            }
+
+            Ok(BranchInfo {
+                name,
+                timeline_id,
+                latest_valid_lsn,
+                ancestor_id,
+                ancestor_lsn,
+            })
        })
        .collect()
 }
@@ -273,36 +257,21 @@ pub(crate) fn create_branch(
    startpoint_str: &str,
    tenantid: &ZTenantId,
 ) -> Result<BranchInfo> {
-    let repo = tenant_mgr::get_repository_for_tenant(*tenantid)?;
+    let repo = tenant_mgr::get_repository_for_tenant(tenantid)?;

    if conf.branch_path(branchname, tenantid).exists() {
        anyhow::bail!("branch {} already exists", branchname);
    }

    let mut startpoint = parse_point_in_time(conf, startpoint_str, tenantid)?;
-    let timeline = repo.get_timeline(startpoint.timelineid)?;
+
    if startpoint.lsn == Lsn(0) {
        // Find end of WAL on the old timeline
-        let end_of_wal = timeline.get_last_record_lsn();
+        let end_of_wal = repo
+            .get_timeline(startpoint.timelineid)?
+            .get_last_record_lsn();
        info!("branching at end of WAL: {}", end_of_wal);
        startpoint.lsn = end_of_wal;
-    } else {
-        // Wait for the WAL to arrive and be processed on the parent branch up
-        // to the requested branch point. The repository code itself doesn't
-        // require it, but if we start to receive WAL on the new timeline,
-        // decoding the new WAL might need to look up previous pages, relation
-        // sizes etc. and that would get confused if the previous page versions
-        // are not in the repository yet.
-        timeline.wait_lsn(startpoint.lsn)?;
-    }
-    startpoint.lsn = startpoint.lsn.align();
-    if timeline.get_start_lsn() > startpoint.lsn {
-        anyhow::bail!(
-            "invalid startpoint {} for the branch {}: less than timeline start {}",
-            startpoint.lsn,
-            branchname,
-            timeline.get_start_lsn()
-        );
    }

    // create a new timeline directory for it
@@ -315,16 +284,14 @@ pub(crate) fn create_branch(
    // FIXME: there's a race condition, if you create a branch with the same
    // name concurrently.
    let data = newtli.to_string();
-    fs::write(conf.branch_path(branchname, tenantid), data)?;
+    fs::write(conf.branch_path(&branchname, tenantid), data)?;

    Ok(BranchInfo {
        name: branchname.to_string(),
        timeline_id: newtli,
-        latest_valid_lsn: startpoint.lsn,
+        latest_valid_lsn: Some(startpoint.lsn),
        ancestor_id: None,
        ancestor_lsn: None,
-        current_logical_size: 0,
-        current_logical_size_non_incremental: 0,
    })
 }

@@ -366,21 +333,21 @@ fn parse_point_in_time(

    // Check if it's a tag
    if lsn.is_none() {
-        let tagpath = conf.tag_path(name, tenantid);
+        let tagpath = conf.tag_path(name, &tenantid);
        if tagpath.exists() {
            let pointstr = fs::read_to_string(tagpath)?;

-            return parse_point_in_time(conf, &pointstr, tenantid);
+            return parse_point_in_time(conf, &pointstr, &tenantid);
        }
    }

    // Check if it's a branch
    // Check if it's branch @ LSN
-    let branchpath = conf.branch_path(name, tenantid);
+    let branchpath = conf.branch_path(name, &tenantid);
    if branchpath.exists() {
        let pointstr = fs::read_to_string(branchpath)?;

-        let mut result = parse_point_in_time(conf, &pointstr, tenantid)?;
+        let mut result = parse_point_in_time(conf, &pointstr, &tenantid)?;

        result.lsn = lsn.unwrap_or(Lsn(0));
        return Ok(result);
@@ -389,7 +356,7 @@ fn parse_point_in_time(
    // Check if it's a timelineid
    // Check if it's timelineid @ LSN
    if let Ok(timelineid) = ZTimelineId::from_str(name) {
-        let tlipath = conf.timeline_path(&timelineid, tenantid);
+        let tlipath = conf.timeline_path(&timelineid, &tenantid);
        if tlipath.exists() {
            return Ok(PointInTime {
                timelineid,
--- a/pageserver/src/http/openapi_spec.yml
+++ b/pageserver/src/http/openapi_spec.yml
@@ -54,52 +54,7 @@ paths:
            application/json:
              schema:
                $ref: "#/components/schemas/ForbiddenError"
-        "500":
-          description: Generic operation error
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/Error"
-  /v1/branch/{tenant_id}/{branch_name}:
-    parameters:
-      - name: tenant_id
-        in: path
-        required: true
-        schema:
-          type: string
-          format: hex
-      - name: branch_name
-        in: path
-        required: true
-        schema:
-          type: string
-    get:
-      description: Get branches for tenant
-      responses:
-        "200":
-          description: BranchInfo
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/BranchInfo"
-        "400":
-          description: Error when no tenant id found in path or no branch name
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/Error"
-        "401":
-          description: Unauthorized Error
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/UnauthorizedError"
-        "403":
-          description: Forbidden Error
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/ForbiddenError"
+
        "500":
          description: Generic operation error
          content:
@@ -248,9 +203,6 @@ components:
      required:
        - name
        - timeline_id
-        - latest_valid_lsn
-        - current_logical_size
-        - current_logical_size_non_incremental
      properties:
        name:
          type: string
@@ -261,10 +213,6 @@ components:
          type: string
        ancestor_lsn:
          type: string
-        current_logical_size:
-          type: integer
-        current_logical_size_non_incremental:
-          type: integer
    Error:
      type: object
      required:
--- a/pageserver/src/http/routes.rs
+++ b/pageserver/src/http/routes.rs
@@ -1,4 +1,3 @@
-use std::str::FromStr;
 use std::sync::Arc;

 use anyhow::Result;
@@ -19,8 +18,10 @@ use zenith_utils::http::{

 use super::models::BranchCreateRequest;
 use super::models::TenantCreateRequest;
-use crate::branches::BranchInfo;
-use crate::{branches, tenant_mgr, PageServerConf, ZTenantId};
+use crate::{
+    branches::{self},
+    tenant_mgr, PageServerConf, ZTenantId,
+};

 #[derive(Debug)]
 struct State {
@@ -56,33 +57,6 @@ fn get_config(request: &Request<Body>) -> &'static PageServerConf {
    get_state(request).conf
 }

-fn get_request_param<'a>(
-    request: &'a Request<Body>,
-    param_name: &str,
-) -> Result<&'a str, ApiError> {
-    match request.param(param_name) {
-        Some(arg) => Ok(arg),
-        None => {
-            return Err(ApiError::BadRequest(format!(
-                "no {} specified in path param",
-                param_name
-            )))
-        }
-    }
-}
-
-fn parse_request_param<T: FromStr>(
-    request: &Request<Body>,
-    param_name: &str,
-) -> Result<T, ApiError> {
-    match get_request_param(request, param_name)?.parse() {
-        Ok(v) => Ok(v),
-        Err(_) => Err(ApiError::BadRequest(
-            "failed to parse tenant id".to_string(),
-        )),
-    }
-}
-
 // healthcheck handler
 async fn status_handler(_: Request<Body>) -> Result<Response<Body>, ApiError> {
    Ok(Response::builder()
@@ -111,7 +85,16 @@ async fn branch_create_handler(mut request: Request<Body>) -> Result<Response<Bo
 }

 async fn branch_list_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
-    let tenantid: ZTenantId = parse_request_param(&request, "tenant_id")?;
+    let tenantid: ZTenantId = match request.param("tenant_id") {
+        Some(arg) => arg
+            .parse()
+            .map_err(|_| ApiError::BadRequest("failed to parse tenant id".to_string()))?,
+        None => {
+            return Err(ApiError::BadRequest(
+                "no tenant id specified in path param".to_string(),
+            ))
+        }
+    };

    check_permission(&request, Some(tenantid))?;

@@ -123,23 +106,6 @@ async fn branch_list_handler(request: Request<Body>) -> Result<Response<Body>, A
    Ok(json_response(StatusCode::OK, response_data)?)
 }

-// TODO add to swagger
-async fn branch_detail_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
-    let tenantid: ZTenantId = parse_request_param(&request, "tenant_id")?;
-    let branch_name: &str = get_request_param(&request, "branch_name")?;
-    let conf = get_state(&request).conf;
-    let path = conf.branch_path(branch_name, &tenantid);
-
-    let response_data = tokio::task::spawn_blocking(move || {
-        let repo = tenant_mgr::get_repository_for_tenant(tenantid)?;
-        BranchInfo::from_path(path, conf, &tenantid, &repo)
-    })
-    .await
-    .map_err(ApiError::from_err)??;
-
-    Ok(json_response(StatusCode::OK, response_data)?)
-}
-
 async fn tenant_list_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
    // check for management permission
    check_permission(&request, None)?;
@@ -193,7 +159,6 @@ pub fn make_router(
        .data(Arc::new(State::new(conf, auth)))
        .get("/v1/status", status_handler)
        .get("/v1/branch/:tenant_id", branch_list_handler)
-        .get("/v1/branch/:tenant_id/:branch_name", branch_detail_handler)
        .post("/v1/branch", branch_create_handler)
        .get("/v1/tenant", tenant_list_handler)
        .post("/v1/tenant", tenant_create_handler)
--- a/pageserver/src/layered_repository.rs
+++ b/pageserver/src/layered_repository.rs
--- a/pageserver/src/layered_repository/README.md
+++ b/pageserver/src/layered_repository/README.md
@@ -4,60 +4,7 @@ The on-disk format is based on immutable files. The page server
 receives a stream of incoming WAL, parses the WAL records to determine
 which pages they apply to, and accumulates the incoming changes in
 memory. Every now and then, the accumulated changes are written out to
-new immutable files. This process is called checkpointing. Old versions
-of on-disk files that are not needed by any timeline are removed by GC
-process.
-
-# Terms used in layered repository
-
- Relish - one PostgreSQL relation or similarly treated file.
- Segment - one slice of a Relish that is stored in a LayeredTimeline.
- Layer -  specific version of a relish Segment in a range of LSNs.
-
-Layers can be InMemory or OnDisk:
- InMemory layer is not durably stored and needs to rebuild from WAL on pageserver start.
- OnDisk layer is durably stored.
-
-OnDisk layers can be Image or Delta:
- ImageLayer represents an image or a snapshot of a segment at one particular LSN.
- DeltaLayer represents a collection of WAL records or page images in a range of LSNs.
-
-Dropped segments are always represented on disk by DeltaLayer.
-
-LSN range defined by start_lsn and end_lsn:
- start_lsn is inclusive.
- end_lsn is exclusive.
-
-For an open in-memory layer, the end_lsn is MAX_LSN. For a frozen
-in-memory layer or a delta layer, it is a valid end bound. An image
-layer represents snapshot at one LSN, so end_lsn is always the
-snapshot LSN + 1
-
-Layers can be open or historical:
- Open layer is a writeable one. Only InMemory layer can be open.
-FIXME: If open layer is dropped, it is not writeable, so it should be turned into historical, 
-but now it is not implemented - see bug #569.
- Historical layer is the one that cannot be modified anymore. Now only OnDisk layers can be historical.
-
- LayerMap - a map that tracks what layers exist for all the relishes in a timeline.
-
-LayerMap consists of two data structures:
- segs - All the layers keyed by segment tag
- open_layers - data structure that hold all open layers ordered by oldest_pending_lsn for quick access during checkpointing. oldest_pending_lsn is the LSN of the oldest page version stored in this layer.
-
-All operations that update InMemory Layers should update both structures to keep them up-to-date.
-
- LayeredTimeline - implements Timeline interface.
-
-All methods of LayeredTimeline are aware of its ancestors and return data taking them into account.
-TODO: Are there any exceptions to this?
-For example, timeline.list_rels(lsn) will return all segments that are visible in this timeline at the LSN,
-including ones that were not modified in this timeline and thus don't have a layer in the timeline's LayerMap.
-
-TODO:
-Describe GC and checkpoint interval settings.
-
-# Layer files (On-disk layers)
+new files.

 The files are called "layer files". Each layer file corresponds
 to one RELISH_SEG_SIZE slice of a PostgreSQL relation fork or
--- a/pageserver/src/layered_repository/blob.rs
+++ b/pageserver/src/layered_repository/blob.rs
@@ -16,14 +16,14 @@ pub fn read_blob(reader: &BoundedReader<&'_ File>, range: &BlobRange) -> Result<
    Ok(buf)
 }

-pub struct BlobWriter<W> {
-    writer: ChapterWriter<W>,
+pub struct BlobWriter {
+    writer: ChapterWriter<File>,
    offset: u64,
 }

-impl<W: Write> BlobWriter<W> {
+impl BlobWriter {
    // This function takes a BookWriter and creates a new chapter to ensure offset is 0.
-    pub fn new(book_writer: BookWriter<W>, chapter_id: impl Into<ChapterId>) -> Self {
+    pub fn new(book_writer: BookWriter<File>, chapter_id: impl Into<ChapterId>) -> Self {
        let writer = book_writer.new_chapter(chapter_id);
        Self { writer, offset: 0 }
    }
@@ -39,7 +39,7 @@ impl<W: Write> BlobWriter<W> {
        Ok(range)
    }

-    pub fn close(self) -> bookfile::Result<BookWriter<W>> {
+    pub fn close(self) -> bookfile::Result<BookWriter<File>> {
        self.writer.close()
    }
 }
--- a/pageserver/src/layered_repository/delta_layer.rs
+++ b/pageserver/src/layered_repository/delta_layer.rs
@@ -56,7 +56,7 @@ use std::collections::BTreeMap;
 use std::fmt::Write as _;
 use std::fs;
 use std::fs::File;
-use std::io::{BufWriter, Write};
+use std::io::Write;
 use std::ops::Bound::Included;
 use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex, MutexGuard};
@@ -69,7 +69,7 @@ use zenith_utils::lsn::Lsn;
 use super::blob::{read_blob, BlobRange};

 // Magic constant to identify a Zenith delta file
-pub const DELTA_FILE_MAGIC: u32 = 0x5A616E01;
+static DELTA_FILE_MAGIC: u32 = 0x5A616E01;

 /// Mapping from (block #, lsn) -> page/WAL record
 /// byte ranges in PAGE_VERSIONS_CHAPTER
@@ -79,36 +79,6 @@ static PAGE_VERSION_METAS_CHAPTER: u64 = 1;
 static PAGE_VERSIONS_CHAPTER: u64 = 2;
 static REL_SIZES_CHAPTER: u64 = 3;

-/// Contains the [`Summary`] struct
-static SUMMARY_CHAPTER: u64 = 4;
-
-#[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
-struct Summary {
-    tenantid: ZTenantId,
-    timelineid: ZTimelineId,
-    seg: SegmentTag,
-
-    start_lsn: Lsn,
-    end_lsn: Lsn,
-
-    dropped: bool,
-}
-
-impl From<&DeltaLayer> for Summary {
-    fn from(layer: &DeltaLayer) -> Self {
-        Self {
-            tenantid: layer.tenantid,
-            timelineid: layer.timelineid,
-            seg: layer.seg,
-
-            start_lsn: layer.start_lsn,
-            end_lsn: layer.end_lsn,
-
-            dropped: layer.dropped,
-        }
-    }
-}
-
 #[derive(Serialize, Deserialize)]
 struct PageVersionMeta {
    page_image_range: Option<BlobRange>,
@@ -160,23 +130,23 @@ pub struct DeltaLayerInner {

 impl Layer for DeltaLayer {
    fn get_timeline_id(&self) -> ZTimelineId {
-        self.timelineid
+        return self.timelineid;
    }

    fn get_seg_tag(&self) -> SegmentTag {
-        self.seg
+        return self.seg;
    }

    fn is_dropped(&self) -> bool {
-        self.dropped
+        return self.dropped;
    }

    fn get_start_lsn(&self) -> Lsn {
-        self.start_lsn
+        return self.start_lsn;
    }

    fn get_end_lsn(&self) -> Lsn {
-        self.end_lsn
+        return self.end_lsn;
    }

    fn filename(&self) -> PathBuf {
@@ -191,20 +161,6 @@ impl Layer for DeltaLayer {
        )
    }

-    fn path(&self) -> Option<PathBuf> {
-        Some(Self::path_for(
-            &self.path_or_conf,
-            self.timelineid,
-            self.tenantid,
-            &DeltaFileName {
-                seg: self.seg,
-                start_lsn: self.start_lsn,
-                end_lsn: self.end_lsn,
-                dropped: self.dropped,
-            },
-        ))
-    }
-
    /// Look up given page in the cache.
    fn get_page_reconstruct_data(
        &self,
@@ -212,7 +168,7 @@ impl Layer for DeltaLayer {
        lsn: Lsn,
        reconstruct_data: &mut PageReconstructData,
    ) -> Result<PageReconstructResult> {
-        let mut need_image = true;
+        let mut cont_lsn: Option<Lsn> = Some(lsn);

        assert!(self.seg.blknum_in_seg(blknum));

@@ -229,12 +185,12 @@ impl Layer for DeltaLayer {
            let mut iter = inner
                .page_version_metas
                .range((Included(&minkey), Included(&maxkey)));
-            while let Some(((_blknum, _entry_lsn), entry)) = iter.next_back() {
+            while let Some(((_blknum, entry_lsn), entry)) = iter.next_back() {
                if let Some(img_range) = &entry.page_image_range {
                    // Found a page image, return it
                    let img = Bytes::from(read_blob(&page_version_reader, img_range)?);
                    reconstruct_data.page_img = Some(img);
-                    need_image = false;
+                    cont_lsn = None;
                    break;
                } else if let Some(rec_range) = &entry.record_range {
                    let rec = WALRecord::des(&read_blob(&page_version_reader, rec_range)?)?;
@@ -242,8 +198,11 @@ impl Layer for DeltaLayer {
                    reconstruct_data.records.push(rec);
                    if will_init {
                        // This WAL record initializes the page, so no need to go further back
-                        need_image = false;
+                        cont_lsn = None;
                        break;
+                    } else {
+                        // This WAL record needs to be applied against an older page image
+                        cont_lsn = Some(*entry_lsn);
                    }
                } else {
                    // No base image, and no WAL record. Huh?
@@ -256,14 +215,14 @@ impl Layer for DeltaLayer {

        // If an older page image is needed to reconstruct the page, let the
        // caller know about the predecessor layer.
-        if need_image {
+        if let Some(cont_lsn) = cont_lsn {
            if let Some(cont_layer) = &self.predecessor {
                Ok(PageReconstructResult::Continue(
-                    self.start_lsn,
+                    cont_lsn,
                    Arc::clone(cont_layer),
                ))
            } else {
-                Ok(PageReconstructResult::Missing(self.start_lsn))
+                Ok(PageReconstructResult::Missing(cont_lsn))
            }
        } else {
            Ok(PageReconstructResult::Complete)
@@ -292,6 +251,8 @@ impl Layer for DeltaLayer {

    /// Does this segment exist at given LSN?
    fn get_seg_exists(&self, lsn: Lsn) -> Result<bool> {
+        assert!(lsn >= self.start_lsn);
+
        // Is the requested LSN after the rel was dropped?
        if self.dropped && lsn >= self.end_lsn {
            return Ok(false);
@@ -315,9 +276,7 @@ impl Layer for DeltaLayer {

    fn delete(&self) -> Result<()> {
        // delete underlying file
-        if let Some(path) = self.path() {
-            fs::remove_file(path)?;
-        }
+        fs::remove_file(self.path())?;
        Ok(())
    }

@@ -328,8 +287,8 @@ impl Layer for DeltaLayer {
    /// debugging function to print out the contents of the layer
    fn dump(&self) -> Result<()> {
        println!(
-            "----- delta layer for ten {} tli {} seg {} {}-{} ----",
-            self.tenantid, self.timelineid, self.seg, self.start_lsn, self.end_lsn
+            "----- delta layer for {} {}-{} ----",
+            self.seg, self.start_lsn, self.end_lsn
        );

        println!("--- relsizes ---");
@@ -344,7 +303,7 @@ impl Layer for DeltaLayer {
            let mut desc = String::new();

            if let Some(page_image_range) = v.page_image_range.as_ref() {
-                let image = read_blob(&chapter, page_image_range)?;
+                let image = read_blob(&chapter, &page_image_range)?;
                write!(&mut desc, " img {} bytes", image.len())?;
            }
            if let Some(record_range) = v.record_range.as_ref() {
@@ -367,6 +326,20 @@ impl Layer for DeltaLayer {
 }

 impl DeltaLayer {
+    fn path(&self) -> PathBuf {
+        Self::path_for(
+            &self.path_or_conf,
+            self.timelineid,
+            self.tenantid,
+            &DeltaFileName {
+                seg: self.seg,
+                start_lsn: self.start_lsn,
+                end_lsn: self.end_lsn,
+                dropped: self.dropped,
+            },
+        )
+    }
+
    fn path_for(
        path_or_conf: &PathOrConf,
        timelineid: ZTimelineId,
@@ -381,15 +354,13 @@ impl DeltaLayer {
        }
    }

-    /// Create a new delta file, using the given page versions and relsizes.
-    /// The page versions are passed by an iterator; the iterator must return
-    /// page versions in blknum+lsn order.
+    /// Create a new delta file, using the given btreemaps containing the page versions and
+    /// relsizes.
    ///
    /// This is used to write the in-memory layer to disk. The in-memory layer uses the same
    /// data structure with two btreemaps as we do, so passing the btreemaps is currently
    /// expedient.
-    #[allow(clippy::too_many_arguments)]
-    pub fn create<'a>(
+    pub fn create(
        conf: &'static PageServerConf,
        timelineid: ZTimelineId,
        tenantid: ZTenantId,
@@ -398,57 +369,52 @@ impl DeltaLayer {
        end_lsn: Lsn,
        dropped: bool,
        predecessor: Option<Arc<dyn Layer>>,
-        page_versions: impl Iterator<Item = (&'a (u32, Lsn), &'a PageVersion)>,
+        page_versions: BTreeMap<(u32, Lsn), PageVersion>,
        relsizes: BTreeMap<Lsn, u32>,
    ) -> Result<DeltaLayer> {
        let delta_layer = DeltaLayer {
            path_or_conf: PathOrConf::Conf(conf),
-            timelineid,
-            tenantid,
-            seg,
-            start_lsn,
+            timelineid: timelineid,
+            tenantid: tenantid,
+            seg: seg,
+            start_lsn: start_lsn,
            end_lsn,
            dropped,
            inner: Mutex::new(DeltaLayerInner {
                loaded: true,
                page_version_metas: BTreeMap::new(),
-                relsizes,
+                relsizes: relsizes,
            }),
            predecessor,
        };
        let mut inner = delta_layer.inner.lock().unwrap();

        // Write the in-memory btreemaps into a file
-        let path = delta_layer
-            .path()
-            .expect("DeltaLayer is supposed to have a layer path on disk");
+        let path = delta_layer.path();

        // Note: This overwrites any existing file. There shouldn't be any.
        // FIXME: throw an error instead?
        let file = File::create(&path)?;
-        let buf_writer = BufWriter::new(file);
-        let book = BookWriter::new(buf_writer, DELTA_FILE_MAGIC)?;
+        let book = BookWriter::new(file, DELTA_FILE_MAGIC)?;

        let mut page_version_writer = BlobWriter::new(book, PAGE_VERSIONS_CHAPTER);

        for (key, page_version) in page_versions {
            let page_image_range = page_version
                .page_image
-                .as_ref()
-                .map(|page_image| page_version_writer.write_blob(page_image))
+                .map(|page_image| page_version_writer.write_blob(page_image.as_ref()))
                .transpose()?;

            let record_range = page_version
                .record
-                .as_ref()
                .map(|record| {
-                    let buf = WALRecord::ser(record)?;
+                    let buf = WALRecord::ser(&record)?;
                    page_version_writer.write_blob(&buf)
                })
                .transpose()?;

            let old = inner.page_version_metas.insert(
-                *key,
+                key,
                PageVersionMeta {
                    page_image_range,
                    record_range,
@@ -472,21 +438,6 @@ impl DeltaLayer {
        chapter.write_all(&buf)?;
        let book = chapter.close()?;

-        let mut chapter = book.new_chapter(SUMMARY_CHAPTER);
-        let summary = Summary {
-            tenantid,
-            timelineid,
-            seg,
-
-            start_lsn,
-            end_lsn,
-
-            dropped,
-        };
-        Summary::ser_into(&summary, &mut chapter)?;
-        let book = chapter.close()?;
-
-        // This flushes the underlying 'buf_writer'.
        book.close()?;

        trace!("saved {}", &path.display());
@@ -528,31 +479,6 @@ impl DeltaLayer {

        let (path, book) = self.open_book()?;

-        match &self.path_or_conf {
-            PathOrConf::Conf(_) => {
-                let chapter = book.read_chapter(SUMMARY_CHAPTER)?;
-                let actual_summary = Summary::des(&chapter)?;
-
-                let expected_summary = Summary::from(self);
-
-                if actual_summary != expected_summary {
-                    bail!("in-file summary does not match expected summary. actual = {:?} expected = {:?}", actual_summary, expected_summary);
-                }
-            }
-            PathOrConf::Path(path) => {
-                let actual_filename = Path::new(path.file_name().unwrap());
-                let expected_filename = self.filename();
-
-                if actual_filename != expected_filename {
-                    println!(
-                        "warning: filename does not match what is expected from in-file summary"
-                    );
-                    println!("actual: {:?}", actual_filename);
-                    println!("expected: {:?}", expected_filename);
-                }
-            }
-        }
-
        let chapter = book.read_chapter(PAGE_VERSION_METAS_CHAPTER)?;
        let page_version_metas = BTreeMap::des(&chapter)?;

@@ -598,24 +524,26 @@ impl DeltaLayer {
    /// Create a DeltaLayer struct representing an existing file on disk.
    ///
    /// This variant is only used for debugging purposes, by the 'dump_layerfile' binary.
-    pub fn new_for_path(path: &Path, book: &Book<File>) -> Result<Self> {
-        let chapter = book.read_chapter(SUMMARY_CHAPTER)?;
-        let summary = Summary::des(&chapter)?;
-
-        Ok(DeltaLayer {
+    pub fn new_for_path(
+        path: &Path,
+        timelineid: ZTimelineId,
+        tenantid: ZTenantId,
+        filename: &DeltaFileName,
+    ) -> DeltaLayer {
+        DeltaLayer {
            path_or_conf: PathOrConf::Path(path.to_path_buf()),
-            timelineid: summary.timelineid,
-            tenantid: summary.tenantid,
-            seg: summary.seg,
-            start_lsn: summary.start_lsn,
-            end_lsn: summary.end_lsn,
-            dropped: summary.dropped,
+            timelineid,
+            tenantid,
+            seg: filename.seg,
+            start_lsn: filename.start_lsn,
+            end_lsn: filename.end_lsn,
+            dropped: filename.dropped,
            inner: Mutex::new(DeltaLayerInner {
                loaded: false,
                page_version_metas: BTreeMap::new(),
                relsizes: BTreeMap::new(),
            }),
            predecessor: None,
-        })
+        }
    }
 }
--- a/pageserver/src/layered_repository/filename.rs
+++ b/pageserver/src/layered_repository/filename.rs
@@ -111,10 +111,8 @@ impl DeltaFileName {
            dropped,
        })
    }
-}

-impl fmt::Display for DeltaFileName {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn to_string(&self) -> String {
        let basename = match self.seg.rel {
            RelishTag::Relation(reltag) => format!(
                "rel_{}_{}_{}_{}",
@@ -136,12 +134,11 @@ impl fmt::Display for DeltaFileName {
                format!("pg_filenodemap_{}_{}", spcnode, dbnode)
            }
            RelishTag::TwoPhase { xid } => format!("pg_twophase_{}", xid),
-            RelishTag::Checkpoint => "pg_control_checkpoint".to_string(),
-            RelishTag::ControlFile => "pg_control".to_string(),
+            RelishTag::Checkpoint => format!("pg_control_checkpoint"),
+            RelishTag::ControlFile => format!("pg_control"),
        };

-        write!(
-            f,
+        format!(
            "{}_{}_{:016X}_{:016X}{}",
            basename,
            self.seg.segno,
@@ -152,6 +149,12 @@ impl fmt::Display for DeltaFileName {
    }
 }

+impl fmt::Display for DeltaFileName {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.to_string())
+    }
+}
+
 #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone)]
 pub struct ImageFileName {
    pub seg: SegmentTag,
@@ -230,10 +233,8 @@ impl ImageFileName {

        Some(ImageFileName { seg, lsn })
    }
-}

-impl fmt::Display for ImageFileName {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn to_string(&self) -> String {
        let basename = match self.seg.rel {
            RelishTag::Relation(reltag) => format!(
                "rel_{}_{}_{}_{}",
@@ -255,12 +256,11 @@ impl fmt::Display for ImageFileName {
                format!("pg_filenodemap_{}_{}", spcnode, dbnode)
            }
            RelishTag::TwoPhase { xid } => format!("pg_twophase_{}", xid),
-            RelishTag::Checkpoint => "pg_control_checkpoint".to_string(),
-            RelishTag::ControlFile => "pg_control".to_string(),
+            RelishTag::Checkpoint => format!("pg_control_checkpoint"),
+            RelishTag::ControlFile => format!("pg_control"),
        };

-        write!(
-            f,
+        format!(
            "{}_{}_{:016X}",
            basename,
            self.seg.segno,
@@ -269,6 +269,12 @@ impl fmt::Display for ImageFileName {
    }
 }

+impl fmt::Display for ImageFileName {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "{}", self.to_string())
+    }
+}
+
 /// Scan timeline directory and create ImageFileName and DeltaFilename
 /// structs representing all files on disk
 ///
@@ -296,7 +302,7 @@ pub fn list_files(
            warn!("unrecognized filename in timeline dir: {}", fname);
        }
    }
-    Ok((imgfiles, deltafiles))
+    return Ok((imgfiles, deltafiles));
 }

 /// Helper enum to hold a PageServerConf, or a path
--- a/pageserver/src/layered_repository/image_layer.rs
+++ b/pageserver/src/layered_repository/image_layer.rs
@@ -29,53 +29,27 @@ use crate::layered_repository::LayeredTimeline;
 use crate::layered_repository::RELISH_SEG_SIZE;
 use crate::PageServerConf;
 use crate::{ZTenantId, ZTimelineId};
-use anyhow::{anyhow, bail, ensure, Result};
+use anyhow::{anyhow, ensure, Result};
 use bytes::Bytes;
 use log::*;
-use serde::{Deserialize, Serialize};
 use std::convert::TryInto;
 use std::fs;
 use std::fs::File;
-use std::io::{BufWriter, Write};
+use std::io::Write;
 use std::path::{Path, PathBuf};
 use std::sync::{Mutex, MutexGuard};

 use bookfile::{Book, BookWriter};

-use zenith_utils::bin_ser::BeSer;
 use zenith_utils::lsn::Lsn;

 // Magic constant to identify a Zenith segment image file
-pub const IMAGE_FILE_MAGIC: u32 = 0x5A616E01 + 1;
+const IMAGE_FILE_MAGIC: u32 = 0x5A616E01 + 1;

 /// Contains each block in block # order
 const BLOCKY_IMAGES_CHAPTER: u64 = 1;
 const NONBLOCKY_IMAGE_CHAPTER: u64 = 2;

-/// Contains the [`Summary`] struct
-const SUMMARY_CHAPTER: u64 = 3;
-
-#[derive(Debug, Serialize, Deserialize, PartialEq, Eq)]
-struct Summary {
-    tenantid: ZTenantId,
-    timelineid: ZTimelineId,
-    seg: SegmentTag,
-
-    lsn: Lsn,
-}
-
-impl From<&ImageLayer> for Summary {
-    fn from(layer: &ImageLayer) -> Self {
-        Self {
-            tenantid: layer.tenantid,
-            timelineid: layer.timelineid,
-            seg: layer.seg,
-
-            lsn: layer.lsn,
-        }
-    }
-}
-
 const BLOCK_SIZE: usize = 8192;

 ///
@@ -123,37 +97,24 @@ impl Layer for ImageLayer {
        )
    }

-    fn path(&self) -> Option<PathBuf> {
-        Some(Self::path_for(
-            &self.path_or_conf,
-            self.timelineid,
-            self.tenantid,
-            &ImageFileName {
-                seg: self.seg,
-                lsn: self.lsn,
-            },
-        ))
-    }
-
    fn get_timeline_id(&self) -> ZTimelineId {
-        self.timelineid
+        return self.timelineid;
    }

    fn get_seg_tag(&self) -> SegmentTag {
-        self.seg
+        return self.seg;
    }

    fn is_dropped(&self) -> bool {
-        false
+        return false;
    }

    fn get_start_lsn(&self) -> Lsn {
-        self.lsn
+        return self.lsn;
    }

    fn get_end_lsn(&self) -> Lsn {
-        // End-bound is exclusive
-        self.lsn + 1
+        return self.lsn;
    }

    /// Look up given page in the file
@@ -196,7 +157,9 @@ impl Layer for ImageLayer {
    }

    /// Get size of the segment
-    fn get_seg_size(&self, _lsn: Lsn) -> Result<u32> {
+    fn get_seg_size(&self, lsn: Lsn) -> Result<u32> {
+        assert!(lsn >= self.lsn);
+
        let inner = self.load()?;
        match inner.image_type {
            ImageType::Blocky { num_blocks } => Ok(num_blocks),
@@ -205,7 +168,8 @@ impl Layer for ImageLayer {
    }

    /// Does this segment exist at given LSN?
-    fn get_seg_exists(&self, _lsn: Lsn) -> Result<bool> {
+    fn get_seg_exists(&self, lsn: Lsn) -> Result<bool> {
+        assert!(lsn >= self.lsn);
        Ok(true)
    }

@@ -222,9 +186,7 @@ impl Layer for ImageLayer {

    fn delete(&self) -> Result<()> {
        // delete underlying file
-        if let Some(path) = self.path() {
-            fs::remove_file(path)?;
-        }
+        fs::remove_file(self.path())?;
        Ok(())
    }

@@ -234,10 +196,7 @@ impl Layer for ImageLayer {

    /// debugging function to print out the contents of the layer
    fn dump(&self) -> Result<()> {
-        println!(
-            "----- image layer for ten {} tli {} seg {} at {} ----",
-            self.tenantid, self.timelineid, self.seg, self.lsn
-        );
+        println!("----- image layer for {} at {} ----", self.seg, self.lsn);

        let inner = self.load()?;

@@ -255,6 +214,18 @@ impl Layer for ImageLayer {
 }

 impl ImageLayer {
+    fn path(&self) -> PathBuf {
+        Self::path_for(
+            &self.path_or_conf,
+            self.timelineid,
+            self.tenantid,
+            &ImageFileName {
+                seg: self.seg,
+                lsn: self.lsn,
+            },
+        )
+    }
+
    fn path_for(
        path_or_conf: &PathOrConf,
        timelineid: ZTimelineId,
@@ -288,10 +259,10 @@ impl ImageLayer {

        let layer = ImageLayer {
            path_or_conf: PathOrConf::Conf(conf),
-            timelineid,
-            tenantid,
-            seg,
-            lsn,
+            timelineid: timelineid,
+            tenantid: tenantid,
+            seg: seg,
+            lsn: lsn,
            inner: Mutex::new(ImageLayerInner {
                loaded: true,
                image_type: image_type.clone(),
@@ -300,14 +271,12 @@ impl ImageLayer {
        let inner = layer.inner.lock().unwrap();

        // Write the images into a file
-        let path = layer
-            .path()
-            .expect("ImageLayer is supposed to have a layer path on disk");
+        let path = layer.path();
+
        // Note: This overwrites any existing file. There shouldn't be any.
        // FIXME: throw an error instead?
        let file = File::create(&path)?;
-        let buf_writer = BufWriter::new(file);
-        let book = BookWriter::new(buf_writer, IMAGE_FILE_MAGIC)?;
+        let book = BookWriter::new(file, IMAGE_FILE_MAGIC)?;

        let book = match &image_type {
            ImageType::Blocky { .. } => {
@@ -325,18 +294,6 @@ impl ImageLayer {
            }
        };

-        let mut chapter = book.new_chapter(SUMMARY_CHAPTER);
-        let summary = Summary {
-            tenantid,
-            timelineid,
-            seg,
-
-            lsn,
-        };
-        Summary::ser_into(&summary, &mut chapter)?;
-        let book = chapter.close()?;
-
-        // This flushes the underlying 'buf_writer'.
        book.close()?;

        trace!("saved {}", &path.display());
@@ -397,31 +354,6 @@ impl ImageLayer {

        let (path, book) = self.open_book()?;

-        match &self.path_or_conf {
-            PathOrConf::Conf(_) => {
-                let chapter = book.read_chapter(SUMMARY_CHAPTER)?;
-                let actual_summary = Summary::des(&chapter)?;
-
-                let expected_summary = Summary::from(self);
-
-                if actual_summary != expected_summary {
-                    bail!("in-file summary does not match expected summary. actual = {:?} expected = {:?}", actual_summary, expected_summary);
-                }
-            }
-            PathOrConf::Path(path) => {
-                let actual_filename = Path::new(path.file_name().unwrap());
-                let expected_filename = self.filename();
-
-                if actual_filename != expected_filename {
-                    println!(
-                        "warning: filename does not match what is expected from in-file summary"
-                    );
-                    println!("actual: {:?}", actual_filename);
-                    println!("expected: {:?}", expected_filename);
-                }
-            }
-        }
-
        let image_type = if self.seg.rel.is_blocky() {
            let chapter = book.chapter_reader(BLOCKY_IMAGES_CHAPTER)?;
            let images_len = chapter.len();
@@ -483,20 +415,22 @@ impl ImageLayer {
    /// Create an ImageLayer struct representing an existing file on disk.
    ///
    /// This variant is only used for debugging purposes, by the 'dump_layerfile' binary.
-    pub fn new_for_path(path: &Path, book: &Book<File>) -> Result<ImageLayer> {
-        let chapter = book.read_chapter(SUMMARY_CHAPTER)?;
-        let summary = Summary::des(&chapter)?;
-
-        Ok(ImageLayer {
+    pub fn new_for_path(
+        path: &Path,
+        timelineid: ZTimelineId,
+        tenantid: ZTenantId,
+        filename: &ImageFileName,
+    ) -> ImageLayer {
+        ImageLayer {
            path_or_conf: PathOrConf::Path(path.to_path_buf()),
-            timelineid: summary.timelineid,
-            tenantid: summary.tenantid,
-            seg: summary.seg,
-            lsn: summary.lsn,
+            timelineid,
+            tenantid,
+            seg: filename.seg,
+            lsn: filename.lsn,
            inner: Mutex::new(ImageLayerInner {
                loaded: false,
                image_type: ImageType::Blocky { num_blocks: 0 },
            }),
-        })
+        }
    }
 }
--- a/pageserver/src/layered_repository/inmemory_layer.rs
+++ b/pageserver/src/layered_repository/inmemory_layer.rs
@@ -7,7 +7,6 @@ use crate::layered_repository::storage_layer::{
    Layer, PageReconstructData, PageReconstructResult, PageVersion, SegmentTag, RELISH_SEG_SIZE,
 };
 use crate::layered_repository::LayeredTimeline;
-use crate::layered_repository::ZERO_PAGE;
 use crate::layered_repository::{DeltaLayer, ImageLayer};
 use crate::repository::WALRecord;
 use crate::PageServerConf;
@@ -15,13 +14,11 @@ use crate::{ZTenantId, ZTimelineId};
 use anyhow::{bail, Result};
 use bytes::Bytes;
 use log::*;
-use std::cmp::min;
 use std::collections::BTreeMap;
 use std::ops::Bound::Included;
 use std::path::PathBuf;
-use std::sync::{Arc, RwLock};
+use std::sync::{Arc, Mutex};

-use zenith_utils::accum::Accum;
 use zenith_utils::lsn::Lsn;

 pub struct InMemoryLayer {
@@ -32,19 +29,20 @@ pub struct InMemoryLayer {

    ///
    /// This layer contains all the changes from 'start_lsn'. The
-    /// start is inclusive.
+    /// start is inclusive. There is no end LSN; we only use in-memory
+    /// layer at the end of a timeline.
    ///
    start_lsn: Lsn,

-    /// Frozen in-memory layers have an inclusive end LSN.
-    end_lsn: Option<Lsn>,
-
    /// LSN of the oldest page version stored in this layer
    oldest_pending_lsn: Lsn,

    /// The above fields never change. The parts that do change are in 'inner',
    /// and protected by mutex.
-    inner: RwLock<InMemoryLayerInner>,
+    inner: Mutex<InMemoryLayerInner>,
+
+    /// Predecessor layer
+    predecessor: Option<Arc<dyn Layer>>,
 }

 pub struct InMemoryLayerInner {
@@ -61,24 +59,9 @@ pub struct InMemoryLayerInner {
    /// `segsizes` tracks the size of the segment at different points in time.
    ///
    segsizes: BTreeMap<Lsn, u32>,
-
-    /// Writes are only allowed when true.
-    /// Set to false when this layer is in the process of being replaced.
-    writeable: bool,
-
-    /// Predecessor layer
-    predecessor: Option<Arc<dyn Layer>>,
 }

 impl InMemoryLayerInner {
-    fn check_writeable(&self) -> WriteResult<()> {
-        if self.writeable {
-            Ok(())
-        } else {
-            Err(NonWriteableError)
-        }
-    }
-
    fn get_seg_size(&self, lsn: Lsn) -> u32 {
        // Scan the BTreeMap backwards, starting from the given entry.
        let mut iter = self.segsizes.range((Included(&Lsn(0)), Included(&lsn)));
@@ -95,7 +78,7 @@ impl Layer for InMemoryLayer {
    // An in-memory layer doesn't really have a filename as it's not stored on disk,
    // but we construct a filename as if it was a delta layer
    fn filename(&self) -> PathBuf {
-        let inner = self.inner.read().unwrap();
+        let inner = self.inner.lock().unwrap();

        let end_lsn;
        let dropped;
@@ -110,36 +93,28 @@ impl Layer for InMemoryLayer {
        let delta_filename = DeltaFileName {
            seg: self.seg,
            start_lsn: self.start_lsn,
-            end_lsn,
-            dropped,
+            end_lsn: end_lsn,
+            dropped: dropped,
        }
        .to_string();

        PathBuf::from(format!("inmem-{}", delta_filename))
    }

-    fn path(&self) -> Option<PathBuf> {
-        None
-    }
-
    fn get_timeline_id(&self) -> ZTimelineId {
-        self.timelineid
+        return self.timelineid;
    }

    fn get_seg_tag(&self) -> SegmentTag {
-        self.seg
+        return self.seg;
    }

    fn get_start_lsn(&self) -> Lsn {
-        self.start_lsn
+        return self.start_lsn;
    }

    fn get_end_lsn(&self) -> Lsn {
-        if let Some(end_lsn) = self.end_lsn {
-            return Lsn(end_lsn.0 + 1);
-        }
-
-        let inner = self.inner.read().unwrap();
+        let inner = self.inner.lock().unwrap();

        if let Some(drop_lsn) = inner.drop_lsn {
            drop_lsn
@@ -149,7 +124,7 @@ impl Layer for InMemoryLayer {
    }

    fn is_dropped(&self) -> bool {
-        let inner = self.inner.read().unwrap();
+        let inner = self.inner.lock().unwrap();
        inner.drop_lsn.is_some()
    }

@@ -160,14 +135,12 @@ impl Layer for InMemoryLayer {
        lsn: Lsn,
        reconstruct_data: &mut PageReconstructData,
    ) -> Result<PageReconstructResult> {
-        let mut need_image = true;
+        let mut cont_lsn: Option<Lsn> = Some(lsn);

        assert!(self.seg.blknum_in_seg(blknum));

-        let predecessor: Option<Arc<dyn Layer>>;
-
        {
-            let inner = self.inner.read().unwrap();
+            let inner = self.inner.lock().unwrap();

            // Scan the BTreeMap backwards, starting from reconstruct_data.lsn.
            let minkey = (blknum, Lsn(0));
@@ -175,17 +148,20 @@ impl Layer for InMemoryLayer {
            let mut iter = inner
                .page_versions
                .range((Included(&minkey), Included(&maxkey)));
-            while let Some(((_blknum, _entry_lsn), entry)) = iter.next_back() {
+            while let Some(((_blknum, entry_lsn), entry)) = iter.next_back() {
                if let Some(img) = &entry.page_image {
                    reconstruct_data.page_img = Some(img.clone());
-                    need_image = false;
+                    cont_lsn = None;
                    break;
                } else if let Some(rec) = &entry.record {
                    reconstruct_data.records.push(rec.clone());
                    if rec.will_init {
                        // This WAL record initializes the page, so no need to go further back
-                        need_image = false;
+                        cont_lsn = None;
                        break;
+                    } else {
+                        // This WAL record needs to be applied against an older page image
+                        cont_lsn = Some(*entry_lsn);
                    }
                } else {
                    // No base image, and no WAL record. Huh?
@@ -193,17 +169,19 @@ impl Layer for InMemoryLayer {
                }
            }

-            predecessor = inner.predecessor.clone();
            // release lock on 'inner'
        }

        // If an older page image is needed to reconstruct the page, let the
        // caller know about the predecessor layer.
-        if need_image {
-            if let Some(cont_layer) = predecessor {
-                Ok(PageReconstructResult::Continue(self.start_lsn, cont_layer))
+        if let Some(cont_lsn) = cont_lsn {
+            if let Some(cont_layer) = &self.predecessor {
+                Ok(PageReconstructResult::Continue(
+                    cont_lsn,
+                    Arc::clone(cont_layer),
+                ))
            } else {
-                Ok(PageReconstructResult::Missing(self.start_lsn))
+                Ok(PageReconstructResult::Missing(cont_lsn))
            }
        } else {
            Ok(PageReconstructResult::Complete)
@@ -214,19 +192,16 @@ impl Layer for InMemoryLayer {
    fn get_seg_size(&self, lsn: Lsn) -> Result<u32> {
        assert!(lsn >= self.start_lsn);

-        let inner = self.inner.read().unwrap();
+        let inner = self.inner.lock().unwrap();
        Ok(inner.get_seg_size(lsn))
    }

    /// Does this segment exist at given LSN?
    fn get_seg_exists(&self, lsn: Lsn) -> Result<bool> {
-        let inner = self.inner.read().unwrap();
-
-        // If the segment created after requested LSN,
-        // it doesn't exist in the layer. But we shouldn't
-        // have requested it in the first place.
        assert!(lsn >= self.start_lsn);

+        let inner = self.inner.lock().unwrap();
+
        // Is the requested LSN after the segment was dropped?
        if let Some(drop_lsn) = inner.drop_lsn {
            if lsn >= drop_lsn {
@@ -252,13 +227,12 @@ impl Layer for InMemoryLayer {
    }

    fn is_incremental(&self) -> bool {
-        let inner = self.inner.read().unwrap();
-        inner.predecessor.is_some()
+        self.predecessor.is_some()
    }

    /// debugging function to print out the contents of the layer
    fn dump(&self) -> Result<()> {
-        let inner = self.inner.read().unwrap();
+        let inner = self.inner.lock().unwrap();

        let end_str = inner
            .drop_lsn
@@ -272,43 +246,17 @@ impl Layer for InMemoryLayer {
        );

        for (k, v) in inner.segsizes.iter() {
-            println!("segsizes {}: {}", k, v);
-        }
-
-        for (k, v) in inner.page_versions.iter() {
-            println!(
-                "blk {} at {}: {}/{}\n",
-                k.0,
-                k.1,
-                v.page_image.is_some(),
-                v.record.is_some()
-            );
+            println!("{}: {}", k, v);
        }
+        //for (k, v) in inner.page_versions.iter() {
+        //    println!("blk {} at {}: {}/{}", k.0, k.1, v.page_image.is_some(), v.record.is_some());
+        //}

        Ok(())
    }
 }

-/// Write failed because the layer is in process of being replaced.
-/// See [`LayeredTimeline::perform_write_op`] for how to handle this error.
-#[derive(Debug)]
-pub struct NonWriteableError;
-
-pub type WriteResult<T> = std::result::Result<T, NonWriteableError>;
-
-/// Helper struct to cleanup `InMemoryLayer::freeze` return signature.
-pub struct FreezeLayers {
-    /// Replacement layer for the layer which freeze was called on.
-    pub frozen: Arc<InMemoryLayer>,
-    /// New open layer containing leftover data.
-    pub open: Option<Arc<InMemoryLayer>>,
-}
-
 impl InMemoryLayer {
-    fn assert_not_frozen(&self) {
-        assert!(self.end_lsn.is_none());
-    }
-
    /// Return the oldest page version that's stored in this layer
    pub fn get_oldest_pending_lsn(&self) -> Lsn {
        self.oldest_pending_lsn
@@ -325,7 +273,7 @@ impl InMemoryLayer {
        start_lsn: Lsn,
        oldest_pending_lsn: Lsn,
    ) -> Result<InMemoryLayer> {
-        trace!(
+        println!(
            "initializing new empty InMemoryLayer for writing {} on timeline {} at {}",
            seg,
            timelineid,
@@ -338,22 +286,20 @@ impl InMemoryLayer {
            tenantid,
            seg,
            start_lsn,
-            end_lsn: None,
            oldest_pending_lsn,
-            inner: RwLock::new(InMemoryLayerInner {
+            inner: Mutex::new(InMemoryLayerInner {
                drop_lsn: None,
                page_versions: BTreeMap::new(),
                segsizes: BTreeMap::new(),
-                writeable: true,
-                predecessor: None,
            }),
+            predecessor: None,
        })
    }

    // Write operations

    /// Remember new page version, as a WAL record over previous version
-    pub fn put_wal_record(&self, blknum: u32, rec: WALRecord) -> WriteResult<u32> {
+    pub fn put_wal_record(&self, blknum: u32, rec: WALRecord) -> Result<()> {
        self.put_page_version(
            blknum,
            rec.lsn,
@@ -365,7 +311,7 @@ impl InMemoryLayer {
    }

    /// Remember new page version, as a full page image
-    pub fn put_page_image(&self, blknum: u32, lsn: Lsn, img: Bytes) -> WriteResult<u32> {
+    pub fn put_page_image(&self, blknum: u32, lsn: Lsn, img: Bytes) -> Result<()> {
        self.put_page_version(
            blknum,
            lsn,
@@ -378,20 +324,17 @@ impl InMemoryLayer {

    /// Common subroutine of the public put_wal_record() and put_page_image() functions.
    /// Adds the page version to the in-memory tree
-    pub fn put_page_version(&self, blknum: u32, lsn: Lsn, pv: PageVersion) -> WriteResult<u32> {
-        self.assert_not_frozen();
+    pub fn put_page_version(&self, blknum: u32, lsn: Lsn, pv: PageVersion) -> Result<()> {
        assert!(self.seg.blknum_in_seg(blknum));

-        trace!(
+        println!(
            "put_page_version blk {} of {} at {}/{}",
            blknum,
            self.seg.rel,
            self.timelineid,
            lsn
        );
-        let mut inner = self.inner.write().unwrap();
-
-        inner.check_writeable()?;
+        let mut inner = self.inner.lock().unwrap();

        let old = inner.page_versions.insert((blknum, lsn), pv);

@@ -407,66 +350,27 @@ impl InMemoryLayer {
        if self.seg.rel.is_blocky() {
            let newsize = blknum - self.seg.segno * RELISH_SEG_SIZE + 1;

-            // use inner get_seg_size, since calling self.get_seg_size will try to acquire the lock,
+            // use inner get_seg_size, since calling self.get_seg_size will try to acquire self.inner.lock
            // which we've just acquired above
            let oldsize = inner.get_seg_size(lsn);
            if newsize > oldsize {
-                trace!(
+                println!(
                    "enlarging segment {} from {} to {} blocks at {}",
                    self.seg,
                    oldsize,
                    newsize,
                    lsn
                );
-
-                // If we are extending the relation by more than one page, initialize the "gap"
-                // with zeros
-                //
-                // XXX: What if the caller initializes the gap with subsequent call with same LSN?
-                // I don't think that can happen currently, but that is highly dependent on how
-                // PostgreSQL writes its WAL records and there's no guarantee of it. If it does
-                // happen, we would hit the "page version already exists" warning above on the
-                // subsequent call to initialize the gap page.
-                let gapstart = self.seg.segno * RELISH_SEG_SIZE + oldsize;
-                for gapblknum in gapstart..blknum {
-                    let zeropv = PageVersion {
-                        page_image: Some(ZERO_PAGE.clone()),
-                        record: None,
-                    };
-                    trace!(
-                        "filling gap blk {} with zeros for write of {}",
-                        gapblknum,
-                        blknum
-                    );
-                    let old = inner.page_versions.insert((gapblknum, lsn), zeropv);
-                    // We already had an entry for this LSN. That's odd..
-
-                    if old.is_some() {
-                        warn!(
-                            "Page version of rel {} blk {} at {} already exists",
-                            self.seg.rel, blknum, lsn
-                        );
-                    }
-                }
-
                inner.segsizes.insert(lsn, newsize);
-                return Ok(newsize - oldsize);
            }
        }
-        Ok(0)
+
+        Ok(())
    }

    /// Remember that the relation was truncated at given LSN
-    pub fn put_truncation(&self, lsn: Lsn, segsize: u32) -> WriteResult<()> {
-        self.assert_not_frozen();
-
-        let mut inner = self.inner.write().unwrap();
-        inner.check_writeable()?;
-
-        // check that this we truncate to a smaller size than segment was before the truncation
-        let oldsize = inner.get_seg_size(lsn);
-        assert!(segsize < oldsize);
-
+    pub fn put_truncation(&self, lsn: Lsn, segsize: u32) -> anyhow::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
        let old = inner.segsizes.insert(lsn, segsize);

        if old.is_some() {
@@ -478,18 +382,41 @@ impl InMemoryLayer {
    }

    /// Remember that the segment was dropped at given LSN
-    pub fn drop_segment(&self, lsn: Lsn) -> WriteResult<()> {
-        self.assert_not_frozen();
-
-        let mut inner = self.inner.write().unwrap();
-
-        inner.check_writeable()?;
+    pub fn drop_segment(&self, lsn: Lsn) -> anyhow::Result<()> {
+        let mut inner = self.inner.lock().unwrap();

        assert!(inner.drop_lsn.is_none());
        inner.drop_lsn = Some(lsn);
-        inner.writeable = false;

-        trace!("dropped segment {} at {}", self.seg, lsn);
+        println!("dropped segment {} at {}", self.seg, lsn);
+
+        let end_str = inner
+        .drop_lsn
+        .as_ref()
+        .map(|drop_lsn| drop_lsn.to_string())
+        .unwrap_or_default();
+
+        {
+            let mut result = format!(
+                "----- inmemory layer tli {} for {} {}-{} ----\n",
+                self.timelineid, self.seg, self.start_lsn, end_str
+            );
+
+            for (k, v) in inner.segsizes.iter() {
+                result += &format!("{}: {}\n", k, v);
+            }
+            for (k, v) in inner.page_versions.iter() {
+                result += &format!(
+                    "blk {} at {}: {}/{}\n",
+                    k.0,
+                    k.1,
+                    v.page_image.is_some(),
+                    v.record.is_some()
+                );
+            }
+
+            println!("{}", result);
+        }

        Ok(())
    }
@@ -508,10 +435,7 @@ impl InMemoryLayer {
    ) -> Result<InMemoryLayer> {
        let seg = src.get_seg_tag();

-        assert!(oldest_pending_lsn.is_aligned());
-        assert!(oldest_pending_lsn >= start_lsn);
-
-        trace!(
+        println!(
            "initializing new InMemoryLayer for writing {} on timeline {} at {}",
            seg,
            timelineid,
@@ -531,191 +455,93 @@ impl InMemoryLayer {
            tenantid,
            seg,
            start_lsn,
-            end_lsn: None,
            oldest_pending_lsn,
-            inner: RwLock::new(InMemoryLayerInner {
+            inner: Mutex::new(InMemoryLayerInner {
                drop_lsn: None,
                page_versions: BTreeMap::new(),
-                segsizes,
-                writeable: true,
-                predecessor: Some(src),
+                segsizes: segsizes,
            }),
+            predecessor: Some(src),
        })
    }

-    pub fn is_writeable(&self) -> bool {
-        let inner = self.inner.read().unwrap();
-        inner.writeable
-    }
-
-    /// Splits `self` into two InMemoryLayers: `frozen` and `open`.
-    /// All data up to and including `cutoff_lsn`
-    /// is copied to `frozen`, while the remaining data is copied to `open`.
-    /// After completion, self is non-writeable, but not frozen.
-    pub fn freeze(self: Arc<Self>, cutoff_lsn: Lsn) -> Result<FreezeLayers> {
-        info!(
-            "freezing in memory layer {} on timeline {} at {} (oldest {})",
-            self.filename().display(),
-            self.timelineid,
-            cutoff_lsn,
-            self.oldest_pending_lsn
+    ///
+    /// Write the this in-memory layer to disk.
+    ///
+    /// The cutoff point for the layer that's written to disk is 'end_lsn'.
+    ///
+    /// Returns new layers that replace this one. Always returns a new image
+    /// layer containing the page versions at the cutoff LSN, that were written
+    /// to disk, and usually also a DeltaLayer that includes all the WAL records
+    /// between start LSN and the cutoff. (The delta layer is not needed when
+    /// a new relish is created with a single LSN, so that the start and end LSN
+    /// are the same.) If there were page versions newer than 'end_lsn', also
+    /// returns a new in-memory layer containing those page versions. The caller
+    /// replaces this layer with the returned layers in the layer map.
+    ///
+    pub fn freeze(
+        &self,
+        cutoff_lsn: Lsn,
+        // This is needed just to call materialize_page()
+        timeline: &LayeredTimeline,
+    ) -> Result<(Vec<Arc<dyn Layer>>, Option<Arc<InMemoryLayer>>)> {
+        println!(
+            "freezing in memory layer for {} on timeline {} at {}",
+            self.seg, self.timelineid, cutoff_lsn
        );

-        self.assert_not_frozen();
+        let inner = self.inner.lock().unwrap();

-        let self_ref = self.clone();
-        let mut inner = self_ref.inner.write().unwrap();
-        // Dropped layers don't need any special freeze actions,
-        // they are marked as non-writeable at drop and just
-        // written out to disk by checkpointer.
-        if inner.drop_lsn.is_some() {
-            assert!(!inner.writeable);
-            info!(
-                "freezing in memory layer for {} on timeline {} is dropped at {}",
-                self.seg,
-                self.timelineid,
-                inner.drop_lsn.unwrap()
-            );
-
-            // There should be no newer layer that refers this non-writeable layer,
-            // because layer that is created after dropped one represents a new rel.
-            return Ok(FreezeLayers {
-                frozen: self,
-                open: None,
-            });
-        }
-        assert!(inner.writeable);
-        inner.writeable = false;
-
-        // Divide all the page versions into old and new
-        // at the 'cutoff_lsn' point.
-        let mut before_segsizes = BTreeMap::new();
-        let mut after_segsizes = BTreeMap::new();
-        let mut after_oldest_lsn: Accum<Lsn> = Accum(None);
-        for (lsn, size) in inner.segsizes.iter() {
-            if *lsn > cutoff_lsn {
-                after_segsizes.insert(*lsn, *size);
-                after_oldest_lsn.accum(min, *lsn);
-            } else {
-                before_segsizes.insert(*lsn, *size);
-            }
-        }
-
-        let mut before_page_versions = BTreeMap::new();
-        let mut after_page_versions = BTreeMap::new();
-        for ((blknum, lsn), pv) in inner.page_versions.iter() {
-            if *lsn > cutoff_lsn {
-                after_page_versions.insert((*blknum, *lsn), pv.clone());
-                after_oldest_lsn.accum(min, *lsn);
-            } else {
-                before_page_versions.insert((*blknum, *lsn), pv.clone());
-            }
-        }
-
-        let frozen = Arc::new(InMemoryLayer {
-            conf: self.conf,
-            tenantid: self.tenantid,
-            timelineid: self.timelineid,
-            seg: self.seg,
-            start_lsn: self.start_lsn,
-            end_lsn: Some(cutoff_lsn),
-            oldest_pending_lsn: self.start_lsn,
-            inner: RwLock::new(InMemoryLayerInner {
-                drop_lsn: inner.drop_lsn,
-                page_versions: before_page_versions,
-                segsizes: before_segsizes,
-                writeable: false,
-                predecessor: inner.predecessor.clone(),
-            }),
-        });
-
-        let open = if !after_segsizes.is_empty() || !after_page_versions.is_empty() {
-            let mut new_open = Self::create_successor_layer(
-                self.conf,
-                frozen.clone(),
-                self.timelineid,
-                self.tenantid,
-                cutoff_lsn + 1,
-                after_oldest_lsn.0.unwrap(),
-            )?;
-
-            let new_inner = new_open.inner.get_mut().unwrap();
-            new_inner.page_versions.append(&mut after_page_versions);
-            new_inner.segsizes.append(&mut after_segsizes);
-
-            Some(Arc::new(new_open))
+        // Normally, use the cutoff LSN as the end of the frozen layer.
+        // But if the relation was dropped, we know that there are no
+        // more changes coming in for it, and in particular we know that
+        // there are no changes "in flight" for the LSN anymore, so we use
+        // the drop LSN instead. The drop-LSN could be ahead of the
+        // caller-specified LSN!
+        let dropped = inner.drop_lsn.is_some();
+        let end_lsn = if dropped {
+            inner.drop_lsn.unwrap()
        } else {
-            None
+            cutoff_lsn
        };

-        Ok(FreezeLayers { frozen, open })
-    }
-
-    /// Write the this frozen in-memory layer to disk.
-    ///
-    /// Returns new layers that replace this one.
-    /// If not dropped, returns a new image layer containing the page versions
-    /// at the `end_lsn`. Can also return a DeltaLayer that includes all the
-    /// WAL records between start and end LSN. (The delta layer is not needed
-    /// when a new relish is created with a single LSN, so that the start and
-    /// end LSN are the same.)
-    pub fn write_to_disk(&self, timeline: &LayeredTimeline) -> Result<Vec<Arc<dyn Layer>>> {
-        trace!(
-            "write_to_disk {} end_lsn is {} get_end_lsn is {}",
-            self.filename().display(),
-            self.end_lsn.unwrap_or(Lsn(0)),
-            self.get_end_lsn()
-        );
-
-        // Grab the lock in read-mode. We hold it over the I/O, but because this
-        // layer is not writeable anymore, no one should be trying to aquire the
-        // write lock on it, so we shouldn't block anyone. There's one exception
-        // though: another thread might have grabbed a reference to this layer
-        // in `get_layer_for_write' just before the checkpointer called
-        // `freeze`, and then `write_to_disk` on it. When the thread gets the
-        // lock, it will see that it's not writeable anymore and retry, but it
-        // would have to wait until we release it. That race condition is very
-        // rare though, so we just accept the potential latency hit for now.
-        let inner = self.inner.read().unwrap();
-        assert!(!inner.writeable);
-
-        let predecessor = inner.predecessor.clone();
-
-        if let Some(drop_lsn) = inner.drop_lsn {
-            let delta_layer = DeltaLayer::create(
-                self.conf,
-                self.timelineid,
-                self.tenantid,
-                self.seg,
-                self.start_lsn,
-                drop_lsn,
-                true,
-                predecessor,
-                inner.page_versions.iter(),
-                inner.segsizes.clone(),
-            )?;
-            trace!(
-                "freeze: created delta layer for dropped segment {} {}-{}",
-                self.seg,
-                self.start_lsn,
-                drop_lsn
-            );
-            return Ok(vec![Arc::new(delta_layer)]);
-        }
-
-        let end_lsn = self.end_lsn.unwrap();
-
-        let mut before_segsizes = BTreeMap::new();
-        for (lsn, size) in inner.segsizes.iter() {
-            if *lsn <= end_lsn {
-                before_segsizes.insert(*lsn, *size);
+        // Divide all the page versions into old and new at the 'end_lsn' cutoff point.
+        let mut before_page_versions;
+        let mut before_segsizes;
+        let mut after_page_versions;
+        let mut after_segsizes;
+        if !dropped {
+            before_segsizes = BTreeMap::new();
+            after_segsizes = BTreeMap::new();
+            for (lsn, size) in inner.segsizes.iter() {
+                if *lsn > end_lsn {
+                    after_segsizes.insert(*lsn, *size);
+                } else {
+                    before_segsizes.insert(*lsn, *size);
+                }
            }
-        }
-        let mut before_page_versions = inner.page_versions.iter().filter(|tup| {
-            let ((_blknum, lsn), _pv) = tup;

-            *lsn < end_lsn
-        });
+            before_page_versions = BTreeMap::new();
+            after_page_versions = BTreeMap::new();
+            for ((blknum, lsn), pv) in inner.page_versions.iter() {
+                if *lsn == end_lsn {
+                    // Page versions at the cutoff LSN will be stored in the
+                    // materialized image layer.
+                } else if *lsn > end_lsn {
+                    after_page_versions.insert((*blknum, *lsn), pv.clone());
+                } else {
+                    before_page_versions.insert((*blknum, *lsn), pv.clone());
+                }
+            }
+        } else {
+            before_page_versions = inner.page_versions.clone();
+            before_segsizes = inner.segsizes.clone();
+            after_segsizes = BTreeMap::new();
+            after_page_versions = BTreeMap::new();
+        }
+
+        // we can release the lock now.
+        drop(inner);

        let mut frozen_layers: Vec<Arc<dyn Layer>> = Vec::new();

@@ -728,34 +554,89 @@ impl InMemoryLayer {
                self.seg,
                self.start_lsn,
                end_lsn,
-                false,
-                predecessor,
+                dropped,
+                self.predecessor.clone(),
                before_page_versions,
                before_segsizes,
            )?;
-            frozen_layers.push(Arc::new(delta_layer));
-            trace!(
+            let delta_layer_rc: Arc<dyn Layer> = Arc::new(delta_layer);
+            frozen_layers.push(delta_layer_rc);
+            println!(
                "freeze: created delta layer {} {}-{}",
                self.seg,
                self.start_lsn,
                end_lsn
            );
        } else {
-            assert!(before_page_versions.next().is_none());
+            assert!(before_page_versions.is_empty());
        }

-        drop(inner);
+        let mut new_open_rc = None;
+        if !dropped {
+            // Write a new base image layer at the cutoff point
+            let imgfile = ImageLayer::create_from_src(self.conf, timeline, self, end_lsn)?;
+            let imgfile_rc: Arc<dyn Layer> = Arc::new(imgfile);
+            frozen_layers.push(Arc::clone(&imgfile_rc));
+            println!("freeze: created image layer {} at {}", self.seg, end_lsn);

-        // Write a new base image layer at the cutoff point
-        let image_layer = ImageLayer::create_from_src(self.conf, timeline, self, end_lsn)?;
-        frozen_layers.push(Arc::new(image_layer));
-        trace!("freeze: created image layer {} at {}", self.seg, end_lsn);
+            // If there were any page versions newer than the cutoff, initialize a new in-memory
+            // layer to hold them
+            if !after_segsizes.is_empty() || !after_page_versions.is_empty() {
+                let new_open = Self::create_successor_layer(
+                    self.conf,
+                    imgfile_rc,
+                    self.timelineid,
+                    self.tenantid,
+                    end_lsn,
+                    end_lsn,
+                )?;
+                let mut new_inner = new_open.inner.lock().unwrap();
+                new_inner.page_versions.append(&mut after_page_versions);
+                new_inner.segsizes.append(&mut after_segsizes);
+                drop(new_inner);
+                println!("freeze: created new in-mem layer {} {}-", self.seg, end_lsn);

-        Ok(frozen_layers)
+                new_open_rc = Some(Arc::new(new_open))
+            }
+        }
+
+        Ok((frozen_layers, new_open_rc))
    }

-    pub fn update_predecessor(&self, predecessor: Arc<dyn Layer>) -> Option<Arc<dyn Layer>> {
-        let mut inner = self.inner.write().unwrap();
-        inner.predecessor.replace(predecessor)
+    /// debugging function to print out the contents of the layer
+    #[allow(unused)]
+    pub fn dump(&self) -> String {
+
+
+        let inner = self.inner.lock().unwrap();
+
+        let end_str = inner
+        .drop_lsn
+        .as_ref()
+        .map(|drop_lsn| drop_lsn.to_string())
+        .unwrap_or_default();
+
+        let mut result =  format!(
+            "----- dump inmemory layer for tli {} seg {} {}-{} ----",
+            self.timelineid, self.seg, self.start_lsn, end_str
+        );
+
+
+        for (k, v) in inner.segsizes.iter() {
+            result += &format!("{}: {}\n", k, v);
+        }
+        for (k, v) in inner.page_versions.iter() {
+            result += &format!(
+                "blk {} at {}: {}/{}\n",
+                k.0,
+                k.1,
+                v.page_image.is_some(),
+                v.record.is_some()
+            );
+        }
+
+        println!("inner println {}", result);
+        result
+
    }
 }
--- a/pageserver/src/layered_repository/interval_tree.rs
+++ b/pageserver/src/layered_repository/interval_tree.rs
@@ -1,471 +0,0 @@
-///
-/// IntervalTree is data structure for holding intervals. It is generic
-/// to make unit testing possible, but the only real user of it is the layer map,
-///
-/// It's inspired by the "segment tree" or a "statistic tree" as described in
-/// https://en.wikipedia.org/wiki/Segment_tree. However, we use a B-tree to hold
-/// the points instead of a binary tree. This is called an "interval tree" instead
-/// of "segment tree" because the term "segment" is already using Zenith to mean
-/// something else. To add to the confusion, there is another data structure known
-/// as "interval tree" out there (see https://en.wikipedia.org/wiki/Interval_tree),
-/// for storing intervals, but this isn't that.
-///
-/// The basic idea is to have a B-tree of "interesting Points". At each Point,
-/// there is a list of intervals that contain the point. The Points are formed
-/// from the start bounds of each interval; there is a Point for each distinct
-/// start bound.
-///
-/// Operations:
-///
-/// To find intervals that contain a given point, you search the b-tree to find
-/// the nearest Point <= search key. Then you just return the list of intervals.
-///
-/// To insert an interval, find the Point with start key equal to the inserted item.
-/// If the Point doesn't exist yet, create it, by copying all the items from the
-/// previous Point that cover the new Point. Then walk right, inserting the new
-/// interval to all the Points that are contained by the new interval (including the
-/// newly created Point).
-///
-/// To remove an interval, you scan the tree for all the Points that are contained by
-/// the removed interval, and remove it from the list in each Point.
-///
-/// Requirements and assumptions:
-///
-/// - Can store overlapping items
-/// - But there are not many overlapping items
-/// - The interval bounds don't change after it is added to the tree
-/// - Intervals are uniquely identified by pointer equality. You must not be insert the
-///   same interval object twice, and `remove` uses pointer equality to remove the right
-///   interval. It is OK to have two intervals with the same bounds, however.
-///
-use std::collections::BTreeMap;
-use std::fmt::Debug;
-use std::ops::Range;
-use std::sync::Arc;
-
-pub struct IntervalTree<I: ?Sized>
-where
-    I: IntervalItem,
-{
-    points: BTreeMap<I::Key, Point<I>>,
-}
-
-struct Point<I: ?Sized> {
-    /// All intervals that contain this point, in no particular order.
-    ///
-    /// We assume that there aren't a lot of overlappingg intervals, so that this vector
-    /// never grows very large. If that assumption doesn't hold, we could keep this ordered
-    /// by the end bound, to speed up `search`. But as long as there are only a few elements,
-    /// a linear search is OK.
-    elements: Vec<Arc<I>>,
-}
-
-/// Abstraction for an interval that can be stored in the tree
-///
-/// The start bound is inclusive and the end bound is exclusive. End must be greater
-/// than start.
-pub trait IntervalItem {
-    type Key: Ord + Copy + Debug + Sized;
-
-    fn start_key(&self) -> Self::Key;
-    fn end_key(&self) -> Self::Key;
-
-    fn bounds(&self) -> Range<Self::Key> {
-        self.start_key()..self.end_key()
-    }
-}
-
-impl<I: ?Sized> IntervalTree<I>
-where
-    I: IntervalItem,
-{
-    /// Return an element that contains 'key', or precedes it.
-    ///
-    /// If there are multiple candidates, returns the one with the highest 'end' key.
-    pub fn search(&self, key: I::Key) -> Option<Arc<I>> {
-        // Find the greatest point that precedes or is equal to the search key. If there is
-        // none, returns None.
-        let (_, p) = self.points.range(..=key).next_back()?;
-
-        // Find the element with the highest end key at this point
-        let highest_item = p
-            .elements
-            .iter()
-            .reduce(|a, b| {
-                // starting with Rust 1.53, could use `std::cmp::min_by_key` here
-                if a.end_key() > b.end_key() {
-                    a
-                } else {
-                    b
-                }
-            })
-            .unwrap();
-        Some(Arc::clone(highest_item))
-    }
-
-    /// Iterate over all items with start bound >= 'key'
-    pub fn iter_newer(&self, key: I::Key) -> IntervalIter<I> {
-        IntervalIter {
-            point_iter: self.points.range(key..),
-            elem_iter: None,
-        }
-    }
-
-    /// Iterate over all items
-    pub fn iter(&self) -> IntervalIter<I> {
-        IntervalIter {
-            point_iter: self.points.range(..),
-            elem_iter: None,
-        }
-    }
-
-    pub fn insert(&mut self, item: Arc<I>) {
-        let start_key = item.start_key();
-        let end_key = item.end_key();
-        assert!(start_key < end_key);
-        let bounds = start_key..end_key;
-
-        // Find the starting point and walk forward from there
-        let mut found_start_point = false;
-        let iter = self.points.range_mut(bounds);
-        for (point_key, point) in iter {
-            if *point_key == start_key {
-                found_start_point = true;
-                // It is an error to insert the same item to the tree twice.
-                assert!(
-                    !point.elements.iter().any(|x| Arc::ptr_eq(x, &item)),
-                    "interval is already in the tree"
-                );
-            }
-            point.elements.push(Arc::clone(&item));
-        }
-        if !found_start_point {
-            // Create a new Point for the starting point
-
-            // Look at the previous point, and copy over elements that overlap with this
-            // new point
-            let mut new_elements: Vec<Arc<I>> = Vec::new();
-            if let Some((_, prev_point)) = self.points.range(..start_key).next_back() {
-                let overlapping_prev_elements = prev_point
-                    .elements
-                    .iter()
-                    .filter(|x| x.bounds().contains(&start_key))
-                    .cloned();
-
-                new_elements.extend(overlapping_prev_elements);
-            }
-            new_elements.push(item);
-
-            let new_point = Point {
-                elements: new_elements,
-            };
-            self.points.insert(start_key, new_point);
-        }
-    }
-
-    pub fn remove(&mut self, item: &Arc<I>) {
-        // range search points
-        let start_key = item.start_key();
-        let end_key = item.end_key();
-        let bounds = start_key..end_key;
-
-        let mut points_to_remove: Vec<I::Key> = Vec::new();
-        let mut found_start_point = false;
-        for (point_key, point) in self.points.range_mut(bounds) {
-            if *point_key == start_key {
-                found_start_point = true;
-            }
-            let len_before = point.elements.len();
-            point.elements.retain(|other| !Arc::ptr_eq(other, item));
-            let len_after = point.elements.len();
-            assert_eq!(len_after + 1, len_before);
-            if len_after == 0 {
-                points_to_remove.push(*point_key);
-            }
-        }
-        assert!(found_start_point);
-
-        for k in points_to_remove {
-            self.points.remove(&k).unwrap();
-        }
-    }
-}
-
-pub struct IntervalIter<'a, I: ?Sized>
-where
-    I: IntervalItem,
-{
-    point_iter: std::collections::btree_map::Range<'a, I::Key, Point<I>>,
-    elem_iter: Option<(I::Key, std::slice::Iter<'a, Arc<I>>)>,
-}
-
-impl<'a, I> Iterator for IntervalIter<'a, I>
-where
-    I: IntervalItem + ?Sized,
-{
-    type Item = Arc<I>;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        // Iterate over all elements in all the points in 'point_iter'. To avoid
-        // returning the same element twice, we only return each element at its
-        // starting point.
-        loop {
-            // Return next remaining element from the current point
-            if let Some((point_key, elem_iter)) = &mut self.elem_iter {
-                for elem in elem_iter {
-                    if elem.start_key() == *point_key {
-                        return Some(Arc::clone(elem));
-                    }
-                }
-            }
-            // No more elements at this point. Move to next point.
-            if let Some((point_key, point)) = self.point_iter.next() {
-                self.elem_iter = Some((*point_key, point.elements.iter()));
-                continue;
-            } else {
-                // No more points, all done
-                return None;
-            }
-        }
-    }
-}
-
-impl<I: ?Sized> Default for IntervalTree<I>
-where
-    I: IntervalItem,
-{
-    fn default() -> Self {
-        IntervalTree {
-            points: BTreeMap::new(),
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::fmt;
-
-    #[derive(Debug)]
-    struct MockItem {
-        start_key: u32,
-        end_key: u32,
-        val: String,
-    }
-    impl IntervalItem for MockItem {
-        type Key = u32;
-
-        fn start_key(&self) -> u32 {
-            self.start_key
-        }
-        fn end_key(&self) -> u32 {
-            self.end_key
-        }
-    }
-    impl MockItem {
-        fn new(start_key: u32, end_key: u32) -> Self {
-            MockItem {
-                start_key,
-                end_key,
-                val: format!("{}-{}", start_key, end_key),
-            }
-        }
-        fn new_str(start_key: u32, end_key: u32, val: &str) -> Self {
-            MockItem {
-                start_key,
-                end_key,
-                val: format!("{}-{}: {}", start_key, end_key, val),
-            }
-        }
-    }
-    impl fmt::Display for MockItem {
-        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-            write!(f, "{}", self.val)
-        }
-    }
-    fn assert_search(
-        tree: &IntervalTree<MockItem>,
-        key: u32,
-        expected: &[&str],
-    ) -> Option<Arc<MockItem>> {
-        if let Some(v) = tree.search(key) {
-            let vstr = v.to_string();
-
-            if expected.is_empty() {
-                panic!("search with {} returned {}, expected None", key, v);
-            }
-
-            if !expected.contains(&vstr.as_str()) {
-                panic!(
-                    "search with {} returned {}, expected one of: {:?}",
-                    key, v, expected
-                );
-            }
-            Some(v)
-        } else {
-            if !expected.is_empty() {
-                panic!(
-                    "search with {} returned None, expected one of {:?}",
-                    key, expected
-                );
-            }
-            None
-        }
-    }
-
-    fn assert_contents(tree: &IntervalTree<MockItem>, expected: &[&str]) {
-        let mut contents: Vec<String> = tree.iter().map(|e| e.to_string()).collect();
-        contents.sort();
-        assert_eq!(contents, expected);
-    }
-
-    fn dump_tree(tree: &IntervalTree<MockItem>) {
-        for (point_key, point) in tree.points.iter() {
-            print!("{}:", point_key);
-            for e in point.elements.iter() {
-                print!(" {}", e);
-            }
-            println!();
-        }
-    }
-
-    #[test]
-    fn test_interval_tree_simple() {
-        let mut tree: IntervalTree<MockItem> = IntervalTree::default();
-
-        // Simple, non-overlapping ranges.
-        tree.insert(Arc::new(MockItem::new(10, 11)));
-        tree.insert(Arc::new(MockItem::new(11, 12)));
-        tree.insert(Arc::new(MockItem::new(12, 13)));
-        tree.insert(Arc::new(MockItem::new(18, 19)));
-        tree.insert(Arc::new(MockItem::new(17, 18)));
-        tree.insert(Arc::new(MockItem::new(15, 16)));
-
-        assert_search(&tree, 9, &[]);
-        assert_search(&tree, 10, &["10-11"]);
-        assert_search(&tree, 11, &["11-12"]);
-        assert_search(&tree, 12, &["12-13"]);
-        assert_search(&tree, 13, &["12-13"]);
-        assert_search(&tree, 14, &["12-13"]);
-        assert_search(&tree, 15, &["15-16"]);
-        assert_search(&tree, 16, &["15-16"]);
-        assert_search(&tree, 17, &["17-18"]);
-        assert_search(&tree, 18, &["18-19"]);
-        assert_search(&tree, 19, &["18-19"]);
-        assert_search(&tree, 20, &["18-19"]);
-
-        // remove a few entries and search around them again
-        tree.remove(&assert_search(&tree, 10, &["10-11"]).unwrap()); // first entry
-        tree.remove(&assert_search(&tree, 12, &["12-13"]).unwrap()); // entry in the middle
-        tree.remove(&assert_search(&tree, 18, &["18-19"]).unwrap()); // last entry
-        assert_search(&tree, 9, &[]);
-        assert_search(&tree, 10, &[]);
-        assert_search(&tree, 11, &["11-12"]);
-        assert_search(&tree, 12, &["11-12"]);
-        assert_search(&tree, 14, &["11-12"]);
-        assert_search(&tree, 15, &["15-16"]);
-        assert_search(&tree, 17, &["17-18"]);
-        assert_search(&tree, 18, &["17-18"]);
-    }
-
-    #[test]
-    fn test_interval_tree_overlap() {
-        let mut tree: IntervalTree<MockItem> = IntervalTree::default();
-
-        // Overlapping items
-        tree.insert(Arc::new(MockItem::new(22, 24)));
-        tree.insert(Arc::new(MockItem::new(23, 25)));
-        let x24_26 = Arc::new(MockItem::new(24, 26));
-        tree.insert(Arc::clone(&x24_26));
-        let x26_28 = Arc::new(MockItem::new(26, 28));
-        tree.insert(Arc::clone(&x26_28));
-        tree.insert(Arc::new(MockItem::new(25, 27)));
-
-        assert_search(&tree, 22, &["22-24"]);
-        assert_search(&tree, 23, &["22-24", "23-25"]);
-        assert_search(&tree, 24, &["23-25", "24-26"]);
-        assert_search(&tree, 25, &["24-26", "25-27"]);
-        assert_search(&tree, 26, &["25-27", "26-28"]);
-        assert_search(&tree, 27, &["26-28"]);
-        assert_search(&tree, 28, &["26-28"]);
-        assert_search(&tree, 29, &["26-28"]);
-
-        tree.remove(&x24_26);
-        tree.remove(&x26_28);
-        assert_search(&tree, 23, &["22-24", "23-25"]);
-        assert_search(&tree, 24, &["23-25"]);
-        assert_search(&tree, 25, &["25-27"]);
-        assert_search(&tree, 26, &["25-27"]);
-        assert_search(&tree, 27, &["25-27"]);
-        assert_search(&tree, 28, &["25-27"]);
-        assert_search(&tree, 29, &["25-27"]);
-    }
-
-    #[test]
-    fn test_interval_tree_nested() {
-        let mut tree: IntervalTree<MockItem> = IntervalTree::default();
-
-        // Items containing other items
-        tree.insert(Arc::new(MockItem::new(31, 39)));
-        tree.insert(Arc::new(MockItem::new(32, 34)));
-        tree.insert(Arc::new(MockItem::new(33, 35)));
-        tree.insert(Arc::new(MockItem::new(30, 40)));
-
-        assert_search(&tree, 30, &["30-40"]);
-        assert_search(&tree, 31, &["30-40", "31-39"]);
-        assert_search(&tree, 32, &["30-40", "32-34", "31-39"]);
-        assert_search(&tree, 33, &["30-40", "32-34", "33-35", "31-39"]);
-        assert_search(&tree, 34, &["30-40", "33-35", "31-39"]);
-        assert_search(&tree, 35, &["30-40", "31-39"]);
-        assert_search(&tree, 36, &["30-40", "31-39"]);
-        assert_search(&tree, 37, &["30-40", "31-39"]);
-        assert_search(&tree, 38, &["30-40", "31-39"]);
-        assert_search(&tree, 39, &["30-40"]);
-        assert_search(&tree, 40, &["30-40"]);
-        assert_search(&tree, 41, &["30-40"]);
-    }
-
-    #[test]
-    fn test_interval_tree_duplicates() {
-        let mut tree: IntervalTree<MockItem> = IntervalTree::default();
-
-        // Duplicate keys
-        let item_a = Arc::new(MockItem::new_str(55, 56, "a"));
-        tree.insert(Arc::clone(&item_a));
-        let item_b = Arc::new(MockItem::new_str(55, 56, "b"));
-        tree.insert(Arc::clone(&item_b));
-        let item_c = Arc::new(MockItem::new_str(55, 56, "c"));
-        tree.insert(Arc::clone(&item_c));
-        let item_d = Arc::new(MockItem::new_str(54, 56, "d"));
-        tree.insert(Arc::clone(&item_d));
-        let item_e = Arc::new(MockItem::new_str(55, 57, "e"));
-        tree.insert(Arc::clone(&item_e));
-
-        dump_tree(&tree);
-
-        assert_search(
-            &tree,
-            55,
-            &["55-56: a", "55-56: b", "55-56: c", "54-56: d", "55-57: e"],
-        );
-        tree.remove(&item_b);
-        dump_tree(&tree);
-
-        assert_contents(&tree, &["54-56: d", "55-56: a", "55-56: c", "55-57: e"]);
-
-        tree.remove(&item_d);
-        dump_tree(&tree);
-        assert_contents(&tree, &["55-56: a", "55-56: c", "55-57: e"]);
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_interval_tree_insert_twice() {
-        let mut tree: IntervalTree<MockItem> = IntervalTree::default();
-
-        // Inserting the same item twice is not cool
-        let item = Arc::new(MockItem::new(1, 2));
-        tree.insert(Arc::clone(&item));
-        tree.insert(Arc::clone(&item)); // fails assertion
-    }
-}
--- a/pageserver/src/layered_repository/layer_map.rs
+++ b/pageserver/src/layered_repository/layer_map.rs
@@ -9,14 +9,16 @@
 //! new image and delta layers and corresponding files are written to disk.
 //!

-use crate::layered_repository::interval_tree::{IntervalItem, IntervalIter, IntervalTree};
 use crate::layered_repository::storage_layer::{Layer, SegmentTag};
 use crate::layered_repository::InMemoryLayer;
 use crate::relish::*;
 use anyhow::Result;
 use lazy_static::lazy_static;
+use log::*;
 use std::cmp::Ordering;
-use std::collections::{BinaryHeap, HashMap};
+use std::collections::HashSet;
+use std::collections::{BTreeMap, BinaryHeap, HashMap};
+use std::ops::Bound::Included;
 use std::sync::Arc;
 use zenith_metrics::{register_int_gauge, IntGauge};
 use zenith_utils::lsn::Lsn;
@@ -33,21 +35,68 @@ lazy_static! {
 ///
 /// LayerMap tracks what layers exist on a timeline.
 ///
-#[derive(Default)]
 pub struct LayerMap {
    /// All the layers keyed by segment tag
    segs: HashMap<SegmentTag, SegEntry>,

-    /// All in-memory layers, ordered by 'oldest_pending_lsn' and generation
-    /// of each layer. This allows easy access to the in-memory layer that
-    /// contains the oldest WAL record.
-    open_layers: BinaryHeap<OpenLayerEntry>,
+    /// All in-memory layers, ordered by 'oldest_pending_lsn' of each layer.
+    /// This allows easy access to the in-memory layer that contains the
+    /// oldest WAL record.
+    open_segs: BinaryHeap<OpenSegEntry>,

    /// Generation number, used to distinguish newly inserted entries in the
    /// binary heap from older entries during checkpoint.
    current_generation: u64,
 }

+///
+/// Per-segment entry in the LayerMap.segs hash map
+///
+/// The last layer that is open for writes is always an InMemoryLayer,
+/// and is kept in a separate field, because there can be only one for
+/// each segment. The older layers, stored on disk, are kept in a
+/// BTreeMap keyed by the layer's start LSN.
+struct SegEntry {
+    pub open: Option<Arc<InMemoryLayer>>,
+    pub historic: BTreeMap<Lsn, Arc<dyn Layer>>,
+}
+
+/// Entry held LayerMap.open_segs, with boilerplate comparison
+/// routines to implement a min-heap ordered by 'oldest_pending_lsn'
+///
+/// Each entry also carries a generation number. It can be used to distinguish
+/// entries with the same 'oldest_pending_lsn'.
+struct OpenSegEntry {
+    pub oldest_pending_lsn: Lsn,
+    pub layer: Arc<InMemoryLayer>,
+    pub generation: u64,
+}
+impl Ord for OpenSegEntry {
+    fn cmp(&self, other: &Self) -> Ordering {
+        // BinaryHeap is a max-heap, and we want a min-heap. Reverse the ordering here
+        // to get that.
+        other.oldest_pending_lsn.cmp(&self.oldest_pending_lsn)
+    }
+}
+impl PartialOrd for OpenSegEntry {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        // BinaryHeap is a max-heap, and we want a min-heap. Reverse the ordering here
+        // to get that. Entries with identical oldest_pending_lsn are ordered by generation
+        Some(
+            other
+                .oldest_pending_lsn
+                .cmp(&self.oldest_pending_lsn)
+                .then_with(|| other.generation.cmp(&self.generation)),
+        )
+    }
+}
+impl PartialEq for OpenSegEntry {
+    fn eq(&self, other: &Self) -> bool {
+        self.oldest_pending_lsn.eq(&other.oldest_pending_lsn)
+    }
+}
+impl Eq for OpenSegEntry {}
+
 impl LayerMap {
    ///
    /// Look up a layer using the given segment tag and LSN. This differs from a
@@ -58,7 +107,23 @@ impl LayerMap {
    pub fn get(&self, tag: &SegmentTag, lsn: Lsn) -> Option<Arc<dyn Layer>> {
        let segentry = self.segs.get(tag)?;

-        segentry.get(lsn)
+        if let Some(open) = &segentry.open {
+            if open.get_start_lsn() <= lsn {
+                let x: Arc<dyn Layer> = Arc::clone(&open) as _;
+                return Some(x);
+            }
+        }
+
+        if let Some((_k, v)) = segentry
+            .historic
+            .range((Included(Lsn(0)), Included(lsn)))
+            .next_back()
+        {
+            let x: Arc<dyn Layer> = Arc::clone(&v) as _;
+            Some(x)
+        } else {
+            None
+        }
    }

    ///
@@ -68,52 +133,50 @@ impl LayerMap {
    pub fn get_open(&self, tag: &SegmentTag) -> Option<Arc<InMemoryLayer>> {
        let segentry = self.segs.get(tag)?;

-        segentry.open.as_ref().map(Arc::clone)
+        if let Some(open) = &segentry.open {
+            Some(Arc::clone(open))
+        } else {
+            None
+        }
    }

    ///
    /// Insert an open in-memory layer
    ///
    pub fn insert_open(&mut self, layer: Arc<InMemoryLayer>) {
-        let segentry = self.segs.entry(layer.get_seg_tag()).or_default();
+        let tag = layer.get_seg_tag();

-        segentry.update_open(Arc::clone(&layer));
+        if let Some(segentry) = self.segs.get_mut(&tag) {
+            if let Some(_old) = &segentry.open {
+                // FIXME: shouldn't exist, but check
+                println!("insert_open() // FIXME: shouldn't exist, but check");
+            }
+            segentry.open = Some(Arc::clone(&layer));
+        } else {
+            let segentry = SegEntry {
+                open: Some(Arc::clone(&layer)),
+                historic: BTreeMap::new(),
+            };
+            self.segs.insert(tag, segentry);
+        }

-        let oldest_pending_lsn = layer.get_oldest_pending_lsn();
-
-        // After a crash and restart, 'oldest_pending_lsn' of the oldest in-memory
-        // layer becomes the WAL streaming starting point, so it better not point
-        // in the middle of a WAL record.
-        assert!(oldest_pending_lsn.is_aligned());
-
-        // Also add it to the binary heap
-        let open_layer_entry = OpenLayerEntry {
+        let opensegentry = OpenSegEntry {
            oldest_pending_lsn: layer.get_oldest_pending_lsn(),
-            layer,
+            layer: layer,
            generation: self.current_generation,
        };
-        self.open_layers.push(open_layer_entry);
+        self.open_segs.push(opensegentry);

        NUM_INMEMORY_LAYERS.inc();
    }

    /// Remove the oldest in-memory layer
    pub fn pop_oldest_open(&mut self) {
-        // Pop it from the binary heap
-        let oldest_entry = self.open_layers.pop().unwrap();
-        let segtag = oldest_entry.layer.get_seg_tag();
+        let opensegentry = self.open_segs.pop().unwrap();
+        let segtag = opensegentry.layer.get_seg_tag();

-        // Also remove it from the SegEntry of this segment
        let mut segentry = self.segs.get_mut(&segtag).unwrap();
-        if Arc::ptr_eq(segentry.open.as_ref().unwrap(), &oldest_entry.layer) {
-            segentry.open = None;
-        } else {
-            // We could have already updated segentry.open for
-            // dropped (non-writeable) layer. This is fine.
-            assert!(!oldest_entry.layer.is_writeable());
-            assert!(oldest_entry.layer.is_dropped());
-        }
-
+        segentry.open = None;
        NUM_INMEMORY_LAYERS.dec();
    }

@@ -121,9 +184,21 @@ impl LayerMap {
    /// Insert an on-disk layer
    ///
    pub fn insert_historic(&mut self, layer: Arc<dyn Layer>) {
-        let segentry = self.segs.entry(layer.get_seg_tag()).or_default();
-        segentry.insert_historic(layer);
+        let tag = layer.get_seg_tag();
+        let start_lsn = layer.get_start_lsn();

+        if let Some(segentry) = self.segs.get_mut(&tag) {
+            segentry.historic.insert(start_lsn, layer);
+        } else {
+            let mut historic = BTreeMap::new();
+            historic.insert(start_lsn, layer);
+
+            let segentry = SegEntry {
+                open: None,
+                historic,
+            };
+            self.segs.insert(tag, segentry);
+        }
        NUM_ONDISK_LAYERS.inc();
    }

@@ -132,39 +207,83 @@ impl LayerMap {
    ///
    /// This should be called when the corresponding file on disk has been deleted.
    ///
-    pub fn remove_historic(&mut self, layer: Arc<dyn Layer>) {
+    pub fn remove_historic(&mut self, layer: &dyn Layer) {
        let tag = layer.get_seg_tag();
+        let start_lsn = layer.get_start_lsn();

        if let Some(segentry) = self.segs.get_mut(&tag) {
-            segentry.historic.remove(&layer);
+            segentry.historic.remove(&start_lsn);
        }
        NUM_ONDISK_LAYERS.dec();
    }

-    // List relations along with a flag that marks if they exist at the given lsn.
-    // spcnode 0 and dbnode 0 have special meanings and mean all tabespaces/databases.
-    // Pass Tag if we're only interested in some relations.
-    pub fn list_relishes(&self, tag: Option<RelTag>, lsn: Lsn) -> Result<HashMap<RelishTag, bool>> {
-        let mut rels: HashMap<RelishTag, bool> = HashMap::new();
+    // List relations that exist at the lsn
+    pub fn list_rels(&self, spcnode: u32, dbnode: u32, lsn: Lsn) -> Result<HashSet<RelTag>> {
+        let mut rels: HashSet<RelTag> = HashSet::new();
+
+        println!("layer list_rels()");

        for (seg, segentry) in self.segs.iter() {
-            match seg.rel {
-                RelishTag::Relation(reltag) => {
-                    if let Some(request_rel) = tag {
-                        if (request_rel.spcnode == 0 || reltag.spcnode == request_rel.spcnode)
-                            && (request_rel.dbnode == 0 || reltag.dbnode == request_rel.dbnode)
+            if let RelishTag::Relation(reltag) = seg.rel {
+                if (spcnode == 0 || reltag.spcnode == spcnode)
+                    && (dbnode == 0 || reltag.dbnode == dbnode)
+                {
+                    // Add only if it exists at the requested LSN.
+                    if let Some(open) = &segentry.open {
+                        println!("explore segentry.open {:?}", open.filename());
+
+                        if open.get_end_lsn() > lsn && open.get_start_lsn() <= lsn {
+                            rels.insert(reltag);
+                            println!("found rel {} at lsn {} in open layer start_lsn {} end lsn {}",
+                             reltag, lsn, open.get_start_lsn(), open.get_end_lsn());
+                            println!("{}", open.dump());
+
+                        }
+                        else
                        {
-                            if let Some(exists) = segentry.exists_at_lsn(lsn)? {
-                                rels.insert(seg.rel, exists);
-                            }
+                            println!("found DROPPED rel {} at lsn {} in open layer start_lsn {} end lsn {}",
+                            reltag, lsn, open.get_start_lsn(), open.get_end_lsn());
+                            println!("{}", open.dump());  
+                        }
+                    } else if let Some((l_start_lsn, layer)) = segentry
+                        .historic
+                        .range((Included(Lsn(0)), Included(lsn)))
+                        .next_back()
+                    {
+                        println!("explore historic segment {:?}", layer.filename());
+
+                        if !layer.is_dropped() && l_start_lsn <= &lsn {
+                            rels.insert(reltag);
+                            println!("found rel {} in historic layer", reltag);
+                            layer.dump()?;
                        }
                    }
                }
-                _ => {
-                    if tag == None {
-                        if let Some(exists) = segentry.exists_at_lsn(lsn)? {
-                            rels.insert(seg.rel, exists);
-                        }
+            }
+        }
+        Ok(rels)
+    }
+
+    // List non-relation relishes that exist at the lsn
+    pub fn list_nonrels(&self, lsn: Lsn) -> Result<HashSet<RelishTag>> {
+        let mut rels: HashSet<RelishTag> = HashSet::new();
+
+        // Scan the timeline directory to get all rels in this timeline.
+        for (seg, segentry) in self.segs.iter() {
+            if let RelishTag::Relation(_) = seg.rel {
+            } else {
+                // Add only if it exists at the requested LSN.
+                if let Some(open) = &segentry.open {
+                    if open.get_end_lsn() > lsn && open.get_start_lsn() <= lsn {
+                        rels.insert(seg.rel);
+                    }
+                } else if let Some((l_start_lsn, layer)) = segentry
+                    .historic
+                    .range((Included(Lsn(0)), Included(lsn)))
+                    .next_back()
+                {
+                    if !layer.is_dropped() && l_start_lsn <= &lsn {
+                        rels.insert(seg.rel);
                    }
                }
            }
@@ -178,31 +297,42 @@ impl LayerMap {
    /// be deleted.
    pub fn newer_image_layer_exists(&self, seg: SegmentTag, lsn: Lsn) -> bool {
        if let Some(segentry) = self.segs.get(&seg) {
-            segentry.newer_image_layer_exists(lsn)
-        } else {
-            false
+            // We only check on-disk layers, because
+            // in-memory layers are not durable
+            for (newer_lsn, layer) in segentry
+                .historic
+                .range((Included(lsn), Included(Lsn(u64::MAX))))
+            {
+                // Ignore layers that depend on an older layer.
+                if layer.is_incremental() {
+                    continue;
+                }
+                if layer.get_end_lsn() > lsn {
+                    trace!(
+                        "found later layer for {}, {} {}-{}",
+                        seg,
+                        lsn,
+                        newer_lsn,
+                        layer.get_end_lsn()
+                    );
+                    return true;
+                } else {
+                    trace!("found singleton layer for {}, {} {}", seg, lsn, newer_lsn);
+                    continue;
+                }
+            }
        }
-    }
-
-    /// Is there any layer for given segment that is alive at the lsn?
-    ///
-    /// This is a public wrapper for SegEntry fucntion,
-    /// used for garbage collection, to determine if some alive layer
-    /// exists at the lsn. If so, we shouldn't delete a newer dropped layer
-    /// to avoid incorrectly making it visible.
-    pub fn layer_exists_at_lsn(&self, seg: SegmentTag, lsn: Lsn) -> Result<bool> {
-        Ok(if let Some(segentry) = self.segs.get(&seg) {
-            segentry.exists_at_lsn(lsn)?.unwrap_or(false)
-        } else {
-            false
-        })
+        trace!("no later layer found for {}, {}", seg, lsn);
+        false
    }

    /// Return the oldest in-memory layer, along with its generation number.
    pub fn peek_oldest_open(&self) -> Option<(Arc<InMemoryLayer>, u64)> {
-        self.open_layers
-            .peek()
-            .map(|oldest_entry| (Arc::clone(&oldest_entry.layer), oldest_entry.generation))
+        if let Some(opensegentry) = self.open_segs.peek() {
+            Some((Arc::clone(&opensegentry.layer), opensegentry.generation))
+        } else {
+            None
+        }
    }

    /// Increment the generation number used to stamp open in-memory layers. Layers
@@ -215,137 +345,25 @@ impl LayerMap {

    pub fn iter_historic_layers(&self) -> HistoricLayerIter {
        HistoricLayerIter {
-            seg_iter: self.segs.iter(),
+            segiter: self.segs.iter(),
            iter: None,
        }
    }
-
-    /// debugging function to print out the contents of the layer map
-    #[allow(unused)]
-    pub fn dump(&self) -> Result<()> {
-        println!("Begin dump LayerMap");
-        for (seg, segentry) in self.segs.iter() {
-            if let Some(open) = &segentry.open {
-                open.dump()?;
-            }
-
-            for layer in segentry.historic.iter() {
-                layer.dump()?;
-            }
-        }
-        println!("End dump LayerMap");
-        Ok(())
-    }
 }

-impl IntervalItem for dyn Layer {
-    type Key = Lsn;
-
-    fn start_key(&self) -> Lsn {
-        self.get_start_lsn()
-    }
-    fn end_key(&self) -> Lsn {
-        self.get_end_lsn()
-    }
-}
-
-///
-/// Per-segment entry in the LayerMap::segs hash map. Holds all the layers
-/// associated with the segment.
-///
-/// The last layer that is open for writes is always an InMemoryLayer,
-/// and is kept in a separate field, because there can be only one for
-/// each segment. The older layers, stored on disk, are kept in an
-/// IntervalTree.
-#[derive(Default)]
-struct SegEntry {
-    open: Option<Arc<InMemoryLayer>>,
-    historic: IntervalTree<dyn Layer>,
-}
-
-impl SegEntry {
-    /// Does the segment exist at given LSN?
-    /// Return None if object is not found in this SegEntry.
-    fn exists_at_lsn(&self, lsn: Lsn) -> Result<Option<bool>> {
-        if let Some(layer) = self.get(lsn) {
-            Ok(Some(layer.get_seg_exists(lsn)?))
-        } else {
-            Ok(None)
+impl Default for LayerMap {
+    fn default() -> Self {
+        LayerMap {
+            segs: HashMap::new(),
+            open_segs: BinaryHeap::new(),
+            current_generation: 0,
        }
    }
-
-    pub fn get(&self, lsn: Lsn) -> Option<Arc<dyn Layer>> {
-        if let Some(open) = &self.open {
-            if open.get_start_lsn() <= lsn {
-                let x: Arc<dyn Layer> = Arc::clone(open) as _;
-                return Some(x);
-            }
-        }
-
-        self.historic.search(lsn)
-    }
-
-    pub fn newer_image_layer_exists(&self, lsn: Lsn) -> bool {
-        // We only check on-disk layers, because
-        // in-memory layers are not durable
-
-        self.historic
-            .iter_newer(lsn)
-            .any(|layer| !layer.is_incremental())
-    }
-
-    // Set new open layer for a SegEntry.
-    // It's ok to rewrite previous open layer,
-    // but only if it is not writeable anymore.
-    pub fn update_open(&mut self, layer: Arc<InMemoryLayer>) {
-        if let Some(prev_open) = &self.open {
-            assert!(!prev_open.is_writeable());
-        }
-        self.open = Some(layer);
-    }
-
-    pub fn insert_historic(&mut self, layer: Arc<dyn Layer>) {
-        self.historic.insert(layer);
-    }
 }

-/// Entry held in LayerMap::open_layers, with boilerplate comparison routines
-/// to implement a min-heap ordered by 'oldest_pending_lsn' and 'generation'
-///
-/// The generation number associated with each entry can be used to distinguish
-/// recently-added entries (i.e after last call to increment_generation()) from older
-/// entries with the same 'oldest_pending_lsn'.
-struct OpenLayerEntry {
-    pub oldest_pending_lsn: Lsn, // copy of layer.get_oldest_pending_lsn()
-    pub generation: u64,
-    pub layer: Arc<InMemoryLayer>,
-}
-impl Ord for OpenLayerEntry {
-    fn cmp(&self, other: &Self) -> Ordering {
-        // BinaryHeap is a max-heap, and we want a min-heap. Reverse the ordering here
-        // to get that. Entries with identical oldest_pending_lsn are ordered by generation
-        other
-            .oldest_pending_lsn
-            .cmp(&self.oldest_pending_lsn)
-            .then_with(|| other.generation.cmp(&self.generation))
-    }
-}
-impl PartialOrd for OpenLayerEntry {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        Some(self.cmp(other))
-    }
-}
-impl PartialEq for OpenLayerEntry {
-    fn eq(&self, other: &Self) -> bool {
-        self.cmp(other) == Ordering::Equal
-    }
-}
-impl Eq for OpenLayerEntry {}
-
-/// Iterator returned by LayerMap::iter_historic_layers()
 pub struct HistoricLayerIter<'a> {
-    seg_iter: std::collections::hash_map::Iter<'a, SegmentTag, SegEntry>,
-    iter: Option<IntervalIter<'a, dyn Layer>>,
+    segiter: std::collections::hash_map::Iter<'a, SegmentTag, SegEntry>,
+    iter: Option<std::collections::btree_map::Iter<'a, Lsn, Arc<dyn Layer>>>,
 }

 impl<'a> Iterator for HistoricLayerIter<'a> {
@@ -355,11 +373,11 @@ impl<'a> Iterator for HistoricLayerIter<'a> {
        loop {
            if let Some(x) = &mut self.iter {
                if let Some(x) = x.next() {
-                    return Some(Arc::clone(&x));
+                    return Some(Arc::clone(&*x.1));
                }
            }
-            if let Some((_tag, segentry)) = self.seg_iter.next() {
-                self.iter = Some(segentry.historic.iter());
+            if let Some(seg) = self.segiter.next() {
+                self.iter = Some(seg.1.historic.iter());
                continue;
            } else {
                return None;
@@ -367,78 +385,3 @@ impl<'a> Iterator for HistoricLayerIter<'a> {
        }
    }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::PageServerConf;
-    use std::str::FromStr;
-    use zenith_utils::zid::{ZTenantId, ZTimelineId};
-
-    /// Arbitrary relation tag, for testing.
-    const TESTREL_A: RelishTag = RelishTag::Relation(RelTag {
-        spcnode: 0,
-        dbnode: 111,
-        relnode: 1000,
-        forknum: 0,
-    });
-
-    /// Construct a dummy InMemoryLayer for testing
-    fn dummy_inmem_layer(
-        conf: &'static PageServerConf,
-        segno: u32,
-        start_lsn: Lsn,
-        oldest_pending_lsn: Lsn,
-    ) -> Arc<InMemoryLayer> {
-        Arc::new(
-            InMemoryLayer::create(
-                conf,
-                ZTimelineId::from_str("00000000000000000000000000000000").unwrap(),
-                ZTenantId::from_str("00000000000000000000000000000000").unwrap(),
-                SegmentTag {
-                    rel: TESTREL_A,
-                    segno,
-                },
-                start_lsn,
-                oldest_pending_lsn,
-            )
-            .unwrap(),
-        )
-    }
-
-    #[test]
-    fn test_open_layers() -> Result<()> {
-        let conf = PageServerConf::dummy_conf(PageServerConf::test_repo_dir("dummy_inmem_layer"));
-        let conf = Box::leak(Box::new(conf));
-
-        let mut layers = LayerMap::default();
-
-        let gen1 = layers.increment_generation();
-        layers.insert_open(dummy_inmem_layer(conf, 0, Lsn(0x100), Lsn(0x100)));
-        layers.insert_open(dummy_inmem_layer(conf, 1, Lsn(0x100), Lsn(0x200)));
-        layers.insert_open(dummy_inmem_layer(conf, 2, Lsn(0x100), Lsn(0x120)));
-        layers.insert_open(dummy_inmem_layer(conf, 3, Lsn(0x100), Lsn(0x110)));
-
-        let gen2 = layers.increment_generation();
-        layers.insert_open(dummy_inmem_layer(conf, 4, Lsn(0x100), Lsn(0x110)));
-        layers.insert_open(dummy_inmem_layer(conf, 5, Lsn(0x100), Lsn(0x100)));
-
-        // A helper function (closure) to pop the next oldest open entry from the layer map,
-        // and assert that it is what we'd expect
-        let mut assert_pop_layer = |expected_segno: u32, expected_generation: u64| {
-            let (l, generation) = layers.peek_oldest_open().unwrap();
-            assert!(l.get_seg_tag().segno == expected_segno);
-            assert!(generation == expected_generation);
-            layers.pop_oldest_open();
-        };
-
-        assert_pop_layer(0, gen1); // 0x100
-        assert_pop_layer(5, gen2); // 0x100
-        assert_pop_layer(3, gen1); // 0x110
-        assert_pop_layer(4, gen2); // 0x110
-        assert_pop_layer(2, gen1); // 0x120
-        assert_pop_layer(1, gen1); // 0x200
-
-        Ok(())
-    }
-}
--- a/pageserver/src/layered_repository/storage_layer.rs
+++ b/pageserver/src/layered_repository/storage_layer.rs
@@ -21,7 +21,7 @@ pub const RELISH_SEG_SIZE: u32 = 10 * 1024 * 1024 / 8192;
 /// Each relish stored in the repository is divided into fixed-sized "segments",
 /// with 10 MB of key-space, or 1280 8k pages each.
 ///
-#[derive(Debug, PartialEq, Eq, PartialOrd, Hash, Ord, Clone, Copy, Serialize, Deserialize)]
+#[derive(Debug, PartialEq, Eq, PartialOrd, Hash, Ord, Clone, Copy)]
 pub struct SegmentTag {
    pub rel: RelishTag,
    pub segno: u32,
@@ -111,23 +111,20 @@ pub trait Layer: Send + Sync {
    /// Identify the relish segment
    fn get_seg_tag(&self) -> SegmentTag;

-    /// Inclusive start bound of the LSN range that this layer holds
+    /// Inclusive start bound of the LSN range that this layer hold
    fn get_start_lsn(&self) -> Lsn;

-    /// Exclusive end bound of the LSN range that this layer holds.
+    /// 'end_lsn' meaning depends on the layer kind:
+    /// - in-memory layer is either unbounded (end_lsn = MAX_LSN) or dropped (end_lsn = drop_lsn)
+    /// - image layer represents snapshot at one LSN, so end_lsn = lsn
+    /// - delta layer has end_lsn
    ///
-    /// - For an open in-memory layer, this is MAX_LSN.
-    /// - For a frozen in-memory layer or a delta layer, this is a valid end bound.
-    /// - An image layer represents snapshot at one LSN, so end_lsn is always the snapshot LSN + 1
+    /// TODO Is end_lsn always exclusive for all layer kinds?
    fn get_end_lsn(&self) -> Lsn;

    /// Is the segment represented by this layer dropped by PostgreSQL?
    fn is_dropped(&self) -> bool;

-    /// Gets the physical location of the layer on disk.
-    /// Some layers, such as in-memory, might not have the location.
-    fn path(&self) -> Option<PathBuf>;
-
    /// Filename used to store this layer on disk. (Even in-memory layers
    /// implement this, to print a handy unique identifier for the layer for
    /// log messages, even though they're never not on disk.)
--- a/pageserver/src/lib.rs
+++ b/pageserver/src/lib.rs
@@ -11,9 +11,9 @@ pub mod basebackup;
 pub mod branches;
 pub mod http;
 pub mod layered_repository;
+pub mod logger;
 pub mod page_service;
 pub mod relish;
-mod relish_storage;
 pub mod repository;
 pub mod restore_local_repo;
 pub mod tenant_mgr;
@@ -21,27 +21,6 @@ pub mod waldecoder;
 pub mod walreceiver;
 pub mod walredo;

-pub mod defaults {
-    use const_format::formatcp;
-    use std::time::Duration;
-
-    pub const DEFAULT_PG_LISTEN_PORT: u16 = 64000;
-    pub const DEFAULT_PG_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_PG_LISTEN_PORT}");
-    pub const DEFAULT_HTTP_LISTEN_PORT: u16 = 9898;
-    pub const DEFAULT_HTTP_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_HTTP_LISTEN_PORT}");
-
-    // FIXME: This current value is very low. I would imagine something like 1 GB or 10 GB
-    // would be more appropriate. But a low value forces the code to be exercised more,
-    // which is good for now to trigger bugs.
-    pub const DEFAULT_CHECKPOINT_DISTANCE: u64 = 256 * 1024 * 1024;
-    pub const DEFAULT_CHECKPOINT_PERIOD: Duration = Duration::from_secs(1);
-
-    pub const DEFAULT_GC_HORIZON: u64 = 64 * 1024 * 1024;
-    pub const DEFAULT_GC_PERIOD: Duration = Duration::from_secs(100);
-
-    pub const DEFAULT_SUPERUSER: &str = "zenith_admin";
-}
-
 lazy_static! {
    static ref LIVE_CONNECTIONS_COUNT: IntGaugeVec = register_int_gauge_vec!(
        "pageserver_live_connections_count",
@@ -51,19 +30,11 @@ lazy_static! {
    .expect("failed to define a metric");
 }

-pub const LOG_FILE_NAME: &str = "pageserver.log";
-
 #[derive(Debug, Clone)]
 pub struct PageServerConf {
    pub daemonize: bool,
-    pub listen_pg_addr: String,
-    pub listen_http_addr: String,
-    // Flush out an inmemory layer, if it's holding WAL older than this
-    // This puts a backstop on how much WAL needs to be re-digested if the
-    // page server crashes.
-    pub checkpoint_distance: u64,
-    pub checkpoint_period: Duration,
-
+    pub listen_addr: String,
+    pub http_endpoint_addr: String,
    pub gc_horizon: u64,
    pub gc_period: Duration,
    pub superuser: String,
@@ -81,7 +52,6 @@ pub struct PageServerConf {
    pub auth_type: AuthType,

    pub auth_validation_public_key_path: Option<PathBuf>,
-    pub relish_storage_config: Option<RelishStorageConfig>,
 }

 impl PageServerConf {
@@ -140,54 +110,4 @@ impl PageServerConf {
    pub fn pg_lib_dir(&self) -> PathBuf {
        self.pg_distrib_dir.join("lib")
    }
-
-    #[cfg(test)]
-    fn test_repo_dir(test_name: &str) -> PathBuf {
-        PathBuf::from(format!("../tmp_check/test_{}", test_name))
-    }
-
-    #[cfg(test)]
-    fn dummy_conf(repo_dir: PathBuf) -> Self {
-        PageServerConf {
-            daemonize: false,
-            checkpoint_distance: defaults::DEFAULT_CHECKPOINT_DISTANCE,
-            checkpoint_period: Duration::from_secs(10),
-            gc_horizon: defaults::DEFAULT_GC_HORIZON,
-            gc_period: Duration::from_secs(10),
-            listen_pg_addr: defaults::DEFAULT_PG_LISTEN_ADDR.to_string(),
-            listen_http_addr: defaults::DEFAULT_HTTP_LISTEN_ADDR.to_string(),
-            superuser: "zenith_admin".to_string(),
-            workdir: repo_dir,
-            pg_distrib_dir: "".into(),
-            auth_type: AuthType::Trust,
-            auth_validation_public_key_path: None,
-            relish_storage_config: None,
-        }
-    }
-}
-
-/// External relish storage configuration, enough for creating a client for that storage.
-#[derive(Debug, Clone)]
-pub enum RelishStorageConfig {
-    /// Root folder to place all stored relish data into.
-    LocalFs(PathBuf),
-    AwsS3(S3Config),
-}
-
-/// AWS S3 bucket coordinates and access credentials to manage the bucket contents (read and write).
-#[derive(Clone)]
-pub struct S3Config {
-    pub bucket_name: String,
-    pub bucket_region: String,
-    pub access_key_id: Option<String>,
-    pub secret_access_key: Option<String>,
-}
-
-impl std::fmt::Debug for S3Config {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("S3Config")
-            .field("bucket_name", &self.bucket_name)
-            .field("bucket_region", &self.bucket_region)
-            .finish()
-    }
 }
--- a/pageserver/src/logger.rs
+++ b/pageserver/src/logger.rs
@@ -0,0 +1,45 @@
+use crate::PageServerConf;
+
+use anyhow::{Context, Result};
+use slog::{Drain, FnValue};
+use std::fs::{File, OpenOptions};
+
+pub fn init_logging(
+    _conf: &PageServerConf,
+    log_filename: &str,
+) -> Result<(slog_scope::GlobalLoggerGuard, File)> {
+    // Don't open the same file for output multiple times;
+    // the different fds could overwrite each other's output.
+    let log_file = OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(&log_filename)
+        .with_context(|| format!("failed to open {:?}", &log_filename))?;
+
+    let logger_file = log_file.try_clone().unwrap();
+
+    let decorator = slog_term::PlainSyncDecorator::new(logger_file);
+    let drain = slog_term::FullFormat::new(decorator).build();
+    let drain = slog::Filter::new(drain, |record: &slog::Record| {
+        if record.level().is_at_least(slog::Level::Info) {
+            return true;
+        }
+        true
+    });
+    let drain = std::sync::Mutex::new(drain).fuse();
+    let logger = slog::Logger::root(
+        drain,
+        slog::o!(
+            "location" =>
+                FnValue(move |record| {
+                    format!("{}, {}:{}",
+                            record.module(),
+                            record.file(),
+                            record.line()
+                    )
+                }
+                )
+        ),
+    );
+    Ok((slog_scope::set_global_logger(logger), log_file))
+}
--- a/pageserver/src/page_service.rs
+++ b/pageserver/src/page_service.rs
@@ -10,7 +10,7 @@
 //     *callmemaybe <zenith timelineid> $url* -- ask pageserver to start walreceiver on $url
 //

-use anyhow::{anyhow, bail, ensure, Result};
+use anyhow::{anyhow, bail, ensure, Context, Result};
 use bytes::{Buf, BufMut, Bytes, BytesMut};
 use lazy_static::lazy_static;
 use log::*;
@@ -35,110 +35,72 @@ use zenith_utils::zid::{ZTenantId, ZTimelineId};
 use crate::basebackup;
 use crate::branches;
 use crate::relish::*;
-use crate::repository::Timeline;
 use crate::tenant_mgr;
 use crate::walreceiver;
 use crate::PageServerConf;

 // Wrapped in libpq CopyData
 enum PagestreamFeMessage {
-    Exists(PagestreamExistsRequest),
-    Nblocks(PagestreamNblocksRequest),
-    GetPage(PagestreamGetPageRequest),
+    Exists(PagestreamRequest),
+    Nblocks(PagestreamRequest),
+    Read(PagestreamRequest),
 }

 // Wrapped in libpq CopyData
 enum PagestreamBeMessage {
-    Exists(PagestreamExistsResponse),
-    Nblocks(PagestreamNblocksResponse),
-    GetPage(PagestreamGetPageResponse),
-    Error(PagestreamErrorResponse),
+    Status(PagestreamStatusResponse),
+    Nblocks(PagestreamStatusResponse),
+    Read(PagestreamReadResponse),
 }

 #[derive(Debug)]
-struct PagestreamExistsRequest {
-    latest: bool,
-    lsn: Lsn,
-    rel: RelTag,
-}
-
-#[derive(Debug)]
-struct PagestreamNblocksRequest {
-    latest: bool,
-    lsn: Lsn,
-    rel: RelTag,
-}
-
-#[derive(Debug)]
-struct PagestreamGetPageRequest {
-    latest: bool,
-    lsn: Lsn,
-    rel: RelTag,
+struct PagestreamRequest {
+    spcnode: u32,
+    dbnode: u32,
+    relnode: u32,
+    forknum: u8,
    blkno: u32,
+    lsn: Lsn,
 }

 #[derive(Debug)]
-struct PagestreamExistsResponse {
-    exists: bool,
-}
-
-#[derive(Debug)]
-struct PagestreamNblocksResponse {
+struct PagestreamStatusResponse {
+    ok: bool,
    n_blocks: u32,
 }

 #[derive(Debug)]
-struct PagestreamGetPageResponse {
+struct PagestreamReadResponse {
+    ok: bool,
+    n_blocks: u32,
    page: Bytes,
 }

-#[derive(Debug)]
-struct PagestreamErrorResponse {
-    message: String,
-}
-
 impl PagestreamFeMessage {
    fn parse(mut body: Bytes) -> anyhow::Result<PagestreamFeMessage> {
        // TODO these gets can fail

-        // these correspond to the ZenithMessageTag enum in pagestore_client.h
-        //
+        let smgr_tag = body.get_u8();
+        let zreq = PagestreamRequest {
+            spcnode: body.get_u32(),
+            dbnode: body.get_u32(),
+            relnode: body.get_u32(),
+            forknum: body.get_u8(),
+            blkno: body.get_u32(),
+            lsn: Lsn::from(body.get_u64()),
+        };
+
        // TODO: consider using protobuf or serde bincode for less error prone
        // serialization.
-        let msg_tag = body.get_u8();
-        match msg_tag {
-            0 => Ok(PagestreamFeMessage::Exists(PagestreamExistsRequest {
-                latest: body.get_u8() != 0,
-                lsn: Lsn::from(body.get_u64()),
-                rel: RelTag {
-                    spcnode: body.get_u32(),
-                    dbnode: body.get_u32(),
-                    relnode: body.get_u32(),
-                    forknum: body.get_u8(),
-                },
-            })),
-            1 => Ok(PagestreamFeMessage::Nblocks(PagestreamNblocksRequest {
-                latest: body.get_u8() != 0,
-                lsn: Lsn::from(body.get_u64()),
-                rel: RelTag {
-                    spcnode: body.get_u32(),
-                    dbnode: body.get_u32(),
-                    relnode: body.get_u32(),
-                    forknum: body.get_u8(),
-                },
-            })),
-            2 => Ok(PagestreamFeMessage::GetPage(PagestreamGetPageRequest {
-                latest: body.get_u8() != 0,
-                lsn: Lsn::from(body.get_u64()),
-                rel: RelTag {
-                    spcnode: body.get_u32(),
-                    dbnode: body.get_u32(),
-                    relnode: body.get_u32(),
-                    forknum: body.get_u8(),
-                },
-                blkno: body.get_u32(),
-            })),
-            _ => bail!("unknown smgr message tag: {},'{:?}'", msg_tag, body),
+        match smgr_tag {
+            0 => Ok(PagestreamFeMessage::Exists(zreq)),
+            1 => Ok(PagestreamFeMessage::Nblocks(zreq)),
+            2 => Ok(PagestreamFeMessage::Read(zreq)),
+            _ => Err(anyhow!(
+                "unknown smgr message tag: {},'{:?}'",
+                smgr_tag,
+                body
+            )),
        }
    }
 }
@@ -148,26 +110,24 @@ impl PagestreamBeMessage {
        let mut bytes = BytesMut::new();

        match self {
-            Self::Exists(resp) => {
+            Self::Status(resp) => {
                bytes.put_u8(100); /* tag from pagestore_client.h */
-                bytes.put_u8(resp.exists as u8);
+                bytes.put_u8(resp.ok as u8);
+                bytes.put_u32(resp.n_blocks);
            }

            Self::Nblocks(resp) => {
                bytes.put_u8(101); /* tag from pagestore_client.h */
+                bytes.put_u8(resp.ok as u8);
                bytes.put_u32(resp.n_blocks);
            }

-            Self::GetPage(resp) => {
+            Self::Read(resp) => {
                bytes.put_u8(102); /* tag from pagestore_client.h */
+                bytes.put_u8(resp.ok as u8);
+                bytes.put_u32(resp.n_blocks);
                bytes.put(&resp.page[..]);
            }
-
-            Self::Error(resp) => {
-                bytes.put_u8(103); /* tag from pagestore_client.h */
-                bytes.put(resp.message.as_bytes());
-                bytes.put_u8(0); // null terminator
-            }
        }

        bytes.into()
@@ -254,6 +214,14 @@ impl PageServerHandler {
        }
    }

+    fn handle_controlfile(&self, pgb: &mut PostgresBackend) -> io::Result<()> {
+        pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
+            .write_message_noflush(&BeMessage::ControlFile)?
+            .write_message(&BeMessage::CommandComplete(b"SELECT 1"))?;
+
+        Ok(())
+    }
+
    fn handle_pagerequests(
        &self,
        pgb: &mut PostgresBackend,
@@ -261,7 +229,10 @@ impl PageServerHandler {
        tenantid: ZTenantId,
    ) -> anyhow::Result<()> {
        // Check that the timeline exists
-        let timeline = tenant_mgr::get_timeline_for_tenant(tenantid, timelineid)?;
+        let repository = tenant_mgr::get_repository_for_tenant(&tenantid)?;
+        let timeline = repository
+            .get_timeline(timelineid)
+            .context(format!("error fetching timeline {}", timelineid))?;

        /* switch client to COPYBOTH */
        pgb.write_message(&BeMessage::CopyBothResponse)?;
@@ -277,29 +248,81 @@ impl PageServerHandler {
            let zenith_fe_msg = PagestreamFeMessage::parse(copy_data_bytes)?;

            let response = match zenith_fe_msg {
-                PagestreamFeMessage::Exists(req) => SMGR_QUERY_TIME
-                    .with_label_values(&["get_rel_exists"])
-                    .observe_closure_duration(|| {
-                        self.handle_get_rel_exists_request(&*timeline, &req)
-                    }),
-                PagestreamFeMessage::Nblocks(req) => SMGR_QUERY_TIME
-                    .with_label_values(&["get_rel_size"])
-                    .observe_closure_duration(|| self.handle_get_nblocks_request(&*timeline, &req)),
-                PagestreamFeMessage::GetPage(req) => SMGR_QUERY_TIME
-                    .with_label_values(&["get_page_at_lsn"])
-                    .observe_closure_duration(|| {
-                        self.handle_get_page_at_lsn_request(&*timeline, &req)
-                    }),
-            };
+                PagestreamFeMessage::Exists(req) => {
+                    let rel = RelTag {
+                        spcnode: req.spcnode,
+                        dbnode: req.dbnode,
+                        relnode: req.relnode,
+                        forknum: req.forknum,
+                    };
+                    let tag = RelishTag::Relation(rel);

-            let response = response.unwrap_or_else(|e| {
-                // print the all details to the log with {:#}, but for the client the
-                // error message is enough
-                error!("error reading relation or page version: {:#}", e);
-                PagestreamBeMessage::Error(PagestreamErrorResponse {
-                    message: e.to_string(),
-                })
-            });
+                    let exist = SMGR_QUERY_TIME
+                        .with_label_values(&["get_rel_exists"])
+                        .observe_closure_duration(|| {
+                            timeline.get_rel_exists(tag, req.lsn).unwrap_or(false)
+                        });
+
+                    PagestreamBeMessage::Status(PagestreamStatusResponse {
+                        ok: exist,
+                        n_blocks: 0,
+                    })
+                }
+                PagestreamFeMessage::Nblocks(req) => {
+                    let rel = RelTag {
+                        spcnode: req.spcnode,
+                        dbnode: req.dbnode,
+                        relnode: req.relnode,
+                        forknum: req.forknum,
+                    };
+                    let tag = RelishTag::Relation(rel);
+
+                    let n_blocks = SMGR_QUERY_TIME
+                        .with_label_values(&["get_rel_size"])
+                        .observe_closure_duration(|| {
+                            // Return 0 if relation is not found.
+                            // This is what postgres smgr expects.
+                            timeline
+                                .get_relish_size(tag, req.lsn)
+                                .unwrap_or(Some(0))
+                                .unwrap_or(0)
+                        });
+
+                    PagestreamBeMessage::Nblocks(PagestreamStatusResponse { ok: true, n_blocks })
+                }
+                PagestreamFeMessage::Read(req) => {
+                    let rel = RelTag {
+                        spcnode: req.spcnode,
+                        dbnode: req.dbnode,
+                        relnode: req.relnode,
+                        forknum: req.forknum,
+                    };
+                    let tag = RelishTag::Relation(rel);
+
+                    let read_response = SMGR_QUERY_TIME
+                        .with_label_values(&["get_page_at_lsn"])
+                        .observe_closure_duration(|| {
+                            match timeline.get_page_at_lsn(tag, req.blkno, req.lsn) {
+                                Ok(p) => PagestreamReadResponse {
+                                    ok: true,
+                                    n_blocks: 0,
+                                    page: p,
+                                },
+                                Err(e) => {
+                                    const ZERO_PAGE: [u8; 8192] = [0; 8192];
+                                    error!("get_page_at_lsn: {}", e);
+                                    PagestreamReadResponse {
+                                        ok: false,
+                                        n_blocks: 0,
+                                        page: Bytes::from_static(&ZERO_PAGE),
+                                    }
+                                }
+                            }
+                        });
+
+                    PagestreamBeMessage::Read(read_response)
+                }
+            };

            pgb.write_message(&BeMessage::CopyData(&response.serialize()))?;
        }
@@ -307,106 +330,6 @@ impl PageServerHandler {
        Ok(())
    }

-    /// Helper function to handle the LSN from client request.
-    ///
-    /// Each GetPage (and Exists and Nblocks) request includes information about
-    /// which version of the page is being requested. The client can request the
-    /// latest version of the page, or the version that's valid at a particular
-    /// LSN. The primary compute node will always request the latest page
-    /// version, while a standby will request a version at the LSN that it's
-    /// currently caught up to.
-    ///
-    /// In either case, if the page server hasn't received the WAL up to the
-    /// requested LSN yet, we will wait for it to arrive. The return value is
-    /// the LSN that should be used to look up the page versions.
-    fn wait_or_get_last_lsn(timeline: &dyn Timeline, lsn: Lsn, latest: bool) -> Result<Lsn> {
-        if latest {
-            // Latest page version was requested. If LSN is given, it is a hint
-            // to the page server that there have been no modifications to the
-            // page after that LSN. If we haven't received WAL up to that point,
-            // wait until it arrives.
-            let last_record_lsn = timeline.get_last_record_lsn();
-
-            // Note: this covers the special case that lsn == Lsn(0). That
-            // special case means "return the latest version whatever it is",
-            // and it's used for bootstrapping purposes, when the page server is
-            // connected directly to the compute node. That is needed because
-            // when you connect to the compute node, to receive the WAL, the
-            // walsender process will do a look up in the pg_authid catalog
-            // table for authentication. That poses a deadlock problem: the
-            // catalog table lookup will send a GetPage request, but the GetPage
-            // request will block in the page server because the recent WAL
-            // hasn't been received yet, and it cannot be received until the
-            // walsender completes the authentication and starts streaming the
-            // WAL.
-            if lsn <= last_record_lsn {
-                Ok(last_record_lsn)
-            } else {
-                timeline.wait_lsn(lsn)?;
-                // Since we waited for 'lsn' to arrive, that is now the last
-                // record LSN. (Or close enough for our purposes; the
-                // last-record LSN can advance immediately after we return
-                // anyway)
-                Ok(lsn)
-            }
-        } else {
-            if lsn == Lsn(0) {
-                bail!("invalid LSN(0) in request");
-            }
-            timeline.wait_lsn(lsn)?;
-            Ok(lsn)
-        }
-    }
-
-    fn handle_get_rel_exists_request(
-        &self,
-        timeline: &dyn Timeline,
-        req: &PagestreamExistsRequest,
-    ) -> Result<PagestreamBeMessage> {
-        let tag = RelishTag::Relation(req.rel);
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest)?;
-
-        let exists = timeline.get_rel_exists(tag, lsn)?;
-
-        Ok(PagestreamBeMessage::Exists(PagestreamExistsResponse {
-            exists,
-        }))
-    }
-
-    fn handle_get_nblocks_request(
-        &self,
-        timeline: &dyn Timeline,
-        req: &PagestreamNblocksRequest,
-    ) -> Result<PagestreamBeMessage> {
-        let tag = RelishTag::Relation(req.rel);
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest)?;
-
-        let n_blocks = timeline.get_relish_size(tag, lsn)?;
-
-        // Return 0 if relation is not found.
-        // This is what postgres smgr expects.
-        let n_blocks = n_blocks.unwrap_or(0);
-
-        Ok(PagestreamBeMessage::Nblocks(PagestreamNblocksResponse {
-            n_blocks,
-        }))
-    }
-
-    fn handle_get_page_at_lsn_request(
-        &self,
-        timeline: &dyn Timeline,
-        req: &PagestreamGetPageRequest,
-    ) -> Result<PagestreamBeMessage> {
-        let tag = RelishTag::Relation(req.rel);
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest)?;
-
-        let page = timeline.get_page_at_lsn(tag, req.blkno, lsn)?;
-
-        Ok(PagestreamBeMessage::GetPage(PagestreamGetPageResponse {
-            page,
-        }))
-    }
-
    fn handle_basebackup_request(
        &self,
        pgb: &mut PostgresBackend,
@@ -415,8 +338,10 @@ impl PageServerHandler {
        tenantid: ZTenantId,
    ) -> anyhow::Result<()> {
        // check that the timeline exists
-        let timeline = tenant_mgr::get_timeline_for_tenant(tenantid, timelineid)?;
-
+        let repository = tenant_mgr::get_repository_for_tenant(&tenantid)?;
+        let timeline = repository
+            .get_timeline(timelineid)
+            .context(format!("error fetching timeline {}", timelineid))?;
        /* switch client to COPYOUT */
        pgb.write_message(&BeMessage::CopyOutResponse)?;
        info!("sent CopyOut");
@@ -424,7 +349,7 @@ impl PageServerHandler {
        /* Send a tarball of the latest layer on the timeline */
        {
            let mut writer = CopyDataSink { pgb };
-            let mut basebackup = basebackup::Basebackup::new(&mut writer, &timeline, lsn)?;
+            let mut basebackup = basebackup::Basebackup::new(&mut writer, &timeline, lsn);
            basebackup.send_tarball()?;
        }
        pgb.write_message(&BeMessage::CopyDone)?;
@@ -447,7 +372,7 @@ impl PageServerHandler {
            .claims
            .as_ref()
            .expect("claims presence already checked");
-        auth::check_permission(claims, tenantid)
+        Ok(auth::check_permission(claims, tenantid)?)
    }
 }

@@ -464,7 +389,7 @@ impl postgres_backend::Handler for PageServerHandler {
            .as_ref()
            .as_ref()
            .unwrap()
-            .decode(str::from_utf8(jwt_response)?)?;
+            .decode(&str::from_utf8(jwt_response)?)?;

        if matches!(data.claims.scope, Scope::Tenant) {
            ensure!(
@@ -496,9 +421,11 @@ impl postgres_backend::Handler for PageServerHandler {
        }
        let query_string = std::str::from_utf8(&query_string)?;

-        if query_string.starts_with("pagestream ") {
+        if query_string.starts_with("controlfile") {
+            self.handle_controlfile(pgb)?;
+        } else if query_string.starts_with("pagestream ") {
            let (_, params_raw) = query_string.split_at("pagestream ".len());
-            let params = params_raw.split(' ').collect::<Vec<_>>();
+            let params = params_raw.split(" ").collect::<Vec<_>>();
            ensure!(
                params.len() == 2,
                "invalid param number for pagestream command"
@@ -552,9 +479,12 @@ impl postgres_backend::Handler for PageServerHandler {
            self.check_permission(Some(tenantid))?;

            // Check that the timeline exists
-            tenant_mgr::get_timeline_for_tenant(tenantid, timelineid)?;
+            let repository = tenant_mgr::get_repository_for_tenant(&tenantid)?;
+            repository
+                .get_timeline(timelineid)
+                .context(format!("error fetching timeline {}", timelineid))?;

-            walreceiver::launch_wal_receiver(self.conf, timelineid, &connstr, tenantid.to_owned());
+            walreceiver::launch_wal_receiver(&self.conf, timelineid, &connstr, tenantid.to_owned());

            pgb.write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
        } else if query_string.starts_with("branch_create ") {
@@ -562,10 +492,10 @@ impl postgres_backend::Handler for PageServerHandler {

            // branch_create <tenantid> <branchname> <startpoint>
            // TODO lazy static
-            // TODO: escaping, to allow branch names with spaces
+            // TOOD: escaping, to allow branch names with spaces
            let re = Regex::new(r"^branch_create ([[:xdigit:]]+) (\S+) ([^\r\n\s;]+)[\r\n\s;]*;?$")
                .unwrap();
-            let caps = re.captures(query_string).ok_or_else(err)?;
+            let caps = re.captures(&query_string).ok_or_else(err)?;

            let tenantid = ZTenantId::from_str(caps.get(1).unwrap().as_str())?;
            let branchname = caps.get(2).ok_or_else(err)?.as_str().to_owned();
@@ -574,7 +504,7 @@ impl postgres_backend::Handler for PageServerHandler {
            self.check_permission(Some(tenantid))?;

            let branch =
-                branches::create_branch(self.conf, &branchname, &startpoint_str, &tenantid)?;
+                branches::create_branch(&self.conf, &branchname, &startpoint_str, &tenantid)?;
            let branch = serde_json::to_vec(&branch)?;

            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
@@ -589,14 +519,14 @@ impl postgres_backend::Handler for PageServerHandler {

            let tenantid = ZTenantId::from_str(caps.get(1).unwrap().as_str())?;

-            let branches = crate::branches::get_branches(self.conf, &tenantid)?;
+            let branches = crate::branches::get_branches(&self.conf, &tenantid)?;
            let branches_buf = serde_json::to_vec(&branches)?;

            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
                .write_message_noflush(&BeMessage::DataRow(&[Some(&branches_buf)]))?
                .write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
        } else if query_string.starts_with("tenant_list") {
-            let tenants = crate::branches::get_tenants(self.conf)?;
+            let tenants = crate::branches::get_tenants(&self.conf)?;
            let tenants_buf = serde_json::to_vec(&tenants)?;

            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
@@ -607,13 +537,13 @@ impl postgres_backend::Handler for PageServerHandler {

            // tenant_create <tenantid>
            let re = Regex::new(r"^tenant_create ([[:xdigit:]]+)$").unwrap();
-            let caps = re.captures(query_string).ok_or_else(err)?;
+            let caps = re.captures(&query_string).ok_or_else(err)?;

            self.check_permission(None)?;

            let tenantid = ZTenantId::from_str(caps.get(1).unwrap().as_str())?;

-            tenant_mgr::create_repository_for_tenant(self.conf, tenantid)?;
+            tenant_mgr::create_repository_for_tenant(&self.conf, tenantid)?;

            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
                .write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
@@ -647,7 +577,7 @@ impl postgres_backend::Handler for PageServerHandler {
                .map(|h| h.as_str().parse())
                .unwrap_or(Ok(self.conf.gc_horizon))?;

-            let repo = tenant_mgr::get_repository_for_tenant(tenantid)?;
+            let repo = tenant_mgr::get_repository_for_tenant(&tenantid)?;

            let result = repo.gc_iteration(Some(timelineid), gc_horizon, true)?;

@@ -656,64 +586,50 @@ impl postgres_backend::Handler for PageServerHandler {
                RowDescriptor::int8_col(b"layer_relfiles_needed_by_cutoff"),
                RowDescriptor::int8_col(b"layer_relfiles_needed_by_branches"),
                RowDescriptor::int8_col(b"layer_relfiles_not_updated"),
-                RowDescriptor::int8_col(b"layer_relfiles_needed_as_tombstone"),
                RowDescriptor::int8_col(b"layer_relfiles_removed"),
                RowDescriptor::int8_col(b"layer_relfiles_dropped"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_total"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_needed_by_cutoff"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_needed_by_branches"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_not_updated"),
-                RowDescriptor::int8_col(b"layer_nonrelfiles_needed_as_tombstone"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_removed"),
                RowDescriptor::int8_col(b"layer_nonrelfiles_dropped"),
                RowDescriptor::int8_col(b"elapsed"),
            ]))?
            .write_message_noflush(&BeMessage::DataRow(&[
-                Some(result.ondisk_relfiles_total.to_string().as_bytes()),
+                Some(&result.ondisk_relfiles_total.to_string().as_bytes()),
                Some(
-                    result
+                    &result
                        .ondisk_relfiles_needed_by_cutoff
                        .to_string()
                        .as_bytes(),
                ),
                Some(
-                    result
+                    &result
                        .ondisk_relfiles_needed_by_branches
                        .to_string()
                        .as_bytes(),
                ),
-                Some(result.ondisk_relfiles_not_updated.to_string().as_bytes()),
+                Some(&result.ondisk_relfiles_not_updated.to_string().as_bytes()),
+                Some(&result.ondisk_relfiles_removed.to_string().as_bytes()),
+                Some(&result.ondisk_relfiles_dropped.to_string().as_bytes()),
+                Some(&result.ondisk_nonrelfiles_total.to_string().as_bytes()),
                Some(
-                    result
-                        .ondisk_relfiles_needed_as_tombstone
-                        .to_string()
-                        .as_bytes(),
-                ),
-                Some(result.ondisk_relfiles_removed.to_string().as_bytes()),
-                Some(result.ondisk_relfiles_dropped.to_string().as_bytes()),
-                Some(result.ondisk_nonrelfiles_total.to_string().as_bytes()),
-                Some(
-                    result
+                    &result
                        .ondisk_nonrelfiles_needed_by_cutoff
                        .to_string()
                        .as_bytes(),
                ),
                Some(
-                    result
+                    &result
                        .ondisk_nonrelfiles_needed_by_branches
                        .to_string()
                        .as_bytes(),
                ),
-                Some(result.ondisk_nonrelfiles_not_updated.to_string().as_bytes()),
-                Some(
-                    result
-                        .ondisk_nonrelfiles_needed_as_tombstone
-                        .to_string()
-                        .as_bytes(),
-                ),
-                Some(result.ondisk_nonrelfiles_removed.to_string().as_bytes()),
-                Some(result.ondisk_nonrelfiles_dropped.to_string().as_bytes()),
-                Some(result.elapsed.as_millis().to_string().as_bytes()),
+                Some(&result.ondisk_nonrelfiles_not_updated.to_string().as_bytes()),
+                Some(&result.ondisk_nonrelfiles_removed.to_string().as_bytes()),
+                Some(&result.ondisk_nonrelfiles_dropped.to_string().as_bytes()),
+                Some(&result.elapsed.as_millis().to_string().as_bytes()),
            ]))?
            .write_message(&BeMessage::CommandComplete(b"SELECT 1"))?;
        } else {
--- a/pageserver/src/relish.rs
+++ b/pageserver/src/relish.rs
@@ -125,7 +125,11 @@ impl RelishTag {

    // convenience function to check if this relish is a normal relation.
    pub const fn is_relation(&self) -> bool {
-        matches!(self, RelishTag::Relation(_))
+        if let RelishTag::Relation(_) = self {
+            true
+        } else {
+            false
+        }
    }
 }

--- a/pageserver/src/relish_storage.rs
+++ b/pageserver/src/relish_storage.rs
@@ -1,54 +0,0 @@
-//! Abstractions for the page server to store its relish layer data in the external storage.
-//!
-//! Main purpose of this module subtree is to provide a set of abstractions to manage the storage state
-//! in a way, optimal for page server.
-//!
-//! The abstractions hide multiple custom external storage API implementations,
-//! such as AWS S3, local filesystem, etc., located in the submodules.
-
-mod local_fs;
-mod rust_s3;
-/// A queue and the background machinery behind it to upload
-/// local page server layer files to external storage.
-pub mod storage_uploader;
-
-use std::path::Path;
-
-use anyhow::Context;
-
-/// Storage (potentially remote) API to manage its state.
-#[async_trait::async_trait]
-pub trait RelishStorage: Send + Sync {
-    type RelishStoragePath;
-
-    fn derive_destination(
-        page_server_workdir: &Path,
-        relish_local_path: &Path,
-    ) -> anyhow::Result<Self::RelishStoragePath>;
-
-    async fn list_relishes(&self) -> anyhow::Result<Vec<Self::RelishStoragePath>>;
-
-    async fn download_relish(
-        &self,
-        from: &Self::RelishStoragePath,
-        to: &Path,
-    ) -> anyhow::Result<()>;
-
-    async fn delete_relish(&self, path: &Self::RelishStoragePath) -> anyhow::Result<()>;
-
-    async fn upload_relish(&self, from: &Path, to: &Self::RelishStoragePath) -> anyhow::Result<()>;
-}
-
-fn strip_workspace_prefix<'a>(
-    page_server_workdir: &'a Path,
-    relish_local_path: &'a Path,
-) -> anyhow::Result<&'a Path> {
-    relish_local_path
-        .strip_prefix(page_server_workdir)
-        .with_context(|| {
-            format!(
-                "Unexpected: relish local path '{}' is not relevant to server workdir",
-                relish_local_path.display(),
-            )
-        })
-}
--- a/pageserver/src/relish_storage/local_fs.rs
+++ b/pageserver/src/relish_storage/local_fs.rs
@@ -1,158 +0,0 @@
-//! Local filesystem relish storage.
-//!
-//! Page server already stores layer data on the server, when freezing it.
-//! This storage serves a way to
-//!
-//! * test things locally simply
-//! * allow to compabre both binary sets
-//! * help validating the relish storage API
-
-use std::{
-    future::Future,
-    path::{Path, PathBuf},
-    pin::Pin,
-};
-
-use anyhow::{bail, Context};
-
-use super::{strip_workspace_prefix, RelishStorage};
-
-pub struct LocalFs {
-    root: PathBuf,
-}
-
-impl LocalFs {
-    /// Atetmpts to create local FS relish storage, also creates the directory provided, if not exists.
-    pub fn new(root: PathBuf) -> anyhow::Result<Self> {
-        if !root.exists() {
-            std::fs::create_dir_all(&root).with_context(|| {
-                format!(
-                    "Failed to create all directories in the given root path {}",
-                    root.display(),
-                )
-            })?;
-        }
-        Ok(Self { root })
-    }
-
-    fn resolve_in_storage(&self, path: &Path) -> anyhow::Result<PathBuf> {
-        if path.is_relative() {
-            Ok(self.root.join(path))
-        } else if path.starts_with(&self.root) {
-            Ok(path.to_path_buf())
-        } else {
-            bail!(
-                "Path '{}' does not belong to the current storage",
-                path.display()
-            )
-        }
-    }
-}
-
-#[async_trait::async_trait]
-impl RelishStorage for LocalFs {
-    type RelishStoragePath = PathBuf;
-
-    fn derive_destination(
-        page_server_workdir: &Path,
-        relish_local_path: &Path,
-    ) -> anyhow::Result<Self::RelishStoragePath> {
-        Ok(strip_workspace_prefix(page_server_workdir, relish_local_path)?.to_path_buf())
-    }
-
-    async fn list_relishes(&self) -> anyhow::Result<Vec<Self::RelishStoragePath>> {
-        Ok(get_all_files(&self.root).await?.into_iter().collect())
-    }
-
-    async fn download_relish(
-        &self,
-        from: &Self::RelishStoragePath,
-        to: &Path,
-    ) -> anyhow::Result<()> {
-        let file_path = self.resolve_in_storage(from)?;
-        if file_path.exists() && file_path.is_file() {
-            create_target_directory(to).await?;
-            tokio::fs::copy(file_path, to).await?;
-            Ok(())
-        } else {
-            bail!(
-                "File '{}' either does not exist or is not a file",
-                file_path.display()
-            )
-        }
-    }
-
-    async fn delete_relish(&self, path: &Self::RelishStoragePath) -> anyhow::Result<()> {
-        let file_path = self.resolve_in_storage(path)?;
-        if file_path.exists() && file_path.is_file() {
-            Ok(tokio::fs::remove_file(file_path).await?)
-        } else {
-            bail!(
-                "File '{}' either does not exist or is not a file",
-                file_path.display()
-            )
-        }
-    }
-
-    async fn upload_relish(&self, from: &Path, to: &Self::RelishStoragePath) -> anyhow::Result<()> {
-        let target_file_path = self.resolve_in_storage(to)?;
-        create_target_directory(&target_file_path).await?;
-
-        tokio::fs::copy(&from, &target_file_path)
-            .await
-            .with_context(|| {
-                format!(
-                    "Failed to upload relish '{}' to local storage",
-                    from.display(),
-                )
-            })?;
-        Ok(())
-    }
-}
-
-fn get_all_files<'a, P>(
-    directory_path: P,
-) -> Pin<Box<dyn Future<Output = anyhow::Result<Vec<PathBuf>>> + Send + Sync + 'a>>
-where
-    P: AsRef<Path> + Send + Sync + 'a,
-{
-    Box::pin(async move {
-        let directory_path = directory_path.as_ref();
-        if directory_path.exists() {
-            if directory_path.is_dir() {
-                let mut paths = Vec::new();
-                let mut dir_contents = tokio::fs::read_dir(directory_path).await?;
-                while let Some(dir_entry) = dir_contents.next_entry().await? {
-                    let file_type = dir_entry.file_type().await?;
-                    let entry_path = dir_entry.path();
-                    if file_type.is_symlink() {
-                        log::debug!("{:?} us a symlink, skipping", entry_path)
-                    } else if file_type.is_dir() {
-                        paths.extend(get_all_files(entry_path).await?.into_iter())
-                    } else {
-                        paths.push(dir_entry.path());
-                    }
-                }
-                Ok(paths)
-            } else {
-                bail!("Path '{}' is not a directory", directory_path.display())
-            }
-        } else {
-            Ok(Vec::new())
-        }
-    })
-}
-
-async fn create_target_directory(target_file_path: &Path) -> anyhow::Result<()> {
-    let target_dir = match target_file_path.parent() {
-        Some(parent_dir) => parent_dir,
-        None => bail!(
-            "Relish path '{}' has no parent directory",
-            target_file_path.display()
-        ),
-    };
-    if !target_dir.exists() {
-        tokio::fs::create_dir_all(target_dir).await?;
-    }
-    Ok(())
-}
--- a/pageserver/src/relish_storage/rust_s3.rs
+++ b/pageserver/src/relish_storage/rust_s3.rs
@@ -1,144 +0,0 @@
-//! A wrapper around AWS S3 client library `rust_s3` to be used a relish storage.
-
-use std::path::Path;
-
-use anyhow::Context;
-use s3::{bucket::Bucket, creds::Credentials, region::Region};
-
-use crate::{relish_storage::strip_workspace_prefix, S3Config};
-
-use super::RelishStorage;
-
-const S3_FILE_SEPARATOR: char = '/';
-
-#[derive(Debug)]
-pub struct S3ObjectKey(String);
-
-impl S3ObjectKey {
-    fn key(&self) -> &str {
-        &self.0
-    }
-}
-
-/// AWS S3 relish storage.
-pub struct RustS3 {
-    bucket: Bucket,
-}
-
-impl RustS3 {
-    /// Creates the relish storage, errors if incorrect AWS S3 configuration provided.
-    pub fn new(aws_config: &S3Config) -> anyhow::Result<Self> {
-        let region = aws_config
-            .bucket_region
-            .parse::<Region>()
-            .context("Failed to parse the s3 region from config")?;
-        let credentials = Credentials::new(
-            aws_config.access_key_id.as_deref(),
-            aws_config.secret_access_key.as_deref(),
-            None,
-            None,
-            None,
-        )
-        .context("Failed to create the s3 credentials")?;
-        Ok(Self {
-            bucket: Bucket::new_with_path_style(
-                aws_config.bucket_name.as_str(),
-                region,
-                credentials,
-            )
-            .context("Failed to create the s3 bucket")?,
-        })
-    }
-}
-
-#[async_trait::async_trait]
-impl RelishStorage for RustS3 {
-    type RelishStoragePath = S3ObjectKey;
-
-    fn derive_destination(
-        page_server_workdir: &Path,
-        relish_local_path: &Path,
-    ) -> anyhow::Result<Self::RelishStoragePath> {
-        let relative_path = strip_workspace_prefix(page_server_workdir, relish_local_path)?;
-        let mut key = String::new();
-        for segment in relative_path {
-            key.push(S3_FILE_SEPARATOR);
-            key.push_str(&segment.to_string_lossy());
-        }
-        Ok(S3ObjectKey(key))
-    }
-
-    async fn list_relishes(&self) -> anyhow::Result<Vec<Self::RelishStoragePath>> {
-        let list_response = self
-            .bucket
-            .list(String::new(), None)
-            .await
-            .context("Failed to list s3 objects")?;
-
-        Ok(list_response
-            .into_iter()
-            .flat_map(|response| response.contents)
-            .map(|s3_object| S3ObjectKey(s3_object.key))
-            .collect())
-    }
-
-    async fn download_relish(
-        &self,
-        from: &Self::RelishStoragePath,
-        to: &Path,
-    ) -> anyhow::Result<()> {
-        let mut target_file = std::fs::OpenOptions::new()
-            .write(true)
-            .open(to)
-            .with_context(|| format!("Failed to open target s3 destination at {}", to.display()))?;
-        let code = self
-            .bucket
-            .get_object_stream(from.key(), &mut target_file)
-            .await
-            .with_context(|| format!("Failed to download s3 object with key {}", from.key()))?;
-        if code != 200 {
-            Err(anyhow::format_err!(
-                "Received non-200 exit code during downloading object from directory, code: {}",
-                code
-            ))
-        } else {
-            Ok(())
-        }
-    }
-
-    async fn delete_relish(&self, path: &Self::RelishStoragePath) -> anyhow::Result<()> {
-        let (_, code) = self
-            .bucket
-            .delete_object(path.key())
-            .await
-            .with_context(|| format!("Failed to delete s3 object with key {}", path.key()))?;
-        if code != 200 {
-            Err(anyhow::format_err!(
-                "Received non-200 exit code during deleting object with key '{}', code: {}",
-                path.key(),
-                code
-            ))
-        } else {
-            Ok(())
-        }
-    }
-
-    async fn upload_relish(&self, from: &Path, to: &Self::RelishStoragePath) -> anyhow::Result<()> {
-        let mut local_file = tokio::fs::OpenOptions::new().read(true).open(from).await?;
-
-        let code = self
-            .bucket
-            .put_object_stream(&mut local_file, to.key())
-            .await
-            .with_context(|| format!("Failed to create s3 object with key {}", to.key()))?;
-        if code != 200 {
-            Err(anyhow::format_err!(
-                "Received non-200 exit code during creating object with key '{}', code: {}",
-                to.key(),
-                code
-            ))
-        } else {
-            Ok(())
-        }
-    }
-}
--- a/pageserver/src/relish_storage/storage_uploader.rs
+++ b/pageserver/src/relish_storage/storage_uploader.rs
@@ -1,116 +0,0 @@
-use std::{
-    collections::VecDeque,
-    path::{Path, PathBuf},
-    sync::{Arc, Mutex},
-    thread,
-};
-
-use zenith_utils::zid::ZTimelineId;
-
-use crate::{relish_storage::RelishStorage, RelishStorageConfig};
-
-use super::{local_fs::LocalFs, rust_s3::RustS3};
-
-pub struct QueueBasedRelishUploader {
-    upload_queue: Arc<Mutex<VecDeque<(ZTimelineId, PathBuf)>>>,
-}
-
-impl QueueBasedRelishUploader {
-    pub fn new(
-        config: &RelishStorageConfig,
-        page_server_workdir: &'static Path,
-    ) -> anyhow::Result<Self> {
-        let upload_queue = Arc::new(Mutex::new(VecDeque::new()));
-        let _handle = match config {
-            RelishStorageConfig::LocalFs(root) => {
-                let relish_storage = LocalFs::new(root.clone())?;
-                create_upload_thread(
-                    Arc::clone(&upload_queue),
-                    relish_storage,
-                    page_server_workdir,
-                )?
-            }
-            RelishStorageConfig::AwsS3(s3_config) => {
-                let relish_storage = RustS3::new(s3_config)?;
-                create_upload_thread(
-                    Arc::clone(&upload_queue),
-                    relish_storage,
-                    page_server_workdir,
-                )?
-            }
-        };
-
-        Ok(Self { upload_queue })
-    }
-
-    pub fn schedule_upload(&self, timeline_id: ZTimelineId, relish_path: PathBuf) {
-        self.upload_queue
-            .lock()
-            .unwrap()
-            .push_back((timeline_id, relish_path))
-    }
-}
-
-fn create_upload_thread<P, S: 'static + RelishStorage<RelishStoragePath = P>>(
-    upload_queue: Arc<Mutex<VecDeque<(ZTimelineId, PathBuf)>>>,
-    relish_storage: S,
-    page_server_workdir: &'static Path,
-) -> std::io::Result<thread::JoinHandle<()>> {
-    let runtime = tokio::runtime::Builder::new_current_thread()
-        .enable_all()
-        .build()?;
-    thread::Builder::new()
-        .name("Queue based relish uploader".to_string())
-        .spawn(move || loop {
-            runtime.block_on(async {
-                upload_loop_step(&upload_queue, &relish_storage, page_server_workdir).await;
-            })
-        })
-}
-
-async fn upload_loop_step<P, S: 'static + RelishStorage<RelishStoragePath = P>>(
-    upload_queue: &Mutex<VecDeque<(ZTimelineId, PathBuf)>>,
-    relish_storage: &S,
-    page_server_workdir: &Path,
-) {
-    let mut queue_accessor = upload_queue.lock().unwrap();
-    log::debug!("current upload queue length: {}", queue_accessor.len());
-    let next_upload = queue_accessor.pop_front();
-    drop(queue_accessor);
-
-    let (relish_timeline_id, relish_local_path) = match next_upload {
-        Some(data) => data,
-        None => {
-            // Don't spin and allow others to use the queue.
-            // In future, could be improved to be more clever about delays depending on relish upload stats
-            thread::sleep(std::time::Duration::from_secs(1));
-            return;
-        }
-    };
-
-    if let Err(e) = upload_relish(relish_storage, page_server_workdir, &relish_local_path).await {
-        log::error!(
-            "Failed to upload relish '{}' for timeline {}, reason: {}",
-            relish_local_path.display(),
-            relish_timeline_id,
-            e
-        );
-        upload_queue
-            .lock()
-            .unwrap()
-            .push_back((relish_timeline_id, relish_local_path))
-    } else {
-        log::debug!("Relish successfully uploaded");
-    }
-}
-
-async fn upload_relish<P, S: RelishStorage<RelishStoragePath = P>>(
-    relish_storage: &S,
-    page_server_workdir: &Path,
-    relish_local_path: &Path,
-) -> anyhow::Result<()> {
-    let destination = S::derive_destination(page_server_workdir, relish_local_path)?;
-    relish_storage
-        .upload_relish(relish_local_path, &destination)
-        .await
-}
--- a/pageserver/src/repository.rs
+++ b/pageserver/src/repository.rs
@@ -17,7 +17,11 @@ pub trait Repository: Send + Sync {
    fn get_timeline(&self, timelineid: ZTimelineId) -> Result<Arc<dyn Timeline>>;

    /// Create a new, empty timeline. The caller is responsible for loading data into it
-    fn create_empty_timeline(&self, timelineid: ZTimelineId) -> Result<Arc<dyn Timeline>>;
+    fn create_empty_timeline(
+        &self,
+        timelineid: ZTimelineId,
+        start_lsn: Lsn,
+    ) -> Result<Arc<dyn Timeline>>;

    /// Branch a timeline
    fn branch_timeline(&self, src: ZTimelineId, dst: ZTimelineId, start_lsn: Lsn) -> Result<()>;
@@ -28,15 +32,22 @@ pub trait Repository: Send + Sync {
    ///
    /// 'timelineid' specifies the timeline to GC, or None for all.
    /// `horizon` specifies delta from last lsn to preserve all object versions (pitr interval).
-    /// `checkpoint_before_gc` parameter is used to force compaction of storage before CG
-    /// to make tests more deterministic.
-    /// TODO Do we still need it or we can call checkpoint explicitly in tests where needed?
+    /// `compact` parameter is used to force compaction of storage.
+    /// some storage implementation are based on lsm tree and require periodic merge (compaction).
+    /// usually storage implementation determines itself when compaction should be performed.
+    /// but for gc tests it way be useful to force compaction just after completion of gc iteration
+    /// to make sure that all detected garbage is removed.
+    /// so right now `compact` is set to true when gc explicitly requested through page srver api,
+    /// and is st to false in gc threads which infinitely repeats gc iterations in loop.
    fn gc_iteration(
        &self,
        timelineid: Option<ZTimelineId>,
        horizon: u64,
-        checkpoint_before_gc: bool,
+        compact: bool,
    ) -> Result<GcResult>;
+
+    // TODO get timelines?
+    //fn get_stats(&self) -> RepositoryStats;
 }

 ///
@@ -48,7 +59,6 @@ pub struct GcResult {
    pub ondisk_relfiles_needed_by_cutoff: u64,
    pub ondisk_relfiles_needed_by_branches: u64,
    pub ondisk_relfiles_not_updated: u64,
-    pub ondisk_relfiles_needed_as_tombstone: u64,
    pub ondisk_relfiles_removed: u64, // # of layer files removed because they have been made obsolete by newer ondisk files.
    pub ondisk_relfiles_dropped: u64, // # of layer files removed because the relation was dropped

@@ -56,7 +66,6 @@ pub struct GcResult {
    pub ondisk_nonrelfiles_needed_by_cutoff: u64,
    pub ondisk_nonrelfiles_needed_by_branches: u64,
    pub ondisk_nonrelfiles_not_updated: u64,
-    pub ondisk_nonrelfiles_needed_as_tombstone: u64,
    pub ondisk_nonrelfiles_removed: u64, // # of layer files removed because they have been made obsolete by newer ondisk files.
    pub ondisk_nonrelfiles_dropped: u64, // # of layer files removed because the relation was dropped

@@ -69,7 +78,6 @@ impl AddAssign for GcResult {
        self.ondisk_relfiles_needed_by_cutoff += other.ondisk_relfiles_needed_by_cutoff;
        self.ondisk_relfiles_needed_by_branches += other.ondisk_relfiles_needed_by_branches;
        self.ondisk_relfiles_not_updated += other.ondisk_relfiles_not_updated;
-        self.ondisk_relfiles_needed_as_tombstone += other.ondisk_relfiles_needed_as_tombstone;
        self.ondisk_relfiles_removed += other.ondisk_relfiles_removed;
        self.ondisk_relfiles_dropped += other.ondisk_relfiles_dropped;

@@ -77,7 +85,6 @@ impl AddAssign for GcResult {
        self.ondisk_nonrelfiles_needed_by_cutoff += other.ondisk_nonrelfiles_needed_by_cutoff;
        self.ondisk_nonrelfiles_needed_by_branches += other.ondisk_nonrelfiles_needed_by_branches;
        self.ondisk_nonrelfiles_not_updated += other.ondisk_nonrelfiles_not_updated;
-        self.ondisk_nonrelfiles_needed_as_tombstone += other.ondisk_nonrelfiles_needed_as_tombstone;
        self.ondisk_nonrelfiles_removed += other.ondisk_nonrelfiles_removed;
        self.ondisk_nonrelfiles_dropped += other.ondisk_nonrelfiles_dropped;

@@ -90,32 +97,23 @@ pub trait Timeline: Send + Sync {
    // Public GET functions
    //------------------------------------------------------------------------------

-    ///
-    /// Wait until WAL has been received and processed up to this LSN.
-    ///
-    /// You should call this before any of the other get_* or list_* functions. Calling
-    /// those functions with an LSN that has been processed yet is an error.
-    ///
-    fn wait_lsn(&self, lsn: Lsn) -> Result<()>;
-
-    /// Look up given page version.
+    /// Look up given page in the cache.
    fn get_page_at_lsn(&self, tag: RelishTag, blknum: u32, lsn: Lsn) -> Result<Bytes>;

+    /// Look up given page in the cache.
+    fn get_page_at_lsn_nowait(&self, tag: RelishTag, blknum: u32, lsn: Lsn) -> Result<Bytes>;
+
    /// Get size of a relish
    fn get_relish_size(&self, tag: RelishTag, lsn: Lsn) -> Result<Option<u32>>;

    /// Does relation exist?
    fn get_rel_exists(&self, tag: RelishTag, lsn: Lsn) -> Result<bool>;

-    /// Get a list of all existing relations
-    /// Pass RelTag to get relation objects or None to get nonrels.
-    fn list_relishes(&self, tag: Option<RelTag>, lsn: Lsn) -> Result<HashSet<RelishTag>>;
+    /// Get a list of all distinct relations in given tablespace and database.
+    fn list_rels(&self, spcnode: u32, dbnode: u32, lsn: Lsn) -> Result<HashSet<RelTag>>;

-    /// Get a list of all existing relations in given tablespace and database.
-    fn list_rels(&self, spcnode: u32, dbnode: u32, lsn: Lsn) -> Result<HashSet<RelishTag>>;
-
-    /// Get a list of all existing non-relational objects
-    fn list_nonrels(&self, lsn: Lsn) -> Result<HashSet<RelishTag>>;
+    /// Get a list of non-relational objects
+    fn list_nonrels<'a>(&'a self, lsn: Lsn) -> Result<HashSet<RelishTag>>;

    //------------------------------------------------------------------------------
    // Public PUT functions, to update the repository with new page versions.
@@ -135,7 +133,7 @@ pub trait Timeline: Send + Sync {
    /// Truncate relation
    fn put_truncation(&self, rel: RelishTag, lsn: Lsn, nblocks: u32) -> Result<()>;

-    /// This method is used for marking dropped relations and truncated SLRU files and aborted two phase records
+    /// This method is used for marking dropped relations and truncated SLRU files
    fn drop_relish(&self, tag: RelishTag, lsn: Lsn) -> Result<()>;

    /// Track end of the latest digested WAL record.
@@ -148,7 +146,6 @@ pub trait Timeline: Send + Sync {
    /// Get last or prev record separately. Same as get_last_record_rlsn().last/prev.
    fn get_last_record_lsn(&self) -> Lsn;
    fn get_prev_record_lsn(&self) -> Lsn;
-    fn get_start_lsn(&self) -> Lsn;

    ///
    /// Flush to disk all data that was written with the put_* functions
@@ -156,16 +153,14 @@ pub trait Timeline: Send + Sync {
    /// NOTE: This has nothing to do with checkpoint in PostgreSQL. We don't
    /// know anything about them here in the repository.
    fn checkpoint(&self) -> Result<()>;
+}

-    /// Retrieve current logical size of the timeline
-    ///
-    /// NOTE: counted incrementally, includes ancestors,
-    /// doesnt support TwoPhase relishes yet
-    fn get_current_logical_size(&self) -> usize;
-
-    /// Does the same as get_current_logical_size but counted on demand.
-    /// Used in tests to ensure thet incremental and non incremental variants match.
-    fn get_current_logical_size_non_incremental(&self, lsn: Lsn) -> Result<usize>;
+#[derive(Clone)]
+pub struct RepositoryStats {
+    pub num_entries: Lsn,
+    pub num_page_images: Lsn,
+    pub num_wal_records: Lsn,
+    pub num_getpage_requests: Lsn,
 }

 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
@@ -205,7 +200,6 @@ impl WALRecord {
 ///
 /// Tests that should work the same with any Repository/Timeline implementation.
 ///
-#[allow(clippy::bool_assert_comparison)]
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -213,9 +207,11 @@ mod tests {
    use crate::walredo::{WalRedoError, WalRedoManager};
    use crate::PageServerConf;
    use postgres_ffi::pg_constants;
-    use postgres_ffi::xlog_utils::SIZEOF_CHECKPOINT;
    use std::fs;
+    use std::path::PathBuf;
    use std::str::FromStr;
+    use std::time::Duration;
+    use zenith_utils::postgres_backend::AuthType;
    use zenith_utils::zid::ZTenantId;

    /// Arbitrary relation tag, for testing.
@@ -232,6 +228,8 @@ mod tests {
        forknum: 0,
    });

+    const TESTDB: u32 = 111;
+
    /// Convenience function to create a page image with given string as the only content
    #[allow(non_snake_case)]
    fn TEST_IMG(s: &str) -> Bytes {
@@ -242,24 +240,26 @@ mod tests {
        buf.freeze()
    }

-    fn assert_current_logical_size(timeline: &Arc<dyn Timeline>, lsn: Lsn) {
-        let incremental = timeline.get_current_logical_size();
-        let non_incremental = timeline
-            .get_current_logical_size_non_incremental(lsn)
-            .unwrap();
-        assert_eq!(incremental, non_incremental);
-    }
-
    static ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; 8192]);
-    static ZERO_CHECKPOINT: Bytes = Bytes::from_static(&[0u8; SIZEOF_CHECKPOINT]);

    fn get_test_repo(test_name: &str) -> Result<Box<dyn Repository>> {
-        let repo_dir = PageServerConf::test_repo_dir(test_name);
+        let repo_dir = PathBuf::from(format!("../tmp_check/test_{}", test_name));
        let _ = fs::remove_dir_all(&repo_dir);
        fs::create_dir_all(&repo_dir)?;
        fs::create_dir_all(&repo_dir.join("timelines"))?;

-        let conf = PageServerConf::dummy_conf(repo_dir);
+        let conf = PageServerConf {
+            daemonize: false,
+            gc_horizon: 64 * 1024 * 1024,
+            gc_period: Duration::from_secs(10),
+            listen_addr: "127.0.0.1:5430".to_string(),
+            http_endpoint_addr: "127.0.0.1:9898".to_string(),
+            superuser: "zenith_admin".to_string(),
+            workdir: repo_dir,
+            pg_distrib_dir: "".into(),
+            auth_type: AuthType::Trust,
+            auth_validation_public_key_path: None,
+        };
        // Make a static copy of the config. This can never be free'd, but that's
        // OK in a test.
        let conf: &'static PageServerConf = Box::leak(Box::new(conf));
@@ -285,7 +285,7 @@ mod tests {

        // Create timeline to work on
        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
+        let tline = repo.create_empty_timeline(timelineid, Lsn(0x00))?;

        tline.put_page_image(TESTREL_A, 0, Lsn(0x20), TEST_IMG("foo blk 0 at 2"))?;
        tline.put_page_image(TESTREL_A, 0, Lsn(0x20), TEST_IMG("foo blk 0 at 2"))?;
@@ -295,8 +295,6 @@ mod tests {

        tline.advance_last_record_lsn(Lsn(0x50));

-        assert_current_logical_size(&tline, Lsn(0x50));
-
        // The relation was created at LSN 2, not visible at LSN 1 yet.
        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x10))?, false);
        assert!(tline.get_relish_size(TESTREL_A, Lsn(0x10))?.is_none());
@@ -341,7 +339,6 @@ mod tests {
        // Truncate last block
        tline.put_truncation(TESTREL_A, Lsn(0x60), 2)?;
        tline.advance_last_record_lsn(Lsn(0x60));
-        assert_current_logical_size(&tline, Lsn(0x60));

        // Check reported size and contents after truncation
        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x60))?.unwrap(), 2);
@@ -361,175 +358,6 @@ mod tests {
            TEST_IMG("foo blk 2 at 5")
        );

-        // Truncate to zero length
-        tline.put_truncation(TESTREL_A, Lsn(0x68), 0)?;
-        tline.advance_last_record_lsn(Lsn(0x68));
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x68))?.unwrap(), 0);
-
-        // Extend from 0 to 2 blocks, leaving a gap
-        tline.put_page_image(TESTREL_A, 1, Lsn(0x70), TEST_IMG("foo blk 1"))?;
-        tline.advance_last_record_lsn(Lsn(0x70));
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x70))?.unwrap(), 2);
-        assert_eq!(tline.get_page_at_lsn(TESTREL_A, 0, Lsn(0x70))?, ZERO_PAGE);
-        assert_eq!(
-            tline.get_page_at_lsn(TESTREL_A, 1, Lsn(0x70))?,
-            TEST_IMG("foo blk 1")
-        );
-
-        // Extend a lot more, leaving a big gap that spans across segments
-        // FIXME: This is currently broken, see https://github.com/zenithdb/zenith/issues/500
-        /*
-        tline.put_page_image(TESTREL_A, 1500, Lsn(0x80), TEST_IMG("foo blk 1500"))?;
-        tline.advance_last_record_lsn(Lsn(0x80));
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x80))?.unwrap(), 1501);
-        for blk in 2..1500 {
-            assert_eq!(
-                tline.get_page_at_lsn(TESTREL_A, blk, Lsn(0x80))?,
-                ZERO_PAGE);
-        }
-        assert_eq!(
-            tline.get_page_at_lsn(TESTREL_A, 1500, Lsn(0x80))?,
-            TEST_IMG("foo blk 1500"));
-         */
-
-        Ok(())
-    }
-
-    // Test what happens if we dropped a relation
-    // and then created it again within the same layer.
-    #[test]
-    fn test_drop_extend() -> Result<()> {
-        let repo = get_test_repo("test_drop_extend")?;
-
-        // Create timeline to work on
-        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
-
-        tline.put_page_image(TESTREL_A, 0, Lsn(0x20), TEST_IMG("foo blk 0 at 2"))?;
-        tline.advance_last_record_lsn(Lsn(0x20));
-
-        // Check that rel exists and size is correct
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x20))?, true);
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x20))?.unwrap(), 1);
-
-        // Drop relish
-        tline.drop_relish(TESTREL_A, Lsn(0x30))?;
-        tline.advance_last_record_lsn(Lsn(0x30));
-
-        // Check that rel is not visible anymore
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x30))?, false);
-        assert!(tline.get_relish_size(TESTREL_A, Lsn(0x30))?.is_none());
-
-        // Extend it again
-        tline.put_page_image(TESTREL_A, 0, Lsn(0x40), TEST_IMG("foo blk 0 at 4"))?;
-        tline.advance_last_record_lsn(Lsn(0x40));
-
-        // Check that rel exists and size is correct
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x40))?, true);
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x40))?.unwrap(), 1);
-
-        Ok(())
-    }
-
-    // Test what happens if we truncated a relation
-    // so that one of its segments was dropped
-    // and then extended it again within the same layer.
-    #[test]
-    fn test_truncate_extend() -> Result<()> {
-        let repo = get_test_repo("test_truncate_extend")?;
-
-        // Create timeline to work on
-        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
-
-        //from storage_layer.rs
-        const RELISH_SEG_SIZE: u32 = 10 * 1024 * 1024 / 8192;
-        let relsize = RELISH_SEG_SIZE * 2;
-
-        // Create relation with relsize blocks
-        for blkno in 0..relsize {
-            let lsn = Lsn(0x20);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            tline.put_page_image(TESTREL_A, blkno, lsn, TEST_IMG(&data))?;
-        }
-
-        tline.advance_last_record_lsn(Lsn(0x20));
-
-        // The relation was created at LSN 2, not visible at LSN 1 yet.
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x10))?, false);
-        assert!(tline.get_relish_size(TESTREL_A, Lsn(0x10))?.is_none());
-
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x20))?, true);
-        assert_eq!(
-            tline.get_relish_size(TESTREL_A, Lsn(0x20))?.unwrap(),
-            relsize
-        );
-
-        // Check relation content
-        for blkno in 0..relsize {
-            let lsn = Lsn(0x20);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            assert_eq!(
-                tline.get_page_at_lsn(TESTREL_A, blkno, lsn)?,
-                TEST_IMG(&data)
-            );
-        }
-
-        // Truncate relation so that second segment was dropped
-        // - only leave one page
-        tline.put_truncation(TESTREL_A, Lsn(0x60), 1)?;
-        tline.advance_last_record_lsn(Lsn(0x60));
-
-        // Check reported size and contents after truncation
-        assert_eq!(tline.get_relish_size(TESTREL_A, Lsn(0x60))?.unwrap(), 1);
-
-        for blkno in 0..1 {
-            let lsn = Lsn(0x20);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            assert_eq!(
-                tline.get_page_at_lsn(TESTREL_A, blkno, Lsn(0x60))?,
-                TEST_IMG(&data)
-            );
-        }
-
-        // should still see all blocks with older LSN
-        assert_eq!(
-            tline.get_relish_size(TESTREL_A, Lsn(0x50))?.unwrap(),
-            relsize
-        );
-        for blkno in 0..relsize {
-            let lsn = Lsn(0x20);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            assert_eq!(
-                tline.get_page_at_lsn(TESTREL_A, blkno, Lsn(0x50))?,
-                TEST_IMG(&data)
-            );
-        }
-
-        // Extend relation again.
-        // Add enough blocks to create second segment
-        for blkno in 0..relsize {
-            let lsn = Lsn(0x80);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            tline.put_page_image(TESTREL_A, blkno, lsn, TEST_IMG(&data))?;
-        }
-        tline.advance_last_record_lsn(Lsn(0x80));
-
-        assert_eq!(tline.get_rel_exists(TESTREL_A, Lsn(0x80))?, true);
-        assert_eq!(
-            tline.get_relish_size(TESTREL_A, Lsn(0x80))?.unwrap(),
-            relsize
-        );
-        // Check relation content
-        for blkno in 0..relsize {
-            let lsn = Lsn(0x80);
-            let data = format!("foo blk {} at {}", blkno, lsn);
-            assert_eq!(
-                tline.get_page_at_lsn(TESTREL_A, blkno, Lsn(0x80))?,
-                TEST_IMG(&data)
-            );
-        }
-
        Ok(())
    }

@@ -539,7 +367,7 @@ mod tests {
    fn test_large_rel() -> Result<()> {
        let repo = get_test_repo("test_large_rel")?;
        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
+        let tline = repo.create_empty_timeline(timelineid, Lsn(0x00))?;

        let mut lsn = 0x10;
        for blknum in 0..pg_constants::RELSEG_SIZE + 1 {
@@ -549,8 +377,6 @@ mod tests {
        }
        tline.advance_last_record_lsn(Lsn(lsn));

-        assert_current_logical_size(&tline, Lsn(lsn));
-
        assert_eq!(
            tline.get_relish_size(TESTREL_A, Lsn(lsn))?.unwrap(),
            pg_constants::RELSEG_SIZE + 1
@@ -564,7 +390,6 @@ mod tests {
            tline.get_relish_size(TESTREL_A, Lsn(lsn))?.unwrap(),
            pg_constants::RELSEG_SIZE
        );
-        assert_current_logical_size(&tline, Lsn(lsn));

        // Truncate another block
        lsn += 0x10;
@@ -574,7 +399,6 @@ mod tests {
            tline.get_relish_size(TESTREL_A, Lsn(lsn))?.unwrap(),
            pg_constants::RELSEG_SIZE - 1
        );
-        assert_current_logical_size(&tline, Lsn(lsn));

        // Truncate to 1500, and then truncate all the way down to 0, one block at a time
        // This tests the behavior at segment boundaries
@@ -590,63 +414,53 @@ mod tests {

            size -= 1;
        }
-        assert_current_logical_size(&tline, Lsn(lsn));

        Ok(())
    }

    ///
-    /// Test list_rels() function, with branches and dropped relations
+    /// Test list_rels() function, with branches and unlinking
    ///
    #[test]
-    fn test_list_rels_drop() -> Result<()> {
-        let repo = get_test_repo("test_list_rels_drop")?;
+    fn test_list_rels_and_unlink() -> Result<()> {
+        let repo = get_test_repo("test_unlink")?;
        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
-        const TESTDB: u32 = 111;
+        let tline = repo.create_empty_timeline(timelineid, Lsn(0x00))?;

        // Import initial dummy checkpoint record, otherwise the get_timeline() call
        // after branching fails below
-        tline.put_page_image(RelishTag::Checkpoint, 0, Lsn(0x10), ZERO_CHECKPOINT.clone())?;
+        tline.put_page_image(RelishTag::Checkpoint, 0, Lsn(0x10), ZERO_PAGE.clone())?;

        // Create a relation on the timeline
        tline.put_page_image(TESTREL_A, 0, Lsn(0x20), TEST_IMG("foo blk 0 at 2"))?;

-        tline.advance_last_record_lsn(Lsn(0x30));
-
-        // Check that list_rels() lists it after LSN 2, but no before it
-        assert!(!tline.list_rels(0, TESTDB, Lsn(0x10))?.contains(&TESTREL_A));
-        assert!(tline.list_rels(0, TESTDB, Lsn(0x20))?.contains(&TESTREL_A));
-        assert!(tline.list_rels(0, TESTDB, Lsn(0x30))?.contains(&TESTREL_A));
+        // Check that list_rels() lists it after LSN 2, but no before it.
+        let reltag = match TESTREL_A {
+            RelishTag::Relation(reltag) => reltag,
+            _ => panic!("unexpected relish")
+        };
+        assert!(!tline.list_rels(0, TESTDB, Lsn(0x10))?.contains(&reltag));
+        assert!(tline.list_rels(0, TESTDB, Lsn(0x20))?.contains(&reltag));
+        assert!(tline.list_rels(0, TESTDB, Lsn(0x30))?.contains(&reltag));

        // Create a branch, check that the relation is visible there
        let newtimelineid = ZTimelineId::from_str("AA223344556677881122334455667788").unwrap();
        repo.branch_timeline(timelineid, newtimelineid, Lsn(0x30))?;
        let newtline = repo.get_timeline(newtimelineid)?;

-        assert!(newtline
-            .list_rels(0, TESTDB, Lsn(0x30))?
-            .contains(&TESTREL_A));
+        assert!(newtline.list_rels(0, TESTDB, Lsn(0x30))?.contains(&reltag));

-        // Drop it on the branch
+        // Unlink it on the branch
        newtline.drop_relish(TESTREL_A, Lsn(0x40))?;
-        newtline.advance_last_record_lsn(Lsn(0x40));

-        // Check that it's no longer listed on the branch after the point where it was dropped
-        assert!(newtline
-            .list_rels(0, TESTDB, Lsn(0x30))?
-            .contains(&TESTREL_A));
-        assert!(!newtline
-            .list_rels(0, TESTDB, Lsn(0x40))?
-            .contains(&TESTREL_A));
+        // Check that it's no longer listed on the branch after the point where it was unlinked
+        assert!(newtline.list_rels(0, TESTDB, Lsn(0x30))?.contains(&reltag));
+        assert!(!newtline.list_rels(0, TESTDB, Lsn(0x40))?.contains(&reltag));

        // Run checkpoint and garbage collection and check that it's still not visible
        newtline.checkpoint()?;
        repo.gc_iteration(Some(newtimelineid), 0, true)?;
-
-        assert!(!newtline
-            .list_rels(0, TESTDB, Lsn(0x40))?
-            .contains(&TESTREL_A));
+        assert!(!newtline.list_rels(0, TESTDB, Lsn(0x40))?.contains(&reltag));

        Ok(())
    }
@@ -658,11 +472,11 @@ mod tests {
    fn test_branch() -> Result<()> {
        let repo = get_test_repo("test_branch")?;
        let timelineid = ZTimelineId::from_str("11223344556677881122334455667788").unwrap();
-        let tline = repo.create_empty_timeline(timelineid)?;
+        let tline = repo.create_empty_timeline(timelineid, Lsn(0x00))?;

        // Import initial dummy checkpoint record, otherwise the get_timeline() call
        // after branching fails below
-        tline.put_page_image(RelishTag::Checkpoint, 0, Lsn(0x10), ZERO_CHECKPOINT.clone())?;
+        tline.put_page_image(RelishTag::Checkpoint, 0, Lsn(0x10), ZERO_PAGE.clone())?;

        // Create a relation on the timeline
        tline.put_page_image(TESTREL_A, 0, Lsn(0x20), TEST_IMG("foo blk 0 at 2"))?;
@@ -673,7 +487,6 @@ mod tests {
        tline.put_page_image(TESTREL_B, 0, Lsn(0x20), TEST_IMG("foobar blk 0 at 2"))?;

        tline.advance_last_record_lsn(Lsn(0x40));
-        assert_current_logical_size(&tline, Lsn(0x40));

        // Branch the history, modify relation differently on the new timeline
        let newtimelineid = ZTimelineId::from_str("AA223344556677881122334455667788").unwrap();
@@ -701,8 +514,6 @@ mod tests {

        assert_eq!(newtline.get_relish_size(TESTREL_B, Lsn(0x40))?.unwrap(), 1);

-        assert_current_logical_size(&tline, Lsn(0x40));
-
        Ok(())
    }

--- a/pageserver/src/restore_local_repo.rs
+++ b/pageserver/src/restore_local_repo.rs
@@ -9,7 +9,9 @@ use std::cmp::min;
 use std::fs;
 use std::fs::File;
 use std::io::Read;
-use std::path::Path;
+use std::io::Seek;
+use std::io::SeekFrom;
+use std::path::{Path, PathBuf};

 use anyhow::Result;
 use bytes::{Buf, Bytes};
@@ -27,7 +29,7 @@ use zenith_utils::lsn::Lsn;
 const MAX_MBR_BLKNO: u32 =
    pg_constants::MAX_MULTIXACT_ID / pg_constants::MULTIXACT_MEMBERS_PER_PAGE as u32;

-static ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; 8192]);
+const ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; 8192]);

 ///
 /// Import all relation data pages from local disk into the repository.
@@ -44,7 +46,13 @@ pub fn import_timeline_from_postgres_datadir(
            None => continue,

            Some("pg_control") => {
-                import_control_file(timeline, lsn, &direntry.path())?;
+                import_nonrel_file(timeline, lsn, RelishTag::ControlFile, &direntry.path())?;
+                // Extract checkpoint record from pg_control and store is as separate object
+                let pg_control_bytes =
+                    timeline.get_page_at_lsn_nowait(RelishTag::ControlFile, 0, lsn)?;
+                let pg_control = ControlFileData::decode(&pg_control_bytes)?;
+                let checkpoint_bytes = pg_control.checkPointCopy.encode();
+                timeline.put_page_image(RelishTag::Checkpoint, 0, lsn, checkpoint_bytes)?;
            }
            Some("pg_filenode.map") => import_nonrel_file(
                timeline,
@@ -120,12 +128,13 @@ pub fn import_timeline_from_postgres_datadir(
    }
    for entry in fs::read_dir(path.join("pg_twophase"))? {
        let entry = entry?;
-        let xid = u32::from_str_radix(entry.path().to_str().unwrap(), 16)?;
+        let xid = u32::from_str_radix(&entry.path().to_str().unwrap(), 16)?;
        import_nonrel_file(timeline, lsn, RelishTag::TwoPhase { xid }, &entry.path())?;
    }
    // TODO: Scan pg_tblspc

-    timeline.advance_last_record_lsn(lsn);
+    timeline.advance_last_record_lsn(lsn.align());
+    timeline.checkpoint()?;

    Ok(())
 }
@@ -207,35 +216,6 @@ fn import_nonrel_file(
    Ok(())
 }

-///
-/// Import pg_control file into the repository.
-///
-/// The control file is imported as is, but we also extract the checkpoint record
-/// from it and store it separated.
-fn import_control_file(timeline: &dyn Timeline, lsn: Lsn, path: &Path) -> Result<()> {
-    let mut file = File::open(path)?;
-    let mut buffer = Vec::new();
-    // read the whole file
-    file.read_to_end(&mut buffer)?;
-
-    info!("importing control file {}", path.display());
-
-    // Import it as ControlFile
-    timeline.put_page_image(
-        RelishTag::ControlFile,
-        0,
-        lsn,
-        Bytes::copy_from_slice(&buffer[..]),
-    )?;
-
-    // Extract the checkpoint record and import it separately.
-    let pg_control = ControlFileData::decode(&buffer)?;
-    let checkpoint_bytes = pg_control.checkPointCopy.encode();
-    timeline.put_page_image(RelishTag::Checkpoint, 0, lsn, checkpoint_bytes)?;
-
-    Ok(())
-}
-
 ///
 /// Import an SLRU segment file
 ///
@@ -281,6 +261,86 @@ fn import_slru_file(timeline: &dyn Timeline, lsn: Lsn, slru: SlruKind, path: &Pa
    Ok(())
 }

+/// Scan PostgreSQL WAL files in given directory
+/// and load all records >= 'startpoint' into the repository.
+pub fn import_timeline_wal(walpath: &Path, timeline: &dyn Timeline, startpoint: Lsn) -> Result<()> {
+    let mut waldecoder = WalStreamDecoder::new(startpoint);
+
+    let mut segno = startpoint.segment_number(pg_constants::WAL_SEGMENT_SIZE);
+    let mut offset = startpoint.segment_offset(pg_constants::WAL_SEGMENT_SIZE);
+    let mut last_lsn = startpoint;
+
+    let checkpoint_bytes = timeline.get_page_at_lsn_nowait(RelishTag::Checkpoint, 0, startpoint)?;
+    let mut checkpoint = CheckPoint::decode(&checkpoint_bytes)?;
+
+    loop {
+        // FIXME: assume postgresql tli 1 for now
+        let filename = XLogFileName(1, segno, pg_constants::WAL_SEGMENT_SIZE);
+        let mut buf = Vec::new();
+
+        //Read local file
+        let mut path = walpath.join(&filename);
+
+        // It could be as .partial
+        if !PathBuf::from(&path).exists() {
+            path = walpath.join(filename + ".partial");
+        }
+
+        // Slurp the WAL file
+        let open_result = File::open(&path);
+        if let Err(e) = &open_result {
+            if e.kind() == std::io::ErrorKind::NotFound {
+                break;
+            }
+        }
+        let mut file = open_result?;
+
+        if offset > 0 {
+            file.seek(SeekFrom::Start(offset as u64))?;
+        }
+
+        let nread = file.read_to_end(&mut buf)?;
+        if nread != pg_constants::WAL_SEGMENT_SIZE - offset as usize {
+            // Maybe allow this for .partial files?
+            error!("read only {} bytes from WAL file", nread);
+        }
+
+        waldecoder.feed_bytes(&buf);
+
+        let mut nrecords = 0;
+        loop {
+            let rec = waldecoder.poll_decode();
+            if rec.is_err() {
+                // Assume that an error means we've reached the end of
+                // a partial WAL record. So that's ok.
+                trace!("WAL decoder error {:?}", rec);
+                break;
+            }
+            if let Some((lsn, recdata)) = rec.unwrap() {
+                let decoded = decode_wal_record(recdata.clone());
+                save_decoded_record(&mut checkpoint, timeline, &decoded, recdata, lsn)?;
+                last_lsn = lsn;
+            } else {
+                break;
+            }
+            nrecords += 1;
+        }
+
+        info!("imported {} records up to {}", nrecords, last_lsn);
+
+        segno += 1;
+        offset = 0;
+    }
+
+    info!("reached end of WAL at {}", last_lsn);
+    let checkpoint_bytes = checkpoint.encode();
+    timeline.put_page_image(RelishTag::Checkpoint, 0, last_lsn, checkpoint_bytes)?;
+
+    timeline.advance_last_record_lsn(last_lsn.align());
+    timeline.checkpoint()?;
+    Ok(())
+}
+
 ///
 /// Helper function to parse a WAL record and call the Timeline's PUT functions for all the
 /// relations/pages that the record affects.
@@ -332,14 +392,10 @@ pub fn save_decoded_record(
        {
            let dropdb = XlDropDatabase::decode(&mut buf);

-            // To drop the database, we need to drop all the relations in it. Like in
-            // save_xlog_dbase_create(), use the previous record's LSN in the list_rels() call
-            let req_lsn = min(timeline.get_last_record_lsn(), lsn);
-
            for tablespace_id in dropdb.tablespace_ids {
-                let rels = timeline.list_rels(tablespace_id, dropdb.db_id, req_lsn)?;
+                let rels = timeline.list_rels(tablespace_id, dropdb.db_id, lsn)?;
                for rel in rels {
-                    timeline.drop_relish(rel, lsn)?;
+                    timeline.drop_relish(RelishTag::Relation(rel), lsn)?;
                }
                trace!(
                    "Drop FileNodeMap {}, {} at lsn {}",
@@ -371,7 +427,7 @@ pub fn save_decoded_record(
                },
                rpageno,
                lsn,
-                ZERO_PAGE.clone(),
+                ZERO_PAGE,
            )?;
        } else {
            assert!(info == pg_constants::CLOG_TRUNCATE);
@@ -428,7 +484,7 @@ pub fn save_decoded_record(
                },
                rpageno,
                lsn,
-                ZERO_PAGE.clone(),
+                ZERO_PAGE,
            )?;
        } else if info == pg_constants::XLOG_MULTIXACT_ZERO_MEM_PAGE {
            let pageno = buf.get_u32_le();
@@ -441,7 +497,7 @@ pub fn save_decoded_record(
                },
                rpageno,
                lsn,
-                ZERO_PAGE.clone(),
+                ZERO_PAGE,
            )?;
        } else if info == pg_constants::XLOG_MULTIXACT_CREATE_ID {
            let xlrec = XlMultiXactCreate::decode(&mut buf);
@@ -476,6 +532,9 @@ pub fn save_decoded_record(
            }
        }
    }
+    // Now that this record has been handled, let the repository know that
+    // it is up-to-date to this LSN
+    timeline.advance_last_record_lsn(lsn.align());
    Ok(())
 }

@@ -499,52 +558,56 @@ fn save_xlog_dbase_create(timeline: &dyn Timeline, lsn: Lsn, rec: &XlCreateDatab

    let mut num_rels_copied = 0;
    let mut num_blocks_copied = 0;
-    for rel in rels {
-        if let RelishTag::Relation(src_rel) = rel {
-            assert_eq!(src_rel.spcnode, src_tablespace_id);
-            assert_eq!(src_rel.dbnode, src_db_id);
+    for src_rel in rels {
+        assert_eq!(src_rel.spcnode, src_tablespace_id);
+        assert_eq!(src_rel.dbnode, src_db_id);

-            let nblocks = timeline.get_relish_size(rel, req_lsn)?.unwrap_or(0);
-            let dst_rel = RelTag {
-                spcnode: tablespace_id,
-                dbnode: db_id,
-                relnode: src_rel.relnode,
-                forknum: src_rel.forknum,
-            };
+        let nblocks = timeline
+            .get_relish_size(RelishTag::Relation(src_rel), req_lsn)?
+            .unwrap_or(0);
+        let dst_rel = RelTag {
+            spcnode: tablespace_id,
+            dbnode: db_id,
+            relnode: src_rel.relnode,
+            forknum: src_rel.forknum,
+        };

-            // Copy content
-            for blknum in 0..nblocks {
-                let content = timeline.get_page_at_lsn(rel, blknum, req_lsn)?;
+        // Copy content
+        for blknum in 0..nblocks {
+            let content =
+                timeline.get_page_at_lsn_nowait(RelishTag::Relation(src_rel), blknum, req_lsn)?;

-                debug!("copying block {} from {} to {}", blknum, src_rel, dst_rel);
+            debug!("copying block {} from {} to {}", blknum, src_rel, dst_rel);

-                timeline.put_page_image(RelishTag::Relation(dst_rel), blknum, lsn, content)?;
-                num_blocks_copied += 1;
-            }
-
-            if nblocks == 0 {
-                // make sure we have some trace of the relation, even if it's empty
-                timeline.put_truncation(RelishTag::Relation(dst_rel), lsn, 0)?;
-            }
-
-            num_rels_copied += 1;
+            timeline.put_page_image(RelishTag::Relation(dst_rel), blknum, lsn, content)?;
+            num_blocks_copied += 1;
        }
+
+        if nblocks == 0 {
+            // make sure we have some trace of the relation, even if it's empty
+            timeline.put_truncation(RelishTag::Relation(dst_rel), lsn, 0)?;
+        }
+
+        num_rels_copied += 1;
    }

    // Copy relfilemap
    // TODO This implementation is very inefficient -
    // it scans all non-rels only to find FileNodeMaps
    for tag in timeline.list_nonrels(req_lsn)? {
-        if let RelishTag::FileNodeMap { spcnode, dbnode } = tag {
-            if spcnode == src_tablespace_id && dbnode == src_db_id {
-                let img = timeline.get_page_at_lsn(tag, 0, req_lsn)?;
-                let new_tag = RelishTag::FileNodeMap {
-                    spcnode: tablespace_id,
-                    dbnode: db_id,
-                };
-                timeline.put_page_image(new_tag, 0, lsn, img)?;
-                break;
+        match tag {
+            RelishTag::FileNodeMap { spcnode, dbnode } => {
+                if spcnode == src_tablespace_id && dbnode == src_db_id {
+                    let img = timeline.get_page_at_lsn_nowait(tag, 0, req_lsn)?;
+                    let new_tag = RelishTag::FileNodeMap {
+                        spcnode: tablespace_id,
+                        dbnode: db_id,
+                    };
+                    timeline.put_page_image(new_tag, 0, lsn, img)?;
+                    break;
+                }
            }
+            _ => {} // do nothing
        }
    }
    info!(
@@ -720,14 +783,17 @@ fn save_clog_truncate_record(
    // instead.
    let req_lsn = min(timeline.get_last_record_lsn(), lsn);
    for obj in timeline.list_nonrels(req_lsn)? {
-        if let RelishTag::Slru { slru, segno } = obj {
-            if slru == SlruKind::Clog {
-                let segpage = segno * pg_constants::SLRU_PAGES_PER_SEGMENT;
-                if slru_may_delete_clogsegment(segpage, xlrec.pageno) {
-                    timeline.drop_relish(RelishTag::Slru { slru, segno }, lsn)?;
-                    trace!("Drop CLOG segment {:>04X} at lsn {}", segno, lsn);
+        match obj {
+            RelishTag::Slru { slru, segno } => {
+                if slru == SlruKind::Clog {
+                    let segpage = segno * pg_constants::SLRU_PAGES_PER_SEGMENT;
+                    if slru_may_delete_clogsegment(segpage, xlrec.pageno) {
+                        timeline.drop_relish(RelishTag::Slru { slru, segno }, lsn)?;
+                        trace!("Drop CLOG segment {:>04X} at lsn {}", segno, lsn);
+                    }
                }
            }
+            _ => {}
        }
    }

--- a/pageserver/src/tenant_mgr.rs
+++ b/pageserver/src/tenant_mgr.rs
@@ -3,17 +3,17 @@

 use crate::branches;
 use crate::layered_repository::LayeredRepository;
-use crate::repository::{Repository, Timeline};
+use crate::repository::Repository;
 use crate::walredo::PostgresRedoManager;
 use crate::PageServerConf;
-use anyhow::{anyhow, bail, Context, Result};
+use anyhow::{anyhow, bail, Result};
 use lazy_static::lazy_static;
 use log::info;
 use std::collections::HashMap;
 use std::fs;
 use std::str::FromStr;
 use std::sync::{Arc, Mutex};
-use zenith_utils::zid::{ZTenantId, ZTimelineId};
+use zenith_utils::zid::ZTenantId;

 lazy_static! {
    pub static ref REPOSITORY: Mutex<HashMap<ZTenantId, Arc<dyn Repository>>> =
@@ -37,7 +37,6 @@ pub fn init(conf: &'static PageServerConf) {
            tenantid,
        ));
        LayeredRepository::launch_checkpointer_thread(conf, repo.clone());
-        LayeredRepository::launch_gc_thread(conf, repo.clone());

        info!("initialized storage for tenant: {}", &tenantid);
        m.insert(tenantid, repo);
@@ -67,18 +66,9 @@ pub fn insert_repository_for_tenant(tenantid: ZTenantId, repo: Arc<dyn Repositor
    o.insert(tenantid, repo);
 }

-pub fn get_repository_for_tenant(tenantid: ZTenantId) -> Result<Arc<dyn Repository>> {
+pub fn get_repository_for_tenant(tenantid: &ZTenantId) -> Result<Arc<dyn Repository>> {
    let o = &REPOSITORY.lock().unwrap();
-    o.get(&tenantid)
+    o.get(tenantid)
        .map(|repo| Arc::clone(repo))
        .ok_or_else(|| anyhow!("repository not found for tenant name {}", tenantid))
 }
-
-pub fn get_timeline_for_tenant(
-    tenantid: ZTenantId,
-    timelineid: ZTimelineId,
-) -> Result<Arc<dyn Timeline>> {
-    get_repository_for_tenant(tenantid)?
-        .get_timeline(timelineid)
-        .with_context(|| format!("cannot fetch timeline {}", timelineid))
-}
--- a/pageserver/src/waldecoder.rs
+++ b/pageserver/src/waldecoder.rs
@@ -54,11 +54,6 @@ impl WalStreamDecoder {
        }
    }

-    // The latest LSN position fed to the decoder.
-    pub fn available(&self) -> Lsn {
-        self.lsn + self.inputbuf.remaining() as u64
-    }
-
    pub fn feed_bytes(&mut self, buf: &[u8]) {
        self.inputbuf.extend_from_slice(buf);
    }
@@ -164,19 +159,9 @@ impl WalStreamDecoder {
                    let recordbuf = recordbuf.freeze();
                    let mut buf = recordbuf.clone();

-                    let xlogrec = XLogRecord::from_bytes(&mut buf);
-
                    // XLOG_SWITCH records are special. If we see one, we need to skip
                    // to the next WAL segment.
-                    if xlogrec.is_xlog_switch_record() {
-                        trace!("saw xlog switch record at {}", self.lsn);
-                        self.padlen =
-                            self.lsn.calc_padding(pg_constants::WAL_SEGMENT_SIZE as u64) as u32;
-                    } else {
-                        // Pad to an 8-byte boundary
-                        self.padlen = self.lsn.calc_padding(8u32) as u32;
-                    }
-
+                    let xlogrec = XLogRecord::from_bytes(&mut buf);
                    let mut crc = crc32c_append(0, &recordbuf[XLOG_RECORD_CRC_OFFS + 4..]);
                    crc = crc32c_append(crc, &recordbuf[0..XLOG_RECORD_CRC_OFFS]);
                    if crc != xlogrec.xl_crc {
@@ -185,6 +170,14 @@ impl WalStreamDecoder {
                            lsn: self.lsn,
                        });
                    }
+                    if xlogrec.is_xlog_switch_record() {
+                        trace!("saw xlog switch record at {}", self.lsn);
+                        self.padlen =
+                            self.lsn.calc_padding(pg_constants::WAL_SEGMENT_SIZE as u64) as u32;
+                    } else {
+                        // Pad to an 8-byte boundary
+                        self.padlen = self.lsn.calc_padding(8u32) as u32;
+                    }

                    // Always align resulting LSN on 0x8 boundary -- that is important for getPage()
                    // and WalReceiver integration. Since this code is used both for WalReceiver and
@@ -204,7 +197,6 @@ impl WalStreamDecoder {
 }

 #[allow(dead_code)]
-#[derive(Default)]
 pub struct DecodedBkpBlock {
    /* Is this block ref in use? */
    //in_use: bool,
@@ -237,7 +229,25 @@ pub struct DecodedBkpBlock {

 impl DecodedBkpBlock {
    pub fn new() -> DecodedBkpBlock {
-        Default::default()
+        DecodedBkpBlock {
+            rnode_spcnode: 0,
+            rnode_dbnode: 0,
+            rnode_relnode: 0,
+            forknum: 0,
+            blkno: 0,
+
+            flags: 0,
+            has_image: false,
+            apply_image: false,
+            will_init: false,
+            hole_offset: 0,
+            hole_length: 0,
+            bimg_len: 0,
+            bimg_info: 0,
+
+            has_data: false,
+            data_len: 0,
+        }
    }
 }

--- a/pageserver/src/walreceiver.rs
+++ b/pageserver/src/walreceiver.rs
@@ -23,6 +23,8 @@ use postgres_types::PgLsn;
 use std::cmp::{max, min};
 use std::collections::HashMap;
 use std::fs;
+use std::fs::{File, OpenOptions};
+use std::io::{Seek, SeekFrom, Write};
 use std::str::FromStr;
 use std::sync::Mutex;
 use std::thread;
@@ -64,13 +66,10 @@ pub fn launch_wal_receiver(
            receivers.insert(timelineid, receiver);

            // Also launch a new thread to handle this connection
-            //
-            // NOTE: This thread name is checked in the assertion in wait_lsn. If you change
-            // this, make sure you update the assertion too.
            let _walreceiver_thread = thread::Builder::new()
                .name("WAL receiver thread".into())
                .spawn(move || {
-                    thread_main(conf, timelineid, tenantid);
+                    thread_main(conf, timelineid, &tenantid);
                })
                .unwrap();
        }
@@ -91,7 +90,7 @@ fn get_wal_producer_connstr(timelineid: ZTimelineId) -> String {
 //
 // This is the entry point for the WAL receiver thread.
 //
-fn thread_main(conf: &'static PageServerConf, timelineid: ZTimelineId, tenantid: ZTenantId) {
+fn thread_main(conf: &'static PageServerConf, timelineid: ZTimelineId, tenantid: &ZTenantId) {
    info!(
        "WAL receiver thread started for timeline : '{}'",
        timelineid
@@ -121,7 +120,7 @@ fn walreceiver_main(
    conf: &PageServerConf,
    timelineid: ZTimelineId,
    wal_producer_connstr: &str,
-    tenantid: ZTenantId,
+    tenantid: &ZTenantId,
 ) -> Result<(), Error> {
    // Connect to the database in replication mode.
    info!("connecting to {:?}", wal_producer_connstr);
@@ -147,7 +146,8 @@ fn walreceiver_main(
    let end_of_wal = Lsn::from(u64::from(identify.xlogpos));
    let mut caught_up = false;

-    let timeline = tenant_mgr::get_timeline_for_tenant(tenantid, timelineid)?;
+    let repository = tenant_mgr::get_repository_for_tenant(tenantid)?;
+    let timeline = repository.get_timeline(timelineid).unwrap();

    //
    // Start streaming the WAL, from where we left off previously.
@@ -164,7 +164,7 @@ fn walreceiver_main(
    // There might be some padding after the last full record, skip it.
    startpoint += startpoint.calc_padding(8u32);

-    info!(
+    debug!(
        "last_record_lsn {} starting replication from {} for timeline {}, server is at {}...",
        last_rec_lsn, startpoint, timelineid, end_of_wal
    );
@@ -176,7 +176,7 @@ fn walreceiver_main(

    let mut waldecoder = WalStreamDecoder::new(startpoint);

-    let checkpoint_bytes = timeline.get_page_at_lsn(RelishTag::Checkpoint, 0, startpoint)?;
+    let checkpoint_bytes = timeline.get_page_at_lsn_nowait(RelishTag::Checkpoint, 0, startpoint)?;
    let mut checkpoint = CheckPoint::decode(&checkpoint_bytes)?;
    trace!("CheckPoint.nextXid = {}", checkpoint.nextXid.value);

@@ -190,6 +190,15 @@ fn walreceiver_main(
                let endlsn = startlsn + data.len() as u64;
                let prev_last_rec_lsn = last_rec_lsn;

+                write_wal_file(
+                    conf,
+                    startlsn,
+                    &timelineid,
+                    pg_constants::WAL_SEGMENT_SIZE,
+                    data,
+                    tenantid,
+                )?;
+
                trace!("received XLogData between {} and {}", startlsn, endlsn);

                waldecoder.feed_bytes(data);
@@ -211,6 +220,7 @@ fn walreceiver_main(
                        recdata,
                        lsn,
                    )?;
+                    last_rec_lsn = lsn;

                    let new_checkpoint_bytes = checkpoint.encode();
                    // Check if checkpoint data was updated by save_decoded_record
@@ -222,11 +232,6 @@ fn walreceiver_main(
                            new_checkpoint_bytes,
                        )?;
                    }
-
-                    // Now that this record has been fully handled, including updating the
-                    // checkpoint data, let the repository know that it is up-to-date to this LSN
-                    timeline.advance_last_record_lsn(lsn);
-                    last_rec_lsn = lsn;
                }

                // Somewhat arbitrarily, if we have at least 10 complete wal segments (16 MB each),
@@ -248,7 +253,7 @@ fn walreceiver_main(
                        &timelineid,
                        pg_constants::WAL_SEGMENT_SIZE,
                        last_rec_lsn,
-                        &tenantid,
+                        tenantid,
                    )?;

                    if newest_segno - oldest_segno >= 10 {
@@ -349,9 +354,6 @@ fn find_wal_file_range(
 ///
 /// [postgres docs]: https://www.postgresql.org/docs/current/protocol-replication.html
 #[derive(Debug)]
-// As of nightly 2021-09-11, fields that are only read by the type's `Debug` impl still count as
-// unused. Relevant issue: https://github.com/rust-lang/rust/issues/88900
-#[allow(dead_code)]
 pub struct IdentifySystem {
    systemid: u64,
    timeline: u32,
@@ -392,3 +394,98 @@ pub fn identify_system(client: &mut Client) -> Result<IdentifySystem, Error> {
        Err(IdentifyError.into())
    }
 }
+
+fn write_wal_file(
+    conf: &PageServerConf,
+    startpos: Lsn,
+    timelineid: &ZTimelineId,
+    wal_seg_size: usize,
+    buf: &[u8],
+    tenantid: &ZTenantId,
+) -> anyhow::Result<()> {
+    let mut bytes_left: usize = buf.len();
+    let mut bytes_written: usize = 0;
+    let mut partial;
+    let mut start_pos = startpos;
+    const ZERO_BLOCK: &[u8] = &[0u8; XLOG_BLCKSZ];
+
+    let wal_dir = conf.wal_dir_path(timelineid, tenantid);
+
+    /* Extract WAL location for this block */
+    let mut xlogoff = start_pos.segment_offset(wal_seg_size);
+
+    while bytes_left != 0 {
+        let bytes_to_write;
+
+        /*
+         * If crossing a WAL boundary, only write up until we reach wal
+         * segment size.
+         */
+        if xlogoff + bytes_left > wal_seg_size {
+            bytes_to_write = wal_seg_size - xlogoff;
+        } else {
+            bytes_to_write = bytes_left;
+        }
+
+        /* Open file */
+        let segno = start_pos.segment_number(wal_seg_size);
+        let wal_file_name = XLogFileName(
+            1, // FIXME: always use Postgres timeline 1
+            segno,
+            wal_seg_size,
+        );
+        let wal_file_path = wal_dir.join(wal_file_name.clone());
+        let wal_file_partial_path = wal_dir.join(wal_file_name.clone() + ".partial");
+
+        {
+            let mut wal_file: File;
+            /* Try to open already completed segment */
+            if let Ok(file) = OpenOptions::new().write(true).open(&wal_file_path) {
+                wal_file = file;
+                partial = false;
+            } else if let Ok(file) = OpenOptions::new().write(true).open(&wal_file_partial_path) {
+                /* Try to open existed partial file */
+                wal_file = file;
+                partial = true;
+            } else {
+                /* Create and fill new partial file */
+                partial = true;
+                match OpenOptions::new()
+                    .create(true)
+                    .write(true)
+                    .open(&wal_file_partial_path)
+                {
+                    Ok(mut file) => {
+                        for _ in 0..(wal_seg_size / XLOG_BLCKSZ) {
+                            file.write_all(&ZERO_BLOCK)?;
+                        }
+                        wal_file = file;
+                    }
+                    Err(e) => {
+                        error!("Failed to open log file {:?}: {}", &wal_file_path, e);
+                        return Err(e.into());
+                    }
+                }
+            }
+            wal_file.seek(SeekFrom::Start(xlogoff as u64))?;
+            wal_file.write_all(&buf[bytes_written..(bytes_written + bytes_to_write)])?;
+
+            // FIXME: Flush the file
+            //wal_file.sync_all()?;
+        }
+        /* Write was successful, advance our position */
+        bytes_written += bytes_to_write;
+        bytes_left -= bytes_to_write;
+        start_pos += bytes_to_write as u64;
+        xlogoff += bytes_to_write;
+
+        /* Did we reach the end of a WAL segment? */
+        if start_pos.segment_offset(wal_seg_size) == 0 {
+            xlogoff = 0;
+            if partial {
+                fs::rename(&wal_file_partial_path, &wal_file_path)?;
+            }
+        }
+    }
+    Ok(())
+}
--- a/pageserver/src/walredo.rs
+++ b/pageserver/src/walredo.rs
@@ -22,7 +22,8 @@ use byteorder::{ByteOrder, LittleEndian};
 use bytes::{Buf, BufMut, Bytes, BytesMut};
 use lazy_static::lazy_static;
 use log::*;
-use serde::Serialize;
+use serde::{Deserialize, Serialize};
+use std::cell::RefCell;
 use std::fs;
 use std::fs::OpenOptions;
 use std::io::prelude::*;
@@ -59,7 +60,7 @@ use postgres_ffi::XLogRecord;
 /// In Postgres `BufferTag` structure is used for exactly the same purpose.
 /// [See more related comments here](https://github.com/postgres/postgres/blob/99c5852e20a0987eca1c38ba0c09329d4076b6a0/src/include/storage/buf_internals.h#L91).
 ///
-#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Serialize)]
+#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Serialize, Deserialize)]
 pub struct BufferTag {
    pub rel: RelTag,
    pub blknum: u32,
@@ -205,10 +206,10 @@ impl WalRedoManager for PostgresRedoManager {
                    .block_on(PostgresRedoProcess::launch(self.conf, &self.tenantid))?;
                *process_guard = Some(p);
            }
-            let process = process_guard.as_mut().unwrap();
+            let process = (*process_guard).as_ref().unwrap();

            self.runtime
-                .block_on(self.handle_apply_request(process, &request))
+                .block_on(self.handle_apply_request(&process, &request))
        };
        end_time = Instant::now();

@@ -246,7 +247,7 @@ impl PostgresRedoManager {
    ///
    async fn handle_apply_request(
        &self,
-        process: &mut PostgresRedoProcess,
+        process: &PostgresRedoProcess,
        request: &WalRedoRequest,
    ) -> Result<Bytes, WalRedoError> {
        let rel = request.rel;
@@ -323,7 +324,7 @@ impl PostgresRedoManager {
                            if rec_segno == segno && blknum == rpageno {
                                transaction_id_set_status(
                                    *subxact,
-                                    pg_constants::TRANSACTION_STATUS_COMMITTED,
+                                    pg_constants::TRANSACTION_STATUS_SUB_COMMITTED,
                                    &mut page,
                                );
                            }
@@ -437,8 +438,8 @@ impl PostgresRedoManager {
 /// Handle to the Postgres WAL redo process
 ///
 struct PostgresRedoProcess {
-    stdin: ChildStdin,
-    stdout: ChildStdout,
+    stdin: RefCell<ChildStdin>,
+    stdout: RefCell<ChildStdout>,
 }

 impl PostgresRedoProcess {
@@ -452,7 +453,7 @@ impl PostgresRedoProcess {
        // FIXME: We need a dummy Postgres cluster to run the process in. Currently, we
        // just create one with constant name. That fails if you try to launch more than
        // one WAL redo manager concurrently.
-        let datadir = conf.tenant_path(tenantid).join("wal-redo-datadir");
+        let datadir = conf.tenant_path(&tenantid).join("wal-redo-datadir");

        // Create empty data directory for wal-redo postgres, deleting old one first.
        if datadir.exists() {
@@ -531,7 +532,10 @@ impl PostgresRedoProcess {
        };
        tokio::spawn(f_stderr);

-        Ok(PostgresRedoProcess { stdin, stdout })
+        Ok(PostgresRedoProcess {
+            stdin: RefCell::new(stdin),
+            stdout: RefCell::new(stdout),
+        })
    }

    //
@@ -539,14 +543,13 @@ impl PostgresRedoProcess {
    // new page image.
    //
    async fn apply_wal_records(
-        &mut self,
+        &self,
        tag: BufferTag,
        base_img: Option<Bytes>,
        records: &[WALRecord],
    ) -> Result<Bytes, std::io::Error> {
-        let stdout = &mut self.stdout;
-        // Buffer the writes to avoid a lot of small syscalls.
-        let mut stdin = tokio::io::BufWriter::new(&mut self.stdin);
+        let mut stdin = self.stdin.borrow_mut();
+        let mut stdout = self.stdout.borrow_mut();

        // We do three things simultaneously: send the old base image and WAL records to
        // the child process's stdin, read the result from child's stdout, and forward any logging
--- a/postgres_ffi/src/controlfile_utils.rs
+++ b/postgres_ffi/src/controlfile_utils.rs
@@ -11,7 +11,7 @@
 //! data directory is compatible with a postgres binary. That includes
 //! a version number, configuration options that can be set at
 //! compilation time like the block size, and the platform's alignment
-//! and endianness information. (The PostgreSQL on-disk file format is
+//! and endianess information. (The PostgreSQL on-disk file format is
 //! not portable across platforms.)
 //!
 //! The control file is stored in the PostgreSQL data directory, as
@@ -58,7 +58,7 @@ impl ControlFileData {
        let expectedcrc = crc32c::crc32c(&buf[0..OFFSETOF_CRC]);

        // Use serde to deserialize the input as a ControlFileData struct.
-        let controlfile = ControlFileData::des_prefix(buf)?;
+        let controlfile = ControlFileData::des(buf)?;

        // Check the CRC
        if expectedcrc != controlfile.crc {
--- a/postgres_ffi/src/lib.rs
+++ b/postgres_ffi/src/lib.rs
@@ -32,5 +32,5 @@ pub const fn transaction_id_precedes(id1: TransactionId, id2: TransactionId) ->
    }

    let diff = id1.wrapping_sub(id2) as i32;
-    diff < 0
+    return diff < 0;
 }
--- a/postgres_ffi/src/pg_constants.rs
+++ b/postgres_ffi/src/pg_constants.rs
@@ -189,11 +189,11 @@ pub const XLOG_CHECKPOINT_SHUTDOWN: u8 = 0x00;
 pub const XLOG_CHECKPOINT_ONLINE: u8 = 0x10;
 pub const XLP_LONG_HEADER: u16 = 0x0002;

-pub const PG_MAJORVERSION: &str = "14";
+pub const PG_MAJORVERSION: &'static str = "14";

 // List of subdirectories inside pgdata.
 // Copied from src/bin/initdb/initdb.c
-pub const PGDATA_SUBDIRS: [&str; 22] = [
+pub const PGDATA_SUBDIRS: [&'static str; 22] = [
    "global",
    "pg_wal/archive_status",
    "pg_commit_ts",
@@ -218,11 +218,11 @@ pub const PGDATA_SUBDIRS: [&str; 22] = [
    "pg_logical/mappings",
 ];

-// Don't include postgresql.conf as it is inconvenient on node start:
-// we need postgresql.conf before basebackup to synchronize safekeepers
-// so no point in overwriting it during backup restore. Rest of the files
-// here are not needed before backup so it is okay to edit them after.
-pub const PGDATA_SPECIAL_FILES: [&str; 3] =
-    ["pg_hba.conf", "pg_ident.conf", "postgresql.auto.conf"];
+pub const PGDATA_SPECIAL_FILES: [&'static str; 4] = [
+    "pg_hba.conf",
+    "pg_ident.conf",
+    "postgresql.conf",
+    "postgresql.auto.conf",
+];

-pub static PG_HBA: &str = include_str!("../samples/pg_hba.conf");
+pub static PG_HBA: &'static str = include_str!("../samples/pg_hba.conf");
--- a/postgres_ffi/src/xlog_utils.rs
+++ b/postgres_ffi/src/xlog_utils.rs
@@ -16,20 +16,16 @@ use crate::XLogPageHeaderData;
 use crate::XLogRecord;
 use crate::XLOG_PAGE_MAGIC;

-use anyhow::{bail, Result};
 use byteorder::{ByteOrder, LittleEndian};
 use bytes::{Buf, Bytes};
 use bytes::{BufMut, BytesMut};
 use crc32c::*;
 use log::*;
-use std::cmp::max;
 use std::cmp::min;
 use std::fs::{self, File};
 use std::io::prelude::*;
-use std::io::SeekFrom;
 use std::path::{Path, PathBuf};
 use std::time::SystemTime;
-use zenith_utils::lsn::Lsn;

 pub const XLOG_FNAME_LEN: usize = 24;
 pub const XLOG_BLCKSZ: usize = 8192;
@@ -41,7 +37,6 @@ pub const MAX_SEND_SIZE: usize = XLOG_BLCKSZ * 16;
 pub const XLOG_SIZE_OF_XLOG_SHORT_PHD: usize = std::mem::size_of::<XLogPageHeaderData>();
 pub const XLOG_SIZE_OF_XLOG_LONG_PHD: usize = std::mem::size_of::<XLogLongPageHeaderData>();
 pub const XLOG_SIZE_OF_XLOG_RECORD: usize = std::mem::size_of::<XLogRecord>();
-#[allow(clippy::identity_op)]
 pub const SIZE_OF_XLOG_RECORD_DATA_HEADER_SHORT: usize = 1 * 2;

 pub type XLogRecPtr = u64;
@@ -93,21 +88,6 @@ pub fn IsPartialXLogFileName(fname: &str) -> bool {
    fname.ends_with(".partial") && IsXLogFileName(&fname[0..fname.len() - 8])
 }

-/// If LSN points to the beginning of the page, then shift it to first record,
-/// otherwise align on 8-bytes boundary (required for WAL records)
-pub fn normalize_lsn(lsn: Lsn, seg_sz: usize) -> Lsn {
-    if lsn.0 % XLOG_BLCKSZ as u64 == 0 {
-        let hdr_size = if lsn.0 % seg_sz as u64 == 0 {
-            XLOG_SIZE_OF_XLOG_LONG_PHD
-        } else {
-            XLOG_SIZE_OF_XLOG_SHORT_PHD
-        };
-        lsn + hdr_size as u64
-    } else {
-        lsn.align()
-    }
-}
-
 pub fn get_current_timestamp() -> TimestampTz {
    const UNIX_EPOCH_JDATE: u64 = 2440588; /* == date2j(1970, 1, 1) */
    const POSTGRES_EPOCH_JDATE: u64 = 2451545; /* == date2j(2000, 1, 1) */
@@ -128,10 +108,8 @@ fn find_end_of_wal_segment(
    segno: XLogSegNo,
    tli: TimeLineID,
    wal_seg_size: usize,
-    start_offset: usize, // start reading at this point
-) -> Result<u32> {
-    // step back to the beginning of the page to read it in...
-    let mut offs: usize = start_offset - start_offset % XLOG_BLCKSZ;
+) -> u32 {
+    let mut offs: usize = 0;
    let mut contlen: usize = 0;
    let mut wal_crc: u32 = 0;
    let mut crc: u32 = 0;
@@ -140,33 +118,24 @@ fn find_end_of_wal_segment(
    let file_name = XLogFileName(tli, segno, wal_seg_size);
    let mut last_valid_rec_pos: usize = 0;
    let mut file = File::open(data_dir.join(file_name.clone() + ".partial")).unwrap();
-    file.seek(SeekFrom::Start(offs as u64))?;
    let mut rec_hdr = [0u8; XLOG_RECORD_CRC_OFFS];

    while offs < wal_seg_size {
        // we are at the beginning of the page; read it in
        if offs % XLOG_BLCKSZ == 0 {
-            let bytes_read = file.read(&mut buf)?;
-            if bytes_read != buf.len() {
-                bail!(
-                    "failed to read {} bytes from {} at {}",
-                    XLOG_BLCKSZ,
-                    file_name,
-                    offs
-                );
+            if let Ok(bytes_read) = file.read(&mut buf) {
+                if bytes_read != buf.len() {
+                    break;
+                }
+            } else {
+                break;
            }
-
            let xlp_magic = LittleEndian::read_u16(&buf[0..2]);
            let xlp_info = LittleEndian::read_u16(&buf[2..4]);
            let xlp_rem_len = LittleEndian::read_u32(&buf[XLP_REM_LEN_OFFS..XLP_REM_LEN_OFFS + 4]);
-            // this is expected in current usage when valid WAL starts after page header
            if xlp_magic != XLOG_PAGE_MAGIC as u16 {
-                trace!(
-                    "invalid WAL file {}.partial magic {} at {:?}",
-                    file_name,
-                    xlp_magic,
-                    Lsn(XLogSegNoOffsetToRecPtr(segno, offs as u32, wal_seg_size)),
-                );
+                info!("Invalid WAL file {}.partial magic {}", file_name, xlp_magic);
+                break;
            }
            if offs == 0 {
                offs = XLOG_SIZE_OF_XLOG_LONG_PHD;
@@ -176,18 +145,11 @@ fn find_end_of_wal_segment(
            } else {
                offs += XLOG_SIZE_OF_XLOG_SHORT_PHD;
            }
-            // ... and step forward again if asked
-            offs = max(offs, start_offset);
-
        // beginning of the next record
        } else if contlen == 0 {
            let page_offs = offs % XLOG_BLCKSZ;
            let xl_tot_len = LittleEndian::read_u32(&buf[page_offs..page_offs + 4]) as usize;
            if xl_tot_len == 0 {
-                info!(
-                    "find_end_of_wal_segment reached zeros at {:?}",
-                    Lsn(XLogSegNoOffsetToRecPtr(segno, offs as u32, wal_seg_size))
-                );
                break; // zeros, reached the end
            }
            last_valid_rec_pos = offs;
@@ -211,11 +173,12 @@ fn find_end_of_wal_segment(
                let crc_offs = page_offs - rec_offs + XLOG_RECORD_CRC_OFFS;
                wal_crc = LittleEndian::read_u32(&buf[crc_offs..crc_offs + 4]);
                crc = crc32c_append(0, &buf[crc_offs + 4..page_offs + n]);
+                crc = !crc;
            } else {
                crc ^= 0xFFFFFFFFu32;
                crc = crc32c_append(crc, &buf[page_offs..page_offs + n]);
+                crc = !crc;
            }
-            crc = !crc;
            rec_offs += n;
            offs += n;
            contlen -= n;
@@ -238,7 +201,7 @@ fn find_end_of_wal_segment(
            }
        }
    }
-    Ok(last_valid_rec_pos as u32)
+    last_valid_rec_pos as u32
 }

 ///
@@ -251,8 +214,7 @@ pub fn find_end_of_wal(
    data_dir: &Path,
    wal_seg_size: usize,
    precise: bool,
-    start_lsn: Lsn, // start reading WAL at this point or later
-) -> Result<(XLogRecPtr, TimeLineID)> {
+) -> (XLogRecPtr, TimeLineID) {
    let mut high_segno: XLogSegNo = 0;
    let mut high_tli: TimeLineID = 0;
    let mut high_ispartial = false;
@@ -294,32 +256,19 @@ pub fn find_end_of_wal(
            high_segno += 1;
        } else if precise {
            /* otherwise locate last record in last partial segment */
-            if start_lsn.segment_number(wal_seg_size) > high_segno {
-                bail!(
-                    "provided start_lsn {:?} is beyond highest segno {:?} available",
-                    start_lsn,
-                    high_segno,
-                );
-            }
-            high_offs = find_end_of_wal_segment(
-                data_dir,
-                high_segno,
-                high_tli,
-                wal_seg_size,
-                start_lsn.segment_offset(wal_seg_size),
-            )?;
+            high_offs = find_end_of_wal_segment(data_dir, high_segno, high_tli, wal_seg_size);
        }
        let high_ptr = XLogSegNoOffsetToRecPtr(high_segno, high_offs, wal_seg_size);
-        return Ok((high_ptr, high_tli));
+        return (high_ptr, high_tli);
    }
-    Ok((0, 0))
+    (0, 0)
 }

 pub fn main() {
    let mut data_dir = PathBuf::new();
    data_dir.push(".");
    let wal_seg_size = 16 * 1024 * 1024;
-    let (wal_end, tli) = find_end_of_wal(&data_dir, wal_seg_size, true, Lsn(0)).unwrap();
+    let (wal_end, tli) = find_end_of_wal(&data_dir, wal_seg_size, true);
    println!(
        "wal_end={:>08X}{:>08X}, tli={}",
        (wal_end >> 32) as u32,
@@ -467,6 +416,7 @@ mod tests {
    use super::*;
    use regex::Regex;
    use std::{env, process::Command, str::FromStr};
+    use zenith_utils::lsn::Lsn;

    // Run find_end_of_wal against file in test_wal dir
    // Ensure that it finds last record correctly
@@ -498,7 +448,7 @@ mod tests {
        let wal_seg_size = 16 * 1024 * 1024;

        // 3. Check end_of_wal on non-partial WAL segment (we treat it as fully populated)
-        let (wal_end, tli) = find_end_of_wal(&wal_dir, wal_seg_size, true, Lsn(0)).unwrap();
+        let (wal_end, tli) = find_end_of_wal(&wal_dir, wal_seg_size, true);
        let wal_end = Lsn(wal_end);
        println!("wal_end={}, tli={}", wal_end, tli);
        assert_eq!(wal_end, "0/2000000".parse::<Lsn>().unwrap());
@@ -515,7 +465,7 @@ mod tests {
        let waldump_output = std::str::from_utf8(&waldump_output.stderr).unwrap();
        println!("waldump_output = '{}'", &waldump_output);
        let re = Regex::new(r"invalid record length at (.+):").unwrap();
-        let caps = re.captures(waldump_output).unwrap();
+        let caps = re.captures(&waldump_output).unwrap();
        let waldump_wal_end = Lsn::from_str(caps.get(1).unwrap().as_str()).unwrap();

        // 5. Rename file to partial to actually find last valid lsn
@@ -524,7 +474,7 @@ mod tests {
            wal_dir.join("000000010000000000000001.partial"),
        )
        .unwrap();
-        let (wal_end, tli) = find_end_of_wal(&wal_dir, wal_seg_size, true, Lsn(0)).unwrap();
+        let (wal_end, tli) = find_end_of_wal(&wal_dir, wal_seg_size, true);
        let wal_end = Lsn(wal_end);
        println!("wal_end={}, tli={}", wal_end, tli);
        assert_eq!(wal_end, waldump_wal_end);
--- a/proxy/Cargo.toml
+++ b/proxy/Cargo.toml
@@ -14,10 +14,9 @@ rand = "0.8.3"
 hex = "0.4.3"
 serde = "1"
 serde_json = "1"
-tokio = "1.11"
-tokio-postgres = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
+tokio = { version = "1.7.1", features = ["full"] }
+tokio-postgres = "0.7.2"
 clap = "2.33.0"
 rustls = "0.19.1"
-reqwest = { version = "0.11", features = ["blocking", "json"] }

 zenith_utils = { path = "../zenith_utils" }
--- a/proxy/src/cplane_api.rs
+++ b/proxy/src/cplane_api.rs
@@ -1,12 +1,15 @@
 use anyhow::{bail, Result};
 use serde::{Deserialize, Serialize};
-use std::net::{IpAddr, SocketAddr};
+use std::{
+    collections::HashMap,
+    net::{IpAddr, SocketAddr},
+};

 pub struct CPlaneApi {
-    auth_endpoint: &'static str,
+    // address: SocketAddr,
 }

-#[derive(Serialize, Deserialize, Debug)]
+#[derive(Serialize, Deserialize)]
 pub struct DatabaseInfo {
    pub host: IpAddr, // TODO: allow host name here too
    pub port: u16,
@@ -28,33 +31,62 @@ impl DatabaseInfo {
    }
 }

+// mock cplane api
 impl CPlaneApi {
-    pub fn new(auth_endpoint: &'static str) -> CPlaneApi {
-        CPlaneApi { auth_endpoint }
+    pub fn new(_address: &SocketAddr) -> CPlaneApi {
+        CPlaneApi {
+            // address: address.clone(),
+        }
    }

-    pub fn authenticate_proxy_request(
-        &self,
-        user: &str,
-        md5_response: &[u8],
-        salt: &[u8; 4],
-    ) -> Result<DatabaseInfo> {
-        let mut url = reqwest::Url::parse(self.auth_endpoint)?;
-        url.query_pairs_mut()
-            .append_pair("login", user)
-            .append_pair("md5response", std::str::from_utf8(md5_response)?)
-            .append_pair("salt", &hex::encode(salt));
+    pub fn check_auth(&self, user: &str, md5_response: &[u8], salt: &[u8; 4]) -> Result<()> {
+        // passwords for both is "mypass"
+        let auth_map: HashMap<_, &str> = vec![
+            ("stas@zenith", "716ee6e1c4a9364d66285452c47402b1"),
+            ("stas2@zenith", "3996f75df64c16a8bfaf01301b61d582"),
+        ]
+        .into_iter()
+        .collect();

-        println!("cplane request: {}", url.as_str());
+        let stored_hash = auth_map
+            .get(&user)
+            .ok_or_else(|| anyhow::Error::msg("user not found"))?;
+        let salted_stored_hash = format!(
+            "md5{:x}",
+            md5::compute([stored_hash.as_bytes(), salt].concat())
+        );

-        let resp = reqwest::blocking::get(url)?;
+        let received_hash = std::str::from_utf8(&md5_response)?;

-        if resp.status().is_success() {
-            let conn_info: DatabaseInfo = serde_json::from_str(resp.text()?.as_str())?;
-            println!("got conn info: #{:?}", conn_info);
-            Ok(conn_info)
+        println!(
+            "auth: {} rh={} sh={} ssh={} {:?}",
+            user, received_hash, stored_hash, salted_stored_hash, salt
+        );
+
+        if received_hash == salted_stored_hash {
+            Ok(())
        } else {
            bail!("Auth failed")
        }
    }
+
+    pub fn get_database_uri(&self, _user: &str, _database: &str) -> Result<DatabaseInfo> {
+        Ok(DatabaseInfo {
+            host: "127.0.0.1".parse()?,
+            port: 5432,
+            dbname: "stas".to_string(),
+            user: "stas".to_string(),
+            password: "mypass".to_string(),
+        })
+    }
+
+    // pub fn create_database(&self, _user: &String, _database: &String) -> Result<DatabaseInfo> {
+    //     Ok(DatabaseInfo {
+    //         host: "127.0.0.1".parse()?,
+    //         port: 5432,
+    //         dbname: "stas".to_string(),
+    //         user: "stas".to_string(),
+    //         password: "mypass".to_string(),
+    //     })
+    // }
 }
--- a/proxy/src/main.rs
+++ b/proxy/src/main.rs
@@ -34,7 +34,7 @@ pub struct ProxyConf {
    pub redirect_uri: String,

    /// control plane address where we would check auth.
-    pub auth_endpoint: String,
+    pub cplane_address: SocketAddr,

    pub ssl_config: Option<Arc<ServerConfig>>,
 }
@@ -56,7 +56,8 @@ fn configure_ssl(arg_matches: &ArgMatches) -> anyhow::Result<Option<Arc<ServerCo

    let key = {
        let key_bytes = std::fs::read(key_path).context("SSL key file")?;
-        let mut keys = pemfile::pkcs8_private_keys(&mut &key_bytes[..])
+        let mut keys = pemfile::rsa_private_keys(&mut &key_bytes[..])
+            .or_else(|_| pemfile::pkcs8_private_keys(&mut &key_bytes[..]))
            .map_err(|_| anyhow!("couldn't read TLS keys"))?;
        ensure!(keys.len() == 1, "keys.len() = {} (should be 1)", keys.len());
        keys.pop().unwrap()
@@ -101,14 +102,6 @@ fn main() -> anyhow::Result<()> {
                .help("redirect unauthenticated users to given uri")
                .default_value("http://localhost:3000/psql_session/"),
        )
-        .arg(
-            Arg::with_name("auth-endpoint")
-                .short("a")
-                .long("auth-endpoint")
-                .takes_value(true)
-                .help("redirect unauthenticated users to given uri")
-                .default_value("http://localhost:3000/authenticate_proxy_request/"),
-        )
        .arg(
            Arg::with_name("ssl-key")
                .short("k")
@@ -129,7 +122,7 @@ fn main() -> anyhow::Result<()> {
        proxy_address: arg_matches.value_of("proxy").unwrap().parse()?,
        mgmt_address: arg_matches.value_of("mgmt").unwrap().parse()?,
        redirect_uri: arg_matches.value_of("uri").unwrap().parse()?,
-        auth_endpoint: arg_matches.value_of("auth-endpoint").unwrap().parse()?,
+        cplane_address: "127.0.0.1:3000".parse()?,
        ssl_config: configure_ssl(&arg_matches)?,
    };
    let state = ProxyState {
@@ -150,10 +143,10 @@ fn main() -> anyhow::Result<()> {
        // for each connection.
        thread::Builder::new()
            .name("Proxy thread".into())
-            .spawn(move || proxy::thread_main(state, pageserver_listener))?,
+            .spawn(move || proxy::thread_main(&state, pageserver_listener))?,
        thread::Builder::new()
            .name("Mgmt thread".into())
-            .spawn(move || mgmt::thread_main(state, mgmt_listener))?,
+            .spawn(move || mgmt::thread_main(&state, mgmt_listener))?,
    ];

    for t in threads.into_iter() {
--- a/proxy/src/mgmt.rs
+++ b/proxy/src/mgmt.rs
@@ -5,7 +5,7 @@ use std::{

 use anyhow::bail;
 use bytes::Bytes;
-use serde::Deserialize;
+use serde::{Deserialize, Serialize};
 use zenith_utils::{
    postgres_backend::{self, query_from_cstring, AuthType, PostgresBackend},
    pq_proto::{BeMessage, SINGLE_COL_ROWDESC},
@@ -49,7 +49,7 @@ struct MgmtHandler {
 //             "host": "127.0.0.1",
 //             "port": 5432,
 //             "dbname": "stas",
-//             "user": "stas",
+//             "user": "stas"
 //             "password": "mypass"
 //         }
 //     }
@@ -60,16 +60,13 @@ struct MgmtHandler {
 //         "Failure": "oops"
 //     }
 // }
-//
-// // to test manually by sending a query to mgmt interface:
-// psql -h 127.0.0.1 -p 9999 -c '{"session_id":"4f10dde522e14739","result":{"Success":{"host":"127.0.0.1","port":5432,"dbname":"stas","user":"stas","password":"stas"}}}'
-#[derive(Deserialize)]
+#[derive(Serialize, Deserialize)]
 pub struct PsqlSessionResponse {
    session_id: String,
    result: PsqlSessionResult,
 }

-#[derive(Deserialize)]
+#[derive(Serialize, Deserialize)]
 pub enum PsqlSessionResult {
    Success(DatabaseInfo),
    Failure(String),
@@ -81,47 +78,34 @@ impl postgres_backend::Handler for MgmtHandler {
        pgb: &mut PostgresBackend,
        query_string: Bytes,
    ) -> anyhow::Result<()> {
-        let res = try_process_query(self, pgb, query_string);
-        // intercept and log error message
-        if res.is_err() {
-            println!("Mgmt query failed: #{:?}", res);
-        }
-        res
-    }
-}
+        let query_string = query_from_cstring(query_string);

-fn try_process_query(
-    mgmt: &mut MgmtHandler,
-    pgb: &mut PostgresBackend,
-    query_string: Bytes,
-) -> anyhow::Result<()> {
-    let query_string = query_from_cstring(query_string);
+        println!("Got mgmt query: '{}'", std::str::from_utf8(&query_string)?);

-    println!("Got mgmt query: '{}'", std::str::from_utf8(&query_string)?);
+        let resp: PsqlSessionResponse = serde_json::from_slice(&query_string)?;

-    let resp: PsqlSessionResponse = serde_json::from_slice(&query_string)?;
+        let waiters = self.state.waiters.lock().unwrap();

-    let waiters = mgmt.state.waiters.lock().unwrap();
+        let sender = waiters
+            .get(&resp.session_id)
+            .ok_or_else(|| anyhow::Error::msg("psql_session_id is not found"))?;

-    let sender = waiters
-        .get(&resp.session_id)
-        .ok_or_else(|| anyhow::Error::msg("psql_session_id is not found"))?;
+        match resp.result {
+            PsqlSessionResult::Success(db_info) => {
+                sender.send(Ok(db_info))?;

-    match resp.result {
-        PsqlSessionResult::Success(db_info) => {
-            sender.send(Ok(db_info))?;
+                pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
+                    .write_message_noflush(&BeMessage::DataRow(&[Some(b"ok")]))?
+                    .write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
+                pgb.flush()?;
+                Ok(())
+            }

-            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
-                .write_message_noflush(&BeMessage::DataRow(&[Some(b"ok")]))?
-                .write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
-            pgb.flush()?;
-            Ok(())
-        }
+            PsqlSessionResult::Failure(message) => {
+                sender.send(Err(anyhow::Error::msg(message.clone())))?;

-        PsqlSessionResult::Failure(message) => {
-            sender.send(Err(anyhow::Error::msg(message.clone())))?;
-
-            bail!("psql session request failed: {}", message)
+                bail!("psql session request failed: {}", message)
+            }
        }
    }
 }
--- a/proxy/src/proxy.rs
+++ b/proxy/src/proxy.rs
@@ -57,7 +57,7 @@ pub fn proxy_conn_main(
 ) -> anyhow::Result<()> {
    let mut conn = ProxyConnection {
        state,
-        cplane: CPlaneApi::new(&state.conf.auth_endpoint),
+        cplane: CPlaneApi::new(&state.conf.cplane_address),
        user: "".into(),
        database: "".into(),
        pgb: PostgresBackend::new(
@@ -80,8 +80,6 @@ pub fn proxy_conn_main(
        conn.handle_new_user()?
    };

-    // XXX: move that inside handle_new_user/handle_existing_user to be able to
-    // report wrong connection error.
    proxy_pass(conn.pgb, db_info)
 }

@@ -174,30 +172,21 @@ impl ProxyConnection {
                .split_last()
                .ok_or_else(|| anyhow::Error::msg("unexpected password message"))?;

-            match self.cplane.authenticate_proxy_request(
-                self.user.as_str(),
-                md5_response,
-                &self.md5_salt,
-            ) {
-                Err(e) => {
-                    self.pgb
-                        .write_message(&BeMessage::ErrorResponse(format!("{}", e)))?;
-
-                    bail!("auth failed: {}", e);
-                }
-                Ok(conn_info) => {
-                    self.pgb
-                        .write_message_noflush(&BeMessage::AuthenticationOk)?;
-                    self.pgb
-                        .write_message_noflush(&BeMessage::ParameterStatus)?;
-                    self.pgb.write_message(&BeMessage::ReadyForQuery)?;
-
-                    Ok(conn_info)
-                }
+            if let Err(e) = self.check_auth_md5(md5_response) {
+                self.pgb
+                    .write_message(&BeMessage::ErrorResponse(format!("{}", e)))?;
+                bail!("auth failed: {}", e);
+            } else {
+                self.pgb
+                    .write_message_noflush(&BeMessage::AuthenticationOk)?;
+                self.pgb
+                    .write_message_noflush(&BeMessage::ParameterStatus)?;
+                self.pgb.write_message(&BeMessage::ReadyForQuery)?;
            }
-        } else {
-            bail!("protocol violation");
        }
+
+        // ok, we are authorized
+        self.cplane.get_database_uri(&self.user, &self.database)
    }

    fn handle_new_user(&mut self) -> anyhow::Result<DatabaseInfo> {
@@ -243,6 +232,12 @@ databases without opening the browser.

        Ok(dbinfo)
    }
+
+    fn check_auth_md5(&self, md5_response: &[u8]) -> anyhow::Result<()> {
+        assert!(self.is_existing_user());
+        self.cplane
+            .check_auth(self.user.as_str(), md5_response, &self.md5_salt)
+    }
 }

 /// Create a TCP connection to a postgres database, authenticate with it, and receive the ReadyForQuery message
@@ -278,9 +273,7 @@ fn proxy(

 /// Proxy a client connection to a postgres database
 fn proxy_pass(pgb: PostgresBackend, db_info: DatabaseInfo) -> anyhow::Result<()> {
-    let runtime = tokio::runtime::Builder::new_current_thread()
-        .enable_all()
-        .build()?;
+    let runtime = tokio::runtime::Builder::new_current_thread().build()?;
    let db_stream = runtime.block_on(connect_to_db(db_info))?;
    let db_stream = db_stream.into_std()?;
    db_stream.set_nonblocking(false)?;
--- a/run_clippy.sh
+++ b/run_clippy.sh
@@ -8,8 +8,4 @@
 # warnings and errors right in the editor.
 # In vscode, this setting is Rust-analyzer>Check On Save:Command

-
-# * `-A unknown_lints` – do not warn about unknown lint suppressions
-#                        that people with newer toolchains might use
-# * `-D warnings`      - fail on any warnings (`cargo` returns non-zero exit status)
-cargo clippy "${@:2}" --all-targets --all-features --all --tests -- -A unknown_lints -D warnings
+cargo clippy "${@:2}" -- -A clippy::new_without_default -A clippy::manual_range_contains -A clippy::comparison_chain
--- a/test_runner/Pipfile
+++ b/test_runner/Pipfile
@@ -9,8 +9,6 @@ psycopg2 = "*"
 typing-extensions = "*"
 pyjwt = {extras = ["crypto"], version = "*"}
 requests = "*"
-pytest-xdist = "*"
-asyncpg = "*"

 [dev-packages]
 yapf = "*"
--- a/test_runner/Pipfile.lock
+++ b/test_runner/Pipfile.lock
@@ -1,7 +1,7 @@
 {
    "_meta": {
        "hash": {
-            "sha256": "3cdc048691824d0b93912b6b78a0aa01dc98f278212c1badb0cc2edbd2103c3a"
+            "sha256": "b666740289d9c82797e5c39b2a7f0074c865c9183ee878ce4fa5cda7928506ea"
        },
        "pipfile-spec": 6,
        "requires": {
@@ -16,25 +16,6 @@
        ]
    },
    "default": {
-        "asyncpg": {
-            "hashes": [
-                "sha256:129d501f3d30616afd51eb8d3142ef51ba05374256bd5834cec3ef4956a9b317",
-                "sha256:29ef6ae0a617fc13cc2ac5dc8e9b367bb83cba220614b437af9b67766f4b6b20",
-                "sha256:41704c561d354bef01353835a7846e5606faabbeb846214dfcf666cf53319f18",
-                "sha256:556b0e92e2b75dc028b3c4bc9bd5162ddf0053b856437cf1f04c97f9c6837d03",
-                "sha256:8ff5073d4b654e34bd5eaadc01dc4d68b8a9609084d835acd364cd934190a08d",
-                "sha256:a458fc69051fbb67d995fdda46d75a012b5d6200f91e17d23d4751482640ed4c",
-                "sha256:a7095890c96ba36f9f668eb552bb020dddb44f8e73e932f8573efc613ee83843",
-                "sha256:a738f4807c853623d3f93f0fea11f61be6b0e5ca16ea8aeb42c2c7ee742aa853",
-                "sha256:c4fc0205fe4ddd5aeb3dfdc0f7bafd43411181e1f5650189608e5971cceacff1",
-                "sha256:dd2fa063c3344823487d9ddccb40802f02622ddf8bf8a6cc53885ee7a2c1c0c6",
-                "sha256:ddffcb85227bf39cd1bedd4603e0082b243cf3b14ced64dce506a15b05232b83",
-                "sha256:e36c6806883786b19551bb70a4882561f31135dc8105a59662e0376cf5b2cbc5",
-                "sha256:eed43abc6ccf1dc02e0d0efc06ce46a411362f3358847c6b0ec9a43426f91ece"
-            ],
-            "index": "pypi",
-            "version": "==0.24.0"
-        },
        "attrs": {
            "hashes": [
                "sha256:149e90d6d8ac20db7a955ad60cf0e6881a3f20d37096140088356da6c716b0b1",
@@ -102,43 +83,30 @@
        },
        "charset-normalizer": {
            "hashes": [
-                "sha256:5d209c0a931f215cee683b6445e2d77677e7e75e159f78def0db09d68fafcaa6",
-                "sha256:5ec46d183433dcbd0ab716f2d7f29d8dee50505b3fdb40c6b985c7c4f5a3591f"
+                "sha256:0c8911edd15d19223366a194a513099a302055a962bca2cec0f54b8b63175d8b",
+                "sha256:f23667ebe1084be45f6ae0538e4a5a865206544097e4e8bbcacf42cd02a348f3"
            ],
            "markers": "python_version >= '3'",
-            "version": "==2.0.6"
+            "version": "==2.0.4"
        },
        "cryptography": {
            "hashes": [
-                "sha256:0a7dcbcd3f1913f664aca35d47c1331fce738d44ec34b7be8b9d332151b0b01e",
-                "sha256:1eb7bb0df6f6f583dd8e054689def236255161ebbcf62b226454ab9ec663746b",
-                "sha256:21ca464b3a4b8d8e86ba0ee5045e103a1fcfac3b39319727bc0fc58c09c6aff7",
-                "sha256:34dae04a0dce5730d8eb7894eab617d8a70d0c97da76b905de9efb7128ad7085",
-                "sha256:3520667fda779eb788ea00080124875be18f2d8f0848ec00733c0ec3bb8219fc",
-                "sha256:3c4129fc3fdc0fa8e40861b5ac0c673315b3c902bbdc05fc176764815b43dd1d",
-                "sha256:3fa3a7ccf96e826affdf1a0a9432be74dc73423125c8f96a909e3835a5ef194a",
-                "sha256:5b0fbfae7ff7febdb74b574055c7466da334a5371f253732d7e2e7525d570498",
-                "sha256:695104a9223a7239d155d7627ad912953b540929ef97ae0c34c7b8bf30857e89",
-                "sha256:8695456444f277af73a4877db9fc979849cd3ee74c198d04fc0776ebc3db52b9",
-                "sha256:94cc5ed4ceaefcbe5bf38c8fba6a21fc1d365bb8fb826ea1688e3370b2e24a1c",
-                "sha256:94fff993ee9bc1b2440d3b7243d488c6a3d9724cc2b09cdb297f6a886d040ef7",
-                "sha256:9965c46c674ba8cc572bc09a03f4c649292ee73e1b683adb1ce81e82e9a6a0fb",
-                "sha256:a00cf305f07b26c351d8d4e1af84ad7501eca8a342dedf24a7acb0e7b7406e14",
-                "sha256:a305600e7a6b7b855cd798e00278161b681ad6e9b7eca94c721d5f588ab212af",
-                "sha256:cd65b60cfe004790c795cc35f272e41a3df4631e2fb6b35aa7ac6ef2859d554e",
-                "sha256:d2a6e5ef66503da51d2110edf6c403dc6b494cc0082f85db12f54e9c5d4c3ec5",
-                "sha256:d9ec0e67a14f9d1d48dd87a2531009a9b251c02ea42851c060b25c782516ff06",
-                "sha256:f44d141b8c4ea5eb4dbc9b3ad992d45580c1d22bf5e24363f2fbf50c2d7ae8a7"
+                "sha256:0f1212a66329c80d68aeeb39b8a16d54ef57071bf22ff4e521657b27372e327d",
+                "sha256:1e056c28420c072c5e3cb36e2b23ee55e260cb04eee08f702e0edfec3fb51959",
+                "sha256:240f5c21aef0b73f40bb9f78d2caff73186700bf1bc6b94285699aff98cc16c6",
+                "sha256:26965837447f9c82f1855e0bc8bc4fb910240b6e0d16a664bb722df3b5b06873",
+                "sha256:37340614f8a5d2fb9aeea67fd159bfe4f5f4ed535b1090ce8ec428b2f15a11f2",
+                "sha256:3d10de8116d25649631977cb37da6cbdd2d6fa0e0281d014a5b7d337255ca713",
+                "sha256:3d8427734c781ea5f1b41d6589c293089704d4759e34597dce91014ac125aad1",
+                "sha256:7ec5d3b029f5fa2b179325908b9cd93db28ab7b85bb6c1db56b10e0b54235177",
+                "sha256:8e56e16617872b0957d1c9742a3f94b43533447fd78321514abbe7db216aa250",
+                "sha256:b01fd6f2737816cb1e08ed4807ae194404790eac7ad030b34f2ce72b332f5586",
+                "sha256:bf40af59ca2465b24e54f671b2de2c59257ddc4f7e5706dbd6930e26823668d3",
+                "sha256:de4e5f7f68220d92b7637fc99847475b59154b7a1b3868fb7385337af54ac9ca",
+                "sha256:eb8cc2afe8b05acbd84a43905832ec78e7b3873fb124ca190f574dca7389a87d",
+                "sha256:ee77aa129f481be46f8d92a1a7db57269a2f23052d5f2433b4621bb457081cc9"
            ],
-            "version": "==3.4.8"
-        },
-        "execnet": {
-            "hashes": [
-                "sha256:8f694f3ba9cc92cab508b152dcfe322153975c29bda272e2fd7f3f00f36e47c5",
-                "sha256:a295f7cc774947aac58dde7fdc85f4aa00c42adf5d8f5468fc630c1acf30a142"
-            ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
-            "version": "==1.9.0"
+            "version": "==3.4.7"
        },
        "idna": {
            "hashes": [
@@ -165,11 +133,11 @@
        },
        "pluggy": {
            "hashes": [
-                "sha256:4224373bacce55f955a878bf9cfa763c1e360858e330072059e10bad68531159",
-                "sha256:74134bbf457f031a36d68416e1509f34bd5ccc019f0bcc952c7b909d06b37bd3"
+                "sha256:15b2acde666561e1298d71b523007ed7364de07029219b604cf808bfa1c765b0",
+                "sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"
            ],
-            "markers": "python_version >= '3.6'",
-            "version": "==1.0.0"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==0.13.1"
        },
        "psycopg2": {
            "hashes": [
@@ -223,27 +191,11 @@
        },
        "pytest": {
            "hashes": [
-                "sha256:131b36680866a76e6781d13f101efb86cf674ebb9762eb70d3082b6f29889e89",
-                "sha256:7310f8d27bc79ced999e760ca304d69f6ba6c6649c0b60fb0e04a4a77cacc134"
+                "sha256:50bcad0a0b9c5a72c8e4e7c9855a3ad496ca6a881a3641b4260605450772c54b",
+                "sha256:91ef2131a9bd6be8f76f1f08eac5c5317221d6ad1e143ae03894b862e8976890"
            ],
            "index": "pypi",
-            "version": "==6.2.5"
-        },
-        "pytest-forked": {
-            "hashes": [
-                "sha256:6aa9ac7e00ad1a539c41bec6d21011332de671e938c7637378ec9710204e37ca",
-                "sha256:dc4147784048e70ef5d437951728825a131b81714b398d5d52f17c7c144d8815"
-            ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
-            "version": "==1.3.0"
-        },
-        "pytest-xdist": {
-            "hashes": [
-                "sha256:7b61ebb46997a0820a263553179d6d1e25a8c50d8a8620cd1aa1e20e3be99168",
-                "sha256:89b330316f7fc475f999c81b577c2b926c9569f3d397ae432c0c2e2496d61ff9"
-            ],
-            "index": "pypi",
-            "version": "==2.4.0"
+            "version": "==6.2.4"
        },
        "requests": {
            "hashes": [
@@ -263,12 +215,12 @@
        },
        "typing-extensions": {
            "hashes": [
-                "sha256:49f75d16ff11f1cd258e1b988ccff82a3ca5570217d7ad8c5f48205dd99a677e",
-                "sha256:d8226d10bc02a29bcc81df19a26e56a9647f8b0a6d4a83924139f4a8b01f17b7",
-                "sha256:f1d25edafde516b146ecd0613dabcc61409817af4766fbbcfb8d1ad4ec441a34"
+                "sha256:0ac0f89795dd19de6b97debb0c6af1c70987fd80a2d62d1958f7e56fcc31b497",
+                "sha256:50b6f157849174217d0656f99dc82fe932884fb250826c18350e159ec6cdf342",
+                "sha256:779383f6086d90c99ae41cf0ff39aac8a7937a9283ce0a414e5dd782f4c94a84"
            ],
            "index": "pypi",
-            "version": "==3.10.0.2"
+            "version": "==3.10.0.0"
        },
        "urllib3": {
            "hashes": [
@@ -357,12 +309,12 @@
        },
        "typing-extensions": {
            "hashes": [
-                "sha256:49f75d16ff11f1cd258e1b988ccff82a3ca5570217d7ad8c5f48205dd99a677e",
-                "sha256:d8226d10bc02a29bcc81df19a26e56a9647f8b0a6d4a83924139f4a8b01f17b7",
-                "sha256:f1d25edafde516b146ecd0613dabcc61409817af4766fbbcfb8d1ad4ec441a34"
+                "sha256:0ac0f89795dd19de6b97debb0c6af1c70987fd80a2d62d1958f7e56fcc31b497",
+                "sha256:50b6f157849174217d0656f99dc82fe932884fb250826c18350e159ec6cdf342",
+                "sha256:779383f6086d90c99ae41cf0ff39aac8a7937a9283ce0a414e5dd782f4c94a84"
            ],
            "index": "pypi",
-            "version": "==3.10.0.2"
+            "version": "==3.10.0.0"
        },
        "yapf": {
            "hashes": [
--- a/test_runner/batch_others/test_auth.py
+++ b/test_runner/batch_others/test_auth.py
@@ -1,15 +1,11 @@

 from contextlib import closing
-from typing import Iterator
 from uuid import uuid4
 import psycopg2
-from fixtures.zenith_fixtures import PortDistributor, Postgres, ZenithCli, ZenithPageserver, PgBin
+from fixtures.zenith_fixtures import Postgres, ZenithCli, ZenithPageserver, PgBin
 import pytest


-pytest_plugins = ("fixtures.zenith_fixtures")
-
-
 def test_pageserver_auth(pageserver_auth_enabled: ZenithPageserver):
    ps = pageserver_auth_enabled

@@ -46,8 +42,7 @@ def test_compute_auth_to_pageserver(
    pageserver_auth_enabled: ZenithPageserver,
    repo_dir: str,
    with_wal_acceptors: bool,
-    pg_bin: PgBin,
-    port_distributor: PortDistributor,
+    pg_bin: PgBin
 ):
    ps = pageserver_auth_enabled
    # since we are in progress of refactoring protocols between compute safekeeper and page server
@@ -64,7 +59,7 @@ def test_compute_auth_to_pageserver(
        repo_dir=repo_dir,
        pg_bin=pg_bin,
        tenant_id=ps.initial_tenant,
-        port=port_distributor.get_port(),
+        port=55432, # FIXME port distribution is hardcoded in tests and in cli
    ).create_start(
        branch,
        wal_acceptors=wa_factory.get_connstrs() if with_wal_acceptors else None,
--- a/test_runner/batch_others/test_branch_behind.py
+++ b/test_runner/batch_others/test_branch_behind.py
@@ -1,9 +1,5 @@
-import subprocess
 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -16,7 +12,7 @@ def test_branch_behind(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    zenith_cli.run(["branch", "test_branch_behind", "empty"])

    pgmain = postgres.create_start('test_branch_behind')
-    log.info("postgres is running on 'test_branch_behind' branch")
+    print("postgres is running on 'test_branch_behind' branch")

    main_pg_conn = pgmain.connect()
    main_cur = main_pg_conn.cursor()
@@ -30,7 +26,7 @@ def test_branch_behind(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    ''')
    main_cur.execute('SELECT pg_current_wal_insert_lsn()')
    lsn_a = main_cur.fetchone()[0]
-    log.info(f'LSN after 100 rows: {lsn_a}')
+    print('LSN after 100 rows: ' + lsn_a)

    # Insert some more rows. (This generates enough WAL to fill a few segments.)
    main_cur.execute('''
@@ -40,7 +36,7 @@ def test_branch_behind(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    ''')
    main_cur.execute('SELECT pg_current_wal_insert_lsn()')
    lsn_b = main_cur.fetchone()[0]
-    log.info(f'LSN after 100100 rows: {lsn_b}')
+    print('LSN after 100100 rows: ' + lsn_b)

    # Branch at the point where only 100 rows were inserted
    zenith_cli.run(["branch", "test_branch_behind_hundred", "test_branch_behind@" + lsn_a])
@@ -55,7 +51,7 @@ def test_branch_behind(zenith_cli, pageserver: ZenithPageserver, postgres: Postg

    main_cur.execute('SELECT pg_current_wal_insert_lsn()')
    lsn_c = main_cur.fetchone()[0]
-    log.info(f'LSN after 200100 rows: {lsn_c}')
+    print('LSN after 200100 rows: ' + lsn_c)

    # Branch at the point where only 200 rows were inserted
    zenith_cli.run(["branch", "test_branch_behind_more", "test_branch_behind@" + lsn_b])
@@ -78,18 +74,3 @@ def test_branch_behind(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    # All the rows are visible on the main branch
    main_cur.execute('SELECT count(*) FROM foo')
    assert main_cur.fetchone() == (200100, )
-
-    # Check bad lsn's for branching
-
-    # branch at segment boundary
-    zenith_cli.run(["branch", "test_branch_segment_boundary", "test_branch_behind@0/3000000"])
-    pg = postgres.create_start("test_branch_segment_boundary")
-    cur = pg.connect().cursor()
-    cur.execute('SELECT 1')
-    assert cur.fetchone() == (1, )
-
-    # branch at pre-initdb lsn
-    try:
-        zenith_cli.run(["branch", "test_branch_preinitdb", "test_branch_behind@0/42"])
-    except subprocess.CalledProcessError:
-        log.info("Branch creation with pre-initdb LSN failed (as expected)")
--- a/test_runner/batch_others/test_clog_truncate.py
+++ b/test_runner/batch_others/test_clog_truncate.py
@@ -5,10 +5,6 @@ from contextlib import closing

 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")


@@ -28,7 +24,7 @@ def test_clog_truncate(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    ]

    pg = postgres.create_start('test_clog_truncate', config_lines=config)
-    log.info('postgres is running on test_clog_truncate branch')
+    print('postgres is running on test_clog_truncate branch')

    # Install extension containing function needed for test
    pg.safe_psql('CREATE EXTENSION zenith_test_utils')
@@ -37,22 +33,22 @@ def test_clog_truncate(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
            cur.execute('select test_consume_xids(1000*1000*10);')
-            log.info('xids consumed')
+            print('xids consumed')

            # call a checkpoint to trigger TruncateSubtrans
            cur.execute('CHECKPOINT;')

            # ensure WAL flush
            cur.execute('select txid_current()')
-            log.info(cur.fetchone())
+            print(cur.fetchone())

    # wait for autovacuum to truncate the pg_xact
    # XXX Is it worth to add a timeout here?
    pg_xact_0000_path = os.path.join(pg.pg_xact_dir_path(), '0000')
-    log.info(f"pg_xact_0000_path = {pg_xact_0000_path}")
+    print("pg_xact_0000_path = " + pg_xact_0000_path)

    while os.path.isfile(pg_xact_0000_path):
-        log.info(f"file exists. wait for truncation. " "pg_xact_0000_path = {pg_xact_0000_path}")
+        print("file exists. wait for truncation. " "pg_xact_0000_path = " + pg_xact_0000_path)
        time.sleep(5)

    # checkpoint to advance latest lsn
@@ -63,14 +59,14 @@ def test_clog_truncate(zenith_cli, pageserver: ZenithPageserver, postgres: Postg
            lsn_after_truncation = cur.fetchone()[0]

    # create new branch after clog truncation and start a compute node on it
-    log.info(f'create branch at lsn_after_truncation {lsn_after_truncation}')
+    print('create branch at lsn_after_truncation ' + lsn_after_truncation)
    zenith_cli.run(
        ["branch", "test_clog_truncate_new", "test_clog_truncate@" + lsn_after_truncation])

    pg2 = postgres.create_start('test_clog_truncate_new')
-    log.info('postgres is running on test_clog_truncate_new branch')
+    print('postgres is running on test_clog_truncate_new branch')

    # check that new node doesn't contain truncated segment
    pg_xact_0000_path_new = os.path.join(pg2.pg_xact_dir_path(), '0000')
-    log.info("pg_xact_0000_path_new = " + pg_xact_0000_path_new)
+    print("pg_xact_0000_path_new = " + pg_xact_0000_path_new)
    assert os.path.isfile(pg_xact_0000_path_new) is False
--- a/test_runner/batch_others/test_config.py
+++ b/test_runner/batch_others/test_config.py
@@ -2,10 +2,6 @@ from contextlib import closing

 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")


@@ -18,7 +14,7 @@ def test_config(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFact

    # change config
    pg = postgres.create_start('test_config', config_lines=['log_min_messages=debug1'])
-    log.info('postgres is running on test_config branch')
+    print('postgres is running on test_config branch')

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
--- a/test_runner/batch_others/test_createdropdb.py
+++ b/test_runner/batch_others/test_createdropdb.py
@@ -2,11 +2,7 @@ import os
 import pathlib

 from contextlib import closing
-from fixtures.zenith_fixtures import ZenithPageserver, PostgresFactory, ZenithCli, check_restored_datadir_content
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
+from fixtures.zenith_fixtures import ZenithPageserver, PostgresFactory, ZenithCli

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -23,7 +19,7 @@ def test_createdb(
    zenith_cli.run(["branch", "test_createdb", "empty"])

    pg = postgres.create_start('test_createdb')
-    log.info("postgres is running on 'test_createdb' branch")
+    print("postgres is running on 'test_createdb' branch")

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
@@ -52,12 +48,11 @@ def test_dropdb(
    pageserver: ZenithPageserver,
    postgres: PostgresFactory,
    pg_bin,
-    test_output_dir
 ):
    zenith_cli.run(["branch", "test_dropdb", "empty"])

    pg = postgres.create_start('test_dropdb')
-    log.info("postgres is running on 'test_dropdb' branch")
+    print("postgres is running on 'test_dropdb' branch")

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
@@ -74,8 +69,6 @@ def test_dropdb(
        with conn.cursor() as cur:
            cur.execute('DROP DATABASE foodb')

-            cur.execute('CHECKPOINT')
-
            cur.execute('SELECT pg_current_wal_insert_lsn()')
            lsn_after_drop = cur.fetchone()[0]

@@ -92,15 +85,12 @@ def test_dropdb(

    # Test that database subdir exists on the branch before drop
    dbpath = pathlib.Path(pg_before.pgdata_dir) / 'base' / str(dboid)
-    log.info(dbpath)
+    print(dbpath)

    assert os.path.isdir(dbpath) == True

    # Test that database subdir doesn't exist on the branch after drop
    dbpath = pathlib.Path(pg_after.pgdata_dir) / 'base' / str(dboid)
-    log.info(dbpath)
+    print(dbpath)

    assert os.path.isdir(dbpath) == False
-
-    # Check that we restore the content of the datadir correctly
-    check_restored_datadir_content(zenith_cli, test_output_dir, pg, pageserver.service_port.pg)
--- a/test_runner/batch_others/test_createuser.py
+++ b/test_runner/batch_others/test_createuser.py
@@ -2,10 +2,6 @@ from contextlib import closing

 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")


@@ -16,7 +12,7 @@ def test_createuser(zenith_cli, pageserver: ZenithPageserver, postgres: Postgres
    zenith_cli.run(["branch", "test_createuser", "empty"])

    pg = postgres.create_start('test_createuser')
-    log.info("postgres is running on 'test_createuser' branch")
+    print("postgres is running on 'test_createuser' branch")

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
--- a/test_runner/batch_others/test_multixact.py
+++ b/test_runner/batch_others/test_multixact.py
@@ -1,8 +1,4 @@
-from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver, check_restored_datadir_content
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
+from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -13,13 +9,12 @@ pytest_plugins = ("fixtures.zenith_fixtures")
 # it only checks next_multixact_id field in restored pg_control,
 # since we don't have functions to check multixact internals.
 #
-def test_multixact(pageserver: ZenithPageserver, postgres: PostgresFactory,
-                    pg_bin, zenith_cli, base_dir, test_output_dir):
+def test_multixact(pageserver: ZenithPageserver, postgres: PostgresFactory, pg_bin, zenith_cli, base_dir):
    # Create a branch for us
    zenith_cli.run(["branch", "test_multixact", "empty"])
    pg = postgres.create_start('test_multixact')

-    log.info("postgres is running on 'test_multixact' branch")
+    print("postgres is running on 'test_multixact' branch")
    pg_conn = pg.connect()
    cur = pg_conn.cursor()

@@ -59,7 +54,7 @@ def test_multixact(pageserver: ZenithPageserver, postgres: PostgresFactory,
    zenith_cli.run(["branch", "test_multixact_new", "test_multixact@" + lsn])
    pg_new = postgres.create_start('test_multixact_new')

-    log.info("postgres is running on 'test_multixact_new' branch")
+    print("postgres is running on 'test_multixact_new' branch")
    pg_new_conn = pg_new.connect()
    cur_new = pg_new_conn.cursor()

@@ -68,6 +63,3 @@ def test_multixact(pageserver: ZenithPageserver, postgres: PostgresFactory,

    # Check that we restored pg_controlfile correctly
    assert next_multixact_id_new == next_multixact_id
-
-    # Check that we restore the content of the datadir correctly
-    check_restored_datadir_content(zenith_cli, test_output_dir, pg_new, pageserver.service_port.pg)
--- a/test_runner/batch_others/test_old_request_lsn.py
+++ b/test_runner/batch_others/test_old_request_lsn.py
@@ -1,69 +0,0 @@
-from contextlib import closing
-
-from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
-pytest_plugins = ("fixtures.zenith_fixtures")
-
-#
-# Test where Postgres generates a lot of WAL, and it's garbage collected away, but
-# no pages are evicted so that Postgres uses an old LSN in a GetPage request.
-# We had a bug where the page server failed to find the page version because it
-# thought it was already garbage collected away, because the LSN in the GetPage
-# request was very old and the WAL from that time was indeed already removed.
-# In reality, the LSN on a GetPage request coming from a primary server is
-# just a hint that the page hasn't been modified since that LSN, and the page
-# server should return the latest page version regardless of the LSN.
-#
-def test_old_request_lsn(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFactory, pg_bin):
-    # Create a branch for us
-    zenith_cli.run(["branch", "test_old_request_lsn", "empty"])
-    pg = postgres.create_start('test_old_request_lsn')
-    log.info('postgres is running on test_old_request_lsn branch')
-
-    pg_conn = pg.connect()
-    cur = pg_conn.cursor()
-
-    # Get the timeline ID of our branch. We need it for the 'do_gc' command
-    cur.execute("SHOW zenith.zenith_timeline")
-    timeline = cur.fetchone()[0]
-
-    psconn = pageserver.connect()
-    pscur = psconn.cursor()
-
-    # Create table, and insert some rows. Make it big enough that it doesn't fit in
-    # shared_buffers.
-    cur.execute('CREATE TABLE foo (id int4 PRIMARY KEY, val int, t text)')
-    cur.execute('''
-        INSERT INTO foo
-            SELECT g, 1, 'long string to consume some space' || g
-            FROM generate_series(1, 100000) g
-    ''')
-
-    # Verify that the table is larger than shared_buffers, so that the SELECT below
-    # will cause GetPage requests.
-    cur.execute('''
-        select setting::int * pg_size_bytes(unit) as shared_buffers, pg_relation_size('foo') as tbl_ize
-        from pg_settings where name = 'shared_buffers'
-    ''')
-    row = cur.fetchone()
-    log.info(f'shared_buffers is {row[0]}, table size {row[1]}');
-    assert int(row[0]) < int(row[1])
-
-    cur.execute('VACUUM foo');
-
-    # Make a lot of updates on a single row, generating a lot of WAL. Trigger
-    # garbage collections so that the page server will remove old page versions.
-    for i in range(10):
-        pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
-        for j in range(100):
-            cur.execute('UPDATE foo SET val = val + 1 WHERE id = 1;');
-
-    # All (or at least most of) the updates should've been on the same page, so
-    # that we haven't had to evict any dirty pages for a long time. Now run
-    # a query that sends GetPage@LSN requests with the old LSN.
-    cur.execute("SELECT COUNT(*), SUM(val) FROM foo");
-    assert cur.fetchone() == (100000, 101000)
--- a/test_runner/batch_others/test_pageserver_restart.py
+++ b/test_runner/batch_others/test_pageserver_restart.py
@@ -6,10 +6,6 @@ from contextlib import closing
 from multiprocessing import Process, Value
 from fixtures.zenith_fixtures import WalAcceptorFactory, ZenithPageserver, PostgresFactory

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")

 # Check that dead minority doesn't prevent the commits: execute insert n_inserts
@@ -44,7 +40,7 @@ def test_pageserver_restart(zenith_cli, pageserver: ZenithPageserver, postgres:
        from pg_settings where name = 'shared_buffers'
    ''')
    row = cur.fetchone()
-    log.info(f"shared_buffers is {row[0]}, table size {row[1]}");
+    print("shared_buffers is {}, table size {}", row[0], row[1]);
    assert int(row[0]) < int(row[1])

    # Stop and restart pageserver. This is a more or less graceful shutdown, although
--- a/test_runner/batch_others/test_pgbench.py
+++ b/test_runner/batch_others/test_pgbench.py
@@ -1,9 +1,5 @@
 from fixtures.zenith_fixtures import PostgresFactory

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")


@@ -12,7 +8,7 @@ def test_pgbench(postgres: PostgresFactory, pg_bin, zenith_cli):
    zenith_cli.run(["branch", "test_pgbench", "empty"])

    pg = postgres.create_start('test_pgbench')
-    log.info("postgres is running on 'test_pgbench' branch")
+    print("postgres is running on 'test_pgbench' branch")

    connstr = pg.connstr()

--- a/test_runner/batch_others/test_restart_compute.py
+++ b/test_runner/batch_others/test_restart_compute.py
@@ -3,10 +3,6 @@ import pytest
 from contextlib import closing
 from fixtures.zenith_fixtures import ZenithPageserver, PostgresFactory

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")


@@ -34,7 +30,7 @@ def test_restart_compute(

    pg = postgres.create_start('test_restart_compute',
                               wal_acceptors=wal_acceptor_connstrs)
-    log.info("postgres is running on 'test_restart_compute' branch")
+    print("postgres is running on 'test_restart_compute' branch")

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
@@ -43,7 +39,7 @@ def test_restart_compute(
            cur.execute('SELECT sum(key) FROM t')
            r = cur.fetchone()
            assert r == (5000050000, )
-            log.info(f"res = {r}")
+            print("res = ", r)

    # Remove data directory and restart
    pg.stop_and_destroy().create_start('test_restart_compute',
@@ -56,7 +52,7 @@ def test_restart_compute(
            cur.execute('SELECT sum(key) FROM t')
            r = cur.fetchone()
            assert r == (5000050000, )
-            log.info(f"res = {r}")
+            print("res = ", r)

            # Insert another row
            cur.execute("INSERT INTO t VALUES (100001, 'payload2')")
@@ -64,7 +60,7 @@ def test_restart_compute(

            r = cur.fetchone()
            assert r == (100001, )
-            log.info(f"res = {r}")
+            print("res = ", r)

    # Again remove data directory and restart
    pg.stop_and_destroy().create_start('test_restart_compute',
@@ -79,7 +75,7 @@ def test_restart_compute(

            r = cur.fetchone()
            assert r == (100001, )
-            log.info(f"res = {r}")
+            print("res = ", r)

    # And again remove data directory and restart
    pg.stop_and_destroy().create_start('test_restart_compute',
@@ -92,4 +88,4 @@ def test_restart_compute(

            r = cur.fetchone()
            assert r == (100001, )
-            log.info(f"res = {r}")
+            print("res = ", r)
--- a/test_runner/batch_others/test_snapfiles_gc.py
+++ b/test_runner/batch_others/test_snapfiles_gc.py
@@ -2,27 +2,23 @@ from contextlib import closing
 import psycopg2.extras
 import time;

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")

 def print_gc_result(row):
-    log.info("GC duration {elapsed} ms".format_map(row));
-    log.info("  REL    total: {layer_relfiles_total}, needed_by_cutoff {layer_relfiles_needed_by_cutoff}, needed_by_branches: {layer_relfiles_needed_by_branches}, not_updated: {layer_relfiles_not_updated}, needed_as_tombstone {layer_relfiles_needed_as_tombstone}, removed: {layer_relfiles_removed}, dropped: {layer_relfiles_dropped}".format_map(row))
-    log.info("  NONREL total: {layer_nonrelfiles_total}, needed_by_cutoff {layer_nonrelfiles_needed_by_cutoff}, needed_by_branches: {layer_nonrelfiles_needed_by_branches}, not_updated: {layer_nonrelfiles_not_updated}, needed_as_tombstone {layer_nonrelfiles_needed_as_tombstone}, removed: {layer_nonrelfiles_removed}, dropped: {layer_nonrelfiles_dropped}".format_map(row))
+    print("GC duration {elapsed} ms".format_map(row));
+    print("  REL    total: {snapshot_relfiles_total}, needed_by_cutoff {snapshot_relfiles_needed_by_cutoff}, needed_by_branches: {snapshot_relfiles_needed_by_branches}, not_updated: {snapshot_relfiles_not_updated}, removed: {snapshot_relfiles_removed}, dropped: {snapshot_relfiles_dropped}".format_map(row))
+    print("  NONREL total: {snapshot_nonrelfiles_total}, needed_by_cutoff {snapshot_nonrelfiles_needed_by_cutoff}, needed_by_branches: {snapshot_nonrelfiles_needed_by_branches}, not_updated: {snapshot_nonrelfiles_not_updated}, removed: {snapshot_nonrelfiles_removed}, dropped: {snapshot_nonrelfiles_dropped}".format_map(row))


 #
-# Test Garbage Collection of old layer files
+# Test Garbage Collection of old snapshot files
 #
 # This test is pretty tightly coupled with the current implementation of layered
 # storage, in layered_repository.rs.
 #
-def test_layerfiles_gc(zenith_cli, pageserver, postgres, pg_bin):
-    zenith_cli.run(["branch", "test_layerfiles_gc", "empty"])
-    pg = postgres.create_start('test_layerfiles_gc')
+def test_snapfiles_gc(zenith_cli, pageserver, postgres, pg_bin):
+    zenith_cli.run(["branch", "test_snapfiles_gc", "empty"])
+    pg = postgres.create_start('test_snapfiles_gc')

    with closing(pg.connect()) as conn:
        with conn.cursor() as cur:
@@ -39,7 +35,7 @@ def test_layerfiles_gc(zenith_cli, pageserver, postgres, pg_bin):

                    cur.execute("select relfilenode from pg_class where oid = 'foo'::regclass");
                    row = cur.fetchone();
-                    log.info(f"relfilenode is {row[0]}");
+                    print("relfilenode is {}", row[0]);

                    # Run GC, to clear out any garbage left behind in the catalogs by
                    # the CREATE TABLE command. We want to have a clean slate with no garbage
@@ -54,84 +50,75 @@ def test_layerfiles_gc(zenith_cli, pageserver, postgres, pg_bin):
                    # update to confuse our numbers either.
                    cur.execute("DELETE FROM foo")

-                    log.info("Running GC before test")
+                    print("Running GC before test")
                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);
                    # remember the number of files
-                    layer_relfiles_remain = row['layer_relfiles_total'] - row['layer_relfiles_removed']
-                    assert layer_relfiles_remain > 0
+                    snapshot_relfiles_remain = row['snapshot_relfiles_total'] - row['snapshot_relfiles_removed']
+                    assert snapshot_relfiles_remain > 0

-                    # Insert a row and run GC. Checkpoint should freeze the layer
-                    # so that there is only the most recent image layer left for the rel,
-                    # removing the old image and delta layer.
-                    log.info("Inserting one row and running GC")
+                    # Insert a row.
+                    print("Inserting one row and running GC")
                    cur.execute("INSERT INTO foo VALUES (1)")
                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);
-                    assert row['layer_relfiles_total'] == layer_relfiles_remain + 2
-                    assert row['layer_relfiles_removed'] == 2
-                    assert row['layer_relfiles_dropped'] == 0
+                    assert row['snapshot_relfiles_total'] == snapshot_relfiles_remain + 1
+                    assert row['snapshot_relfiles_removed'] == 1
+                    assert row['snapshot_relfiles_dropped'] == 0

                    # Insert two more rows and run GC.
-                    # This should create new image and delta layer file with the new contents, and
-                    # then remove the old one image and the just-created delta layer.
-                    log.info("Inserting two more rows and running GC")
+                    # This should create a new snapshot file with the new contents, and
+                    # remove the old one.
+                    print("Inserting two more rows and running GC")
                    cur.execute("INSERT INTO foo VALUES (2)")
                    cur.execute("INSERT INTO foo VALUES (3)")

                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);
-                    assert row['layer_relfiles_total'] == layer_relfiles_remain + 2
-                    assert row['layer_relfiles_removed'] == 2
-                    assert row['layer_relfiles_dropped'] == 0
+                    assert row['snapshot_relfiles_total'] == snapshot_relfiles_remain + 1
+                    assert row['snapshot_relfiles_removed'] == 1
+                    assert row['snapshot_relfiles_dropped'] == 0

-                    # Do it again. Should again create two new layer files and remove old ones.
-                    log.info("Inserting two more rows and running GC")
+                    # Do it again. Should again create a new snapshot file and remove old one.
+                    print("Inserting two more rows and running GC")
                    cur.execute("INSERT INTO foo VALUES (2)")
                    cur.execute("INSERT INTO foo VALUES (3)")

                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);
-                    assert row['layer_relfiles_total'] == layer_relfiles_remain + 2
-                    assert row['layer_relfiles_removed'] == 2
-                    assert row['layer_relfiles_dropped'] == 0
+                    assert row['snapshot_relfiles_total'] == snapshot_relfiles_remain + 1
+                    assert row['snapshot_relfiles_removed'] == 1
+                    assert row['snapshot_relfiles_dropped'] == 0

                    # Run GC again, with no changes in the database. Should not remove anything.
-                    log.info("Run GC again, with nothing to do")
+                    print("Run GC again, with nothing to do")
                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);
-                    assert row['layer_relfiles_total'] == layer_relfiles_remain
-                    assert row['layer_relfiles_removed'] == 0
-                    assert row['layer_relfiles_dropped'] == 0
+                    assert row['snapshot_relfiles_total'] == snapshot_relfiles_remain
+                    assert row['snapshot_relfiles_removed'] == 0
+                    assert row['snapshot_relfiles_dropped'] == 0

                    #
                    # Test DROP TABLE checks that relation data and metadata was deleted by GC from object storage
                    #
-                    log.info("Drop table and run GC again");
+                    print("Drop table and run GC again");
                    cur.execute("DROP TABLE foo")

                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
                    row = pscur.fetchone()
                    print_gc_result(row);

-                    # We still cannot remove the latest layers
-                    # because they serve as tombstones for earlier layers.
-                    assert row['layer_relfiles_dropped'] == 0
                    # Each relation fork is counted separately, hence 3.
-                    assert row['layer_relfiles_needed_as_tombstone'] == 3
+                    assert row['snapshot_relfiles_dropped'] == 3

-                    # The catalog updates also create new layer files of the catalogs, which
+                    # The catalog updates also create new snapshot files of the catalogs, which
                    # are counted as 'removed'
-                    assert row['layer_relfiles_removed'] > 0
-
-                    # TODO Change the test to check actual CG of dropped layers.
-                    # Each relation fork is counted separately, hence 3.
-                    #assert row['layer_relfiles_dropped'] == 3
+                    assert row['snapshot_relfiles_removed'] > 0

                    # TODO: perhaps we should count catalog and user relations separately,
                    # to make this kind of testing more robust
--- a/test_runner/batch_others/test_timeline_size.py
+++ b/test_runner/batch_others/test_timeline_size.py
@@ -1,42 +0,0 @@
-from contextlib import closing
-from uuid import UUID
-import psycopg2.extras
-from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
-def test_timeline_size(
-    zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFactory, pg_bin
-):
-    # Branch at the point where only 100 rows were inserted
-    zenith_cli.run(["branch", "test_timeline_size", "empty"])
-
-    client = pageserver.http_client()
-    res = client.branch_detail(UUID(pageserver.initial_tenant), "test_timeline_size")
-    assert res["current_logical_size"] == res["current_logical_size_non_incremental"]
-
-    pgmain = postgres.create_start("test_timeline_size")
-    log.info("postgres is running on 'test_timeline_size' branch")
-
-    with closing(pgmain.connect()) as conn:
-        with conn.cursor() as cur:
-            cur.execute("SHOW zenith.zenith_timeline")
-
-            # Create table, and insert the first 100 rows
-            cur.execute("CREATE TABLE foo (t text)")
-            cur.execute(
-                """
-                INSERT INTO foo
-                    SELECT 'long string to consume some space' || g
-                    FROM generate_series(1, 10) g
-            """
-            )
-
-            res = client.branch_detail(UUID(pageserver.initial_tenant), "test_timeline_size")
-            assert res["current_logical_size"] == res["current_logical_size_non_incremental"]
-            cur.execute("TRUNCATE foo")
-
-            res = client.branch_detail(UUID(pageserver.initial_tenant), "test_timeline_size")
-            assert res["current_logical_size"] == res["current_logical_size_non_incremental"]
--- a/test_runner/batch_others/test_twophase.py
+++ b/test_runner/batch_others/test_twophase.py
@@ -2,9 +2,6 @@ import os

 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver, PgBin

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -16,7 +13,7 @@ def test_twophase(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFa
    zenith_cli.run(["branch", "test_twophase", "empty"])

    pg = postgres.create_start('test_twophase', config_lines=['max_prepared_transactions=5'])
-    log.info("postgres is running on 'test_twophase' branch")
+    print("postgres is running on 'test_twophase' branch")

    conn = pg.connect()
    cur = conn.cursor()
@@ -48,7 +45,7 @@ def test_twophase(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFa
    cur.execute('CHECKPOINT')

    twophase_files = os.listdir(pg.pg_twophase_dir_path())
-    log.info(twophase_files)
+    print(twophase_files)
    assert len(twophase_files) == 4

    cur.execute("COMMIT PREPARED 'insert_three'")
@@ -56,23 +53,25 @@ def test_twophase(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFa
    cur.execute('CHECKPOINT')

    twophase_files = os.listdir(pg.pg_twophase_dir_path())
-    log.info(twophase_files)
+    print(twophase_files)
    assert len(twophase_files) == 2

    # Create a branch with the transaction in prepared state
    zenith_cli.run(["branch", "test_twophase_prepared", "test_twophase"])

-    # Start compute on the new branch
-    pg2 = postgres.create_start(
+    # Create compute node, but don't start.
+    # We want to observe pgdata before postgres starts
+    pg2 = postgres.create(
        'test_twophase_prepared',
        config_lines=['max_prepared_transactions=5'],
    )

    # Check that we restored only needed twophase files
    twophase_files2 = os.listdir(pg2.pg_twophase_dir_path())
-    log.info(twophase_files2)
+    print(twophase_files2)
    assert twophase_files2.sort() == twophase_files.sort()

+    pg2 = pg2.start()
    conn2 = pg2.connect()
    cur2 = conn2.cursor()

--- a/test_runner/batch_others/test_vm_bits.py
+++ b/test_runner/batch_others/test_vm_bits.py
@@ -1,9 +1,5 @@
 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")

 #
@@ -15,7 +11,7 @@ def test_vm_bit_clear(pageserver: ZenithPageserver, postgres: PostgresFactory, p
    zenith_cli.run(["branch", "test_vm_bit_clear", "empty"])
    pg = postgres.create_start('test_vm_bit_clear')

-    log.info("postgres is running on 'test_vm_bit_clear' branch")
+    print("postgres is running on 'test_vm_bit_clear' branch")
    pg_conn = pg.connect()
    cur = pg_conn.cursor()

@@ -67,7 +63,7 @@ def test_vm_bit_clear(pageserver: ZenithPageserver, postgres: PostgresFactory, p
    # server at the right point-in-time avoids that full-page image.
    pg_new = postgres.create_start('test_vm_bit_clear_new')

-    log.info("postgres is running on 'test_vm_bit_clear_new' branch")
+    print("postgres is running on 'test_vm_bit_clear_new' branch")
    pg_new_conn = pg_new.connect()
    cur_new = pg_new_conn.cursor()

--- a/test_runner/batch_others/test_wal_acceptor.py
+++ b/test_runner/batch_others/test_wal_acceptor.py
@@ -1,18 +1,10 @@
 import pytest
 import random
 import time
-import os
-import subprocess
-import uuid

 from contextlib import closing
 from multiprocessing import Process, Value
-from fixtures.zenith_fixtures import WalAcceptorFactory, ZenithPageserver, PostgresFactory, PgBin
-from fixtures.utils import lsn_to_hex, mkdir_if_needed
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
+from fixtures.zenith_fixtures import WalAcceptorFactory, ZenithPageserver, PostgresFactory

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -206,92 +198,3 @@ def test_race_conditions(zenith_cli, pageserver: ZenithPageserver, postgres: Pos

    stop_value.value = 1
    proc.join()
-
-class ProposerPostgres:
-    """Object for running safekeepers sync with walproposer"""
-    def __init__(self, pgdata_dir: str, pg_bin: PgBin, timeline_id: str, tenant_id: str):
-        self.pgdata_dir: str = pgdata_dir
-        self.pg_bin: PgBin = pg_bin
-        self.timeline_id: str = timeline_id
-        self.tenant_id: str = tenant_id
-
-    def pg_data_dir_path(self) -> str:
-        """ Path to data directory """
-        return self.pgdata_dir
-
-    def config_file_path(self) -> str:
-        """ Path to postgresql.conf """
-        return os.path.join(self.pgdata_dir, 'postgresql.conf')
-
-    def create_dir_config(self, wal_acceptors: str):
-        """ Create dir and config for running --sync-safekeepers """
-
-        mkdir_if_needed(self.pg_data_dir_path())
-        with open(self.config_file_path(), "w") as f:
-            f.writelines([
-                "synchronous_standby_names = 'walproposer'\n",
-                f"zenith.zenith_timeline = '{self.timeline_id}'\n",
-                f"zenith.zenith_tenant = '{self.tenant_id}'\n",
-                f"wal_acceptors = '{wal_acceptors}'\n",
-            ])
-
-    def sync_safekeepers(self) -> str:
-        """
-        Run 'postgres --sync-safekeepers'.
-        Returns execution result, which is commit_lsn after sync.
-        """
-
-        command = ["postgres", "--sync-safekeepers"]
-        env = {
-            "PGDATA": self.pg_data_dir_path(),
-        }
-
-        basepath = self.pg_bin.run_capture(command, env)
-        stdout_filename = basepath + '.stdout'
-
-        with open(stdout_filename, 'r') as stdout_f:
-            stdout = stdout_f.read()
-            return stdout.strip("\n ")
-
-
-# insert wal in all safekeepers and run sync on proposer
-def test_sync_safekeepers(repo_dir: str, pg_bin: PgBin, wa_factory: WalAcceptorFactory):
-    wa_factory.start_n_new(3)
-
-    timeline_id = uuid.uuid4().hex
-    tenant_id = uuid.uuid4().hex
-
-    # write config for proposer
-    pgdata_dir = os.path.join(repo_dir, "proposer_pgdata")
-    pg = ProposerPostgres(pgdata_dir, pg_bin, timeline_id, tenant_id)
-    pg.create_dir_config(wa_factory.get_connstrs())
-
-    # valid lsn, which is not in the segment start, nor in zero segment
-    epoch_start_lsn = 0x16B9188  # 0/16B9188
-    begin_lsn = epoch_start_lsn
-
-    # append and commit WAL
-    lsn_after_append = []
-    for i in range(3):
-        res = wa_factory.instances[i].append_logical_message(
-            tenant_id,
-            timeline_id,
-            {
-                "lm_prefix": "prefix",
-                "lm_message": "message",
-                "set_commit_lsn": True,
-                "term": 2,
-                "begin_lsn": begin_lsn,
-                "epoch_start_lsn": epoch_start_lsn,
-                "truncate_lsn": epoch_start_lsn,
-            },
-        )
-        lsn_hex = lsn_to_hex(res["inserted_wal"]["end_lsn"])
-        lsn_after_append.append(lsn_hex)
-        log.info(f"safekeeper[{i}] lsn after append: {lsn_hex}")
-
-    # run sync safekeepers
-    lsn_after_sync = pg.sync_safekeepers()
-    log.info(f"lsn after sync = {lsn_after_sync}")
-
-    assert all(lsn_after_sync == lsn for lsn in lsn_after_append)
--- a/test_runner/batch_others/test_wal_acceptor_async.py
+++ b/test_runner/batch_others/test_wal_acceptor_async.py
@@ -1,162 +0,0 @@
-import asyncio
-import asyncpg
-import random
-
-from fixtures.zenith_fixtures import WalAcceptor, WalAcceptorFactory, ZenithPageserver, PostgresFactory, Postgres
-from typing import List
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root.wal_acceptor_async')
-
-pytest_plugins = ("fixtures.zenith_fixtures")
-
-
-class BankClient(object):
-    def __init__(self, conn: asyncpg.Connection, n_accounts, init_amount):
-        self.conn: asyncpg.Connection = conn
-        self.n_accounts = n_accounts
-        self.init_amount = init_amount
-
-    async def initdb(self):
-        await self.conn.execute('DROP TABLE IF EXISTS bank_accs')
-        await self.conn.execute('CREATE TABLE bank_accs(uid int primary key, amount int)')
-        await self.conn.execute('''
-            INSERT INTO bank_accs
-            SELECT *, $1 FROM generate_series(0, $2)
-        ''', self.init_amount, self.n_accounts - 1)
-        await self.conn.execute('DROP TABLE IF EXISTS bank_log')
-        await self.conn.execute('CREATE TABLE bank_log(from_uid int, to_uid int, amount int)')
-        
-        # TODO: Remove when https://github.com/zenithdb/zenith/issues/644 is fixed
-        await self.conn.execute('ALTER TABLE bank_accs SET (autovacuum_enabled = false)')
-        await self.conn.execute('ALTER TABLE bank_log SET (autovacuum_enabled = false)')
-
-    async def check_invariant(self):
-        row = await self.conn.fetchrow('SELECT sum(amount) AS sum FROM bank_accs')
-        assert row['sum'] == self.n_accounts * self.init_amount
-
-async def bank_transfer(conn: asyncpg.Connection, from_uid, to_uid, amount):
-    # avoid deadlocks by sorting uids
-    if from_uid > to_uid:
-        from_uid, to_uid, amount = to_uid, from_uid, -amount
-
-    async with conn.transaction():
-        await conn.execute(
-            'UPDATE bank_accs SET amount = amount + ($1) WHERE uid = $2',
-            amount, to_uid,
-        )
-        await conn.execute(
-            'UPDATE bank_accs SET amount = amount - ($1) WHERE uid = $2',
-            amount, from_uid,
-        )
-        await conn.execute('INSERT INTO bank_log VALUES ($1, $2, $3)',
-            from_uid, to_uid, amount,
-        )
-
-class WorkerStats(object):
-    def __init__(self, n_workers):
-        self.counters = [0] * n_workers
-        self.running = True
-
-    def reset(self):
-        self.counters = [0] * len(self.counters)
-
-    def inc_progress(self, worker_id):
-        self.counters[worker_id] += 1
-
-    def check_progress(self):
-        log.debug("Workers progress: {}".format(self.counters))
-
-        # every worker should finish at least one tx
-        assert all(cnt > 0 for cnt in self.counters)
-
-        progress = sum(self.counters)
-        log.info('All workers made {} transactions'.format(progress))
-
-
-async def run_random_worker(stats: WorkerStats, pg: Postgres, worker_id, n_accounts, max_transfer):
-    pg_conn = await pg.connect_async()
-    log.debug('Started worker {}'.format(worker_id))
-
-    while stats.running:
-        from_uid = random.randint(0, n_accounts - 1)
-        to_uid = (from_uid + random.randint(1, n_accounts - 1)) % n_accounts
-        amount = random.randint(1, max_transfer)
-
-        await bank_transfer(pg_conn, from_uid, to_uid, amount)
-        stats.inc_progress(worker_id)
-
-        log.debug('Executed transfer({}) {} => {}'.format(amount, from_uid, to_uid))
-
-    log.debug('Finished worker {}'.format(worker_id))
-
-    await pg_conn.close()
-
-
-# This test will run several iterations and check progress in each of them.
-# On each iteration 1 acceptor is stopped, and 2 others should allow
-# background workers execute transactions. In the end, state should remain
-# consistent.
-async def run_restarts_under_load(pg: Postgres, acceptors: List[WalAcceptor], n_workers=10):
-    n_accounts = 100
-    init_amount = 100000
-    max_transfer = 100
-    period_time = 10
-    iterations = 6
-
-    pg_conn = await pg.connect_async()
-    bank = BankClient(pg_conn, n_accounts=n_accounts, init_amount=init_amount)
-    # create tables and initial balances
-    await bank.initdb()
-
-    stats = WorkerStats(n_workers)
-    workers = []
-    for worker_id in range(n_workers):
-        worker = run_random_worker(stats, pg, worker_id, bank.n_accounts, max_transfer)
-        workers.append(asyncio.create_task(worker))
-
-
-    for it in range(iterations):
-        victim = acceptors[it % len(acceptors)]
-        victim.stop()
-
-        # Wait till previous victim recovers so it is ready for the next
-        # iteration by making any writing xact.
-        conn = await pg.connect_async()
-        await conn.execute(
-            'UPDATE bank_accs SET amount = amount WHERE uid = 1',
-            timeout=120
-        )
-        await conn.close()
-
-        stats.reset()
-        await asyncio.sleep(period_time)
-        # assert that at least one transaction has completed in every worker
-        stats.check_progress()
-
-        victim.start()
-
-    log.info('Iterations are finished, exiting coroutines...')
-    stats.running = False
-    # await all workers
-    await asyncio.gather(*workers)
-    # assert balances sum hasn't changed
-    await bank.check_invariant()
-    await pg_conn.close()
-
-
-# restart acceptors one by one, while executing and validating bank transactions
-def test_restarts_under_load(zenith_cli, pageserver: ZenithPageserver, postgres: PostgresFactory,
-                             wa_factory: WalAcceptorFactory):
-
-    wa_factory.start_n_new(3)
-
-    zenith_cli.run(["branch", "test_wal_acceptors_restarts_under_load", "empty"])
-    pg = postgres.create_start('test_wal_acceptors_restarts_under_load',
-                               wal_acceptors=wa_factory.get_connstrs())
-
-    asyncio.run(run_restarts_under_load(pg, wa_factory.instances))
-
-    # TODO: Remove when https://github.com/zenithdb/zenith/issues/644 is fixed
-    pg.stop()
--- a/test_runner/batch_pg_regress/test_pg_regress.py
+++ b/test_runner/batch_pg_regress/test_pg_regress.py
@@ -1,7 +1,7 @@
 import os

 from fixtures.utils import mkdir_if_needed
-from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver, check_restored_datadir_content
+from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

 pytest_plugins = ("fixtures.zenith_fixtures")

@@ -49,10 +49,3 @@ def test_pg_regress(pageserver: ZenithPageserver, postgres: PostgresFactory, pg_
    # logs the exact same data to `regression.out` anyway.
    with capsys.disabled():
        pg_bin.run(pg_regress_command, env=env, cwd=runpath)
-
-        # checkpoint one more time to ensure that the lsn we get is the latest one
-        pg.safe_psql('CHECKPOINT')
-        lsn = pg.safe_psql('select pg_current_wal_insert_lsn()')[0][0]
-
-        # Check that we restore the content of the datadir correctly
-        check_restored_datadir_content(zenith_cli, test_output_dir, pg, pageserver.service_port.pg)
--- a/test_runner/batch_pg_regress/test_zenith_regress.py
+++ b/test_runner/batch_pg_regress/test_zenith_regress.py
@@ -1,17 +1,13 @@
 import os

 from fixtures.utils import mkdir_if_needed
-from fixtures.zenith_fixtures import PageserverPort, PostgresFactory, check_restored_datadir_content
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
+from fixtures.zenith_fixtures import PostgresFactory

 pytest_plugins = ("fixtures.zenith_fixtures")


 def test_zenith_regress(postgres: PostgresFactory, pg_bin, zenith_cli, test_output_dir, pg_distrib_dir,
-                        base_dir, capsys, pageserver_port: PageserverPort):
+                        base_dir, capsys):

    # Create a branch for us
    zenith_cli.run(["branch", "test_zenith_regress", "empty"])
@@ -42,7 +38,7 @@ def test_zenith_regress(postgres: PostgresFactory, pg_bin, zenith_cli, test_outp
        '--inputdir={}'.format(src_path),
    ]

-    log.info(pg_regress_command)
+    print(pg_regress_command)
    env = {
        'PGPORT': str(pg.port),
        'PGUSER': pg.username,
@@ -54,10 +50,3 @@ def test_zenith_regress(postgres: PostgresFactory, pg_bin, zenith_cli, test_outp
    # logs the exact same data to `regression.out` anyway.
    with capsys.disabled():
        pg_bin.run(pg_regress_command, env=env, cwd=runpath)
-
-        # checkpoint one more time to ensure that the lsn we get is the latest one
-        pg.safe_psql('CHECKPOINT')
-        lsn = pg.safe_psql('select pg_current_wal_insert_lsn()')[0][0]
-
-        # Check that we restore the content of the datadir correctly
-        check_restored_datadir_content(zenith_cli, test_output_dir, pg, pageserver_port.pg)
--- a/test_runner/fixtures/benchmark_fixture.py
+++ b/test_runner/fixtures/benchmark_fixture.py
@@ -1,5 +1,6 @@
+from pprint import pprint
+
 import os
-import re
 import timeit
 import pathlib
 import uuid
@@ -77,7 +78,7 @@ class ZenithBenchmarkResults:

        self.results.append((test_name, metric_name, metric_value, unit))

-# Session scope fixture that initializes the results object
+# Sesssion scope fixture that initializes the results object
@pytest.fixture(autouse=True, scope='session')
 def zenbenchmark_global(request) -> Iterator[ZenithBenchmarkResults]:
    """
@@ -119,35 +120,6 @@ class ZenithBenchmarker:

        self.results.record(self.request.node.name, metric_name, end - start, 's')

-    def get_io_writes(self, pageserver) -> int:
-        """
-        Fetch the "cumulative # of bytes written" metric from the pageserver
-        """
-        # Fetch all the exposed prometheus metrics from page server
-        all_metrics = pageserver.http_client().get_metrics()
-        # Use a regular expression to extract the one we're interested in
-        #
-        # TODO: If we start to collect more of the prometheus metrics in the
-        # performance test suite like this, we should refactor this to load and
-        # parse all the metrics into a more convenient structure in one go.
-        #
-        # The metric should be an integer, as it's a number of bytes. But in general
-        # all prometheus metrics are floats. So to be pedantic, read it as a float
-        # and round to integer.
-        matches = re.search(r'pageserver_disk_io_bytes{io_operation="write"} (\S+)', all_metrics)
-        return int(round(float(matches.group(1))))
-
-    @contextmanager
-    def record_pageserver_writes(self, pageserver, metric_name):
-        """
-        Record bytes written by the pageserver during a test.
-        """
-        before = self.get_io_writes(pageserver)
-        yield
-        after = self.get_io_writes(pageserver)
-
-        self.results.record(self.request.node.name, metric_name, round((after - before) / (1024 * 1024)), 'MB')
-
@pytest.fixture(scope='function')
 def zenbenchmark(zenbenchmark_global, request) -> Iterator[ZenithBenchmarker]:
    """
--- a/test_runner/fixtures/log_helper.py
+++ b/test_runner/fixtures/log_helper.py
@@ -1,37 +0,0 @@
-import logging
-import logging.config
-import time
-
-# timestamp in UTC+-00:00 aka GMT
-class UTCFormatter(logging.Formatter):
-    converter = time.gmtime
-
-LOGGING = {
-    "version": 1,
-    "formatters": {
-    "defaultFormatter": {
-        "()": UTCFormatter,
-        "format": "%(asctime)s.%(msecs)-3d %(levelname)s [%(filename)s:%(lineno)d] %(message)s",
-        "datefmt": "%Y-%m-%d %H:%M:%S"
-    }
-    },
-    "handlers": {
-        "console": {
-            "class": "logging.StreamHandler",
-            "formatter": "defaultFormatter",
-            "level": "DEBUG",
-            "stream": "ext://sys.stderr"
-        }
-    },
-    "loggers": {
-        "root": {
-            "level": "DEBUG",
-            "handlers": ["console"]
-        },
-        "root.wal_acceptor_async": { 
-            "level": "INFO" # lot of logs on DEBUG level
-        }
-    }
-}
-
-logging.config.dictConfig(LOGGING)
--- a/test_runner/fixtures/utils.py
+++ b/test_runner/fixtures/utils.py
@@ -3,9 +3,6 @@ import subprocess

 from typing import Any, List

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')

 def get_self_dir() -> str:
    """ Get the path to the directory where this script lives. """
@@ -17,14 +14,13 @@ def mkdir_if_needed(path: str) -> None:

    Note this won't try to create intermediate directories.
    """
-    try:
-        os.mkdir(path)
-    except FileExistsError:
-        pass
-    assert os.path.isdir(path)
+    if os.path.exists(path):
+        assert os.path.isdir(path)
+        return
+    os.mkdir(path)


-def subprocess_capture(capture_dir: str, cmd: List[str], **kwargs: Any) -> str:
+def subprocess_capture(capture_dir: str, cmd: List[str], **kwargs: Any) -> None:
    """ Run a process and capture its output

    Output will go to files named "cmd_NNN.stdout" and "cmd_NNN.stderr"
@@ -32,7 +28,6 @@ def subprocess_capture(capture_dir: str, cmd: List[str], **kwargs: Any) -> str:
    counter.

    If those files already exist, we will overwrite them.
-    Returns basepath for files with captured output.
    """
    assert type(cmd) is list
    base = os.path.basename(cmd[0]) + '_{}'.format(global_counter())
@@ -42,11 +37,9 @@ def subprocess_capture(capture_dir: str, cmd: List[str], **kwargs: Any) -> str:

    with open(stdout_filename, 'w') as stdout_f:
        with open(stderr_filename, 'w') as stderr_f:
-            log.info('(capturing output to "{}.stdout")'.format(base))
+            print('(capturing output to "{}.stdout")'.format(base))
            subprocess.run(cmd, **kwargs, stdout=stdout_f, stderr=stderr_f)

-    return basepath
-

 _global_counter = 0

@@ -60,7 +53,3 @@ def global_counter() -> int:
    global _global_counter
    _global_counter += 1
    return _global_counter
-
-def lsn_to_hex(num: int) -> str:
-    """ Convert lsn from int to standard hex notation. """
-    return "{:X}/{:X}".format(num >> 32, num & 0xffffffff)
--- a/test_runner/fixtures/zenith_fixtures.py
+++ b/test_runner/fixtures/zenith_fixtures.py
@@ -1,19 +1,15 @@
 from dataclasses import dataclass
 from functools import cached_property
-import asyncpg
 import os
 import pathlib
 import uuid
 import jwt
-import json
 import psycopg2
 import pytest
 import shutil
 import signal
 import subprocess
 import time
-import filecmp
-import difflib

 from contextlib import closing
 from pathlib import Path
@@ -27,11 +23,6 @@ from typing_extensions import Literal
 import requests

 from .utils import (get_self_dir, mkdir_if_needed, subprocess_capture)
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 """
 This file contains pytest fixtures. A fixture is a test resource that can be
 summoned by placing its name in the test's arguments.
@@ -56,27 +47,8 @@ Fn = TypeVar('Fn', bound=Callable[..., Any])
 DEFAULT_OUTPUT_DIR = 'test_output'
 DEFAULT_POSTGRES_DIR = 'tmp_install'

-BASE_PORT = 15000
-WORKER_PORT_NUM = 100
-
-def pytest_configure(config):
-    """
-    Ensure that no unwanted daemons are running before we start testing.
-    Check that we do not owerflow available ports range.
-    """
-    numprocesses = config.getoption('numprocesses')
-    if numprocesses is not None and BASE_PORT + numprocesses * WORKER_PORT_NUM > 32768: # do not use ephemeral ports
-         raise Exception('Too many workers configured. Cannot distrubute ports for services.')
-
-    # does not use -c as it is not supported on macOS
-    cmd = ['pgrep', 'pageserver|postgres|wal_acceptor']
-    result = subprocess.run(cmd, stdout=subprocess.DEVNULL)
-    if result.returncode == 0:
-        # returncode of 0 means it found something.
-        # This is bad; we don't want any of those processes polluting the
-        # result of the test.
-        # NOTE this shows as an internal pytest error, there might be a better way
-        raise Exception('found interfering processes running')
+DEFAULT_PAGESERVER_PG_PORT = 64000
+DEFAULT_PAGESERVER_HTTP_PORT = 9898


 def determine_scope(fixture_name: str, config: Any) -> str:
@@ -101,6 +73,20 @@ def zenfixture(func: Fn) -> Fn:
    return pytest.fixture(func, scope=scope)


+@pytest.fixture(autouse=True, scope='session')
+def safety_check() -> None:
+    """ Ensure that no unwanted daemons are running before we start testing. """
+
+    # does not use -c as it is not supported on macOS
+    cmd = ['pgrep', 'pageserver|postgres|wal_acceptor']
+    result = subprocess.run(cmd, stdout=subprocess.DEVNULL)
+    if result.returncode == 0:
+        # returncode of 0 means it found something.
+        # This is bad; we don't want any of those processes polluting the
+        # result of the test.
+        raise Exception('found interfering processes running')
+
+
 class PgProtocol:
    """ Reusable connection logic """
    def __init__(self, host: str, port: int, username: Optional[str] = None):
@@ -136,21 +122,6 @@ class PgProtocol:
        conn.autocommit = autocommit
        return conn

-    async def connect_async(self, *, dbname: str = 'postgres', username: Optional[str] = None, password: Optional[str] = None) -> asyncpg.Connection:
-        """
-        Connect to the node from async python.
-        Returns asyncpg's connection object.
-        """
-
-        conn = await asyncpg.connect(
-            host=self.host,
-            port=self.port,
-            database=dbname,
-            user=username or self.username,
-            password=password,
-        )
-        return conn
-
    def safe_psql(self, query: str, **kwargs: Any) -> List[Any]:
        """
        Execute query against the node and return all rows.
@@ -191,34 +162,19 @@ class ZenithCli:

        >>> result = zenith_cli.run(...)
        >>> assert result.stderr == ""
-        >>> log.info(result.stdout)
+        >>> print(result.stdout)
        """

        assert type(arguments) == list

        args = [self.bin_zenith] + arguments
-        log.info('Running command "{}"'.format(' '.join(args)))
-
-        # Interceipt CalledProcessError and print more info
-        try:
-            res = subprocess.run(args,
-                                env=self.env,
-                                check=True,
-                                universal_newlines=True,
-                                stdout=subprocess.PIPE,
-                                stderr=subprocess.PIPE)
-        except subprocess.CalledProcessError as exc:
-            # this way command output will be in recorded and shown in CI in failure message
-            msg = f"""\
-            Run failed: {exc}
-              stdout: {exc.stdout}
-              stderr: {exc.stderr}
-            """
-            log.info(msg)
-
-            raise Exception(msg) from exc
-
-        return res
+        print('Running command "{}"'.format(' '.join(args)))
+        return subprocess.run(args,
+                              env=self.env,
+                              check=True,
+                              universal_newlines=True,
+                              stdout=subprocess.PIPE,
+                              stderr=subprocess.PIPE)


@zenfixture
@@ -255,13 +211,6 @@ class ZenithPageserverHttpClient(requests.Session):
        res.raise_for_status()
        return res.json()

-    def branch_detail(self, tenant_id: uuid.UUID, name: str) -> Dict:
-        res = self.get(
-            f"http://localhost:{self.port}/v1/branch/{tenant_id.hex}/{name}",
-        )
-        res.raise_for_status()
-        return res.json()
-
    def tenant_list(self) -> List[str]:
        res = self.get(f"http://localhost:{self.port}/v1/tenant")
        res.raise_for_status()
@@ -277,11 +226,6 @@ class ZenithPageserverHttpClient(requests.Session):
        res.raise_for_status()
        return res.json()

-    def get_metrics(self) -> str:
-        res = self.get(f"http://localhost:{self.port}/metrics")
-        res.raise_for_status()
-        return res.text
-

@dataclass
 class AuthKeys:
@@ -308,60 +252,24 @@ class AuthKeys:
        return token


-@zenfixture
-def worker_seq_no(worker_id: str):
-    # worker_id is a pytest-xdist fixture
-    # it can be master or gw<number>
-    # parse it to always get a number
-    if worker_id == 'master':
-        return 0
-    assert worker_id.startswith('gw')
-    return int(worker_id[2:])


-@zenfixture
-def worker_base_port(worker_seq_no: int):
-    # so we divide ports in ranges of 100 ports
-    # so workers have disjoint set of ports for services
-    return BASE_PORT + worker_seq_no * WORKER_PORT_NUM
-
-class PortDistributor:
-    def __init__(self, base_port: int, port_number: int) -> None:
-        self.iterator = iter(range(base_port, base_port + port_number))
-
-    def get_port(self) -> int:
-        try:
-            return next(self.iterator)
-        except StopIteration:
-            raise RuntimeError('port range configured for test is exhausted, consider enlarging the range')
-
-
-@zenfixture
-def port_distributor(worker_base_port):
-    return PortDistributor(base_port=worker_base_port, port_number=WORKER_PORT_NUM)
-
-@dataclass
-class PageserverPort:
-    pg: int
-    http: int
-

 class ZenithPageserver(PgProtocol):
    """ An object representing a running pageserver. """
-    def __init__(self, zenith_cli: ZenithCli, repo_dir: str, port: PageserverPort):
-        super().__init__(host='localhost', port=port.pg)
+    def __init__(self, zenith_cli: ZenithCli, repo_dir: str):
+        super().__init__(host='localhost', port=DEFAULT_PAGESERVER_PG_PORT)
        self.zenith_cli = zenith_cli
        self.running = False
        self.initial_tenant = None
        self.repo_dir = repo_dir
-        self.service_port = port # do not shadow PgProtocol.port which is just int

    def init(self, enable_auth: bool = False) -> 'ZenithPageserver':
        """
        Initialize the repository, i.e. run "zenith init".
        Returns self.
        """
-        cmd = ['init', f'--pageserver-pg-port={self.service_port.pg}', f'--pageserver-http-port={self.service_port.http}']
+        cmd = ['init']
        if enable_auth:
            cmd.append('--enable-auth')
        self.zenith_cli.run(cmd)
@@ -411,23 +319,13 @@ class ZenithPageserver(PgProtocol):

    def http_client(self, auth_token: Optional[str] = None):
        return ZenithPageserverHttpClient(
-            port=self.service_port.http,
+            port=DEFAULT_PAGESERVER_HTTP_PORT,
            auth_token=auth_token,
        )


-
-
@zenfixture
-def pageserver_port(port_distributor: PortDistributor) -> PageserverPort:
-    pg = port_distributor.get_port()
-    http = port_distributor.get_port()
-    log.info(f"pageserver_port: pg={pg} http={http}")
-    return PageserverPort(pg=pg, http=http)
-
-
-@zenfixture
-def pageserver(zenith_cli: ZenithCli, repo_dir: str, pageserver_port: PageserverPort) -> Iterator[ZenithPageserver]:
+def pageserver(zenith_cli: ZenithCli, repo_dir: str) -> Iterator[ZenithPageserver]:
    """
    The 'pageserver' fixture provides a Page Server that's up and running.

@@ -439,14 +337,15 @@ def pageserver(zenith_cli: ZenithCli, repo_dir: str, pageserver_port: Pageserver
    By convention, the test branches are named after the tests. For example,
    test called 'test_foo' would create and use branches with the 'test_foo' prefix.
    """
-    ps = ZenithPageserver(zenith_cli=zenith_cli, repo_dir=repo_dir, port=pageserver_port).init().start()
+
+    ps = ZenithPageserver(zenith_cli, repo_dir).init().start()
    # For convenience in tests, create a branch from the freshly-initialized cluster.
    zenith_cli.run(["branch", "empty", "main"])

    yield ps

    # After the yield comes any cleanup code we need.
-    log.info('Starting pageserver cleanup')
+    print('Starting pageserver cleanup')
    ps.stop()

 class PgBin:
@@ -484,26 +383,24 @@ class PgBin:
        """

        self._fixpath(command)
-        log.info('Running command "{}"'.format(' '.join(command)))
+        print('Running command "{}"'.format(' '.join(command)))
        env = self._build_env(env)
        subprocess.run(command, env=env, cwd=cwd, check=True)

    def run_capture(self,
                    command: List[str],
                    env: Optional[Env] = None,
-                    cwd: Optional[str] = None,
-                    **kwargs: Any) -> None:
+                    cwd: Optional[str] = None) -> None:
        """
        Run one of the postgres binaries, with stderr and stdout redirected to a file.

-        This is just like `run`, but for chatty programs. Returns basepath for files
-        with captured output.
+        This is just like `run`, but for chatty programs.
        """

        self._fixpath(command)
-        log.info('Running command "{}"'.format(' '.join(command)))
+        print('Running command "{}"'.format(' '.join(command)))
        env = self._build_env(env)
-        return subprocess_capture(self.log_dir, command, env=env, cwd=cwd, check=True, **kwargs)
+        subprocess_capture(self.log_dir, command, env=env, cwd=cwd, check=True)


@zenfixture
@@ -511,8 +408,8 @@ def pg_bin(test_output_dir: str, pg_distrib_dir: str) -> PgBin:
    return PgBin(test_output_dir, pg_distrib_dir)

@pytest.fixture
-def pageserver_auth_enabled(zenith_cli: ZenithCli, repo_dir: str, pageserver_port: PageserverPort):
-    with ZenithPageserver(zenith_cli=zenith_cli, repo_dir=repo_dir, port=pageserver_port).init(enable_auth=True).start() as ps:
+def pageserver_auth_enabled(zenith_cli: ZenithCli, repo_dir: str):
+    with ZenithPageserver(zenith_cli, repo_dir).init(enable_auth=True).start() as ps:
        # For convenience in tests, create a branch from the freshly-initialized cluster.
        zenith_cli.run(["branch", "empty", "main"])
        yield ps
@@ -537,6 +434,7 @@ class Postgres(PgProtocol):
        branch: str,
        wal_acceptors: Optional[str] = None,
        config_lines: Optional[List[str]] = None,
+        config_only: bool = False,
    ) -> 'Postgres':
        """
        Create the pg data directory.
@@ -548,7 +446,10 @@ class Postgres(PgProtocol):
        if not config_lines:
            config_lines = []

-        self.zenith_cli.run(['pg', 'create', branch, f'--tenantid={self.tenant_id}', f'--port={self.port}'])
+        if config_only:
+            self.zenith_cli.run(['pg', 'create', '--config-only', branch, f'--tenantid={self.tenant_id}'])
+        else:
+            self.zenith_cli.run(['pg', 'create', branch, f'--tenantid={self.tenant_id}'])
        self.branch = branch
        path = pathlib.Path('pgdatadirs') / 'tenants' / self.tenant_id / self.branch
        self.pgdata_dir = os.path.join(self.repo_dir, path)
@@ -569,12 +470,12 @@ class Postgres(PgProtocol):

        assert self.branch is not None

-        log.info(f"Starting postgres on branch {self.branch}")
+        print(f"Starting postgres on brach {self.branch}")

-        run_result = self.zenith_cli.run(['pg', 'start', self.branch, f'--tenantid={self.tenant_id}', f'--port={self.port}'])
+        self.zenith_cli.run(['pg', 'start', self.branch, f'--tenantid={self.tenant_id}'])
        self.running = True

-        log.info(f"stdout: {run_result.stdout}")
+        self.pg_bin.run(['pg_controldata', self.pg_data_dir_path()])

        return self

@@ -671,6 +572,7 @@ class Postgres(PgProtocol):
            branch=branch,
            wal_acceptors=wal_acceptors,
            config_lines=config_lines,
+            config_only=True,
        ).start()

        return self
@@ -681,15 +583,16 @@ class Postgres(PgProtocol):
    def __exit__(self, exc_type, exc, tb):
        self.stop()

+
 class PostgresFactory:
    """ An object representing multiple running postgres daemons. """
-    def __init__(self, zenith_cli: ZenithCli, repo_dir: str, pg_bin: PgBin, initial_tenant: str, port_distributor: PortDistributor):
+    def __init__(self, zenith_cli: ZenithCli, repo_dir: str, pg_bin: PgBin, initial_tenant: str, base_port: int = 55431):
        self.zenith_cli = zenith_cli
        self.repo_dir = repo_dir
        self.num_instances = 0
        self.instances: List[Postgres] = []
        self.initial_tenant: str = initial_tenant
-        self.port_distributor = port_distributor
+        self.base_port = base_port
        self.pg_bin = pg_bin

    def create_start(
@@ -699,13 +602,15 @@ class PostgresFactory:
        wal_acceptors: Optional[str] = None,
        config_lines: Optional[List[str]] = None
    ) -> Postgres:
+
        pg = Postgres(
            zenith_cli=self.zenith_cli,
            repo_dir=self.repo_dir,
            pg_bin=self.pg_bin,
            tenant_id=tenant_id or self.initial_tenant,
-            port=self.port_distributor.get_port(),
+            port=self.base_port + self.num_instances + 1,
        )
+
        self.num_instances += 1
        self.instances.append(pg)

@@ -728,7 +633,7 @@ class PostgresFactory:
            repo_dir=self.repo_dir,
            pg_bin=self.pg_bin,
            tenant_id=tenant_id or self.initial_tenant,
-            port=self.port_distributor.get_port(),
+            port=self.base_port + self.num_instances + 1,
        )

        self.num_instances += 1
@@ -753,7 +658,7 @@ class PostgresFactory:
            repo_dir=self.repo_dir,
            pg_bin=self.pg_bin,
            tenant_id=tenant_id or self.initial_tenant,
-            port=self.port_distributor.get_port(),
+            port=self.base_port + self.num_instances + 1,
        )

        self.num_instances += 1
@@ -777,19 +682,13 @@ def initial_tenant(pageserver: ZenithPageserver):


@zenfixture
-def postgres(zenith_cli: ZenithCli, initial_tenant: str, repo_dir: str, pg_bin: PgBin, port_distributor: PortDistributor) -> Iterator[PostgresFactory]:
-    pgfactory = PostgresFactory(
-        zenith_cli=zenith_cli,
-        repo_dir=repo_dir,
-        pg_bin=pg_bin,
-        initial_tenant=initial_tenant,
-        port_distributor=port_distributor,
-    )
+def postgres(zenith_cli: ZenithCli, initial_tenant: str, repo_dir: str, pg_bin: PgBin) -> Iterator[PostgresFactory]:
+    pgfactory = PostgresFactory(zenith_cli, repo_dir, pg_bin, initial_tenant=initial_tenant)

    yield pgfactory

    # After the yield comes any cleanup code we need.
-    log.info('Starting postgres cleanup')
+    print('Starting postgres cleanup')
    pgfactory.stop_all()

 def read_pid(path: Path):
@@ -800,11 +699,10 @@ def read_pid(path: Path):
@dataclass
 class WalAcceptor:
    """ An object representing a running wal acceptor daemon. """
-    wa_bin_path: Path
+    bin_path: Path
    data_dir: Path
    port: int
    num: int # identifier for logging
-    pageserver_port: int
    auth_token: Optional[str] = None

    def start(self) -> 'WalAcceptor':
@@ -812,15 +710,15 @@ class WalAcceptor:
        self.data_dir.mkdir(parents=True, exist_ok=True)
        self.pidfile.unlink(missing_ok=True)

-        cmd = [str(self.wa_bin_path)]
+        cmd = [str(self.bin_path)]
        cmd.extend(["-D", str(self.data_dir)])
-        cmd.extend(["-l", f"localhost:{self.port}"])
+        cmd.extend(["-l", "localhost:{}".format(self.port)])
        cmd.append("--daemonize")
        cmd.append("--no-sync")
        # Tell page server it can receive WAL from this WAL safekeeper
-        cmd.extend(["--pageserver", f"localhost:{self.pageserver_port}"])
+        cmd.extend(["--pageserver", "localhost:{}".format(DEFAULT_PAGESERVER_PG_PORT)])
        cmd.extend(["--recall", "1 second"])
-        log.info('Running command "{}"'.format(' '.join(cmd)))
+        print('Running command "{}"'.format(' '.join(cmd)))
        env = {'PAGESERVER_AUTH_TOKEN': self.auth_token} if self.auth_token else None
        subprocess.run(cmd, check=True, env=env)

@@ -849,10 +747,10 @@ class WalAcceptor:
        return pid

    def stop(self) -> 'WalAcceptor':
-        log.info('Stopping wal acceptor {}'.format(self.num))
+        print('Stopping wal acceptor {}'.format(self.num))
        pid = self.get_pid()
        if pid is None:
-            log.info("Wal acceptor {} is not running".format(self.num))
+            print("Wal acceptor {} is not running".format(self.num))
            return self

        try:
@@ -862,49 +760,27 @@ class WalAcceptor:
            pass # pidfile might be obsolete
        return self

-    def append_logical_message(self, tenant_id: str, timeline_id: str, request: Dict[str, Any]) -> Dict[str, Any]:
-        """
-        Send JSON_CTRL query to append LogicalMessage to WAL and modify 
-        safekeeper state. It will construct LogicalMessage from provided
-        prefix and message, and then will write it to WAL.
-        """
-
-        # "replication=0" hacks psycopg not to send additional queries
-        # on startup, see https://github.com/psycopg/psycopg2/pull/482
-        connstr = f"host=localhost port={self.port} replication=0 options='-c ztimelineid={timeline_id} ztenantid={tenant_id}'"
-
-        with closing(psycopg2.connect(connstr)) as conn:
-            # server doesn't support transactions
-            conn.autocommit = True
-            with conn.cursor() as cur:
-                request_json = json.dumps(request)
-                log.info(f"JSON_CTRL request on port {self.port}: {request_json}")
-                cur.execute("JSON_CTRL " + request_json)
-                all = cur.fetchall()
-                log.info(f"JSON_CTRL response: {all[0][0]}")
-                return json.loads(all[0][0])

 class WalAcceptorFactory:
    """ An object representing multiple running wal acceptors. """
-    def __init__(self, zenith_binpath: Path, data_dir: Path, pageserver_port: int, port_distributor: PortDistributor):
-        self.wa_bin_path = zenith_binpath / 'wal_acceptor'
+    def __init__(self, zenith_binpath: Path, data_dir: Path):
+        self.wa_binpath = zenith_binpath / 'wal_acceptor'
        self.data_dir = data_dir
        self.instances: List[WalAcceptor] = []
-        self.port_distributor = port_distributor
-        self.pageserver_port = pageserver_port
+        self.initial_port = 54321

    def start_new(self, auth_token: Optional[str] = None) -> WalAcceptor:
        """
        Start new wal acceptor.
        """
+
        wa_num = len(self.instances)
        wa = WalAcceptor(
-            wa_bin_path=self.wa_bin_path,
-            data_dir=self.data_dir / "wal_acceptor_{}".format(wa_num),
-            port=self.port_distributor.get_port(),
-            num=wa_num,
-            pageserver_port=self.pageserver_port,
-            auth_token=auth_token,
+            self.wa_binpath,
+            self.data_dir / "wal_acceptor_{}".format(wa_num),
+            self.initial_port + wa_num,
+            wa_num,
+            auth_token,
        )
        wa.start()
        self.instances.append(wa)
@@ -929,17 +805,12 @@ class WalAcceptorFactory:


@zenfixture
-def wa_factory(zenith_binpath: str, repo_dir: str, pageserver_port: PageserverPort, port_distributor: PortDistributor) -> Iterator[WalAcceptorFactory]:
+def wa_factory(zenith_binpath: str, repo_dir: str) -> Iterator[WalAcceptorFactory]:
    """ Gives WalAcceptorFactory providing wal acceptors. """
-    wafactory = WalAcceptorFactory(
-        zenith_binpath=Path(zenith_binpath),
-        data_dir=Path(repo_dir) / "wal_acceptors",
-        pageserver_port=pageserver_port.pg,
-        port_distributor=port_distributor,
-    )
+    wafactory = WalAcceptorFactory(Path(zenith_binpath), Path(repo_dir) / "wal_acceptors")
    yield wafactory
    # After the yield comes any cleanup code we need.
-    log.info('Starting wal acceptors cleanup')
+    print('Starting wal acceptors cleanup')
    wafactory.stop_all()


@@ -948,7 +819,7 @@ def base_dir() -> str:
    """ find the base directory (currently this is the git root) """

    base_dir = os.path.normpath(os.path.join(get_self_dir(), '../..'))
-    log.info(f'base_dir is {base_dir}')
+    print('\nbase_dir is', base_dir)
    return base_dir


@@ -977,7 +848,7 @@ def test_output_dir(request: Any, top_output_dir: str) -> str:
        test_name = 'shared'

    test_output_dir = os.path.join(top_output_dir, test_name)
-    log.info(f'test_output_dir is {test_output_dir}')
+    print('test_output_dir is', test_output_dir)
    shutil.rmtree(test_output_dir, ignore_errors=True)
    mkdir_if_needed(test_output_dir)
    return test_output_dir
@@ -1019,7 +890,7 @@ def pg_distrib_dir(base_dir: str) -> str:
        pg_dir = env_postgres_bin
    else:
        pg_dir = os.path.normpath(os.path.join(base_dir, DEFAULT_POSTGRES_DIR))
-    log.info(f'postgres dir is {pg_dir}')
+    print('postgres dir is', pg_dir)
    if not os.path.exists(os.path.join(pg_dir, 'bin/postgres')):
        raise Exception('postgres not found at "{}"'.format(pg_dir))
    return pg_dir
@@ -1040,85 +911,3 @@ class TenantFactory:
@zenfixture
 def tenant_factory(zenith_cli: ZenithCli):
    return TenantFactory(zenith_cli)
-
-#
-# Test helpers
-#
-def list_files_to_compare(pgdata_dir: str):
-    pgdata_files = []
-    for root, _file, filenames in os.walk(pgdata_dir):
-        for filename in filenames:
-            rel_dir = os.path.relpath(root, pgdata_dir)
-            # Skip some dirs and files we don't want to compare
-            skip_dirs = ['pg_wal', 'pg_stat', 'pg_stat_tmp', 'pg_subtrans', 'pg_logical']
-            skip_files = ['pg_internal.init', 'pg.log', 'zenith.signal', 'postgresql.conf',
-                        'postmaster.opts', 'postmaster.pid', 'pg_control']
-            if rel_dir not in skip_dirs and filename not in skip_files:
-                rel_file = os.path.join(rel_dir, filename)
-                pgdata_files.append(rel_file)
-
-    pgdata_files.sort()
-    log.info(pgdata_files)
-    return pgdata_files
-
-# pg is the existing and running compute node, that we want to compare with a basebackup
-def check_restored_datadir_content(zenith_cli: ZenithCli, test_output_dir: str, pg: Postgres, pageserver_pg_port: int):
-
-    # Get the timeline ID of our branch. We need it for the 'basebackup' command
-    with closing(pg.connect()) as conn:
-        with conn.cursor() as cur:
-            cur.execute("SHOW zenith.zenith_timeline")
-            timeline = cur.fetchone()[0]
-
-    # stop postgres to ensure that files won't change
-    pg.stop()
-
-    # Take a basebackup from pageserver
-    restored_dir_path = os.path.join(test_output_dir, f"{pg.branch}_restored_datadir")
-    mkdir_if_needed(restored_dir_path)
-
-    psql_path = os.path.join(pg.pg_bin.pg_bin_path, 'psql')
-
-    cmd = rf"""
-        {psql_path}                                    \
-            --no-psqlrc                                \
-            postgres://localhost:{pageserver_pg_port}  \
-            -c 'basebackup {pg.tenant_id} {timeline}'  \
-         | tar -x -C {restored_dir_path}
-    """
-
-    subprocess.check_call(cmd, shell=True)
-
-    # list files we're going to compare
-    pgdata_files = list_files_to_compare(pg.pgdata_dir)
-    restored_files = list_files_to_compare(restored_dir_path)
-
-    # check that file sets are equal
-    assert pgdata_files == restored_files
-
-    # compare content of the files
-    # filecmp returns (match, mismatch, error) lists
-    # We've already filtered all mismatching files in list_files_to_compare(),
-    # so here expect that the content is identical
-    (match, mismatch, error) = filecmp.cmpfiles(pg.pgdata_dir,
-                                                restored_dir_path,
-                                                pgdata_files,
-                                                shallow=False)
-    log.info('filecmp result mismatch and error lists:')
-    log.info(mismatch)
-    log.info(error)
-
-    for f in mismatch:
-
-        f1 = os.path.join(pg.pgdata_dir, f)
-        f2 = os.path.join(restored_dir_path, f)
-        stdout_filename = "{}.filediff".format(f2)
-
-        with open(stdout_filename, 'w') as stdout_f:
-            subprocess.run("xxd -b {} > {}.hex ".format(f1, f1), shell=True)
-            subprocess.run("xxd -b {} > {}.hex ".format(f2, f2), shell=True)
-
-            cmd = ['diff {}.hex {}.hex'.format(f1, f2)]
-            subprocess.run(cmd, stdout=stdout_f, shell=True)
-
-    assert (mismatch, error) == ([], [])
--- a/test_runner/performance/test_bulk_insert.py
+++ b/test_runner/performance/test_bulk_insert.py
@@ -1,64 +0,0 @@
-import os
-from contextlib import closing
-from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver
-
-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
-pytest_plugins = ("fixtures.zenith_fixtures", "fixtures.benchmark_fixture")
-
-def get_timeline_size(repo_dir: str, tenantid: str, timelineid: str):
-    path = "{}/tenants/{}/timelines/{}".format(repo_dir, tenantid, timelineid)
-
-    totalbytes = 0
-    for root, dirs, files in os.walk(path):
-        for name in files:
-            totalbytes += os.path.getsize(os.path.join(root, name))
-
-        if 'wal' in dirs:
-            dirs.remove('wal')  # don't visit 'wal' subdirectory
-
-    return totalbytes
-
-#
-# Run bulk INSERT test.
-#
-# Collects metrics:
-#
-# 1. Time to INSERT 5 million rows
-# 2. Disk writes
-# 3. Disk space used
-#
-def test_bulk_insert(postgres: PostgresFactory, pageserver: ZenithPageserver, pg_bin, zenith_cli, zenbenchmark, repo_dir: str):
-    # Create a branch for us
-    zenith_cli.run(["branch", "test_bulk_insert", "empty"])
-
-    pg = postgres.create_start('test_bulk_insert')
-    log.info("postgres is running on 'test_bulk_insert' branch")
-
-    # Open a connection directly to the page server that we'll use to force
-    # flushing the layers to disk
-    psconn = pageserver.connect();
-    pscur = psconn.cursor()
-
-    # Get the timeline ID of our branch. We need it for the 'do_gc' command
-    with closing(pg.connect()) as conn:
-        with conn.cursor() as cur:
-            cur.execute("SHOW zenith.zenith_timeline")
-            timeline = cur.fetchone()[0]
-
-            cur.execute("create table huge (i int, j int);")
-
-            # Run INSERT, recording the time and I/O it takes
-            with zenbenchmark.record_pageserver_writes(pageserver, 'pageserver_writes'):
-                with zenbenchmark.record_duration('insert'):
-                    cur.execute("insert into huge values (generate_series(1, 5000000), 0);")
-
-                    # Flush the layers from memory to disk. This is included in the reported
-                    # time and I/O
-                    pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
-
-            # Report disk space used by the repository
-            timeline_size = get_timeline_size(repo_dir, pageserver.initial_tenant, timeline)
-            zenbenchmark.record('size', timeline_size / (1024*1024), 'MB')
--- a/test_runner/performance/test_perf_pgbench.py
+++ b/test_runner/performance/test_perf_pgbench.py
@@ -2,10 +2,6 @@ import os
 from contextlib import closing
 from fixtures.zenith_fixtures import PostgresFactory, ZenithPageserver

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures", "fixtures.benchmark_fixture")

 def get_timeline_size(repo_dir: str, tenantid: str, timelineid: str):
@@ -35,7 +31,7 @@ def test_pgbench(postgres: PostgresFactory, pageserver: ZenithPageserver, pg_bin
    zenith_cli.run(["branch", "test_pgbench_perf", "empty"])

    pg = postgres.create_start('test_pgbench_perf')
-    log.info("postgres is running on 'test_pgbench_perf' branch")
+    print("postgres is running on 'test_pgbench_perf' branch")

    # Open a connection directly to the page server that we'll use to force
    # flushing the layers to disk
@@ -50,14 +46,13 @@ def test_pgbench(postgres: PostgresFactory, pageserver: ZenithPageserver, pg_bin

    connstr = pg.connstr()

-    # Initialize pgbench database, recording the time and I/O it takes
-    with zenbenchmark.record_pageserver_writes(pageserver, 'pageserver_writes'):
-        with zenbenchmark.record_duration('init'):
-            pg_bin.run_capture(['pgbench', '-s5', '-i', connstr])
+    # Initialize pgbench database
+    with zenbenchmark.record_duration('init'):
+        pg_bin.run_capture(['pgbench', '-s5', '-i', connstr])

-            # Flush the layers from memory to disk. This is included in the reported
-            # time and I/O
-            pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")
+        # Flush the layers from memory to disk. The time to do that is included in the
+        # reported init time.
+        pscur.execute(f"do_gc {pageserver.initial_tenant} {timeline} 0")

    # Run pgbench for 5000 transactions
    with zenbenchmark.record_duration('5000_xacts'):
--- a/test_runner/test_broken.py
+++ b/test_runner/test_broken.py
@@ -1,10 +1,6 @@
 import pytest
 import os

-import logging
-import fixtures.log_helper  # configures loggers
-log = logging.getLogger('root')
-
 pytest_plugins = ("fixtures.zenith_fixtures")
 """
 Use this test to see what happens when tests fail.
@@ -26,7 +22,7 @@ def test_broken(zenith_cli, pageserver, postgres, pg_bin):
    zenith_cli.run(["branch", "test_broken", "empty"])

    postgres.create_start("test_broken")
-    log.info('postgres is running')
+    print('postgres is running')

-    log.info('THIS NEXT COMMAND WILL FAIL:')
+    print('THIS NEXT COMMAND WILL FAIL:')
    pg_bin.run('pgbench -i_am_a_broken_test'.split())
--- a/vendor/postgres
+++ b/vendor/postgres
--- a/walkeeper/Cargo.toml
+++ b/walkeeper/Cargo.toml
@@ -13,12 +13,16 @@ bytes = "1.0.1"
 byteorder = "1.4.3"
 fs2 = "0.4.3"
 lazy_static = "1.4.0"
-serde_json = "1"
+slog-stdlog = "4.1.0"
+slog-async = "2.6.0"
+slog-scope = "4.4.0"
+slog-term = "2.8.0"
+slog = "2.7.0"
 log = "0.4.14"
 clap = "2.33.0"
 daemonize = "0.4.1"
 rust-s3 = { version = "0.27.0-rc4", features = ["no-verify-ssl"] }
-tokio = "1.11"
+tokio = { version = "1.3.0", features = ["full"] }
 tokio-stream = { version = "0.1.4" }
 postgres-protocol = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
 postgres = { git = "https://github.com/zenithdb/rust-postgres.git", rev="9eb0dbfbeb6a6c1b79099b9f7ae4a8c021877858" }
--- a/walkeeper/src/bin/wal_acceptor.rs
+++ b/walkeeper/src/bin/wal_acceptor.rs
@@ -1,14 +1,15 @@
 //
 // Main entry point for the wal_acceptor executable
 //
-use anyhow::Result;
+use anyhow::{Context, Result};
 use clap::{App, Arg};
 use daemonize::Daemonize;
 use log::*;
-use std::env;
+use slog::Drain;
 use std::path::{Path, PathBuf};
 use std::thread;
-use zenith_utils::logging;
+use std::{env, io};
+use std::{fs::File, fs::OpenOptions};

 use walkeeper::s3_offload;
 use walkeeper::wal_service;
@@ -112,7 +113,20 @@ fn main() -> Result<()> {

 fn start_wal_acceptor(conf: WalAcceptorConf) -> Result<()> {
    let log_filename = conf.data_dir.join("wal_acceptor.log");
-    let (_scope_guard, log_file) = logging::init(log_filename, conf.daemonize)?;
+    // Don't open the same file for output multiple times;
+    // the different fds could overwrite each other's output.
+    let log_file = OpenOptions::new()
+        .create(true)
+        .append(true)
+        .open(&log_filename)
+        .with_context(|| format!("failed to open {:?}", &log_filename))?;
+
+    // Initialize logger
+    let logger_file = log_file.try_clone().unwrap();
+    let _scope_guard = init_logging(&conf, logger_file)?;
+    let _log_guard = slog_stdlog::init().unwrap();
+    // Note: this `info!(...)` macro comes from `log` crate
+    info!("standard logging redirected to slog");

    if conf.daemonize {
        info!("daemonizing...");
@@ -165,3 +179,29 @@ fn start_wal_acceptor(conf: WalAcceptorConf) -> Result<()> {
    }
    Ok(())
 }
+
+fn init_logging(
+    conf: &WalAcceptorConf,
+    log_file: File,
+) -> Result<slog_scope::GlobalLoggerGuard, io::Error> {
+    if conf.daemonize {
+        let decorator = slog_term::PlainSyncDecorator::new(log_file);
+        let drain = slog_term::CompactFormat::new(decorator).build();
+        let drain = slog::Filter::new(drain, |record: &slog::Record| {
+            record.level().is_at_least(slog::Level::Info)
+        });
+        let drain = std::sync::Mutex::new(drain).fuse();
+        let logger = slog::Logger::root(drain, slog::o!());
+        Ok(slog_scope::set_global_logger(logger))
+    } else {
+        let decorator = slog_term::TermDecorator::new().build();
+        let drain = slog_term::FullFormat::new(decorator).build().fuse();
+        let drain = slog::Filter::new(drain, |record: &slog::Record| {
+            record.level().is_at_least(slog::Level::Info)
+        })
+        .fuse();
+        let drain = slog_async::Async::new(drain).chan_size(1000).build().fuse();
+        let logger = slog::Logger::root(drain, slog::o!());
+        Ok(slog_scope::set_global_logger(logger))
+    }
+}
--- a/walkeeper/src/json_ctrl.rs
+++ b/walkeeper/src/json_ctrl.rs
@@ -1,249 +0,0 @@
-//!
-//! This module implements JSON_CTRL protocol, which allows exchange
-//! JSON messages over psql for testing purposes.
-//!
-//! Currently supports AppendLogicalMessage, which is used for WAL
-//! modifications in tests.
-//!
-
-use anyhow::{anyhow, Result};
-use bytes::{BufMut, Bytes, BytesMut};
-use crc32c::crc32c_append;
-use log::*;
-use serde::{Deserialize, Serialize};
-
-use crate::safekeeper::{AcceptorProposerMessage, AppendResponse};
-use crate::safekeeper::{
-    AppendRequest, AppendRequestHeader, ProposerAcceptorMessage, ProposerGreeting,
-};
-use crate::safekeeper::{SafeKeeperState, Term};
-use crate::send_wal::SendWalHandler;
-use crate::timeline::TimelineTools;
-use postgres_ffi::pg_constants;
-use postgres_ffi::xlog_utils;
-use postgres_ffi::{uint32, uint64, Oid, XLogRecord};
-use zenith_utils::lsn::Lsn;
-use zenith_utils::postgres_backend::PostgresBackend;
-use zenith_utils::pq_proto::{BeMessage, RowDescriptor, TEXT_OID};
-
-#[derive(Serialize, Deserialize, Debug)]
-struct AppendLogicalMessage {
-    // prefix and message to build LogicalMessage
-    lm_prefix: String,
-    lm_message: String,
-
-    // if true, commit_lsn will match flush_lsn after append
-    set_commit_lsn: bool,
-
-    // fields from AppendRequestHeader
-    term: Term,
-    epoch_start_lsn: Lsn,
-    begin_lsn: Lsn,
-    truncate_lsn: Lsn,
-}
-
-#[derive(Serialize, Deserialize)]
-struct AppendResult {
-    // safekeeper state after append
-    state: SafeKeeperState,
-    // info about new record in the WAL
-    inserted_wal: InsertedWAL,
-}
-
-/// Handles command to craft logical message WAL record with given
-/// content, and then append it with specified term and lsn. This
-/// function is used to test safekeepers in different scenarios.
-pub fn handle_json_ctrl(
-    swh: &mut SendWalHandler,
-    pgb: &mut PostgresBackend,
-    cmd: &Bytes,
-) -> Result<()> {
-    let cmd = cmd
-        .strip_prefix(b"JSON_CTRL")
-        .ok_or_else(|| anyhow!("invalid prefix"))?;
-    // trim zeroes in the end
-    let cmd = cmd.strip_suffix(&[0u8]).unwrap_or(cmd);
-
-    let append_request: AppendLogicalMessage = serde_json::from_slice(cmd)?;
-    info!("JSON_CTRL request: {:?}", append_request);
-
-    // need to init safekeeper state before AppendRequest
-    prepare_safekeeper(swh)?;
-
-    let inserted_wal = append_logical_message(swh, append_request)?;
-    let response = AppendResult {
-        state: swh.timeline.get().get_info(),
-        inserted_wal,
-    };
-    let response_data = serde_json::to_vec(&response)?;
-
-    pgb.write_message_noflush(&BeMessage::RowDescription(&[RowDescriptor {
-        name: b"json",
-        typoid: TEXT_OID,
-        typlen: -1,
-        ..Default::default()
-    }]))?
-    .write_message_noflush(&BeMessage::DataRow(&[Some(&response_data)]))?
-    .write_message(&BeMessage::CommandComplete(b"JSON_CTRL"))?;
-    Ok(())
-}
-
-/// Prepare safekeeper to process append requests without crashes,
-/// by sending ProposerGreeting with default server.wal_seg_size.
-fn prepare_safekeeper(swh: &mut SendWalHandler) -> Result<()> {
-    let greeting_request = ProposerAcceptorMessage::Greeting(ProposerGreeting {
-        protocol_version: 1, // current protocol
-        pg_version: 0,       // unknown
-        proposer_id: [0u8; 16],
-        system_id: 0,
-        ztli: swh.timelineid.unwrap(),
-        tenant_id: swh.tenantid.unwrap(),
-        tli: 0,
-        wal_seg_size: pg_constants::WAL_SEGMENT_SIZE as u32, // 16MB, default for tests
-    });
-
-    let response = swh.timeline.get().process_msg(&greeting_request)?;
-    match response {
-        AcceptorProposerMessage::Greeting(_) => Ok(()),
-        _ => anyhow::bail!("not GreetingResponse"),
-    }
-}
-
-#[derive(Serialize, Deserialize)]
-struct InsertedWAL {
-    begin_lsn: Lsn,
-    end_lsn: Lsn,
-    append_response: AppendResponse,
-}
-
-/// Extend local WAL with new LogicalMessage record. To do that,
-/// create AppendRequest with new WAL and pass it to safekeeper.
-fn append_logical_message(
-    swh: &mut SendWalHandler,
-    msg: AppendLogicalMessage,
-) -> Result<InsertedWAL> {
-    let wal_data = encode_logical_message(msg.lm_prefix, msg.lm_message);
-    let sk_state = swh.timeline.get().get_info();
-
-    let begin_lsn = msg.begin_lsn;
-    let end_lsn = begin_lsn + wal_data.len() as u64;
-
-    let commit_lsn = if msg.set_commit_lsn {
-        end_lsn
-    } else {
-        sk_state.commit_lsn
-    };
-
-    let append_request = ProposerAcceptorMessage::AppendRequest(AppendRequest {
-        h: AppendRequestHeader {
-            term: msg.term,
-            epoch_start_lsn: begin_lsn,
-            begin_lsn,
-            end_lsn,
-            commit_lsn,
-            truncate_lsn: msg.truncate_lsn,
-            proposer_uuid: [0u8; 16],
-        },
-        wal_data: Bytes::from(wal_data),
-    });
-
-    let response = swh.timeline.get().process_msg(&append_request)?;
-
-    let append_response = match response {
-        AcceptorProposerMessage::AppendResponse(resp) => resp,
-        _ => anyhow::bail!("not AppendResponse"),
-    };
-
-    Ok(InsertedWAL {
-        begin_lsn,
-        end_lsn,
-        append_response,
-    })
-}
-
-#[repr(C)]
-#[derive(Debug, Clone, Default, Serialize, Deserialize)]
-struct XlLogicalMessage {
-    db_id: Oid,
-    transactional: uint32, // bool, takes 4 bytes due to alignment in C structures
-    prefix_size: uint64,
-    message_size: uint64,
-}
-
-impl XlLogicalMessage {
-    pub fn encode(&self) -> Bytes {
-        use zenith_utils::bin_ser::LeSer;
-        self.ser().unwrap().into()
-    }
-}
-
-/// Create new WAL record for non-transactional logical message.
-/// Used for creating artificial WAL for tests, as LogicalMessage
-/// record is basically no-op.
-fn encode_logical_message(prefix: String, message: String) -> Vec<u8> {
-    let mut prefix_bytes = BytesMut::with_capacity(prefix.len() + 1);
-    prefix_bytes.put(prefix.as_bytes());
-    prefix_bytes.put_u8(0);
-
-    let message_bytes = message.as_bytes();
-
-    let logical_message = XlLogicalMessage {
-        db_id: 0,
-        transactional: 0,
-        prefix_size: prefix_bytes.len() as u64,
-        message_size: message_bytes.len() as u64,
-    };
-
-    let mainrdata = logical_message.encode();
-    let mainrdata_len: usize = mainrdata.len() + prefix_bytes.len() + message_bytes.len();
-    // only short mainrdata is supported for now
-    assert!(mainrdata_len <= 255);
-    let mainrdata_len = mainrdata_len as u8;
-
-    let mut data: Vec<u8> = vec![pg_constants::XLR_BLOCK_ID_DATA_SHORT, mainrdata_len];
-    data.extend_from_slice(&mainrdata);
-    data.extend_from_slice(&prefix_bytes);
-    data.extend_from_slice(message_bytes);
-
-    let total_len = xlog_utils::XLOG_SIZE_OF_XLOG_RECORD + data.len();
-
-    let mut header = XLogRecord {
-        xl_tot_len: total_len as u32,
-        xl_xid: 0,
-        xl_prev: 0,
-        xl_info: 0,
-        xl_rmid: 21,
-        __bindgen_padding_0: [0u8; 2usize],
-        xl_crc: 0, // crc will be calculated later
-    };
-
-    let header_bytes = header.encode();
-    let crc = crc32c_append(0, &data);
-    let crc = crc32c_append(crc, &header_bytes[0..xlog_utils::XLOG_RECORD_CRC_OFFS]);
-    header.xl_crc = crc;
-
-    let mut wal: Vec<u8> = Vec::new();
-    wal.extend_from_slice(&header.encode());
-    wal.extend_from_slice(&data);
-
-    // WAL start position must be aligned at 8 bytes,
-    // this will add padding for the next WAL record.
-    const PADDING: usize = 8;
-    let padding_rem = wal.len() % PADDING;
-    if padding_rem != 0 {
-        wal.resize(wal.len() + PADDING - padding_rem, 0);
-    }
-
-    wal
-}
-
-#[test]
-fn test_encode_logical_message() {
-    let expected = [
-        64, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 21, 0, 0, 170, 34, 166, 227, 255, 38,
-        0, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 7, 0, 0, 0, 0, 0, 0, 0, 112, 114, 101, 102,
-        105, 120, 0, 109, 101, 115, 115, 97, 103, 101,
-    ];
-    let actual = encode_logical_message("prefix".to_string(), "message".to_string());
-    assert_eq!(expected, actual[..]);
-}
--- a/walkeeper/src/lib.rs
+++ b/walkeeper/src/lib.rs
@@ -2,7 +2,6 @@
 use std::path::PathBuf;
 use std::time::Duration;

-pub mod json_ctrl;
 pub mod receive_wal;
 pub mod replication;
 pub mod s3_offload;
--- a/walkeeper/src/receive_wal.rs
+++ b/walkeeper/src/receive_wal.rs
@@ -74,7 +74,7 @@ fn request_callback(conf: WalAcceptorConf, timelineid: ZTimelineId, tenantid: ZT

 impl<'pg> ReceiveWalConn<'pg> {
    pub fn new(pg: &'pg mut PostgresBackend) -> Result<ReceiveWalConn<'pg>> {
-        let peer_addr = *pg.get_peer_addr();
+        let peer_addr = pg.get_peer_addr().clone();
        Ok(ReceiveWalConn {
            pg_backend: pg,
            peer_addr,
--- a/walkeeper/src/replication.rs
+++ b/walkeeper/src/replication.rs
@@ -3,7 +3,7 @@

 use crate::send_wal::SendWalHandler;
 use crate::timeline::{Timeline, TimelineTools};
-use anyhow::{anyhow, Context, Result};
+use anyhow::{anyhow, Result};
 use bytes::Bytes;
 use log::*;
 use postgres_ffi::xlog_utils::{get_current_timestamp, TimestampTz, XLogFileName, MAX_SEND_SIZE};
@@ -25,10 +25,6 @@ use zenith_utils::sock_split::ReadStream;

 pub const END_REPLICATION_MARKER: Lsn = Lsn::MAX;

-// See: https://www.postgresql.org/docs/13/protocol-replication.html
-const HOT_STANDBY_FEEDBACK_TAG_BYTE: u8 = b'h';
-const STANDBY_STATUS_UPDATE_TAG_BYTE: u8 = b'r';
-
 type FullTransactionId = u64;

 /// Hot standby feedback received from replica
@@ -85,22 +81,10 @@ impl ReplicationConn {
    ) -> Result<()> {
        // Wait for replica's feedback.
        while let Some(msg) = FeMessage::read(&mut stream_in)? {
-            match &msg {
+            match msg {
                FeMessage::CopyData(m) => {
-                    // There's two possible data messages that the client is supposed to send here:
-                    // `HotStandbyFeedback` and `StandbyStatusUpdate`. We only handle hot standby
-                    // feedback.
-
-                    match m.first().cloned() {
-                        Some(HOT_STANDBY_FEEDBACK_TAG_BYTE) => {
-                            // Note: deserializing is on m[1..] because we skip the tag byte.
-                            let feedback = HotStandbyFeedback::des(&m[1..])
-                                .context("failed to deserialize HotStandbyFeedback")?;
-                            subscriber.add_hs_feedback(feedback);
-                        }
-                        Some(STANDBY_STATUS_UPDATE_TAG_BYTE) => (),
-                        _ => warn!("unexpected message {:?}", msg),
-                    }
+                    let feedback = HotStandbyFeedback::des(&m)?;
+                    subscriber.add_hs_feedback(feedback);
                }
                FeMessage::Sync => {}
                FeMessage::CopyFail => return Err(anyhow!("Copy failed")),
@@ -121,7 +105,7 @@ impl ReplicationConn {
        let mut lsns = caps.map(|cap| cap[1].parse::<Lsn>());
        let start_pos = lsns
            .next()
-            .ok_or_else(|| anyhow!("Failed to parse start LSN from command"))??;
+            .ok_or_else(|| anyhow!("failed to find start LSN"))??;
        let stop_pos = lsns.next().transpose()?.unwrap_or(Lsn(0));
        Ok((start_pos, stop_pos))
    }
@@ -136,12 +120,13 @@ impl ReplicationConn {
        }

        // If that failed, try it without the .partial extension.
-        File::open(&wal_file_path)
-            .with_context(|| format!("Failed to open WAL file {:?}", wal_file_path))
-            .map_err(|e| {
-                error!("{}", e);
-                e
-            })
+        match File::open(&wal_file_path) {
+            Ok(opened_file) => Ok(opened_file),
+            Err(e) => {
+                error!("Failed to open log file {:?}: {}", &wal_file_path, e);
+                Err(e.into())
+            }
+        }
    }

    ///
@@ -159,17 +144,17 @@ impl ReplicationConn {

        thread::spawn(move || {
            if let Err(err) = Self::background_thread(bg_stream_in, bg_timeline) {
-                error!("Replication background thread failed: {}", err);
+                error!("socket error: {}", err);
            }
        });

-        let (mut start_pos, mut stop_pos) = Self::parse_start_stop(cmd)?;
+        let (mut start_pos, mut stop_pos) = Self::parse_start_stop(&cmd)?;

        let mut wal_seg_size: usize;
        loop {
            wal_seg_size = swh.timeline.get().get_info().server.wal_seg_size as usize;
            if wal_seg_size == 0 {
-                error!("Cannot start replication before connecting to wal_proposer");
+                error!("Can not start replication before connecting to wal_proposer");
                sleep(Duration::from_secs(1));
            } else {
                break;
@@ -231,9 +216,8 @@ impl ReplicationConn {

            // Read some data from the file.
            let mut file_buf = vec![0u8; send_size];
-            file.seek(SeekFrom::Start(xlogoff as u64))
-                .and_then(|_| file.read_exact(&mut file_buf))
-                .context("Failed to read data from WAL file")?;
+            file.seek(SeekFrom::Start(xlogoff as u64))?;
+            file.read_exact(&mut file_buf)?;

            // Write some data to the network socket.
            pgb.write_message(&BeMessage::XLogData(XLogDataBody {
@@ -241,12 +225,11 @@ impl ReplicationConn {
                wal_end: end_pos.0,
                timestamp: get_current_timestamp(),
                data: &file_buf,
-            }))
-            .context("Failed to send XLogData")?;
+            }))?;

            start_pos += send_size as u64;

-            debug!("sent WAL up to {}", end_pos);
+            debug!("Sent WAL to page server up to {}", end_pos);

            // Decide whether to reuse this file. If we don't set wal_file here
            // a new file will be opened next time.
--- a/walkeeper/src/safekeeper.rs
+++ b/walkeeper/src/safekeeper.rs
@@ -7,11 +7,9 @@ use byteorder::WriteBytesExt;
 use bytes::Buf;
 use bytes::Bytes;
 use log::*;
-use pageserver::waldecoder::WalStreamDecoder;
 use postgres_ffi::xlog_utils::TimeLineID;
 use serde::{Deserialize, Serialize};
 use std::cmp::max;
-use std::cmp::min;
 use std::io;
 use std::io::Read;

@@ -28,7 +26,7 @@ const SK_PROTOCOL_VERSION: u32 = 1;
 const UNKNOWN_SERVER_VERSION: u32 = 0;

 /// Consensus logical timestamp.
-pub type Term = u64;
+type Term = u64;

 /// Unique id of proposer. Not needed for correctness, used for monitoring.
 type PgUuid = [u8; 16];
@@ -49,7 +47,6 @@ pub struct ServerInfo {
    /// Postgres server version
    pub pg_version: u32,
    pub system_id: SystemId,
-    pub tenant_id: ZTenantId,
    /// Zenith timelineid
    pub ztli: ZTimelineId,
    pub tli: TimeLineID,
@@ -68,16 +65,14 @@ pub struct SafeKeeperState {
    /// information about server
    pub server: ServerInfo,
    /// Unique id of the last *elected* proposer we dealed with. Not needed
-    /// for correctness, exists for monitoring purposes.
+    /// correctness, exists for monitoring purposes.
    pub proposer_uuid: PgUuid,
-    /// part of WAL acknowledged by quorum and available locally
+    /// part of WAL acknowledged by quorum (note that we might not have wal to
+    /// up this point locally)
    pub commit_lsn: Lsn,
-    /// minimal LSN which may be needed for recovery of some safekeeper (end_lsn
-    /// of last record streamed to everyone)
+    /// minimal LSN which may be needed for recovery of some safekeeper (end lsn
+    /// + 1 of last record streamed to everyone)
    pub truncate_lsn: Lsn,
-    // Safekeeper starts receiving WAL from this LSN, zeros before it ought to
-    // be skipped during decoding.
-    pub wal_start_lsn: Lsn,
 }

 impl SafeKeeperState {
@@ -89,7 +84,6 @@ impl SafeKeeperState {
            server: ServerInfo {
                pg_version: UNKNOWN_SERVER_VERSION, /* Postgres server version */
                system_id: 0,                       /* Postgres system identifier */
-                tenant_id: ZTenantId::from([0u8; 16]),
                ztli: ZTimelineId::from([0u8; 16]),
                tli: 0,
                wal_seg_size: 0,
@@ -97,21 +91,14 @@ impl SafeKeeperState {
            proposer_uuid: [0; 16],
            commit_lsn: Lsn(0),   /* part of WAL acknowledged by quorum */
            truncate_lsn: Lsn(0), /* minimal LSN which may be needed for recovery of some safekeeper */
-            wal_start_lsn: Lsn(0),
        }
    }
 }

-impl Default for SafeKeeperState {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
 // protocol messages

 /// Initial Proposer -> Acceptor message
-#[derive(Debug, Deserialize)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct ProposerGreeting {
    /// proposer-acceptor protocol version
    pub protocol_version: u32,
@@ -128,50 +115,50 @@ pub struct ProposerGreeting {

 /// Acceptor -> Proposer initial response: the highest term known to me
 /// (acceptor voted for).
-#[derive(Debug, Serialize)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct AcceptorGreeting {
    term: u64,
 }

 /// Vote request sent from proposer to safekeepers
-#[derive(Debug, Deserialize)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct VoteRequest {
    term: Term,
 }

 /// Vote itself, sent from safekeeper to proposer
-#[derive(Debug, Serialize)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct VoteResponse {
    term: Term,      // not really needed, just a sanity check
    vote_given: u64, // fixme u64 due to padding
    /// Safekeeper's log position, to let proposer choose the most advanced one
    epoch: Term,
    flush_lsn: Lsn,
-    truncate_lsn: Lsn,
+    restart_lsn: Lsn,
 }

 /// Request with WAL message sent from proposer to safekeeper. Along the way it
 /// announces 1) successful election (with epoch_start_lsn); 2) commit_lsn.
-#[derive(Debug)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct AppendRequest {
-    pub h: AppendRequestHeader,
-    pub wal_data: Bytes,
+    h: AppendRequestHeader,
+    wal_data: Bytes,
 }
-#[derive(Debug, Clone, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AppendRequestHeader {
-    pub term: Term,
+    term: Term,
    // LSN since the proposer appends WAL; determines epoch switch point.
-    pub epoch_start_lsn: Lsn,
+    epoch_start_lsn: Lsn,
    /// start position of message in WAL
-    pub begin_lsn: Lsn,
+    begin_lsn: Lsn,
    /// end position of message in WAL
-    pub end_lsn: Lsn,
+    end_lsn: Lsn,
    /// LSN committed by quorum of safekeepers
-    pub commit_lsn: Lsn,
-    /// minimal LSN which may be needed by proposer to perform recovery of some safekeeper
-    pub truncate_lsn: Lsn,
+    commit_lsn: Lsn,
+    /// restart LSN position  (minimal LSN which may be needed by proposer to perform recovery)
+    restart_lsn: Lsn,
    // only for logging/debugging
-    pub proposer_uuid: PgUuid,
+    proposer_uuid: PgUuid,
 }

 /// Report safekeeper state to proposer
@@ -185,9 +172,6 @@ pub struct AppendResponse {
    // make much sense without taking epoch into account, as history can be
    // diverged.
    pub flush_lsn: Lsn,
-    // We report back our awareness about which WAL is committed, as this is
-    // a criterion for walproposer --sync mode exit
-    pub commit_lsn: Lsn,
    pub hs_feedback: HotStandbyFeedback,
 }

@@ -221,7 +205,7 @@ impl ProposerAcceptorMessage {
                let rec_size = hdr
                    .end_lsn
                    .checked_sub(hdr.begin_lsn)
-                    .ok_or_else(|| anyhow!("begin_lsn > end_lsn in AppendRequest"))?
+                    .ok_or(anyhow!("begin_lsn > end_lsn in AppendRequest"))?
                    .0 as usize;
                if rec_size > MAX_SEND_SIZE {
                    bail!(
@@ -233,7 +217,10 @@ impl ProposerAcceptorMessage {
                let mut wal_data_vec: Vec<u8> = vec![0; rec_size];
                stream.read_exact(&mut wal_data_vec)?;
                let wal_data = Bytes::from(wal_data_vec);
-                let msg = AppendRequest { h: hdr, wal_data };
+                let msg = AppendRequest {
+                    h: hdr,
+                    wal_data: wal_data,
+                };

                Ok(ProposerAcceptorMessage::AppendRequest(msg))
            }
@@ -281,18 +268,16 @@ pub trait Storage {

 /// SafeKeeper which consumes events (messages from compute) and provides
 /// replies.
+#[derive(Debug)]
 pub struct SafeKeeper<ST: Storage> {
-    /// Locally flushed part of WAL with full records (end_lsn of last record).
-    /// Established by reading wal.
+    /// Locally flushed part of WAL (end_lsn of last record). Established by
+    /// reading wal.
    pub flush_lsn: Lsn,
    pub tli: u32,
-    /// not-yet-flushed pairs of same named fields in s.*
-    pub commit_lsn: Lsn,
-    pub truncate_lsn: Lsn,
+    pub flushed_truncate_lsn: Lsn,
    pub storage: ST,
    pub s: SafeKeeperState,          // persistent part
    pub elected_proposer_term: Term, // for monitoring/debugging
-    decoder: WalStreamDecoder,
 }

 impl<ST> SafeKeeper<ST>
@@ -304,12 +289,10 @@ where
        SafeKeeper {
            flush_lsn,
            tli,
-            commit_lsn: state.commit_lsn,
-            truncate_lsn: state.truncate_lsn,
+            flushed_truncate_lsn: Lsn(0),
            storage,
            s: state,
            elected_proposer_term: 0,
-            decoder: WalStreamDecoder::new(Lsn(0)),
        }
    }

@@ -337,6 +320,13 @@ where
                SK_PROTOCOL_VERSION
            );
        }
+        if self.s.server.system_id != 0 && self.s.server.system_id != msg.system_id {
+            bail!(
+                "system identifier changed: got {}, expected {}",
+                msg.system_id,
+                self.s.server.system_id,
+            );
+        }
        /* Postgres upgrade is not treated as fatal error */
        if msg.pg_version != self.s.server.pg_version
            && self.s.server.pg_version != UNKNOWN_SERVER_VERSION
@@ -349,10 +339,10 @@ where

        // set basic info about server, if not yet
        self.s.server.system_id = msg.system_id;
-        self.s.server.tenant_id = msg.tenant_id;
        self.s.server.ztli = msg.ztli;
        self.s.server.tli = msg.tli;
        self.s.server.wal_seg_size = msg.wal_seg_size;
+        self.s.proposer_uuid = msg.proposer_id;
        self.storage.persist(&self.s, true)?;

        info!(
@@ -372,7 +362,7 @@ where
            vote_given: false as u64,
            epoch: 0,
            flush_lsn: Lsn(0),
-            truncate_lsn: Lsn(0),
+            restart_lsn: Lsn(0),
        };
        if self.s.acceptor_state.term < msg.term {
            self.s.acceptor_state.term = msg.term;
@@ -381,20 +371,19 @@ where
            resp.vote_given = true as u64;
            resp.epoch = self.s.acceptor_state.epoch;
            resp.flush_lsn = self.flush_lsn;
-            resp.truncate_lsn = self.s.truncate_lsn;
+            resp.restart_lsn = self.s.truncate_lsn;
        }
        info!("processed VoteRequest for term {}: {:?}", msg.term, &resp);
        Ok(AcceptorProposerMessage::VoteResponse(resp))
    }

    /// Handle request to append WAL.
-    #[allow(clippy::comparison_chain)]
    fn handle_append_request(&mut self, msg: &AppendRequest) -> Result<AcceptorProposerMessage> {
        // log first AppendRequest from this proposer
        if self.elected_proposer_term < msg.h.term {
            info!(
-                "start accepting WAL from timeline {}, tenant {}, term {}, epochStartLsn {:?}",
-                self.s.server.ztli, self.s.server.tenant_id, msg.h.term, msg.h.epoch_start_lsn,
+                "start receiving WAL from timeline {} term {}",
+                self.s.server.ztli, msg.h.term,
            );
            self.elected_proposer_term = msg.h.term;
        }
@@ -409,122 +398,62 @@ where
            let resp = AppendResponse {
                term: self.s.acceptor_state.term,
                epoch: self.s.acceptor_state.epoch,
-                commit_lsn: Lsn(0),
                flush_lsn: Lsn(0),
                hs_feedback: HotStandbyFeedback::empty(),
            };
            return Ok(AcceptorProposerMessage::AppendResponse(resp));
        }

-        self.s.proposer_uuid = msg.h.proposer_uuid;
-        let mut sync_control_file = false;
-
        // do the job
-        let mut last_rec_lsn = Lsn(0);
-        if !msg.wal_data.is_empty() {
-            self.storage
-                .write_wal(&self.s, msg.h.begin_lsn, &msg.wal_data)?;
-
-            // figure out last record's end lsn for reporting (if we got the
-            // whole record)
-            if self.decoder.available() != msg.h.begin_lsn {
-                info!(
-                    "restart decoder from {} to {}",
-                    self.decoder.available(),
-                    msg.h.begin_lsn,
-                );
-                self.decoder = WalStreamDecoder::new(msg.h.begin_lsn);
-            }
-            self.decoder.feed_bytes(&msg.wal_data);
-            loop {
-                match self.decoder.poll_decode()? {
-                    None => break, // no full record yet
-                    Some((lsn, _rec)) => {
-                        last_rec_lsn = lsn;
-                    }
-                }
-            }
-
-            // If this was the first record we ever receieved, remember LSN to help
-            // find_end_of_wal skip the hole in the beginning.
-            if self.s.wal_start_lsn == Lsn(0) {
-                self.s.wal_start_lsn = msg.h.begin_lsn;
-                sync_control_file = true;
-            }
-        }
-
+        self.storage
+            .write_wal(&self.s, msg.h.begin_lsn, &msg.wal_data)?;
+        let mut sync_control_file = false;
        /*
         * Epoch switch happen when written WAL record cross the boundary.
         * The boundary is maximum of last WAL position at this node (FlushLSN) and global
         * maximum (vcl) determined by WAL proposer during handshake.
         * Switching epoch means that node completes recovery and start writing in the WAL new data.
         * XXX: this is wrong, we must actively truncate not matching part of log.
-         *
-         * The non-strict inequality is important for us, as proposer in --sync mode doesn't
-         * generate new records, but to advance commit_lsn epoch switch must happen on majority.
-         * We can regard this as commit of empty entry in new epoch, this should be safe.
         */
        if self.s.acceptor_state.epoch < msg.h.term
-            && msg.h.end_lsn >= max(self.flush_lsn, msg.h.epoch_start_lsn)
+            && msg.h.end_lsn > max(self.flush_lsn, msg.h.epoch_start_lsn)
        {
-            info!(
-                "switched to new epoch {} on receival of request end_lsn={:?}, len={:?}",
-                msg.h.term,
-                msg.h.end_lsn,
-                msg.wal_data.len(),
-            );
+            info!("switched to new epoch {}", msg.h.term);
            self.s.acceptor_state.epoch = msg.h.term; /* bump epoch */
            sync_control_file = true;
        }
-        if last_rec_lsn > self.flush_lsn {
-            self.flush_lsn = last_rec_lsn;
+        if msg.h.end_lsn > self.flush_lsn {
+            self.flush_lsn = msg.h.end_lsn;
        }

-        // Advance commit_lsn taking into account what we have locally. xxx this
-        // is wrapped into epoch check because we overwrite wal instead of
-        // truncating it, so without it commit_lsn might include wrong part.
-        // Anyway, nobody is much interested in our commit_lsn while epoch
-        // switch hasn't happened, right?
-        //
-        // commit_lsn can be 0, being unknown to new walproposer while he hasn't
-        // collected majority of its epoch acks yet, ignore it in this case.
-        if self.s.acceptor_state.epoch == msg.h.term && msg.h.commit_lsn != Lsn(0) {
-            let commit_lsn = min(msg.h.commit_lsn, self.flush_lsn);
-            // If new commit_lsn reached epoch switch, force sync of control file:
-            // walproposer in sync mode is very interested when this happens.
-            sync_control_file |=
-                commit_lsn >= msg.h.epoch_start_lsn && self.s.commit_lsn < msg.h.epoch_start_lsn;
-            self.commit_lsn = commit_lsn;
-        }
+        self.s.proposer_uuid = msg.h.proposer_uuid;
+        self.s.commit_lsn = msg.h.commit_lsn;
+        self.s.truncate_lsn = msg.h.restart_lsn;

-        self.truncate_lsn = msg.h.truncate_lsn;
        /*
-         * Update truncate and commit LSN in control file.
+         * Update restart LSN in control file.
         * To avoid negative impact on performance of extra fsync, do it only
         * when restart_lsn delta exceeds WAL segment size.
         */
        sync_control_file |=
-            self.s.truncate_lsn + (self.s.server.wal_seg_size as u64) < self.truncate_lsn;
-        if sync_control_file {
-            self.s.commit_lsn = self.commit_lsn;
-            self.s.truncate_lsn = self.truncate_lsn;
-        }
+            self.flushed_truncate_lsn + (self.s.server.wal_seg_size as u64) < self.s.truncate_lsn;
        self.storage.persist(&self.s, sync_control_file)?;
+        if sync_control_file {
+            self.flushed_truncate_lsn = self.s.truncate_lsn;
+        }

        let resp = AppendResponse {
            term: self.s.acceptor_state.term,
            epoch: self.s.acceptor_state.epoch,
            flush_lsn: self.flush_lsn,
-            commit_lsn: self.s.commit_lsn,
            // will be filled by caller code to avoid bothering safekeeper
            hs_feedback: HotStandbyFeedback::empty(),
        };
-        info!(
-            "processed AppendRequest of len {}, end_lsn={:?}, commit_lsn={:?}, truncate_lsn={:?}, resp {:?}",
+        trace!(
+            "processed AppendRequest of len {}, flush_lsn={:X}/{:>08X}, resp {:?}",
            msg.wal_data.len(),
-            msg.h.end_lsn,
-            msg.h.commit_lsn,
-            msg.h.truncate_lsn,
+            (self.flush_lsn.0 >> 32) as u32,
+            self.flush_lsn.0 as u32,
            &resp,
        );
        Ok(AcceptorProposerMessage::AppendResponse(resp))
@@ -563,7 +492,7 @@ mod tests {
        let mut vote_resp = sk.process_msg(&vote_request);
        match vote_resp.unwrap() {
            AcceptorProposerMessage::VoteResponse(resp) => assert!(resp.vote_given != 0),
-            r => panic!("unexpected response: {:?}", r),
+            _ => assert!(false),
        }

        // reboot...
@@ -577,7 +506,7 @@ mod tests {
        vote_resp = sk.process_msg(&vote_request);
        match vote_resp.unwrap() {
            AcceptorProposerMessage::VoteResponse(resp) => assert!(resp.vote_given == 0),
-            r => panic!("unexpected response: {:?}", r),
+            _ => assert!(false),
        }
    }

@@ -590,11 +519,11 @@ mod tests {

        let mut ar_hdr = AppendRequestHeader {
            term: 1,
-            epoch_start_lsn: Lsn(3),
+            epoch_start_lsn: Lsn(2),
            begin_lsn: Lsn(1),
            end_lsn: Lsn(2),
            commit_lsn: Lsn(0),
-            truncate_lsn: Lsn(0),
+            restart_lsn: Lsn(0),
            proposer_uuid: [0; 16],
        };
        let mut append_request = AppendRequest {
@@ -602,20 +531,20 @@ mod tests {
            wal_data: Bytes::from_static(b"b"),
        };

-        // check that AppendRequest before epochStartLsn doesn't switch epoch
+        // check that AppendRequest before VCL doesn't switch epoch
        let resp = sk.process_msg(&ProposerAcceptorMessage::AppendRequest(append_request));
        assert!(resp.is_ok());
-        assert_eq!(sk.storage.persisted_state.acceptor_state.epoch, 0);
+        assert!(sk.storage.persisted_state.acceptor_state.epoch == 0);

-        // but record at epochStartLsn does the switch
+        // but record after VCL does the switch
        ar_hdr.begin_lsn = Lsn(2);
        ar_hdr.end_lsn = Lsn(3);
        append_request = AppendRequest {
-            h: ar_hdr,
+            h: ar_hdr.clone(),
            wal_data: Bytes::from_static(b"b"),
        };
        let resp = sk.process_msg(&ProposerAcceptorMessage::AppendRequest(append_request));
        assert!(resp.is_ok());
-        assert_eq!(sk.storage.persisted_state.acceptor_state.epoch, 1);
+        assert!(sk.storage.persisted_state.acceptor_state.epoch == 1);
    }
 }
--- a/walkeeper/src/send_wal.rs
+++ b/walkeeper/src/send_wal.rs
@@ -2,7 +2,6 @@
 //! pageserver/any other consumer.
 //!

-use crate::json_ctrl::handle_json_ctrl;
 use crate::receive_wal::ReceiveWalConn;
 use crate::replication::ReplicationConn;
 use crate::timeline::{Timeline, TimelineTools};
@@ -34,13 +33,13 @@ impl postgres_backend::Handler for SendWalHandler {
        let ztimelineid = sm
            .params
            .get("ztimelineid")
-            .ok_or_else(|| anyhow!("timelineid is required"))?;
+            .ok_or(anyhow!("timelineid is required"))?;
        self.timelineid = Some(ZTimelineId::from_str(ztimelineid)?);

        let ztenantid = sm
            .params
            .get("ztenantid")
-            .ok_or_else(|| anyhow!("tenantid is required"))?;
+            .ok_or(anyhow!("tenantid is required"))?;
        self.tenantid = Some(ZTenantId::from_str(ztenantid)?);

        if let Some(app_name) = sm.params.get("application_name") {
@@ -50,11 +49,9 @@ impl postgres_backend::Handler for SendWalHandler {
    }

    fn process_query(&mut self, pgb: &mut PostgresBackend, query_string: Bytes) -> Result<()> {
-        // START_WAL_PUSH is the only command that initializes the timeline in production.
-        // There is also JSON_CTRL command, which should initialize the timeline for testing.
+        // START_WAL_PUSH is the only command that initializes the timeline
        if self.timeline.is_none() {
-            if query_string.starts_with(b"START_WAL_PUSH") || query_string.starts_with(b"JSON_CTRL")
-            {
+            if query_string.starts_with(b"START_WAL_PUSH") {
                self.timeline.set(
                    &self.conf,
                    self.tenantid.unwrap(),
@@ -79,9 +76,6 @@ impl postgres_backend::Handler for SendWalHandler {
        } else if query_string.starts_with(b"START_WAL_PUSH") {
            ReceiveWalConn::new(pgb)?.run(self)?;
            Ok(())
-        } else if query_string.starts_with(b"JSON_CTRL") {
-            handle_json_ctrl(self, pgb, &query_string)?;
-            Ok(())
        } else {
            bail!("Unexpected command {:?}", query_string);
        }
--- a/walkeeper/src/timeline.rs
+++ b/walkeeper/src/timeline.rs
@@ -27,9 +27,12 @@ use postgres_ffi::xlog_utils::{XLogFileName, XLOG_BLCKSZ};
 const CONTROL_FILE_NAME: &str = "safekeeper.control";

 /// Shared state associated with database instance (tenant)
+#[derive(Debug)]
 struct SharedState {
    /// Safekeeper object
    sk: SafeKeeper<FileStorage>,
+    /// opened file control file handle (needed to hold exlusive file lock)
+    control_file: File,
    /// For receiving-sending wal cooperation
    /// quorum commit LSN we've notified walsenders about
    commit_lsn: Lsn,
@@ -56,17 +59,12 @@ impl SharedState {
    ) -> Result<Self> {
        let (cf, state) = SharedState::load_control_file(conf, timelineid, create)?;
        let storage = FileStorage {
-            control_file: cf,
+            control_file: cf.try_clone()?,
            conf: conf.clone(),
        };
        let (flush_lsn, tli) = if state.server.wal_seg_size != 0 {
            let wal_dir = conf.data_dir.join(format!("{}", timelineid));
-            find_end_of_wal(
-                &wal_dir,
-                state.server.wal_seg_size as usize,
-                true,
-                state.wal_start_lsn,
-            )?
+            find_end_of_wal(&wal_dir, state.server.wal_seg_size as usize, true)
        } else {
            (0, 0)
        };
@@ -74,6 +72,7 @@ impl SharedState {
        Ok(Self {
            commit_lsn: Lsn(0),
            sk: SafeKeeper::new(Lsn(flush_lsn), tli, storage, state),
+            control_file: cf,
            hs_feedback: HotStandbyFeedback {
                ts: 0,
                xmin: u64::MAX,
@@ -128,7 +127,7 @@ impl SharedState {
                    if let CreateControlFile::False = create {
                        bail!("control file is empty");
                    }
-                    Ok((file, SafeKeeperState::new()))
+                    return Ok((file, SafeKeeperState::new()));
                } else {
                    match SafeKeeperState::des_from(&mut file) {
                        Err(e) => {
@@ -145,7 +144,7 @@ impl SharedState {
                                    SK_FORMAT_VERSION
                                );
                            }
-                            Ok((file, s))
+                            return Ok((file, s));
                        }
                    }
                }
@@ -162,6 +161,7 @@ impl SharedState {
 }

 /// Database instance (tenant)
+#[derive(Debug)]
 pub struct Timeline {
    pub timelineid: ZTimelineId,
    mutex: Mutex<SharedState>,
@@ -217,11 +217,14 @@ impl Timeline {
            rmsg = shared_state.sk.process_msg(msg)?;
            // locally available commit lsn. flush_lsn can be smaller than
            // commit_lsn if we are catching up safekeeper.
-            commit_lsn = shared_state.sk.commit_lsn;
+            commit_lsn = min(shared_state.sk.flush_lsn, shared_state.sk.s.commit_lsn);

            // if this is AppendResponse, fill in proper hot standby feedback
-            if let AcceptorProposerMessage::AppendResponse(ref mut resp) = rmsg {
-                resp.hs_feedback = shared_state.hs_feedback.clone();
+            match rmsg {
+                AcceptorProposerMessage::AppendResponse(ref mut resp) => {
+                    resp.hs_feedback = shared_state.hs_feedback.clone();
+                }
+                _ => (),
            }
        }
        // Ping wal sender that new data might be available.
@@ -398,7 +401,7 @@ impl Storage for FileStorage {
                    {
                        Ok(mut file) => {
                            for _ in 0..(wal_seg_size / XLOG_BLCKSZ) {
-                                file.write_all(ZERO_BLOCK)?;
+                                file.write_all(&ZERO_BLOCK)?;
                            }
                            wal_file = file;
                        }
--- a/zenith/src/main.rs
+++ b/zenith/src/main.rs
@@ -1,10 +1,10 @@
-use anyhow::anyhow;
+use anyhow::{anyhow, bail};
 use anyhow::{Context, Result};
 use clap::{App, AppSettings, Arg, ArgMatches, SubCommand};
 use control_plane::compute::ComputeControlPlane;
-use control_plane::local_env;
+use control_plane::local_env::{self, LocalEnv};
 use control_plane::storage::PageServerNode;
-use pageserver::defaults::{DEFAULT_HTTP_LISTEN_PORT, DEFAULT_PG_LISTEN_PORT};
+use std::collections::btree_map::Entry;
 use std::collections::HashMap;
 use std::process::exit;
 use std::str::FromStr;
@@ -13,6 +13,7 @@ use zenith_utils::postgres_backend::AuthType;
 use zenith_utils::zid::{ZTenantId, ZTimelineId};

 use pageserver::branches::BranchInfo;
+use zenith_utils::lsn::Lsn;

 ///
 /// Branches tree element used as a value in the HashMap.
@@ -29,7 +30,7 @@ struct BranchTreeEl {
 // This utility helps to manage zenith installation. That includes following:
 //   * Management of local postgres installations running on top of the
 //     pageserver.
-//   * Providing CLI api to the pageserver
+//   * Providing CLI api to the pageserver (local or remote)
 //   * TODO: export/import to/from usual postgres
 fn main() -> Result<()> {
    let timeline_arg = Arg::with_name("timeline")
@@ -44,27 +45,16 @@ fn main() -> Result<()> {
        .takes_value(true)
        .required(false);

-    let port_arg = Arg::with_name("port")
-        .long("port")
-        .required(false)
-        .value_name("port");
-
    let matches = App::new("Zenith CLI")
        .setting(AppSettings::ArgRequiredElseHelp)
        .subcommand(
            SubCommand::with_name("init")
                .about("Initialize a new Zenith repository")
                .arg(
-                    Arg::with_name("pageserver-pg-port")
-                        .long("pageserver-pg-port")
+                    Arg::with_name("remote-pageserver")
+                        .long("remote-pageserver")
                        .required(false)
-                        .value_name("pageserver-pg-port"),
-                )
-                .arg(
-                    Arg::with_name("pageserver-http-port")
-                        .long("pageserver-http-port")
-                        .required(false)
-                        .value_name("pageserver-http-port"),
+                        .value_name("pageserver-url"),
                )
                .arg(
                    Arg::with_name("enable-auth")
@@ -97,7 +87,7 @@ fn main() -> Result<()> {
                .subcommand(SubCommand::with_name("list").arg(tenantid_arg.clone()))
                .subcommand(SubCommand::with_name("create")
                    .about("Create a postgres compute node")
-                    .arg(timeline_arg.clone()).arg(tenantid_arg.clone()).arg(port_arg.clone())
+                    .arg(timeline_arg.clone()).arg(tenantid_arg.clone())
                    .arg(
                        Arg::with_name("config-only")
                            .help("Don't do basebackup, create compute node with only config files")
@@ -105,12 +95,8 @@ fn main() -> Result<()> {
                            .required(false)
                    ))
                .subcommand(SubCommand::with_name("start")
-                    .about("Start a postgres compute node.\n This command actually creates new node from scratch, but preserves existing config files")
-                    .arg(
-                        timeline_arg.clone()
-                    ).arg(
-                        tenantid_arg.clone()
-                    ).arg(port_arg.clone()))
+                    .about("Start a postrges compute node.\n This command actually creates new node from scrath, but preserves existing config files")
+                    .arg(timeline_arg.clone()).arg(tenantid_arg.clone()))
                .subcommand(
                    SubCommand::with_name("stop")
                        .arg(timeline_arg.clone())
@@ -121,36 +107,36 @@ fn main() -> Result<()> {
                                .long("destroy")
                                .required(false)
                        )
-                    )
-
+                )
+        )
+        .subcommand(
+            SubCommand::with_name("remote")
+                .setting(AppSettings::ArgRequiredElseHelp)
+                .about("Manage remote pagerservers")
+                .subcommand(
+                    SubCommand::with_name("add")
+                        .about("Add a new remote pageserver")
+                        .arg(Arg::with_name("name").required(true))
+                        .arg(
+                            Arg::with_name("url")
+                                .help("PostgreSQL connection URI")
+                                .required(true),
+                        ),
+                ),
        )
        .get_matches();

    // Create config file
    if let ("init", Some(init_match)) = matches.subcommand() {
        let tenantid = ZTenantId::generate();
-        let pageserver_pg_port = match init_match.value_of("pageserver-pg-port") {
-            Some(v) => v.parse()?,
-            None => DEFAULT_PG_LISTEN_PORT,
-        };
-        let pageserver_http_port = match init_match.value_of("pageserver-http-port") {
-            Some(v) => v.parse()?,
-            None => DEFAULT_HTTP_LISTEN_PORT,
-        };
-
+        let pageserver_uri = init_match.value_of("pageserver-url");
        let auth_type = if init_match.is_present("enable-auth") {
            AuthType::ZenithJWT
        } else {
            AuthType::Trust
        };
-
-        local_env::init(
-            pageserver_pg_port,
-            pageserver_http_port,
-            tenantid,
-            auth_type,
-        )
-        .with_context(|| "Failed to create config file")?;
+        local_env::init(pageserver_uri, tenantid, auth_type)
+            .with_context(|| "Failed to create config file")?;
    }

    // all other commands would need config
@@ -228,6 +214,13 @@ fn main() -> Result<()> {
            }
        }

+        ("remote", Some(remote_match)) => {
+            if let Err(e) = handle_remote(remote_match, &env) {
+                eprintln!("remote operation failed: {}", e);
+                exit(1);
+            }
+        }
+
        _ => {}
    };

@@ -366,7 +359,7 @@ fn get_branch_infos(
 }

 fn handle_tenant(tenant_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
-    let pageserver = PageServerNode::from_env(env);
+    let pageserver = PageServerNode::from_env(&env);
    match tenant_match.subcommand() {
        ("list", Some(_)) => {
            for tenant in pageserver.tenant_list()? {
@@ -388,19 +381,21 @@ fn handle_tenant(tenant_match: &ArgMatches, env: &local_env::LocalEnv) -> Result
 }

 fn handle_branch(branch_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
-    let pageserver = PageServerNode::from_env(env);
+    let pageserver = PageServerNode::from_env(&env);

    if let Some(branchname) = branch_match.value_of("branchname") {
        let startpoint_str = branch_match
            .value_of("start-point")
-            .ok_or_else(|| anyhow!("Missing start-point"))?;
+            .ok_or(anyhow!("Missing start-point"))?;
        let tenantid: ZTenantId = branch_match
            .value_of("tenantid")
            .map_or(Ok(env.tenantid), |value| value.parse())?;
        let branch = pageserver.branch_create(branchname, startpoint_str, &tenantid)?;
        println!(
            "Created branch '{}' at {:?} for tenant: {}",
-            branch.name, branch.latest_valid_lsn, tenantid,
+            branch.name,
+            branch.latest_valid_lsn.unwrap_or(Lsn(0)),
+            tenantid,
        );
    } else {
        let tenantid: ZTenantId = branch_match
@@ -439,7 +434,9 @@ fn handle_pg(pg_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
                    node.address,
                    branch_infos
                        .get(&node.timelineid)
-                        .map(|bi| bi.latest_valid_lsn.to_string())
+                        .map(|bi| bi
+                            .latest_valid_lsn
+                            .map_or("?".to_string(), |lsn| lsn.to_string()))
                        .unwrap_or_else(|| "?".to_string()),
                    node.status(),
                );
@@ -450,12 +447,9 @@ fn handle_pg(pg_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
                .value_of("tenantid")
                .map_or(Ok(env.tenantid), |value| value.parse())?;
            let timeline_name = create_match.value_of("timeline").unwrap_or("main");
+            let config_only = create_match.is_present("config-only");

-            let port: Option<u16> = match create_match.value_of("port") {
-                Some(p) => Some(p.parse()?),
-                None => None,
-            };
-            cplane.new_node(tenantid, timeline_name, port)?;
+            cplane.new_node(tenantid, timeline_name, config_only)?;
        }
        ("start", Some(start_match)) => {
            let tenantid: ZTenantId = start_match
@@ -463,11 +457,6 @@ fn handle_pg(pg_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
                .map_or(Ok(env.tenantid), |value| value.parse())?;
            let timeline_name = start_match.value_of("timeline").unwrap_or("main");

-            let port: Option<u16> = match start_match.value_of("port") {
-                Some(p) => Some(p.parse()?),
-                None => None,
-            };
-
            let node = cplane.nodes.get(&(tenantid, timeline_name.to_owned()));

            let auth_token = if matches!(env.auth_type, AuthType::ZenithJWT) {
@@ -477,20 +466,11 @@ fn handle_pg(pg_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
                None
            };

-            println!(
-                "Starting {} postgres on timeline {}...",
-                if node.is_some() { "existing" } else { "new" },
-                timeline_name
-            );
+            println!("Starting postgres on timeline {}...", timeline_name);
            if let Some(node) = node {
                node.start(&auth_token)?;
            } else {
-                // when used with custom port this results in non obvious behaviour
-                // port is remembered from first start command, i e
-                // start --port X
-                // stop
-                // start <-- will also use port X even without explicit port argument
-                let node = cplane.new_node(tenantid, timeline_name, port)?;
+                let node = cplane.new_node(tenantid, timeline_name, false)?;
                node.start(&auth_token)?;
            }
        }
@@ -513,3 +493,29 @@ fn handle_pg(pg_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {

    Ok(())
 }
+
+fn handle_remote(remote_match: &ArgMatches, local_env: &LocalEnv) -> Result<()> {
+    match remote_match.subcommand() {
+        ("add", Some(args)) => {
+            let name = args.value_of("name").unwrap();
+            let url = args.value_of("url").unwrap();
+
+            // validate the URL
+            postgres::Config::from_str(url)?;
+
+            let mut new_local_env = local_env.clone();
+
+            match new_local_env.remotes.entry(name.to_string()) {
+                Entry::Vacant(vacant) => {
+                    vacant.insert(url.to_string());
+                }
+                Entry::Occupied(_) => bail!("origin '{}' already exists", name),
+            }
+
+            local_env::save_config(&new_local_env)?;
+        }
+        _ => bail!("unknown command"),
+    }
+
+    Ok(())
+}
--- a/zenith_metrics/Cargo.toml
+++ b/zenith_metrics/Cargo.toml
@@ -4,6 +4,6 @@ version = "0.1.0"
 edition = "2018"

 [dependencies]
-prometheus = {version = "0.12", default_features=false} # removes protobuf dependency
+prometheus = "0.12"
 libc = "0.2"
 lazy_static = "1.4"
--- a/zenith_metrics/src/lib.rs
+++ b/zenith_metrics/src/lib.rs
@@ -13,6 +13,7 @@ pub use prometheus::{register_int_gauge_vec, IntGaugeVec};
 pub use prometheus::{Encoder, TextEncoder};

 mod wrappers;
+use libc::{c_long, getrusage, rusage, suseconds_t, time_t, timeval, RUSAGE_SELF};
 pub use wrappers::{CountedReader, CountedWriter};

 /// Gathers all Prometheus metrics and records the I/O stats just before that.
@@ -34,33 +35,47 @@ lazy_static! {
 }

 // Records I/O stats in a "cross-platform" way.
-// Compiles both on macOS and Linux, but current macOS implementation always returns 0 as values for I/O stats.
-// An alternative is to read procfs (`/proc/[pid]/io`) which does not work under macOS at all, hence abandoned.
+// Compiles both on macOs and Linux, but current macOs implementation always returns 0 as values for I/O stats.
+// An alternative is to read procfs (`/proc/[pid]/io`) which does not work under macOs at all, hence abandoned.
 //
 // Uses https://www.freebsd.org/cgi/man.cgi?query=getrusage to retrieve the number of block operations
 // performed by the process.
-// We know the size of the block, so we can determine the I/O bytes out of it.
+// We know the the size of the block, so we can determine the I/O bytes out of it.
 // The value might be not 100% exact, but should be fine for Prometheus metrics in this case.
-#[allow(clippy::unnecessary_cast)]
 fn update_io_metrics() {
-    let rusage_stats = get_rusage_stats();
+    let mut usage = rusage {
+        ru_utime: timeval {
+            tv_sec: 0 as time_t,
+            tv_usec: 0 as suseconds_t,
+        },
+        ru_stime: timeval {
+            tv_sec: 0 as time_t,
+            tv_usec: 0 as suseconds_t,
+        },
+        ru_maxrss: 0 as c_long,
+        ru_ixrss: 0 as c_long,
+        ru_idrss: 0 as c_long,
+        ru_isrss: 0 as c_long,
+        ru_minflt: 0 as c_long,
+        ru_majflt: 0 as c_long,
+        ru_nswap: 0 as c_long,
+        ru_inblock: 0 as c_long,
+        ru_oublock: 0 as c_long,
+        ru_msgsnd: 0 as c_long,
+        ru_msgrcv: 0 as c_long,
+        ru_nsignals: 0 as c_long,
+        ru_nvcsw: 0 as c_long,
+        ru_nivcsw: 0 as c_long,
+    };
+    unsafe {
+        getrusage(RUSAGE_SELF, (&mut usage) as *mut rusage);
+    }

    const BYTES_IN_BLOCK: i64 = 512;
    DISK_IO_BYTES
        .with_label_values(&["read"])
-        .set(rusage_stats.ru_inblock * BYTES_IN_BLOCK);
+        .set(usage.ru_inblock * BYTES_IN_BLOCK);
    DISK_IO_BYTES
        .with_label_values(&["write"])
-        .set(rusage_stats.ru_oublock * BYTES_IN_BLOCK);
-}
-
-fn get_rusage_stats() -> libc::rusage {
-    let mut rusage = std::mem::MaybeUninit::uninit();
-
-    // SAFETY: kernel will initialize the struct for us
-    unsafe {
-        let ret = libc::getrusage(libc::RUSAGE_SELF, rusage.as_mut_ptr());
-        assert!(ret == 0, "getrusage failed: bad args");
-        rusage.assume_init()
-    }
+        .set(usage.ru_oublock * BYTES_IN_BLOCK);
 }
--- a/zenith_metrics/src/wrappers.rs
+++ b/zenith_metrics/src/wrappers.rs
@@ -186,7 +186,7 @@ mod tests {
        assert_eq!(total, stream.len());
    }

-    // This mimics the constraints of std::thread::spawn
+    // This mimicks the constraints of std::thread::spawn
    fn assert_send_sync(_x: impl Sync + Send + 'static) {}

    #[test]
--- a/zenith_utils/Cargo.toml
+++ b/zenith_utils/Cargo.toml
@@ -17,13 +17,7 @@ routerify = "2"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1"
 thiserror = "1.0"
-tokio = "1.11"
-
-slog-async = "2.6.0"
-slog-stdlog = "4.1.0"
-slog-scope = "4.4.0"
-slog-term = "2.8.0"
-slog = "2.7.0"
+tokio = { version = "1.5.0", features = ["full"] }

 zenith_metrics = { path = "../zenith_metrics" }
 workspace_hack = { path = "../workspace_hack" }
--- a/zenith_utils/src/accum.rs
+++ b/zenith_utils/src/accum.rs
@@ -1,33 +0,0 @@
-/// A helper to "accumulate" a value similar to `Iterator::reduce`, but lets you
-/// feed the accumulated values by calling the 'accum' function, instead of having an
-/// iterator.
-///
-/// For example, to calculate the smallest value among some integers:
-///
-/// ```
-/// use zenith_utils::accum::Accum;
-///
-/// let values = [1, 2, 3];
-///
-/// let mut min_value: Accum<u32> = Accum(None);
-/// for new_value in &values {
-///     min_value.accum(std::cmp::min, *new_value);
-/// }
-///
-/// assert_eq!(min_value.0.unwrap(), 1);
-/// ```
-pub struct Accum<T>(pub Option<T>);
-impl<T: Copy> Accum<T> {
-    pub fn accum<F>(&mut self, func: F, new_value: T)
-    where
-        F: FnOnce(T, T) -> T,
-    {
-        // If there is no previous value, just store the new value.
-        // Otherwise call the function to decide which one to keep.
-        self.0 = Some(if let Some(accum) = self.0 {
-            func(accum, new_value)
-        } else {
-            new_value
-        });
-    }
-}
--- a/zenith_utils/src/auth.rs
+++ b/zenith_utils/src/auth.rs
@@ -1,6 +1,6 @@
 // For details about authentication see docs/authentication.md
 // TODO there are two issues for our use case in jsonwebtoken library which will be resolved in next release
-// The first one is that there is no way to disable expiration claim, but it can be excluded from validation, so use this as a workaround for now.
+// The fisrt one is that there is no way to disable expiration claim, but it can be excluded from validation, so use this as a workaround for now.
 // Relevant issue: https://github.com/Keats/jsonwebtoken/issues/190
 // The second one is that we wanted to use ed25519 keys, but they are also not supported until next version. So we go with RSA keys for now.
 // Relevant issue: https://github.com/Keats/jsonwebtoken/issues/162
@@ -8,8 +8,7 @@
 use hex::{self, FromHex};
 use serde::de::Error;
 use serde::{self, Deserializer, Serializer};
-use std::fs;
-use std::path::Path;
+use std::{fs, path::PathBuf};

 use anyhow::{bail, Result};
 use jsonwebtoken::{
@@ -44,8 +43,8 @@ where
 {
    let opt: Option<String> = Option::deserialize(deserializer)?;
    match opt {
-        Some(tid) => Ok(Some(ZTenantId::from_hex(tid).map_err(Error::custom)?)),
-        None => Ok(None),
+        Some(tid) => return Ok(Some(ZTenantId::from_hex(tid).map_err(Error::custom)?)),
+        None => return Ok(None),
    }
 }

@@ -92,7 +91,7 @@ pub struct JwtAuth {
 }

 impl JwtAuth {
-    pub fn new(decoding_key: DecodingKey<'_>) -> Self {
+    pub fn new<'a>(decoding_key: DecodingKey<'a>) -> Self {
        Self {
            decoding_key: decoding_key.into_static(),
            validation: Validation {
@@ -103,7 +102,7 @@ impl JwtAuth {
        }
    }

-    pub fn from_key_path(key_path: &Path) -> Result<Self> {
+    pub fn from_key_path(key_path: &PathBuf) -> Result<Self> {
        let public_key = fs::read_to_string(key_path)?;
        Ok(Self::new(DecodingKey::from_rsa_pem(public_key.as_bytes())?))
    }
@@ -114,8 +113,8 @@ impl JwtAuth {
 }

 // this function is used only for testing purposes in CLI e g generate tokens during init
-pub fn encode_from_key_path(claims: &Claims, key_path: &Path) -> Result<String> {
+pub fn encode_from_key_path(claims: &Claims, key_path: &PathBuf) -> Result<String> {
    let key_data = fs::read_to_string(key_path)?;
-    let key = EncodingKey::from_rsa_pem(key_data.as_bytes())?;
+    let key = EncodingKey::from_rsa_pem(&key_data.as_bytes())?;
    Ok(encode(&Header::new(JWT_ALGORITHM), claims, &key)?)
 }
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
anastasia	5e91d15f06	REVERT ME. Add unlink test and a bunch of debug printlns	2021-09-02 17:29:29 +03:00
anastasia	8c46178256	Attempt to fix list_rels & list_nonrels for dropped segments	2021-09-02 16:46:11 +03:00
anastasia	2a4d405f96	Rename put_unlink() to drop_relish() in Timeline trait. Rename put_unlink() to drop_segment() in Layer trait.	2021-09-02 16:37:05 +03:00
anastasia	66174c0342	Improve comments for Layer trait.	2021-09-02 16:33:47 +03:00
anastasia	cee366ac17	Don't use term 'snapshot' to describe layers	2021-09-02 16:33:30 +03:00