Move saving of stdin descriptor

.github/actionlint.yml

@@ -5,6 +5,4 @@ self-hosted-runner:
     - small
     - us-east-2
 config-variables:
-  - REMOTE_STORAGE_AZURE_CONTAINER
-  - REMOTE_STORAGE_AZURE_REGION
   - SLACK_UPCOMING_RELEASE_CHANNEL_ID

.github/actions/allure-report-generate/action.yml

@@ -203,10 +203,6 @@ runs:
         COMMIT_SHA: ${{ github.event.pull_request.head.sha || github.sha }}
         BASE_S3_URL: ${{ steps.generate-report.outputs.base-s3-url }}
       run: |
-        if [ ! -d "${WORKDIR}/report/data/test-cases" ]; then
-          exit 0
-        fi
-
         export DATABASE_URL=${REGRESS_TEST_RESULT_CONNSTR_NEW}
 
         ./scripts/pysync

.github/workflows/build_and_test.yml

@@ -320,9 +320,6 @@ jobs:
       - name: Build neon extensions
         run: mold -run make neon-pg-ext -j$(nproc)
 
-      - name: Build walproposer-lib
-        run: mold -run make walproposer-lib -j$(nproc)
-
       - name: Run cargo build
         run: |
           ${cov_prefix} mold -run cargo build $CARGO_FLAGS $CARGO_FEATURES --bins --tests
@@ -338,16 +335,6 @@ jobs:
           # Avoid `$CARGO_FEATURES` since there's no `testing` feature in the e2e tests now
           ${cov_prefix} cargo test $CARGO_FLAGS --package remote_storage --test test_real_s3
 
-          # Run separate tests for real Azure Blob Storage
-          # XXX: replace region with `eu-central-1`-like region
-          export ENABLE_REAL_AZURE_REMOTE_STORAGE=y
-          export AZURE_STORAGE_ACCOUNT="${{ secrets.AZURE_STORAGE_ACCOUNT_DEV }}"
-          export AZURE_STORAGE_ACCESS_KEY="${{ secrets.AZURE_STORAGE_ACCESS_KEY_DEV }}"
-          export REMOTE_STORAGE_AZURE_CONTAINER="${{ vars.REMOTE_STORAGE_AZURE_CONTAINER }}"
-          export REMOTE_STORAGE_AZURE_REGION="${{ vars.REMOTE_STORAGE_AZURE_REGION }}"
-          # Avoid `$CARGO_FEATURES` since there's no `testing` feature in the e2e tests now
-          ${cov_prefix} cargo test $CARGO_FLAGS --package remote_storage --test test_real_azure
-
       - name: Install rust binaries
         run: |
           # Install target binaries
@@ -433,7 +420,7 @@ jobs:
           rerun_flaky: true
           pg_version: ${{ matrix.pg_version }}
         env:
-          TEST_RESULT_CONNSTR: ${{ secrets.REGRESS_TEST_RESULT_CONNSTR_NEW }}
+          TEST_RESULT_CONNSTR: ${{ secrets.REGRESS_TEST_RESULT_CONNSTR }}
           CHECK_ONDISK_DATA_COMPATIBILITY: nonempty
 
       - name: Merge and upload coverage data
@@ -468,7 +455,7 @@ jobs:
         env:
           VIP_VAP_ACCESS_TOKEN: "${{ secrets.VIP_VAP_ACCESS_TOKEN }}"
           PERF_TEST_RESULT_CONNSTR: "${{ secrets.PERF_TEST_RESULT_CONNSTR }}"
-          TEST_RESULT_CONNSTR: "${{ secrets.REGRESS_TEST_RESULT_CONNSTR_NEW }}"
+          TEST_RESULT_CONNSTR: "${{ secrets.REGRESS_TEST_RESULT_CONNSTR }}"
       # XXX: no coverage data handling here, since benchmarks are run on release builds,
       # while coverage is currently collected for the debug ones
 
@@ -847,7 +834,7 @@ jobs:
       run:
         shell: sh -eu {0}
     env:
-      VM_BUILDER_VERSION: v0.18.5
+      VM_BUILDER_VERSION: v0.17.12
 
     steps:
       - name: Checkout

.github/workflows/neon_extra_builds.yml

@@ -32,7 +32,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
         with:
           submodules: true
           fetch-depth: 1
@@ -90,21 +90,18 @@ jobs:
 
       - name: Build postgres v14
         if: steps.cache_pg_14.outputs.cache-hit != 'true'
-        run: make postgres-v14 -j$(sysctl -n hw.ncpu)
+        run: make postgres-v14 -j$(nproc)
 
       - name: Build postgres v15
         if: steps.cache_pg_15.outputs.cache-hit != 'true'
-        run: make postgres-v15 -j$(sysctl -n hw.ncpu)
+        run: make postgres-v15 -j$(nproc)
 
       - name: Build postgres v16
         if: steps.cache_pg_16.outputs.cache-hit != 'true'
-        run: make postgres-v16 -j$(sysctl -n hw.ncpu)
+        run: make postgres-v16 -j$(nproc)
 
       - name: Build neon extensions
-        run: make neon-pg-ext -j$(sysctl -n hw.ncpu)
-
-      - name: Build walproposer-lib
-        run: make walproposer-lib -j$(sysctl -n hw.ncpu)
+        run: make neon-pg-ext -j$(nproc)
 
       - name: Run cargo build
         run: cargo build --all --release
@@ -129,7 +126,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
         with:
           submodules: true
           fetch-depth: 1
@@ -138,9 +135,6 @@ jobs:
       - name: Get postgres headers
         run: make postgres-headers -j$(nproc)
 
-      - name: Build walproposer-lib
-        run: make walproposer-lib -j$(nproc)
-
       - name: Produce the build stats
         run: cargo build --all --release --timings
 

.github/workflows/release.yml

@@ -2,7 +2,7 @@ name: Create Release Branch
 
 on:
   schedule:
-    - cron: '0 7 * * 5'
+    - cron: '0 7 * * 2'
   workflow_dispatch:
 
 jobs:

Cargo.toml

@@ -26,7 +26,6 @@ members = [
     "libs/tracing-utils",
     "libs/postgres_ffi/wal_craft",
     "libs/vm_monitor",
-    "libs/walproposer",
 ]
 
 [workspace.package]
@@ -37,10 +36,6 @@ license = "Apache-2.0"
 [workspace.dependencies]
 anyhow = { version = "1.0", features = ["backtrace"] }
 async-compression = { version = "0.4.0", features = ["tokio", "gzip"] }
-azure_core = "0.16"
-azure_identity = "0.16"
-azure_storage = "0.16"
-azure_storage_blobs = "0.16"
 flate2 = "1.0.26"
 async-stream = "0.3"
 async-trait = "0.1"
@@ -81,7 +76,6 @@ hex = "0.4"
 hex-literal = "0.4"
 hmac = "0.12.1"
 hostname = "0.3.1"
-http-types = "2"
 humantime = "2.1"
 humantime-serde = "1.1.1"
 hyper = "0.14"
@@ -161,11 +155,11 @@ env_logger = "0.10"
 log = "0.4"
 
 ## Libraries from neondatabase/ git forks, ideally with changes to be upstreamed
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
-postgres-native-tls = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
-postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
-postgres-types = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
+postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
+postgres-native-tls = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
+postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
+postgres-types = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
+tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
 
 ## Other git libraries
 heapless = { default-features=false, features=[], git = "https://github.com/japaric/heapless.git", rev = "644653bf3b831c6bb4963be2de24804acf5e5001" } # upstream release pending
@@ -186,7 +180,6 @@ tenant_size_model = { version = "0.1", path = "./libs/tenant_size_model/" }
 tracing-utils = { version = "0.1", path = "./libs/tracing-utils/" }
 utils = { version = "0.1", path = "./libs/utils/" }
 vm_monitor = { version = "0.1", path = "./libs/vm_monitor/" }
-walproposer = { version = "0.1", path = "./libs/walproposer/" }
 
 ## Common library dependency
 workspace_hack = { version = "0.1", path = "./workspace_hack/" }
@@ -202,7 +195,7 @@ tonic-build = "0.9"
 
 # This is only needed for proxy's tests.
 # TODO: we should probably fork `tokio-postgres-rustls` instead.
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="7434d9388965a17a6d113e5dfc0e65666a03b4c2" }
+tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="9011f7110db12b5e15afaf98f8ac834501d50ddc" }
 
 ################# Binary contents sections
 

Makefile

@@ -62,7 +62,7 @@ all: neon postgres neon-pg-ext
 #
 # The 'postgres_ffi' depends on the Postgres headers.
 .PHONY: neon
-neon: postgres-headers walproposer-lib
+neon: postgres-headers
 	+@echo "Compiling Neon"
 	$(CARGO_CMD_PREFIX) cargo build $(CARGO_BUILD_FLAGS)
 
@@ -168,42 +168,6 @@ neon-pg-ext-clean-%:
 	-C $(POSTGRES_INSTALL_DIR)/build/neon-utils-$* \
 	-f $(ROOT_PROJECT_DIR)/pgxn/neon_utils/Makefile clean
 
-# Build walproposer as a static library. walproposer source code is located
-# in the pgxn/neon directory.
-# 
-# We also need to include libpgport.a and libpgcommon.a, because walproposer
-# uses some functions from those libraries.
-# 
-# Some object files are removed from libpgport.a and libpgcommon.a because
-# they depend on openssl and other libraries that are not included in our
-# Rust build.
-.PHONY: walproposer-lib
-walproposer-lib: neon-pg-ext-v16
-	+@echo "Compiling walproposer-lib"
-	mkdir -p $(POSTGRES_INSTALL_DIR)/build/walproposer-lib
-	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/v16/bin/pg_config CFLAGS='$(PG_CFLAGS) $(COPT)' \
-		-C $(POSTGRES_INSTALL_DIR)/build/walproposer-lib \
-		-f $(ROOT_PROJECT_DIR)/pgxn/neon/Makefile walproposer-lib
-	cp $(POSTGRES_INSTALL_DIR)/v16/lib/libpgport.a $(POSTGRES_INSTALL_DIR)/build/walproposer-lib
-	cp $(POSTGRES_INSTALL_DIR)/v16/lib/libpgcommon.a $(POSTGRES_INSTALL_DIR)/build/walproposer-lib
-ifeq ($(UNAME_S),Linux)
-	$(AR) d $(POSTGRES_INSTALL_DIR)/build/walproposer-lib/libpgport.a \
-		pg_strong_random.o
-	$(AR) d $(POSTGRES_INSTALL_DIR)/build/walproposer-lib/libpgcommon.a \
-		pg_crc32c.o \
-		hmac_openssl.o \
-		cryptohash_openssl.o \
-		scram-common.o \
-		md5_common.o \
-		checksum_helper.o
-endif
-
-.PHONY: walproposer-lib-clean
-walproposer-lib-clean:
-	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/v16/bin/pg_config \
-		-C $(POSTGRES_INSTALL_DIR)/build/walproposer-lib \
-		-f $(ROOT_PROJECT_DIR)/pgxn/neon/Makefile clean
-
 .PHONY: neon-pg-ext
 neon-pg-ext: \
 	neon-pg-ext-v14 \

NOTICE

@@ -1,5 +1,5 @@
 Neon
 Copyright 2022 Neon Inc.
 
-The PostgreSQL submodules in vendor/ are licensed under the PostgreSQL license.
-See vendor/postgres-vX/COPYRIGHT for details.
+The PostgreSQL submodules in vendor/postgres-v14 and vendor/postgres-v15 are licensed under the
+PostgreSQL license. See vendor/postgres-v14/COPYRIGHT and vendor/postgres-v15/COPYRIGHT.

compute_tools/src/bin/compute_ctl.rs

@@ -156,7 +156,6 @@ fn main() -> Result<()> {
                 let path = Path::new(sp);
                 let file = File::open(path)?;
                 spec = Some(serde_json::from_reader(file)?);
-                live_config_allowed = true;
             } else if let Some(id) = compute_id {
                 if let Some(cp_base) = control_plane_uri {
                     live_config_allowed = true;
@@ -278,26 +277,32 @@ fn main() -> Result<()> {
         if #[cfg(target_os = "linux")] {
             use std::env;
             use tokio_util::sync::CancellationToken;
-            let vm_monitor_addr = matches
-                .get_one::<String>("vm-monitor-addr")
-                .expect("--vm-monitor-addr should always be set because it has a default arg");
+            use tracing::warn;
+            let vm_monitor_addr = matches.get_one::<String>("vm-monitor-addr");
             let file_cache_connstr = matches.get_one::<String>("filecache-connstr");
             let cgroup = matches.get_one::<String>("cgroup");
+            let file_cache_on_disk = matches.get_flag("file-cache-on-disk");
 
             // Only make a runtime if we need to.
             // Note: it seems like you can make a runtime in an inner scope and
             // if you start a task in it it won't be dropped. However, make it
             // in the outermost scope just to be safe.
-            let rt = if env::var_os("AUTOSCALING").is_some() {
-                Some(
+            let rt = match (env::var_os("AUTOSCALING"), vm_monitor_addr) {
+                (None, None) => None,
+                (None, Some(_)) => {
+                    warn!("--vm-monitor-addr option set but AUTOSCALING env var not present");
+                    None
+                }
+                (Some(_), None) => {
+                    panic!("AUTOSCALING env var present but --vm-monitor-addr option not set")
+                }
+                (Some(_), Some(_)) => Some(
                     tokio::runtime::Builder::new_multi_thread()
                         .worker_threads(4)
                         .enable_all()
                         .build()
-                        .expect("failed to create tokio runtime for monitor")
-                )
-            } else {
-                None
+                        .expect("failed to create tokio runtime for monitor"),
+                ),
             };
 
             // This token is used internally by the monitor to clean up all threads
@@ -308,7 +313,8 @@ fn main() -> Result<()> {
                     Box::leak(Box::new(vm_monitor::Args {
                         cgroup: cgroup.cloned(),
                         pgconnstr: file_cache_connstr.cloned(),
-                        addr: vm_monitor_addr.clone(),
+                        addr: vm_monitor_addr.cloned().unwrap(),
+                        file_cache_on_disk,
                     })),
                     token.clone(),
                 ))
@@ -480,8 +486,6 @@ fn cli() -> clap::Command {
                 .value_name("FILECACHE_CONNSTR"),
         )
         .arg(
-            // DEPRECATED, NO LONGER DOES ANYTHING.
-            // See https://github.com/neondatabase/cloud/issues/7516
             Arg::new("file-cache-on-disk")
                 .long("file-cache-on-disk")
                 .action(clap::ArgAction::SetTrue),

compute_tools/src/compute.rs

@@ -252,7 +252,7 @@ fn create_neon_superuser(spec: &ComputeSpec, client: &mut Client) -> Result<()>
                     IF NOT EXISTS (
                         SELECT FROM pg_catalog.pg_roles WHERE rolname = 'neon_superuser')
                     THEN
-                        CREATE ROLE neon_superuser CREATEDB CREATEROLE NOLOGIN REPLICATION IN ROLE pg_read_all_data, pg_write_all_data;
+                        CREATE ROLE neon_superuser CREATEDB CREATEROLE NOLOGIN IN ROLE pg_read_all_data, pg_write_all_data;
                         IF array_length(roles, 1) IS NOT NULL THEN
                             EXECUTE format('GRANT neon_superuser TO %s',
                                            array_to_string(ARRAY(SELECT quote_ident(x) FROM unnest(roles) as x), ', '));
@@ -692,11 +692,10 @@ impl ComputeNode {
         // Proceed with post-startup configuration. Note, that order of operations is important.
         let spec = &compute_state.pspec.as_ref().expect("spec must be set").spec;
         create_neon_superuser(spec, &mut client)?;
-        cleanup_instance(&mut client)?;
         handle_roles(spec, &mut client)?;
         handle_databases(spec, &mut client)?;
         handle_role_deletions(spec, self.connstr.as_str(), &mut client)?;
-        handle_grants(spec, &mut client, self.connstr.as_str())?;
+        handle_grants(spec, self.connstr.as_str())?;
         handle_extensions(spec, &mut client)?;
         create_availability_check_data(&mut client)?;
 
@@ -732,11 +731,10 @@ impl ComputeNode {
         // Disable DDL forwarding because control plane already knows about these roles/databases.
         if spec.mode == ComputeMode::Primary {
             client.simple_query("SET neon.forward_ddl = false")?;
-            cleanup_instance(&mut client)?;
             handle_roles(&spec, &mut client)?;
             handle_databases(&spec, &mut client)?;
             handle_role_deletions(&spec, self.connstr.as_str(), &mut client)?;
-            handle_grants(&spec, &mut client, self.connstr.as_str())?;
+            handle_grants(&spec, self.connstr.as_str())?;
             handle_extensions(&spec, &mut client)?;
         }
 

compute_tools/src/pg_helpers.rs

@@ -1,4 +1,3 @@
-use std::collections::HashMap;
 use std::fmt::Write;
 use std::fs;
 use std::fs::File;
@@ -193,16 +192,11 @@ impl Escaping for PgIdent {
 /// Build a list of existing Postgres roles
 pub fn get_existing_roles(xact: &mut Transaction<'_>) -> Result<Vec<Role>> {
     let postgres_roles = xact
-        .query(
-            "SELECT rolname, rolpassword, rolreplication, rolbypassrls FROM pg_catalog.pg_authid",
-            &[],
-        )?
+        .query("SELECT rolname, rolpassword FROM pg_catalog.pg_authid", &[])?
         .iter()
         .map(|row| Role {
             name: row.get("rolname"),
             encrypted_password: row.get("rolpassword"),
-            replication: Some(row.get("rolreplication")),
-            bypassrls: Some(row.get("rolbypassrls")),
             options: None,
         })
         .collect();
@@ -211,37 +205,22 @@ pub fn get_existing_roles(xact: &mut Transaction<'_>) -> Result<Vec<Role>> {
 }
 
 /// Build a list of existing Postgres databases
-pub fn get_existing_dbs(client: &mut Client) -> Result<HashMap<String, Database>> {
-    // `pg_database.datconnlimit = -2` means that the database is in the
-    // invalid state. See:
-    //   https://github.com/postgres/postgres/commit/a4b4cc1d60f7e8ccfcc8ff8cb80c28ee411ad9a9
-    let postgres_dbs: Vec<Database> = client
+pub fn get_existing_dbs(client: &mut Client) -> Result<Vec<Database>> {
+    let postgres_dbs = client
         .query(
-            "SELECT
-                datname AS name,
-                datdba::regrole::text AS owner,
-                NOT datallowconn AS restrict_conn,
-                datconnlimit = - 2 AS invalid
-            FROM
-                pg_catalog.pg_database;",
+            "SELECT datname, datdba::regrole::text as owner
+               FROM pg_catalog.pg_database;",
             &[],
         )?
         .iter()
         .map(|row| Database {
-            name: row.get("name"),
+            name: row.get("datname"),
             owner: row.get("owner"),
-            restrict_conn: row.get("restrict_conn"),
-            invalid: row.get("invalid"),
             options: None,
         })
         .collect();
 
-    let dbs_map = postgres_dbs
-        .iter()
-        .map(|db| (db.name.clone(), db.clone()))
-        .collect::<HashMap<_, _>>();
-
-    Ok(dbs_map)
+    Ok(postgres_dbs)
 }
 
 /// Wait for Postgres to become ready to accept connections. It's ready to

compute_tools/src/spec.rs

@@ -13,7 +13,7 @@ use crate::params::PG_HBA_ALL_MD5;
 use crate::pg_helpers::*;
 
 use compute_api::responses::{ControlPlaneComputeStatus, ControlPlaneSpecResponse};
-use compute_api::spec::{ComputeSpec, PgIdent, Role};
+use compute_api::spec::{ComputeSpec, Database, PgIdent, Role};
 
 // Do control plane request and return response if any. In case of error it
 // returns a bool flag indicating whether it makes sense to retry the request
@@ -24,7 +24,7 @@ fn do_control_plane_request(
 ) -> Result<ControlPlaneSpecResponse, (bool, String)> {
     let resp = reqwest::blocking::Client::new()
         .get(uri)
-        .header("Authorization", format!("Bearer {}", jwt))
+        .header("Authorization", jwt)
         .send()
         .map_err(|e| {
             (
@@ -161,38 +161,6 @@ pub fn add_standby_signal(pgdata_path: &Path) -> Result<()> {
     Ok(())
 }
 
-/// Compute could be unexpectedly shut down, for example, during the
-/// database dropping. This leaves the database in the invalid state,
-/// which prevents new db creation with the same name. This function
-/// will clean it up before proceeding with catalog updates. All
-/// possible future cleanup operations may go here too.
-#[instrument(skip_all)]
-pub fn cleanup_instance(client: &mut Client) -> Result<()> {
-    let existing_dbs = get_existing_dbs(client)?;
-
-    for (_, db) in existing_dbs {
-        if db.invalid {
-            // After recent commit in Postgres, interrupted DROP DATABASE
-            // leaves the database in the invalid state. According to the
-            // commit message, the only option for user is to drop it again.
-            // See:
-            //   https://github.com/postgres/postgres/commit/a4b4cc1d60f7e8ccfcc8ff8cb80c28ee411ad9a9
-            //
-            // Postgres Neon extension is done the way, that db is de-registered
-            // in the control plane metadata only after it is dropped. So there is
-            // a chance that it still thinks that db should exist. This means
-            // that it will be re-created by `handle_databases()`. Yet, it's fine
-            // as user can just repeat drop (in vanilla Postgres they would need
-            // to do the same, btw).
-            let query = format!("DROP DATABASE IF EXISTS {}", db.name.pg_quote());
-            info!("dropping invalid database {}", db.name);
-            client.execute(query.as_str(), &[])?;
-        }
-    }
-
-    Ok(())
-}
-
 /// Given a cluster spec json and open transaction it handles roles creation,
 /// deletion and update.
 #[instrument(skip_all)]
@@ -265,8 +233,6 @@ pub fn handle_roles(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
         let action = if let Some(r) = pg_role {
             if (r.encrypted_password.is_none() && role.encrypted_password.is_some())
                 || (r.encrypted_password.is_some() && role.encrypted_password.is_none())
-                || !r.bypassrls.unwrap_or(false)
-                || !r.replication.unwrap_or(false)
             {
                 RoleAction::Update
             } else if let Some(pg_pwd) = &r.encrypted_password {
@@ -298,14 +264,13 @@ pub fn handle_roles(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
         match action {
             RoleAction::None => {}
             RoleAction::Update => {
-                let mut query: String =
-                    format!("ALTER ROLE {} BYPASSRLS REPLICATION", name.pg_quote());
+                let mut query: String = format!("ALTER ROLE {} ", name.pg_quote());
                 query.push_str(&role.to_pg_options());
                 xact.execute(query.as_str(), &[])?;
             }
             RoleAction::Create => {
                 let mut query: String = format!(
-                    "CREATE ROLE {} CREATEROLE CREATEDB BYPASSRLS REPLICATION IN ROLE neon_superuser",
+                    "CREATE ROLE {} CREATEROLE CREATEDB BYPASSRLS IN ROLE neon_superuser",
                     name.pg_quote()
                 );
                 info!("role create query: '{}'", &query);
@@ -414,13 +379,13 @@ fn reassign_owned_objects(spec: &ComputeSpec, connstr: &str, role_name: &PgIdent
 /// which together provide us idempotency.
 #[instrument(skip_all)]
 pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
-    let existing_dbs = get_existing_dbs(client)?;
+    let existing_dbs: Vec<Database> = get_existing_dbs(client)?;
 
     // Print a list of existing Postgres databases (only in debug mode)
     if span_enabled!(Level::INFO) {
         info!("postgres databases:");
-        for (dbname, db) in &existing_dbs {
-            info!("    {}:{}", dbname, db.owner);
+        for r in &existing_dbs {
+            info!("    {}:{}", r.name, r.owner);
         }
     }
 
@@ -474,7 +439,8 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
                 "rename_db" => {
                     let new_name = op.new_name.as_ref().unwrap();
 
-                    if existing_dbs.get(&op.name).is_some() {
+                    // XXX: with a limited number of roles it is fine, but consider making it a HashMap
+                    if existing_dbs.iter().any(|r| r.name == op.name) {
                         let query: String = format!(
                             "ALTER DATABASE {} RENAME TO {}",
                             op.name.pg_quote(),
@@ -491,12 +457,14 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
     }
 
     // Refresh Postgres databases info to handle possible renames
-    let existing_dbs = get_existing_dbs(client)?;
+    let existing_dbs: Vec<Database> = get_existing_dbs(client)?;
 
     info!("cluster spec databases:");
     for db in &spec.cluster.databases {
         let name = &db.name;
-        let pg_db = existing_dbs.get(name);
+
+        // XXX: with a limited number of databases it is fine, but consider making it a HashMap
+        let pg_db = existing_dbs.iter().find(|r| r.name == *name);
 
         enum DatabaseAction {
             None,
@@ -562,32 +530,13 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
 /// Grant CREATE ON DATABASE to the database owner and do some other alters and grants
 /// to allow users creating trusted extensions and re-creating `public` schema, for example.
 #[instrument(skip_all)]
-pub fn handle_grants(spec: &ComputeSpec, client: &mut Client, connstr: &str) -> Result<()> {
-    info!("modifying database permissions");
-    let existing_dbs = get_existing_dbs(client)?;
+pub fn handle_grants(spec: &ComputeSpec, connstr: &str) -> Result<()> {
+    info!("cluster spec grants:");
 
     // Do some per-database access adjustments. We'd better do this at db creation time,
     // but CREATE DATABASE isn't transactional. So we cannot create db + do some grants
     // atomically.
     for db in &spec.cluster.databases {
-        match existing_dbs.get(&db.name) {
-            Some(pg_db) => {
-                if pg_db.restrict_conn || pg_db.invalid {
-                    info!(
-                        "skipping grants for db {} (invalid: {}, connections not allowed: {})",
-                        db.name, pg_db.invalid, pg_db.restrict_conn
-                    );
-                    continue;
-                }
-            }
-            None => {
-                bail!(
-                    "database {} doesn't exist in Postgres after handle_databases()",
-                    db.name
-                );
-            }
-        }
-
         let mut conf = Config::from_str(connstr)?;
         conf.dbname(&db.name);
 
@@ -626,11 +575,6 @@ pub fn handle_grants(spec: &ComputeSpec, client: &mut Client, connstr: &str) ->
 
         // Explicitly grant CREATE ON SCHEMA PUBLIC to the web_access user.
         // This is needed because since postgres 15 this privilege is removed by default.
-        // TODO: web_access isn't created for almost 1 year. It could be that we have
-        // active users of 1 year old projects, but hopefully not, so check it and
-        // remove this code if possible. The worst thing that could happen is that
-        // user won't be able to use public schema in NEW databases created in the
-        // very OLD project.
         let grant_query = "DO $$\n\
                 BEGIN\n\
                     IF EXISTS(\n\

compute_tools/tests/pg_helpers_tests.rs

@@ -28,7 +28,7 @@ mod pg_helpers_tests {
         assert_eq!(
             spec.cluster.settings.as_pg_settings(),
             r#"fsync = off
-wal_level = logical
+wal_level = replica
 hot_standby = on
 neon.safekeepers = '127.0.0.1:6502,127.0.0.1:6503,127.0.0.1:6501'
 wal_log_hints = on

control_plane/src/attachment_service.rs

@@ -19,7 +19,7 @@ const COMMAND: &str = "attachment_service";
 pub struct AttachHookRequest {
     #[serde_as(as = "DisplayFromStr")]
     pub tenant_id: TenantId,
-    pub node_id: Option<NodeId>,
+    pub pageserver_id: Option<NodeId>,
 }
 
 #[derive(Serialize, Deserialize)]
@@ -85,7 +85,7 @@ impl AttachmentService {
             .control_plane_api
             .clone()
             .unwrap()
-            .join("attach-hook")
+            .join("attach_hook")
             .unwrap();
         let client = reqwest::blocking::ClientBuilder::new()
             .build()
@@ -93,7 +93,7 @@ impl AttachmentService {
 
         let request = AttachHookRequest {
             tenant_id,
-            node_id: Some(pageserver_id),
+            pageserver_id: Some(pageserver_id),
         };
 
         let response = client.post(url).json(&request).send()?;

control_plane/src/background_process.rs

@@ -86,7 +86,7 @@ where
         .stdout(process_log_file)
         .stderr(same_file_for_stderr)
         .args(args);
-    let filled_cmd = fill_remote_storage_secrets_vars(fill_rust_env_vars(background_command));
+    let filled_cmd = fill_aws_secrets_vars(fill_rust_env_vars(background_command));
     filled_cmd.envs(envs);
 
     let pid_file_to_check = match initial_pid_file {
@@ -238,13 +238,11 @@ fn fill_rust_env_vars(cmd: &mut Command) -> &mut Command {
     filled_cmd
 }
 
-fn fill_remote_storage_secrets_vars(mut cmd: &mut Command) -> &mut Command {
+fn fill_aws_secrets_vars(mut cmd: &mut Command) -> &mut Command {
     for env_key in [
         "AWS_ACCESS_KEY_ID",
         "AWS_SECRET_ACCESS_KEY",
         "AWS_SESSION_TOKEN",
-        "AZURE_STORAGE_ACCOUNT",
-        "AZURE_STORAGE_ACCESS_KEY",
     ] {
         if let Ok(value) = std::env::var(env_key) {
             cmd = cmd.env(env_key, value);

control_plane/src/bin/attachment_service.rs

@@ -12,9 +12,7 @@ use hyper::{Body, Request, Response};
 use serde::{Deserialize, Serialize};
 use std::path::{Path, PathBuf};
 use std::{collections::HashMap, sync::Arc};
-use utils::http::endpoint::request_span;
 use utils::logging::{self, LogFormat};
-use utils::signals::{ShutdownSignals, Signal};
 
 use utils::{
     http::{
@@ -172,7 +170,7 @@ async fn handle_re_attach(mut req: Request<Body>) -> Result<Response<Body>, ApiE
             state.generation += 1;
             response.tenants.push(ReAttachResponseTenant {
                 id: *t,
-                gen: state.generation,
+                generation: state.generation,
             });
         }
     }
@@ -218,31 +216,14 @@ async fn handle_attach_hook(mut req: Request<Body>) -> Result<Response<Body>, Ap
         .tenants
         .entry(attach_req.tenant_id)
         .or_insert_with(|| TenantState {
-            pageserver: attach_req.node_id,
+            pageserver: attach_req.pageserver_id,
             generation: 0,
         });
 
-    if let Some(attaching_pageserver) = attach_req.node_id.as_ref() {
+    if attach_req.pageserver_id.is_some() {
         tenant_state.generation += 1;
-        tracing::info!(
-            tenant_id = %attach_req.tenant_id,
-            ps_id = %attaching_pageserver,
-            generation = %tenant_state.generation,
-            "issuing",
-        );
-    } else if let Some(ps_id) = tenant_state.pageserver {
-        tracing::info!(
-            tenant_id = %attach_req.tenant_id,
-            %ps_id,
-            generation = %tenant_state.generation,
-            "dropping",
-        );
-    } else {
-        tracing::info!(
-            tenant_id = %attach_req.tenant_id,
-            "no-op: tenant already has no pageserver");
     }
-    tenant_state.pageserver = attach_req.node_id;
+    tenant_state.pageserver = attach_req.pageserver_id;
     let generation = tenant_state.generation;
 
     locked.save().await.map_err(ApiError::InternalServerError)?;
@@ -250,7 +231,7 @@ async fn handle_attach_hook(mut req: Request<Body>) -> Result<Response<Body>, Ap
     json_response(
         StatusCode::OK,
         AttachHookResponse {
-            gen: attach_req.node_id.map(|_| generation),
+            gen: attach_req.pageserver_id.map(|_| generation),
         },
     )
 }
@@ -258,9 +239,9 @@ async fn handle_attach_hook(mut req: Request<Body>) -> Result<Response<Body>, Ap
 fn make_router(persistent_state: PersistentState) -> RouterBuilder<hyper::Body, ApiError> {
     endpoint::make_router()
         .data(Arc::new(State::new(persistent_state)))
-        .post("/re-attach", |r| request_span(r, handle_re_attach))
-        .post("/validate", |r| request_span(r, handle_validate))
-        .post("/attach-hook", |r| request_span(r, handle_attach_hook))
+        .post("/re-attach", handle_re_attach)
+        .post("/validate", handle_validate)
+        .post("/attach_hook", handle_attach_hook)
 }
 
 #[tokio::main]
@@ -287,16 +268,7 @@ async fn main() -> anyhow::Result<()> {
     let server = hyper::Server::from_tcp(http_listener)?.serve(service);
 
     tracing::info!("Serving on {0}", args.listen);
-
-    tokio::task::spawn(server);
-
-    ShutdownSignals::handle(|signal| match signal {
-        Signal::Interrupt | Signal::Terminate | Signal::Quit => {
-            tracing::info!("Got {}. Terminating", signal.name());
-            // We're just a test helper: no graceful shutdown.
-            std::process::exit(0);
-        }
-    })?;
+    server.await?;
 
     Ok(())
 }

control_plane/src/bin/neon_local.rs

@@ -798,24 +798,6 @@ fn handle_endpoint(ep_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<(
                 ep.start(&auth_token, safekeepers, remote_ext_config)?;
             }
         }
-        "reconfigure" => {
-            let endpoint_id = sub_args
-                .get_one::<String>("endpoint_id")
-                .ok_or_else(|| anyhow!("No endpoint ID provided to reconfigure"))?;
-            let endpoint = cplane
-                .endpoints
-                .get(endpoint_id.as_str())
-                .with_context(|| format!("postgres endpoint {endpoint_id} is not found"))?;
-            let pageserver_id =
-                if let Some(id_str) = sub_args.get_one::<String>("endpoint-pageserver-id") {
-                    Some(NodeId(
-                        id_str.parse().context("while parsing pageserver id")?,
-                    ))
-                } else {
-                    None
-                };
-            endpoint.reconfigure(pageserver_id)?;
-        }
         "stop" => {
             let endpoint_id = sub_args
                 .get_one::<String>("endpoint_id")
@@ -1387,12 +1369,6 @@ fn cli() -> Command {
                     .arg(safekeepers_arg)
                     .arg(remote_ext_config_args)
                 )
-                .subcommand(Command::new("reconfigure")
-                            .about("Reconfigure the endpoint")
-                            .arg(endpoint_pageserver_id_arg)
-                            .arg(endpoint_id_arg.clone())
-                            .arg(tenant_id_arg.clone())
-                )
                 .subcommand(
                     Command::new("stop")
                     .arg(endpoint_id_arg)

control_plane/src/endpoint.rs

@@ -253,7 +253,7 @@ impl Endpoint {
         conf.append("shared_buffers", "1MB");
         conf.append("fsync", "off");
         conf.append("max_connections", "100");
-        conf.append("wal_level", "logical");
+        conf.append("wal_level", "replica");
         // wal_sender_timeout is the maximum time to wait for WAL replication.
         // It also defines how often the walreciever will send a feedback message to the wal sender.
         conf.append("wal_sender_timeout", "5s");
@@ -414,32 +414,16 @@ impl Endpoint {
             );
         }
 
-        Ok(())
-    }
-
-    fn wait_for_compute_ctl_to_exit(&self) -> Result<()> {
+        // Also wait for the compute_ctl process to die. It might have some cleanup
+        // work to do after postgres stops, like syncing safekeepers, etc.
+        //
         // TODO use background_process::stop_process instead
         let pidfile_path = self.endpoint_path().join("compute_ctl.pid");
         let pid: u32 = std::fs::read_to_string(pidfile_path)?.parse()?;
         let pid = nix::unistd::Pid::from_raw(pid as i32);
         crate::background_process::wait_until_stopped("compute_ctl", pid)?;
-        Ok(())
-    }
 
-    fn read_postgresql_conf(&self) -> Result<String> {
-        // Slurp the endpoints/<endpoint id>/postgresql.conf file into
-        // memory. We will include it in the spec file that we pass to
-        // `compute_ctl`, and `compute_ctl` will write it to the postgresql.conf
-        // in the data directory.
-        let postgresql_conf_path = self.endpoint_path().join("postgresql.conf");
-        match std::fs::read(&postgresql_conf_path) {
-            Ok(content) => Ok(String::from_utf8(content)?),
-            Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok("".to_string()),
-            Err(e) => Err(anyhow::Error::new(e).context(format!(
-                "failed to read config file in {}",
-                postgresql_conf_path.to_str().unwrap()
-            ))),
-        }
+        Ok(())
     }
 
     pub fn start(
@@ -452,7 +436,21 @@ impl Endpoint {
             anyhow::bail!("The endpoint is already running");
         }
 
-        let postgresql_conf = self.read_postgresql_conf()?;
+        // Slurp the endpoints/<endpoint id>/postgresql.conf file into
+        // memory. We will include it in the spec file that we pass to
+        // `compute_ctl`, and `compute_ctl` will write it to the postgresql.conf
+        // in the data directory.
+        let postgresql_conf_path = self.endpoint_path().join("postgresql.conf");
+        let postgresql_conf = match std::fs::read(&postgresql_conf_path) {
+            Ok(content) => String::from_utf8(content)?,
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => "".to_string(),
+            Err(e) => {
+                return Err(anyhow::Error::new(e).context(format!(
+                    "failed to read config file in {}",
+                    postgresql_conf_path.to_str().unwrap()
+                )))
+            }
+        };
 
         // We always start the compute node from scratch, so if the Postgres
         // data dir exists from a previous launch, remove it first.
@@ -623,61 +621,6 @@ impl Endpoint {
         }
     }
 
-    pub fn reconfigure(&self, pageserver_id: Option<NodeId>) -> Result<()> {
-        let mut spec: ComputeSpec = {
-            let spec_path = self.endpoint_path().join("spec.json");
-            let file = std::fs::File::open(spec_path)?;
-            serde_json::from_reader(file)?
-        };
-
-        let postgresql_conf = self.read_postgresql_conf()?;
-        spec.cluster.postgresql_conf = Some(postgresql_conf);
-
-        if let Some(pageserver_id) = pageserver_id {
-            let endpoint_config_path = self.endpoint_path().join("endpoint.json");
-            let mut endpoint_conf: EndpointConf = {
-                let file = std::fs::File::open(&endpoint_config_path)?;
-                serde_json::from_reader(file)?
-            };
-            endpoint_conf.pageserver_id = pageserver_id;
-            std::fs::write(
-                endpoint_config_path,
-                serde_json::to_string_pretty(&endpoint_conf)?,
-            )?;
-
-            let pageserver =
-                PageServerNode::from_env(&self.env, self.env.get_pageserver_conf(pageserver_id)?);
-            let ps_http_conf = &pageserver.pg_connection_config;
-            let (host, port) = (ps_http_conf.host(), ps_http_conf.port());
-            spec.pageserver_connstring = Some(format!("postgresql://no_user@{host}:{port}"));
-        }
-
-        let client = reqwest::blocking::Client::new();
-        let response = client
-            .post(format!(
-                "http://{}:{}/configure",
-                self.http_address.ip(),
-                self.http_address.port()
-            ))
-            .body(format!(
-                "{{\"spec\":{}}}",
-                serde_json::to_string_pretty(&spec)?
-            ))
-            .send()?;
-
-        let status = response.status();
-        if !(status.is_client_error() || status.is_server_error()) {
-            Ok(())
-        } else {
-            let url = response.url().to_owned();
-            let msg = match response.text() {
-                Ok(err_body) => format!("Error: {}", err_body),
-                Err(_) => format!("Http error ({}) at {}.", status.as_u16(), url),
-            };
-            Err(anyhow::anyhow!(msg))
-        }
-    }
-
     pub fn stop(&self, destroy: bool) -> Result<()> {
         // If we are going to destroy data directory,
         // use immediate shutdown mode, otherwise,
@@ -686,25 +629,15 @@ impl Endpoint {
         // Postgres is always started from scratch, so stop
         // without destroy only used for testing and debugging.
         //
-        self.pg_ctl(
-            if destroy {
-                &["-m", "immediate", "stop"]
-            } else {
-                &["stop"]
-            },
-            &None,
-        )?;
-
-        // Also wait for the compute_ctl process to die. It might have some cleanup
-        // work to do after postgres stops, like syncing safekeepers, etc.
-        //
-        self.wait_for_compute_ctl_to_exit()?;
         if destroy {
+            self.pg_ctl(&["-m", "immediate", "stop"], &None)?;
             println!(
                 "Destroying postgres data directory '{}'",
                 self.pgdata().to_str().unwrap()
             );
             std::fs::remove_dir_all(self.endpoint_path())?;
+        } else {
+            self.pg_ctl(&["stop"], &None)?;
         }
         Ok(())
     }

docker-compose/compute_wrapper/var/db/postgres/specs/spec.json

@@ -25,7 +25,7 @@
             },
             {
                 "name": "wal_level",
-                "value": "logical",
+                "value": "replica",
                 "vartype": "enum"
             },
             {

docs/error-handling.md

@@ -188,60 +188,11 @@ that.
 
 ## Error message style
 
-### PostgreSQL extensions
-
 PostgreSQL has a style guide for writing error messages:
 
 https://www.postgresql.org/docs/current/error-style-guide.html
 
 Follow that guide when writing error messages in the PostgreSQL
-extensions.
-
-### Neon Rust code
-
-#### Anyhow Context
-
-When adding anyhow `context()`, use form `present-tense-verb+action`.
-
-Example:
-- Bad: `file.metadata().context("could not get file metadata")?;`
-- Good: `file.metadata().context("get file metadata")?;`
-
-#### Logging Errors
-
-When logging any error `e`, use `could not {e:#}` or `failed to {e:#}`.
-
-If `e` is an `anyhow` error and you want to log the backtrace that it contains,
-use `{e:?}` instead of `{e:#}`.
-
-#### Rationale
-
-The `{:#}` ("alternate Display") of an `anyhow` error chain is concatenation fo the contexts, using `: `.
-
-For example, the following Rust code will result in output
-```
-ERROR  failed to list users: load users from server: parse response: invalid json
-```
-
-This is more concise / less noisy than what happens if you do `.context("could not ...")?` at each level, i.e.:
-
-```
-ERROR  could not list users: could not load users from server: could not parse response: invalid json
-```
-
-
-```rust
-fn main() {
-  match list_users().context("list users") else {
-    Ok(_) => ...,
-    Err(e) => tracing::error!("failed to {e:#}"),
-  }
-}
-fn list_users() {
-  http_get_users().context("load users from server")?;
-}
-fn http_get_users() {
-  let response = client....?;
-  response.parse().context("parse response")?; // fails with serde error "invalid json"
-}
-```
+extension. We don't follow it strictly in the pageserver and
+safekeeper, but the advice in the PostgreSQL style guide is generally
+good, and you can't go wrong by following it.

docs/pageserver-services.md

@@ -96,16 +96,6 @@ prefix_in_bucket = '/test_prefix/'
 
 `AWS_SECRET_ACCESS_KEY` and `AWS_ACCESS_KEY_ID` env variables can be used to specify the S3 credentials if needed.
 
-or
-
-```toml
-[remote_storage]
-container_name = 'some-container-name'
-container_region = 'us-east'
-prefix_in_container = '/test-prefix/'
-```
-
-`AZURE_STORAGE_ACCOUNT` and `AZURE_STORAGE_ACCESS_KEY` env variables can be used to specify the azure credentials if needed.
 
 ## Repository background tasks
 

docs/updating-postgres.md

@@ -1,108 +0,0 @@
-# Updating Postgres
-
-## Minor Versions
-
-When upgrading to a new minor version of Postgres, please follow these steps:
-
-_Example: 15.4 is the new minor version to upgrade to from 15.3._
-
-1. Clone the Neon Postgres repository if you have not done so already.
-
-    ```shell
-    git clone git@github.com:neondatabase/postgres.git
-    ```
-
-1. Add the Postgres upstream remote.
-
-    ```shell
-    git remote add upstream https://git.postgresql.org/git/postgresql.git
-    ```
-
-1. Create a new branch based on the stable branch you are updating.
-
-    ```shell
-    git checkout -b my-branch REL_15_STABLE_neon
-    ```
-
-1. Tag the last commit on the stable branch you are updating.
-
-    ```shell
-    git tag REL_15_3_neon
-    ```
-
-1. Push the new tag to the Neon Postgres repository.
-
-    ```shell
-    git push origin REL_15_3_neon
-    ```
-
-1. Find the release tags you're looking for. They are of the form `REL_X_Y`.
-
-1. Rebase the branch you created on the tag and resolve any conflicts.
-
-    ```shell
-    git fetch upstream REL_15_4
-    git rebase REL_15_4
-    ```
-
-1. Run the Postgres test suite to make sure our commits have not affected
-Postgres in a negative way.
-
-    ```shell
-    make check
-    # OR
-    meson test -C builddir
-    ```
-
-1. Push your branch to the Neon Postgres repository.
-
-    ```shell
-    git push origin my-branch
-    ```
-
-1. Clone the Neon repository if you have not done so already.
-
-    ```shell
-    git clone git@github.com:neondatabase/neon.git
-    ```
-
-1. Create a new branch.
-
-1. Change the `revisions.json` file to point at the HEAD of your Postgres
-branch.
-
-1. Update the Git submodule.
-
-    ```shell
-    git submodule set-branch --branch my-branch vendor/postgres-v15
-    git submodule update --remote vendor/postgres-v15
-    ```
-
-1. Run the Neon test suite to make sure that Neon is still good to go on this
-minor Postgres release.
-
-    ```shell
-    ./scripts/poetry -k pg15
-    ```
-
-1. Commit your changes.
-
-1. Create a pull request, and wait for CI to go green.
-
-1. Force push the rebased Postgres branches into the Neon Postgres repository.
-
-    ```shell
-    git push --force origin my-branch:REL_15_STABLE_neon
-    ```
-
-    It may require disabling various branch protections.
-
-1. Update your Neon PR to point at the branches.
-
-    ```shell
-    git submodule set-branch --branch REL_15_STABLE_neon vendor/postgres-v15
-    git commit --amend --no-edit
-    git push --force origin
-    ```
-
-1. Merge the pull request after getting approval(s) and CI completion.

libs/compute_api/src/spec.rs

@@ -190,8 +190,6 @@ pub struct DeltaOp {
 pub struct Role {
     pub name: PgIdent,
     pub encrypted_password: Option<String>,
-    pub replication: Option<bool>,
-    pub bypassrls: Option<bool>,
     pub options: GenericOptions,
 }
 
@@ -202,12 +200,6 @@ pub struct Database {
     pub name: PgIdent,
     pub owner: PgIdent,
     pub options: GenericOptions,
-    // These are derived flags, not present in the spec file.
-    // They are never set by the control plane.
-    #[serde(skip_deserializing, default)]
-    pub restrict_conn: bool,
-    #[serde(skip_deserializing, default)]
-    pub invalid: bool,
 }
 
 /// Common type representing both SQL statement params with or without value,

libs/compute_api/tests/cluster_spec.json

@@ -76,7 +76,7 @@
             },
             {
                 "name": "wal_level",
-                "value": "logical",
+                "value": "replica",
                 "vartype": "enum"
             },
             {

libs/metrics/src/lib.rs

@@ -89,14 +89,14 @@ pub const DISK_WRITE_SECONDS_BUCKETS: &[f64] = &[
     0.000_050, 0.000_100, 0.000_500, 0.001, 0.003, 0.005, 0.01, 0.05, 0.1, 0.3, 0.5,
 ];
 
-pub fn set_build_info_metric(revision: &str, build_tag: &str) {
+pub fn set_build_info_metric(revision: &str) {
     let metric = register_int_gauge_vec!(
         "libmetrics_build_info",
         "Build/version information",
-        &["revision", "build_tag"]
+        &["revision"]
     )
     .expect("Failed to register build info metric");
-    metric.with_label_values(&[revision, build_tag]).set(1);
+    metric.with_label_values(&[revision]).set(1);
 }
 
 // Records I/O stats in a "cross-platform" way.

libs/metrics/src/wrappers.rs

@@ -1,6 +1,6 @@
 use std::io::{Read, Result, Write};
 
-/// A wrapper for an object implementing [Read]
+/// A wrapper for an object implementing [Read](std::io::Read)
 /// which allows a closure to observe the amount of bytes read.
 /// This is useful in conjunction with metrics (e.g. [IntCounter](crate::IntCounter)).
 ///
@@ -51,17 +51,17 @@ impl<'a, T> CountedReader<'a, T> {
         }
     }
 
-    /// Get an immutable reference to the underlying [Read] implementor
+    /// Get an immutable reference to the underlying [Read](std::io::Read) implementor
     pub fn inner(&self) -> &T {
         &self.reader
     }
 
-    /// Get a mutable reference to the underlying [Read] implementor
+    /// Get a mutable reference to the underlying [Read](std::io::Read) implementor
     pub fn inner_mut(&mut self) -> &mut T {
         &mut self.reader
     }
 
-    /// Consume the wrapper and return the underlying [Read] implementor
+    /// Consume the wrapper and return the underlying [Read](std::io::Read) implementor
     pub fn into_inner(self) -> T {
         self.reader
     }
@@ -75,7 +75,7 @@ impl<T: Read> Read for CountedReader<'_, T> {
     }
 }
 
-/// A wrapper for an object implementing [Write]
+/// A wrapper for an object implementing [Write](std::io::Write)
 /// which allows a closure to observe the amount of bytes written.
 /// This is useful in conjunction with metrics (e.g. [IntCounter](crate::IntCounter)).
 ///
@@ -122,17 +122,17 @@ impl<'a, T> CountedWriter<'a, T> {
         }
     }
 
-    /// Get an immutable reference to the underlying [Write] implementor
+    /// Get an immutable reference to the underlying [Write](std::io::Write) implementor
     pub fn inner(&self) -> &T {
         &self.writer
     }
 
-    /// Get a mutable reference to the underlying [Write] implementor
+    /// Get a mutable reference to the underlying [Write](std::io::Write) implementor
     pub fn inner_mut(&mut self) -> &mut T {
         &mut self.writer
     }
 
-    /// Consume the wrapper and return the underlying [Write] implementor
+    /// Consume the wrapper and return the underlying [Write](std::io::Write) implementor
     pub fn into_inner(self) -> T {
         self.writer
     }

libs/pageserver_api/src/control_api.rs

@@ -17,7 +17,7 @@ pub struct ReAttachRequest {
 pub struct ReAttachResponseTenant {
     #[serde_as(as = "DisplayFromStr")]
     pub id: TenantId,
-    pub gen: u32,
+    pub generation: u32,
 }
 
 #[derive(Serialize, Deserialize)]

libs/pageserver_api/src/models.rs

@@ -110,6 +110,7 @@ impl TenantState {
             // So, return `Maybe` while Attaching, making Console wait for the attach task to finish.
             Self::Attaching | Self::Activating(ActivatingFrom::Attaching) => Maybe,
             // tenant mgr startup distinguishes attaching from loading via marker file.
+            // If it's loading, there is no attach marker file, i.e., attach had finished in the past.
             Self::Loading | Self::Activating(ActivatingFrom::Loading) => Attached,
             // We only reach Active after successful load / attach.
             // So, call atttachment status Attached.

libs/pageserver_api/src/reltag.rs

@@ -22,9 +22,9 @@ use postgres_ffi::Oid;
 /// [See more related comments here](https:///github.com/postgres/postgres/blob/99c5852e20a0987eca1c38ba0c09329d4076b6a0/src/include/storage/relfilenode.h#L57).
 ///
 // FIXME: should move 'forknum' as last field to keep this consistent with Postgres.
-// Then we could replace the custom Ord and PartialOrd implementations below with
-// deriving them. This will require changes in walredoproc.c.
-#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy, Serialize)]
+// Then we could replace the custo Ord and PartialOrd implementations below with
+// deriving them.
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Copy, Serialize, Deserialize)]
 pub struct RelTag {
     pub forknum: u8,
     pub spcnode: Oid,
@@ -40,9 +40,21 @@ impl PartialOrd for RelTag {
 
 impl Ord for RelTag {
     fn cmp(&self, other: &Self) -> Ordering {
-        // Custom ordering where we put forknum to the end of the list
-        let other_tup = (other.spcnode, other.dbnode, other.relnode, other.forknum);
-        (self.spcnode, self.dbnode, self.relnode, self.forknum).cmp(&other_tup)
+        let mut cmp = self.spcnode.cmp(&other.spcnode);
+        if cmp != Ordering::Equal {
+            return cmp;
+        }
+        cmp = self.dbnode.cmp(&other.dbnode);
+        if cmp != Ordering::Equal {
+            return cmp;
+        }
+        cmp = self.relnode.cmp(&other.relnode);
+        if cmp != Ordering::Equal {
+            return cmp;
+        }
+        cmp = self.forknum.cmp(&other.forknum);
+
+        cmp
     }
 }
 

libs/postgres_backend/src/lib.rs

@@ -19,8 +19,8 @@ use tracing::{debug, error, info, trace};
 
 use pq_proto::framed::{ConnectionError, Framed, FramedReader, FramedWriter};
 use pq_proto::{
-    BeMessage, FeMessage, FeStartupPacket, ProtocolError, SQLSTATE_ADMIN_SHUTDOWN,
-    SQLSTATE_INTERNAL_ERROR, SQLSTATE_SUCCESSFUL_COMPLETION,
+    BeMessage, FeMessage, FeStartupPacket, ProtocolError, SQLSTATE_INTERNAL_ERROR,
+    SQLSTATE_SUCCESSFUL_COMPLETION,
 };
 
 /// An error, occurred during query processing:
@@ -30,9 +30,6 @@ pub enum QueryError {
     /// The connection was lost while processing the query.
     #[error(transparent)]
     Disconnected(#[from] ConnectionError),
-    /// We were instructed to shutdown while processing the query
-    #[error("Shutting down")]
-    Shutdown,
     /// Some other error
     #[error(transparent)]
     Other(#[from] anyhow::Error),
@@ -47,8 +44,7 @@ impl From<io::Error> for QueryError {
 impl QueryError {
     pub fn pg_error_code(&self) -> &'static [u8; 5] {
         match self {
-            Self::Disconnected(_) => b"08006", // connection failure
-            Self::Shutdown => SQLSTATE_ADMIN_SHUTDOWN,
+            Self::Disconnected(_) => b"08006",         // connection failure
             Self::Other(_) => SQLSTATE_INTERNAL_ERROR, // internal error
         }
     }
@@ -242,7 +238,6 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> MaybeWriteOnly<IO> {
         }
     }
 
-    /// Cancellation safe as long as the underlying IO is cancellation safe.
     async fn shutdown(&mut self) -> io::Result<()> {
         match self {
             MaybeWriteOnly::Full(framed) => framed.shutdown().await,
@@ -394,37 +389,14 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
         shutdown_watcher: F,
     ) -> Result<(), QueryError>
     where
-        F: Fn() -> S + Clone,
+        F: Fn() -> S,
         S: Future,
     {
-        let ret = self
-            .run_message_loop(handler, shutdown_watcher.clone())
-            .await;
-
-        tokio::select! {
-            _ = shutdown_watcher() => {
-                // do nothing; we most likely got already stopped by shutdown and will log it next.
-            }
-            _ = self.framed.shutdown() => {
-                // socket might be already closed, e.g. if previously received error,
-                // so ignore result.
-            },
-        }
-
-        match ret {
-            Ok(()) => Ok(()),
-            Err(QueryError::Shutdown) => {
-                info!("Stopped due to shutdown");
-                Ok(())
-            }
-            Err(QueryError::Disconnected(e)) => {
-                info!("Disconnected ({e:#})");
-                // Disconnection is not an error: we just use it that way internally to drop
-                // out of loops.
-                Ok(())
-            }
-            e => e,
-        }
+        let ret = self.run_message_loop(handler, shutdown_watcher).await;
+        // socket might be already closed, e.g. if previously received error,
+        // so ignore result.
+        self.framed.shutdown().await.ok();
+        ret
     }
 
     async fn run_message_loop<F, S>(
@@ -444,11 +416,15 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
             _ = shutdown_watcher() => {
                 // We were requested to shut down.
                 tracing::info!("shutdown request received during handshake");
-                return Err(QueryError::Shutdown)
+                return Ok(())
             },
 
-            handshake_r = self.handshake(handler) => {
-                handshake_r?;
+            result = self.handshake(handler) => {
+                // Handshake complete.
+                result?;
+                if self.state == ProtoState::Closed {
+                    return Ok(()); // EOF during handshake
+                }
             }
         );
 
@@ -459,7 +435,7 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
             _ = shutdown_watcher() => {
                 // We were requested to shut down.
                 tracing::info!("shutdown request received in run_message_loop");
-                return Err(QueryError::Shutdown)
+                Ok(None)
             },
             msg = self.read_message() => { msg },
         )? {
@@ -471,14 +447,7 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
                 _ = shutdown_watcher() => {
                     // We were requested to shut down.
                     tracing::info!("shutdown request received during response flush");
-
-                    // If we exited process_message with a shutdown error, there may be
-                    // some valid response content on in our transmit buffer: permit sending
-                    // this within a short timeout.  This is a best effort thing so we don't
-                    // care about the result.
-                    tokio::time::timeout(std::time::Duration::from_millis(500), self.flush()).await.ok();
-
-                    return Err(QueryError::Shutdown)
+                    return Ok(())
                 },
                 flush_r = self.flush() => {
                     flush_r?;
@@ -591,9 +560,7 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
                         self.peer_addr
                     );
                     self.state = ProtoState::Closed;
-                    return Err(QueryError::Disconnected(ConnectionError::Protocol(
-                        ProtocolError::Protocol("EOF during handshake".to_string()),
-                    )));
+                    return Ok(());
                 }
             }
         }
@@ -632,9 +599,7 @@ impl<IO: AsyncRead + AsyncWrite + Unpin> PostgresBackend<IO> {
                         self.peer_addr
                     );
                     self.state = ProtoState::Closed;
-                    return Err(QueryError::Disconnected(ConnectionError::Protocol(
-                        ProtocolError::Protocol("EOF during auth".to_string()),
-                    )));
+                    return Ok(());
                 }
             }
         }
@@ -958,7 +923,6 @@ impl<'a, IO: AsyncRead + AsyncWrite + Unpin> AsyncWrite for CopyDataWriter<'a, I
 pub fn short_error(e: &QueryError) -> String {
     match e {
         QueryError::Disconnected(connection_error) => connection_error.to_string(),
-        QueryError::Shutdown => "shutdown".to_string(),
         QueryError::Other(e) => format!("{e:#}"),
     }
 }
@@ -975,9 +939,6 @@ fn log_query_error(query: &str, e: &QueryError) {
         QueryError::Disconnected(other_connection_error) => {
             error!("query handler for '{query}' failed with connection error: {other_connection_error:?}")
         }
-        QueryError::Shutdown => {
-            info!("query handler for '{query}' cancelled during tenant shutdown")
-        }
         QueryError::Other(e) => {
             error!("query handler for '{query}' failed: {e:?}");
         }

libs/postgres_ffi/src/lib.rs

@@ -131,7 +131,6 @@ pub const MAX_SEND_SIZE: usize = XLOG_BLCKSZ * 16;
 
 // Export some version independent functions that are used outside of this mod
 pub use v14::xlog_utils::encode_logical_message;
-pub use v14::xlog_utils::from_pg_timestamp;
 pub use v14::xlog_utils::get_current_timestamp;
 pub use v14::xlog_utils::to_pg_timestamp;
 pub use v14::xlog_utils::XLogFileName;

libs/postgres_ffi/src/pg_constants.rs

@@ -220,10 +220,6 @@ pub const XLOG_CHECKPOINT_ONLINE: u8 = 0x10;
 pub const XLP_FIRST_IS_CONTRECORD: u16 = 0x0001;
 pub const XLP_LONG_HEADER: u16 = 0x0002;
 
-/* From replication/slot.h */
-pub const REPL_SLOT_ON_DISK_OFFSETOF_RESTART_LSN: usize = 4*4  /* offset of `slotdata` in ReplicationSlotOnDisk  */
-   + 64 /* NameData */  + 4*4;
-
 /* From fsm_internals.h */
 const FSM_NODES_PER_PAGE: usize = BLCKSZ as usize - SIZEOF_PAGE_HEADER_DATA - 4;
 const FSM_NON_LEAF_NODES_PER_PAGE: usize = BLCKSZ as usize / 2 - 1;

libs/postgres_ffi/src/xlog_utils.rs

@@ -136,42 +136,21 @@ pub fn get_current_timestamp() -> TimestampTz {
     to_pg_timestamp(SystemTime::now())
 }
 
-// Module to reduce the scope of the constants
-mod timestamp_conversions {
-    use std::time::Duration;
-
-    use super::*;
-
-    const UNIX_EPOCH_JDATE: u64 = 2440588; // == date2j(1970, 1, 1)
-    const POSTGRES_EPOCH_JDATE: u64 = 2451545; // == date2j(2000, 1, 1)
+pub fn to_pg_timestamp(time: SystemTime) -> TimestampTz {
+    const UNIX_EPOCH_JDATE: u64 = 2440588; /* == date2j(1970, 1, 1) */
+    const POSTGRES_EPOCH_JDATE: u64 = 2451545; /* == date2j(2000, 1, 1) */
     const SECS_PER_DAY: u64 = 86400;
     const USECS_PER_SEC: u64 = 1000000;
-    const SECS_DIFF_UNIX_TO_POSTGRES_EPOCH: u64 =
-        (POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * SECS_PER_DAY;
-
-    pub fn to_pg_timestamp(time: SystemTime) -> TimestampTz {
-        match time.duration_since(SystemTime::UNIX_EPOCH) {
-            Ok(n) => {
-                ((n.as_secs() - SECS_DIFF_UNIX_TO_POSTGRES_EPOCH) * USECS_PER_SEC
-                    + n.subsec_micros() as u64) as i64
-            }
-            Err(_) => panic!("SystemTime before UNIX EPOCH!"),
+    match time.duration_since(SystemTime::UNIX_EPOCH) {
+        Ok(n) => {
+            ((n.as_secs() - ((POSTGRES_EPOCH_JDATE - UNIX_EPOCH_JDATE) * SECS_PER_DAY))
+                * USECS_PER_SEC
+                + n.subsec_micros() as u64) as i64
         }
-    }
-
-    pub fn from_pg_timestamp(time: TimestampTz) -> SystemTime {
-        let time: u64 = time
-            .try_into()
-            .expect("timestamp before millenium (postgres epoch)");
-        let since_unix_epoch = time + SECS_DIFF_UNIX_TO_POSTGRES_EPOCH * USECS_PER_SEC;
-        SystemTime::UNIX_EPOCH
-            .checked_add(Duration::from_micros(since_unix_epoch))
-            .expect("SystemTime overflow")
+        Err(_) => panic!("SystemTime before UNIX EPOCH!"),
     }
 }
 
-pub use timestamp_conversions::{from_pg_timestamp, to_pg_timestamp};
-
 // Returns (aligned) end_lsn of the last record in data_dir with WAL segments.
 // start_lsn must point to some previously known record boundary (beginning of
 // the next record). If no valid record after is found, start_lsn is returned
@@ -502,24 +481,4 @@ pub fn encode_logical_message(prefix: &str, message: &str) -> Vec<u8> {
     wal
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_ts_conversion() {
-        let now = SystemTime::now();
-        let round_trip = from_pg_timestamp(to_pg_timestamp(now));
-
-        let now_since = now.duration_since(SystemTime::UNIX_EPOCH).unwrap();
-        let round_trip_since = round_trip.duration_since(SystemTime::UNIX_EPOCH).unwrap();
-        assert_eq!(now_since.as_micros(), round_trip_since.as_micros());
-
-        let now_pg = get_current_timestamp();
-        let round_trip_pg = to_pg_timestamp(from_pg_timestamp(now_pg));
-
-        assert_eq!(now_pg, round_trip_pg);
-    }
-
-    // If you need to craft WAL and write tests for this module, put it at wal_craft crate.
-}
+// If you need to craft WAL and write tests for this module, put it at wal_craft crate.

libs/postgres_ffi/wal_craft/src/lib.rs

@@ -14,7 +14,6 @@ macro_rules! xlog_utils_test {
     ($version:ident) => {
         #[path = "."]
         mod $version {
-            #[allow(unused_imports)]
             pub use postgres_ffi::$version::wal_craft_test_export::*;
             #[allow(clippy::duplicate_mod)]
             #[cfg(test)]

libs/pq_proto/src/framed.rs

@@ -214,24 +214,27 @@ where
     }
 }
 
-/// Cancellation safe as long as the AsyncWrite is cancellation safe.
 async fn flush<S: AsyncWrite + Unpin>(
     stream: &mut S,
     write_buf: &mut BytesMut,
 ) -> Result<(), io::Error> {
     while write_buf.has_remaining() {
-        let bytes_written = stream.write_buf(write_buf).await?;
+        let bytes_written = stream.write(write_buf.chunk()).await?;
         if bytes_written == 0 {
             return Err(io::Error::new(
                 ErrorKind::WriteZero,
                 "failed to write message",
             ));
         }
+        // The advanced part will be garbage collected, likely during shifting
+        // data left on next attempt to write to buffer when free space is not
+        // enough.
+        write_buf.advance(bytes_written);
     }
+    write_buf.clear();
     stream.flush().await
 }
 
-/// Cancellation safe as long as the AsyncWrite is cancellation safe.
 async fn shutdown<S: AsyncWrite + Unpin>(
     stream: &mut S,
     write_buf: &mut BytesMut,

libs/pq_proto/src/lib.rs

@@ -670,7 +670,6 @@ pub fn read_cstr(buf: &mut Bytes) -> Result<Bytes, ProtocolError> {
 }
 
 pub const SQLSTATE_INTERNAL_ERROR: &[u8; 5] = b"XX000";
-pub const SQLSTATE_ADMIN_SHUTDOWN: &[u8; 5] = b"57P01";
 pub const SQLSTATE_SUCCESSFUL_COMPLETION: &[u8; 5] = b"00000";
 
 impl<'a> BeMessage<'a> {

libs/remote_storage/Cargo.toml

@@ -13,7 +13,6 @@ aws-types.workspace = true
 aws-config.workspace = true
 aws-sdk-s3.workspace = true
 aws-credential-types.workspace = true
-bytes.workspace = true
 camino.workspace = true
 hyper = { workspace = true, features = ["stream"] }
 serde.workspace = true
@@ -27,13 +26,6 @@ metrics.workspace = true
 utils.workspace = true
 pin-project-lite.workspace = true
 workspace_hack.workspace = true
-azure_core.workspace = true
-azure_identity.workspace = true
-azure_storage.workspace = true
-azure_storage_blobs.workspace = true
-futures-util.workspace = true
-http-types.workspace = true
-itertools.workspace = true
 
 [dev-dependencies]
 camino-tempfile.workspace = true

libs/remote_storage/src/azure_blob.rs

@@ -1,337 +0,0 @@
-//! Azure Blob Storage wrapper
-
-use std::env;
-use std::num::NonZeroU32;
-use std::sync::Arc;
-use std::{borrow::Cow, collections::HashMap, io::Cursor};
-
-use super::REMOTE_STORAGE_PREFIX_SEPARATOR;
-use anyhow::Result;
-use azure_core::request_options::{MaxResults, Metadata, Range};
-use azure_core::Header;
-use azure_identity::DefaultAzureCredential;
-use azure_storage::StorageCredentials;
-use azure_storage_blobs::prelude::ClientBuilder;
-use azure_storage_blobs::{
-    blob::operations::GetBlobBuilder,
-    prelude::{BlobClient, ContainerClient},
-};
-use futures_util::StreamExt;
-use http_types::StatusCode;
-use tokio::io::AsyncRead;
-use tracing::debug;
-
-use crate::s3_bucket::RequestKind;
-use crate::{
-    AzureConfig, ConcurrencyLimiter, Download, DownloadError, Listing, ListingMode, RemotePath,
-    RemoteStorage, StorageMetadata,
-};
-
-pub struct AzureBlobStorage {
-    client: ContainerClient,
-    prefix_in_container: Option<String>,
-    max_keys_per_list_response: Option<NonZeroU32>,
-    concurrency_limiter: ConcurrencyLimiter,
-}
-
-impl AzureBlobStorage {
-    pub fn new(azure_config: &AzureConfig) -> Result<Self> {
-        debug!(
-            "Creating azure remote storage for azure container {}",
-            azure_config.container_name
-        );
-
-        let account = env::var("AZURE_STORAGE_ACCOUNT").expect("missing AZURE_STORAGE_ACCOUNT");
-
-        // If the `AZURE_STORAGE_ACCESS_KEY` env var has an access key, use that,
-        // otherwise try the token based credentials.
-        let credentials = if let Ok(access_key) = env::var("AZURE_STORAGE_ACCESS_KEY") {
-            StorageCredentials::access_key(account.clone(), access_key)
-        } else {
-            let token_credential = DefaultAzureCredential::default();
-            StorageCredentials::token_credential(Arc::new(token_credential))
-        };
-
-        let builder = ClientBuilder::new(account, credentials);
-
-        let client = builder.container_client(azure_config.container_name.to_owned());
-
-        let max_keys_per_list_response =
-            if let Some(limit) = azure_config.max_keys_per_list_response {
-                Some(
-                    NonZeroU32::new(limit as u32)
-                        .ok_or_else(|| anyhow::anyhow!("max_keys_per_list_response can't be 0"))?,
-                )
-            } else {
-                None
-            };
-
-        Ok(AzureBlobStorage {
-            client,
-            prefix_in_container: azure_config.prefix_in_container.to_owned(),
-            max_keys_per_list_response,
-            concurrency_limiter: ConcurrencyLimiter::new(azure_config.concurrency_limit.get()),
-        })
-    }
-
-    pub fn relative_path_to_name(&self, path: &RemotePath) -> String {
-        assert_eq!(std::path::MAIN_SEPARATOR, REMOTE_STORAGE_PREFIX_SEPARATOR);
-        let path_string = path
-            .get_path()
-            .as_str()
-            .trim_end_matches(REMOTE_STORAGE_PREFIX_SEPARATOR);
-        match &self.prefix_in_container {
-            Some(prefix) => {
-                if prefix.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
-                    prefix.clone() + path_string
-                } else {
-                    format!("{prefix}{REMOTE_STORAGE_PREFIX_SEPARATOR}{path_string}")
-                }
-            }
-            None => path_string.to_string(),
-        }
-    }
-
-    fn name_to_relative_path(&self, key: &str) -> RemotePath {
-        let relative_path =
-            match key.strip_prefix(self.prefix_in_container.as_deref().unwrap_or_default()) {
-                Some(stripped) => stripped,
-                // we rely on Azure to return properly prefixed paths
-                // for requests with a certain prefix
-                None => panic!(
-                    "Key {key} does not start with container prefix {:?}",
-                    self.prefix_in_container
-                ),
-            };
-        RemotePath(
-            relative_path
-                .split(REMOTE_STORAGE_PREFIX_SEPARATOR)
-                .collect(),
-        )
-    }
-
-    async fn download_for_builder(
-        &self,
-        metadata: StorageMetadata,
-        builder: GetBlobBuilder,
-    ) -> Result<Download, DownloadError> {
-        let mut response = builder.into_stream();
-
-        // TODO give proper streaming response instead of buffering into RAM
-        // https://github.com/neondatabase/neon/issues/5563
-        let mut buf = Vec::new();
-        while let Some(part) = response.next().await {
-            let part = part.map_err(to_download_error)?;
-            let data = part
-                .data
-                .collect()
-                .await
-                .map_err(|e| DownloadError::Other(e.into()))?;
-            buf.extend_from_slice(&data.slice(..));
-        }
-        Ok(Download {
-            download_stream: Box::pin(Cursor::new(buf)),
-            metadata: Some(metadata),
-        })
-    }
-    // TODO get rid of this function once we have metadata included in the response
-    // https://github.com/Azure/azure-sdk-for-rust/issues/1439
-    async fn get_metadata(
-        &self,
-        blob_client: &BlobClient,
-    ) -> Result<StorageMetadata, DownloadError> {
-        let builder = blob_client.get_metadata();
-
-        let response = builder.into_future().await.map_err(to_download_error)?;
-        let mut map = HashMap::new();
-
-        for md in response.metadata.iter() {
-            map.insert(
-                md.name().as_str().to_string(),
-                md.value().as_str().to_string(),
-            );
-        }
-        Ok(StorageMetadata(map))
-    }
-
-    async fn permit(&self, kind: RequestKind) -> tokio::sync::SemaphorePermit<'_> {
-        self.concurrency_limiter
-            .acquire(kind)
-            .await
-            .expect("semaphore is never closed")
-    }
-}
-
-fn to_azure_metadata(metadata: StorageMetadata) -> Metadata {
-    let mut res = Metadata::new();
-    for (k, v) in metadata.0.into_iter() {
-        res.insert(k, v);
-    }
-    res
-}
-
-fn to_download_error(error: azure_core::Error) -> DownloadError {
-    if let Some(http_err) = error.as_http_error() {
-        match http_err.status() {
-            StatusCode::NotFound => DownloadError::NotFound,
-            StatusCode::BadRequest => DownloadError::BadInput(anyhow::Error::new(error)),
-            _ => DownloadError::Other(anyhow::Error::new(error)),
-        }
-    } else {
-        DownloadError::Other(error.into())
-    }
-}
-
-#[async_trait::async_trait]
-impl RemoteStorage for AzureBlobStorage {
-    async fn list(
-        &self,
-        prefix: Option<&RemotePath>,
-        mode: ListingMode,
-    ) -> anyhow::Result<Listing, DownloadError> {
-        // get the passed prefix or if it is not set use prefix_in_bucket value
-        let list_prefix = prefix
-            .map(|p| self.relative_path_to_name(p))
-            .or_else(|| self.prefix_in_container.clone())
-            .map(|mut p| {
-                // required to end with a separator
-                // otherwise request will return only the entry of a prefix
-                if matches!(mode, ListingMode::WithDelimiter)
-                    && !p.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR)
-                {
-                    p.push(REMOTE_STORAGE_PREFIX_SEPARATOR);
-                }
-                p
-            });
-
-        let mut builder = self.client.list_blobs();
-
-        if let ListingMode::WithDelimiter = mode {
-            builder = builder.delimiter(REMOTE_STORAGE_PREFIX_SEPARATOR.to_string());
-        }
-
-        if let Some(prefix) = list_prefix {
-            builder = builder.prefix(Cow::from(prefix.to_owned()));
-        }
-
-        if let Some(limit) = self.max_keys_per_list_response {
-            builder = builder.max_results(MaxResults::new(limit));
-        }
-
-        let mut response = builder.into_stream();
-        let mut res = Listing::default();
-        while let Some(l) = response.next().await {
-            let entry = l.map_err(to_download_error)?;
-            let prefix_iter = entry
-                .blobs
-                .prefixes()
-                .map(|prefix| self.name_to_relative_path(&prefix.name));
-            res.prefixes.extend(prefix_iter);
-
-            let blob_iter = entry
-                .blobs
-                .blobs()
-                .map(|k| self.name_to_relative_path(&k.name));
-            res.keys.extend(blob_iter);
-        }
-        Ok(res)
-    }
-    async fn upload(
-        &self,
-        mut from: impl AsyncRead + Unpin + Send + Sync + 'static,
-        data_size_bytes: usize,
-        to: &RemotePath,
-        metadata: Option<StorageMetadata>,
-    ) -> anyhow::Result<()> {
-        let _permit = self.permit(RequestKind::Put).await;
-        let blob_client = self.client.blob_client(self.relative_path_to_name(to));
-
-        // TODO FIX THIS UGLY HACK and don't buffer the entire object
-        // into RAM here, but use the streaming interface. For that,
-        // we'd have to change the interface though...
-        // https://github.com/neondatabase/neon/issues/5563
-        let mut buf = Vec::with_capacity(data_size_bytes);
-        tokio::io::copy(&mut from, &mut buf).await?;
-        let body = azure_core::Body::Bytes(buf.into());
-
-        let mut builder = blob_client.put_block_blob(body);
-
-        if let Some(metadata) = metadata {
-            builder = builder.metadata(to_azure_metadata(metadata));
-        }
-
-        let _response = builder.into_future().await?;
-
-        Ok(())
-    }
-
-    async fn download(&self, from: &RemotePath) -> Result<Download, DownloadError> {
-        let _permit = self.permit(RequestKind::Get).await;
-        let blob_client = self.client.blob_client(self.relative_path_to_name(from));
-
-        let metadata = self.get_metadata(&blob_client).await?;
-
-        let builder = blob_client.get();
-
-        self.download_for_builder(metadata, builder).await
-    }
-
-    async fn download_byte_range(
-        &self,
-        from: &RemotePath,
-        start_inclusive: u64,
-        end_exclusive: Option<u64>,
-    ) -> Result<Download, DownloadError> {
-        let _permit = self.permit(RequestKind::Get).await;
-        let blob_client = self.client.blob_client(self.relative_path_to_name(from));
-
-        let metadata = self.get_metadata(&blob_client).await?;
-
-        let mut builder = blob_client.get();
-
-        if let Some(end_exclusive) = end_exclusive {
-            builder = builder.range(Range::new(start_inclusive, end_exclusive));
-        } else {
-            // Open ranges are not supported by the SDK so we work around
-            // by setting the upper limit extremely high (but high enough
-            // to still be representable by signed 64 bit integers).
-            // TODO remove workaround once the SDK adds open range support
-            // https://github.com/Azure/azure-sdk-for-rust/issues/1438
-            let end_exclusive = u64::MAX / 4;
-            builder = builder.range(Range::new(start_inclusive, end_exclusive));
-        }
-
-        self.download_for_builder(metadata, builder).await
-    }
-
-    async fn delete(&self, path: &RemotePath) -> anyhow::Result<()> {
-        let _permit = self.permit(RequestKind::Delete).await;
-        let blob_client = self.client.blob_client(self.relative_path_to_name(path));
-
-        let builder = blob_client.delete();
-
-        match builder.into_future().await {
-            Ok(_response) => Ok(()),
-            Err(e) => {
-                if let Some(http_err) = e.as_http_error() {
-                    if http_err.status() == StatusCode::NotFound {
-                        return Ok(());
-                    }
-                }
-                Err(anyhow::Error::new(e))
-            }
-        }
-    }
-
-    async fn delete_objects<'a>(&self, paths: &'a [RemotePath]) -> anyhow::Result<()> {
-        // Permit is already obtained by inner delete function
-
-        // TODO batch requests are also not supported by the SDK
-        // https://github.com/Azure/azure-sdk-for-rust/issues/1068
-        // https://github.com/Azure/azure-sdk-for-rust/issues/1249
-        for path in paths {
-            self.delete(path).await?;
-        }
-        Ok(())
-    }
-}

libs/remote_storage/src/lib.rs

@@ -4,10 +4,7 @@
 //! [`RemoteStorage`] trait a CRUD-like generic abstraction to use for adapting external storages with a few implementations:
 //!   * [`local_fs`] allows to use local file system as an external storage
 //!   * [`s3_bucket`] uses AWS S3 bucket as an external storage
-//!   * [`azure_blob`] allows to use Azure Blob storage as an external storage
 //!
-
-mod azure_blob;
 mod local_fs;
 mod s3_bucket;
 mod simulate_failures;
@@ -24,15 +21,11 @@ use anyhow::{bail, Context};
 use camino::{Utf8Path, Utf8PathBuf};
 
 use serde::{Deserialize, Serialize};
-use tokio::{io, sync::Semaphore};
+use tokio::io;
 use toml_edit::Item;
 use tracing::info;
 
-pub use self::{
-    azure_blob::AzureBlobStorage, local_fs::LocalFs, s3_bucket::S3Bucket,
-    simulate_failures::UnreliableWrapper,
-};
-use s3_bucket::RequestKind;
+pub use self::{local_fs::LocalFs, s3_bucket::S3Bucket, simulate_failures::UnreliableWrapper};
 
 /// How many different timelines can be processed simultaneously when synchronizing layers with the remote storage.
 /// During regular work, pageserver produces one layer file per timeline checkpoint, with bursts of concurrency
@@ -46,11 +39,6 @@ pub const DEFAULT_REMOTE_STORAGE_MAX_SYNC_ERRORS: u32 = 10;
 /// ~3500 PUT/COPY/POST/DELETE or 5500 GET/HEAD S3 requests
 /// <https://aws.amazon.com/premiumsupport/knowledge-center/s3-request-limit-avoid-throttling/>
 pub const DEFAULT_REMOTE_STORAGE_S3_CONCURRENCY_LIMIT: usize = 100;
-/// We set this a little bit low as we currently buffer the entire file into RAM
-///
-/// Here, a limit of max 20k concurrent connections was noted.
-/// <https://learn.microsoft.com/en-us/answers/questions/1301863/is-there-any-limitation-to-concurrent-connections>
-pub const DEFAULT_REMOTE_STORAGE_AZURE_CONCURRENCY_LIMIT: usize = 30;
 /// No limits on the client side, which currenltly means 1000 for AWS S3.
 /// <https://docs.aws.amazon.com/AmazonS3/latest/API/API_ListObjectsV2.html#API_ListObjectsV2_RequestSyntax>
 pub const DEFAULT_MAX_KEYS_PER_LIST_RESPONSE: Option<i32> = None;
@@ -129,22 +117,6 @@ impl RemotePath {
     }
 }
 
-/// We don't need callers to be able to pass arbitrary delimiters: just control
-/// whether listings will use a '/' separator or not.
-///
-/// The WithDelimiter mode will populate `prefixes` and `keys` in the result.  The
-/// NoDelimiter mode will only populate `keys`.
-pub enum ListingMode {
-    WithDelimiter,
-    NoDelimiter,
-}
-
-#[derive(Default)]
-pub struct Listing {
-    pub prefixes: Vec<RemotePath>,
-    pub keys: Vec<RemotePath>,
-}
-
 /// Storage (potentially remote) API to manage its state.
 /// This storage tries to be unaware of any layered repository context,
 /// providing basic CRUD operations for storage files.
@@ -157,13 +129,8 @@ pub trait RemoteStorage: Send + Sync + 'static {
     async fn list_prefixes(
         &self,
         prefix: Option<&RemotePath>,
-    ) -> Result<Vec<RemotePath>, DownloadError> {
-        let result = self
-            .list(prefix, ListingMode::WithDelimiter)
-            .await?
-            .prefixes;
-        Ok(result)
-    }
+    ) -> Result<Vec<RemotePath>, DownloadError>;
+
     /// Lists all files in directory "recursively"
     /// (not really recursively, because AWS has a flat namespace)
     /// Note: This is subtely different than list_prefixes,
@@ -175,16 +142,7 @@ pub trait RemoteStorage: Send + Sync + 'static {
     /// whereas,
     /// list_prefixes("foo/bar/") = ["cat", "dog"]
     /// See `test_real_s3.rs` for more details.
-    async fn list_files(&self, prefix: Option<&RemotePath>) -> anyhow::Result<Vec<RemotePath>> {
-        let result = self.list(prefix, ListingMode::NoDelimiter).await?.keys;
-        Ok(result)
-    }
-
-    async fn list(
-        &self,
-        prefix: Option<&RemotePath>,
-        _mode: ListingMode,
-    ) -> anyhow::Result<Listing, DownloadError>;
+    async fn list_files(&self, folder: Option<&RemotePath>) -> anyhow::Result<Vec<RemotePath>>;
 
     /// Streams the local file contents into remote into the remote storage entry.
     async fn upload(
@@ -235,9 +193,6 @@ pub enum DownloadError {
     BadInput(anyhow::Error),
     /// The file was not found in the remote storage.
     NotFound,
-    /// A cancellation token aborted the download, typically during
-    /// tenant detach or process shutdown.
-    Cancelled,
     /// The file was found in the remote storage, but the download failed.
     Other(anyhow::Error),
 }
@@ -248,7 +203,6 @@ impl std::fmt::Display for DownloadError {
             DownloadError::BadInput(e) => {
                 write!(f, "Failed to download a remote file due to user input: {e}")
             }
-            DownloadError::Cancelled => write!(f, "Cancelled, shutting down"),
             DownloadError::NotFound => write!(f, "No file found for the remote object id given"),
             DownloadError::Other(e) => write!(f, "Failed to download a remote file: {e:?}"),
         }
@@ -263,24 +217,10 @@ impl std::error::Error for DownloadError {}
 pub enum GenericRemoteStorage {
     LocalFs(LocalFs),
     AwsS3(Arc<S3Bucket>),
-    AzureBlob(Arc<AzureBlobStorage>),
     Unreliable(Arc<UnreliableWrapper>),
 }
 
 impl GenericRemoteStorage {
-    pub async fn list(
-        &self,
-        prefix: Option<&RemotePath>,
-        mode: ListingMode,
-    ) -> anyhow::Result<Listing, DownloadError> {
-        match self {
-            Self::LocalFs(s) => s.list(prefix, mode).await,
-            Self::AwsS3(s) => s.list(prefix, mode).await,
-            Self::AzureBlob(s) => s.list(prefix, mode).await,
-            Self::Unreliable(s) => s.list(prefix, mode).await,
-        }
-    }
-
     // A function for listing all the files in a "directory"
     // Example:
     // list_files("foo/bar") = ["foo/bar/a.txt", "foo/bar/b.txt"]
@@ -288,7 +228,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.list_files(folder).await,
             Self::AwsS3(s) => s.list_files(folder).await,
-            Self::AzureBlob(s) => s.list_files(folder).await,
             Self::Unreliable(s) => s.list_files(folder).await,
         }
     }
@@ -303,7 +242,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.list_prefixes(prefix).await,
             Self::AwsS3(s) => s.list_prefixes(prefix).await,
-            Self::AzureBlob(s) => s.list_prefixes(prefix).await,
             Self::Unreliable(s) => s.list_prefixes(prefix).await,
         }
     }
@@ -318,7 +256,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.upload(from, data_size_bytes, to, metadata).await,
             Self::AwsS3(s) => s.upload(from, data_size_bytes, to, metadata).await,
-            Self::AzureBlob(s) => s.upload(from, data_size_bytes, to, metadata).await,
             Self::Unreliable(s) => s.upload(from, data_size_bytes, to, metadata).await,
         }
     }
@@ -327,7 +264,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.download(from).await,
             Self::AwsS3(s) => s.download(from).await,
-            Self::AzureBlob(s) => s.download(from).await,
             Self::Unreliable(s) => s.download(from).await,
         }
     }
@@ -347,10 +283,6 @@ impl GenericRemoteStorage {
                 s.download_byte_range(from, start_inclusive, end_exclusive)
                     .await
             }
-            Self::AzureBlob(s) => {
-                s.download_byte_range(from, start_inclusive, end_exclusive)
-                    .await
-            }
             Self::Unreliable(s) => {
                 s.download_byte_range(from, start_inclusive, end_exclusive)
                     .await
@@ -362,7 +294,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.delete(path).await,
             Self::AwsS3(s) => s.delete(path).await,
-            Self::AzureBlob(s) => s.delete(path).await,
             Self::Unreliable(s) => s.delete(path).await,
         }
     }
@@ -371,7 +302,6 @@ impl GenericRemoteStorage {
         match self {
             Self::LocalFs(s) => s.delete_objects(paths).await,
             Self::AwsS3(s) => s.delete_objects(paths).await,
-            Self::AzureBlob(s) => s.delete_objects(paths).await,
             Self::Unreliable(s) => s.delete_objects(paths).await,
         }
     }
@@ -389,11 +319,6 @@ impl GenericRemoteStorage {
                       s3_config.bucket_name, s3_config.bucket_region, s3_config.prefix_in_bucket, s3_config.endpoint);
                 Self::AwsS3(Arc::new(S3Bucket::new(s3_config)?))
             }
-            RemoteStorageKind::AzureContainer(azure_config) => {
-                info!("Using azure container '{}' in region '{}' as a remote storage, prefix in container: '{:?}'",
-                      azure_config.container_name, azure_config.container_region, azure_config.prefix_in_container);
-                Self::AzureBlob(Arc::new(AzureBlobStorage::new(azure_config)?))
-            }
         })
     }
 
@@ -458,9 +383,6 @@ pub enum RemoteStorageKind {
     /// AWS S3 based storage, storing all files in the S3 bucket
     /// specified by the config
     AwsS3(S3Config),
-    /// Azure Blob based storage, storing all files in the container
-    /// specified by the config
-    AzureContainer(AzureConfig),
 }
 
 /// AWS S3 bucket coordinates and access credentials to manage the bucket contents (read and write).
@@ -500,45 +422,11 @@ impl Debug for S3Config {
     }
 }
 
-/// Azure  bucket coordinates and access credentials to manage the bucket contents (read and write).
-#[derive(Clone, PartialEq, Eq)]
-pub struct AzureConfig {
-    /// Name of the container to connect to.
-    pub container_name: String,
-    /// The region where the bucket is located at.
-    pub container_region: String,
-    /// A "subfolder" in the container, to use the same container separately by multiple remote storage users at once.
-    pub prefix_in_container: Option<String>,
-    /// Azure has various limits on its API calls, we need not to exceed those.
-    /// See [`DEFAULT_REMOTE_STORAGE_AZURE_CONCURRENCY_LIMIT`] for more details.
-    pub concurrency_limit: NonZeroUsize,
-    pub max_keys_per_list_response: Option<i32>,
-}
-
-impl Debug for AzureConfig {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("AzureConfig")
-            .field("bucket_name", &self.container_name)
-            .field("bucket_region", &self.container_region)
-            .field("prefix_in_bucket", &self.prefix_in_container)
-            .field("concurrency_limit", &self.concurrency_limit)
-            .field(
-                "max_keys_per_list_response",
-                &self.max_keys_per_list_response,
-            )
-            .finish()
-    }
-}
-
 impl RemoteStorageConfig {
     pub fn from_toml(toml: &toml_edit::Item) -> anyhow::Result<Option<RemoteStorageConfig>> {
         let local_path = toml.get("local_path");
         let bucket_name = toml.get("bucket_name");
         let bucket_region = toml.get("bucket_region");
-        let container_name = toml.get("container_name");
-        let container_region = toml.get("container_region");
-
-        let use_azure = container_name.is_some() && container_region.is_some();
 
         let max_concurrent_syncs = NonZeroUsize::new(
             parse_optional_integer("max_concurrent_syncs", toml)?
@@ -552,13 +440,9 @@ impl RemoteStorageConfig {
         )
         .context("Failed to parse 'max_sync_errors' as a positive integer")?;
 
-        let default_concurrency_limit = if use_azure {
-            DEFAULT_REMOTE_STORAGE_AZURE_CONCURRENCY_LIMIT
-        } else {
-            DEFAULT_REMOTE_STORAGE_S3_CONCURRENCY_LIMIT
-        };
         let concurrency_limit = NonZeroUsize::new(
-            parse_optional_integer("concurrency_limit", toml)?.unwrap_or(default_concurrency_limit),
+            parse_optional_integer("concurrency_limit", toml)?
+                .unwrap_or(DEFAULT_REMOTE_STORAGE_S3_CONCURRENCY_LIMIT),
         )
         .context("Failed to parse 'concurrency_limit' as a positive integer")?;
 
@@ -567,70 +451,33 @@ impl RemoteStorageConfig {
                 .context("Failed to parse 'max_keys_per_list_response' as a positive integer")?
                 .or(DEFAULT_MAX_KEYS_PER_LIST_RESPONSE);
 
-        let endpoint = toml
-            .get("endpoint")
-            .map(|endpoint| parse_toml_string("endpoint", endpoint))
-            .transpose()?;
-
-        let storage = match (
-            local_path,
-            bucket_name,
-            bucket_region,
-            container_name,
-            container_region,
-        ) {
+        let storage = match (local_path, bucket_name, bucket_region) {
             // no 'local_path' nor 'bucket_name' options are provided, consider this remote storage disabled
-            (None, None, None, None, None) => return Ok(None),
-            (_, Some(_), None, ..) => {
+            (None, None, None) => return Ok(None),
+            (_, Some(_), None) => {
                 bail!("'bucket_region' option is mandatory if 'bucket_name' is given ")
             }
-            (_, None, Some(_), ..) => {
+            (_, None, Some(_)) => {
                 bail!("'bucket_name' option is mandatory if 'bucket_region' is given ")
             }
-            (None, Some(bucket_name), Some(bucket_region), ..) => {
-                RemoteStorageKind::AwsS3(S3Config {
-                    bucket_name: parse_toml_string("bucket_name", bucket_name)?,
-                    bucket_region: parse_toml_string("bucket_region", bucket_region)?,
-                    prefix_in_bucket: toml
-                        .get("prefix_in_bucket")
-                        .map(|prefix_in_bucket| {
-                            parse_toml_string("prefix_in_bucket", prefix_in_bucket)
-                        })
-                        .transpose()?,
-                    endpoint,
-                    concurrency_limit,
-                    max_keys_per_list_response,
-                })
-            }
-            (_, _, _, Some(_), None) => {
-                bail!("'container_name' option is mandatory if 'container_region' is given ")
-            }
-            (_, _, _, None, Some(_)) => {
-                bail!("'container_name' option is mandatory if 'container_region' is given ")
-            }
-            (None, None, None, Some(container_name), Some(container_region)) => {
-                RemoteStorageKind::AzureContainer(AzureConfig {
-                    container_name: parse_toml_string("container_name", container_name)?,
-                    container_region: parse_toml_string("container_region", container_region)?,
-                    prefix_in_container: toml
-                        .get("prefix_in_container")
-                        .map(|prefix_in_container| {
-                            parse_toml_string("prefix_in_container", prefix_in_container)
-                        })
-                        .transpose()?,
-                    concurrency_limit,
-                    max_keys_per_list_response,
-                })
-            }
-            (Some(local_path), None, None, None, None) => RemoteStorageKind::LocalFs(
-                Utf8PathBuf::from(parse_toml_string("local_path", local_path)?),
-            ),
-            (Some(_), Some(_), ..) => {
-                bail!("'local_path' and 'bucket_name' are mutually exclusive")
-            }
-            (Some(_), _, _, Some(_), Some(_)) => {
-                bail!("local_path and 'container_name' are mutually exclusive")
-            }
+            (None, Some(bucket_name), Some(bucket_region)) => RemoteStorageKind::AwsS3(S3Config {
+                bucket_name: parse_toml_string("bucket_name", bucket_name)?,
+                bucket_region: parse_toml_string("bucket_region", bucket_region)?,
+                prefix_in_bucket: toml
+                    .get("prefix_in_bucket")
+                    .map(|prefix_in_bucket| parse_toml_string("prefix_in_bucket", prefix_in_bucket))
+                    .transpose()?,
+                endpoint: toml
+                    .get("endpoint")
+                    .map(|endpoint| parse_toml_string("endpoint", endpoint))
+                    .transpose()?,
+                concurrency_limit,
+                max_keys_per_list_response,
+            }),
+            (Some(local_path), None, None) => RemoteStorageKind::LocalFs(Utf8PathBuf::from(
+                parse_toml_string("local_path", local_path)?,
+            )),
+            (Some(_), Some(_), _) => bail!("local_path and bucket_name are mutually exclusive"),
         };
 
         Ok(Some(RemoteStorageConfig {
@@ -666,46 +513,6 @@ fn parse_toml_string(name: &str, item: &Item) -> anyhow::Result<String> {
     Ok(s.to_string())
 }
 
-struct ConcurrencyLimiter {
-    // Every request to S3 can be throttled or cancelled, if a certain number of requests per second is exceeded.
-    // Same goes to IAM, which is queried before every S3 request, if enabled. IAM has even lower RPS threshold.
-    // The helps to ensure we don't exceed the thresholds.
-    write: Arc<Semaphore>,
-    read: Arc<Semaphore>,
-}
-
-impl ConcurrencyLimiter {
-    fn for_kind(&self, kind: RequestKind) -> &Arc<Semaphore> {
-        match kind {
-            RequestKind::Get => &self.read,
-            RequestKind::Put => &self.write,
-            RequestKind::List => &self.read,
-            RequestKind::Delete => &self.write,
-        }
-    }
-
-    async fn acquire(
-        &self,
-        kind: RequestKind,
-    ) -> Result<tokio::sync::SemaphorePermit<'_>, tokio::sync::AcquireError> {
-        self.for_kind(kind).acquire().await
-    }
-
-    async fn acquire_owned(
-        &self,
-        kind: RequestKind,
-    ) -> Result<tokio::sync::OwnedSemaphorePermit, tokio::sync::AcquireError> {
-        Arc::clone(self.for_kind(kind)).acquire_owned().await
-    }
-
-    fn new(limit: usize) -> ConcurrencyLimiter {
-        Self {
-            read: Arc::new(Semaphore::new(limit)),
-            write: Arc::new(Semaphore::new(limit)),
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

libs/remote_storage/src/local_fs.rs

@@ -15,7 +15,7 @@ use tokio::{
 use tracing::*;
 use utils::{crashsafe::path_with_suffix_extension, fs_ext::is_directory_empty};
 
-use crate::{Download, DownloadError, Listing, ListingMode, RemotePath};
+use crate::{Download, DownloadError, RemotePath};
 
 use super::{RemoteStorage, StorageMetadata};
 
@@ -75,7 +75,7 @@ impl LocalFs {
     }
 
     #[cfg(test)]
-    async fn list_all(&self) -> anyhow::Result<Vec<RemotePath>> {
+    async fn list(&self) -> anyhow::Result<Vec<RemotePath>> {
         Ok(get_all_files(&self.storage_root, true)
             .await?
             .into_iter()
@@ -89,10 +89,52 @@ impl LocalFs {
             })
             .collect())
     }
+}
+
+#[async_trait::async_trait]
+impl RemoteStorage for LocalFs {
+    async fn list_prefixes(
+        &self,
+        prefix: Option<&RemotePath>,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        let path = match prefix {
+            Some(prefix) => Cow::Owned(prefix.with_base(&self.storage_root)),
+            None => Cow::Borrowed(&self.storage_root),
+        };
+
+        let prefixes_to_filter = get_all_files(path.as_ref(), false)
+            .await
+            .map_err(DownloadError::Other)?;
+
+        let mut prefixes = Vec::with_capacity(prefixes_to_filter.len());
+
+        // filter out empty directories to mirror s3 behavior.
+        for prefix in prefixes_to_filter {
+            if prefix.is_dir()
+                && is_directory_empty(&prefix)
+                    .await
+                    .map_err(DownloadError::Other)?
+            {
+                continue;
+            }
+
+            prefixes.push(
+                prefix
+                    .strip_prefix(&self.storage_root)
+                    .context("Failed to strip prefix")
+                    .and_then(RemotePath::new)
+                    .expect(
+                        "We list files for storage root, hence should be able to remote the prefix",
+                    ),
+            )
+        }
+
+        Ok(prefixes)
+    }
 
     // recursively lists all files in a directory,
     // mirroring the `list_files` for `s3_bucket`
-    async fn list_recursive(&self, folder: Option<&RemotePath>) -> anyhow::Result<Vec<RemotePath>> {
+    async fn list_files(&self, folder: Option<&RemotePath>) -> anyhow::Result<Vec<RemotePath>> {
         let full_path = match folder {
             Some(folder) => folder.with_base(&self.storage_root),
             None => self.storage_root.clone(),
@@ -144,70 +186,6 @@ impl LocalFs {
 
         Ok(files)
     }
-}
-
-#[async_trait::async_trait]
-impl RemoteStorage for LocalFs {
-    async fn list(
-        &self,
-        prefix: Option<&RemotePath>,
-        mode: ListingMode,
-    ) -> Result<Listing, DownloadError> {
-        let mut result = Listing::default();
-
-        if let ListingMode::NoDelimiter = mode {
-            let keys = self
-                .list_recursive(prefix)
-                .await
-                .map_err(DownloadError::Other)?;
-
-            result.keys = keys
-                .into_iter()
-                .filter(|k| {
-                    let path = k.with_base(&self.storage_root);
-                    !path.is_dir()
-                })
-                .collect();
-
-            return Ok(result);
-        }
-
-        let path = match prefix {
-            Some(prefix) => Cow::Owned(prefix.with_base(&self.storage_root)),
-            None => Cow::Borrowed(&self.storage_root),
-        };
-
-        let prefixes_to_filter = get_all_files(path.as_ref(), false)
-            .await
-            .map_err(DownloadError::Other)?;
-
-        // filter out empty directories to mirror s3 behavior.
-        for prefix in prefixes_to_filter {
-            if prefix.is_dir()
-                && is_directory_empty(&prefix)
-                    .await
-                    .map_err(DownloadError::Other)?
-            {
-                continue;
-            }
-
-            let stripped = prefix
-                .strip_prefix(&self.storage_root)
-                .context("Failed to strip prefix")
-                .and_then(RemotePath::new)
-                .expect(
-                    "We list files for storage root, hence should be able to remote the prefix",
-                );
-
-            if prefix.is_dir() {
-                result.prefixes.push(stripped);
-            } else {
-                result.keys.push(stripped);
-            }
-        }
-
-        Ok(result)
-    }
 
     async fn upload(
         &self,
@@ -501,7 +479,7 @@ mod fs_tests {
 
         let target_path_1 = upload_dummy_file(&storage, "upload_1", None).await?;
         assert_eq!(
-            storage.list_all().await?,
+            storage.list().await?,
             vec![target_path_1.clone()],
             "Should list a single file after first upload"
         );
@@ -689,7 +667,7 @@ mod fs_tests {
         let upload_target = upload_dummy_file(&storage, upload_name, None).await?;
 
         storage.delete(&upload_target).await?;
-        assert!(storage.list_all().await?.is_empty());
+        assert!(storage.list().await?.is_empty());
 
         storage
             .delete(&upload_target)
@@ -747,43 +725,6 @@ mod fs_tests {
         Ok(())
     }
 
-    #[tokio::test]
-    async fn list() -> anyhow::Result<()> {
-        // No delimiter: should recursively list everything
-        let storage = create_storage()?;
-        let child = upload_dummy_file(&storage, "grandparent/parent/child", None).await?;
-        let uncle = upload_dummy_file(&storage, "grandparent/uncle", None).await?;
-
-        let listing = storage.list(None, ListingMode::NoDelimiter).await?;
-        assert!(listing.prefixes.is_empty());
-        assert_eq!(listing.keys, [uncle.clone(), child.clone()].to_vec());
-
-        // Delimiter: should only go one deep
-        let listing = storage.list(None, ListingMode::WithDelimiter).await?;
-
-        assert_eq!(
-            listing.prefixes,
-            [RemotePath::from_string("timelines").unwrap()].to_vec()
-        );
-        assert!(listing.keys.is_empty());
-
-        // Delimiter & prefix
-        let listing = storage
-            .list(
-                Some(&RemotePath::from_string("timelines/some_timeline/grandparent").unwrap()),
-                ListingMode::WithDelimiter,
-            )
-            .await?;
-        assert_eq!(
-            listing.prefixes,
-            [RemotePath::from_string("timelines/some_timeline/grandparent/parent").unwrap()]
-                .to_vec()
-        );
-        assert_eq!(listing.keys, [uncle.clone()].to_vec());
-
-        Ok(())
-    }
-
     async fn upload_dummy_file(
         storage: &LocalFs,
         name: &str,
@@ -836,7 +777,7 @@ mod fs_tests {
     }
 
     async fn list_files_sorted(storage: &LocalFs) -> anyhow::Result<Vec<RemotePath>> {
-        let mut files = storage.list_all().await?;
+        let mut files = storage.list().await?;
         files.sort_by(|a, b| a.0.cmp(&b.0));
         Ok(files)
     }

libs/remote_storage/src/s3_bucket.rs

@@ -4,7 +4,7 @@
 //! allowing multiple api users to independently work with the same S3 bucket, if
 //! their bucket prefixes are both specified and different.
 
-use std::borrow::Cow;
+use std::{borrow::Cow, sync::Arc};
 
 use anyhow::Context;
 use aws_config::{
@@ -24,20 +24,22 @@ use aws_sdk_s3::{
 use aws_smithy_http::body::SdkBody;
 use hyper::Body;
 use scopeguard::ScopeGuard;
-use tokio::io::{self, AsyncRead};
+use tokio::{
+    io::{self, AsyncRead},
+    sync::Semaphore,
+};
 use tokio_util::io::ReaderStream;
 use tracing::debug;
 
 use super::StorageMetadata;
 use crate::{
-    ConcurrencyLimiter, Download, DownloadError, Listing, ListingMode, RemotePath, RemoteStorage,
-    S3Config, MAX_KEYS_PER_DELETE, REMOTE_STORAGE_PREFIX_SEPARATOR,
+    Download, DownloadError, RemotePath, RemoteStorage, S3Config, MAX_KEYS_PER_DELETE,
+    REMOTE_STORAGE_PREFIX_SEPARATOR,
 };
 
 pub(super) mod metrics;
 
-use self::metrics::AttemptOutcome;
-pub(super) use self::metrics::RequestKind;
+use self::metrics::{AttemptOutcome, RequestKind};
 
 /// AWS S3 storage.
 pub struct S3Bucket {
@@ -48,6 +50,46 @@ pub struct S3Bucket {
     concurrency_limiter: ConcurrencyLimiter,
 }
 
+struct ConcurrencyLimiter {
+    // Every request to S3 can be throttled or cancelled, if a certain number of requests per second is exceeded.
+    // Same goes to IAM, which is queried before every S3 request, if enabled. IAM has even lower RPS threshold.
+    // The helps to ensure we don't exceed the thresholds.
+    write: Arc<Semaphore>,
+    read: Arc<Semaphore>,
+}
+
+impl ConcurrencyLimiter {
+    fn for_kind(&self, kind: RequestKind) -> &Arc<Semaphore> {
+        match kind {
+            RequestKind::Get => &self.read,
+            RequestKind::Put => &self.write,
+            RequestKind::List => &self.read,
+            RequestKind::Delete => &self.write,
+        }
+    }
+
+    async fn acquire(
+        &self,
+        kind: RequestKind,
+    ) -> Result<tokio::sync::SemaphorePermit<'_>, tokio::sync::AcquireError> {
+        self.for_kind(kind).acquire().await
+    }
+
+    async fn acquire_owned(
+        &self,
+        kind: RequestKind,
+    ) -> Result<tokio::sync::OwnedSemaphorePermit, tokio::sync::AcquireError> {
+        Arc::clone(self.for_kind(kind)).acquire_owned().await
+    }
+
+    fn new(limit: usize) -> ConcurrencyLimiter {
+        Self {
+            read: Arc::new(Semaphore::new(limit)),
+            write: Arc::new(Semaphore::new(limit)),
+        }
+    }
+}
+
 #[derive(Default)]
 struct GetObjectRequest {
     bucket: String,
@@ -299,13 +341,13 @@ impl<S: AsyncRead> AsyncRead for TimedDownload<S> {
 
 #[async_trait::async_trait]
 impl RemoteStorage for S3Bucket {
-    async fn list(
+    /// See the doc for `RemoteStorage::list_prefixes`
+    /// Note: it wont include empty "directories"
+    async fn list_prefixes(
         &self,
         prefix: Option<&RemotePath>,
-        mode: ListingMode,
-    ) -> Result<Listing, DownloadError> {
+    ) -> Result<Vec<RemotePath>, DownloadError> {
         let kind = RequestKind::List;
-        let mut result = Listing::default();
 
         // get the passed prefix or if it is not set use prefix_in_bucket value
         let list_prefix = prefix
@@ -314,33 +356,28 @@ impl RemoteStorage for S3Bucket {
             .map(|mut p| {
                 // required to end with a separator
                 // otherwise request will return only the entry of a prefix
-                if matches!(mode, ListingMode::WithDelimiter)
-                    && !p.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR)
-                {
+                if !p.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
                     p.push(REMOTE_STORAGE_PREFIX_SEPARATOR);
                 }
                 p
             });
 
+        let mut document_keys = Vec::new();
+
         let mut continuation_token = None;
 
         loop {
             let _guard = self.permit(kind).await;
             let started_at = start_measuring_requests(kind);
 
-            let mut request = self
+            let fetch_response = self
                 .client
                 .list_objects_v2()
                 .bucket(self.bucket_name.clone())
                 .set_prefix(list_prefix.clone())
                 .set_continuation_token(continuation_token)
-                .set_max_keys(self.max_keys_per_list_response);
-
-            if let ListingMode::WithDelimiter = mode {
-                request = request.delimiter(REMOTE_STORAGE_PREFIX_SEPARATOR.to_string());
-            }
-
-            let response = request
+                .delimiter(REMOTE_STORAGE_PREFIX_SEPARATOR.to_string())
+                .set_max_keys(self.max_keys_per_list_response)
                 .send()
                 .await
                 .context("Failed to list S3 prefixes")
@@ -350,35 +387,71 @@ impl RemoteStorage for S3Bucket {
 
             metrics::BUCKET_METRICS
                 .req_seconds
-                .observe_elapsed(kind, &response, started_at);
+                .observe_elapsed(kind, &fetch_response, started_at);
 
-            let response = response?;
+            let fetch_response = fetch_response?;
 
-            let keys = response.contents().unwrap_or_default();
-            let empty = Vec::new();
-            let prefixes = response.common_prefixes.as_ref().unwrap_or(&empty);
-
-            tracing::info!("list: {} prefixes, {} keys", prefixes.len(), keys.len());
-
-            for object in keys {
-                let object_path = object.key().expect("response does not contain a key");
-                let remote_path = self.s3_object_to_relative_path(object_path);
-                result.keys.push(remote_path);
-            }
-
-            result.prefixes.extend(
-                prefixes
-                    .iter()
+            document_keys.extend(
+                fetch_response
+                    .common_prefixes
+                    .unwrap_or_default()
+                    .into_iter()
                     .filter_map(|o| Some(self.s3_object_to_relative_path(o.prefix()?))),
             );
 
-            continuation_token = match response.next_continuation_token {
+            continuation_token = match fetch_response.next_continuation_token {
                 Some(new_token) => Some(new_token),
                 None => break,
             };
         }
 
-        Ok(result)
+        Ok(document_keys)
+    }
+
+    /// See the doc for `RemoteStorage::list_files`
+    async fn list_files(&self, folder: Option<&RemotePath>) -> anyhow::Result<Vec<RemotePath>> {
+        let kind = RequestKind::List;
+
+        let folder_name = folder
+            .map(|p| self.relative_path_to_s3_object(p))
+            .or_else(|| self.prefix_in_bucket.clone());
+
+        // AWS may need to break the response into several parts
+        let mut continuation_token = None;
+        let mut all_files = vec![];
+        loop {
+            let _guard = self.permit(kind).await;
+            let started_at = start_measuring_requests(kind);
+
+            let response = self
+                .client
+                .list_objects_v2()
+                .bucket(self.bucket_name.clone())
+                .set_prefix(folder_name.clone())
+                .set_continuation_token(continuation_token)
+                .set_max_keys(self.max_keys_per_list_response)
+                .send()
+                .await
+                .context("Failed to list files in S3 bucket");
+
+            let started_at = ScopeGuard::into_inner(started_at);
+            metrics::BUCKET_METRICS
+                .req_seconds
+                .observe_elapsed(kind, &response, started_at);
+
+            let response = response?;
+
+            for object in response.contents().unwrap_or_default() {
+                let object_path = object.key().expect("response does not contain a key");
+                let remote_path = self.s3_object_to_relative_path(object_path);
+                all_files.push(remote_path);
+            }
+            match response.next_continuation_token {
+                Some(new_token) => continuation_token = Some(new_token),
+                None => break,
+            }
+        }
+        Ok(all_files)
     }
 
     async fn upload(

libs/remote_storage/src/s3_bucket/metrics.rs

@@ -6,7 +6,7 @@ use once_cell::sync::Lazy;
 pub(super) static BUCKET_METRICS: Lazy<BucketMetrics> = Lazy::new(Default::default);
 
 #[derive(Clone, Copy, Debug)]
-pub(crate) enum RequestKind {
+pub(super) enum RequestKind {
     Get = 0,
     Put = 1,
     Delete = 2,

libs/remote_storage/src/simulate_failures.rs

@@ -5,9 +5,7 @@ use std::collections::hash_map::Entry;
 use std::collections::HashMap;
 use std::sync::Mutex;
 
-use crate::{
-    Download, DownloadError, Listing, ListingMode, RemotePath, RemoteStorage, StorageMetadata,
-};
+use crate::{Download, DownloadError, RemotePath, RemoteStorage, StorageMetadata};
 
 pub struct UnreliableWrapper {
     inner: crate::GenericRemoteStorage,
@@ -97,15 +95,6 @@ impl RemoteStorage for UnreliableWrapper {
         self.inner.list_files(folder).await
     }
 
-    async fn list(
-        &self,
-        prefix: Option<&RemotePath>,
-        mode: ListingMode,
-    ) -> Result<Listing, DownloadError> {
-        self.attempt(RemoteOp::ListPrefixes(prefix.cloned()))?;
-        self.inner.list(prefix, mode).await
-    }
-
     async fn upload(
         &self,
         data: impl tokio::io::AsyncRead + Unpin + Send + Sync + 'static,

libs/remote_storage/tests/test_real_azure.rs

@@ -1,625 +0,0 @@
-use std::collections::HashSet;
-use std::env;
-use std::num::{NonZeroU32, NonZeroUsize};
-use std::ops::ControlFlow;
-use std::path::PathBuf;
-use std::sync::Arc;
-use std::time::UNIX_EPOCH;
-
-use anyhow::Context;
-use camino::Utf8Path;
-use once_cell::sync::OnceCell;
-use remote_storage::{
-    AzureConfig, Download, GenericRemoteStorage, RemotePath, RemoteStorageConfig, RemoteStorageKind,
-};
-use test_context::{test_context, AsyncTestContext};
-use tokio::task::JoinSet;
-use tracing::{debug, error, info};
-
-static LOGGING_DONE: OnceCell<()> = OnceCell::new();
-
-const ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME: &str = "ENABLE_REAL_AZURE_REMOTE_STORAGE";
-
-const BASE_PREFIX: &str = "test";
-
-/// Tests that the Azure client can list all prefixes, even if the response comes paginated and requires multiple HTTP queries.
-/// Uses real Azure and requires [`ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME`] and related Azure cred env vars specified.
-/// See the client creation in [`create_azure_client`] for details on the required env vars.
-/// If real Azure tests are disabled, the test passes, skipping any real test run: currently, there's no way to mark the test ignored in runtime with the
-/// deafult test framework, see https://github.com/rust-lang/rust/issues/68007 for details.
-///
-/// First, the test creates a set of Azure blobs with keys `/${random_prefix_part}/${base_prefix_str}/sub_prefix_${i}/blob_${i}` in [`upload_azure_data`]
-/// where
-/// * `random_prefix_part` is set for the entire Azure client during the Azure client creation in [`create_azure_client`], to avoid multiple test runs interference
-/// * `base_prefix_str` is a common prefix to use in the client requests: we would want to ensure that the client is able to list nested prefixes inside the bucket
-///
-/// Then, verifies that the client does return correct prefixes when queried:
-/// * with no prefix, it lists everything after its `${random_prefix_part}/` — that should be `${base_prefix_str}` value only
-/// * with `${base_prefix_str}/` prefix, it lists every `sub_prefix_${i}`
-///
-/// With the real Azure enabled and `#[cfg(test)]` Rust configuration used, the Azure client test adds a `max-keys` param to limit the response keys.
-/// This way, we are able to test the pagination implicitly, by ensuring all results are returned from the remote storage and avoid uploading too many blobs to Azure.
-///
-/// Lastly, the test attempts to clean up and remove all uploaded Azure files.
-/// If any errors appear during the clean up, they get logged, but the test is not failed or stopped until clean up is finished.
-#[test_context(MaybeEnabledAzureWithTestBlobs)]
-#[tokio::test]
-async fn azure_pagination_should_work(
-    ctx: &mut MaybeEnabledAzureWithTestBlobs,
-) -> anyhow::Result<()> {
-    let ctx = match ctx {
-        MaybeEnabledAzureWithTestBlobs::Enabled(ctx) => ctx,
-        MaybeEnabledAzureWithTestBlobs::Disabled => return Ok(()),
-        MaybeEnabledAzureWithTestBlobs::UploadsFailed(e, _) => {
-            anyhow::bail!("Azure init failed: {e:?}")
-        }
-    };
-
-    let test_client = Arc::clone(&ctx.enabled.client);
-    let expected_remote_prefixes = ctx.remote_prefixes.clone();
-
-    let base_prefix = RemotePath::new(Utf8Path::new(ctx.enabled.base_prefix))
-        .context("common_prefix construction")?;
-    let root_remote_prefixes = test_client
-        .list_prefixes(None)
-        .await
-        .context("client list root prefixes failure")?
-        .into_iter()
-        .collect::<HashSet<_>>();
-    assert_eq!(
-        root_remote_prefixes, HashSet::from([base_prefix.clone()]),
-        "remote storage root prefixes list mismatches with the uploads. Returned prefixes: {root_remote_prefixes:?}"
-    );
-
-    let nested_remote_prefixes = test_client
-        .list_prefixes(Some(&base_prefix))
-        .await
-        .context("client list nested prefixes failure")?
-        .into_iter()
-        .collect::<HashSet<_>>();
-    let remote_only_prefixes = nested_remote_prefixes
-        .difference(&expected_remote_prefixes)
-        .collect::<HashSet<_>>();
-    let missing_uploaded_prefixes = expected_remote_prefixes
-        .difference(&nested_remote_prefixes)
-        .collect::<HashSet<_>>();
-    assert_eq!(
-        remote_only_prefixes.len() + missing_uploaded_prefixes.len(), 0,
-        "remote storage nested prefixes list mismatches with the uploads. Remote only prefixes: {remote_only_prefixes:?}, missing uploaded prefixes: {missing_uploaded_prefixes:?}",
-    );
-
-    Ok(())
-}
-
-/// Tests that Azure client can list all files in a folder, even if the response comes paginated and requirees multiple Azure queries.
-/// Uses real Azure and requires [`ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME`] and related Azure cred env vars specified. Test will skip real code and pass if env vars not set.
-/// See `Azure_pagination_should_work` for more information.
-///
-/// First, create a set of Azure objects with keys `random_prefix/folder{j}/blob_{i}.txt` in [`upload_azure_data`]
-/// Then performs the following queries:
-///    1. `list_files(None)`. This should return all files `random_prefix/folder{j}/blob_{i}.txt`
-///    2. `list_files("folder1")`.  This  should return all files `random_prefix/folder1/blob_{i}.txt`
-#[test_context(MaybeEnabledAzureWithSimpleTestBlobs)]
-#[tokio::test]
-async fn azure_list_files_works(
-    ctx: &mut MaybeEnabledAzureWithSimpleTestBlobs,
-) -> anyhow::Result<()> {
-    let ctx = match ctx {
-        MaybeEnabledAzureWithSimpleTestBlobs::Enabled(ctx) => ctx,
-        MaybeEnabledAzureWithSimpleTestBlobs::Disabled => return Ok(()),
-        MaybeEnabledAzureWithSimpleTestBlobs::UploadsFailed(e, _) => {
-            anyhow::bail!("Azure init failed: {e:?}")
-        }
-    };
-    let test_client = Arc::clone(&ctx.enabled.client);
-    let base_prefix =
-        RemotePath::new(Utf8Path::new("folder1")).context("common_prefix construction")?;
-    let root_files = test_client
-        .list_files(None)
-        .await
-        .context("client list root files failure")?
-        .into_iter()
-        .collect::<HashSet<_>>();
-    assert_eq!(
-        root_files,
-        ctx.remote_blobs.clone(),
-        "remote storage list_files on root mismatches with the uploads."
-    );
-    let nested_remote_files = test_client
-        .list_files(Some(&base_prefix))
-        .await
-        .context("client list nested files failure")?
-        .into_iter()
-        .collect::<HashSet<_>>();
-    let trim_remote_blobs: HashSet<_> = ctx
-        .remote_blobs
-        .iter()
-        .map(|x| x.get_path())
-        .filter(|x| x.starts_with("folder1"))
-        .map(|x| RemotePath::new(x).expect("must be valid path"))
-        .collect();
-    assert_eq!(
-        nested_remote_files, trim_remote_blobs,
-        "remote storage list_files on subdirrectory mismatches with the uploads."
-    );
-    Ok(())
-}
-
-#[test_context(MaybeEnabledAzure)]
-#[tokio::test]
-async fn azure_delete_non_exising_works(ctx: &mut MaybeEnabledAzure) -> anyhow::Result<()> {
-    let ctx = match ctx {
-        MaybeEnabledAzure::Enabled(ctx) => ctx,
-        MaybeEnabledAzure::Disabled => return Ok(()),
-    };
-
-    let path = RemotePath::new(Utf8Path::new(
-        format!("{}/for_sure_there_is_nothing_there_really", ctx.base_prefix).as_str(),
-    ))
-    .with_context(|| "RemotePath conversion")?;
-
-    ctx.client.delete(&path).await.expect("should succeed");
-
-    Ok(())
-}
-
-#[test_context(MaybeEnabledAzure)]
-#[tokio::test]
-async fn azure_delete_objects_works(ctx: &mut MaybeEnabledAzure) -> anyhow::Result<()> {
-    let ctx = match ctx {
-        MaybeEnabledAzure::Enabled(ctx) => ctx,
-        MaybeEnabledAzure::Disabled => return Ok(()),
-    };
-
-    let path1 = RemotePath::new(Utf8Path::new(format!("{}/path1", ctx.base_prefix).as_str()))
-        .with_context(|| "RemotePath conversion")?;
-
-    let path2 = RemotePath::new(Utf8Path::new(format!("{}/path2", ctx.base_prefix).as_str()))
-        .with_context(|| "RemotePath conversion")?;
-
-    let path3 = RemotePath::new(Utf8Path::new(format!("{}/path3", ctx.base_prefix).as_str()))
-        .with_context(|| "RemotePath conversion")?;
-
-    let data1 = "remote blob data1".as_bytes();
-    let data1_len = data1.len();
-    let data2 = "remote blob data2".as_bytes();
-    let data2_len = data2.len();
-    let data3 = "remote blob data3".as_bytes();
-    let data3_len = data3.len();
-    ctx.client
-        .upload(std::io::Cursor::new(data1), data1_len, &path1, None)
-        .await?;
-
-    ctx.client
-        .upload(std::io::Cursor::new(data2), data2_len, &path2, None)
-        .await?;
-
-    ctx.client
-        .upload(std::io::Cursor::new(data3), data3_len, &path3, None)
-        .await?;
-
-    ctx.client.delete_objects(&[path1, path2]).await?;
-
-    let prefixes = ctx.client.list_prefixes(None).await?;
-
-    assert_eq!(prefixes.len(), 1);
-
-    ctx.client.delete_objects(&[path3]).await?;
-
-    Ok(())
-}
-
-#[test_context(MaybeEnabledAzure)]
-#[tokio::test]
-async fn azure_upload_download_works(ctx: &mut MaybeEnabledAzure) -> anyhow::Result<()> {
-    let MaybeEnabledAzure::Enabled(ctx) = ctx else {
-        return Ok(());
-    };
-
-    let path = RemotePath::new(Utf8Path::new(format!("{}/file", ctx.base_prefix).as_str()))
-        .with_context(|| "RemotePath conversion")?;
-
-    let data = "remote blob data here".as_bytes();
-    let data_len = data.len() as u64;
-
-    ctx.client
-        .upload(std::io::Cursor::new(data), data.len(), &path, None)
-        .await?;
-
-    async fn download_and_compare(mut dl: Download) -> anyhow::Result<Vec<u8>> {
-        let mut buf = Vec::new();
-        tokio::io::copy(&mut dl.download_stream, &mut buf).await?;
-        Ok(buf)
-    }
-    // Normal download request
-    let dl = ctx.client.download(&path).await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data);
-
-    // Full range (end specified)
-    let dl = ctx
-        .client
-        .download_byte_range(&path, 0, Some(data_len))
-        .await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data);
-
-    // partial range (end specified)
-    let dl = ctx.client.download_byte_range(&path, 4, Some(10)).await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data[4..10]);
-
-    // partial range (end beyond real end)
-    let dl = ctx
-        .client
-        .download_byte_range(&path, 8, Some(data_len * 100))
-        .await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data[8..]);
-
-    // Partial range (end unspecified)
-    let dl = ctx.client.download_byte_range(&path, 4, None).await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data[4..]);
-
-    // Full range (end unspecified)
-    let dl = ctx.client.download_byte_range(&path, 0, None).await?;
-    let buf = download_and_compare(dl).await?;
-    assert_eq!(buf, data);
-
-    debug!("Cleanup: deleting file at path {path:?}");
-    ctx.client
-        .delete(&path)
-        .await
-        .with_context(|| format!("{path:?} removal"))?;
-
-    Ok(())
-}
-
-fn ensure_logging_ready() {
-    LOGGING_DONE.get_or_init(|| {
-        utils::logging::init(
-            utils::logging::LogFormat::Test,
-            utils::logging::TracingErrorLayerEnablement::Disabled,
-        )
-        .expect("logging init failed");
-    });
-}
-
-struct EnabledAzure {
-    client: Arc<GenericRemoteStorage>,
-    base_prefix: &'static str,
-}
-
-impl EnabledAzure {
-    async fn setup(max_keys_in_list_response: Option<i32>) -> Self {
-        let client = create_azure_client(max_keys_in_list_response)
-            .context("Azure client creation")
-            .expect("Azure client creation failed");
-
-        EnabledAzure {
-            client,
-            base_prefix: BASE_PREFIX,
-        }
-    }
-}
-
-enum MaybeEnabledAzure {
-    Enabled(EnabledAzure),
-    Disabled,
-}
-
-#[async_trait::async_trait]
-impl AsyncTestContext for MaybeEnabledAzure {
-    async fn setup() -> Self {
-        ensure_logging_ready();
-
-        if env::var(ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME).is_err() {
-            info!(
-                "`{}` env variable is not set, skipping the test",
-                ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME
-            );
-            return Self::Disabled;
-        }
-
-        Self::Enabled(EnabledAzure::setup(None).await)
-    }
-}
-
-enum MaybeEnabledAzureWithTestBlobs {
-    Enabled(AzureWithTestBlobs),
-    Disabled,
-    UploadsFailed(anyhow::Error, AzureWithTestBlobs),
-}
-
-struct AzureWithTestBlobs {
-    enabled: EnabledAzure,
-    remote_prefixes: HashSet<RemotePath>,
-    remote_blobs: HashSet<RemotePath>,
-}
-
-#[async_trait::async_trait]
-impl AsyncTestContext for MaybeEnabledAzureWithTestBlobs {
-    async fn setup() -> Self {
-        ensure_logging_ready();
-        if env::var(ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME).is_err() {
-            info!(
-                "`{}` env variable is not set, skipping the test",
-                ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME
-            );
-            return Self::Disabled;
-        }
-
-        let max_keys_in_list_response = 10;
-        let upload_tasks_count = 1 + (2 * usize::try_from(max_keys_in_list_response).unwrap());
-
-        let enabled = EnabledAzure::setup(Some(max_keys_in_list_response)).await;
-
-        match upload_azure_data(&enabled.client, enabled.base_prefix, upload_tasks_count).await {
-            ControlFlow::Continue(uploads) => {
-                info!("Remote objects created successfully");
-
-                Self::Enabled(AzureWithTestBlobs {
-                    enabled,
-                    remote_prefixes: uploads.prefixes,
-                    remote_blobs: uploads.blobs,
-                })
-            }
-            ControlFlow::Break(uploads) => Self::UploadsFailed(
-                anyhow::anyhow!("One or multiple blobs failed to upload to Azure"),
-                AzureWithTestBlobs {
-                    enabled,
-                    remote_prefixes: uploads.prefixes,
-                    remote_blobs: uploads.blobs,
-                },
-            ),
-        }
-    }
-
-    async fn teardown(self) {
-        match self {
-            Self::Disabled => {}
-            Self::Enabled(ctx) | Self::UploadsFailed(_, ctx) => {
-                cleanup(&ctx.enabled.client, ctx.remote_blobs).await;
-            }
-        }
-    }
-}
-
-// NOTE: the setups for the list_prefixes test and the list_files test are very similar
-// However, they are not idential. The list_prefixes function is concerned with listing prefixes,
-// whereas the list_files function is concerned with listing files.
-// See `RemoteStorage::list_files` documentation for more details
-enum MaybeEnabledAzureWithSimpleTestBlobs {
-    Enabled(AzureWithSimpleTestBlobs),
-    Disabled,
-    UploadsFailed(anyhow::Error, AzureWithSimpleTestBlobs),
-}
-struct AzureWithSimpleTestBlobs {
-    enabled: EnabledAzure,
-    remote_blobs: HashSet<RemotePath>,
-}
-
-#[async_trait::async_trait]
-impl AsyncTestContext for MaybeEnabledAzureWithSimpleTestBlobs {
-    async fn setup() -> Self {
-        ensure_logging_ready();
-        if env::var(ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME).is_err() {
-            info!(
-                "`{}` env variable is not set, skipping the test",
-                ENABLE_REAL_AZURE_REMOTE_STORAGE_ENV_VAR_NAME
-            );
-            return Self::Disabled;
-        }
-
-        let max_keys_in_list_response = 10;
-        let upload_tasks_count = 1 + (2 * usize::try_from(max_keys_in_list_response).unwrap());
-
-        let enabled = EnabledAzure::setup(Some(max_keys_in_list_response)).await;
-
-        match upload_simple_azure_data(&enabled.client, upload_tasks_count).await {
-            ControlFlow::Continue(uploads) => {
-                info!("Remote objects created successfully");
-
-                Self::Enabled(AzureWithSimpleTestBlobs {
-                    enabled,
-                    remote_blobs: uploads,
-                })
-            }
-            ControlFlow::Break(uploads) => Self::UploadsFailed(
-                anyhow::anyhow!("One or multiple blobs failed to upload to Azure"),
-                AzureWithSimpleTestBlobs {
-                    enabled,
-                    remote_blobs: uploads,
-                },
-            ),
-        }
-    }
-
-    async fn teardown(self) {
-        match self {
-            Self::Disabled => {}
-            Self::Enabled(ctx) | Self::UploadsFailed(_, ctx) => {
-                cleanup(&ctx.enabled.client, ctx.remote_blobs).await;
-            }
-        }
-    }
-}
-
-fn create_azure_client(
-    max_keys_per_list_response: Option<i32>,
-) -> anyhow::Result<Arc<GenericRemoteStorage>> {
-    use rand::Rng;
-
-    let remote_storage_azure_container = env::var("REMOTE_STORAGE_AZURE_CONTAINER").context(
-        "`REMOTE_STORAGE_AZURE_CONTAINER` env var is not set, but real Azure tests are enabled",
-    )?;
-    let remote_storage_azure_region = env::var("REMOTE_STORAGE_AZURE_REGION").context(
-        "`REMOTE_STORAGE_AZURE_REGION` env var is not set, but real Azure tests are enabled",
-    )?;
-
-    // due to how time works, we've had test runners use the same nanos as bucket prefixes.
-    // millis is just a debugging aid for easier finding the prefix later.
-    let millis = std::time::SystemTime::now()
-        .duration_since(UNIX_EPOCH)
-        .context("random Azure test prefix part calculation")?
-        .as_millis();
-
-    // because nanos can be the same for two threads so can millis, add randomness
-    let random = rand::thread_rng().gen::<u32>();
-
-    let remote_storage_config = RemoteStorageConfig {
-        max_concurrent_syncs: NonZeroUsize::new(100).unwrap(),
-        max_sync_errors: NonZeroU32::new(5).unwrap(),
-        storage: RemoteStorageKind::AzureContainer(AzureConfig {
-            container_name: remote_storage_azure_container,
-            container_region: remote_storage_azure_region,
-            prefix_in_container: Some(format!("test_{millis}_{random:08x}/")),
-            concurrency_limit: NonZeroUsize::new(100).unwrap(),
-            max_keys_per_list_response,
-        }),
-    };
-    Ok(Arc::new(
-        GenericRemoteStorage::from_config(&remote_storage_config).context("remote storage init")?,
-    ))
-}
-
-struct Uploads {
-    prefixes: HashSet<RemotePath>,
-    blobs: HashSet<RemotePath>,
-}
-
-async fn upload_azure_data(
-    client: &Arc<GenericRemoteStorage>,
-    base_prefix_str: &'static str,
-    upload_tasks_count: usize,
-) -> ControlFlow<Uploads, Uploads> {
-    info!("Creating {upload_tasks_count} Azure files");
-    let mut upload_tasks = JoinSet::new();
-    for i in 1..upload_tasks_count + 1 {
-        let task_client = Arc::clone(client);
-        upload_tasks.spawn(async move {
-            let prefix = format!("{base_prefix_str}/sub_prefix_{i}/");
-            let blob_prefix = RemotePath::new(Utf8Path::new(&prefix))
-                .with_context(|| format!("{prefix:?} to RemotePath conversion"))?;
-            let blob_path = blob_prefix.join(Utf8Path::new(&format!("blob_{i}")));
-            debug!("Creating remote item {i} at path {blob_path:?}");
-
-            let data = format!("remote blob data {i}").into_bytes();
-            let data_len = data.len();
-            task_client
-                .upload(std::io::Cursor::new(data), data_len, &blob_path, None)
-                .await?;
-
-            Ok::<_, anyhow::Error>((blob_prefix, blob_path))
-        });
-    }
-
-    let mut upload_tasks_failed = false;
-    let mut uploaded_prefixes = HashSet::with_capacity(upload_tasks_count);
-    let mut uploaded_blobs = HashSet::with_capacity(upload_tasks_count);
-    while let Some(task_run_result) = upload_tasks.join_next().await {
-        match task_run_result
-            .context("task join failed")
-            .and_then(|task_result| task_result.context("upload task failed"))
-        {
-            Ok((upload_prefix, upload_path)) => {
-                uploaded_prefixes.insert(upload_prefix);
-                uploaded_blobs.insert(upload_path);
-            }
-            Err(e) => {
-                error!("Upload task failed: {e:?}");
-                upload_tasks_failed = true;
-            }
-        }
-    }
-
-    let uploads = Uploads {
-        prefixes: uploaded_prefixes,
-        blobs: uploaded_blobs,
-    };
-    if upload_tasks_failed {
-        ControlFlow::Break(uploads)
-    } else {
-        ControlFlow::Continue(uploads)
-    }
-}
-
-async fn cleanup(client: &Arc<GenericRemoteStorage>, objects_to_delete: HashSet<RemotePath>) {
-    info!(
-        "Removing {} objects from the remote storage during cleanup",
-        objects_to_delete.len()
-    );
-    let mut delete_tasks = JoinSet::new();
-    for object_to_delete in objects_to_delete {
-        let task_client = Arc::clone(client);
-        delete_tasks.spawn(async move {
-            debug!("Deleting remote item at path {object_to_delete:?}");
-            task_client
-                .delete(&object_to_delete)
-                .await
-                .with_context(|| format!("{object_to_delete:?} removal"))
-        });
-    }
-
-    while let Some(task_run_result) = delete_tasks.join_next().await {
-        match task_run_result {
-            Ok(task_result) => match task_result {
-                Ok(()) => {}
-                Err(e) => error!("Delete task failed: {e:?}"),
-            },
-            Err(join_err) => error!("Delete task did not finish correctly: {join_err}"),
-        }
-    }
-}
-
-// Uploads files `folder{j}/blob{i}.txt`. See test description for more details.
-async fn upload_simple_azure_data(
-    client: &Arc<GenericRemoteStorage>,
-    upload_tasks_count: usize,
-) -> ControlFlow<HashSet<RemotePath>, HashSet<RemotePath>> {
-    info!("Creating {upload_tasks_count} Azure files");
-    let mut upload_tasks = JoinSet::new();
-    for i in 1..upload_tasks_count + 1 {
-        let task_client = Arc::clone(client);
-        upload_tasks.spawn(async move {
-            let blob_path = PathBuf::from(format!("folder{}/blob_{}.txt", i / 7, i));
-            let blob_path = RemotePath::new(
-                Utf8Path::from_path(blob_path.as_path()).expect("must be valid blob path"),
-            )
-            .with_context(|| format!("{blob_path:?} to RemotePath conversion"))?;
-            debug!("Creating remote item {i} at path {blob_path:?}");
-
-            let data = format!("remote blob data {i}").into_bytes();
-            let data_len = data.len();
-            task_client
-                .upload(std::io::Cursor::new(data), data_len, &blob_path, None)
-                .await?;
-
-            Ok::<_, anyhow::Error>(blob_path)
-        });
-    }
-
-    let mut upload_tasks_failed = false;
-    let mut uploaded_blobs = HashSet::with_capacity(upload_tasks_count);
-    while let Some(task_run_result) = upload_tasks.join_next().await {
-        match task_run_result
-            .context("task join failed")
-            .and_then(|task_result| task_result.context("upload task failed"))
-        {
-            Ok(upload_path) => {
-                uploaded_blobs.insert(upload_path);
-            }
-            Err(e) => {
-                error!("Upload task failed: {e:?}");
-                upload_tasks_failed = true;
-            }
-        }
-    }
-
-    if upload_tasks_failed {
-        ControlFlow::Break(uploaded_blobs)
-    } else {
-        ControlFlow::Continue(uploaded_blobs)
-    }
-}

libs/utils/src/lib.rs

@@ -73,8 +73,6 @@ pub mod completion;
 /// Reporting utilities
 pub mod error;
 
-pub mod sync;
-
 /// This is a shortcut to embed git sha into binaries and avoid copying the same build script to all packages
 ///
 /// we have several cases:
@@ -130,21 +128,6 @@ macro_rules! project_git_version {
     };
 }
 
-/// This is a shortcut to embed build tag into binaries and avoid copying the same build script to all packages
-#[macro_export]
-macro_rules! project_build_tag {
-    ($const_identifier:ident) => {
-        const $const_identifier: &::core::primitive::str = {
-            const __ARG: &[&::core::primitive::str; 2] = &match ::core::option_env!("BUILD_TAG") {
-                ::core::option::Option::Some(x) => ["build_tag-env:", x],
-                ::core::option::Option::None => ["build_tag:", ""],
-            };
-
-            $crate::__const_format::concatcp!(__ARG[0], __ARG[1])
-        };
-    };
-}
-
 /// Re-export for `project_git_version` macro
 #[doc(hidden)]
 pub use const_format as __const_format;

libs/utils/src/sync.rs

@@ -1 +0,0 @@
-pub mod heavier_once_cell;

libs/utils/src/sync/heavier_once_cell.rs

@@ -1,383 +0,0 @@
-use std::sync::{
-    atomic::{AtomicUsize, Ordering},
-    Arc, Mutex, MutexGuard,
-};
-use tokio::sync::Semaphore;
-
-/// Custom design like [`tokio::sync::OnceCell`] but using [`OwnedSemaphorePermit`] instead of
-/// `SemaphorePermit`, allowing use of `take` which does not require holding an outer mutex guard
-/// for the duration of initialization.
-///
-/// Has no unsafe, builds upon [`tokio::sync::Semaphore`] and [`std::sync::Mutex`].
-///
-/// [`OwnedSemaphorePermit`]: tokio::sync::OwnedSemaphorePermit
-pub struct OnceCell<T> {
-    inner: Mutex<Inner<T>>,
-    initializers: AtomicUsize,
-}
-
-impl<T> Default for OnceCell<T> {
-    /// Create new uninitialized [`OnceCell`].
-    fn default() -> Self {
-        Self {
-            inner: Default::default(),
-            initializers: AtomicUsize::new(0),
-        }
-    }
-}
-
-/// Semaphore is the current state:
-/// - open semaphore means the value is `None`, not yet initialized
-/// - closed semaphore means the value has been initialized
-#[derive(Debug)]
-struct Inner<T> {
-    init_semaphore: Arc<Semaphore>,
-    value: Option<T>,
-}
-
-impl<T> Default for Inner<T> {
-    fn default() -> Self {
-        Self {
-            init_semaphore: Arc::new(Semaphore::new(1)),
-            value: None,
-        }
-    }
-}
-
-impl<T> OnceCell<T> {
-    /// Creates an already initialized `OnceCell` with the given value.
-    pub fn new(value: T) -> Self {
-        let sem = Semaphore::new(1);
-        sem.close();
-        Self {
-            inner: Mutex::new(Inner {
-                init_semaphore: Arc::new(sem),
-                value: Some(value),
-            }),
-            initializers: AtomicUsize::new(0),
-        }
-    }
-
-    /// Returns a guard to an existing initialized value, or uniquely initializes the value before
-    /// returning the guard.
-    ///
-    /// Initializing might wait on any existing [`Guard::take_and_deinit`] deinitialization.
-    ///
-    /// Initialization is panic-safe and cancellation-safe.
-    pub async fn get_or_init<F, Fut, E>(&self, factory: F) -> Result<Guard<'_, T>, E>
-    where
-        F: FnOnce(InitPermit) -> Fut,
-        Fut: std::future::Future<Output = Result<(T, InitPermit), E>>,
-    {
-        let sem = {
-            let guard = self.inner.lock().unwrap();
-            if guard.value.is_some() {
-                return Ok(Guard(guard));
-            }
-            guard.init_semaphore.clone()
-        };
-
-        let permit = {
-            // increment the count for the duration of queued
-            let _guard = CountWaitingInitializers::start(self);
-            sem.acquire_owned().await
-        };
-
-        match permit {
-            Ok(permit) => {
-                let permit = InitPermit(permit);
-                let (value, _permit) = factory(permit).await?;
-
-                let guard = self.inner.lock().unwrap();
-
-                Ok(Self::set0(value, guard))
-            }
-            Err(_closed) => {
-                let guard = self.inner.lock().unwrap();
-                assert!(
-                    guard.value.is_some(),
-                    "semaphore got closed, must be initialized"
-                );
-                return Ok(Guard(guard));
-            }
-        }
-    }
-
-    /// Assuming a permit is held after previous call to [`Guard::take_and_deinit`], it can be used
-    /// to complete initializing the inner value.
-    ///
-    /// # Panics
-    ///
-    /// If the inner has already been initialized.
-    pub fn set(&self, value: T, _permit: InitPermit) -> Guard<'_, T> {
-        let guard = self.inner.lock().unwrap();
-
-        // cannot assert that this permit is for self.inner.semaphore, but we can assert it cannot
-        // give more permits right now.
-        if guard.init_semaphore.try_acquire().is_ok() {
-            drop(guard);
-            panic!("permit is of wrong origin");
-        }
-
-        Self::set0(value, guard)
-    }
-
-    fn set0(value: T, mut guard: std::sync::MutexGuard<'_, Inner<T>>) -> Guard<'_, T> {
-        if guard.value.is_some() {
-            drop(guard);
-            unreachable!("we won permit, must not be initialized");
-        }
-        guard.value = Some(value);
-        guard.init_semaphore.close();
-        Guard(guard)
-    }
-
-    /// Returns a guard to an existing initialized value, if any.
-    pub fn get(&self) -> Option<Guard<'_, T>> {
-        let guard = self.inner.lock().unwrap();
-        if guard.value.is_some() {
-            Some(Guard(guard))
-        } else {
-            None
-        }
-    }
-
-    /// Return the number of [`Self::get_or_init`] calls waiting for initialization to complete.
-    pub fn initializer_count(&self) -> usize {
-        self.initializers.load(Ordering::Relaxed)
-    }
-}
-
-/// DropGuard counter for queued tasks waiting to initialize, mainly accessible for the
-/// initializing task for example at the end of initialization.
-struct CountWaitingInitializers<'a, T>(&'a OnceCell<T>);
-
-impl<'a, T> CountWaitingInitializers<'a, T> {
-    fn start(target: &'a OnceCell<T>) -> Self {
-        target.initializers.fetch_add(1, Ordering::Relaxed);
-        CountWaitingInitializers(target)
-    }
-}
-
-impl<'a, T> Drop for CountWaitingInitializers<'a, T> {
-    fn drop(&mut self) {
-        self.0.initializers.fetch_sub(1, Ordering::Relaxed);
-    }
-}
-
-/// Uninteresting guard object to allow short-lived access to inspect or clone the held,
-/// initialized value.
-#[derive(Debug)]
-pub struct Guard<'a, T>(MutexGuard<'a, Inner<T>>);
-
-impl<T> std::ops::Deref for Guard<'_, T> {
-    type Target = T;
-
-    fn deref(&self) -> &Self::Target {
-        self.0
-            .value
-            .as_ref()
-            .expect("guard is not created unless value has been initialized")
-    }
-}
-
-impl<T> std::ops::DerefMut for Guard<'_, T> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        self.0
-            .value
-            .as_mut()
-            .expect("guard is not created unless value has been initialized")
-    }
-}
-
-impl<'a, T> Guard<'a, T> {
-    /// Take the current value, and a new permit for it's deinitialization.
-    ///
-    /// The permit will be on a semaphore part of the new internal value, and any following
-    /// [`OnceCell::get_or_init`] will wait on it to complete.
-    pub fn take_and_deinit(&mut self) -> (T, InitPermit) {
-        let mut swapped = Inner::default();
-        let permit = swapped
-            .init_semaphore
-            .clone()
-            .try_acquire_owned()
-            .expect("we just created this");
-        std::mem::swap(&mut *self.0, &mut swapped);
-        swapped
-            .value
-            .map(|v| (v, InitPermit(permit)))
-            .expect("guard is not created unless value has been initialized")
-    }
-}
-
-/// Type held by OnceCell (de)initializing task.
-pub struct InitPermit(tokio::sync::OwnedSemaphorePermit);
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::{
-        convert::Infallible,
-        sync::atomic::{AtomicUsize, Ordering},
-        time::Duration,
-    };
-
-    #[tokio::test]
-    async fn many_initializers() {
-        #[derive(Default, Debug)]
-        struct Counters {
-            factory_got_to_run: AtomicUsize,
-            future_polled: AtomicUsize,
-            winners: AtomicUsize,
-        }
-
-        let initializers = 100;
-
-        let cell = Arc::new(OnceCell::default());
-        let counters = Arc::new(Counters::default());
-        let barrier = Arc::new(tokio::sync::Barrier::new(initializers + 1));
-
-        let mut js = tokio::task::JoinSet::new();
-        for i in 0..initializers {
-            js.spawn({
-                let cell = cell.clone();
-                let counters = counters.clone();
-                let barrier = barrier.clone();
-
-                async move {
-                    barrier.wait().await;
-                    let won = {
-                        let g = cell
-                            .get_or_init(|permit| {
-                                counters.factory_got_to_run.fetch_add(1, Ordering::Relaxed);
-                                async {
-                                    counters.future_polled.fetch_add(1, Ordering::Relaxed);
-                                    Ok::<_, Infallible>((i, permit))
-                                }
-                            })
-                            .await
-                            .unwrap();
-
-                        *g == i
-                    };
-
-                    if won {
-                        counters.winners.fetch_add(1, Ordering::Relaxed);
-                    }
-                }
-            });
-        }
-
-        barrier.wait().await;
-
-        while let Some(next) = js.join_next().await {
-            next.expect("no panics expected");
-        }
-
-        let mut counters = Arc::try_unwrap(counters).unwrap();
-
-        assert_eq!(*counters.factory_got_to_run.get_mut(), 1);
-        assert_eq!(*counters.future_polled.get_mut(), 1);
-        assert_eq!(*counters.winners.get_mut(), 1);
-    }
-
-    #[tokio::test(start_paused = true)]
-    async fn reinit_waits_for_deinit() {
-        // with the tokio::time paused, we will "sleep" for 1s while holding the reinitialization
-        let sleep_for = Duration::from_secs(1);
-        let initial = 42;
-        let reinit = 1;
-        let cell = Arc::new(OnceCell::new(initial));
-
-        let deinitialization_started = Arc::new(tokio::sync::Barrier::new(2));
-
-        let jh = tokio::spawn({
-            let cell = cell.clone();
-            let deinitialization_started = deinitialization_started.clone();
-            async move {
-                let (answer, _permit) = cell.get().expect("initialized to value").take_and_deinit();
-                assert_eq!(answer, initial);
-
-                deinitialization_started.wait().await;
-                tokio::time::sleep(sleep_for).await;
-            }
-        });
-
-        deinitialization_started.wait().await;
-
-        let started_at = tokio::time::Instant::now();
-        cell.get_or_init(|permit| async { Ok::<_, Infallible>((reinit, permit)) })
-            .await
-            .unwrap();
-
-        let elapsed = started_at.elapsed();
-        assert!(
-            elapsed >= sleep_for,
-            "initialization should had taken at least the time time slept with permit"
-        );
-
-        jh.await.unwrap();
-
-        assert_eq!(*cell.get().unwrap(), reinit);
-    }
-
-    #[test]
-    fn reinit_with_deinit_permit() {
-        let cell = Arc::new(OnceCell::new(42));
-
-        let (mol, permit) = cell.get().unwrap().take_and_deinit();
-        cell.set(5, permit);
-        assert_eq!(*cell.get().unwrap(), 5);
-
-        let (five, permit) = cell.get().unwrap().take_and_deinit();
-        assert_eq!(5, five);
-        cell.set(mol, permit);
-        assert_eq!(*cell.get().unwrap(), 42);
-    }
-
-    #[tokio::test]
-    async fn initialization_attemptable_until_ok() {
-        let cell = OnceCell::default();
-
-        for _ in 0..10 {
-            cell.get_or_init(|_permit| async { Err("whatever error") })
-                .await
-                .unwrap_err();
-        }
-
-        let g = cell
-            .get_or_init(|permit| async { Ok::<_, Infallible>(("finally success", permit)) })
-            .await
-            .unwrap();
-        assert_eq!(*g, "finally success");
-    }
-
-    #[tokio::test]
-    async fn initialization_is_cancellation_safe() {
-        let cell = OnceCell::default();
-
-        let barrier = tokio::sync::Barrier::new(2);
-
-        let initializer = cell.get_or_init(|permit| async {
-            barrier.wait().await;
-            futures::future::pending::<()>().await;
-
-            Ok::<_, Infallible>(("never reached", permit))
-        });
-
-        tokio::select! {
-            _ = initializer => { unreachable!("cannot complete; stuck in pending().await") },
-            _ = barrier.wait() => {}
-        };
-
-        // now initializer is dropped
-
-        assert!(cell.get().is_none());
-
-        let g = cell
-            .get_or_init(|permit| async { Ok::<_, Infallible>(("now initialized", permit)) })
-            .await
-            .unwrap();
-        assert_eq!(*g, "now initialized");
-    }
-}

libs/vm_monitor/README.md

@@ -27,8 +27,8 @@ and old one if it exists.
 * the filecache: a struct that allows communication with the Postgres file cache.
 On startup, we connect to the filecache and hold on to the connection for the
 entire monitor lifetime.
-* the cgroup watcher: the `CgroupWatcher` polls the `neon-postgres` cgroup's memory
-usage and sends rolling aggregates to the runner.
+* the cgroup watcher: the `CgroupWatcher` manages the `neon-postgres` cgroup by
+listening for `memory.high` events and setting its `memory.{high,max}` values.
 * the runner: the runner marries the filecache and cgroup watcher together,
 communicating with the agent throught the `Dispatcher`, and then calling filecache
 and cgroup watcher functions as needed to upscale and downscale

libs/vm_monitor/src/cgroup.rs

@@ -1,38 +1,161 @@
-use std::fmt::{self, Debug, Formatter};
-use std::time::{Duration, Instant};
-
-use anyhow::{anyhow, Context};
-use cgroups_rs::{
-    hierarchies::{self, is_cgroup2_unified_mode},
-    memory::MemController,
-    Subsystem,
+use std::{
+    fmt::{Debug, Display},
+    fs,
+    pin::pin,
+    sync::atomic::{AtomicU64, Ordering},
 };
-use tokio::sync::watch;
+
+use anyhow::{anyhow, bail, Context};
+use cgroups_rs::{
+    freezer::FreezerController,
+    hierarchies::{self, is_cgroup2_unified_mode, UNIFIED_MOUNTPOINT},
+    memory::MemController,
+    MaxValue,
+    Subsystem::{Freezer, Mem},
+};
+use inotify::{EventStream, Inotify, WatchMask};
+use tokio::sync::mpsc::{self, error::TryRecvError};
+use tokio::time::{Duration, Instant};
+use tokio_stream::{Stream, StreamExt};
 use tracing::{info, warn};
 
+use crate::protocol::Resources;
+use crate::MiB;
+
+/// Monotonically increasing counter of the number of memory.high events
+/// the cgroup has experienced.
+///
+/// We use this to determine if a modification to the `memory.events` file actually
+/// changed the `high` field. If not, we don't care about the change. When we
+/// read the file, we check the `high` field in the file against `MEMORY_EVENT_COUNT`
+/// to see if it changed since last time.
+pub static MEMORY_EVENT_COUNT: AtomicU64 = AtomicU64::new(0);
+
+/// Monotonically increasing counter that gives each cgroup event a unique id.
+///
+/// This allows us to answer questions like "did this upscale arrive before this
+/// memory.high?". This static is also used by the `Sequenced` type to "tag" values
+/// with a sequence number. As such, prefer to used the `Sequenced` type rather
+/// than this static directly.
+static EVENT_SEQUENCE_NUMBER: AtomicU64 = AtomicU64::new(0);
+
+/// A memory event type reported in memory.events.
+#[derive(Debug, Eq, PartialEq, Copy, Clone)]
+pub enum MemoryEvent {
+    Low,
+    High,
+    Max,
+    Oom,
+    OomKill,
+    OomGroupKill,
+}
+
+impl MemoryEvent {
+    fn as_str(&self) -> &str {
+        match self {
+            MemoryEvent::Low => "low",
+            MemoryEvent::High => "high",
+            MemoryEvent::Max => "max",
+            MemoryEvent::Oom => "oom",
+            MemoryEvent::OomKill => "oom_kill",
+            MemoryEvent::OomGroupKill => "oom_group_kill",
+        }
+    }
+}
+
+impl Display for MemoryEvent {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(self.as_str())
+    }
+}
+
 /// Configuration for a `CgroupWatcher`
 #[derive(Debug, Clone)]
 pub struct Config {
-    /// Interval at which we should be fetching memory statistics
-    memory_poll_interval: Duration,
+    // The target difference between the total memory reserved for the cgroup
+    // and the value of the cgroup's memory.high.
+    //
+    // In other words, memory.high + oom_buffer_bytes will equal the total memory that the cgroup may
+    // use (equal to system memory, minus whatever's taken out for the file cache).
+    oom_buffer_bytes: u64,
 
-    /// The number of samples used in constructing aggregated memory statistics
-    memory_history_len: usize,
-    /// The number of most recent samples that will be periodically logged.
-    ///
-    /// Each sample is logged exactly once. Increasing this value means that recent samples will be
-    /// logged less frequently, and vice versa.
-    ///
-    /// For simplicity, this value must be greater than or equal to `memory_history_len`.
-    memory_history_log_interval: usize,
+    // The amount of memory, in bytes, below a proposed new value for
+    // memory.high that the cgroup's memory usage must be for us to downscale
+    //
+    // In other words, we can downscale only when:
+    //
+    //   memory.current + memory_high_buffer_bytes < (proposed) memory.high
+    //
+    // TODO: there's some minor issues with this approach -- in particular, that we might have
+    // memory in use by the kernel's page cache that we're actually ok with getting rid of.
+    pub(crate) memory_high_buffer_bytes: u64,
+
+    // The maximum duration, in milliseconds, that we're allowed to pause
+    // the cgroup for while waiting for the autoscaler-agent to upscale us
+    max_upscale_wait: Duration,
+
+    // The required minimum time, in milliseconds, that we must wait before re-freezing
+    // the cgroup while waiting for the autoscaler-agent to upscale us.
+    do_not_freeze_more_often_than: Duration,
+
+    // The amount of memory, in bytes, that we should periodically increase memory.high
+    // by while waiting for the autoscaler-agent to upscale us.
+    //
+    // This exists to avoid the excessive throttling that happens when a cgroup is above its
+    // memory.high for too long. See more here:
+    // https://github.com/neondatabase/autoscaling/issues/44#issuecomment-1522487217
+    memory_high_increase_by_bytes: u64,
+
+    // The period, in milliseconds, at which we should repeatedly increase the value
+    // of the cgroup's memory.high while we're waiting on upscaling and memory.high
+    // is still being hit.
+    //
+    // Technically speaking, this actually serves as a rate limit to moderate responding to
+    // memory.high events, but these are roughly equivalent if the process is still allocating
+    // memory.
+    memory_high_increase_every: Duration,
+}
+
+impl Config {
+    /// Calculate the new value for the cgroups memory.high based on system memory
+    pub fn calculate_memory_high_value(&self, total_system_mem: u64) -> u64 {
+        total_system_mem.saturating_sub(self.oom_buffer_bytes)
+    }
 }
 
 impl Default for Config {
     fn default() -> Self {
         Self {
-            memory_poll_interval: Duration::from_millis(100),
-            memory_history_len: 5, // use 500ms of history for decision-making
-            memory_history_log_interval: 20, // but only log every ~2s (otherwise it's spammy)
+            oom_buffer_bytes: 100 * MiB,
+            memory_high_buffer_bytes: 100 * MiB,
+            // while waiting for upscale, don't freeze for more than 20ms every 1s
+            max_upscale_wait: Duration::from_millis(20),
+            do_not_freeze_more_often_than: Duration::from_millis(1000),
+            // while waiting for upscale, increase memory.high by 10MiB every 25ms
+            memory_high_increase_by_bytes: 10 * MiB,
+            memory_high_increase_every: Duration::from_millis(25),
+        }
+    }
+}
+
+/// Used to represent data that is associated with a certain point in time, such
+/// as an upscale request or memory.high event.
+///
+/// Internally, creating a `Sequenced` uses a static atomic counter to obtain
+/// a unique sequence number. Sequence numbers are monotonically increasing,
+/// allowing us to answer questions like "did this upscale happen after this
+/// memory.high event?" by comparing the sequence numbers of the two events.
+#[derive(Debug, Clone)]
+pub struct Sequenced<T> {
+    seqnum: u64,
+    data: T,
+}
+
+impl<T> Sequenced<T> {
+    pub fn new(data: T) -> Self {
+        Self {
+            seqnum: EVENT_SEQUENCE_NUMBER.fetch_add(1, Ordering::AcqRel),
+            data,
         }
     }
 }
@@ -47,14 +170,74 @@ impl Default for Config {
 pub struct CgroupWatcher {
     pub config: Config,
 
+    /// The sequence number of the last upscale.
+    ///
+    /// If we receive a memory.high event that has a _lower_ sequence number than
+    /// `last_upscale_seqnum`, then we know it occured before the upscale, and we
+    /// can safely ignore it.
+    ///
+    /// Note: Like the `events` field, this doesn't _need_ interior mutability but we
+    /// use it anyways so that methods take `&self`, not `&mut self`.
+    last_upscale_seqnum: AtomicU64,
+
+    /// A channel on which we send messages to request upscale from the dispatcher.
+    upscale_requester: mpsc::Sender<()>,
+
     /// The actual cgroup we are watching and managing.
     cgroup: cgroups_rs::Cgroup,
 }
 
+/// Read memory.events for the desired event type.
+///
+/// `path` specifies the path to the desired `memory.events` file.
+/// For more info, see the `memory.events` section of the [kernel docs]
+/// <https://docs.kernel.org/admin-guide/cgroup-v2.html#memory-interface-files>
+fn get_event_count(path: &str, event: MemoryEvent) -> anyhow::Result<u64> {
+    let contents = fs::read_to_string(path)
+        .with_context(|| format!("failed to read memory.events from {path}"))?;
+
+    // Then contents of the file look like:
+    // low 42
+    // high 101
+    // ...
+    contents
+        .lines()
+        .filter_map(|s| s.split_once(' '))
+        .find(|(e, _)| *e == event.as_str())
+        .ok_or_else(|| anyhow!("failed to find entry for memory.{event} events in {path}"))
+        .and_then(|(_, count)| {
+            count
+                .parse::<u64>()
+                .with_context(|| format!("failed to parse memory.{event} as u64"))
+        })
+}
+
+/// Create an event stream that produces events whenever the file at the provided
+/// path is modified.
+fn create_file_watcher(path: &str) -> anyhow::Result<EventStream<[u8; 1024]>> {
+    info!("creating file watcher for {path}");
+    let inotify = Inotify::init().context("failed to initialize file watcher")?;
+    inotify
+        .watches()
+        .add(path, WatchMask::MODIFY)
+        .with_context(|| format!("failed to start watching {path}"))?;
+    inotify
+        // The inotify docs use [0u8; 1024] so we'll just copy them. We only need
+        // to store one event at a time - if the event gets written over, that's
+        // ok. We still see that there is an event. For more information, see:
+        // https://man7.org/linux/man-pages/man7/inotify.7.html
+        .into_event_stream([0u8; 1024])
+        .context("failed to start inotify event stream")
+}
+
 impl CgroupWatcher {
     /// Create a new `CgroupWatcher`.
     #[tracing::instrument(skip_all, fields(%name))]
-    pub fn new(name: String) -> anyhow::Result<Self> {
+    pub fn new(
+        name: String,
+        // A channel on which to send upscale requests
+        upscale_requester: mpsc::Sender<()>,
+    ) -> anyhow::Result<(Self, impl Stream<Item = Sequenced<u64>>)> {
         // TODO: clarify exactly why we need v2
         // Make sure cgroups v2 (aka unified) are supported
         if !is_cgroup2_unified_mode() {
@@ -62,203 +245,410 @@ impl CgroupWatcher {
         }
         let cgroup = cgroups_rs::Cgroup::load(hierarchies::auto(), &name);
 
-        Ok(Self {
-            cgroup,
-            config: Default::default(),
-        })
+        // Start monitoring the cgroup for memory events. In general, for
+        // cgroups v2 (aka unified), metrics are reported in files like
+        // > `/sys/fs/cgroup/{name}/{metric}`
+        // We are looking for `memory.high` events, which are stored in the
+        // file `memory.events`. For more info, see the `memory.events` section
+        // of https://docs.kernel.org/admin-guide/cgroup-v2.html#memory-interface-files
+        let path = format!("{}/{}/memory.events", UNIFIED_MOUNTPOINT, &name);
+        let memory_events = create_file_watcher(&path)
+            .with_context(|| format!("failed to create event watcher for {path}"))?
+            // This would be nice with with .inspect_err followed by .ok
+            .filter_map(move |_| match get_event_count(&path, MemoryEvent::High) {
+                Ok(high) => Some(high),
+                Err(error) => {
+                    // TODO: Might want to just panic here
+                    warn!(?error, "failed to read high events count from {}", &path);
+                    None
+                }
+            })
+            // Only report the event if the memory.high count increased
+            .filter_map(|high| {
+                if MEMORY_EVENT_COUNT.fetch_max(high, Ordering::AcqRel) < high {
+                    Some(high)
+                } else {
+                    None
+                }
+            })
+            .map(Sequenced::new);
+
+        let initial_count = get_event_count(
+            &format!("{}/{}/memory.events", UNIFIED_MOUNTPOINT, &name),
+            MemoryEvent::High,
+        )?;
+
+        info!(initial_count, "initial memory.high event count");
+
+        // Hard update `MEMORY_EVENT_COUNT` since there could have been processes
+        // running in the cgroup before that caused it to be non-zero.
+        MEMORY_EVENT_COUNT.fetch_max(initial_count, Ordering::AcqRel);
+
+        Ok((
+            Self {
+                cgroup,
+                upscale_requester,
+                last_upscale_seqnum: AtomicU64::new(0),
+                config: Default::default(),
+            },
+            memory_events,
+        ))
     }
 
     /// The entrypoint for the `CgroupWatcher`.
     #[tracing::instrument(skip_all)]
-    pub async fn watch(
+    pub async fn watch<E>(
         &self,
-        updates: watch::Sender<(Instant, MemoryHistory)>,
-    ) -> anyhow::Result<()> {
-        // this requirement makes the code a bit easier to work with; see the config for more.
-        assert!(self.config.memory_history_len <= self.config.memory_history_log_interval);
+        // These are ~dependency injected~ (fancy, I know) because this function
+        // should never return.
+        // -> therefore: when we tokio::spawn it, we don't await the JoinHandle.
+        // -> therefore: if we want to stick it in an Arc so many threads can access
+        //    it, methods can never take mutable access.
+        //     - note: we use the Arc strategy so that a) we can call this function
+        //             right here and b) the runner can call the set/get_memory methods
+        // -> since calling recv() on a tokio::sync::mpsc::Receiver takes &mut self,
+        //    we just pass them in here instead of holding them in fields, as that
+        //    would require this method to take &mut self.
+        mut upscales: mpsc::Receiver<Sequenced<Resources>>,
+        events: E,
+    ) -> anyhow::Result<()>
+    where
+        E: Stream<Item = Sequenced<u64>>,
+    {
+        let mut wait_to_freeze = pin!(tokio::time::sleep(Duration::ZERO));
+        let mut last_memory_high_increase_at: Option<Instant> = None;
+        let mut events = pin!(events);
 
-        let mut ticker = tokio::time::interval(self.config.memory_poll_interval);
-        ticker.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);
-        // ticker.reset_immediately(); // FIXME: enable this once updating to tokio >= 1.30.0
+        // Are we waiting to be upscaled? Could be true if we request upscale due
+        // to a memory.high event and it does not arrive in time.
+        let mut waiting_on_upscale = false;
 
-        let mem_controller = self.memory()?;
+        loop {
+            tokio::select! {
+                upscale = upscales.recv() => {
+                    let Sequenced { seqnum, data } = upscale
+                        .context("failed to listen on upscale notification channel")?;
+                    waiting_on_upscale = false;
+                    last_memory_high_increase_at = None;
+                    self.last_upscale_seqnum.store(seqnum, Ordering::Release);
+                    info!(cpu = data.cpu, mem_bytes = data.mem, "received upscale");
+                }
+                event = events.next() => {
+                    let Some(Sequenced { seqnum, .. }) = event else {
+                        bail!("failed to listen for memory.high events")
+                    };
+                    // The memory.high came before our last upscale, so we consider
+                    // it resolved
+                    if self.last_upscale_seqnum.fetch_max(seqnum, Ordering::AcqRel) > seqnum {
+                        info!(
+                            "received memory.high event, but it came before our last upscale -> ignoring it"
+                        );
+                        continue;
+                    }
 
-        // buffer for samples that will be logged. once full, it remains so.
-        let history_log_len = self.config.memory_history_log_interval;
-        let mut history_log_buf = vec![MemoryStatus::zeroed(); history_log_len];
+                    // The memory.high came after our latest upscale. We don't
+                    // want to do anything yet, so peek the next event in hopes
+                    // that it's an upscale.
+                    if let Some(upscale_num) = self
+                        .upscaled(&mut upscales)
+                        .context("failed to check if we were upscaled")?
+                    {
+                        if upscale_num > seqnum {
+                            info!(
+                                "received memory.high event, but it came before our last upscale -> ignoring it"
+                            );
+                            continue;
+                        }
+                    }
 
-        for t in 0_u64.. {
-            ticker.tick().await;
+                    // If it's been long enough since we last froze, freeze the
+                    // cgroup and request upscale
+                    if wait_to_freeze.is_elapsed() {
+                        info!("received memory.high event -> requesting upscale");
+                        waiting_on_upscale = self
+                            .handle_memory_high_event(&mut upscales)
+                            .await
+                            .context("failed to handle upscale")?;
+                        wait_to_freeze
+                            .as_mut()
+                            .reset(Instant::now() + self.config.do_not_freeze_more_often_than);
+                        continue;
+                    }
 
-            let now = Instant::now();
-            let mem = Self::memory_usage(mem_controller);
+                    // Ok, we can't freeze, just request upscale
+                    if !waiting_on_upscale {
+                        info!("received memory.high event, but too soon to refreeze -> requesting upscale");
 
-            let i = t as usize % history_log_len;
-            history_log_buf[i] = mem;
+                        // Make check to make sure we haven't been upscaled in the
+                        // meantine (can happen if the agent independently decides
+                        // to upscale us again)
+                        if self
+                            .upscaled(&mut upscales)
+                            .context("failed to check if we were upscaled")?
+                            .is_some()
+                        {
+                            info!("no need to request upscaling because we got upscaled");
+                            continue;
+                        }
+                        self.upscale_requester
+                            .send(())
+                            .await
+                            .context("failed to request upscale")?;
+                        waiting_on_upscale = true;
+                        continue;
+                    }
 
-            // We're taking *at most* memory_history_len values; we may be bounded by the total
-            // number of samples that have come in so far.
-            let samples_count = (t + 1).min(self.config.memory_history_len as u64) as usize;
-            // NB: in `ring_buf_recent_values_iter`, `i` is *inclusive*, which matches the fact
-            // that we just inserted a value there, so the end of the iterator will *include* the
-            // value at i, rather than stopping just short of it.
-            let samples = ring_buf_recent_values_iter(&history_log_buf, i, samples_count);
+                    // Shoot, we can't freeze or and we're still waiting on upscale,
+                    // increase memory.high to reduce throttling
+                    let can_increase_memory_high = match last_memory_high_increase_at {
+                        None => true,
+                        Some(t) => t.elapsed() > self.config.memory_high_increase_every,
+                    };
+                    if can_increase_memory_high {
+                        info!(
+                            "received memory.high event, \
+                            but too soon to refreeze and already requested upscale \
+                            -> increasing memory.high"
+                        );
 
-            let summary = MemoryHistory {
-                avg_non_reclaimable: samples.map(|h| h.non_reclaimable).sum::<u64>()
-                    / samples_count as u64,
-                samples_count,
-                samples_span: self.config.memory_poll_interval * (samples_count - 1) as u32,
+                        // Make check to make sure we haven't been upscaled in the
+                        // meantine (can happen if the agent independently decides
+                        // to upscale us again)
+                        if self
+                            .upscaled(&mut upscales)
+                            .context("failed to check if we were upscaled")?
+                            .is_some()
+                        {
+                            info!("no need to increase memory.high because got upscaled");
+                            continue;
+                        }
+
+                        // Request upscale anyways (the agent will handle deduplicating
+                        // requests)
+                        self.upscale_requester
+                            .send(())
+                            .await
+                            .context("failed to request upscale")?;
+
+                        let memory_high =
+                            self.get_memory_high_bytes().context("failed to get memory.high")?;
+                        let new_high = memory_high + self.config.memory_high_increase_by_bytes;
+                        info!(
+                            current_high_bytes = memory_high,
+                            new_high_bytes = new_high,
+                            "updating memory.high"
+                        );
+                        self.set_memory_high_bytes(new_high)
+                            .context("failed to set memory.high")?;
+                        last_memory_high_increase_at = Some(Instant::now());
+                        continue;
+                    }
+
+                    info!("received memory.high event, but can't do anything");
+                }
             };
-
-            // Log the current history if it's time to do so. Because `history_log_buf` has length
-            // equal to the logging interval, we can just log the entire buffer every time we set
-            // the last entry, which also means that for this log line, we can ignore that it's a
-            // ring buffer (because all the entries are in order of increasing time).
-            if i == history_log_len - 1 {
-                info!(
-                    history = ?MemoryStatus::debug_slice(&history_log_buf),
-                    summary = ?summary,
-                    "Recent cgroup memory statistics history"
-                );
-            }
-
-            updates
-                .send((now, summary))
-                .context("failed to send MemoryHistory")?;
         }
+    }
 
-        unreachable!()
+    /// Handle a `memory.high`, returning whether we are still waiting on upscale
+    /// by the time the function returns.
+    ///
+    /// The general plan for handling a `memory.high` event is as follows:
+    /// 1. Freeze the cgroup
+    /// 2. Start a timer for `self.config.max_upscale_wait`
+    /// 3. Request upscale
+    /// 4. After the timer elapses or we receive upscale, thaw the cgroup.
+    /// 5. Return whether or not we are still waiting for upscale. If we are,
+    ///    we'll increase the cgroups memory.high to avoid getting oom killed
+    #[tracing::instrument(skip_all)]
+    async fn handle_memory_high_event(
+        &self,
+        upscales: &mut mpsc::Receiver<Sequenced<Resources>>,
+    ) -> anyhow::Result<bool> {
+        // Immediately freeze the cgroup before doing anything else.
+        info!("received memory.high event -> freezing cgroup");
+        self.freeze().context("failed to freeze cgroup")?;
+
+        // We'll use this for logging durations
+        let start_time = Instant::now();
+
+        // Await the upscale until we have to unfreeze
+        let timed =
+            tokio::time::timeout(self.config.max_upscale_wait, self.await_upscale(upscales));
+
+        // Request the upscale
+        info!(
+            wait = ?self.config.max_upscale_wait,
+            "sending request for immediate upscaling",
+        );
+        self.upscale_requester
+            .send(())
+            .await
+            .context("failed to request upscale")?;
+
+        let waiting_on_upscale = match timed.await {
+            Ok(Ok(())) => {
+                info!(elapsed = ?start_time.elapsed(), "received upscale in time");
+                false
+            }
+            // **important**: unfreeze the cgroup before ?-reporting the error
+            Ok(Err(e)) => {
+                info!("error waiting for upscale -> thawing cgroup");
+                self.thaw()
+                    .context("failed to thaw cgroup after errored waiting for upscale")?;
+                Err(e.context("failed to await upscale"))?
+            }
+            Err(_) => {
+                info!(elapsed = ?self.config.max_upscale_wait, "timed out waiting for upscale");
+                true
+            }
+        };
+
+        info!("thawing cgroup");
+        self.thaw().context("failed to thaw cgroup")?;
+
+        Ok(waiting_on_upscale)
+    }
+
+    /// Checks whether we were just upscaled, returning the upscale's sequence
+    /// number if so.
+    #[tracing::instrument(skip_all)]
+    fn upscaled(
+        &self,
+        upscales: &mut mpsc::Receiver<Sequenced<Resources>>,
+    ) -> anyhow::Result<Option<u64>> {
+        let Sequenced { seqnum, data } = match upscales.try_recv() {
+            Ok(upscale) => upscale,
+            Err(TryRecvError::Empty) => return Ok(None),
+            Err(TryRecvError::Disconnected) => {
+                bail!("upscale notification channel was disconnected")
+            }
+        };
+
+        // Make sure to update the last upscale sequence number
+        self.last_upscale_seqnum.store(seqnum, Ordering::Release);
+        info!(cpu = data.cpu, mem_bytes = data.mem, "received upscale");
+        Ok(Some(seqnum))
+    }
+
+    /// Await an upscale event, discarding any `memory.high` events received in
+    /// the process.
+    ///
+    /// This is used in `handle_memory_high_event`, where we need to listen
+    /// for upscales in particular so we know if we can thaw the cgroup early.
+    #[tracing::instrument(skip_all)]
+    async fn await_upscale(
+        &self,
+        upscales: &mut mpsc::Receiver<Sequenced<Resources>>,
+    ) -> anyhow::Result<()> {
+        let Sequenced { seqnum, .. } = upscales
+            .recv()
+            .await
+            .context("error listening for upscales")?;
+
+        self.last_upscale_seqnum.store(seqnum, Ordering::Release);
+        Ok(())
+    }
+
+    /// Get the cgroup's name.
+    pub fn path(&self) -> &str {
+        self.cgroup.path()
+    }
+}
+
+// Methods for manipulating the actual cgroup
+impl CgroupWatcher {
+    /// Get a handle on the freezer subsystem.
+    fn freezer(&self) -> anyhow::Result<&FreezerController> {
+        if let Some(Freezer(freezer)) = self
+            .cgroup
+            .subsystems()
+            .iter()
+            .find(|sub| matches!(sub, Freezer(_)))
+        {
+            Ok(freezer)
+        } else {
+            anyhow::bail!("could not find freezer subsystem")
+        }
+    }
+
+    /// Attempt to freeze the cgroup.
+    pub fn freeze(&self) -> anyhow::Result<()> {
+        self.freezer()
+            .context("failed to get freezer subsystem")?
+            .freeze()
+            .context("failed to freeze")
+    }
+
+    /// Attempt to thaw the cgroup.
+    pub fn thaw(&self) -> anyhow::Result<()> {
+        self.freezer()
+            .context("failed to get freezer subsystem")?
+            .thaw()
+            .context("failed to thaw")
     }
 
     /// Get a handle on the memory subsystem.
+    ///
+    /// Note: this method does not require `self.memory_update_lock` because
+    /// getting a handle to the subsystem does not access any of the files we
+    /// care about, such as memory.high and memory.events
     fn memory(&self) -> anyhow::Result<&MemController> {
-        self.cgroup
+        if let Some(Mem(memory)) = self
+            .cgroup
             .subsystems()
             .iter()
-            .find_map(|sub| match sub {
-                Subsystem::Mem(c) => Some(c),
-                _ => None,
+            .find(|sub| matches!(sub, Mem(_)))
+        {
+            Ok(memory)
+        } else {
+            anyhow::bail!("could not find memory subsystem")
+        }
+    }
+
+    /// Get cgroup current memory usage.
+    pub fn current_memory_usage(&self) -> anyhow::Result<u64> {
+        Ok(self
+            .memory()
+            .context("failed to get memory subsystem")?
+            .memory_stat()
+            .usage_in_bytes)
+    }
+
+    /// Set cgroup memory.high threshold.
+    pub fn set_memory_high_bytes(&self, bytes: u64) -> anyhow::Result<()> {
+        self.set_memory_high_internal(MaxValue::Value(u64::min(bytes, i64::MAX as u64) as i64))
+    }
+
+    /// Set the cgroup's memory.high to 'max', disabling it.
+    pub fn unset_memory_high(&self) -> anyhow::Result<()> {
+        self.set_memory_high_internal(MaxValue::Max)
+    }
+
+    fn set_memory_high_internal(&self, value: MaxValue) -> anyhow::Result<()> {
+        self.memory()
+            .context("failed to get memory subsystem")?
+            .set_mem(cgroups_rs::memory::SetMemory {
+                low: None,
+                high: Some(value),
+                min: None,
+                max: None,
             })
-            .ok_or_else(|| anyhow!("could not find memory subsystem"))
+            .map_err(anyhow::Error::from)
     }
 
-    /// Given a handle on the memory subsystem, returns the current memory information
-    fn memory_usage(mem_controller: &MemController) -> MemoryStatus {
-        let stat = mem_controller.memory_stat().stat;
-        MemoryStatus {
-            non_reclaimable: stat.active_anon + stat.inactive_anon,
+    /// Get memory.high threshold.
+    pub fn get_memory_high_bytes(&self) -> anyhow::Result<u64> {
+        let high = self
+            .memory()
+            .context("failed to get memory subsystem while getting memory statistics")?
+            .get_mem()
+            .map(|mem| mem.high)
+            .context("failed to get memory statistics from subsystem")?;
+        match high {
+            Some(MaxValue::Max) => Ok(i64::MAX as u64),
+            Some(MaxValue::Value(high)) => Ok(high as u64),
+            None => anyhow::bail!("failed to read memory.high from memory subsystem"),
         }
     }
 }
-
-// Helper function for `CgroupWatcher::watch`
-fn ring_buf_recent_values_iter<T>(
-    buf: &[T],
-    last_value_idx: usize,
-    count: usize,
-) -> impl '_ + Iterator<Item = &T> {
-    // Assertion carried over from `CgroupWatcher::watch`, to make the logic in this function
-    // easier (we only have to add `buf.len()` once, rather than a dynamic number of times).
-    assert!(count <= buf.len());
-
-    buf.iter()
-        // 'cycle' because the values could wrap around
-        .cycle()
-        // with 'cycle', this skip is more like 'offset', and functionally this is
-        // offsettting by 'last_value_idx - count (mod buf.len())', but we have to be
-        // careful to avoid underflow, so we pre-add buf.len().
-        // The '+ 1' is because `last_value_idx` is inclusive, rather than exclusive.
-        .skip((buf.len() + last_value_idx + 1 - count) % buf.len())
-        .take(count)
-}
-
-/// Summary of recent memory usage
-#[derive(Debug, Copy, Clone)]
-pub struct MemoryHistory {
-    /// Rolling average of non-reclaimable memory usage samples over the last `history_period`
-    pub avg_non_reclaimable: u64,
-
-    /// The number of samples used to construct this summary
-    pub samples_count: usize,
-    /// Total timespan between the first and last sample used for this summary
-    pub samples_span: Duration,
-}
-
-#[derive(Debug, Copy, Clone)]
-pub struct MemoryStatus {
-    non_reclaimable: u64,
-}
-
-impl MemoryStatus {
-    fn zeroed() -> Self {
-        MemoryStatus { non_reclaimable: 0 }
-    }
-
-    fn debug_slice(slice: &[Self]) -> impl '_ + Debug {
-        struct DS<'a>(&'a [MemoryStatus]);
-
-        impl<'a> Debug for DS<'a> {
-            fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-                f.debug_struct("[MemoryStatus]")
-                    .field(
-                        "non_reclaimable[..]",
-                        &Fields(self.0, |stat: &MemoryStatus| {
-                            BytesToGB(stat.non_reclaimable)
-                        }),
-                    )
-                    .finish()
-            }
-        }
-
-        struct Fields<'a, F>(&'a [MemoryStatus], F);
-
-        impl<'a, F: Fn(&MemoryStatus) -> T, T: Debug> Debug for Fields<'a, F> {
-            fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-                f.debug_list().entries(self.0.iter().map(&self.1)).finish()
-            }
-        }
-
-        struct BytesToGB(u64);
-
-        impl Debug for BytesToGB {
-            fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-                f.write_fmt(format_args!(
-                    "{:.3}Gi",
-                    self.0 as f64 / (1_u64 << 30) as f64
-                ))
-            }
-        }
-
-        DS(slice)
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn ring_buf_iter() {
-        let buf = vec![0_i32, 1, 2, 3, 4, 5, 6, 7, 8, 9];
-
-        let values = |offset, count| {
-            super::ring_buf_recent_values_iter(&buf, offset, count)
-                .copied()
-                .collect::<Vec<i32>>()
-        };
-
-        // Boundary conditions: start, end, and entire thing:
-        assert_eq!(values(0, 1), [0]);
-        assert_eq!(values(3, 4), [0, 1, 2, 3]);
-        assert_eq!(values(9, 4), [6, 7, 8, 9]);
-        assert_eq!(values(9, 10), [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
-
-        // "normal" operation: no wraparound
-        assert_eq!(values(7, 4), [4, 5, 6, 7]);
-
-        // wraparound:
-        assert_eq!(values(0, 4), [7, 8, 9, 0]);
-        assert_eq!(values(1, 4), [8, 9, 0, 1]);
-        assert_eq!(values(2, 4), [9, 0, 1, 2]);
-        assert_eq!(values(2, 10), [3, 4, 5, 6, 7, 8, 9, 0, 1, 2]);
-    }
-}

libs/vm_monitor/src/dispatcher.rs

@@ -12,10 +12,12 @@ use futures::{
     stream::{SplitSink, SplitStream},
     SinkExt, StreamExt,
 };
+use tokio::sync::mpsc;
 use tracing::info;
 
+use crate::cgroup::Sequenced;
 use crate::protocol::{
-    OutboundMsg, ProtocolRange, ProtocolResponse, ProtocolVersion, PROTOCOL_MAX_VERSION,
+    OutboundMsg, ProtocolRange, ProtocolResponse, ProtocolVersion, Resources, PROTOCOL_MAX_VERSION,
     PROTOCOL_MIN_VERSION,
 };
 
@@ -34,6 +36,13 @@ pub struct Dispatcher {
     /// We send messages to the agent through `sink`
     sink: SplitSink<WebSocket, Message>,
 
+    /// Used to notify the cgroup when we are upscaled.
+    pub(crate) notify_upscale_events: mpsc::Sender<Sequenced<Resources>>,
+
+    /// When the cgroup requests upscale it will send on this channel. In response
+    /// we send an `UpscaleRequst` to the agent.
+    pub(crate) request_upscale_events: mpsc::Receiver<()>,
+
     /// The protocol version we have agreed to use with the agent. This is negotiated
     /// during the creation of the dispatcher, and should be the highest shared protocol
     /// version.
@@ -52,7 +61,11 @@ impl Dispatcher {
     /// 1. Wait for the agent to sent the range of protocols it supports.
     /// 2. Send a protocol version that works for us as well, or an error if there
     ///    is no compatible version.
-    pub async fn new(stream: WebSocket) -> anyhow::Result<Self> {
+    pub async fn new(
+        stream: WebSocket,
+        notify_upscale_events: mpsc::Sender<Sequenced<Resources>>,
+        request_upscale_events: mpsc::Receiver<()>,
+    ) -> anyhow::Result<Self> {
         let (mut sink, mut source) = stream.split();
 
         // Figure out the highest protocol version we both support
@@ -106,10 +119,22 @@ impl Dispatcher {
         Ok(Self {
             sink,
             source,
+            notify_upscale_events,
+            request_upscale_events,
             proto_version: highest_shared_version,
         })
     }
 
+    /// Notify the cgroup manager that we have received upscale and wait for
+    /// the acknowledgement.
+    #[tracing::instrument(skip_all, fields(?resources))]
+    pub async fn notify_upscale(&self, resources: Sequenced<Resources>) -> anyhow::Result<()> {
+        self.notify_upscale_events
+            .send(resources)
+            .await
+            .context("failed to send resources and oneshot sender across channel")
+    }
+
     /// Send a message to the agent.
     ///
     /// Although this function is small, it has one major benefit: it is the only

libs/vm_monitor/src/filecache.rs

@@ -21,6 +21,11 @@ pub struct FileCacheState {
 
 #[derive(Debug)]
 pub struct FileCacheConfig {
+    /// Whether the file cache is *actually* stored in memory (e.g. by writing to
+    /// a tmpfs or shmem file). If true, the size of the file cache will be counted against the
+    /// memory available for the cgroup.
+    pub(crate) in_memory: bool,
+
     /// The size of the file cache, in terms of the size of the resource it consumes
     /// (currently: only memory)
     ///
@@ -54,9 +59,22 @@ pub struct FileCacheConfig {
     spread_factor: f64,
 }
 
-impl Default for FileCacheConfig {
-    fn default() -> Self {
+impl FileCacheConfig {
+    pub fn default_in_memory() -> Self {
         Self {
+            in_memory: true,
+            // 75 %
+            resource_multiplier: 0.75,
+            // 640 MiB; (512 + 128)
+            min_remaining_after_cache: NonZeroU64::new(640 * MiB).unwrap(),
+            // ensure any increase in file cache size is split 90-10 with 10% to other memory
+            spread_factor: 0.1,
+        }
+    }
+
+    pub fn default_on_disk() -> Self {
+        Self {
+            in_memory: false,
             resource_multiplier: 0.75,
             // 256 MiB - lower than when in memory because overcommitting is safe; if we don't have
             // memory, the kernel will just evict from its page cache, rather than e.g. killing
@@ -65,9 +83,7 @@ impl Default for FileCacheConfig {
             spread_factor: 0.1,
         }
     }
-}
 
-impl FileCacheConfig {
     /// Make sure fields of the config are consistent.
     pub fn validate(&self) -> anyhow::Result<()> {
         // Single field validity

libs/vm_monitor/src/lib.rs

@@ -39,6 +39,16 @@ pub struct Args {
     #[arg(short, long)]
     pub pgconnstr: Option<String>,
 
+    /// Flag to signal that the Postgres file cache is on disk (i.e. not in memory aside from the
+    /// kernel's page cache), and therefore should not count against available memory.
+    //
+    // NB: Ideally this flag would directly refer to whether the file cache is in memory (rather
+    // than a roundabout way, via whether it's on disk), but in order to be backwards compatible
+    // during the switch away from an in-memory file cache, we had to default to the previous
+    // behavior.
+    #[arg(long)]
+    pub file_cache_on_disk: bool,
+
     /// The address we should listen on for connection requests. For the
     /// agent, this is 0.0.0.0:10301. For the informant, this is 127.0.0.1:10369.
     #[arg(short, long)]

libs/vm_monitor/src/runner.rs

@@ -5,16 +5,18 @@
 //! all functionality.
 
 use std::fmt::Debug;
+use std::sync::Arc;
 use std::time::{Duration, Instant};
 
 use anyhow::{bail, Context};
 use axum::extract::ws::{Message, WebSocket};
 use futures::StreamExt;
-use tokio::sync::{broadcast, watch};
+use tokio::sync::broadcast;
+use tokio::sync::mpsc;
 use tokio_util::sync::CancellationToken;
 use tracing::{error, info, warn};
 
-use crate::cgroup::{self, CgroupWatcher};
+use crate::cgroup::{CgroupWatcher, Sequenced};
 use crate::dispatcher::Dispatcher;
 use crate::filecache::{FileCacheConfig, FileCacheState};
 use crate::protocol::{InboundMsg, InboundMsgKind, OutboundMsg, OutboundMsgKind, Resources};
@@ -26,7 +28,7 @@ use crate::{bytes_to_mebibytes, get_total_system_memory, spawn_with_cancel, Args
 pub struct Runner {
     config: Config,
     filecache: Option<FileCacheState>,
-    cgroup: Option<CgroupState>,
+    cgroup: Option<Arc<CgroupWatcher>>,
     dispatcher: Dispatcher,
 
     /// We "mint" new message ids by incrementing this counter and taking the value.
@@ -43,14 +45,6 @@ pub struct Runner {
     kill: broadcast::Receiver<()>,
 }
 
-#[derive(Debug)]
-struct CgroupState {
-    watcher: watch::Receiver<(Instant, cgroup::MemoryHistory)>,
-    /// If [`cgroup::MemoryHistory::avg_non_reclaimable`] exceeds `threshold`, we send upscale
-    /// requests.
-    threshold: u64,
-}
-
 /// Configuration for a `Runner`
 #[derive(Debug)]
 pub struct Config {
@@ -68,56 +62,16 @@ pub struct Config {
     /// upscale resource amounts (because we might not *actually* have been upscaled yet). This field
     /// should be removed once we have a better solution there.
     sys_buffer_bytes: u64,
-
-    /// Minimum fraction of total system memory reserved *before* the the cgroup threshold; in
-    /// other words, providing a ceiling for the highest value of the threshold by enforcing that
-    /// there's at least `cgroup_min_overhead_fraction` of the total memory remaining beyond the
-    /// threshold.
-    ///
-    /// For example, a value of `0.1` means that 10% of total memory must remain after exceeding
-    /// the threshold, so the value of the cgroup threshold would always be capped at 90% of total
-    /// memory.
-    ///
-    /// The default value of `0.15` means that we *guarantee* sending upscale requests if the
-    /// cgroup is using more than 85% of total memory (even if we're *not* separately reserving
-    /// memory for the file cache).
-    cgroup_min_overhead_fraction: f64,
-
-    cgroup_downscale_threshold_buffer_bytes: u64,
 }
 
 impl Default for Config {
     fn default() -> Self {
         Self {
             sys_buffer_bytes: 100 * MiB,
-            cgroup_min_overhead_fraction: 0.15,
-            cgroup_downscale_threshold_buffer_bytes: 100 * MiB,
         }
     }
 }
 
-impl Config {
-    fn cgroup_threshold(&self, total_mem: u64, file_cache_disk_size: u64) -> u64 {
-        // If the file cache is in tmpfs, then it will count towards shmem usage of the cgroup,
-        // and thus be non-reclaimable, so we should allow for additional memory usage.
-        //
-        // If the file cache sits on disk, our desired stable system state is for it to be fully
-        // page cached (its contents should only be paged to/from disk in situations where we can't
-        // upscale fast enough). Page-cached memory is reclaimable, so we need to lower the
-        // threshold for non-reclaimable memory so we scale up *before* the kernel starts paging
-        // out the file cache.
-        let memory_remaining_for_cgroup = total_mem.saturating_sub(file_cache_disk_size);
-
-        // Even if we're not separately making room for the file cache (if it's in tmpfs), we still
-        // want our threshold to be met gracefully instead of letting postgres get OOM-killed.
-        // So we guarantee that there's at least `cgroup_min_overhead_fraction` of total memory
-        // remaining above the threshold.
-        let max_threshold = (total_mem as f64 * (1.0 - self.cgroup_min_overhead_fraction)) as u64;
-
-        memory_remaining_for_cgroup.min(max_threshold)
-    }
-}
-
 impl Runner {
     /// Create a new monitor.
     #[tracing::instrument(skip_all, fields(?config, ?args))]
@@ -133,7 +87,12 @@ impl Runner {
             "invalid monitor Config: sys_buffer_bytes cannot be 0"
         );
 
-        let dispatcher = Dispatcher::new(ws)
+        // *NOTE*: the dispatcher and cgroup manager talk through these channels
+        // so make sure they each get the correct half, nothing is droppped, etc.
+        let (notified_send, notified_recv) = mpsc::channel(1);
+        let (requesting_send, requesting_recv) = mpsc::channel(1);
+
+        let dispatcher = Dispatcher::new(ws, notified_send, requesting_recv)
             .await
             .context("error creating new dispatcher")?;
 
@@ -147,18 +106,57 @@ impl Runner {
             kill,
         };
 
-        let mem = get_total_system_memory();
+        // If we have both the cgroup and file cache integrations enabled, it's possible for
+        // temporary failures to result in cgroup throttling (from memory.high), that in turn makes
+        // it near-impossible to connect to the file cache (because it times out). Unfortunately,
+        // we *do* still want to determine the file cache size before setting the cgroup's
+        // memory.high, so it's not as simple as just swapping the order.
+        //
+        // Instead, the resolution here is that on vm-monitor startup (note: happens on each
+        // connection from autoscaler-agent, possibly multiple times per compute_ctl lifecycle), we
+        // temporarily unset memory.high, to allow any existing throttling to dissipate. It's a bit
+        // of a hacky solution, but helps with reliability.
+        if let Some(name) = &args.cgroup {
+            // Best not to set up cgroup stuff more than once, so we'll initialize cgroup state
+            // now, and then set limits later.
+            info!("initializing cgroup");
 
-        let mut file_cache_disk_size = 0;
+            let (cgroup, cgroup_event_stream) = CgroupWatcher::new(name.clone(), requesting_send)
+                .context("failed to create cgroup manager")?;
+
+            info!("temporarily unsetting memory.high");
+
+            // Temporarily un-set cgroup memory.high; see above.
+            cgroup
+                .unset_memory_high()
+                .context("failed to unset memory.high")?;
+
+            let cgroup = Arc::new(cgroup);
+
+            let cgroup_clone = Arc::clone(&cgroup);
+            spawn_with_cancel(
+                token.clone(),
+                |_| error!("cgroup watcher terminated"),
+                async move { cgroup_clone.watch(notified_recv, cgroup_event_stream).await },
+            );
+
+            state.cgroup = Some(cgroup);
+        }
+
+        let mut file_cache_reserved_bytes = 0;
+        let mem = get_total_system_memory();
 
         // We need to process file cache initialization before cgroup initialization, so that the memory
         // allocated to the file cache is appropriately taken into account when we decide the cgroup's
         // memory limits.
         if let Some(connstr) = &args.pgconnstr {
             info!("initializing file cache");
-            let config = FileCacheConfig::default();
+            let config = match args.file_cache_on_disk {
+                true => FileCacheConfig::default_on_disk(),
+                false => FileCacheConfig::default_in_memory(),
+            };
 
-            let mut file_cache = FileCacheState::new(connstr, config, token.clone())
+            let mut file_cache = FileCacheState::new(connstr, config, token)
                 .await
                 .context("failed to create file cache")?;
 
@@ -183,37 +181,23 @@ impl Runner {
             if actual_size != new_size {
                 info!("file cache size actually got set to {actual_size}")
             }
+            // Mark the resources given to the file cache as reserved, but only if it's in memory.
+            if !args.file_cache_on_disk {
+                file_cache_reserved_bytes = actual_size;
+            }
 
-            file_cache_disk_size = actual_size;
             state.filecache = Some(file_cache);
         }
 
-        if let Some(name) = &args.cgroup {
-            // Best not to set up cgroup stuff more than once, so we'll initialize cgroup state
-            // now, and then set limits later.
-            info!("initializing cgroup");
+        if let Some(cgroup) = &state.cgroup {
+            let available = mem - file_cache_reserved_bytes;
+            let value = cgroup.config.calculate_memory_high_value(available);
 
-            let cgroup =
-                CgroupWatcher::new(name.clone()).context("failed to create cgroup manager")?;
+            info!(value, "setting memory.high");
 
-            let init_value = cgroup::MemoryHistory {
-                avg_non_reclaimable: 0,
-                samples_count: 0,
-                samples_span: Duration::ZERO,
-            };
-            let (hist_tx, hist_rx) = watch::channel((Instant::now(), init_value));
-
-            spawn_with_cancel(token, |_| error!("cgroup watcher terminated"), async move {
-                cgroup.watch(hist_tx).await
-            });
-
-            let threshold = state.config.cgroup_threshold(mem, file_cache_disk_size);
-            info!(threshold, "set initial cgroup threshold",);
-
-            state.cgroup = Some(CgroupState {
-                watcher: hist_rx,
-                threshold,
-            });
+            cgroup
+                .set_memory_high_bytes(value)
+                .context("failed to set cgroup memory.high")?;
         }
 
         Ok(state)
@@ -233,45 +217,28 @@ impl Runner {
 
         let requested_mem = target.mem;
         let usable_system_memory = requested_mem.saturating_sub(self.config.sys_buffer_bytes);
-        let expected_file_cache_size = self
+        let expected_file_cache_mem_usage = self
             .filecache
             .as_ref()
             .map(|file_cache| file_cache.config.calculate_cache_size(usable_system_memory))
             .unwrap_or(0);
+        let mut new_cgroup_mem_high = 0;
         if let Some(cgroup) = &self.cgroup {
-            let (last_time, last_history) = *cgroup.watcher.borrow();
-
-            // NB: The ordering of these conditions is intentional. During startup, we should deny
-            // downscaling until we have enough information to determine that it's safe to do so
-            // (i.e. enough samples have come in). But if it's been a while and we *still* haven't
-            // received any information, we should *fail* instead of just denying downscaling.
-            //
-            // `last_time` is set to `Instant::now()` on startup, so checking `last_time.elapsed()`
-            // serves double-duty: it trips if we haven't received *any* metrics for long enough,
-            // OR if we haven't received metrics *recently enough*.
-            //
-            // TODO: make the duration here configurable.
-            if last_time.elapsed() > Duration::from_secs(5) {
-                bail!("haven't gotten cgroup memory stats recently enough to determine downscaling information");
-            } else if last_history.samples_count <= 1 {
-                let status = "haven't received enough cgroup memory stats yet";
-                info!(status, "discontinuing downscale");
-                return Ok((false, status.to_owned()));
-            }
-
-            let new_threshold = self
+            new_cgroup_mem_high = cgroup
                 .config
-                .cgroup_threshold(usable_system_memory, expected_file_cache_size);
+                .calculate_memory_high_value(usable_system_memory - expected_file_cache_mem_usage);
 
-            let current = last_history.avg_non_reclaimable;
+            let current = cgroup
+                .current_memory_usage()
+                .context("failed to fetch cgroup memory")?;
 
-            if new_threshold < current + self.config.cgroup_downscale_threshold_buffer_bytes {
+            if new_cgroup_mem_high < current + cgroup.config.memory_high_buffer_bytes {
                 let status = format!(
-                    "{}: {} MiB (new threshold) < {} (current usage) + {} (downscale buffer)",
-                    "calculated memory threshold too low",
-                    bytes_to_mebibytes(new_threshold),
+                    "{}: {} MiB (new high) < {} (current usage) + {} (buffer)",
+                    "calculated memory.high too low",
+                    bytes_to_mebibytes(new_cgroup_mem_high),
                     bytes_to_mebibytes(current),
-                    bytes_to_mebibytes(self.config.cgroup_downscale_threshold_buffer_bytes)
+                    bytes_to_mebibytes(cgroup.config.memory_high_buffer_bytes)
                 );
 
                 info!(status, "discontinuing downscale");
@@ -282,33 +249,42 @@ impl Runner {
 
         // The downscaling has been approved. Downscale the file cache, then the cgroup.
         let mut status = vec![];
-        let mut file_cache_disk_size = 0;
+        let mut file_cache_mem_usage = 0;
         if let Some(file_cache) = &mut self.filecache {
             let actual_usage = file_cache
-                .set_file_cache_size(expected_file_cache_size)
+                .set_file_cache_size(expected_file_cache_mem_usage)
                 .await
                 .context("failed to set file cache size")?;
-            file_cache_disk_size = actual_usage;
+            if file_cache.config.in_memory {
+                file_cache_mem_usage = actual_usage;
+            }
             let message = format!(
-                "set file cache size to {} MiB",
+                "set file cache size to {} MiB (in memory = {})",
                 bytes_to_mebibytes(actual_usage),
+                file_cache.config.in_memory,
             );
             info!("downscale: {message}");
             status.push(message);
         }
 
-        if let Some(cgroup) = &mut self.cgroup {
-            let new_threshold = self
-                .config
-                .cgroup_threshold(usable_system_memory, file_cache_disk_size);
+        if let Some(cgroup) = &self.cgroup {
+            let available_memory = usable_system_memory - file_cache_mem_usage;
+
+            if file_cache_mem_usage != expected_file_cache_mem_usage {
+                new_cgroup_mem_high = cgroup.config.calculate_memory_high_value(available_memory);
+            }
+
+            // new_cgroup_mem_high is initialized to 0 but it is guaranteed to not be here
+            // since it is properly initialized in the previous cgroup if let block
+            cgroup
+                .set_memory_high_bytes(new_cgroup_mem_high)
+                .context("failed to set cgroup memory.high")?;
 
             let message = format!(
-                "set cgroup memory threshold from {} MiB to {} MiB, of new total {} MiB",
-                bytes_to_mebibytes(cgroup.threshold),
-                bytes_to_mebibytes(new_threshold),
-                bytes_to_mebibytes(usable_system_memory)
+                "set cgroup memory.high to {} MiB, of new max {} MiB",
+                bytes_to_mebibytes(new_cgroup_mem_high),
+                bytes_to_mebibytes(available_memory)
             );
-            cgroup.threshold = new_threshold;
             info!("downscale: {message}");
             status.push(message);
         }
@@ -329,7 +305,8 @@ impl Runner {
         let new_mem = resources.mem;
         let usable_system_memory = new_mem.saturating_sub(self.config.sys_buffer_bytes);
 
-        let mut file_cache_disk_size = 0;
+        // Get the file cache's expected contribution to the memory usage
+        let mut file_cache_mem_usage = 0;
         if let Some(file_cache) = &mut self.filecache {
             let expected_usage = file_cache.config.calculate_cache_size(usable_system_memory);
             info!(
@@ -342,7 +319,9 @@ impl Runner {
                 .set_file_cache_size(expected_usage)
                 .await
                 .context("failed to set file cache size")?;
-            file_cache_disk_size = actual_usage;
+            if file_cache.config.in_memory {
+                file_cache_mem_usage = actual_usage;
+            }
 
             if actual_usage != expected_usage {
                 warn!(
@@ -353,18 +332,18 @@ impl Runner {
             }
         }
 
-        if let Some(cgroup) = &mut self.cgroup {
-            let new_threshold = self
-                .config
-                .cgroup_threshold(usable_system_memory, file_cache_disk_size);
-
+        if let Some(cgroup) = &self.cgroup {
+            let available_memory = usable_system_memory - file_cache_mem_usage;
+            let new_cgroup_mem_high = cgroup.config.calculate_memory_high_value(available_memory);
             info!(
-                "set cgroup memory threshold from {} MiB to {} MiB of new total {} MiB",
-                bytes_to_mebibytes(cgroup.threshold),
-                bytes_to_mebibytes(new_threshold),
-                bytes_to_mebibytes(usable_system_memory)
+                target = bytes_to_mebibytes(new_cgroup_mem_high),
+                total = bytes_to_mebibytes(new_mem),
+                name = cgroup.path(),
+                "updating cgroup memory.high",
             );
-            cgroup.threshold = new_threshold;
+            cgroup
+                .set_memory_high_bytes(new_cgroup_mem_high)
+                .context("failed to set cgroup memory.high")?;
         }
 
         Ok(())
@@ -382,6 +361,10 @@ impl Runner {
                 self.handle_upscale(granted)
                     .await
                     .context("failed to handle upscale")?;
+                self.dispatcher
+                    .notify_upscale(Sequenced::new(granted))
+                    .await
+                    .context("failed to notify notify cgroup of upscale")?;
                 Ok(Some(OutboundMsg::new(
                     OutboundMsgKind::UpscaleConfirmation {},
                     id,
@@ -425,53 +408,33 @@ impl Runner {
                         Err(e) => bail!("failed to receive kill signal: {e}")
                     }
                 }
-
-                // New memory stats from the cgroup, *may* need to request upscaling, if we've
-                // exceeded the threshold
-                result = self.cgroup.as_mut().unwrap().watcher.changed(), if self.cgroup.is_some() => {
-                    result.context("failed to receive from cgroup memory stats watcher")?;
-
-                    let cgroup = self.cgroup.as_ref().unwrap();
-
-                    let (_time, cgroup_mem_stat) = *cgroup.watcher.borrow();
-
-                    // If we haven't exceeded the threshold, then we're all ok
-                    if cgroup_mem_stat.avg_non_reclaimable < cgroup.threshold {
-                        continue;
+                // we need to propagate an upscale request
+                request = self.dispatcher.request_upscale_events.recv(), if self.cgroup.is_some() => {
+                    if request.is_none() {
+                        bail!("failed to listen for upscale event from cgroup")
                     }
 
-                    // Otherwise, we generally want upscaling. But, if it's been less than 1 second
-                    // since the last time we requested upscaling, ignore the event, to avoid
-                    // spamming the agent.
+                    // If it's been less than 1 second since the last time we requested upscaling,
+                    // ignore the event, to avoid spamming the agent (otherwise, this can happen
+                    // ~1k times per second).
                     if let Some(t) = self.last_upscale_request_at {
                         let elapsed = t.elapsed();
                         if elapsed < Duration::from_secs(1) {
-                            info!(
-                                elapsed_millis = elapsed.as_millis(),
-                                avg_non_reclaimable = bytes_to_mebibytes(cgroup_mem_stat.avg_non_reclaimable),
-                                threshold = bytes_to_mebibytes(cgroup.threshold),
-                                "cgroup memory stats are high enough to upscale but too soon to forward the request, ignoring",
-                            );
+                            info!(elapsed_millis = elapsed.as_millis(), "cgroup asked for upscale but too soon to forward the request, ignoring");
                             continue;
                         }
                     }
 
                     self.last_upscale_request_at = Some(Instant::now());
 
-                    info!(
-                        avg_non_reclaimable = bytes_to_mebibytes(cgroup_mem_stat.avg_non_reclaimable),
-                        threshold = bytes_to_mebibytes(cgroup.threshold),
-                        "cgroup memory stats are high enough to upscale, requesting upscale",
-                    );
-
+                    info!("cgroup asking for upscale; forwarding request");
                     self.counter += 2; // Increment, preserving parity (i.e. keep the
                                        // counter odd). See the field comment for more.
                     self.dispatcher
                         .send(OutboundMsg::new(OutboundMsgKind::UpscaleRequest {}, self.counter))
                         .await
                         .context("failed to send message")?;
-                },
-
+                }
                 // there is a message from the agent
                 msg = self.dispatcher.source.next() => {
                     if let Some(msg) = msg {
@@ -499,14 +462,11 @@ impl Runner {
                                     Ok(Some(out)) => out,
                                     Ok(None) => continue,
                                     Err(e) => {
-                                        // use {:#} for our logging because the display impl only
-                                        // gives the outermost cause, and the debug impl
-                                        // pretty-prints the error, whereas {:#} contains all the
-                                        // causes, but is compact (no newlines).
-                                        warn!(error = format!("{e:#}"), "error handling message");
+                                        let error = e.to_string();
+                                        warn!(?error, "error handling message");
                                         OutboundMsg::new(
                                             OutboundMsgKind::InternalError {
-                                                error: e.to_string(),
+                                                error
                                             },
                                             message.id
                                         )

libs/walproposer/Cargo.toml

@@ -1,16 +0,0 @@
-[package]
-name = "walproposer"
-version = "0.1.0"
-edition.workspace = true
-license.workspace = true
-
-[dependencies]
-anyhow.workspace = true
-utils.workspace = true
-postgres_ffi.workspace = true
-
-workspace_hack.workspace = true
-
-[build-dependencies]
-anyhow.workspace = true
-bindgen.workspace = true

libs/walproposer/bindgen_deps.h

@@ -1 +0,0 @@
-#include "walproposer.h"

libs/walproposer/build.rs

@@ -1,113 +0,0 @@
-use std::{env, path::PathBuf, process::Command};
-
-use anyhow::{anyhow, Context};
-use bindgen::CargoCallbacks;
-
-fn main() -> anyhow::Result<()> {
-    // Tell cargo to invalidate the built crate whenever the wrapper changes
-    println!("cargo:rerun-if-changed=bindgen_deps.h");
-
-    // Finding the location of built libraries and Postgres C headers:
-    // - if POSTGRES_INSTALL_DIR is set look into it, otherwise look into `<project_root>/pg_install`
-    // - if there's a `bin/pg_config` file use it for getting include server, otherwise use `<project_root>/pg_install/{PG_MAJORVERSION}/include/postgresql/server`
-    let pg_install_dir = if let Some(postgres_install_dir) = env::var_os("POSTGRES_INSTALL_DIR") {
-        postgres_install_dir.into()
-    } else {
-        PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("../../pg_install")
-    };
-
-    let pg_install_abs = std::fs::canonicalize(pg_install_dir)?;
-    let walproposer_lib_dir = pg_install_abs.join("build/walproposer-lib");
-    let walproposer_lib_search_str = walproposer_lib_dir
-        .to_str()
-        .ok_or(anyhow!("Bad non-UTF path"))?;
-
-    let pgxn_neon = PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("../../pgxn/neon");
-    let pgxn_neon = std::fs::canonicalize(pgxn_neon)?;
-    let pgxn_neon = pgxn_neon.to_str().ok_or(anyhow!("Bad non-UTF path"))?;
-
-    println!("cargo:rustc-link-lib=static=pgport");
-    println!("cargo:rustc-link-lib=static=pgcommon");
-    println!("cargo:rustc-link-lib=static=walproposer");
-    println!("cargo:rustc-link-search={walproposer_lib_search_str}");
-
-    let pg_config_bin = pg_install_abs.join("v16").join("bin").join("pg_config");
-    let inc_server_path: String = if pg_config_bin.exists() {
-        let output = Command::new(pg_config_bin)
-            .arg("--includedir-server")
-            .output()
-            .context("failed to execute `pg_config --includedir-server`")?;
-
-        if !output.status.success() {
-            panic!("`pg_config --includedir-server` failed")
-        }
-
-        String::from_utf8(output.stdout)
-            .context("pg_config output is not UTF-8")?
-            .trim_end()
-            .into()
-    } else {
-        let server_path = pg_install_abs
-            .join("v16")
-            .join("include")
-            .join("postgresql")
-            .join("server")
-            .into_os_string();
-        server_path
-            .into_string()
-            .map_err(|s| anyhow!("Bad postgres server path {s:?}"))?
-    };
-
-    // The bindgen::Builder is the main entry point
-    // to bindgen, and lets you build up options for
-    // the resulting bindings.
-    let bindings = bindgen::Builder::default()
-        // The input header we would like to generate
-        // bindings for.
-        .header("bindgen_deps.h")
-        // Tell cargo to invalidate the built crate whenever any of the
-        // included header files changed.
-        .parse_callbacks(Box::new(CargoCallbacks))
-        .allowlist_type("WalProposer")
-        .allowlist_type("WalProposerConfig")
-        .allowlist_type("walproposer_api")
-        .allowlist_function("WalProposerCreate")
-        .allowlist_function("WalProposerStart")
-        .allowlist_function("WalProposerBroadcast")
-        .allowlist_function("WalProposerPoll")
-        .allowlist_function("WalProposerFree")
-        .allowlist_var("DEBUG5")
-        .allowlist_var("DEBUG4")
-        .allowlist_var("DEBUG3")
-        .allowlist_var("DEBUG2")
-        .allowlist_var("DEBUG1")
-        .allowlist_var("LOG")
-        .allowlist_var("INFO")
-        .allowlist_var("NOTICE")
-        .allowlist_var("WARNING")
-        .allowlist_var("ERROR")
-        .allowlist_var("FATAL")
-        .allowlist_var("PANIC")
-        .allowlist_var("WPEVENT")
-        .allowlist_var("WL_LATCH_SET")
-        .allowlist_var("WL_SOCKET_READABLE")
-        .allowlist_var("WL_SOCKET_WRITEABLE")
-        .allowlist_var("WL_TIMEOUT")
-        .allowlist_var("WL_SOCKET_CLOSED")
-        .allowlist_var("WL_SOCKET_MASK")
-        .clang_arg("-DWALPROPOSER_LIB")
-        .clang_arg(format!("-I{pgxn_neon}"))
-        .clang_arg(format!("-I{inc_server_path}"))
-        // Finish the builder and generate the bindings.
-        .generate()
-        // Unwrap the Result and panic on failure.
-        .expect("Unable to generate bindings");
-
-    // Write the bindings to the $OUT_DIR/bindings.rs file.
-    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("bindings.rs");
-    bindings
-        .write_to_file(out_path)
-        .expect("Couldn't write bindings!");
-
-    Ok(())
-}

libs/walproposer/src/api_bindings.rs

@@ -1,455 +0,0 @@
-#![allow(dead_code)]
-
-use std::ffi::CStr;
-use std::ffi::CString;
-
-use crate::bindings::uint32;
-use crate::bindings::walproposer_api;
-use crate::bindings::PGAsyncReadResult;
-use crate::bindings::PGAsyncWriteResult;
-use crate::bindings::Safekeeper;
-use crate::bindings::Size;
-use crate::bindings::StringInfoData;
-use crate::bindings::TimeLineID;
-use crate::bindings::TimestampTz;
-use crate::bindings::WalProposer;
-use crate::bindings::WalProposerConnStatusType;
-use crate::bindings::WalProposerConnectPollStatusType;
-use crate::bindings::WalProposerExecStatusType;
-use crate::bindings::WalproposerShmemState;
-use crate::bindings::XLogRecPtr;
-use crate::walproposer::ApiImpl;
-use crate::walproposer::WaitResult;
-
-extern "C" fn get_shmem_state(wp: *mut WalProposer) -> *mut WalproposerShmemState {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).get_shmem_state()
-    }
-}
-
-extern "C" fn start_streaming(wp: *mut WalProposer, startpos: XLogRecPtr) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).start_streaming(startpos)
-    }
-}
-
-extern "C" fn get_flush_rec_ptr(wp: *mut WalProposer) -> XLogRecPtr {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).get_flush_rec_ptr()
-    }
-}
-
-extern "C" fn get_current_timestamp(wp: *mut WalProposer) -> TimestampTz {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).get_current_timestamp()
-    }
-}
-
-extern "C" fn conn_error_message(sk: *mut Safekeeper) -> *mut ::std::os::raw::c_char {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        let msg = (*api).conn_error_message(&mut (*sk));
-        let msg = CString::new(msg).unwrap();
-        // TODO: fix leaking error message
-        msg.into_raw()
-    }
-}
-
-extern "C" fn conn_status(sk: *mut Safekeeper) -> WalProposerConnStatusType {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_status(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_connect_start(sk: *mut Safekeeper) {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_connect_start(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_connect_poll(sk: *mut Safekeeper) -> WalProposerConnectPollStatusType {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_connect_poll(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_send_query(sk: *mut Safekeeper, query: *mut ::std::os::raw::c_char) -> bool {
-    let query = unsafe { CStr::from_ptr(query) };
-    let query = query.to_str().unwrap();
-
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_send_query(&mut (*sk), query)
-    }
-}
-
-extern "C" fn conn_get_query_result(sk: *mut Safekeeper) -> WalProposerExecStatusType {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_get_query_result(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_flush(sk: *mut Safekeeper) -> ::std::os::raw::c_int {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_flush(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_finish(sk: *mut Safekeeper) {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_finish(&mut (*sk))
-    }
-}
-
-extern "C" fn conn_async_read(
-    sk: *mut Safekeeper,
-    buf: *mut *mut ::std::os::raw::c_char,
-    amount: *mut ::std::os::raw::c_int,
-) -> PGAsyncReadResult {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        let (res, result) = (*api).conn_async_read(&mut (*sk));
-
-        // This function has guarantee that returned buf will be valid until
-        // the next call. So we can store a Vec in each Safekeeper and reuse
-        // it on the next call.
-        let mut inbuf = take_vec_u8(&mut (*sk).inbuf).unwrap_or_default();
-
-        inbuf.clear();
-        inbuf.extend_from_slice(res);
-
-        // Put a Vec back to sk->inbuf and return data ptr.
-        *buf = store_vec_u8(&mut (*sk).inbuf, inbuf);
-        *amount = res.len() as i32;
-
-        result
-    }
-}
-
-extern "C" fn conn_async_write(
-    sk: *mut Safekeeper,
-    buf: *const ::std::os::raw::c_void,
-    size: usize,
-) -> PGAsyncWriteResult {
-    unsafe {
-        let buf = std::slice::from_raw_parts(buf as *const u8, size);
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_async_write(&mut (*sk), buf)
-    }
-}
-
-extern "C" fn conn_blocking_write(
-    sk: *mut Safekeeper,
-    buf: *const ::std::os::raw::c_void,
-    size: usize,
-) -> bool {
-    unsafe {
-        let buf = std::slice::from_raw_parts(buf as *const u8, size);
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).conn_blocking_write(&mut (*sk), buf)
-    }
-}
-
-extern "C" fn recovery_download(
-    sk: *mut Safekeeper,
-    _timeline: TimeLineID,
-    startpos: XLogRecPtr,
-    endpos: XLogRecPtr,
-) -> bool {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).recovery_download(&mut (*sk), startpos, endpos)
-    }
-}
-
-extern "C" fn wal_read(
-    sk: *mut Safekeeper,
-    buf: *mut ::std::os::raw::c_char,
-    startptr: XLogRecPtr,
-    count: Size,
-) {
-    unsafe {
-        let buf = std::slice::from_raw_parts_mut(buf as *mut u8, count);
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).wal_read(&mut (*sk), buf, startptr)
-    }
-}
-
-extern "C" fn wal_reader_allocate(sk: *mut Safekeeper) {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).wal_reader_allocate(&mut (*sk));
-    }
-}
-
-extern "C" fn free_event_set(wp: *mut WalProposer) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).free_event_set(&mut (*wp));
-    }
-}
-
-extern "C" fn init_event_set(wp: *mut WalProposer) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).init_event_set(&mut (*wp));
-    }
-}
-
-extern "C" fn update_event_set(sk: *mut Safekeeper, events: uint32) {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).update_event_set(&mut (*sk), events);
-    }
-}
-
-extern "C" fn add_safekeeper_event_set(sk: *mut Safekeeper, events: uint32) {
-    unsafe {
-        let callback_data = (*(*(*sk).wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).add_safekeeper_event_set(&mut (*sk), events);
-    }
-}
-
-extern "C" fn wait_event_set(
-    wp: *mut WalProposer,
-    timeout: ::std::os::raw::c_long,
-    event_sk: *mut *mut Safekeeper,
-    events: *mut uint32,
-) -> ::std::os::raw::c_int {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        let result = (*api).wait_event_set(&mut (*wp), timeout);
-        match result {
-            WaitResult::Latch => {
-                *event_sk = std::ptr::null_mut();
-                *events = crate::bindings::WL_LATCH_SET;
-                1
-            }
-            WaitResult::Timeout => {
-                *event_sk = std::ptr::null_mut();
-                *events = crate::bindings::WL_TIMEOUT;
-                0
-            }
-            WaitResult::Network(sk, event_mask) => {
-                *event_sk = sk;
-                *events = event_mask;
-                1
-            }
-        }
-    }
-}
-
-extern "C" fn strong_random(
-    wp: *mut WalProposer,
-    buf: *mut ::std::os::raw::c_void,
-    len: usize,
-) -> bool {
-    unsafe {
-        let buf = std::slice::from_raw_parts_mut(buf as *mut u8, len);
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).strong_random(buf)
-    }
-}
-
-extern "C" fn get_redo_start_lsn(wp: *mut WalProposer) -> XLogRecPtr {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).get_redo_start_lsn()
-    }
-}
-
-extern "C" fn finish_sync_safekeepers(wp: *mut WalProposer, lsn: XLogRecPtr) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).finish_sync_safekeepers(lsn)
-    }
-}
-
-extern "C" fn process_safekeeper_feedback(wp: *mut WalProposer, commit_lsn: XLogRecPtr) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).process_safekeeper_feedback(&mut (*wp), commit_lsn)
-    }
-}
-
-extern "C" fn confirm_wal_streamed(wp: *mut WalProposer, lsn: XLogRecPtr) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).confirm_wal_streamed(&mut (*wp), lsn)
-    }
-}
-
-extern "C" fn log_internal(
-    wp: *mut WalProposer,
-    level: ::std::os::raw::c_int,
-    line: *const ::std::os::raw::c_char,
-) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        let line = CStr::from_ptr(line);
-        let line = line.to_str().unwrap();
-        (*api).log_internal(&mut (*wp), Level::from(level as u32), line)
-    }
-}
-
-extern "C" fn after_election(wp: *mut WalProposer) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).after_election(&mut (*wp))
-    }
-}
-
-#[derive(Debug)]
-pub enum Level {
-    Debug5,
-    Debug4,
-    Debug3,
-    Debug2,
-    Debug1,
-    Log,
-    Info,
-    Notice,
-    Warning,
-    Error,
-    Fatal,
-    Panic,
-    WPEvent,
-}
-
-impl Level {
-    pub fn from(elevel: u32) -> Level {
-        use crate::bindings::*;
-
-        match elevel {
-            DEBUG5 => Level::Debug5,
-            DEBUG4 => Level::Debug4,
-            DEBUG3 => Level::Debug3,
-            DEBUG2 => Level::Debug2,
-            DEBUG1 => Level::Debug1,
-            LOG => Level::Log,
-            INFO => Level::Info,
-            NOTICE => Level::Notice,
-            WARNING => Level::Warning,
-            ERROR => Level::Error,
-            FATAL => Level::Fatal,
-            PANIC => Level::Panic,
-            WPEVENT => Level::WPEvent,
-            _ => panic!("unknown log level {}", elevel),
-        }
-    }
-}
-
-pub(crate) fn create_api() -> walproposer_api {
-    walproposer_api {
-        get_shmem_state: Some(get_shmem_state),
-        start_streaming: Some(start_streaming),
-        get_flush_rec_ptr: Some(get_flush_rec_ptr),
-        get_current_timestamp: Some(get_current_timestamp),
-        conn_error_message: Some(conn_error_message),
-        conn_status: Some(conn_status),
-        conn_connect_start: Some(conn_connect_start),
-        conn_connect_poll: Some(conn_connect_poll),
-        conn_send_query: Some(conn_send_query),
-        conn_get_query_result: Some(conn_get_query_result),
-        conn_flush: Some(conn_flush),
-        conn_finish: Some(conn_finish),
-        conn_async_read: Some(conn_async_read),
-        conn_async_write: Some(conn_async_write),
-        conn_blocking_write: Some(conn_blocking_write),
-        recovery_download: Some(recovery_download),
-        wal_read: Some(wal_read),
-        wal_reader_allocate: Some(wal_reader_allocate),
-        free_event_set: Some(free_event_set),
-        init_event_set: Some(init_event_set),
-        update_event_set: Some(update_event_set),
-        add_safekeeper_event_set: Some(add_safekeeper_event_set),
-        wait_event_set: Some(wait_event_set),
-        strong_random: Some(strong_random),
-        get_redo_start_lsn: Some(get_redo_start_lsn),
-        finish_sync_safekeepers: Some(finish_sync_safekeepers),
-        process_safekeeper_feedback: Some(process_safekeeper_feedback),
-        confirm_wal_streamed: Some(confirm_wal_streamed),
-        log_internal: Some(log_internal),
-        after_election: Some(after_election),
-    }
-}
-
-impl std::fmt::Display for Level {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        write!(f, "{:?}", self)
-    }
-}
-
-/// Take ownership of `Vec<u8>` from StringInfoData.
-pub(crate) fn take_vec_u8(pg: &mut StringInfoData) -> Option<Vec<u8>> {
-    if pg.data.is_null() {
-        return None;
-    }
-
-    let ptr = pg.data as *mut u8;
-    let length = pg.len as usize;
-    let capacity = pg.maxlen as usize;
-
-    pg.data = std::ptr::null_mut();
-    pg.len = 0;
-    pg.maxlen = 0;
-
-    unsafe { Some(Vec::from_raw_parts(ptr, length, capacity)) }
-}
-
-/// Store `Vec<u8>` in StringInfoData.
-fn store_vec_u8(pg: &mut StringInfoData, vec: Vec<u8>) -> *mut ::std::os::raw::c_char {
-    let ptr = vec.as_ptr() as *mut ::std::os::raw::c_char;
-    let length = vec.len();
-    let capacity = vec.capacity();
-
-    assert!(pg.data.is_null());
-
-    pg.data = ptr;
-    pg.len = length as i32;
-    pg.maxlen = capacity as i32;
-
-    std::mem::forget(vec);
-
-    ptr
-}

libs/walproposer/src/lib.rs

@@ -1,14 +0,0 @@
-pub mod bindings {
-    #![allow(non_upper_case_globals)]
-    #![allow(non_camel_case_types)]
-    #![allow(non_snake_case)]
-    // bindgen creates some unsafe code with no doc comments.
-    #![allow(clippy::missing_safety_doc)]
-    // noted at 1.63 that in many cases there's a u32 -> u32 transmutes in bindgen code.
-    #![allow(clippy::useless_transmute)]
-
-    include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
-}
-
-pub mod api_bindings;
-pub mod walproposer;

libs/walproposer/src/walproposer.rs

@@ -1,485 +0,0 @@
-use std::ffi::CString;
-
-use postgres_ffi::WAL_SEGMENT_SIZE;
-use utils::id::TenantTimelineId;
-
-use crate::{
-    api_bindings::{create_api, take_vec_u8, Level},
-    bindings::{
-        Safekeeper, WalProposer, WalProposerConfig, WalProposerCreate, WalProposerFree,
-        WalProposerStart,
-    },
-};
-
-/// Rust high-level wrapper for C walproposer API. Many methods are not required
-/// for simple cases, hence todo!() in default implementations.
-///
-/// Refer to `pgxn/neon/walproposer.h` for documentation.
-pub trait ApiImpl {
-    fn get_shmem_state(&self) -> &mut crate::bindings::WalproposerShmemState {
-        todo!()
-    }
-
-    fn start_streaming(&self, _startpos: u64) {
-        todo!()
-    }
-
-    fn get_flush_rec_ptr(&self) -> u64 {
-        todo!()
-    }
-
-    fn get_current_timestamp(&self) -> i64 {
-        todo!()
-    }
-
-    fn conn_error_message(&self, _sk: &mut Safekeeper) -> String {
-        todo!()
-    }
-
-    fn conn_status(&self, _sk: &mut Safekeeper) -> crate::bindings::WalProposerConnStatusType {
-        todo!()
-    }
-
-    fn conn_connect_start(&self, _sk: &mut Safekeeper) {
-        todo!()
-    }
-
-    fn conn_connect_poll(
-        &self,
-        _sk: &mut Safekeeper,
-    ) -> crate::bindings::WalProposerConnectPollStatusType {
-        todo!()
-    }
-
-    fn conn_send_query(&self, _sk: &mut Safekeeper, _query: &str) -> bool {
-        todo!()
-    }
-
-    fn conn_get_query_result(
-        &self,
-        _sk: &mut Safekeeper,
-    ) -> crate::bindings::WalProposerExecStatusType {
-        todo!()
-    }
-
-    fn conn_flush(&self, _sk: &mut Safekeeper) -> i32 {
-        todo!()
-    }
-
-    fn conn_finish(&self, _sk: &mut Safekeeper) {
-        todo!()
-    }
-
-    fn conn_async_read(&self, _sk: &mut Safekeeper) -> (&[u8], crate::bindings::PGAsyncReadResult) {
-        todo!()
-    }
-
-    fn conn_async_write(
-        &self,
-        _sk: &mut Safekeeper,
-        _buf: &[u8],
-    ) -> crate::bindings::PGAsyncWriteResult {
-        todo!()
-    }
-
-    fn conn_blocking_write(&self, _sk: &mut Safekeeper, _buf: &[u8]) -> bool {
-        todo!()
-    }
-
-    fn recovery_download(&self, _sk: &mut Safekeeper, _startpos: u64, _endpos: u64) -> bool {
-        todo!()
-    }
-
-    fn wal_read(&self, _sk: &mut Safekeeper, _buf: &mut [u8], _startpos: u64) {
-        todo!()
-    }
-
-    fn wal_reader_allocate(&self, _sk: &mut Safekeeper) {
-        todo!()
-    }
-
-    fn free_event_set(&self, _wp: &mut WalProposer) {
-        todo!()
-    }
-
-    fn init_event_set(&self, _wp: &mut WalProposer) {
-        todo!()
-    }
-
-    fn update_event_set(&self, _sk: &mut Safekeeper, _events_mask: u32) {
-        todo!()
-    }
-
-    fn add_safekeeper_event_set(&self, _sk: &mut Safekeeper, _events_mask: u32) {
-        todo!()
-    }
-
-    fn wait_event_set(&self, _wp: &mut WalProposer, _timeout_millis: i64) -> WaitResult {
-        todo!()
-    }
-
-    fn strong_random(&self, _buf: &mut [u8]) -> bool {
-        todo!()
-    }
-
-    fn get_redo_start_lsn(&self) -> u64 {
-        todo!()
-    }
-
-    fn finish_sync_safekeepers(&self, _lsn: u64) {
-        todo!()
-    }
-
-    fn process_safekeeper_feedback(&self, _wp: &mut WalProposer, _commit_lsn: u64) {
-        todo!()
-    }
-
-    fn confirm_wal_streamed(&self, _wp: &mut WalProposer, _lsn: u64) {
-        todo!()
-    }
-
-    fn log_internal(&self, _wp: &mut WalProposer, _level: Level, _msg: &str) {
-        todo!()
-    }
-
-    fn after_election(&self, _wp: &mut WalProposer) {
-        todo!()
-    }
-}
-
-pub enum WaitResult {
-    Latch,
-    Timeout,
-    Network(*mut Safekeeper, u32),
-}
-
-pub struct Config {
-    /// Tenant and timeline id
-    pub ttid: TenantTimelineId,
-    /// List of safekeepers in format `host:port`
-    pub safekeepers_list: Vec<String>,
-    /// Safekeeper reconnect timeout in milliseconds
-    pub safekeeper_reconnect_timeout: i32,
-    /// Safekeeper connection timeout in milliseconds
-    pub safekeeper_connection_timeout: i32,
-    /// walproposer mode, finish when all safekeepers are synced or subscribe
-    /// to WAL streaming
-    pub sync_safekeepers: bool,
-}
-
-/// WalProposer main struct. C methods are reexported as Rust functions.
-pub struct Wrapper {
-    wp: *mut WalProposer,
-    _safekeepers_list_vec: Vec<u8>,
-}
-
-impl Wrapper {
-    pub fn new(api: Box<dyn ApiImpl>, config: Config) -> Wrapper {
-        let neon_tenant = CString::new(config.ttid.tenant_id.to_string())
-            .unwrap()
-            .into_raw();
-        let neon_timeline = CString::new(config.ttid.timeline_id.to_string())
-            .unwrap()
-            .into_raw();
-
-        let mut safekeepers_list_vec = CString::new(config.safekeepers_list.join(","))
-            .unwrap()
-            .into_bytes_with_nul();
-        assert!(safekeepers_list_vec.len() == safekeepers_list_vec.capacity());
-        let safekeepers_list = safekeepers_list_vec.as_mut_ptr() as *mut i8;
-
-        let callback_data = Box::into_raw(Box::new(api)) as *mut ::std::os::raw::c_void;
-
-        let c_config = WalProposerConfig {
-            neon_tenant,
-            neon_timeline,
-            safekeepers_list,
-            safekeeper_reconnect_timeout: config.safekeeper_reconnect_timeout,
-            safekeeper_connection_timeout: config.safekeeper_connection_timeout,
-            wal_segment_size: WAL_SEGMENT_SIZE as i32, // default 16MB
-            syncSafekeepers: config.sync_safekeepers,
-            systemId: 0,
-            pgTimeline: 1,
-            callback_data,
-        };
-        let c_config = Box::into_raw(Box::new(c_config));
-
-        let api = create_api();
-        let wp = unsafe { WalProposerCreate(c_config, api) };
-        Wrapper {
-            wp,
-            _safekeepers_list_vec: safekeepers_list_vec,
-        }
-    }
-
-    pub fn start(&self) {
-        unsafe { WalProposerStart(self.wp) }
-    }
-}
-
-impl Drop for Wrapper {
-    fn drop(&mut self) {
-        unsafe {
-            let config = (*self.wp).config;
-            drop(Box::from_raw(
-                (*config).callback_data as *mut Box<dyn ApiImpl>,
-            ));
-            drop(CString::from_raw((*config).neon_tenant));
-            drop(CString::from_raw((*config).neon_timeline));
-            drop(Box::from_raw(config));
-
-            for i in 0..(*self.wp).n_safekeepers {
-                let sk = &mut (*self.wp).safekeeper[i as usize];
-                take_vec_u8(&mut sk.inbuf);
-            }
-
-            WalProposerFree(self.wp);
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use std::{
-        cell::Cell,
-        sync::{atomic::AtomicUsize, mpsc::sync_channel},
-    };
-
-    use utils::id::TenantTimelineId;
-
-    use crate::{api_bindings::Level, walproposer::Wrapper};
-
-    use super::ApiImpl;
-
-    #[derive(Clone, Copy, Debug)]
-    struct WaitEventsData {
-        sk: *mut crate::bindings::Safekeeper,
-        event_mask: u32,
-    }
-
-    struct MockImpl {
-        // data to return from wait_event_set
-        wait_events: Cell<WaitEventsData>,
-        // walproposer->safekeeper messages
-        expected_messages: Vec<Vec<u8>>,
-        expected_ptr: AtomicUsize,
-        // safekeeper->walproposer messages
-        safekeeper_replies: Vec<Vec<u8>>,
-        replies_ptr: AtomicUsize,
-        // channel to send LSN to the main thread
-        sync_channel: std::sync::mpsc::SyncSender<u64>,
-    }
-
-    impl MockImpl {
-        fn check_walproposer_msg(&self, msg: &[u8]) {
-            let ptr = self
-                .expected_ptr
-                .fetch_add(1, std::sync::atomic::Ordering::SeqCst);
-
-            if ptr >= self.expected_messages.len() {
-                panic!("unexpected message from walproposer");
-            }
-
-            let expected_msg = &self.expected_messages[ptr];
-            assert_eq!(msg, expected_msg.as_slice());
-        }
-
-        fn next_safekeeper_reply(&self) -> &[u8] {
-            let ptr = self
-                .replies_ptr
-                .fetch_add(1, std::sync::atomic::Ordering::SeqCst);
-
-            if ptr >= self.safekeeper_replies.len() {
-                panic!("no more safekeeper replies");
-            }
-
-            &self.safekeeper_replies[ptr]
-        }
-    }
-
-    impl ApiImpl for MockImpl {
-        fn get_current_timestamp(&self) -> i64 {
-            println!("get_current_timestamp");
-            0
-        }
-
-        fn conn_status(
-            &self,
-            _: &mut crate::bindings::Safekeeper,
-        ) -> crate::bindings::WalProposerConnStatusType {
-            println!("conn_status");
-            crate::bindings::WalProposerConnStatusType_WP_CONNECTION_OK
-        }
-
-        fn conn_connect_start(&self, _: &mut crate::bindings::Safekeeper) {
-            println!("conn_connect_start");
-        }
-
-        fn conn_connect_poll(
-            &self,
-            _: &mut crate::bindings::Safekeeper,
-        ) -> crate::bindings::WalProposerConnectPollStatusType {
-            println!("conn_connect_poll");
-            crate::bindings::WalProposerConnectPollStatusType_WP_CONN_POLLING_OK
-        }
-
-        fn conn_send_query(&self, _: &mut crate::bindings::Safekeeper, query: &str) -> bool {
-            println!("conn_send_query: {}", query);
-            true
-        }
-
-        fn conn_get_query_result(
-            &self,
-            _: &mut crate::bindings::Safekeeper,
-        ) -> crate::bindings::WalProposerExecStatusType {
-            println!("conn_get_query_result");
-            crate::bindings::WalProposerExecStatusType_WP_EXEC_SUCCESS_COPYBOTH
-        }
-
-        fn conn_async_read(
-            &self,
-            _: &mut crate::bindings::Safekeeper,
-        ) -> (&[u8], crate::bindings::PGAsyncReadResult) {
-            println!("conn_async_read");
-            let reply = self.next_safekeeper_reply();
-            println!("conn_async_read result: {:?}", reply);
-            (
-                reply,
-                crate::bindings::PGAsyncReadResult_PG_ASYNC_READ_SUCCESS,
-            )
-        }
-
-        fn conn_blocking_write(&self, _: &mut crate::bindings::Safekeeper, buf: &[u8]) -> bool {
-            println!("conn_blocking_write: {:?}", buf);
-            self.check_walproposer_msg(buf);
-            true
-        }
-
-        fn wal_reader_allocate(&self, _: &mut crate::bindings::Safekeeper) {
-            println!("wal_reader_allocate")
-        }
-
-        fn free_event_set(&self, _: &mut crate::bindings::WalProposer) {
-            println!("free_event_set")
-        }
-
-        fn init_event_set(&self, _: &mut crate::bindings::WalProposer) {
-            println!("init_event_set")
-        }
-
-        fn update_event_set(&self, sk: &mut crate::bindings::Safekeeper, event_mask: u32) {
-            println!(
-                "update_event_set, sk={:?}, events_mask={:#b}",
-                sk as *mut crate::bindings::Safekeeper, event_mask
-            );
-            self.wait_events.set(WaitEventsData { sk, event_mask });
-        }
-
-        fn add_safekeeper_event_set(&self, sk: &mut crate::bindings::Safekeeper, event_mask: u32) {
-            println!(
-                "add_safekeeper_event_set, sk={:?}, events_mask={:#b}",
-                sk as *mut crate::bindings::Safekeeper, event_mask
-            );
-            self.wait_events.set(WaitEventsData { sk, event_mask });
-        }
-
-        fn wait_event_set(
-            &self,
-            _: &mut crate::bindings::WalProposer,
-            timeout_millis: i64,
-        ) -> super::WaitResult {
-            let data = self.wait_events.get();
-            println!(
-                "wait_event_set, timeout_millis={}, res={:?}",
-                timeout_millis, data
-            );
-            super::WaitResult::Network(data.sk, data.event_mask)
-        }
-
-        fn strong_random(&self, buf: &mut [u8]) -> bool {
-            println!("strong_random");
-            buf.fill(0);
-            true
-        }
-
-        fn finish_sync_safekeepers(&self, lsn: u64) {
-            self.sync_channel.send(lsn).unwrap();
-            panic!("sync safekeepers finished at lsn={}", lsn);
-        }
-
-        fn log_internal(&self, _wp: &mut crate::bindings::WalProposer, level: Level, msg: &str) {
-            println!("walprop_log[{}] {}", level, msg);
-        }
-
-        fn after_election(&self, _wp: &mut crate::bindings::WalProposer) {
-            println!("after_election");
-        }
-    }
-
-    /// Test that walproposer can successfully connect to safekeeper and finish
-    /// sync_safekeepers. API is mocked in MockImpl.
-    ///
-    /// Run this test with valgrind to detect leaks:
-    /// `valgrind --leak-check=full target/debug/deps/walproposer-<build>`
-    #[test]
-    fn test_simple_sync_safekeepers() -> anyhow::Result<()> {
-        let ttid = TenantTimelineId::new(
-            "9e4c8f36063c6c6e93bc20d65a820f3d".parse()?,
-            "9e4c8f36063c6c6e93bc20d65a820f3d".parse()?,
-        );
-
-        let (sender, receiver) = sync_channel(1);
-
-        let my_impl: Box<dyn ApiImpl> = Box::new(MockImpl {
-            wait_events: Cell::new(WaitEventsData {
-                sk: std::ptr::null_mut(),
-                event_mask: 0,
-            }),
-            expected_messages: vec![
-                // Greeting(ProposerGreeting { protocol_version: 2, pg_version: 160000, proposer_id: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], system_id: 0, timeline_id: 9e4c8f36063c6c6e93bc20d65a820f3d, tenant_id: 9e4c8f36063c6c6e93bc20d65a820f3d, tli: 1, wal_seg_size: 16777216 })
-                vec![
-                    103, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 113, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-                    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 158, 76, 143, 54, 6, 60, 108, 110,
-                    147, 188, 32, 214, 90, 130, 15, 61, 158, 76, 143, 54, 6, 60, 108, 110, 147,
-                    188, 32, 214, 90, 130, 15, 61, 1, 0, 0, 0, 0, 0, 0, 1,
-                ],
-                // VoteRequest(VoteRequest { term: 3 })
-                vec![
-                    118, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-                    0, 0, 0, 0, 0, 0,
-                ],
-            ],
-            expected_ptr: AtomicUsize::new(0),
-            safekeeper_replies: vec![
-                // Greeting(AcceptorGreeting { term: 2, node_id: NodeId(1) })
-                vec![
-                    103, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0,
-                ],
-                // VoteResponse(VoteResponse { term: 3, vote_given: 1, flush_lsn: 0/539, truncate_lsn: 0/539, term_history: [(2, 0/539)], timeline_start_lsn: 0/539 })
-                vec![
-                    118, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 57,
-                    5, 0, 0, 0, 0, 0, 0, 57, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0,
-                    0, 57, 5, 0, 0, 0, 0, 0, 0, 57, 5, 0, 0, 0, 0, 0, 0,
-                ],
-            ],
-            replies_ptr: AtomicUsize::new(0),
-            sync_channel: sender,
-        });
-        let config = crate::walproposer::Config {
-            ttid,
-            safekeepers_list: vec!["localhost:5000".to_string()],
-            safekeeper_reconnect_timeout: 1000,
-            safekeeper_connection_timeout: 10000,
-            sync_safekeepers: true,
-        };
-
-        let wp = Wrapper::new(my_impl, config);
-
-        // walproposer will panic when it finishes sync_safekeepers
-        std::panic::catch_unwind(|| wp.start()).unwrap_err();
-        // validate the resulting LSN
-        assert_eq!(receiver.recv()?, 1337);
-        Ok(())
-        // drop() will free up resources here
-    }
-}

pageserver/benches/bench_walredo.rs

@@ -11,7 +11,10 @@ use std::sync::{Arc, Barrier};
 
 use bytes::{Buf, Bytes};
 use pageserver::{
-    config::PageServerConf, repository::Key, walrecord::NeonWalRecord, walredo::PostgresRedoManager,
+    config::PageServerConf,
+    repository::Key,
+    walrecord::NeonWalRecord,
+    walredo::{PostgresRedoManager, WalRedoError},
 };
 use utils::{id::TenantId, lsn::Lsn};
 
@@ -32,15 +35,9 @@ fn redo_scenarios(c: &mut Criterion) {
 
     let manager = Arc::new(manager);
 
-    {
-        let rt = tokio::runtime::Builder::new_current_thread()
-            .enable_all()
-            .build()
-            .unwrap();
-        tracing::info!("executing first");
-        short().execute(rt.handle(), &manager).unwrap();
-        tracing::info!("first executed");
-    }
+    tracing::info!("executing first");
+    short().execute(&manager).unwrap();
+    tracing::info!("first executed");
 
     let thread_counts = [1, 2, 4, 8, 16];
 
@@ -83,14 +80,9 @@ fn add_multithreaded_walredo_requesters(
     assert_ne!(threads, 0);
 
     if threads == 1 {
-        let rt = tokio::runtime::Builder::new_current_thread()
-            .enable_all()
-            .build()
-            .unwrap();
-        let handle = rt.handle();
         b.iter_batched_ref(
             || Some(input_factory()),
-            |input| execute_all(input.take(), handle, manager),
+            |input| execute_all(input.take(), manager),
             criterion::BatchSize::PerIteration,
         );
     } else {
@@ -106,26 +98,19 @@ fn add_multithreaded_walredo_requesters(
                     let manager = manager.clone();
                     let barrier = barrier.clone();
                     let work_rx = work_rx.clone();
-                    move || {
-                        let rt = tokio::runtime::Builder::new_current_thread()
-                            .enable_all()
-                            .build()
-                            .unwrap();
-                        let handle = rt.handle();
-                        loop {
-                            // queue up and wait if we want to go another round
-                            if work_rx.lock().unwrap().recv().is_err() {
-                                break;
-                            }
-
-                            let input = Some(input_factory());
-
-                            barrier.wait();
-
-                            execute_all(input, handle, &manager).unwrap();
-
-                            barrier.wait();
+                    move || loop {
+                        // queue up and wait if we want to go another round
+                        if work_rx.lock().unwrap().recv().is_err() {
+                            break;
                         }
+
+                        let input = Some(input_factory());
+
+                        barrier.wait();
+
+                        execute_all(input, &manager).unwrap();
+
+                        barrier.wait();
                     }
                 })
             })
@@ -167,19 +152,15 @@ impl Drop for JoinOnDrop {
     }
 }
 
-fn execute_all<I>(
-    input: I,
-    handle: &tokio::runtime::Handle,
-    manager: &PostgresRedoManager,
-) -> anyhow::Result<()>
+fn execute_all<I>(input: I, manager: &PostgresRedoManager) -> Result<(), WalRedoError>
 where
     I: IntoIterator<Item = Request>,
 {
     // just fire all requests as fast as possible
     input.into_iter().try_for_each(|req| {
-        let page = req.execute(handle, manager)?;
+        let page = req.execute(manager)?;
         assert_eq!(page.remaining(), 8192);
-        anyhow::Ok(())
+        Ok::<_, WalRedoError>(())
     })
 }
 
@@ -492,11 +473,9 @@ struct Request {
 }
 
 impl Request {
-    fn execute(
-        self,
-        rt: &tokio::runtime::Handle,
-        manager: &PostgresRedoManager,
-    ) -> anyhow::Result<Bytes> {
+    fn execute(self, manager: &PostgresRedoManager) -> Result<Bytes, WalRedoError> {
+        use pageserver::walredo::WalRedoManager;
+
         let Request {
             key,
             lsn,
@@ -505,6 +484,6 @@ impl Request {
             pg_version,
         } = self;
 
-        rt.block_on(manager.request_redo(key, lsn, base_img, records, pg_version))
+        manager.request_redo(key, lsn, base_img, records, pg_version)
     }
 }

pageserver/src/basebackup.rs

@@ -13,7 +13,6 @@
 use anyhow::{anyhow, bail, ensure, Context};
 use bytes::{BufMut, BytesMut};
 use fail::fail_point;
-use postgres_ffi::pg_constants;
 use std::fmt::Write as FmtWrite;
 use std::time::SystemTime;
 use tokio::io;
@@ -181,7 +180,6 @@ where
             }
         }
 
-        let mut min_restart_lsn: Lsn = Lsn::MAX;
         // Create tablespace directories
         for ((spcnode, dbnode), has_relmap_file) in
             self.timeline.list_dbdirs(self.lsn, self.ctx).await?
@@ -215,34 +213,6 @@ where
                     self.add_rel(rel, rel).await?;
                 }
             }
-
-            for (path, content) in self.timeline.list_aux_files(self.lsn, self.ctx).await? {
-                if path.starts_with("pg_replslot") {
-                    let offs = pg_constants::REPL_SLOT_ON_DISK_OFFSETOF_RESTART_LSN;
-                    let restart_lsn = Lsn(u64::from_le_bytes(
-                        content[offs..offs + 8].try_into().unwrap(),
-                    ));
-                    info!("Replication slot {} restart LSN={}", path, restart_lsn);
-                    min_restart_lsn = Lsn::min(min_restart_lsn, restart_lsn);
-                }
-                let header = new_tar_header(&path, content.len() as u64)?;
-                self.ar
-                    .append(&header, &*content)
-                    .await
-                    .context("could not add aux file to basebackup tarball")?;
-            }
-        }
-        if min_restart_lsn != Lsn::MAX {
-            info!(
-                "Min restart LSN for logical replication is {}",
-                min_restart_lsn
-            );
-            let data = min_restart_lsn.0.to_le_bytes();
-            let header = new_tar_header("restart.lsn", data.len() as u64)?;
-            self.ar
-                .append(&header, &data[..])
-                .await
-                .context("could not add restart.lsn file to basebackup tarball")?;
         }
         for xid in self
             .timeline

pageserver/src/bin/pageserver.rs

@@ -2,7 +2,6 @@
 
 use std::env::{var, VarError};
 use std::sync::Arc;
-use std::time::Duration;
 use std::{env, ops::ControlFlow, str::FromStr};
 
 use anyhow::{anyhow, Context};
@@ -34,12 +33,11 @@ use postgres_backend::AuthType;
 use utils::logging::TracingErrorLayerEnablement;
 use utils::signals::ShutdownSignals;
 use utils::{
-    auth::JwtAuth, logging, project_build_tag, project_git_version, sentry_init::init_sentry,
-    signals::Signal, tcp_listener,
+    auth::JwtAuth, logging, project_git_version, sentry_init::init_sentry, signals::Signal,
+    tcp_listener,
 };
 
 project_git_version!(GIT_VERSION);
-project_build_tag!(BUILD_TAG);
 
 const PID_FILE_NAME: &str = "pageserver.pid";
 
@@ -202,51 +200,6 @@ fn initialize_config(
     })
 }
 
-struct WaitForPhaseResult<F: std::future::Future + Unpin> {
-    timeout_remaining: Duration,
-    skipped: Option<F>,
-}
-
-/// During startup, we apply a timeout to our waits for readiness, to avoid
-/// stalling the whole service if one Tenant experiences some problem.  Each
-/// phase may consume some of the timeout: this function returns the updated
-/// timeout for use in the next call.
-async fn wait_for_phase<F>(phase: &str, mut fut: F, timeout: Duration) -> WaitForPhaseResult<F>
-where
-    F: std::future::Future + Unpin,
-{
-    let initial_t = Instant::now();
-    let skipped = match tokio::time::timeout(timeout, &mut fut).await {
-        Ok(_) => None,
-        Err(_) => {
-            tracing::info!(
-                timeout_millis = timeout.as_millis(),
-                %phase,
-                "Startup phase timed out, proceeding anyway"
-            );
-            Some(fut)
-        }
-    };
-
-    WaitForPhaseResult {
-        timeout_remaining: timeout
-            .checked_sub(Instant::now().duration_since(initial_t))
-            .unwrap_or(Duration::ZERO),
-        skipped,
-    }
-}
-
-fn startup_checkpoint(started_at: Instant, phase: &str, human_phase: &str) {
-    let elapsed = started_at.elapsed();
-    let secs = elapsed.as_secs_f64();
-    STARTUP_DURATION.with_label_values(&[phase]).set(secs);
-
-    info!(
-        elapsed_ms = elapsed.as_millis(),
-        "{human_phase} ({secs:.3}s since start)"
-    )
-}
-
 fn start_pageserver(
     launch_ts: &'static LaunchTimestamp,
     conf: &'static PageServerConf,
@@ -254,17 +207,26 @@ fn start_pageserver(
     // Monotonic time for later calculating startup duration
     let started_startup_at = Instant::now();
 
+    let startup_checkpoint = move |phase: &str, human_phase: &str| {
+        let elapsed = started_startup_at.elapsed();
+        let secs = elapsed.as_secs_f64();
+        STARTUP_DURATION.with_label_values(&[phase]).set(secs);
+        info!(
+            elapsed_ms = elapsed.as_millis(),
+            "{human_phase} ({secs:.3}s since start)"
+        )
+    };
+
     // Print version and launch timestamp to the log,
     // and expose them as prometheus metrics.
     // A changed version string indicates changed software.
     // A changed launch timestamp indicates a pageserver restart.
     info!(
-        "version: {} launch_timestamp: {} build_tag: {}",
+        "version: {} launch_timestamp: {}",
         version(),
-        launch_ts.to_string(),
-        BUILD_TAG,
+        launch_ts.to_string()
     );
-    set_build_info_metric(GIT_VERSION, BUILD_TAG);
+    set_build_info_metric(GIT_VERSION);
     set_launch_timestamp_metric(launch_ts);
     pageserver::preinitialize_metrics();
 
@@ -379,7 +341,7 @@ fn start_pageserver(
 
     // Up to this point no significant I/O has been done: this should have been fast.  Record
     // duration prior to starting I/O intensive phase of startup.
-    startup_checkpoint(started_startup_at, "initial", "Starting loading tenants");
+    startup_checkpoint("initial", "Starting loading tenants");
     STARTUP_IS_LOADING.set(1);
 
     // Startup staging or optimizing:
@@ -393,7 +355,6 @@ fn start_pageserver(
     // consumer side) will be dropped once we can start the background jobs. Currently it is behind
     // completing all initial logical size calculations (init_logical_size_done_rx) and a timeout
     // (background_task_maximum_delay).
-    let (init_remote_done_tx, init_remote_done_rx) = utils::completion::channel();
     let (init_done_tx, init_done_rx) = utils::completion::channel();
 
     let (init_logical_size_done_tx, init_logical_size_done_rx) = utils::completion::channel();
@@ -401,8 +362,7 @@ fn start_pageserver(
     let (background_jobs_can_start, background_jobs_barrier) = utils::completion::channel();
 
     let order = pageserver::InitializationOrder {
-        initial_tenant_load_remote: Some(init_done_tx),
-        initial_tenant_load: Some(init_remote_done_tx),
+        initial_tenant_load: Some(init_done_tx),
         initial_logical_size_can_start: init_done_rx.clone(),
         initial_logical_size_attempt: Some(init_logical_size_done_tx),
         background_jobs_can_start: background_jobs_barrier.clone(),
@@ -426,93 +386,55 @@ fn start_pageserver(
         let shutdown_pageserver = shutdown_pageserver.clone();
         let drive_init = async move {
             // NOTE: unlike many futures in pageserver, this one is cancellation-safe
-            let guard = scopeguard::guard_on_success((), |_| {
-                tracing::info!("Cancelled before initial load completed")
-            });
+            let guard = scopeguard::guard_on_success((), |_| tracing::info!("Cancelled before initial load completed"));
 
-            let timeout = conf.background_task_maximum_delay;
-
-            let init_remote_done = std::pin::pin!(async {
-                init_remote_done_rx.wait().await;
-                startup_checkpoint(
-                    started_startup_at,
-                    "initial_tenant_load_remote",
-                    "Remote part of initial load completed",
-                );
-            });
-
-            let WaitForPhaseResult {
-                timeout_remaining: timeout,
-                skipped: init_remote_skipped,
-            } = wait_for_phase("initial_tenant_load_remote", init_remote_done, timeout).await;
-
-            let init_load_done = std::pin::pin!(async {
-                init_done_rx.wait().await;
-                startup_checkpoint(
-                    started_startup_at,
-                    "initial_tenant_load",
-                    "Initial load completed",
-                );
-                STARTUP_IS_LOADING.set(0);
-            });
-
-            let WaitForPhaseResult {
-                timeout_remaining: timeout,
-                skipped: init_load_skipped,
-            } = wait_for_phase("initial_tenant_load", init_load_done, timeout).await;
+            init_done_rx.wait().await;
+            startup_checkpoint("initial_tenant_load", "Initial load completed");
+            STARTUP_IS_LOADING.set(0);
 
             // initial logical sizes can now start, as they were waiting on init_done_rx.
 
             scopeguard::ScopeGuard::into_inner(guard);
 
-            let guard = scopeguard::guard_on_success((), |_| {
-                tracing::info!("Cancelled before initial logical sizes completed")
-            });
+            let mut init_sizes_done = std::pin::pin!(init_logical_size_done_rx.wait());
 
-            let logical_sizes_done = std::pin::pin!(async {
-                init_logical_size_done_rx.wait().await;
-                startup_checkpoint(
-                    started_startup_at,
-                    "initial_logical_sizes",
-                    "Initial logical sizes completed",
-                );
-            });
+            let timeout = conf.background_task_maximum_delay;
 
-            let WaitForPhaseResult {
-                timeout_remaining: _,
-                skipped: logical_sizes_skipped,
-            } = wait_for_phase("initial_logical_sizes", logical_sizes_done, timeout).await;
+            let guard = scopeguard::guard_on_success((), |_| tracing::info!("Cancelled before initial logical sizes completed"));
+
+            let init_sizes_done = match tokio::time::timeout(timeout, &mut init_sizes_done).await {
+                Ok(_) => {
+                    startup_checkpoint("initial_logical_sizes", "Initial logical sizes completed");
+                    None
+                }
+                Err(_) => {
+                    tracing::info!(
+                        timeout_millis = timeout.as_millis(),
+                        "Initial logical size timeout elapsed; starting background jobs"
+                    );
+                    Some(init_sizes_done)
+                }
+            };
 
             scopeguard::ScopeGuard::into_inner(guard);
 
-            // allow background jobs to start: we either completed prior stages, or they reached timeout
-            // and were skipped.  It is important that we do not let them block background jobs indefinitely,
-            // because things like consumption metrics for billing are blocked by this barrier.
+            // allow background jobs to start
             drop(background_jobs_can_start);
-            startup_checkpoint(
-                started_startup_at,
-                "background_jobs_can_start",
-                "Starting background jobs",
-            );
+            startup_checkpoint("background_jobs_can_start", "Starting background jobs");
 
-            // We are done. If we skipped any phases due to timeout, run them to completion here so that
-            // they will eventually update their startup_checkpoint, and so that we do not declare the
-            // 'complete' stage until all the other stages are really done.
-            let guard = scopeguard::guard_on_success((), |_| {
-                tracing::info!("Cancelled before waiting for skipped phases done")
-            });
-            if let Some(f) = init_remote_skipped {
-                f.await;
-            }
-            if let Some(f) = init_load_skipped {
-                f.await;
-            }
-            if let Some(f) = logical_sizes_skipped {
-                f.await;
-            }
-            scopeguard::ScopeGuard::into_inner(guard);
+            if let Some(init_sizes_done) = init_sizes_done {
+                // ending up here is not a bug; at the latest logical sizes will be queried by
+                // consumption metrics.
+                let guard = scopeguard::guard_on_success((), |_| tracing::info!("Cancelled before initial logical sizes completed"));
+                init_sizes_done.await;
 
-            startup_checkpoint(started_startup_at, "complete", "Startup complete");
+                scopeguard::ScopeGuard::into_inner(guard);
+
+                startup_checkpoint("initial_logical_sizes", "Initial logical sizes completed after timeout (background jobs already started)");
+
+            }
+
+            startup_checkpoint("complete", "Startup complete");
         };
 
         async move {
@@ -652,7 +574,6 @@ fn start_pageserver(
                     pageserver_listener,
                     conf.pg_auth_type,
                     libpq_ctx,
-                    task_mgr::shutdown_token(),
                 )
                 .await
             },

pageserver/src/config.rs

@@ -33,7 +33,8 @@ use crate::disk_usage_eviction_task::DiskUsageEvictionTaskConfig;
 use crate::tenant::config::TenantConf;
 use crate::tenant::config::TenantConfOpt;
 use crate::tenant::{
-    TENANTS_SEGMENT_NAME, TENANT_DELETED_MARKER_FILE_NAME, TIMELINES_SEGMENT_NAME,
+    TENANTS_SEGMENT_NAME, TENANT_ATTACHING_MARKER_FILENAME, TENANT_DELETED_MARKER_FILE_NAME,
+    TIMELINES_SEGMENT_NAME,
 };
 use crate::{
     IGNORED_TENANT_FILE_NAME, METADATA_FILE_NAME, TENANT_CONFIG_NAME, TENANT_LOCATION_CONFIG_NAME,
@@ -632,6 +633,11 @@ impl PageServerConf {
         self.tenants_path().join(tenant_id.to_string())
     }
 
+    pub fn tenant_attaching_mark_file_path(&self, tenant_id: &TenantId) -> Utf8PathBuf {
+        self.tenant_path(tenant_id)
+            .join(TENANT_ATTACHING_MARKER_FILENAME)
+    }
+
     pub fn tenant_ignore_mark_file_path(&self, tenant_id: &TenantId) -> Utf8PathBuf {
         self.tenant_path(tenant_id).join(IGNORED_TENANT_FILE_NAME)
     }

pageserver/src/consumption_metrics.rs

@@ -2,7 +2,6 @@
 //! and push them to a HTTP endpoint.
 use crate::context::{DownloadBehavior, RequestContext};
 use crate::task_mgr::{self, TaskKind, BACKGROUND_RUNTIME};
-use crate::tenant::tasks::BackgroundLoopKind;
 use crate::tenant::{mgr, LogicalSizeCalculationCause};
 use camino::Utf8PathBuf;
 use consumption_metrics::EventType;
@@ -11,7 +10,6 @@ use reqwest::Url;
 use std::collections::HashMap;
 use std::sync::Arc;
 use std::time::{Duration, SystemTime};
-use tokio::time::Instant;
 use tracing::*;
 use utils::id::NodeId;
 
@@ -89,12 +87,22 @@ pub async fn collect_metrics(
 
     let node_id = node_id.to_string();
 
+    // reminder: ticker is ready immediatedly
+    let mut ticker = tokio::time::interval(metric_collection_interval);
+
     loop {
-        let started_at = Instant::now();
+        let tick_at = tokio::select! {
+            _ = cancel.cancelled() => return Ok(()),
+            tick_at = ticker.tick() => tick_at,
+        };
 
         // these are point in time, with variable "now"
         let metrics = metrics::collect_all_metrics(&cached_metrics, &ctx).await;
 
+        if metrics.is_empty() {
+            continue;
+        }
+
         let metrics = Arc::new(metrics);
 
         // why not race cancellation here? because we are one of the last tasks, and if we are
@@ -133,19 +141,10 @@ pub async fn collect_metrics(
         let (_, _) = tokio::join!(flush, upload);
 
         crate::tenant::tasks::warn_when_period_overrun(
-            started_at.elapsed(),
+            tick_at.elapsed(),
             metric_collection_interval,
-            BackgroundLoopKind::ConsumptionMetricsCollectMetrics,
+            "consumption_metrics_collect_metrics",
         );
-
-        let res = tokio::time::timeout_at(
-            started_at + metric_collection_interval,
-            task_mgr::shutdown_token().cancelled(),
-        )
-        .await;
-        if res.is_ok() {
-            return Ok(());
-        }
     }
 }
 
@@ -244,14 +243,16 @@ async fn calculate_synthetic_size_worker(
     ctx: &RequestContext,
 ) -> anyhow::Result<()> {
     info!("starting calculate_synthetic_size_worker");
-    scopeguard::defer! {
-        info!("calculate_synthetic_size_worker stopped");
-    };
 
+    // reminder: ticker is ready immediatedly
+    let mut ticker = tokio::time::interval(synthetic_size_calculation_interval);
     let cause = LogicalSizeCalculationCause::ConsumptionMetricsSyntheticSize;
 
     loop {
-        let started_at = Instant::now();
+        let tick_at = tokio::select! {
+            _ = task_mgr::shutdown_watcher() => return Ok(()),
+            tick_at = ticker.tick() => tick_at,
+        };
 
         let tenants = match mgr::list_tenants().await {
             Ok(tenants) => tenants,
@@ -267,11 +268,6 @@ async fn calculate_synthetic_size_worker(
             }
 
             if let Ok(tenant) = mgr::get_tenant(tenant_id, true).await {
-                // TODO should we use concurrent_background_tasks_rate_limit() here, like the other background tasks?
-                // We can put in some prioritization for consumption metrics.
-                // Same for the loop that fetches computed metrics.
-                // By using the same limiter, we centralize metrics collection for "start" and "finished" counters,
-                // which turns out is really handy to understand the system.
                 if let Err(e) = tenant.calculate_synthetic_size(cause, ctx).await {
                     error!("failed to calculate synthetic size for tenant {tenant_id}: {e:#}");
                 }
@@ -279,18 +275,9 @@ async fn calculate_synthetic_size_worker(
         }
 
         crate::tenant::tasks::warn_when_period_overrun(
-            started_at.elapsed(),
+            tick_at.elapsed(),
             synthetic_size_calculation_interval,
-            BackgroundLoopKind::ConsumptionMetricsSyntheticSizeWorker,
+            "consumption_metrics_synthetic_size_worker",
         );
-
-        let res = tokio::time::timeout_at(
-            started_at + synthetic_size_calculation_interval,
-            task_mgr::shutdown_token().cancelled(),
-        )
-        .await;
-        if res.is_ok() {
-            return Ok(());
-        }
     }
 }

pageserver/src/control_plane_client.rs

@@ -57,10 +57,7 @@ impl ControlPlaneClient {
 
         if let Some(jwt) = &conf.control_plane_api_token {
             let mut headers = hyper::HeaderMap::new();
-            headers.insert(
-                "Authorization",
-                format!("Bearer {}", jwt.get_contents()).parse().unwrap(),
-            );
+            headers.insert("Authorization", jwt.get_contents().parse().unwrap());
             client = client.default_headers(headers);
         }
 
@@ -147,7 +144,7 @@ impl ControlPlaneGenerationsApi for ControlPlaneClient {
         Ok(response
             .tenants
             .into_iter()
-            .map(|t| (t.id, Generation::new(t.gen)))
+            .map(|t| (t.id, Generation::new(t.generation)))
             .collect::<HashMap<_, _>>())
     }
 

pageserver/src/deletion_queue.rs

@@ -10,7 +10,6 @@ use crate::control_plane_client::ControlPlaneGenerationsApi;
 use crate::metrics;
 use crate::tenant::remote_timeline_client::remote_layer_path;
 use crate::tenant::remote_timeline_client::remote_timeline_path;
-use crate::virtual_file::MaybeFatalIo;
 use crate::virtual_file::VirtualFile;
 use anyhow::Context;
 use camino::Utf8PathBuf;
@@ -272,9 +271,7 @@ impl DeletionHeader {
         let temp_path = path_with_suffix_extension(&header_path, TEMP_SUFFIX);
         VirtualFile::crashsafe_overwrite(&header_path, &temp_path, &header_bytes)
             .await
-            .maybe_fatal_err("save deletion header")?;
-
-        Ok(())
+            .map_err(Into::into)
     }
 }
 
@@ -363,7 +360,6 @@ impl DeletionList {
         let bytes = serde_json::to_vec(self).expect("Failed to serialize deletion list");
         VirtualFile::crashsafe_overwrite(&path, &temp_path, &bytes)
             .await
-            .maybe_fatal_err("save deletion list")
             .map_err(Into::into)
     }
 }
@@ -1302,6 +1298,10 @@ pub(crate) mod mock {
             }
         }
 
+        pub fn get_executed(&self) -> usize {
+            self.executed.load(Ordering::Relaxed)
+        }
+
         #[allow(clippy::await_holding_lock)]
         pub async fn pump(&self) {
             if let Some(remote_storage) = &self.remote_storage {

pageserver/src/deletion_queue/list_writer.rs

@@ -34,8 +34,6 @@ use crate::deletion_queue::TEMP_SUFFIX;
 use crate::metrics;
 use crate::tenant::remote_timeline_client::remote_layer_path;
 use crate::tenant::storage_layer::LayerFileName;
-use crate::virtual_file::on_fatal_io_error;
-use crate::virtual_file::MaybeFatalIo;
 
 // The number of keys in a DeletionList before we will proactively persist it
 // (without reaching a flush deadline).  This aims to deliver objects of the order
@@ -197,7 +195,7 @@ impl ListWriter {
                     debug!("Deletion header {header_path} not found, first start?");
                     Ok(None)
                 } else {
-                    on_fatal_io_error(&e, "reading deletion header");
+                    Err(anyhow::anyhow!(e))
                 }
             }
         }
@@ -218,9 +216,16 @@ impl ListWriter {
         self.pending.sequence = validated_sequence + 1;
 
         let deletion_directory = self.conf.deletion_prefix();
-        let mut dir = tokio::fs::read_dir(&deletion_directory)
-            .await
-            .fatal_err("read deletion directory");
+        let mut dir = match tokio::fs::read_dir(&deletion_directory).await {
+            Ok(d) => d,
+            Err(e) => {
+                warn!("Failed to open deletion list directory {deletion_directory}: {e:#}");
+
+                // Give up: if we can't read the deletion list directory, we probably can't
+                // write lists into it later, so the queue won't work.
+                return Err(e.into());
+            }
+        };
 
         let list_name_pattern =
             Regex::new("(?<sequence>[a-zA-Z0-9]{16})-(?<version>[a-zA-Z0-9]{2}).list").unwrap();
@@ -228,7 +233,7 @@ impl ListWriter {
         let temp_extension = format!(".{TEMP_SUFFIX}");
         let header_path = self.conf.deletion_header_path();
         let mut seqs: Vec<u64> = Vec::new();
-        while let Some(dentry) = dir.next_entry().await.fatal_err("read deletion dentry") {
+        while let Some(dentry) = dir.next_entry().await? {
             let file_name = dentry.file_name();
             let dentry_str = file_name.to_string_lossy();
 
@@ -241,9 +246,11 @@ impl ListWriter {
                 info!("Cleaning up temporary file {dentry_str}");
                 let absolute_path =
                     deletion_directory.join(dentry.file_name().to_str().expect("non-Unicode path"));
-                tokio::fs::remove_file(&absolute_path)
-                    .await
-                    .fatal_err("delete temp file");
+                if let Err(e) = tokio::fs::remove_file(&absolute_path).await {
+                    // Non-fatal error: we will just leave the file behind but not
+                    // try and load it.
+                    warn!("Failed to clean up temporary file {absolute_path}: {e:#}");
+                }
 
                 continue;
             }
@@ -283,9 +290,7 @@ impl ListWriter {
         for s in seqs {
             let list_path = self.conf.deletion_list_path(s);
 
-            let list_bytes = tokio::fs::read(&list_path)
-                .await
-                .fatal_err("read deletion list");
+            let list_bytes = tokio::fs::read(&list_path).await?;
 
             let mut deletion_list = match serde_json::from_slice::<DeletionList>(&list_bytes) {
                 Ok(l) => l,
@@ -344,7 +349,7 @@ impl ListWriter {
         info!("Started deletion frontend worker");
 
         // Synchronous, but we only do it once per process lifetime so it's tolerable
-        if let Err(e) = create_dir_all(self.conf.deletion_prefix()) {
+        if let Err(e) = create_dir_all(&self.conf.deletion_prefix()) {
             tracing::error!(
                 "Failed to create deletion list directory {}, deletions will not be executed ({e})",
                 self.conf.deletion_prefix(),

pageserver/src/deletion_queue/validator.rs

@@ -28,7 +28,6 @@ use crate::config::PageServerConf;
 use crate::control_plane_client::ControlPlaneGenerationsApi;
 use crate::control_plane_client::RetryForeverError;
 use crate::metrics;
-use crate::virtual_file::MaybeFatalIo;
 
 use super::deleter::DeleterMessage;
 use super::DeletionHeader;
@@ -288,9 +287,16 @@ where
     async fn cleanup_lists(&mut self, list_paths: Vec<Utf8PathBuf>) {
         for list_path in list_paths {
             debug!("Removing deletion list {list_path}");
-            tokio::fs::remove_file(&list_path)
-                .await
-                .fatal_err("remove deletion list");
+
+            if let Err(e) = tokio::fs::remove_file(&list_path).await {
+                // Unexpected: we should have permissions and nothing else should
+                // be touching these files.  We will leave the file behind.  Subsequent
+                // pageservers will try and load it again: hopefully whatever storage
+                // issue (probably permissions) has been fixed by then.
+                tracing::error!("Failed to delete {list_path}: {e:#}");
+                metrics::DELETION_QUEUE.unexpected_errors.inc();
+                break;
+            }
         }
     }
 

pageserver/src/disk_usage_eviction_task.rs

@@ -60,11 +60,7 @@ use utils::serde_percent::Percent;
 use crate::{
     config::PageServerConf,
     task_mgr::{self, TaskKind, BACKGROUND_RUNTIME},
-    tenant::{
-        self,
-        storage_layer::{AsLayerDesc, EvictionError, Layer},
-        Timeline,
-    },
+    tenant::{self, storage_layer::PersistentLayer, timeline::EvictionError, Timeline},
 };
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
@@ -112,7 +108,7 @@ pub fn launch_disk_usage_global_eviction_task(
                 _ = background_jobs_barrier.wait() => { }
             };
 
-            disk_usage_eviction_task(&state, task_config, &storage, &conf.tenants_path(), cancel)
+            disk_usage_eviction_task(&state, task_config, storage, &conf.tenants_path(), cancel)
                 .await;
             Ok(())
         },
@@ -125,7 +121,7 @@ pub fn launch_disk_usage_global_eviction_task(
 async fn disk_usage_eviction_task(
     state: &State,
     task_config: &DiskUsageEvictionTaskConfig,
-    _storage: &GenericRemoteStorage,
+    storage: GenericRemoteStorage,
     tenants_dir: &Utf8Path,
     cancel: CancellationToken,
 ) {
@@ -149,8 +145,14 @@ async fn disk_usage_eviction_task(
         let start = Instant::now();
 
         async {
-            let res =
-                disk_usage_eviction_task_iteration(state, task_config, tenants_dir, &cancel).await;
+            let res = disk_usage_eviction_task_iteration(
+                state,
+                task_config,
+                &storage,
+                tenants_dir,
+                &cancel,
+            )
+            .await;
 
             match res {
                 Ok(()) => {}
@@ -181,12 +183,13 @@ pub trait Usage: Clone + Copy + std::fmt::Debug {
 async fn disk_usage_eviction_task_iteration(
     state: &State,
     task_config: &DiskUsageEvictionTaskConfig,
+    storage: &GenericRemoteStorage,
     tenants_dir: &Utf8Path,
     cancel: &CancellationToken,
 ) -> anyhow::Result<()> {
     let usage_pre = filesystem_level_usage::get(tenants_dir, task_config)
         .context("get filesystem-level disk usage before evictions")?;
-    let res = disk_usage_eviction_task_iteration_impl(state, usage_pre, cancel).await;
+    let res = disk_usage_eviction_task_iteration_impl(state, storage, usage_pre, cancel).await;
     match res {
         Ok(outcome) => {
             debug!(?outcome, "disk_usage_eviction_iteration finished");
@@ -270,6 +273,7 @@ struct LayerCount {
 
 pub async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
     state: &State,
+    storage: &GenericRemoteStorage,
     usage_pre: U,
     cancel: &CancellationToken,
 ) -> anyhow::Result<IterationOutcome<U>> {
@@ -326,10 +330,9 @@ pub async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
     // If we get far enough in the list that we start to evict layers that are below
     // the tenant's min-resident-size threshold, print a warning, and memorize the disk
     // usage at that point, in 'usage_planned_min_resident_size_respecting'.
-    let mut batched: HashMap<_, Vec<_>> = HashMap::new();
+    let mut batched: HashMap<_, Vec<Arc<dyn PersistentLayer>>> = HashMap::new();
     let mut warned = None;
     let mut usage_planned = usage_pre;
-    let mut max_batch_size = 0;
     for (i, (partition, candidate)) in candidates.into_iter().enumerate() {
         if !usage_planned.has_pressure() {
             debug!(
@@ -346,18 +349,10 @@ pub async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
 
         usage_planned.add_available_bytes(candidate.layer.layer_desc().file_size);
 
-        // FIXME: batching makes no sense anymore because of no layermap locking, should just spawn
-        // tasks to evict all seen layers until we have evicted enough
-
-        let batch = batched.entry(TimelineKey(candidate.timeline)).or_default();
-
-        // semaphore will later be used to limit eviction concurrency, and we can express at
-        // most u32 number of permits. unlikely we would have u32::MAX layers to be evicted,
-        // but fail gracefully by not making batches larger.
-        if batch.len() < u32::MAX as usize {
-            batch.push(candidate.layer);
-            max_batch_size = max_batch_size.max(batch.len());
-        }
+        batched
+            .entry(TimelineKey(candidate.timeline))
+            .or_default()
+            .push(candidate.layer);
     }
 
     let usage_planned = match warned {
@@ -374,101 +369,64 @@ pub async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
 
     // phase2: evict victims batched by timeline
 
-    let mut js = tokio::task::JoinSet::new();
-
-    // ratelimit to 1k files or any higher max batch size
-    let limit = Arc::new(tokio::sync::Semaphore::new(1000.max(max_batch_size)));
-
+    // After the loop, `usage_assumed` is the post-eviction usage,
+    // according to internal accounting.
+    let mut usage_assumed = usage_pre;
+    let mut evictions_failed = LayerCount::default();
     for (timeline, batch) in batched {
         let tenant_id = timeline.tenant_id;
         let timeline_id = timeline.timeline_id;
-        let batch_size =
-            u32::try_from(batch.len()).expect("batch size limited to u32::MAX during partitioning");
-
-        // I dislike naming of `available_permits` but it means current total amount of permits
-        // because permits can be added
-        assert!(batch_size as usize <= limit.available_permits());
+        let batch_size = batch.len();
 
         debug!(%timeline_id, "evicting batch for timeline");
 
-        let evict = {
-            let limit = limit.clone();
-            let cancel = cancel.clone();
-            async move {
-                let mut evicted_bytes = 0;
-                let mut evictions_failed = LayerCount::default();
+        async {
+            let results = timeline.evict_layers(storage, &batch, cancel.clone()).await;
 
-                let Ok(_permit) = limit.acquire_many_owned(batch_size).await else {
-                    // semaphore closing means cancelled
-                    return (evicted_bytes, evictions_failed);
-                };
-
-                let results = timeline.evict_layers(&batch, &cancel).await;
-
-                match results {
-                    Ok(results) => {
-                        assert_eq!(results.len(), batch.len());
-                        for (result, layer) in results.into_iter().zip(batch.iter()) {
-                            let file_size = layer.layer_desc().file_size;
-                            match result {
-                                Some(Ok(())) => {
-                                    evicted_bytes += file_size;
-                                }
-                                Some(Err(EvictionError::NotFound | EvictionError::Downloaded)) => {
-                                    evictions_failed.file_sizes += file_size;
-                                    evictions_failed.count += 1;
-                                }
-                                None => {
-                                    assert!(cancel.is_cancelled());
-                                }
+            match results {
+                Err(e) => {
+                    warn!("failed to evict batch: {:#}", e);
+                }
+                Ok(results) => {
+                    assert_eq!(results.len(), batch.len());
+                    for (result, layer) in results.into_iter().zip(batch.iter()) {
+                        let file_size = layer.layer_desc().file_size;
+                        match result {
+                            Some(Ok(())) => {
+                                usage_assumed.add_available_bytes(file_size);
+                            }
+                            Some(Err(EvictionError::CannotEvictRemoteLayer)) => {
+                                unreachable!("get_local_layers_for_disk_usage_eviction finds only local layers")
+                            }
+                            Some(Err(EvictionError::FileNotFound)) => {
+                                evictions_failed.file_sizes += file_size;
+                                evictions_failed.count += 1;
+                            }
+                            Some(Err(
+                                e @ EvictionError::LayerNotFound(_)
+                                | e @ EvictionError::StatFailed(_),
+                            )) => {
+                                let e = utils::error::report_compact_sources(&e);
+                                warn!(%layer, "failed to evict layer: {e}");
+                                evictions_failed.file_sizes += file_size;
+                                evictions_failed.count += 1;
+                            }
+                            None => {
+                                assert!(cancel.is_cancelled());
+                                return;
                             }
                         }
                     }
-                    Err(e) => {
-                        warn!("failed to evict batch: {:#}", e);
-                    }
                 }
-                (evicted_bytes, evictions_failed)
             }
         }
-        .instrument(tracing::info_span!("evict_batch", %tenant_id, %timeline_id, batch_size));
+        .instrument(tracing::info_span!("evict_batch", %tenant_id, %timeline_id, batch_size))
+        .await;
 
-        js.spawn(evict);
-
-        // spwaning multiple thousands of these is essentially blocking, so give already spawned a
-        // chance of making progress
-        tokio::task::yield_now().await;
-    }
-
-    let join_all = async move {
-        // After the evictions, `usage_assumed` is the post-eviction usage,
-        // according to internal accounting.
-        let mut usage_assumed = usage_pre;
-        let mut evictions_failed = LayerCount::default();
-
-        while let Some(res) = js.join_next().await {
-            match res {
-                Ok((evicted_bytes, failed)) => {
-                    usage_assumed.add_available_bytes(evicted_bytes);
-                    evictions_failed.file_sizes += failed.file_sizes;
-                    evictions_failed.count += failed.count;
-                }
-                Err(je) if je.is_cancelled() => unreachable!("not used"),
-                Err(je) if je.is_panic() => { /* already logged */ }
-                Err(je) => tracing::error!("unknown JoinError: {je:?}"),
-            }
-        }
-        (usage_assumed, evictions_failed)
-    };
-
-    let (usage_assumed, evictions_failed) = tokio::select! {
-        tuple = join_all => { tuple },
-        _ = cancel.cancelled() => {
-            // close the semaphore to stop any pending acquires
-            limit.close();
+        if cancel.is_cancelled() {
             return Ok(IterationOutcome::Cancelled);
         }
-    };
+    }
 
     Ok(IterationOutcome::Finished(IterationOutcomeFinished {
         before: usage_pre,
@@ -483,7 +441,7 @@ pub async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
 #[derive(Clone)]
 struct EvictionCandidate {
     timeline: Arc<Timeline>,
-    layer: Layer,
+    layer: Arc<dyn PersistentLayer>,
     last_activity_ts: SystemTime,
 }
 

pageserver/src/http/openapi_spec.yml

@@ -306,67 +306,6 @@ paths:
               schema:
                 $ref: "#/components/schemas/ServiceUnavailableError"
 
-  /v1/tenant/{tenant_id}/timeline/{timeline_id}/get_timestamp_of_lsn:
-    parameters:
-      - name: tenant_id
-        in: path
-        required: true
-        schema:
-          type: string
-          format: hex
-      - name: timeline_id
-        in: path
-        required: true
-        schema:
-          type: string
-          format: hex
-    get:
-      description: Get timestamp for a given LSN
-      parameters:
-        - name: lsn
-          in: query
-          required: true
-          schema:
-            type: integer
-          description: A LSN to get the timestamp
-      responses:
-        "200":
-          description: OK
-          content:
-            application/json:
-              schema:
-                type: string
-                format: date-time
-        "400":
-          description: Error when no tenant id found in path, no timeline id or invalid timestamp
-          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"
-        "404":
-          description: Timeline not found, or there is no timestamp information for the given lsn
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/NotFoundError"
-        "500":
-          description: Generic operation error
-          content:
-            application/json:
-              schema:
-                $ref: "#/components/schemas/Error"
 
   /v1/tenant/{tenant_id}/timeline/{timeline_id}/get_lsn_by_timestamp:
     parameters:
@@ -392,19 +331,13 @@ paths:
             type: string
             format: date-time
           description: A timestamp to get the LSN
-        - name: version
-          in: query
-          required: false
-          schema:
-            type: integer
-          description: The version of the endpoint to use
       responses:
         "200":
           description: OK
           content:
             application/json:
               schema:
-                $ref: "#/components/schemas/LsnByTimestampResponse"
+                type: string
         "400":
           description: Error when no tenant id found in path, no timeline id or invalid timestamp
           content:
@@ -569,17 +502,7 @@ paths:
               schema:
                 $ref: "#/components/schemas/NotFoundError"
         "409":
-          description: |
-            The tenant is already known to Pageserver in some way,
-            and hence this `/attach` call has been rejected.
-
-            Some examples of how this can happen:
-            - tenant was created on this pageserver
-            - tenant attachment was started by an earlier call to `/attach`.
-
-            Callers should poll the tenant status's `attachment_status` field,
-            like for status 202. See the longer description for `POST /attach`
-            for details.
+          description: Tenant download is already in progress
           content:
             application/json:
               schema:
@@ -723,12 +646,6 @@ paths:
 
         Errors if the tenant is absent on disk, already present in memory or fails to schedule its load.
         Scheduling a load does not mean that the tenant would load successfully, check tenant status to ensure load correctness.
-      requestBody:
-        required: false
-        content:
-          application/json:
-            schema:
-              $ref: "#/components/schemas/TenantLoadRequest"
       responses:
         "202":
           description: Tenant scheduled to load successfully
@@ -1219,15 +1136,6 @@ components:
             new_tenant_id:
               type: string
               format: hex
-            generation:
-              type: integer
-              description: Attachment generation number.
-    TenantLoadRequest:
-      type: object
-      properties:
-        generation:
-          type: integer
-          description: Attachment generation number.
     TenantAttachRequest:
       type: object
       required:
@@ -1415,19 +1323,6 @@ components:
           type: string
           format: hex
 
-    LsnByTimestampResponse:
-      type: object
-      required:
-        - lsn
-        - kind
-      properties:
-        lsn:
-          type: string
-          format: hex
-        kind:
-          type: string
-          enum: [past, present, future, nodata]
-
     Error:
       type: object
       required:

pageserver/src/http/routes.rs

@@ -2,13 +2,11 @@
 //! Management HTTP API
 //!
 use std::collections::HashMap;
-use std::str::FromStr;
 use std::sync::Arc;
 
 use anyhow::{anyhow, Context, Result};
 use futures::TryFutureExt;
-use humantime::format_rfc3339;
-use hyper::header;
+use hyper::header::CONTENT_TYPE;
 use hyper::StatusCode;
 use hyper::{Body, Request, Response, Uri};
 use metrics::launch_timestamp::LaunchTimestamp;
@@ -17,7 +15,6 @@ use pageserver_api::models::{
     TenantLoadRequest, TenantLocationConfigRequest,
 };
 use remote_storage::GenericRemoteStorage;
-use serde_with::{serde_as, DisplayFromStr};
 use tenant_size_model::{SizeResult, StorageModel};
 use tokio_util::sync::CancellationToken;
 use tracing::*;
@@ -139,7 +136,9 @@ impl From<PageReconstructError> for ApiError {
             PageReconstructError::AncestorStopping(_) => {
                 ApiError::ResourceUnavailable(format!("{pre}").into())
             }
-            PageReconstructError::WalRedo(pre) => ApiError::InternalServerError(pre),
+            PageReconstructError::WalRedo(pre) => {
+                ApiError::InternalServerError(anyhow::Error::new(pre))
+            }
         }
     }
 }
@@ -485,8 +484,6 @@ async fn get_lsn_by_timestamp_handler(
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
-    let version: Option<u8> = parse_query_param(&request, "version")?;
-
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     let timestamp_raw = must_get_query_param(&request, "timestamp")?;
     let timestamp = humantime::parse_rfc3339(&timestamp_raw)
@@ -498,59 +495,13 @@ async fn get_lsn_by_timestamp_handler(
     let timeline = active_timeline_of_active_tenant(tenant_id, timeline_id).await?;
     let result = timeline.find_lsn_for_timestamp(timestamp_pg, &ctx).await?;
 
-    if version.unwrap_or(0) > 1 {
-        #[serde_as]
-        #[derive(serde::Serialize)]
-        struct Result {
-            #[serde_as(as = "DisplayFromStr")]
-            lsn: Lsn,
-            kind: &'static str,
-        }
-        let (lsn, kind) = match result {
-            LsnForTimestamp::Present(lsn) => (lsn, "present"),
-            LsnForTimestamp::Future(lsn) => (lsn, "future"),
-            LsnForTimestamp::Past(lsn) => (lsn, "past"),
-            LsnForTimestamp::NoData(lsn) => (lsn, "nodata"),
-        };
-        json_response(StatusCode::OK, Result { lsn, kind })
-    } else {
-        // FIXME: this is a temporary crutch not to break backwards compatibility
-        // See https://github.com/neondatabase/neon/pull/5608
-        let result = match result {
-            LsnForTimestamp::Present(lsn) => format!("{lsn}"),
-            LsnForTimestamp::Future(_lsn) => "future".into(),
-            LsnForTimestamp::Past(_lsn) => "past".into(),
-            LsnForTimestamp::NoData(_lsn) => "nodata".into(),
-        };
-        json_response(StatusCode::OK, result)
-    }
-}
-
-async fn get_timestamp_of_lsn_handler(
-    request: Request<Body>,
-    _cancel: CancellationToken,
-) -> Result<Response<Body>, ApiError> {
-    let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
-    check_permission(&request, Some(tenant_id))?;
-
-    let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
-
-    let lsn_str = must_get_query_param(&request, "lsn")?;
-    let lsn = Lsn::from_str(&lsn_str)
-        .with_context(|| format!("Invalid LSN: {lsn_str:?}"))
-        .map_err(ApiError::BadRequest)?;
-
-    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
-    let timeline = active_timeline_of_active_tenant(tenant_id, timeline_id).await?;
-    let result = timeline.get_timestamp_for_lsn(lsn, &ctx).await?;
-
-    match result {
-        Some(time) => {
-            let time = format_rfc3339(postgres_ffi::from_pg_timestamp(time)).to_string();
-            json_response(StatusCode::OK, time)
-        }
-        None => json_response(StatusCode::NOT_FOUND, ()),
-    }
+    let result = match result {
+        LsnForTimestamp::Present(lsn) => format!("{lsn}"),
+        LsnForTimestamp::Future(_lsn) => "future".into(),
+        LsnForTimestamp::Past(_lsn) => "past".into(),
+        LsnForTimestamp::NoData(_lsn) => "nodata".into(),
+    };
+    json_response(StatusCode::OK, result)
 }
 
 async fn tenant_attach_handler(
@@ -789,10 +740,6 @@ async fn tenant_size_handler(
         .map_err(ApiError::InternalServerError)?;
 
     let mut sizes = None;
-    let accepts_html = headers
-        .get(header::ACCEPT)
-        .map(|v| v == "text/html")
-        .unwrap_or_default();
     if !inputs_only.unwrap_or(false) {
         let storage_model = inputs
             .calculate_model()
@@ -800,11 +747,11 @@ async fn tenant_size_handler(
         let size = storage_model.calculate();
 
         // If request header expects html, return html
-        if accepts_html {
+        if headers["Accept"] == "text/html" {
             return synthetic_size_html_response(inputs, storage_model, size);
         }
         sizes = Some(size);
-    } else if accepts_html {
+    } else if headers["Accept"] == "text/html" {
         return Err(ApiError::BadRequest(anyhow!(
             "inputs_only parameter is incompatible with html output request"
         )));
@@ -955,7 +902,7 @@ fn synthetic_size_html_response(
 pub fn html_response(status: StatusCode, data: String) -> Result<Response<Body>, ApiError> {
     let response = Response::builder()
         .status(status)
-        .header(header::CONTENT_TYPE, "text/html")
+        .header(hyper::header::CONTENT_TYPE, "text/html")
         .body(Body::from(data.as_bytes().to_vec()))
         .map_err(|e| ApiError::InternalServerError(e.into()))?;
     Ok(response)
@@ -1089,17 +1036,9 @@ async fn put_tenant_location_config_handler(
     // The `Detached` state is special, it doesn't upsert a tenant, it removes
     // its local disk content and drops it from memory.
     if let LocationConfigMode::Detached = request_data.config.mode {
-        if let Err(e) = mgr::detach_tenant(conf, tenant_id, true, &state.deletion_queue_client)
+        mgr::detach_tenant(conf, tenant_id, true, &state.deletion_queue_client)
             .instrument(info_span!("tenant_detach", %tenant_id))
-            .await
-        {
-            match e {
-                TenantStateError::NotFound(_) => {
-                    // This API is idempotent: a NotFound on a detach is fine.
-                }
-                _ => return Err(e.into()),
-            }
-        }
+            .await?;
         return json_response(StatusCode::OK, ());
     }
 
@@ -1205,7 +1144,7 @@ async fn timeline_compact_handler(
         timeline
             .compact(&cancel, &ctx)
             .await
-            .map_err(|e| ApiError::InternalServerError(e.into()))?;
+            .map_err(ApiError::InternalServerError)?;
         json_response(StatusCode::OK, ())
     }
     .instrument(info_span!("manual_compaction", %tenant_id, %timeline_id))
@@ -1230,7 +1169,7 @@ async fn timeline_checkpoint_handler(
         timeline
             .compact(&cancel, &ctx)
             .await
-            .map_err(|e| ApiError::InternalServerError(e.into()))?;
+            .map_err(ApiError::InternalServerError)?;
 
         json_response(StatusCode::OK, ())
     }
@@ -1336,7 +1275,7 @@ async fn getpage_at_lsn_handler(
         Result::<_, ApiError>::Ok(
             Response::builder()
                 .status(StatusCode::OK)
-                .header(header::CONTENT_TYPE, "application/octet-stream")
+                .header(CONTENT_TYPE, "application/octet-stream")
                 .body(hyper::Body::from(page))
                 .unwrap(),
         )
@@ -1500,11 +1439,11 @@ async fn disk_usage_eviction_run(
 
     let state = get_state(&r);
 
-    if state.remote_storage.as_ref().is_none() {
+    let Some(storage) = state.remote_storage.clone() else {
         return Err(ApiError::InternalServerError(anyhow::anyhow!(
             "remote storage not configured, cannot run eviction iteration"
         )));
-    }
+    };
 
     let state = state.disk_usage_eviction_state.clone();
 
@@ -1522,6 +1461,7 @@ async fn disk_usage_eviction_run(
         async move {
             let res = crate::disk_usage_eviction_task::disk_usage_eviction_task_iteration_impl(
                 &state,
+                &storage,
                 usage,
                 &child_cancel,
             )
@@ -1734,10 +1674,6 @@ pub fn make_router(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/get_lsn_by_timestamp",
             |r| api_handler(r, get_lsn_by_timestamp_handler),
         )
-        .get(
-            "/v1/tenant/:tenant_id/timeline/:timeline_id/get_timestamp_of_lsn",
-            |r| api_handler(r, get_timestamp_of_lsn_handler),
-        )
         .put("/v1/tenant/:tenant_id/timeline/:timeline_id/do_gc", |r| {
             api_handler(r, timeline_gc_handler)
         })

pageserver/src/lib.rs

@@ -149,10 +149,6 @@ fn ends_with_suffix(path: &Utf8Path, suffix: &str) -> bool {
     }
 }
 
-// FIXME: DO NOT ADD new query methods like this, which will have a next step of parsing timelineid
-// from the directory name. Instead create type "UninitMark(TimelineId)" and only parse it once
-// from the name.
-
 pub fn is_uninit_mark(path: &Utf8Path) -> bool {
     ends_with_suffix(path, TIMELINE_UNINIT_MARK_SUFFIX)
 }
@@ -177,9 +173,6 @@ fn is_walkdir_io_not_found(e: &walkdir::Error) -> bool {
 /// delaying is needed.
 #[derive(Clone)]
 pub struct InitializationOrder {
-    /// Each initial tenant load task carries this until it is done loading timelines from remote storage
-    pub initial_tenant_load_remote: Option<utils::completion::Completion>,
-
     /// Each initial tenant load task carries this until completion.
     pub initial_tenant_load: Option<utils::completion::Completion>,
 

pageserver/src/metrics.rs

@@ -1067,26 +1067,6 @@ pub(crate) static TENANT_TASK_EVENTS: Lazy<IntCounterVec> = Lazy::new(|| {
     .expect("Failed to register tenant_task_events metric")
 });
 
-pub(crate) static BACKGROUND_LOOP_SEMAPHORE_WAIT_START_COUNT: Lazy<IntCounterVec> =
-    Lazy::new(|| {
-        register_int_counter_vec!(
-            "pageserver_background_loop_semaphore_wait_start_count",
-            "Counter for background loop concurrency-limiting semaphore acquire calls started",
-            &["task"],
-        )
-        .unwrap()
-    });
-
-pub(crate) static BACKGROUND_LOOP_SEMAPHORE_WAIT_FINISH_COUNT: Lazy<IntCounterVec> =
-    Lazy::new(|| {
-        register_int_counter_vec!(
-            "pageserver_background_loop_semaphore_wait_finish_count",
-            "Counter for background loop concurrency-limiting semaphore acquire calls finished",
-            &["task"],
-        )
-        .unwrap()
-    });
-
 pub(crate) static BACKGROUND_LOOP_PERIOD_OVERRUN_COUNT: Lazy<IntCounterVec> = Lazy::new(|| {
     register_int_counter_vec!(
         "pageserver_background_loop_period_overrun_count",
@@ -1388,23 +1368,28 @@ impl TimelineMetrics {
         }
     }
 
-    pub(crate) fn record_new_file_metrics(&self, sz: u64) {
+    pub fn record_new_file_metrics(&self, sz: u64) {
         self.resident_physical_size_add(sz);
         self.num_persistent_files_created.inc_by(1);
         self.persistent_bytes_written.inc_by(sz);
     }
 
-    pub(crate) fn resident_physical_size_sub(&self, sz: u64) {
+    pub fn resident_physical_size_sub(&self, sz: u64) {
         self.resident_physical_size_gauge.sub(sz);
         crate::metrics::RESIDENT_PHYSICAL_SIZE_GLOBAL.sub(sz);
     }
 
-    pub(crate) fn resident_physical_size_add(&self, sz: u64) {
+    pub fn resident_physical_size_add(&self, sz: u64) {
         self.resident_physical_size_gauge.add(sz);
         crate::metrics::RESIDENT_PHYSICAL_SIZE_GLOBAL.add(sz);
     }
 
-    pub(crate) fn resident_physical_size_get(&self) -> u64 {
+    pub fn resident_physical_size_set(&self, sz: u64) {
+        self.resident_physical_size_gauge.set(sz);
+        crate::metrics::RESIDENT_PHYSICAL_SIZE_GLOBAL.set(sz);
+    }
+
+    pub fn resident_physical_size_get(&self) -> u64 {
         self.resident_physical_size_gauge.get()
     }
 }

pageserver/src/page_cache.rs

@@ -318,6 +318,15 @@ impl std::ops::Deref for PageWriteGuard<'_> {
     }
 }
 
+impl AsMut<[u8; PAGE_SZ]> for PageWriteGuard<'_> {
+    fn as_mut(&mut self) -> &mut [u8; PAGE_SZ] {
+        match &mut self.state {
+            PageWriteGuardState::Invalid { inner, _permit } => inner.buf,
+            PageWriteGuardState::Downgraded => unreachable!(),
+        }
+    }
+}
+
 impl<'a> PageWriteGuard<'a> {
     /// Mark that the buffer contents are now valid.
     #[must_use]

pageserver/src/page_service.rs

@@ -122,7 +122,6 @@ pub async fn libpq_listener_main(
     listener: TcpListener,
     auth_type: AuthType,
     listener_ctx: RequestContext,
-    cancel: CancellationToken,
 ) -> anyhow::Result<()> {
     listener.set_nonblocking(true)?;
     let tokio_listener = tokio::net::TcpListener::from_std(listener)?;
@@ -131,7 +130,7 @@ pub async fn libpq_listener_main(
     while let Some(res) = tokio::select! {
         biased;
 
-        _ = cancel.cancelled() => {
+        _ = task_mgr::shutdown_watcher() => {
             // We were requested to shut down.
             None
         }
@@ -300,7 +299,7 @@ impl PageServerHandler {
                 Ok(flush_r?)
             },
             _ = self.cancel.cancelled() => {
-                Err(QueryError::Shutdown)
+                Err(QueryError::Other(anyhow::anyhow!("Shutting down")))
             }
         )
     }
@@ -317,11 +316,11 @@ impl PageServerHandler {
                 let msg = tokio::select! {
                     biased;
 
-                    _ = self.cancel.cancelled() => {
+                    _ = task_mgr::shutdown_watcher() => {
                         // We were requested to shut down.
                         let msg = "pageserver is shutting down";
                         let _ = pgb.write_message_noflush(&BeMessage::ErrorResponse(msg, None));
-                        Err(QueryError::Shutdown)
+                        Err(QueryError::Other(anyhow::anyhow!(msg)))
                     }
 
                     msg = pgb.read_message() => { msg.map_err(QueryError::from)}
@@ -415,10 +414,10 @@ impl PageServerHandler {
             let msg = tokio::select! {
                 biased;
 
-                _ = self.cancel.cancelled() => {
+                _ = task_mgr::shutdown_watcher() => {
                     // We were requested to shut down.
                     info!("shutdown request received in page handler");
-                    return Err(QueryError::Shutdown)
+                    break;
                 }
 
                 msg = pgb.read_message() => { msg }

pageserver/src/pgdatadir_mapping.rs

@@ -19,7 +19,6 @@ use postgres_ffi::BLCKSZ;
 use postgres_ffi::{Oid, TimestampTz, TransactionId};
 use serde::{Deserialize, Serialize};
 use std::collections::{hash_map, HashMap, HashSet};
-use std::ops::ControlFlow;
 use std::ops::Range;
 use tokio_util::sync::CancellationToken;
 use tracing::{debug, trace, warn};
@@ -371,6 +370,7 @@ impl Timeline {
         }
     }
 
+    ///
     /// Subroutine of find_lsn_for_timestamp(). Returns true, if there are any
     /// commits that committed after 'search_timestamp', at LSN 'probe_lsn'.
     ///
@@ -385,50 +385,6 @@ impl Timeline {
         found_larger: &mut bool,
         ctx: &RequestContext,
     ) -> Result<bool, PageReconstructError> {
-        self.map_all_timestamps(probe_lsn, ctx, |timestamp| {
-            if timestamp >= search_timestamp {
-                *found_larger = true;
-                return ControlFlow::Break(true);
-            } else {
-                *found_smaller = true;
-            }
-            ControlFlow::Continue(())
-        })
-        .await
-    }
-
-    /// Obtain the possible timestamp range for the given lsn.
-    ///
-    /// If the lsn has no timestamps, returns None. returns `(min, max, median)` if it has timestamps.
-    pub async fn get_timestamp_for_lsn(
-        &self,
-        probe_lsn: Lsn,
-        ctx: &RequestContext,
-    ) -> Result<Option<TimestampTz>, PageReconstructError> {
-        let mut max: Option<TimestampTz> = None;
-        self.map_all_timestamps(probe_lsn, ctx, |timestamp| {
-            if let Some(max_prev) = max {
-                max = Some(max_prev.max(timestamp));
-            } else {
-                max = Some(timestamp);
-            }
-            ControlFlow::Continue(())
-        })
-        .await?;
-
-        Ok(max)
-    }
-
-    /// Runs the given function on all the timestamps for a given lsn
-    ///
-    /// The return value is either given by the closure, or set to the `Default`
-    /// impl's output.
-    async fn map_all_timestamps<T: Default>(
-        &self,
-        probe_lsn: Lsn,
-        ctx: &RequestContext,
-        mut f: impl FnMut(TimestampTz) -> ControlFlow<T>,
-    ) -> Result<T, PageReconstructError> {
         for segno in self
             .list_slru_segments(SlruKind::Clog, probe_lsn, ctx)
             .await?
@@ -446,14 +402,16 @@ impl Timeline {
                     timestamp_bytes.copy_from_slice(&clog_page[BLCKSZ as usize..]);
                     let timestamp = TimestampTz::from_be_bytes(timestamp_bytes);
 
-                    match f(timestamp) {
-                        ControlFlow::Break(b) => return Ok(b),
-                        ControlFlow::Continue(()) => (),
+                    if timestamp >= search_timestamp {
+                        *found_larger = true;
+                        return Ok(true);
+                    } else {
+                        *found_smaller = true;
                     }
                 }
             }
         }
-        Ok(Default::default())
+        Ok(false)
     }
 
     /// Get a list of SLRU segments
@@ -541,24 +499,6 @@ impl Timeline {
         self.get(CHECKPOINT_KEY, lsn, ctx).await
     }
 
-    pub async fn list_aux_files(
-        &self,
-        lsn: Lsn,
-        ctx: &RequestContext,
-    ) -> Result<HashMap<String, Bytes>, PageReconstructError> {
-        match self.get(AUX_FILES_KEY, lsn, ctx).await {
-            Ok(buf) => match AuxFilesDirectory::des(&buf).context("deserialization failure") {
-                Ok(dir) => Ok(dir.files),
-                Err(e) => Err(PageReconstructError::from(e)),
-            },
-            Err(e) => {
-                // This is expected: historical databases do not have the key.
-                debug!("Failed to get info about AUX files: {}", e);
-                Ok(HashMap::new())
-            }
-        }
-    }
-
     /// Does the same as get_current_logical_size but counted on demand.
     /// Used to initialize the logical size tracking on startup.
     ///
@@ -676,9 +616,7 @@ impl Timeline {
 
         result.add_key(CONTROLFILE_KEY);
         result.add_key(CHECKPOINT_KEY);
-        if self.get(AUX_FILES_KEY, lsn, ctx).await.is_ok() {
-            result.add_key(AUX_FILES_KEY);
-        }
+
         Ok(result.to_keyspace())
     }
 
@@ -754,12 +692,6 @@ impl<'a> DatadirModification<'a> {
         })?;
         self.put(DBDIR_KEY, Value::Image(buf.into()));
 
-        // Create AuxFilesDirectory
-        let buf = AuxFilesDirectory::ser(&AuxFilesDirectory {
-            files: HashMap::new(),
-        })?;
-        self.put(AUX_FILES_KEY, Value::Image(Bytes::from(buf)));
-
         let buf = TwoPhaseDirectory::ser(&TwoPhaseDirectory {
             xids: HashSet::new(),
         })?;
@@ -864,12 +796,6 @@ impl<'a> DatadirModification<'a> {
             // 'true', now write the updated 'dbdirs' map back.
             let buf = DbDirectory::ser(&dbdir)?;
             self.put(DBDIR_KEY, Value::Image(buf.into()));
-
-            // Create AuxFilesDirectory as well
-            let buf = AuxFilesDirectory::ser(&AuxFilesDirectory {
-                files: HashMap::new(),
-            })?;
-            self.put(AUX_FILES_KEY, Value::Image(Bytes::from(buf)));
         }
         if r.is_none() {
             // Create RelDirectory
@@ -1194,37 +1120,6 @@ impl<'a> DatadirModification<'a> {
         Ok(())
     }
 
-    pub async fn put_file(
-        &mut self,
-        path: &str,
-        content: &[u8],
-        ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
-        let mut dir = match self.get(AUX_FILES_KEY, ctx).await {
-            Ok(buf) => AuxFilesDirectory::des(&buf)?,
-            Err(e) => {
-                // This is expected: historical databases do not have the key.
-                debug!("Failed to get info about AUX files: {}", e);
-                AuxFilesDirectory {
-                    files: HashMap::new(),
-                }
-            }
-        };
-        let path = path.to_string();
-        if content.is_empty() {
-            dir.files.remove(&path);
-        } else {
-            dir.files.insert(path, Bytes::copy_from_slice(content));
-        }
-        self.put(
-            AUX_FILES_KEY,
-            Value::Image(Bytes::from(
-                AuxFilesDirectory::ser(&dir).context("serialize")?,
-            )),
-        );
-        Ok(())
-    }
-
     ///
     /// Flush changes accumulated so far to the underlying repository.
     ///
@@ -1360,11 +1255,6 @@ struct RelDirectory {
     rels: HashSet<(Oid, u8)>,
 }
 
-#[derive(Debug, Serialize, Deserialize, Default)]
-struct AuxFilesDirectory {
-    files: HashMap<String, Bytes>,
-}
-
 #[derive(Debug, Serialize, Deserialize)]
 struct RelSizeEntry {
     nblocks: u32,
@@ -1413,12 +1303,10 @@ static ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; BLCKSZ as usize]);
 // 02 pg_twophase
 //
 // 03 misc
-//    Controlfile
+//    controlfile
 //    checkpoint
 //    pg_version
 //
-// 04 aux files
-//
 // Below is a full list of the keyspace allocation:
 //
 // DbDir:
@@ -1456,11 +1344,6 @@ static ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; BLCKSZ as usize]);
 //
 // Checkpoint:
 // 03 00000000 00000000 00000000 00   00000001
-//
-// AuxFiles:
-// 03 00000000 00000000 00000000 00   00000002
-//
-
 //-- Section 01: relation data and metadata
 
 const DBDIR_KEY: Key = Key {
@@ -1684,15 +1567,6 @@ const CHECKPOINT_KEY: Key = Key {
     field6: 1,
 };
 
-const AUX_FILES_KEY: Key = Key {
-    field1: 0x03,
-    field2: 0,
-    field3: 0,
-    field4: 0,
-    field5: 0,
-    field6: 2,
-};
-
 // Reverse mappings for a few Keys.
 // These are needed by WAL redo manager.
 

pageserver/src/tenant/delete.rs

@@ -3,10 +3,10 @@ use std::sync::Arc;
 use anyhow::Context;
 use camino::{Utf8Path, Utf8PathBuf};
 use pageserver_api::models::TenantState;
-use remote_storage::{GenericRemoteStorage, RemotePath};
+use remote_storage::{DownloadError, GenericRemoteStorage, RemotePath};
 use tokio::sync::OwnedMutexGuard;
 use tokio_util::sync::CancellationToken;
-use tracing::{error, instrument, warn, Instrument, Span};
+use tracing::{error, info, instrument, warn, Instrument, Span};
 
 use utils::{
     backoff, completion, crashsafe, fs_ext,
@@ -25,9 +25,11 @@ use super::{
     remote_timeline_client::{FAILED_REMOTE_OP_RETRIES, FAILED_UPLOAD_WARN_THRESHOLD},
     span,
     timeline::delete::DeleteTimelineFlow,
-    tree_sort_timelines, DeleteTimelineError, Tenant, TenantPreload,
+    tree_sort_timelines, DeleteTimelineError, Tenant,
 };
 
+const SHOULD_RESUME_DELETION_FETCH_MARK_ATTEMPTS: u32 = 3;
+
 #[derive(Debug, thiserror::Error)]
 pub(crate) enum DeleteTenantError {
     #[error("GetTenant {0}")]
@@ -58,7 +60,7 @@ fn remote_tenant_delete_mark_path(
         .context("Failed to strip workdir prefix")
         .and_then(RemotePath::new)
         .context("tenant path")?;
-    Ok(tenant_remote_path.join(Utf8Path::new("timelines/deleted")))
+    Ok(tenant_remote_path.join(Utf8Path::new("deleted")))
 }
 
 async fn create_remote_delete_mark(
@@ -148,8 +150,7 @@ async fn ensure_timelines_dir_empty(timelines_path: &Utf8Path) -> Result<(), Del
     // Assert timelines dir is empty.
     if !fs_ext::is_directory_empty(timelines_path).await? {
         // Display first 10 items in directory
-        let list = fs_ext::list_dir(timelines_path).await.context("list_dir")?;
-        let list = &list.into_iter().take(10).collect::<Vec<_>>();
+        let list = &fs_ext::list_dir(timelines_path).await.context("list_dir")?[..10];
         return Err(DeleteTenantError::Other(anyhow::anyhow!(
             "Timelines directory is not empty after all timelines deletion: {list:?}"
         )));
@@ -238,6 +239,32 @@ async fn cleanup_remaining_fs_traces(
     Ok(())
 }
 
+pub(crate) async fn remote_delete_mark_exists(
+    conf: &PageServerConf,
+    tenant_id: &TenantId,
+    remote_storage: &GenericRemoteStorage,
+) -> anyhow::Result<bool> {
+    // If remote storage is there we rely on it
+    let remote_mark_path = remote_tenant_delete_mark_path(conf, tenant_id).context("path")?;
+
+    let result = backoff::retry(
+        || async { remote_storage.download(&remote_mark_path).await },
+        |e| matches!(e, DownloadError::NotFound),
+        SHOULD_RESUME_DELETION_FETCH_MARK_ATTEMPTS,
+        SHOULD_RESUME_DELETION_FETCH_MARK_ATTEMPTS,
+        "fetch_tenant_deletion_mark",
+        // TODO: use a cancellation token (https://github.com/neondatabase/neon/issues/5066)
+        backoff::Cancel::new(CancellationToken::new(), || unreachable!()),
+    )
+    .await;
+
+    match result {
+        Ok(_) => Ok(true),
+        Err(DownloadError::NotFound) => Ok(false),
+        Err(e) => Err(anyhow::anyhow!(e)).context("remote_delete_mark_exists")?,
+    }
+}
+
 /// Orchestrates tenant shut down of all tasks, removes its in-memory structures,
 /// and deletes its data from both disk and s3.
 /// The sequence of steps:
@@ -249,9 +276,10 @@ async fn cleanup_remaining_fs_traces(
 /// 6. Remove remote mark
 /// 7. Cleanup remaining fs traces, tenant dir, config, timelines dir, local delete mark
 /// It is resumable from any step in case a crash/restart occurs.
-/// There are two entrypoints to the process:
+/// There are three entrypoints to the process:
 /// 1. [`DeleteTenantFlow::run`] this is the main one called by a management api handler.
-/// 2. [`DeleteTenantFlow::resume_from_attach`] is called when deletion is resumed tenant is found to be deleted during attach process.
+/// 2. [`DeleteTenantFlow::resume_from_load`] is called during restarts when local or remote deletion marks are still there.
+/// 3. [`DeleteTenantFlow::resume_from_attach`] is called when deletion is resumed tenant is found to be deleted during attach process.
 ///  Note the only other place that messes around timeline delete mark is the `Tenant::spawn_load` function.
 #[derive(Default)]
 pub enum DeleteTenantFlow {
@@ -350,7 +378,7 @@ impl DeleteTenantFlow {
 
     pub(crate) async fn should_resume_deletion(
         conf: &'static PageServerConf,
-        remote_mark_exists: bool,
+        remote_storage: Option<&GenericRemoteStorage>,
         tenant: &Tenant,
     ) -> Result<Option<DeletionGuard>, DeleteTenantError> {
         let acquire = |t: &Tenant| {
@@ -361,25 +389,66 @@ impl DeleteTenantFlow {
             )
         };
 
-        if remote_mark_exists {
-            return Ok(acquire(tenant));
-        }
-
         let tenant_id = tenant.tenant_id;
         // Check local mark first, if its there there is no need to go to s3 to check whether remote one exists.
         if conf.tenant_deleted_mark_file_path(&tenant_id).exists() {
+            return Ok(acquire(tenant));
+        }
+
+        let remote_storage = match remote_storage {
+            Some(remote_storage) => remote_storage,
+            None => return Ok(None),
+        };
+
+        if remote_delete_mark_exists(conf, &tenant_id, remote_storage).await? {
             Ok(acquire(tenant))
         } else {
             Ok(None)
         }
     }
 
+    pub(crate) async fn resume_from_load(
+        guard: DeletionGuard,
+        tenant: &Arc<Tenant>,
+        init_order: Option<&InitializationOrder>,
+        tenants: &'static tokio::sync::RwLock<TenantsMap>,
+        ctx: &RequestContext,
+    ) -> Result<(), DeleteTenantError> {
+        let (_, progress) = completion::channel();
+
+        tenant
+            .set_stopping(progress, true, false)
+            .await
+            .expect("cant be stopping or broken");
+
+        // Do not consume valuable resources during the load phase, continue deletion once init phase is complete.
+        let background_jobs_can_start = init_order.as_ref().map(|x| &x.background_jobs_can_start);
+        if let Some(background) = background_jobs_can_start {
+            info!("waiting for backgound jobs barrier");
+            background.clone().wait().await;
+            info!("ready for backgound jobs barrier");
+        }
+
+        // Tenant may not be loadable if we fail late in cleanup_remaining_fs_traces (e g remove timelines dir)
+        let timelines_path = tenant.conf.timelines_path(&tenant.tenant_id);
+        if timelines_path.exists() {
+            tenant.load(init_order, ctx).await.context("load")?;
+        }
+
+        Self::background(
+            guard,
+            tenant.conf,
+            tenant.remote_storage.clone(),
+            tenants,
+            tenant,
+        )
+        .await
+    }
+
     pub(crate) async fn resume_from_attach(
         guard: DeletionGuard,
         tenant: &Arc<Tenant>,
-        preload: Option<TenantPreload>,
         tenants: &'static tokio::sync::RwLock<TenantsMap>,
-        init_order: Option<InitializationOrder>,
         ctx: &RequestContext,
     ) -> Result<(), DeleteTenantError> {
         let (_, progress) = completion::channel();
@@ -389,10 +458,7 @@ impl DeleteTenantFlow {
             .await
             .expect("cant be stopping or broken");
 
-        tenant
-            .attach(init_order, preload, ctx)
-            .await
-            .context("attach")?;
+        tenant.attach(ctx).await.context("attach")?;
 
         Self::background(
             guard,

pageserver/src/tenant/ephemeral_file.rs

@@ -354,7 +354,8 @@ mod tests {
         }
 
         // Test a large blob that spans multiple pages
-        let mut large_data = vec![0; 20000];
+        let mut large_data = Vec::new();
+        large_data.resize(20000, 0);
         thread_rng().fill_bytes(&mut large_data);
         let pos_large = file.write_blob(&large_data, &ctx).await?;
         let result = file.block_cursor().read_blob(pos_large, &ctx).await?;

pageserver/src/tenant/layer_map.rs

@@ -639,10 +639,147 @@ impl LayerMap {
         }
 
         println!("historic_layers:");
-        for desc in self.iter_historic_layers() {
-            desc.dump();
+        for layer in self.iter_historic_layers() {
+            layer.dump(verbose, ctx)?;
         }
         println!("End dump LayerMap");
         Ok(())
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::LayerMap;
+    use crate::tenant::storage_layer::LayerFileName;
+    use std::str::FromStr;
+    use std::sync::Arc;
+
+    mod l0_delta_layers_updated {
+
+        use crate::tenant::{
+            storage_layer::{AsLayerDesc, PersistentLayerDesc},
+            timeline::layer_manager::LayerFileManager,
+        };
+
+        use super::*;
+
+        struct LayerObject(PersistentLayerDesc);
+
+        impl AsLayerDesc for LayerObject {
+            fn layer_desc(&self) -> &PersistentLayerDesc {
+                &self.0
+            }
+        }
+
+        impl LayerObject {
+            fn new(desc: PersistentLayerDesc) -> Self {
+                LayerObject(desc)
+            }
+        }
+
+        type TestLayerFileManager = LayerFileManager<LayerObject>;
+
+        #[test]
+        fn for_full_range_delta() {
+            // l0_delta_layers are used by compaction, and should observe all buffered updates
+            l0_delta_layers_updated_scenario(
+                 "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__0000000053423C21-0000000053424D69",
+                 true
+             )
+        }
+
+        #[test]
+        fn for_non_full_range_delta() {
+            // has minimal uncovered areas compared to l0_delta_layers_updated_on_insert_replace_remove_for_full_range_delta
+            l0_delta_layers_updated_scenario(
+                 "000000000000000000000000000000000001-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFE__0000000053423C21-0000000053424D69",
+                 // because not full range
+                 false
+             )
+        }
+
+        #[test]
+        fn for_image() {
+            l0_delta_layers_updated_scenario(
+                 "000000000000000000000000000000000000-000000000000000000000000000000010000__0000000053424D69",
+                 // code only checks if it is a full range layer, doesn't care about images, which must
+                 // mean we should in practice never have full range images
+                 false
+             )
+        }
+
+        #[test]
+        fn replacing_missing_l0_is_notfound() {
+            // original impl had an oversight, and L0 was an anyhow::Error. anyhow::Error should
+            // however only happen for precondition failures.
+
+            let layer = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__0000000053423C21-0000000053424D69";
+            let layer = LayerFileName::from_str(layer).unwrap();
+            let layer = PersistentLayerDesc::from(layer);
+
+            // same skeletan construction; see scenario below
+            let not_found = Arc::new(LayerObject::new(layer.clone()));
+            let new_version = Arc::new(LayerObject::new(layer));
+
+            // after the immutable storage state refactor, the replace operation
+            // will not use layer map any more. We keep it here for consistency in test cases
+            // and can remove it in the future.
+            let _map = LayerMap::default();
+
+            let mut mapping = TestLayerFileManager::new();
+
+            mapping
+                .replace_and_verify(not_found, new_version)
+                .unwrap_err();
+        }
+
+        fn l0_delta_layers_updated_scenario(layer_name: &str, expected_l0: bool) {
+            let name = LayerFileName::from_str(layer_name).unwrap();
+            let skeleton = PersistentLayerDesc::from(name);
+
+            let remote = Arc::new(LayerObject::new(skeleton.clone()));
+            let downloaded = Arc::new(LayerObject::new(skeleton));
+
+            let mut map = LayerMap::default();
+            let mut mapping = LayerFileManager::new();
+
+            // two disjoint Arcs in different lifecycle phases. even if it seems they must be the
+            // same layer, we use LayerMap::compare_arced_layers as the identity of layers.
+            assert_eq!(remote.layer_desc(), downloaded.layer_desc());
+
+            let expected_in_counts = (1, usize::from(expected_l0));
+
+            map.batch_update()
+                .insert_historic(remote.layer_desc().clone());
+            mapping.insert(remote.clone());
+            assert_eq!(
+                count_layer_in(&map, remote.layer_desc()),
+                expected_in_counts
+            );
+
+            mapping
+                .replace_and_verify(remote, downloaded.clone())
+                .expect("name derived attributes are the same");
+            assert_eq!(
+                count_layer_in(&map, downloaded.layer_desc()),
+                expected_in_counts
+            );
+
+            map.batch_update().remove_historic(downloaded.layer_desc());
+            assert_eq!(count_layer_in(&map, downloaded.layer_desc()), (0, 0));
+        }
+
+        fn count_layer_in(map: &LayerMap, layer: &PersistentLayerDesc) -> (usize, usize) {
+            let historic = map
+                .iter_historic_layers()
+                .filter(|x| x.key() == layer.key())
+                .count();
+            let l0s = map
+                .get_level0_deltas()
+                .expect("why does this return a result");
+            let l0 = l0s.iter().filter(|x| x.key() == layer.key()).count();
+
+            (historic, l0)
+        }
+    }
+}

pageserver/src/tenant/mgr.rs

@@ -1,7 +1,7 @@
 //! This module acts as a switchboard to access different repositories managed by this
 //! page server.
 
-use camino::{Utf8DirEntry, Utf8Path, Utf8PathBuf};
+use camino::{Utf8Path, Utf8PathBuf};
 use rand::{distributions::Alphanumeric, Rng};
 use std::collections::{hash_map, HashMap};
 use std::sync::Arc;
@@ -26,7 +26,9 @@ use crate::deletion_queue::DeletionQueueClient;
 use crate::task_mgr::{self, TaskKind};
 use crate::tenant::config::{AttachmentMode, LocationConf, LocationMode, TenantConfOpt};
 use crate::tenant::delete::DeleteTenantFlow;
-use crate::tenant::{create_tenant_files, AttachedTenantConf, SpawnMode, Tenant, TenantState};
+use crate::tenant::{
+    create_tenant_files, AttachedTenantConf, CreateTenantFilesMode, Tenant, TenantState,
+};
 use crate::{InitializationOrder, IGNORED_TENANT_FILE_NAME, TEMP_FILE_SUFFIX};
 
 use utils::crashsafe::path_with_suffix_extension;
@@ -149,49 +151,6 @@ async fn safe_rename_tenant_dir(path: impl AsRef<Utf8Path>) -> std::io::Result<U
 
 static TENANTS: Lazy<RwLock<TenantsMap>> = Lazy::new(|| RwLock::new(TenantsMap::Initializing));
 
-/// Create a directory, including parents.  This does no fsyncs and makes
-/// no guarantees about the persistence of the resulting metadata: for
-/// use when creating dirs for use as cache.
-async fn unsafe_create_dir_all(path: &Utf8PathBuf) -> std::io::Result<()> {
-    let mut dirs_to_create = Vec::new();
-    let mut path: &Utf8Path = path.as_ref();
-
-    // Figure out which directories we need to create.
-    loop {
-        let meta = tokio::fs::metadata(path).await;
-        match meta {
-            Ok(metadata) if metadata.is_dir() => break,
-            Ok(_) => {
-                return Err(std::io::Error::new(
-                    std::io::ErrorKind::AlreadyExists,
-                    format!("non-directory found in path: {path}"),
-                ));
-            }
-            Err(ref e) if e.kind() == std::io::ErrorKind::NotFound => {}
-            Err(e) => return Err(e),
-        }
-
-        dirs_to_create.push(path);
-
-        match path.parent() {
-            Some(parent) => path = parent,
-            None => {
-                return Err(std::io::Error::new(
-                    std::io::ErrorKind::InvalidInput,
-                    format!("can't find parent of path '{path}'"),
-                ));
-            }
-        }
-    }
-
-    // Create directories from parent to child.
-    for &path in dirs_to_create.iter().rev() {
-        tokio::fs::create_dir(path).await?;
-    }
-
-    Ok(())
-}
-
 fn emergency_generations(
     tenant_confs: &HashMap<TenantId, anyhow::Result<LocationConf>>,
 ) -> HashMap<TenantId, Generation> {
@@ -253,99 +212,83 @@ async fn init_load_generations(
     Ok(Some(generations))
 }
 
-/// Given a directory discovered in the pageserver's tenants/ directory, attempt
-/// to load a tenant config from it.
-///
-/// If file is missing, return Ok(None)
-fn load_tenant_config(
-    conf: &'static PageServerConf,
-    dentry: Utf8DirEntry,
-) -> anyhow::Result<Option<(TenantId, anyhow::Result<LocationConf>)>> {
-    let tenant_dir_path = dentry.path().to_path_buf();
-    if crate::is_temporary(&tenant_dir_path) {
-        info!("Found temporary tenant directory, removing: {tenant_dir_path}");
-        // No need to use safe_remove_tenant_dir_all because this is already
-        // a temporary path
-        if let Err(e) = std::fs::remove_dir_all(&tenant_dir_path) {
-            error!(
-                "Failed to remove temporary directory '{}': {:?}",
-                tenant_dir_path, e
-            );
-        }
-        return Ok(None);
-    }
-
-    // This case happens if we crash during attachment before writing a config into the dir
-    let is_empty = tenant_dir_path
-        .is_empty_dir()
-        .with_context(|| format!("Failed to check whether {tenant_dir_path:?} is an empty dir"))?;
-    if is_empty {
-        info!("removing empty tenant directory {tenant_dir_path:?}");
-        if let Err(e) = std::fs::remove_dir(&tenant_dir_path) {
-            error!(
-                "Failed to remove empty tenant directory '{}': {e:#}",
-                tenant_dir_path
-            )
-        }
-        return Ok(None);
-    }
-
-    let tenant_ignore_mark_file = tenant_dir_path.join(IGNORED_TENANT_FILE_NAME);
-    if tenant_ignore_mark_file.exists() {
-        info!("Found an ignore mark file {tenant_ignore_mark_file:?}, skipping the tenant");
-        return Ok(None);
-    }
-
-    let tenant_id = match tenant_dir_path
-        .file_name()
-        .unwrap_or_default()
-        .parse::<TenantId>()
-    {
-        Ok(id) => id,
-        Err(_) => {
-            warn!("Invalid tenant path (garbage in our repo directory?): {tenant_dir_path}",);
-            return Ok(None);
-        }
-    };
-
-    Ok(Some((
-        tenant_id,
-        Tenant::load_tenant_config(conf, &tenant_id),
-    )))
-}
-
 /// Initial stage of load: walk the local tenants directory, clean up any temp files,
 /// and load configurations for the tenants we found.
-///
-/// Do this in parallel, because we expect 10k+ tenants, so serial execution can take
-/// seconds even on reasonably fast drives.
 async fn init_load_tenant_configs(
     conf: &'static PageServerConf,
 ) -> anyhow::Result<HashMap<TenantId, anyhow::Result<LocationConf>>> {
     let tenants_dir = conf.tenants_path();
 
-    let dentries = tokio::task::spawn_blocking(move || -> anyhow::Result<Vec<Utf8DirEntry>> {
-        let dir_entries = tenants_dir
-            .read_dir_utf8()
-            .with_context(|| format!("Failed to list tenants dir {tenants_dir:?}"))?;
-
-        Ok(dir_entries.collect::<Result<Vec<_>, std::io::Error>>()?)
-    })
-    .await??;
+    let mut dir_entries = tenants_dir
+        .read_dir_utf8()
+        .with_context(|| format!("Failed to list tenants dir {tenants_dir:?}"))?;
 
     let mut configs = HashMap::new();
 
-    let mut join_set = JoinSet::new();
-    for dentry in dentries {
-        join_set.spawn_blocking(move || load_tenant_config(conf, dentry));
-    }
+    loop {
+        match dir_entries.next() {
+            None => break,
+            Some(Ok(dentry)) => {
+                let tenant_dir_path = dentry.path().to_path_buf();
+                if crate::is_temporary(&tenant_dir_path) {
+                    info!("Found temporary tenant directory, removing: {tenant_dir_path}");
+                    // No need to use safe_remove_tenant_dir_all because this is already
+                    // a temporary path
+                    if let Err(e) = fs::remove_dir_all(&tenant_dir_path).await {
+                        error!(
+                            "Failed to remove temporary directory '{}': {:?}",
+                            tenant_dir_path, e
+                        );
+                    }
+                    continue;
+                }
 
-    while let Some(r) = join_set.join_next().await {
-        if let Some((tenant_id, tenant_config)) = r?? {
-            configs.insert(tenant_id, tenant_config);
+                // This case happens if we:
+                // * crash during attach before creating the attach marker file
+                // * crash during tenant delete before removing tenant directory
+                let is_empty = tenant_dir_path.is_empty_dir().with_context(|| {
+                    format!("Failed to check whether {tenant_dir_path:?} is an empty dir")
+                })?;
+                if is_empty {
+                    info!("removing empty tenant directory {tenant_dir_path:?}");
+                    if let Err(e) = fs::remove_dir(&tenant_dir_path).await {
+                        error!(
+                            "Failed to remove empty tenant directory '{}': {e:#}",
+                            tenant_dir_path
+                        )
+                    }
+                    continue;
+                }
+
+                let tenant_ignore_mark_file = tenant_dir_path.join(IGNORED_TENANT_FILE_NAME);
+                if tenant_ignore_mark_file.exists() {
+                    info!("Found an ignore mark file {tenant_ignore_mark_file:?}, skipping the tenant");
+                    continue;
+                }
+
+                let tenant_id = match tenant_dir_path
+                    .file_name()
+                    .unwrap_or_default()
+                    .parse::<TenantId>()
+                {
+                    Ok(id) => id,
+                    Err(_) => {
+                        warn!(
+                            "Invalid tenant path (garbage in our repo directory?): {tenant_dir_path}",
+                        );
+                        continue;
+                    }
+                };
+
+                configs.insert(tenant_id, Tenant::load_tenant_config(conf, &tenant_id));
+            }
+            Some(Err(e)) => {
+                // An error listing the top level directory indicates serious problem
+                // with local filesystem: we will fail to load, and fail to start.
+                anyhow::bail!(e);
+            }
         }
     }
-
     Ok(configs)
 }
 
@@ -434,15 +377,14 @@ pub async fn init_tenant_mgr(
         location_conf.attach_in_generation(generation);
         Tenant::persist_tenant_config(conf, &tenant_id, &location_conf).await?;
 
-        match tenant_spawn(
+        match schedule_local_tenant_processing(
             conf,
             tenant_id,
             &tenant_dir_path,
-            resources.clone(),
             AttachedTenantConf::try_from(location_conf)?,
+            resources.clone(),
             Some(init_order.clone()),
             &TENANTS,
-            SpawnMode::Normal,
             &ctx,
         ) {
             Ok(tenant) => {
@@ -462,18 +404,15 @@ pub async fn init_tenant_mgr(
     Ok(())
 }
 
-/// Wrapper for Tenant::spawn that checks invariants before running, and inserts
-/// a broken tenant in the map if Tenant::spawn fails.
 #[allow(clippy::too_many_arguments)]
-pub(crate) fn tenant_spawn(
+pub(crate) fn schedule_local_tenant_processing(
     conf: &'static PageServerConf,
     tenant_id: TenantId,
     tenant_path: &Utf8Path,
-    resources: TenantSharedResources,
     location_conf: AttachedTenantConf,
+    resources: TenantSharedResources,
     init_order: Option<InitializationOrder>,
     tenants: &'static tokio::sync::RwLock<TenantsMap>,
-    mode: SpawnMode,
     ctx: &RequestContext,
 ) -> anyhow::Result<Arc<Tenant>> {
     anyhow::ensure!(
@@ -497,24 +436,37 @@ pub(crate) fn tenant_spawn(
         "Cannot load tenant, ignore mark found at {tenant_ignore_mark:?}"
     );
 
-    info!("Attaching tenant {tenant_id}");
-    let tenant = match Tenant::spawn(
-        conf,
-        tenant_id,
-        resources,
-        location_conf,
-        init_order,
-        tenants,
-        mode,
-        ctx,
-    ) {
-        Ok(tenant) => tenant,
-        Err(e) => {
-            error!("Failed to spawn tenant {tenant_id}, reason: {e:#}");
-            Tenant::create_broken_tenant(conf, tenant_id, format!("{e:#}"))
+    let tenant = if conf.tenant_attaching_mark_file_path(&tenant_id).exists() {
+        info!("tenant {tenant_id} has attaching mark file, resuming its attach operation");
+        if resources.remote_storage.is_none() {
+            warn!("tenant {tenant_id} has attaching mark file, but pageserver has no remote storage configured");
+            Tenant::create_broken_tenant(
+                conf,
+                tenant_id,
+                "attaching mark file present but no remote storage configured".to_string(),
+            )
+        } else {
+            match Tenant::spawn_attach(conf, tenant_id, resources, location_conf, tenants, ctx) {
+                Ok(tenant) => tenant,
+                Err(e) => {
+                    error!("Failed to spawn_attach tenant {tenant_id}, reason: {e:#}");
+                    Tenant::create_broken_tenant(conf, tenant_id, format!("{e:#}"))
+                }
+            }
         }
+    } else {
+        info!("tenant {tenant_id} is assumed to be loadable, starting load operation");
+        // Start loading the tenant into memory. It will initially be in Loading state.
+        Tenant::spawn_load(
+            conf,
+            tenant_id,
+            location_conf,
+            resources,
+            init_order,
+            tenants,
+            ctx,
+        )
     };
-
     Ok(tenant)
 }
 
@@ -650,41 +602,29 @@ pub(crate) async fn create_tenant(
     ctx: &RequestContext,
 ) -> Result<Arc<Tenant>, TenantMapInsertError> {
     tenant_map_insert(tenant_id, || async {
+
         let location_conf = LocationConf::attached_single(tenant_conf, generation);
 
         // We're holding the tenants lock in write mode while doing local IO.
         // If this section ever becomes contentious, introduce a new `TenantState::Creating`
         // and do the work in that state.
-        super::create_tenant_files(conf, &location_conf, &tenant_id).await?;
-
+        let tenant_directory = super::create_tenant_files(conf, &location_conf, &tenant_id, CreateTenantFilesMode::Create).await?;
         // TODO: tenant directory remains on disk if we bail out from here on.
         //       See https://github.com/neondatabase/neon/issues/4233
 
-        let tenant_path = conf.tenant_path(&tenant_id);
-
-        let created_tenant = tenant_spawn(
-            conf,
-            tenant_id,
-            &tenant_path,
-            resources,
-            AttachedTenantConf::try_from(location_conf)?,
-            None,
-            &TENANTS,
-            SpawnMode::Create,
-            ctx,
-        )?;
+        let created_tenant =
+            schedule_local_tenant_processing(conf, tenant_id, &tenant_directory,
+                AttachedTenantConf::try_from(location_conf)?, resources, None, &TENANTS, ctx)?;
         // TODO: tenant object & its background loops remain, untracked in tenant map, if we fail here.
         //      See https://github.com/neondatabase/neon/issues/4233
 
         let crated_tenant_id = created_tenant.tenant_id();
         anyhow::ensure!(
-            tenant_id == crated_tenant_id,
-            "loaded created tenant has unexpected tenant id \
-                (expect {tenant_id} != actual {crated_tenant_id})",
-        );
+                tenant_id == crated_tenant_id,
+                "loaded created tenant has unexpected tenant id (expect {tenant_id} != actual {crated_tenant_id})",
+            );
         Ok(created_tenant)
-    })
-    .await
+    }).await
 }
 
 #[derive(Debug, thiserror::Error)]
@@ -715,7 +655,7 @@ pub(crate) async fn set_new_tenant_config(
     Ok(())
 }
 
-#[instrument(skip_all, fields(%tenant_id))]
+#[instrument(skip_all, fields(tenant_id, new_location_config))]
 pub(crate) async fn upsert_location(
     conf: &'static PageServerConf,
     tenant_id: TenantId,
@@ -793,56 +733,37 @@ pub(crate) async fn upsert_location(
                 }
             }
 
-            let tenant_path = conf.tenant_path(&tenant_id);
-
             let new_slot = match &new_location_config.mode {
-                LocationMode::Secondary(_) => {
-                    // Directory doesn't need to be fsync'd because if we crash it can
-                    // safely be recreated next time this tenant location is configured.
-                    unsafe_create_dir_all(&tenant_path)
-                        .await
-                        .with_context(|| format!("Creating {tenant_path}"))?;
-
-                    Tenant::persist_tenant_config(conf, &tenant_id, &new_location_config)
-                        .await
-                        .map_err(SetNewTenantConfigError::Persist)?;
-
-                    TenantSlot::Secondary
-                }
+                LocationMode::Secondary(_) => TenantSlot::Secondary,
                 LocationMode::Attached(_attach_config) => {
+                    // Do a schedule_local_tenant_processing
                     // FIXME: should avoid doing this disk I/O inside the TenantsMap lock,
                     // we have the same problem in load_tenant/attach_tenant.  Probably
                     // need a lock in TenantSlot to fix this.
-                    let timelines_path = conf.timelines_path(&tenant_id);
-
-                    // Directory doesn't need to be fsync'd because we do not depend on
-                    // it to exist after crashes: it may be recreated when tenant is
-                    // re-attached, see https://github.com/neondatabase/neon/issues/5550
-                    unsafe_create_dir_all(&timelines_path)
-                        .await
-                        .with_context(|| format!("Creating {timelines_path}"))?;
-
                     Tenant::persist_tenant_config(conf, &tenant_id, &new_location_config)
                         .await
                         .map_err(SetNewTenantConfigError::Persist)?;
-
-                    let tenant = tenant_spawn(
+                    let tenant_path = conf.tenant_path(&tenant_id);
+                    let resources = TenantSharedResources {
+                        broker_client,
+                        remote_storage,
+                        deletion_queue_client,
+                    };
+                    let new_tenant = schedule_local_tenant_processing(
                         conf,
                         tenant_id,
                         &tenant_path,
-                        TenantSharedResources {
-                            broker_client,
-                            remote_storage,
-                            deletion_queue_client,
-                        },
                         AttachedTenantConf::try_from(new_location_config)?,
+                        resources,
                         None,
                         &TENANTS,
-                        SpawnMode::Normal,
                         ctx,
-                    )?;
+                    )
+                    .with_context(|| {
+                        format!("Failed to schedule tenant processing in path {tenant_path:?}")
+                    })?;
 
-                    TenantSlot::Attached(tenant)
+                    TenantSlot::Attached(new_tenant)
                 }
             };
 
@@ -850,6 +771,7 @@ pub(crate) async fn upsert_location(
         })
         .await?;
     }
+
     Ok(())
 }
 
@@ -1029,7 +951,7 @@ pub(crate) async fn load_tenant(
         location_conf.attach_in_generation(generation);
         Tenant::persist_tenant_config(conf, &tenant_id, &location_conf).await?;
 
-        let new_tenant = tenant_spawn(conf, tenant_id, &tenant_path, resources, AttachedTenantConf::try_from(location_conf)?, None,  &TENANTS, SpawnMode::Normal, ctx)
+        let new_tenant = schedule_local_tenant_processing(conf, tenant_id, &tenant_path, AttachedTenantConf::try_from(location_conf)?, resources, None,  &TENANTS, ctx)
             .with_context(|| {
                 format!("Failed to schedule tenant processing in path {tenant_path:?}")
             })?;
@@ -1103,12 +1025,18 @@ pub(crate) async fn attach_tenant(
 ) -> Result<(), TenantMapInsertError> {
     tenant_map_insert(tenant_id, || async {
         let location_conf = LocationConf::attached_single(tenant_conf, generation);
-        let tenant_dir = create_tenant_files(conf, &location_conf, &tenant_id).await?;
+        let tenant_dir = create_tenant_files(conf, &location_conf, &tenant_id, CreateTenantFilesMode::Attach).await?;
         // TODO: tenant directory remains on disk if we bail out from here on.
         //       See https://github.com/neondatabase/neon/issues/4233
 
-        let attached_tenant = tenant_spawn(conf, tenant_id, &tenant_dir,
-            resources, AttachedTenantConf::try_from(location_conf)?, None, &TENANTS, SpawnMode::Normal, ctx)?;
+        // Without the attach marker, schedule_local_tenant_processing will treat the attached tenant as fully attached
+        let marker_file_exists = conf
+            .tenant_attaching_mark_file_path(&tenant_id)
+            .try_exists()
+            .context("check for attach marker file existence")?;
+        anyhow::ensure!(marker_file_exists, "create_tenant_files should have created the attach marker file");
+
+        let attached_tenant = schedule_local_tenant_processing(conf, tenant_id, &tenant_dir, AttachedTenantConf::try_from(location_conf)?, resources, None, &TENANTS, ctx)?;
         // TODO: tenant object & its background loops remain, untracked in tenant map, if we fail here.
         //      See https://github.com/neondatabase/neon/issues/4233
 

pageserver/src/tenant/par_fsync.rs

@@ -57,7 +57,8 @@ pub fn par_fsync(paths: &[Utf8PathBuf]) -> io::Result<()> {
     fsync_in_thread_pool(paths)
 }
 
-/// Parallel fsync asynchronously.
+/// Parallel fsync asynchronously. If number of files are less than PARALLEL_PATH_THRESHOLD, fsync is done in the current
+/// execution thread. Otherwise, we will spawn_blocking and run it in tokio.
 pub async fn par_fsync_async(paths: &[Utf8PathBuf]) -> io::Result<()> {
     const MAX_CONCURRENT_FSYNC: usize = 64;
     let mut next = paths.iter().peekable();

pageserver/src/tenant/remote_timeline_client.rs

@@ -167,15 +167,39 @@
 //!   - download their remote [`IndexPart`]s
 //!   - create `Timeline` struct and a `RemoteTimelineClient`
 //!   - initialize the client's upload queue with its `IndexPart`
+//!   - create [`RemoteLayer`](super::storage_layer::RemoteLayer) instances
+//!     for layers that are referenced by `IndexPart` but not present locally
 //!   - schedule uploads for layers that are only present locally.
+//!   - if the remote `IndexPart`'s metadata was newer than the metadata in
+//!     the local filesystem, write the remote metadata to the local filesystem
 //! - After the above is done for each timeline, open the tenant for business by
 //!   transitioning it from `TenantState::Attaching` to `TenantState::Active` state.
 //!   This starts the timelines' WAL-receivers and the tenant's GC & Compaction loops.
 //!
+//! We keep track of the fact that a client is in `Attaching` state in a marker
+//! file on the local disk. This is critical because, when we restart the pageserver,
+//! we do not want to do the `List timelines` step for each tenant that has already
+//! been successfully attached (for performance & cost reasons).
+//! Instead, for a tenant without the attach marker file, we assume that the
+//! local state is in sync or ahead of the remote state. This includes the list
+//! of all of the tenant's timelines, which is particularly critical to be up-to-date:
+//! if there's a timeline on the remote that the pageserver doesn't know about,
+//! the GC will not consider its branch point, leading to data loss.
+//! So, for a tenant with the attach marker file, we know that we do not yet have
+//! persisted all the remote timeline's metadata files locally. To exclude the
+//! risk above, we re-run the procedure for such tenants
+//!
 //! # Operating Without Remote Storage
 //!
 //! If no remote storage configuration is provided, the [`RemoteTimelineClient`] is
 //! not created and the uploads are skipped.
+//! Theoretically, it should be ok to remove and re-add remote storage configuration to
+//! the pageserver config at any time, since it doesn't make a difference to
+//! [`Timeline::load_layer_map`].
+//! Of course, the remote timeline dir must not change while we have de-configured
+//! remote storage, i.e., the pageserver must remain the owner of the given prefix
+//! in remote storage.
+//! But note that we don't test any of this right now.
 //!
 //! [`Tenant::timeline_init_and_sync`]: super::Tenant::timeline_init_and_sync
 //! [`Timeline::load_layer_map`]: super::Timeline::load_layer_map
@@ -187,7 +211,8 @@ mod upload;
 use anyhow::Context;
 use camino::Utf8Path;
 use chrono::{NaiveDateTime, Utc};
-
+// re-export these
+pub use download::{is_temp_download_file, list_remote_timelines};
 use scopeguard::ScopeGuard;
 use tokio_util::sync::CancellationToken;
 use utils::backoff::{
@@ -212,7 +237,7 @@ use crate::metrics::{
 };
 use crate::task_mgr::shutdown_token;
 use crate::tenant::debug_assert_current_span_has_tenant_and_timeline_id;
-use crate::tenant::storage_layer::AsLayerDesc;
+use crate::tenant::remote_timeline_client::index::LayerFileMetadata;
 use crate::tenant::upload_queue::Delete;
 use crate::tenant::TIMELINES_SEGMENT_NAME;
 use crate::{
@@ -230,13 +255,10 @@ use utils::id::{TenantId, TimelineId};
 
 use self::index::IndexPart;
 
-use super::storage_layer::{Layer, LayerFileName, ResidentLayer};
+use super::storage_layer::LayerFileName;
 use super::upload_queue::SetDeletedFlagProgress;
 use super::Generation;
 
-pub(crate) use download::{is_temp_download_file, list_remote_timelines};
-pub(crate) use index::LayerFileMetadata;
-
 // Occasional network issues and such can cause remote operations to fail, and
 // that's expected. If a download fails, we log it at info-level, and retry.
 // But after FAILED_DOWNLOAD_WARN_THRESHOLD retries, we start to log it at WARN
@@ -446,10 +468,7 @@ impl RemoteTimelineClient {
     //
 
     /// Download index file
-    pub async fn download_index_file(
-        &self,
-        cancel: CancellationToken,
-    ) -> Result<MaybeDeletedIndexPart, DownloadError> {
+    pub async fn download_index_file(&self) -> Result<MaybeDeletedIndexPart, DownloadError> {
         let _unfinished_gauge_guard = self.metrics.call_begin(
             &RemoteOpFileKind::Index,
             &RemoteOpKind::Download,
@@ -463,7 +482,6 @@ impl RemoteTimelineClient {
             &self.tenant_id,
             &self.timeline_id,
             self.generation,
-            cancel,
         )
         .measure_remote_op(
             self.tenant_id,
@@ -609,203 +627,101 @@ impl RemoteTimelineClient {
     ///
     /// Launch an upload operation in the background.
     ///
-    pub(crate) fn schedule_layer_file_upload(
+    pub fn schedule_layer_file_upload(
         self: &Arc<Self>,
-        layer: ResidentLayer,
+        layer_file_name: &LayerFileName,
+        layer_metadata: &LayerFileMetadata,
     ) -> anyhow::Result<()> {
         let mut guard = self.upload_queue.lock().unwrap();
         let upload_queue = guard.initialized_mut()?;
 
-        self.schedule_layer_file_upload0(upload_queue, layer);
-        self.launch_queued_tasks(upload_queue);
-        Ok(())
-    }
-
-    fn schedule_layer_file_upload0(
-        self: &Arc<Self>,
-        upload_queue: &mut UploadQueueInitialized,
-        layer: ResidentLayer,
-    ) {
-        let metadata = layer.metadata();
-
         upload_queue
             .latest_files
-            .insert(layer.layer_desc().filename(), metadata.clone());
+            .insert(layer_file_name.clone(), layer_metadata.clone());
         upload_queue.latest_files_changes_since_metadata_upload_scheduled += 1;
 
-        info!("scheduled layer file upload {layer}");
-        let op = UploadOp::UploadLayer(layer, metadata);
+        let op = UploadOp::UploadLayer(layer_file_name.clone(), layer_metadata.clone());
         self.calls_unfinished_metric_begin(&op);
         upload_queue.queued_operations.push_back(op);
+
+        info!("scheduled layer file upload {layer_file_name}");
+
+        // Launch the task immediately, if possible
+        self.launch_queued_tasks(upload_queue);
+        Ok(())
     }
 
     /// Launch a delete operation in the background.
     ///
-    /// The operation does not modify local filesystem state.
+    /// The operation does not modify local state but assumes the local files have already been
+    /// deleted, and is used to mirror those changes to remote.
     ///
     /// Note: This schedules an index file upload before the deletions.  The
-    /// deletion won't actually be performed, until all previously scheduled
+    /// deletion won't actually be performed, until any previously scheduled
     /// upload operations, and the index file upload, have completed
     /// successfully.
     pub fn schedule_layer_file_deletion(
         self: &Arc<Self>,
-        names: &[LayerFileName],
+        names: Vec<LayerFileName>,
     ) -> anyhow::Result<()> {
         let mut guard = self.upload_queue.lock().unwrap();
         let upload_queue = guard.initialized_mut()?;
 
-        let with_generations =
-            self.schedule_unlinking_of_layers_from_index_part0(upload_queue, names.iter().cloned());
-
-        self.schedule_deletion_of_unlinked0(upload_queue, with_generations);
-
-        // Launch the tasks immediately, if possible
-        self.launch_queued_tasks(upload_queue);
-        Ok(())
-    }
-
-    /// Unlinks the layer files from `index_part.json` but does not yet schedule deletion for the
-    /// layer files, leaving them dangling.
-    ///
-    /// The files will be leaked in remote storage unless [`Self::schedule_deletion_of_unlinked`]
-    /// is invoked on them.
-    pub(crate) fn schedule_gc_update(self: &Arc<Self>, gc_layers: &[Layer]) -> anyhow::Result<()> {
-        let mut guard = self.upload_queue.lock().unwrap();
-        let upload_queue = guard.initialized_mut()?;
-
-        // just forget the return value; after uploading the next index_part.json, we can consider
-        // the layer files as "dangling". this is fine, at worst case we create work for the
-        // scrubber.
-
-        let names = gc_layers.iter().map(|x| x.layer_desc().filename());
-
-        self.schedule_unlinking_of_layers_from_index_part0(upload_queue, names);
-
-        self.launch_queued_tasks(upload_queue);
-
-        Ok(())
-    }
-
-    /// Update the remote index file, removing the to-be-deleted files from the index,
-    /// allowing scheduling of actual deletions later.
-    fn schedule_unlinking_of_layers_from_index_part0<I>(
-        self: &Arc<Self>,
-        upload_queue: &mut UploadQueueInitialized,
-        names: I,
-    ) -> Vec<(LayerFileName, Generation)>
-    where
-        I: IntoIterator<Item = LayerFileName>,
-    {
         // Deleting layers doesn't affect the values stored in TimelineMetadata,
         // so we don't need update it. Just serialize it.
         let metadata = upload_queue.latest_metadata.clone();
 
-        // Decorate our list of names with each name's generation, dropping
-        // names that are unexpectedly missing from our metadata.
-        let with_generations: Vec<_> = names
-            .into_iter()
-            .filter_map(|name| {
-                let meta = upload_queue.latest_files.remove(&name);
+        // Update the remote index file, removing the to-be-deleted files from the index,
+        // before deleting the actual files.
+        //
+        // Once we start removing files from upload_queue.latest_files, there's
+        // no going back! Otherwise, some of the files would already be removed
+        // from latest_files, but not yet scheduled for deletion. Use a closure
+        // to syntactically forbid ? or bail! calls here.
+        let no_bail_here = || {
+            // Decorate our list of names with each name's generation, dropping
+            // makes that are unexpectedly missing from our metadata.
+            let with_generations: Vec<_> = names
+                .into_iter()
+                .filter_map(|name| {
+                    // Remove from latest_files, learning the file's remote generation in the process
+                    let meta = upload_queue.latest_files.remove(&name);
 
-                if let Some(meta) = meta {
-                    upload_queue.latest_files_changes_since_metadata_upload_scheduled += 1;
-                    Some((name, meta.generation))
-                } else {
-                    // This can only happen if we forgot to to schedule the file upload
-                    // before scheduling the delete. Log it because it is a rare/strange
-                    // situation, and in case something is misbehaving, we'd like to know which
-                    // layers experienced this.
-                    info!("Deleting layer {name} not found in latest_files list, never uploaded?");
-                    None
-                }
-            })
-            .collect();
+                    if let Some(meta) = meta {
+                        upload_queue.latest_files_changes_since_metadata_upload_scheduled += 1;
+                        Some((name, meta.generation))
+                    } else {
+                        // This can only happen if we forgot to to schedule the file upload
+                        // before scheduling the delete. Log it because it is a rare/strange
+                        // situation, and in case something is misbehaving, we'd like to know which
+                        // layers experienced this.
+                        info!(
+                            "Deleting layer {name} not found in latest_files list, never uploaded?"
+                        );
+                        None
+                    }
+                })
+                .collect();
 
-        #[cfg(feature = "testing")]
-        for (name, gen) in &with_generations {
-            if let Some(unexpected) = upload_queue.dangling_files.insert(name.to_owned(), *gen) {
-                if &unexpected == gen {
-                    tracing::error!("{name} was unlinked twice with same generation");
-                } else {
-                    tracing::error!("{name} was unlinked twice with different generations {gen:?} and {unexpected:?}");
-                }
+            if upload_queue.latest_files_changes_since_metadata_upload_scheduled > 0 {
+                self.schedule_index_upload(upload_queue, metadata);
             }
-        }
 
-        // after unlinking files from the upload_queue.latest_files we must always schedule an
-        // index_part update, because that needs to be uploaded before we can actually delete the
-        // files.
-        if upload_queue.latest_files_changes_since_metadata_upload_scheduled > 0 {
-            self.schedule_index_upload(upload_queue, metadata);
-        }
-
-        with_generations
-    }
-
-    /// Schedules deletion for layer files which have previously been unlinked from the
-    /// `index_part.json` with [`Self::schedule_gc_update`] or [`Self::schedule_compaction_update`].
-    pub(crate) fn schedule_deletion_of_unlinked(
-        self: &Arc<Self>,
-        layers: Vec<(LayerFileName, Generation)>,
-    ) -> anyhow::Result<()> {
-        let mut guard = self.upload_queue.lock().unwrap();
-        let upload_queue = guard.initialized_mut()?;
-
-        self.schedule_deletion_of_unlinked0(upload_queue, layers);
-        self.launch_queued_tasks(upload_queue);
-        Ok(())
-    }
-
-    fn schedule_deletion_of_unlinked0(
-        self: &Arc<Self>,
-        upload_queue: &mut UploadQueueInitialized,
-        with_generations: Vec<(LayerFileName, Generation)>,
-    ) {
-        for (name, gen) in &with_generations {
-            info!("scheduling deletion of layer {}{}", name, gen.get_suffix());
-        }
-
-        #[cfg(feature = "testing")]
-        for (name, gen) in &with_generations {
-            match upload_queue.dangling_files.remove(name) {
-                Some(same) if &same == gen => { /* expected */ }
-                Some(other) => {
-                    tracing::error!("{name} was unlinked with {other:?} but deleted with {gen:?}");
-                }
-                None => {
-                    tracing::error!("{name} was unlinked but was not dangling");
-                }
+            for (name, gen) in &with_generations {
+                info!("scheduling deletion of layer {}{}", name, gen.get_suffix());
             }
-        }
 
-        // schedule the actual deletions
-        let op = UploadOp::Delete(Delete {
-            layers: with_generations,
-        });
-        self.calls_unfinished_metric_begin(&op);
-        upload_queue.queued_operations.push_back(op);
-    }
-
-    /// Schedules a compaction update to the remote `index_part.json`.
-    ///
-    /// `compacted_from` represent the L0 names which have been `compacted_to` L1 layers.
-    pub(crate) fn schedule_compaction_update(
-        self: &Arc<Self>,
-        compacted_from: &[Layer],
-        compacted_to: &[ResidentLayer],
-    ) -> anyhow::Result<()> {
-        let mut guard = self.upload_queue.lock().unwrap();
-        let upload_queue = guard.initialized_mut()?;
-
-        for layer in compacted_to {
-            self.schedule_layer_file_upload0(upload_queue, layer.clone());
-        }
-
-        let names = compacted_from.iter().map(|x| x.layer_desc().filename());
-
-        self.schedule_unlinking_of_layers_from_index_part0(upload_queue, names);
-        self.launch_queued_tasks(upload_queue);
+            // schedule the actual deletions
+            let op = UploadOp::Delete(Delete {
+                layers: with_generations,
+            });
+            self.calls_unfinished_metric_begin(&op);
+            upload_queue.queued_operations.push_back(op);
 
+            // Launch the tasks immediately, if possible
+            self.launch_queued_tasks(upload_queue);
+        };
+        no_bail_here();
         Ok(())
     }
 
@@ -1177,12 +1093,16 @@ impl RemoteTimelineClient {
             }
 
             let upload_result: anyhow::Result<()> = match &task.op {
-                UploadOp::UploadLayer(ref layer, ref layer_metadata) => {
-                    let path = layer.local_path();
+                UploadOp::UploadLayer(ref layer_file_name, ref layer_metadata) => {
+                    let path = self
+                        .conf
+                        .timeline_path(&self.tenant_id, &self.timeline_id)
+                        .join(layer_file_name.file_name());
+
                     upload::upload_timeline_layer(
                         self.conf,
                         &self.storage_impl,
-                        path,
+                        &path,
                         layer_metadata,
                         self.generation,
                     )
@@ -1456,8 +1376,6 @@ impl RemoteTimelineClient {
                         num_inprogress_deletions: 0,
                         inprogress_tasks: HashMap::default(),
                         queued_operations: VecDeque::default(),
-                        #[cfg(feature = "testing")]
-                        dangling_files: HashMap::default(),
                     };
 
                     let upload_queue = std::mem::replace(
@@ -1588,7 +1506,6 @@ mod tests {
         context::RequestContext,
         tenant::{
             harness::{TenantHarness, TIMELINE_ID},
-            storage_layer::Layer,
             Generation, Tenant, Timeline,
         },
         DEFAULT_PG_VERSION,
@@ -1731,11 +1648,7 @@ mod tests {
         let client = timeline.remote_client.as_ref().unwrap();
 
         // Download back the index.json, and check that the list of files is correct
-        let initial_index_part = match client
-            .download_index_file(CancellationToken::new())
-            .await
-            .unwrap()
-        {
+        let initial_index_part = match client.download_index_file().await.unwrap() {
             MaybeDeletedIndexPart::IndexPart(index_part) => index_part,
             MaybeDeletedIndexPart::Deleted(_) => panic!("unexpectedly got deleted index part"),
         };
@@ -1761,29 +1674,32 @@ mod tests {
         let generation = harness.generation;
 
         // Create a couple of dummy files,  schedule upload for them
+        let layer_file_name_1: LayerFileName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap();
+        let layer_file_name_2: LayerFileName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D9-00000000016B5A52".parse().unwrap();
+        let layer_file_name_3: LayerFileName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59DA-00000000016B5A53".parse().unwrap();
+        let content_1 = dummy_contents("foo");
+        let content_2 = dummy_contents("bar");
+        let content_3 = dummy_contents("baz");
 
-        let layers = [
-            ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap(), dummy_contents("foo")),
-            ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D9-00000000016B5A52".parse().unwrap(), dummy_contents("bar")),
-            ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59DA-00000000016B5A53".parse().unwrap(), dummy_contents("baz"))
-        ]
-        .into_iter()
-        .map(|(name, contents): (LayerFileName, Vec<u8>)| {
-            std::fs::write(timeline_path.join(name.file_name()), &contents).unwrap();
-
-            Layer::for_resident(
-                harness.conf,
-                &timeline,
-                name,
-                LayerFileMetadata::new(contents.len() as u64, generation),
-            )
-        }).collect::<Vec<_>>();
+        for (filename, content) in [
+            (&layer_file_name_1, &content_1),
+            (&layer_file_name_2, &content_2),
+            (&layer_file_name_3, &content_3),
+        ] {
+            std::fs::write(timeline_path.join(filename.file_name()), content).unwrap();
+        }
 
         client
-            .schedule_layer_file_upload(layers[0].clone())
+            .schedule_layer_file_upload(
+                &layer_file_name_1,
+                &LayerFileMetadata::new(content_1.len() as u64, generation),
+            )
             .unwrap();
         client
-            .schedule_layer_file_upload(layers[1].clone())
+            .schedule_layer_file_upload(
+                &layer_file_name_2,
+                &LayerFileMetadata::new(content_2.len() as u64, generation),
+            )
             .unwrap();
 
         // Check that they are started immediately, not queued
@@ -1824,11 +1740,7 @@ mod tests {
         }
 
         // Download back the index.json, and check that the list of files is correct
-        let index_part = match client
-            .download_index_file(CancellationToken::new())
-            .await
-            .unwrap()
-        {
+        let index_part = match client.download_index_file().await.unwrap() {
             MaybeDeletedIndexPart::IndexPart(index_part) => index_part,
             MaybeDeletedIndexPart::Deleted(_) => panic!("unexpectedly got deleted index part"),
         };
@@ -1841,42 +1753,38 @@ mod tests {
                 .collect(),
             &[
                 &initial_layer.file_name(),
-                &layers[0].layer_desc().filename().file_name(),
-                &layers[1].layer_desc().filename().file_name(),
+                &layer_file_name_1.file_name(),
+                &layer_file_name_2.file_name(),
             ],
         );
         assert_eq!(index_part.metadata, metadata);
 
         // Schedule upload and then a deletion. Check that the deletion is queued
         client
-            .schedule_layer_file_upload(layers[2].clone())
+            .schedule_layer_file_upload(
+                &layer_file_name_3,
+                &LayerFileMetadata::new(content_3.len() as u64, generation),
+            )
             .unwrap();
-
-        // this is no longer consistent with how deletion works with Layer::drop, but in this test
-        // keep using schedule_layer_file_deletion because we don't have a way to wait for the
-        // spawn_blocking started by the drop.
         client
-            .schedule_layer_file_deletion(&[layers[0].layer_desc().filename()])
+            .schedule_layer_file_deletion([layer_file_name_1.clone()].to_vec())
             .unwrap();
         {
             let mut guard = client.upload_queue.lock().unwrap();
             let upload_queue = guard.initialized_mut().unwrap();
 
             // Deletion schedules upload of the index file, and the file deletion itself
-            assert_eq!(upload_queue.queued_operations.len(), 2);
-            assert_eq!(upload_queue.inprogress_tasks.len(), 1);
-            assert_eq!(upload_queue.num_inprogress_layer_uploads, 1);
-            assert_eq!(upload_queue.num_inprogress_deletions, 0);
-            assert_eq!(
-                upload_queue.latest_files_changes_since_metadata_upload_scheduled,
-                0
-            );
+            assert!(upload_queue.queued_operations.len() == 2);
+            assert!(upload_queue.inprogress_tasks.len() == 1);
+            assert!(upload_queue.num_inprogress_layer_uploads == 1);
+            assert!(upload_queue.num_inprogress_deletions == 0);
+            assert!(upload_queue.latest_files_changes_since_metadata_upload_scheduled == 0);
         }
         assert_remote_files(
             &[
                 &initial_layer.file_name(),
-                &layers[0].layer_desc().filename().file_name(),
-                &layers[1].layer_desc().filename().file_name(),
+                &layer_file_name_1.file_name(),
+                &layer_file_name_2.file_name(),
                 "index_part.json",
             ],
             &remote_timeline_dir,
@@ -1890,8 +1798,8 @@ mod tests {
         assert_remote_files(
             &[
                 &initial_layer.file_name(),
-                &layers[1].layer_desc().filename().file_name(),
-                &layers[2].layer_desc().filename().file_name(),
+                &layer_file_name_2.file_name(),
+                &layer_file_name_3.file_name(),
                 "index_part.json",
             ],
             &remote_timeline_dir,
@@ -1920,13 +1828,6 @@ mod tests {
         )
         .unwrap();
 
-        let layer_file_1 = Layer::for_resident(
-            harness.conf,
-            &timeline,
-            layer_file_name_1.clone(),
-            LayerFileMetadata::new(content_1.len() as u64, harness.generation),
-        );
-
         #[derive(Debug, PartialEq, Clone, Copy)]
         struct BytesStartedFinished {
             started: Option<usize>,
@@ -1962,7 +1863,10 @@ mod tests {
         let actual_a = get_bytes_started_stopped();
 
         client
-            .schedule_layer_file_upload(layer_file_1.clone())
+            .schedule_layer_file_upload(
+                &layer_file_name_1,
+                &LayerFileMetadata::new(content_1.len() as u64, harness.generation),
+            )
             .unwrap();
 
         let actual_b = get_bytes_started_stopped();
@@ -2027,7 +1931,7 @@ mod tests {
         let client = test_state.build_client(get_generation);
 
         let download_r = client
-            .download_index_file(CancellationToken::new())
+            .download_index_file()
             .await
             .expect("download should always succeed");
         assert!(matches!(download_r, MaybeDeletedIndexPart::IndexPart(_)));

pageserver/src/tenant/remote_timeline_client/download.rs

@@ -19,7 +19,7 @@ use crate::tenant::remote_timeline_client::{remote_layer_path, remote_timelines_
 use crate::tenant::storage_layer::LayerFileName;
 use crate::tenant::timeline::span::debug_assert_current_span_has_tenant_and_timeline_id;
 use crate::tenant::Generation;
-use remote_storage::{DownloadError, GenericRemoteStorage, ListingMode};
+use remote_storage::{DownloadError, GenericRemoteStorage};
 use utils::crashsafe::path_with_suffix_extension;
 use utils::id::{TenantId, TimelineId};
 
@@ -170,43 +170,47 @@ pub fn is_temp_download_file(path: &Utf8Path) -> bool {
 pub async fn list_remote_timelines(
     storage: &GenericRemoteStorage,
     tenant_id: TenantId,
-    cancel: CancellationToken,
-) -> anyhow::Result<(HashSet<TimelineId>, HashSet<String>)> {
+) -> anyhow::Result<HashSet<TimelineId>> {
     let remote_path = remote_timelines_path(&tenant_id);
 
     fail::fail_point!("storage-sync-list-remote-timelines", |_| {
         anyhow::bail!("storage-sync-list-remote-timelines");
     });
 
-    let listing = download_retry_forever(
-        || storage.list(Some(&remote_path), ListingMode::WithDelimiter),
-        &format!("list timelines for {tenant_id}"),
-        cancel,
+    let timelines = download_retry(
+        || storage.list_prefixes(Some(&remote_path)),
+        &format!("list prefixes for {tenant_id}"),
     )
     .await?;
 
-    let mut timeline_ids = HashSet::new();
-    let mut other_prefixes = HashSet::new();
+    if timelines.is_empty() {
+        anyhow::bail!("no timelines found on the remote storage")
+    }
 
-    for timeline_remote_storage_key in listing.prefixes {
+    let mut timeline_ids = HashSet::new();
+
+    for timeline_remote_storage_key in timelines {
         let object_name = timeline_remote_storage_key.object_name().ok_or_else(|| {
             anyhow::anyhow!("failed to get timeline id for remote tenant {tenant_id}")
         })?;
 
-        match object_name.parse::<TimelineId>() {
-            Ok(t) => timeline_ids.insert(t),
-            Err(_) => other_prefixes.insert(object_name.to_string()),
-        };
+        let timeline_id: TimelineId = object_name
+            .parse()
+            .with_context(|| format!("parse object name into timeline id '{object_name}'"))?;
+
+        // list_prefixes is assumed to return unique names. Ensure this here.
+        // NB: it's safer to bail out than warn-log this because the pageserver
+        //     needs to absolutely know about _all_ timelines that exist, so that
+        //     GC knows all the branchpoints. If we skipped over a timeline instead,
+        //     GC could delete a layer that's still needed by that timeline.
+        anyhow::ensure!(
+            !timeline_ids.contains(&timeline_id),
+            "list_prefixes contains duplicate timeline id {timeline_id}"
+        );
+        timeline_ids.insert(timeline_id);
     }
 
-    for key in listing.keys {
-        let object_name = key
-            .object_name()
-            .ok_or_else(|| anyhow::anyhow!("object name for key {key}"))?;
-        other_prefixes.insert(object_name.to_string());
-    }
-
-    Ok((timeline_ids, other_prefixes))
+    Ok(timeline_ids)
 }
 
 async fn do_download_index_part(
@@ -214,11 +218,10 @@ async fn do_download_index_part(
     tenant_id: &TenantId,
     timeline_id: &TimelineId,
     index_generation: Generation,
-    cancel: CancellationToken,
 ) -> Result<IndexPart, DownloadError> {
     let remote_path = remote_index_path(tenant_id, timeline_id, index_generation);
 
-    let index_part_bytes = download_retry_forever(
+    let index_part_bytes = download_retry(
         || async {
             let mut index_part_download = storage.download(&remote_path).await?;
 
@@ -233,7 +236,6 @@ async fn do_download_index_part(
             Ok(index_part_bytes)
         },
         &format!("download {remote_path:?}"),
-        cancel,
     )
     .await?;
 
@@ -255,28 +257,19 @@ pub(super) async fn download_index_part(
     tenant_id: &TenantId,
     timeline_id: &TimelineId,
     my_generation: Generation,
-    cancel: CancellationToken,
 ) -> Result<IndexPart, DownloadError> {
     debug_assert_current_span_has_tenant_and_timeline_id();
 
     if my_generation.is_none() {
         // Operating without generations: just fetch the generation-less path
-        return do_download_index_part(storage, tenant_id, timeline_id, my_generation, cancel)
-            .await;
+        return do_download_index_part(storage, tenant_id, timeline_id, my_generation).await;
     }
 
     // Stale case: If we were intentionally attached in a stale generation, there may already be a remote
     // index in our generation.
     //
     // This is an optimization to avoid doing the listing for the general case below.
-    let res = do_download_index_part(
-        storage,
-        tenant_id,
-        timeline_id,
-        my_generation,
-        cancel.clone(),
-    )
-    .await;
+    let res = do_download_index_part(storage, tenant_id, timeline_id, my_generation).await;
     match res {
         Ok(index_part) => {
             tracing::debug!(
@@ -296,14 +289,8 @@ pub(super) async fn download_index_part(
     //    we want to find the most recent index from a previous generation.
     //
     // This is an optimization to avoid doing the listing for the general case below.
-    let res = do_download_index_part(
-        storage,
-        tenant_id,
-        timeline_id,
-        my_generation.previous(),
-        cancel.clone(),
-    )
-    .await;
+    let res =
+        do_download_index_part(storage, tenant_id, timeline_id, my_generation.previous()).await;
     match res {
         Ok(index_part) => {
             tracing::debug!("Found index_part from previous generation");
@@ -347,14 +334,13 @@ pub(super) async fn download_index_part(
     match max_previous_generation {
         Some(g) => {
             tracing::debug!("Found index_part in generation {g:?}");
-            do_download_index_part(storage, tenant_id, timeline_id, g, cancel).await
+            do_download_index_part(storage, tenant_id, timeline_id, g).await
         }
         None => {
             // Migration from legacy pre-generation state: we have a generation but no prior
             // attached pageservers did.  Try to load from a no-generation path.
             tracing::info!("No index_part.json* found");
-            do_download_index_part(storage, tenant_id, timeline_id, Generation::none(), cancel)
-                .await
+            do_download_index_part(storage, tenant_id, timeline_id, Generation::none()).await
         }
     }
 }
@@ -384,23 +370,3 @@ where
     )
     .await
 }
-
-async fn download_retry_forever<T, O, F>(
-    op: O,
-    description: &str,
-    cancel: CancellationToken,
-) -> Result<T, DownloadError>
-where
-    O: FnMut() -> F,
-    F: Future<Output = Result<T, DownloadError>>,
-{
-    backoff::retry(
-        op,
-        |e| matches!(e, DownloadError::BadInput(_) | DownloadError::NotFound),
-        FAILED_DOWNLOAD_WARN_THRESHOLD,
-        u32::MAX,
-        description,
-        backoff::Cancel::new(cancel, || DownloadError::Cancelled),
-    )
-    .await
-}

pageserver/src/tenant/remote_timeline_client/index.rs

@@ -98,7 +98,7 @@ impl IndexPart {
     const LATEST_VERSION: usize = 4;
 
     // Versions we may see when reading from a bucket.
-    pub const KNOWN_VERSIONS: &'static [usize] = &[1, 2, 3, 4];
+    pub const KNOWN_VERSIONS: &[usize] = &[1, 2, 3, 4];
 
     pub const FILE_NAME: &'static str = "index_part.json";
 

pageserver/src/tenant/remote_timeline_client/upload.rs

@@ -60,8 +60,6 @@ pub(super) async fn upload_timeline_layer<'a>(
         bail!("failpoint before-upload-layer")
     });
 
-    pausable_failpoint!("before-upload-layer-pausable");
-
     let storage_path = remote_path(conf, source_path, generation)?;
     let source_file_res = fs::File::open(&source_path).await;
     let source_file = match source_file_res {
@@ -72,8 +70,6 @@ pub(super) async fn upload_timeline_layer<'a>(
             // upload. However, a nonexistent file can also be indicative of
             // something worse, like when a file is scheduled for upload before
             // it has been written to disk yet.
-            //
-            // This is tested against `test_compaction_delete_before_upload`
             info!(path = %source_path, "File to upload doesn't exist. Likely the file has been deleted and an upload is not required any more.");
             return Ok(());
         }

pageserver/src/tenant/storage_layer.rs

@@ -4,21 +4,26 @@ pub mod delta_layer;
 mod filename;
 mod image_layer;
 mod inmemory_layer;
-mod layer;
 mod layer_desc;
+mod remote_layer;
 
+use crate::config::PageServerConf;
 use crate::context::{AccessStatsBehavior, RequestContext};
+use crate::repository::Key;
 use crate::task_mgr::TaskKind;
 use crate::walrecord::NeonWalRecord;
+use anyhow::Result;
 use bytes::Bytes;
+use camino::Utf8PathBuf;
 use enum_map::EnumMap;
 use enumset::EnumSet;
 use once_cell::sync::Lazy;
+use pageserver_api::models::LayerAccessKind;
 use pageserver_api::models::{
-    LayerAccessKind, LayerResidenceEvent, LayerResidenceEventReason, LayerResidenceStatus,
+    HistoricLayerInfo, LayerResidenceEvent, LayerResidenceEventReason, LayerResidenceStatus,
 };
 use std::ops::Range;
-use std::sync::Mutex;
+use std::sync::{Arc, Mutex};
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 use tracing::warn;
 use utils::history_buffer::HistoryBufferWithDropCounter;
@@ -34,8 +39,7 @@ pub use filename::{DeltaFileName, ImageFileName, LayerFileName};
 pub use image_layer::{ImageLayer, ImageLayerWriter};
 pub use inmemory_layer::InMemoryLayer;
 pub use layer_desc::{PersistentLayerDesc, PersistentLayerKey};
-
-pub(crate) use layer::{EvictionError, Layer, ResidentLayer};
+pub use remote_layer::RemoteLayer;
 
 pub fn range_overlaps<T>(a: &Range<T>, b: &Range<T>) -> bool
 where
@@ -70,7 +74,7 @@ pub struct ValueReconstructState {
     pub img: Option<(Lsn, Bytes)>,
 }
 
-/// Return value from [`Layer::get_value_reconstruct_data`]
+/// Return value from Layer::get_page_reconstruct_data
 #[derive(Clone, Copy, Debug)]
 pub enum ValueReconstructResult {
     /// Got all the data needed to reconstruct the requested page
@@ -175,6 +179,26 @@ impl LayerAccessStats {
         new
     }
 
+    /// Creates a clone of `self` and records `new_status` in the clone.
+    ///
+    /// The `new_status` is not recorded in `self`.
+    ///
+    /// See [`record_residence_event`] for why you need to do this while holding the layer map lock.
+    ///
+    /// [`record_residence_event`]: Self::record_residence_event
+    pub(crate) fn clone_for_residence_change(
+        &self,
+        new_status: LayerResidenceStatus,
+    ) -> LayerAccessStats {
+        let clone = {
+            let inner = self.0.lock().unwrap();
+            inner.clone()
+        };
+        let new = LayerAccessStats(Mutex::new(clone));
+        new.record_residence_event(new_status, LayerResidenceEventReason::ResidenceChange);
+        new
+    }
+
     /// Record a change in layer residency.
     ///
     /// Recording the event must happen while holding the layer map lock to
@@ -297,12 +321,95 @@ impl LayerAccessStats {
     }
 }
 
+/// Supertrait of the [`Layer`] trait that captures the bare minimum interface
+/// required by [`LayerMap`](super::layer_map::LayerMap).
+///
+/// All layers should implement a minimal `std::fmt::Debug` without tenant or
+/// timeline names, because those are known in the context of which the layers
+/// are used in (timeline).
+#[async_trait::async_trait]
+pub trait Layer: std::fmt::Debug + std::fmt::Display + Send + Sync + 'static {
+    ///
+    /// Return data needed to reconstruct given page at LSN.
+    ///
+    /// It is up to the caller to collect more data from previous layer and
+    /// perform WAL redo, if necessary.
+    ///
+    /// See PageReconstructResult for possible return values. The collected data
+    /// is appended to reconstruct_data; the caller should pass an empty struct
+    /// on first call, or a struct with a cached older image of the page if one
+    /// is available. If this returns ValueReconstructResult::Continue, look up
+    /// the predecessor layer and call again with the same 'reconstruct_data' to
+    /// collect more data.
+    async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_data: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> Result<ValueReconstructResult>;
+}
+
 /// Get a layer descriptor from a layer.
 pub trait AsLayerDesc {
     /// Get the layer descriptor.
     fn layer_desc(&self) -> &PersistentLayerDesc;
 }
 
+/// A Layer contains all data in a "rectangle" consisting of a range of keys and
+/// 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 are
+/// immutable. This trait presents the common functionality of in-memory and
+/// on-disk layers.
+///
+/// Furthermore, there are two kinds of on-disk layers: delta and image layers.
+/// A delta layer contains all modifications within a range of LSNs and keys.
+/// An image layer is a snapshot of all the data in a key-range, at a single
+/// LSN.
+pub trait PersistentLayer: Layer + AsLayerDesc {
+    /// File name used for this layer, both in the pageserver's local filesystem
+    /// state as well as in the remote storage.
+    fn filename(&self) -> LayerFileName {
+        self.layer_desc().filename()
+    }
+
+    // Path to the layer file in the local filesystem.
+    // `None` for `RemoteLayer`.
+    fn local_path(&self) -> Option<Utf8PathBuf>;
+
+    /// Permanently remove this layer from disk.
+    fn delete_resident_layer_file(&self) -> Result<()>;
+
+    fn downcast_remote_layer(self: Arc<Self>) -> Option<std::sync::Arc<RemoteLayer>> {
+        None
+    }
+
+    fn downcast_delta_layer(self: Arc<Self>) -> Option<std::sync::Arc<DeltaLayer>> {
+        None
+    }
+
+    fn is_remote_layer(&self) -> bool {
+        false
+    }
+
+    fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo;
+
+    fn access_stats(&self) -> &LayerAccessStats;
+}
+
+pub fn downcast_remote_layer(
+    layer: &Arc<dyn PersistentLayer>,
+) -> Option<std::sync::Arc<RemoteLayer>> {
+    if layer.is_remote_layer() {
+        Arc::clone(layer).downcast_remote_layer()
+    } else {
+        None
+    }
+}
+
 pub mod tests {
     use super::*;
 
@@ -340,6 +447,19 @@ pub mod tests {
     }
 }
 
+/// Helper enum to hold a PageServerConf, or a path
+///
+/// This is used by DeltaLayer and ImageLayer. Normally, this holds a reference to the
+/// global config, and paths to layer files are constructed using the tenant/timeline
+/// path from the config. But in the 'pagectl' binary, we need to construct a Layer
+/// struct for a file on disk, without having a page server running, so that we have no
+/// config. In that case, we use the Path variant to hold the full path to the file on
+/// disk.
+enum PathOrConf {
+    Path(Utf8PathBuf),
+    Conf(&'static PageServerConf),
+}
+
 /// Range wrapping newtype, which uses display to render Debug.
 ///
 /// Useful with `Key`, which has too verbose `{:?}` for printing multiple layers.

pageserver/src/tenant/storage_layer/delta_layer.rs

@@ -34,17 +34,18 @@ use crate::repository::{Key, Value, KEY_SIZE};
 use crate::tenant::blob_io::BlobWriter;
 use crate::tenant::block_io::{BlockBuf, BlockCursor, BlockLease, BlockReader, FileBlockReader};
 use crate::tenant::disk_btree::{DiskBtreeBuilder, DiskBtreeReader, VisitDirection};
-use crate::tenant::storage_layer::{Layer, ValueReconstructResult, ValueReconstructState};
-use crate::tenant::Timeline;
+use crate::tenant::storage_layer::{
+    PersistentLayer, ValueReconstructResult, ValueReconstructState,
+};
 use crate::virtual_file::VirtualFile;
 use crate::{walrecord, TEMP_FILE_SUFFIX};
 use crate::{DELTA_FILE_MAGIC, STORAGE_FORMAT_VERSION};
 use anyhow::{bail, ensure, Context, Result};
 use camino::{Utf8Path, Utf8PathBuf};
-use pageserver_api::models::LayerAccessKind;
+use pageserver_api::models::{HistoricLayerInfo, LayerAccessKind};
 use rand::{distributions::Alphanumeric, Rng};
 use serde::{Deserialize, Serialize};
-use std::fs::File;
+use std::fs::{self, File};
 use std::io::SeekFrom;
 use std::ops::Range;
 use std::os::unix::fs::FileExt;
@@ -58,7 +59,10 @@ use utils::{
     lsn::Lsn,
 };
 
-use super::{AsLayerDesc, LayerAccessStats, PersistentLayerDesc, ResidentLayer};
+use super::{
+    AsLayerDesc, DeltaFileName, Layer, LayerAccessStats, LayerAccessStatsReset, PathOrConf,
+    PersistentLayerDesc,
+};
 
 ///
 /// Header stored in the beginning of the file
@@ -178,12 +182,20 @@ impl DeltaKey {
     }
 }
 
-/// This is used only from `pagectl`. Within pageserver, all layers are
-/// [`crate::tenant::storage_layer::Layer`], which can hold a [`DeltaLayerInner`].
+/// DeltaLayer is the in-memory data structure associated with an on-disk delta
+/// file.
+///
+/// We keep a DeltaLayer in memory for each file, in the LayerMap. If a layer
+/// is in "loaded" state, we have a copy of the index in memory, in 'inner'.
+/// Otherwise the struct is just a placeholder for a file that exists on disk,
+/// and it needs to be loaded before using it in queries.
 pub struct DeltaLayer {
-    path: Utf8PathBuf,
+    path_or_conf: PathOrConf,
+
     pub desc: PersistentLayerDesc,
+
     access_stats: LayerAccessStats,
+
     inner: OnceCell<Arc<DeltaLayerInner>>,
 }
 
@@ -200,8 +212,6 @@ impl std::fmt::Debug for DeltaLayer {
     }
 }
 
-/// `DeltaLayerInner` is the in-memory data structure associated with an on-disk delta
-/// file.
 pub struct DeltaLayerInner {
     // values copied from summary
     index_start_blk: u32,
@@ -211,6 +221,12 @@ pub struct DeltaLayerInner {
     file: FileBlockReader,
 }
 
+impl AsRef<DeltaLayerInner> for DeltaLayerInner {
+    fn as_ref(&self) -> &DeltaLayerInner {
+        self
+    }
+}
+
 impl std::fmt::Debug for DeltaLayerInner {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("DeltaLayerInner")
@@ -220,6 +236,19 @@ impl std::fmt::Debug for DeltaLayerInner {
     }
 }
 
+#[async_trait::async_trait]
+impl Layer for DeltaLayer {
+    async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_state: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<ValueReconstructResult> {
+        self.get_value_reconstruct_data(key, lsn_range, reconstruct_state, ctx)
+            .await
+    }
+}
 /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
 impl std::fmt::Display for DeltaLayer {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
@@ -233,9 +262,40 @@ impl AsLayerDesc for DeltaLayer {
     }
 }
 
+impl PersistentLayer for DeltaLayer {
+    fn downcast_delta_layer(self: Arc<Self>) -> Option<std::sync::Arc<DeltaLayer>> {
+        Some(self)
+    }
+
+    fn local_path(&self) -> Option<Utf8PathBuf> {
+        self.local_path()
+    }
+
+    fn delete_resident_layer_file(&self) -> Result<()> {
+        self.delete_resident_layer_file()
+    }
+
+    fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
+        self.info(reset)
+    }
+
+    fn access_stats(&self) -> &LayerAccessStats {
+        self.access_stats()
+    }
+}
+
 impl DeltaLayer {
     pub(crate) async fn dump(&self, verbose: bool, ctx: &RequestContext) -> Result<()> {
-        self.desc.dump();
+        println!(
+            "----- delta layer for ten {} tli {} keys {}-{} lsn {}-{} size {} ----",
+            self.desc.tenant_id,
+            self.desc.timeline_id,
+            self.desc.key_range.start,
+            self.desc.key_range.end,
+            self.desc.lsn_range.start,
+            self.desc.lsn_range.end,
+            self.desc.file_size,
+        );
 
         if !verbose {
             return Ok(());
@@ -243,7 +303,119 @@ impl DeltaLayer {
 
         let inner = self.load(LayerAccessKind::Dump, ctx).await?;
 
-        inner.dump(ctx).await
+        println!(
+            "index_start_blk: {}, root {}",
+            inner.index_start_blk, inner.index_root_blk
+        );
+
+        let file = &inner.file;
+        let tree_reader = DiskBtreeReader::<_, DELTA_KEY_SIZE>::new(
+            inner.index_start_blk,
+            inner.index_root_blk,
+            file,
+        );
+
+        tree_reader.dump().await?;
+
+        let keys = DeltaLayerInner::load_keys(&inner, ctx).await?;
+
+        // A subroutine to dump a single blob
+        async fn dump_blob(val: ValueRef<'_>, ctx: &RequestContext) -> Result<String> {
+            let buf = val.reader.read_blob(val.blob_ref.pos(), ctx).await?;
+            let val = Value::des(&buf)?;
+            let desc = match val {
+                Value::Image(img) => {
+                    format!(" img {} bytes", img.len())
+                }
+                Value::WalRecord(rec) => {
+                    let wal_desc = walrecord::describe_wal_record(&rec)?;
+                    format!(
+                        " rec {} bytes will_init: {} {}",
+                        buf.len(),
+                        rec.will_init(),
+                        wal_desc
+                    )
+                }
+            };
+            Ok(desc)
+        }
+
+        for entry in keys {
+            let DeltaEntry { key, lsn, val, .. } = entry;
+            let desc = match dump_blob(val, ctx).await {
+                Ok(desc) => desc,
+                Err(err) => {
+                    let err: anyhow::Error = err;
+                    format!("ERROR: {err}")
+                }
+            };
+            println!("  key {key} at {lsn}: {desc}");
+        }
+
+        Ok(())
+    }
+
+    pub(crate) async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_state: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<ValueReconstructResult> {
+        ensure!(lsn_range.start >= self.desc.lsn_range.start);
+
+        ensure!(self.desc.key_range.contains(&key));
+
+        let inner = self
+            .load(LayerAccessKind::GetValueReconstructData, ctx)
+            .await?;
+        inner
+            .get_value_reconstruct_data(key, lsn_range, reconstruct_state, ctx)
+            .await
+    }
+
+    pub(crate) fn local_path(&self) -> Option<Utf8PathBuf> {
+        Some(self.path())
+    }
+
+    pub(crate) fn delete_resident_layer_file(&self) -> Result<()> {
+        // delete underlying file
+        fs::remove_file(self.path())?;
+        Ok(())
+    }
+
+    pub(crate) fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
+        let layer_file_name = self.layer_desc().filename().file_name();
+        let lsn_range = self.layer_desc().lsn_range.clone();
+
+        let access_stats = self.access_stats.as_api_model(reset);
+
+        HistoricLayerInfo::Delta {
+            layer_file_name,
+            layer_file_size: self.desc.file_size,
+            lsn_start: lsn_range.start,
+            lsn_end: lsn_range.end,
+            remote: false,
+            access_stats,
+        }
+    }
+
+    pub(crate) fn access_stats(&self) -> &LayerAccessStats {
+        &self.access_stats
+    }
+
+    fn path_for(
+        path_or_conf: &PathOrConf,
+        tenant_id: &TenantId,
+        timeline_id: &TimelineId,
+        fname: &DeltaFileName,
+    ) -> Utf8PathBuf {
+        match path_or_conf {
+            PathOrConf::Path(path) => path.clone(),
+            PathOrConf::Conf(conf) => conf
+                .timeline_path(tenant_id, timeline_id)
+                .join(fname.to_string()),
+        }
     }
 
     fn temp_path_for(
@@ -289,21 +461,52 @@ impl DeltaLayer {
     async fn load_inner(&self, ctx: &RequestContext) -> Result<Arc<DeltaLayerInner>> {
         let path = self.path();
 
-        let loaded = DeltaLayerInner::load(&path, None, ctx).await?;
+        let summary = match &self.path_or_conf {
+            PathOrConf::Conf(_) => Some(Summary::from(self)),
+            PathOrConf::Path(_) => None,
+        };
 
-        // not production code
-        let actual_filename = path.file_name().unwrap().to_owned();
-        let expected_filename = self.layer_desc().filename().file_name();
+        let loaded = DeltaLayerInner::load(&path, summary, ctx).await?;
 
-        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);
+        if let PathOrConf::Path(ref path) = self.path_or_conf {
+            // not production code
+
+            let actual_filename = path.file_name().unwrap().to_owned();
+            let expected_filename = self.filename().file_name();
+
+            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);
+            }
         }
 
         Ok(Arc::new(loaded))
     }
 
+    /// Create a DeltaLayer struct representing an existing file on disk.
+    pub fn new(
+        conf: &'static PageServerConf,
+        timeline_id: TimelineId,
+        tenant_id: TenantId,
+        filename: &DeltaFileName,
+        file_size: u64,
+        access_stats: LayerAccessStats,
+    ) -> DeltaLayer {
+        DeltaLayer {
+            path_or_conf: PathOrConf::Conf(conf),
+            desc: PersistentLayerDesc::new_delta(
+                tenant_id,
+                timeline_id,
+                filename.key_range.clone(),
+                filename.lsn_range.clone(),
+                file_size,
+            ),
+            access_stats,
+            inner: OnceCell::new(),
+        }
+    }
+
     /// Create a DeltaLayer struct representing an existing file on disk.
     ///
     /// This variant is only used for debugging purposes, by the 'pagectl' binary.
@@ -317,7 +520,7 @@ impl DeltaLayer {
             .context("get file metadata to determine size")?;
 
         Ok(DeltaLayer {
-            path: path.to_path_buf(),
+            path_or_conf: PathOrConf::Path(path.to_path_buf()),
             desc: PersistentLayerDesc::new_delta(
                 summary.tenant_id,
                 summary.timeline_id,
@@ -330,9 +533,29 @@ impl DeltaLayer {
         })
     }
 
+    fn layer_name(&self) -> DeltaFileName {
+        self.desc.delta_file_name()
+    }
     /// Path to the layer file in pageserver workdir.
-    fn path(&self) -> Utf8PathBuf {
-        self.path.clone()
+    pub fn path(&self) -> Utf8PathBuf {
+        Self::path_for(
+            &self.path_or_conf,
+            &self.desc.tenant_id,
+            &self.desc.timeline_id,
+            &self.layer_name(),
+        )
+    }
+    /// Loads all keys stored in the layer. Returns key, lsn, value size and value reference.
+    ///
+    /// The value can be obtained via the [`ValueRef::load`] function.
+    pub(crate) async fn load_keys(&self, ctx: &RequestContext) -> Result<Vec<DeltaEntry<'_>>> {
+        let inner = self
+            .load(LayerAccessKind::KeyIter, ctx)
+            .await
+            .context("load delta layer keys")?;
+        DeltaLayerInner::load_keys(inner, ctx)
+            .await
+            .context("Layer index is corrupted")
     }
 }
 
@@ -437,7 +660,7 @@ impl DeltaLayerWriterInner {
     ///
     /// Finish writing the delta layer.
     ///
-    async fn finish(self, key_end: Key, timeline: &Arc<Timeline>) -> anyhow::Result<ResidentLayer> {
+    async fn finish(self, key_end: Key) -> anyhow::Result<DeltaLayer> {
         let index_start_blk =
             ((self.blob_writer.size() + PAGE_SZ as u64 - 1) / PAGE_SZ as u64) as u32;
 
@@ -494,21 +717,37 @@ impl DeltaLayerWriterInner {
         // Note: Because we opened the file in write-only mode, we cannot
         // reuse the same VirtualFile for reading later. That's why we don't
         // set inner.file here. The first read will have to re-open it.
-
-        let desc = PersistentLayerDesc::new_delta(
-            self.tenant_id,
-            self.timeline_id,
-            self.key_start..key_end,
-            self.lsn_range.clone(),
-            metadata.len(),
-        );
+        let layer = DeltaLayer {
+            path_or_conf: PathOrConf::Conf(self.conf),
+            desc: PersistentLayerDesc::new_delta(
+                self.tenant_id,
+                self.timeline_id,
+                self.key_start..key_end,
+                self.lsn_range.clone(),
+                metadata.len(),
+            ),
+            access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
+            inner: OnceCell::new(),
+        };
 
         // fsync the file
         file.sync_all().await?;
+        // Rename the file to its final name
+        //
+        // Note: This overwrites any existing file. There shouldn't be any.
+        // FIXME: throw an error instead?
+        let final_path = DeltaLayer::path_for(
+            &PathOrConf::Conf(self.conf),
+            &self.tenant_id,
+            &self.timeline_id,
+            &DeltaFileName {
+                key_range: self.key_start..key_end,
+                lsn_range: self.lsn_range,
+            },
+        );
+        std::fs::rename(self.path, &final_path)?;
 
-        let layer = Layer::finish_creating(self.conf, timeline, desc, &self.path)?;
-
-        trace!("created delta layer {}", layer.local_path());
+        trace!("created delta layer {final_path}");
 
         Ok(layer)
     }
@@ -589,12 +828,8 @@ impl DeltaLayerWriter {
     ///
     /// Finish writing the delta layer.
     ///
-    pub(crate) async fn finish(
-        mut self,
-        key_end: Key,
-        timeline: &Arc<Timeline>,
-    ) -> anyhow::Result<ResidentLayer> {
-        self.inner.take().unwrap().finish(key_end, timeline).await
+    pub async fn finish(mut self, key_end: Key) -> anyhow::Result<DeltaLayer> {
+        self.inner.take().unwrap().finish(key_end).await
     }
 }
 
@@ -732,17 +967,15 @@ impl DeltaLayerInner {
         }
     }
 
-    pub(super) async fn load_keys<'a>(
-        &'a self,
-        ctx: &RequestContext,
+    pub(super) async fn load_keys<'a, 'b, T: AsRef<DeltaLayerInner> + Clone>(
+        this: &'a T,
+        ctx: &'b RequestContext,
     ) -> Result<Vec<DeltaEntry<'a>>> {
-        let file = &self.file;
+        let dl = this.as_ref();
+        let file = &dl.file;
 
-        let tree_reader = DiskBtreeReader::<_, DELTA_KEY_SIZE>::new(
-            self.index_start_blk,
-            self.index_root_blk,
-            file,
-        );
+        let tree_reader =
+            DiskBtreeReader::<_, DELTA_KEY_SIZE>::new(dl.index_start_blk, dl.index_root_blk, file);
 
         let mut all_keys: Vec<DeltaEntry<'_>> = Vec::new();
 
@@ -755,7 +988,7 @@ impl DeltaLayerInner {
                     let val_ref = ValueRef {
                         blob_ref: BlobRef(value),
                         reader: BlockCursor::new(crate::tenant::block_io::BlockReaderRef::Adapter(
-                            Adapter(self),
+                            Adapter(dl),
                         )),
                     };
                     let pos = BlobRef(value).pos();
@@ -782,61 +1015,10 @@ impl DeltaLayerInner {
         if let Some(last) = all_keys.last_mut() {
             // Last key occupies all space till end of value storage,
             // which corresponds to beginning of the index
-            last.size = self.index_start_blk as u64 * PAGE_SZ as u64 - last.size;
+            last.size = dl.index_start_blk as u64 * PAGE_SZ as u64 - last.size;
         }
         Ok(all_keys)
     }
-
-    pub(super) async fn dump(&self, ctx: &RequestContext) -> anyhow::Result<()> {
-        println!(
-            "index_start_blk: {}, root {}",
-            self.index_start_blk, self.index_root_blk
-        );
-
-        let file = &self.file;
-        let tree_reader = DiskBtreeReader::<_, DELTA_KEY_SIZE>::new(
-            self.index_start_blk,
-            self.index_root_blk,
-            file,
-        );
-
-        tree_reader.dump().await?;
-
-        let keys = self.load_keys(ctx).await?;
-
-        async fn dump_blob(val: ValueRef<'_>, ctx: &RequestContext) -> anyhow::Result<String> {
-            let buf = val.reader.read_blob(val.blob_ref.pos(), ctx).await?;
-            let val = Value::des(&buf)?;
-            let desc = match val {
-                Value::Image(img) => {
-                    format!(" img {} bytes", img.len())
-                }
-                Value::WalRecord(rec) => {
-                    let wal_desc = walrecord::describe_wal_record(&rec)?;
-                    format!(
-                        " rec {} bytes will_init: {} {}",
-                        buf.len(),
-                        rec.will_init(),
-                        wal_desc
-                    )
-                }
-            };
-            Ok(desc)
-        }
-
-        for entry in keys {
-            let DeltaEntry { key, lsn, val, .. } = entry;
-            let desc = match dump_blob(val, ctx).await {
-                Ok(desc) => desc,
-                Err(err) => {
-                    format!("ERROR: {err}")
-                }
-            };
-            println!("  key {key} at {lsn}: {desc}");
-        }
-
-        Ok(())
-    }
 }
 
 /// A set of data associated with a delta layer key and its value
@@ -876,9 +1058,3 @@ impl<T: AsRef<DeltaLayerInner>> Adapter<T> {
         self.0.as_ref().file.read_blk(blknum, ctx).await
     }
 }
-
-impl AsRef<DeltaLayerInner> for DeltaLayerInner {
-    fn as_ref(&self) -> &DeltaLayerInner {
-        self
-    }
-}

pageserver/src/tenant/storage_layer/filename.rs

@@ -226,14 +226,6 @@ impl LayerFileName {
             _ => false,
         }
     }
-
-    pub(crate) fn kind(&self) -> &'static str {
-        use LayerFileName::*;
-        match self {
-            Delta(_) => "delta",
-            Image(_) => "image",
-        }
-    }
 }
 
 impl fmt::Display for LayerFileName {

pageserver/src/tenant/storage_layer/image_layer.rs

@@ -31,23 +31,21 @@ use crate::tenant::blob_io::BlobWriter;
 use crate::tenant::block_io::{BlockBuf, BlockReader, FileBlockReader};
 use crate::tenant::disk_btree::{DiskBtreeBuilder, DiskBtreeReader, VisitDirection};
 use crate::tenant::storage_layer::{
-    LayerAccessStats, ValueReconstructResult, ValueReconstructState,
+    LayerAccessStats, PersistentLayer, ValueReconstructResult, ValueReconstructState,
 };
-use crate::tenant::Timeline;
 use crate::virtual_file::VirtualFile;
 use crate::{IMAGE_FILE_MAGIC, STORAGE_FORMAT_VERSION, TEMP_FILE_SUFFIX};
 use anyhow::{bail, ensure, Context, Result};
 use bytes::Bytes;
 use camino::{Utf8Path, Utf8PathBuf};
 use hex;
-use pageserver_api::models::LayerAccessKind;
+use pageserver_api::models::{HistoricLayerInfo, LayerAccessKind};
 use rand::{distributions::Alphanumeric, Rng};
 use serde::{Deserialize, Serialize};
-use std::fs::File;
+use std::fs::{self, File};
 use std::io::SeekFrom;
 use std::ops::Range;
 use std::os::unix::prelude::FileExt;
-use std::sync::Arc;
 use tokio::sync::OnceCell;
 use tracing::*;
 
@@ -58,7 +56,7 @@ use utils::{
 };
 
 use super::filename::ImageFileName;
-use super::{AsLayerDesc, Layer, PersistentLayerDesc, ResidentLayer};
+use super::{AsLayerDesc, Layer, LayerAccessStatsReset, PathOrConf, PersistentLayerDesc};
 
 ///
 /// Header stored in the beginning of the file
@@ -116,14 +114,22 @@ impl Summary {
     }
 }
 
-/// This is used only from `pagectl`. Within pageserver, all layers are
-/// [`crate::tenant::storage_layer::Layer`], which can hold an [`ImageLayerInner`].
+/// ImageLayer is the in-memory data structure associated with an on-disk image
+/// file.
+///
+/// We keep an ImageLayer in memory for each file, in the LayerMap. If a layer
+/// is in "loaded" state, we have a copy of the index in memory, in 'inner'.
+/// Otherwise the struct is just a placeholder for a file that exists on disk,
+/// and it needs to be loaded before using it in queries.
 pub struct ImageLayer {
-    path: Utf8PathBuf,
+    path_or_conf: PathOrConf,
+
     pub desc: PersistentLayerDesc,
     // This entry contains an image of all pages as of this LSN, should be the same as desc.lsn
     pub lsn: Lsn,
+
     access_stats: LayerAccessStats,
+
     inner: OnceCell<ImageLayerInner>,
 }
 
@@ -140,8 +146,6 @@ impl std::fmt::Debug for ImageLayer {
     }
 }
 
-/// ImageLayer is the in-memory data structure associated with an on-disk image
-/// file.
 pub struct ImageLayerInner {
     // values copied from summary
     index_start_blk: u32,
@@ -162,11 +166,73 @@ impl std::fmt::Debug for ImageLayerInner {
     }
 }
 
-impl ImageLayerInner {
-    pub(super) async fn dump(&self, ctx: &RequestContext) -> anyhow::Result<()> {
-        let file = &self.file;
+#[async_trait::async_trait]
+impl Layer for ImageLayer {
+    /// Look up given page in the file
+    async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_state: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<ValueReconstructResult> {
+        self.get_value_reconstruct_data(key, lsn_range, reconstruct_state, ctx)
+            .await
+    }
+}
+
+/// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+impl std::fmt::Display for ImageLayer {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.layer_desc().short_id())
+    }
+}
+
+impl AsLayerDesc for ImageLayer {
+    fn layer_desc(&self) -> &PersistentLayerDesc {
+        &self.desc
+    }
+}
+
+impl PersistentLayer for ImageLayer {
+    fn local_path(&self) -> Option<Utf8PathBuf> {
+        self.local_path()
+    }
+
+    fn delete_resident_layer_file(&self) -> Result<()> {
+        self.delete_resident_layer_file()
+    }
+
+    fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
+        self.info(reset)
+    }
+
+    fn access_stats(&self) -> &LayerAccessStats {
+        self.access_stats()
+    }
+}
+
+impl ImageLayer {
+    pub(crate) async fn dump(&self, verbose: bool, ctx: &RequestContext) -> Result<()> {
+        println!(
+            "----- image layer for ten {} tli {} key {}-{} at {} is_incremental {} size {} ----",
+            self.desc.tenant_id,
+            self.desc.timeline_id,
+            self.desc.key_range.start,
+            self.desc.key_range.end,
+            self.lsn,
+            self.desc.is_incremental(),
+            self.desc.file_size
+        );
+
+        if !verbose {
+            return Ok(());
+        }
+
+        let inner = self.load(LayerAccessKind::Dump, ctx).await?;
+        let file = &inner.file;
         let tree_reader =
-            DiskBtreeReader::<_, KEY_SIZE>::new(self.index_start_blk, self.index_root_blk, file);
+            DiskBtreeReader::<_, KEY_SIZE>::new(inner.index_start_blk, inner.index_root_blk, file);
 
         tree_reader.dump().await?;
 
@@ -184,36 +250,69 @@ impl ImageLayerInner {
 
         Ok(())
     }
-}
 
-/// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
-impl std::fmt::Display for ImageLayer {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "{}", self.layer_desc().short_id())
+    pub(crate) async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_state: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<ValueReconstructResult> {
+        assert!(self.desc.key_range.contains(&key));
+        assert!(lsn_range.start >= self.lsn);
+        assert!(lsn_range.end >= self.lsn);
+
+        let inner = self
+            .load(LayerAccessKind::GetValueReconstructData, ctx)
+            .await?;
+        inner
+            .get_value_reconstruct_data(key, reconstruct_state, ctx)
+            .await
+            // FIXME: makes no sense to dump paths
+            .with_context(|| format!("read {}", self.path()))
     }
-}
 
-impl AsLayerDesc for ImageLayer {
-    fn layer_desc(&self) -> &PersistentLayerDesc {
-        &self.desc
+    pub(crate) fn local_path(&self) -> Option<Utf8PathBuf> {
+        Some(self.path())
     }
-}
-
-impl ImageLayer {
-    pub(crate) async fn dump(&self, verbose: bool, ctx: &RequestContext) -> Result<()> {
-        self.desc.dump();
-
-        if !verbose {
-            return Ok(());
-        }
-
-        let inner = self.load(LayerAccessKind::Dump, ctx).await?;
-
-        inner.dump(ctx).await?;
 
+    pub(crate) fn delete_resident_layer_file(&self) -> Result<()> {
+        // delete underlying file
+        fs::remove_file(self.path())?;
         Ok(())
     }
 
+    pub(crate) fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
+        let layer_file_name = self.layer_desc().filename().file_name();
+        let lsn_start = self.layer_desc().image_layer_lsn();
+
+        HistoricLayerInfo::Image {
+            layer_file_name,
+            layer_file_size: self.desc.file_size,
+            lsn_start,
+            remote: false,
+            access_stats: self.access_stats.as_api_model(reset),
+        }
+    }
+
+    pub(crate) fn access_stats(&self) -> &LayerAccessStats {
+        &self.access_stats
+    }
+
+    fn path_for(
+        path_or_conf: &PathOrConf,
+        timeline_id: TimelineId,
+        tenant_id: TenantId,
+        fname: &ImageFileName,
+    ) -> Utf8PathBuf {
+        match path_or_conf {
+            PathOrConf::Path(path) => path.to_path_buf(),
+            PathOrConf::Conf(conf) => conf
+                .timeline_path(&tenant_id, &timeline_id)
+                .join(fname.to_string()),
+        }
+    }
+
     fn temp_path_for(
         conf: &PageServerConf,
         timeline_id: TimelineId,
@@ -249,21 +348,54 @@ impl ImageLayer {
     async fn load_inner(&self, ctx: &RequestContext) -> Result<ImageLayerInner> {
         let path = self.path();
 
-        let loaded = ImageLayerInner::load(&path, self.desc.image_layer_lsn(), None, ctx).await?;
+        let expected_summary = match &self.path_or_conf {
+            PathOrConf::Conf(_) => Some(Summary::from(self)),
+            PathOrConf::Path(_) => None,
+        };
 
-        // not production code
-        let actual_filename = path.file_name().unwrap().to_owned();
-        let expected_filename = self.layer_desc().filename().file_name();
+        let loaded =
+            ImageLayerInner::load(&path, self.desc.image_layer_lsn(), expected_summary, ctx)
+                .await?;
 
-        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);
+        if let PathOrConf::Path(ref path) = self.path_or_conf {
+            // not production code
+            let actual_filename = path.file_name().unwrap().to_owned();
+            let expected_filename = self.filename().file_name();
+
+            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);
+            }
         }
 
         Ok(loaded)
     }
 
+    /// Create an ImageLayer struct representing an existing file on disk
+    pub fn new(
+        conf: &'static PageServerConf,
+        timeline_id: TimelineId,
+        tenant_id: TenantId,
+        filename: &ImageFileName,
+        file_size: u64,
+        access_stats: LayerAccessStats,
+    ) -> ImageLayer {
+        ImageLayer {
+            path_or_conf: PathOrConf::Conf(conf),
+            desc: PersistentLayerDesc::new_img(
+                tenant_id,
+                timeline_id,
+                filename.key_range.clone(),
+                filename.lsn,
+                file_size,
+            ), // Now we assume image layer ALWAYS covers the full range. This may change in the future.
+            lsn: filename.lsn,
+            access_stats,
+            inner: OnceCell::new(),
+        }
+    }
+
     /// Create an ImageLayer struct representing an existing file on disk.
     ///
     /// This variant is only used for debugging purposes, by the 'pagectl' binary.
@@ -275,7 +407,7 @@ impl ImageLayer {
             .metadata()
             .context("get file metadata to determine size")?;
         Ok(ImageLayer {
-            path: path.to_path_buf(),
+            path_or_conf: PathOrConf::Path(path.to_path_buf()),
             desc: PersistentLayerDesc::new_img(
                 summary.tenant_id,
                 summary.timeline_id,
@@ -289,8 +421,18 @@ impl ImageLayer {
         })
     }
 
-    fn path(&self) -> Utf8PathBuf {
-        self.path.clone()
+    fn layer_name(&self) -> ImageFileName {
+        self.desc.image_file_name()
+    }
+
+    /// Path to the layer file in pageserver workdir.
+    pub fn path(&self) -> Utf8PathBuf {
+        Self::path_for(
+            &self.path_or_conf,
+            self.desc.timeline_id,
+            self.desc.tenant_id,
+            &self.layer_name(),
+        )
     }
 }
 
@@ -462,7 +604,7 @@ impl ImageLayerWriterInner {
     ///
     /// Finish writing the image layer.
     ///
-    async fn finish(self, timeline: &Arc<Timeline>) -> anyhow::Result<ResidentLayer> {
+    async fn finish(self) -> anyhow::Result<ImageLayer> {
         let index_start_blk =
             ((self.blob_writer.size() + PAGE_SZ as u64 - 1) / PAGE_SZ as u64) as u32;
 
@@ -516,14 +658,33 @@ impl ImageLayerWriterInner {
         // Note: Because we open the file in write-only mode, we cannot
         // reuse the same VirtualFile for reading later. That's why we don't
         // set inner.file here. The first read will have to re-open it.
+        let layer = ImageLayer {
+            path_or_conf: PathOrConf::Conf(self.conf),
+            desc,
+            lsn: self.lsn,
+            access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
+            inner: OnceCell::new(),
+        };
 
         // fsync the file
         file.sync_all().await?;
 
-        // FIXME: why not carry the virtualfile here, it supports renaming?
-        let layer = Layer::finish_creating(self.conf, timeline, desc, &self.path)?;
+        // Rename the file to its final name
+        //
+        // Note: This overwrites any existing file. There shouldn't be any.
+        // FIXME: throw an error instead?
+        let final_path = ImageLayer::path_for(
+            &PathOrConf::Conf(self.conf),
+            self.timeline_id,
+            self.tenant_id,
+            &ImageFileName {
+                key_range: self.key_range.clone(),
+                lsn: self.lsn,
+            },
+        );
+        std::fs::rename(self.path, final_path)?;
 
-        trace!("created image layer {}", layer.local_path());
+        trace!("created image layer {}", layer.path());
 
         Ok(layer)
     }
@@ -585,11 +746,8 @@ impl ImageLayerWriter {
     ///
     /// Finish writing the image layer.
     ///
-    pub(crate) async fn finish(
-        mut self,
-        timeline: &Arc<Timeline>,
-    ) -> anyhow::Result<super::ResidentLayer> {
-        self.inner.take().unwrap().finish(timeline).await
+    pub async fn finish(mut self) -> anyhow::Result<ImageLayer> {
+        self.inner.take().unwrap().finish().await
     }
 }
 

pageserver/src/tenant/storage_layer/inmemory_layer.rs

@@ -10,12 +10,11 @@ use crate::repository::{Key, Value};
 use crate::tenant::block_io::BlockReader;
 use crate::tenant::ephemeral_file::EphemeralFile;
 use crate::tenant::storage_layer::{ValueReconstructResult, ValueReconstructState};
-use crate::tenant::Timeline;
 use crate::walrecord;
 use anyhow::{ensure, Result};
 use pageserver_api::models::InMemoryLayerInfo;
 use std::collections::HashMap;
-use std::sync::{Arc, OnceLock};
+use std::sync::OnceLock;
 use tracing::*;
 use utils::{
     bin_ser::BeSer,
@@ -29,7 +28,7 @@ use std::fmt::Write as _;
 use std::ops::Range;
 use tokio::sync::RwLock;
 
-use super::{DeltaLayerWriter, ResidentLayer};
+use super::{DeltaLayer, DeltaLayerWriter, Layer};
 
 pub struct InMemoryLayer {
     conf: &'static PageServerConf,
@@ -208,6 +207,20 @@ impl InMemoryLayer {
     }
 }
 
+#[async_trait::async_trait]
+impl Layer for InMemoryLayer {
+    async fn get_value_reconstruct_data(
+        &self,
+        key: Key,
+        lsn_range: Range<Lsn>,
+        reconstruct_data: &mut ValueReconstructState,
+        ctx: &RequestContext,
+    ) -> Result<ValueReconstructResult> {
+        self.get_value_reconstruct_data(key, lsn_range, reconstruct_data, ctx)
+            .await
+    }
+}
+
 impl std::fmt::Display for InMemoryLayer {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let end_lsn = self.end_lsn_or_max();
@@ -216,13 +229,17 @@ impl std::fmt::Display for InMemoryLayer {
 }
 
 impl InMemoryLayer {
+    ///
     /// Get layer size.
+    ///
     pub async fn size(&self) -> Result<u64> {
         let inner = self.inner.read().await;
         Ok(inner.file.len())
     }
 
+    ///
     /// Create a new, empty, in-memory layer
+    ///
     pub async fn create(
         conf: &'static PageServerConf,
         timeline_id: TimelineId,
@@ -314,11 +331,7 @@ impl InMemoryLayer {
     /// Write this frozen in-memory layer to disk.
     ///
     /// Returns a new delta layer with all the same data as this in-memory layer
-    pub(crate) async fn write_to_disk(
-        &self,
-        timeline: &Arc<Timeline>,
-        ctx: &RequestContext,
-    ) -> Result<ResidentLayer> {
+    pub(crate) async fn write_to_disk(&self, ctx: &RequestContext) -> Result<DeltaLayer> {
         // 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 acquire the
         // write lock on it, so we shouldn't block anyone. There's one exception
@@ -363,8 +376,7 @@ impl InMemoryLayer {
             }
         }
 
-        // MAX is used here because we identify L0 layers by full key range
-        let delta_layer = delta_layer_writer.finish(Key::MAX, timeline).await?;
+        let delta_layer = delta_layer_writer.finish(Key::MAX).await?;
         Ok(delta_layer)
     }
 }

pageserver/src/tenant/storage_layer/layer_desc.rs

@@ -1,3 +1,4 @@
+use anyhow::Result;
 use core::fmt::Display;
 use std::ops::Range;
 use utils::{
@@ -5,7 +6,7 @@ use utils::{
     lsn::Lsn,
 };
 
-use crate::repository::Key;
+use crate::{context::RequestContext, repository::Key};
 
 use super::{DeltaFileName, ImageFileName, LayerFileName};
 
@@ -99,22 +100,6 @@ impl PersistentLayerDesc {
         }
     }
 
-    pub fn from_filename(
-        tenant_id: TenantId,
-        timeline_id: TimelineId,
-        filename: LayerFileName,
-        file_size: u64,
-    ) -> Self {
-        match filename {
-            LayerFileName::Image(i) => {
-                Self::new_img(tenant_id, timeline_id, i.key_range, i.lsn, file_size)
-            }
-            LayerFileName::Delta(d) => {
-                Self::new_delta(tenant_id, timeline_id, d.key_range, d.lsn_range, file_size)
-            }
-        }
-    }
-
     /// Get the LSN that the image layer covers.
     pub fn image_layer_lsn(&self) -> Lsn {
         assert!(!self.is_delta);
@@ -188,31 +173,21 @@ impl PersistentLayerDesc {
         self.is_delta
     }
 
-    pub fn dump(&self) {
-        if self.is_delta {
-            println!(
-                "----- delta layer for ten {} tli {} keys {}-{} lsn {}-{} is_incremental {} size {} ----",
-                self.tenant_id,
-                self.timeline_id,
-                self.key_range.start,
-                self.key_range.end,
-                self.lsn_range.start,
-                self.lsn_range.end,
-                self.is_incremental(),
-                self.file_size,
-            );
-        } else {
-            println!(
-                "----- image layer for ten {} tli {} key {}-{} at {} is_incremental {} size {} ----",
-                self.tenant_id,
-                self.timeline_id,
-                self.key_range.start,
-                self.key_range.end,
-                self.image_layer_lsn(),
-                self.is_incremental(),
-                self.file_size
-            );
-        }
+    pub fn dump(&self, _verbose: bool, _ctx: &RequestContext) -> Result<()> {
+        println!(
+            "----- layer for ten {} tli {} keys {}-{} lsn {}-{} is_delta {} is_incremental {} size {} ----",
+            self.tenant_id,
+            self.timeline_id,
+            self.key_range.start,
+            self.key_range.end,
+            self.lsn_range.start,
+            self.lsn_range.end,
+            self.is_delta,
+            self.is_incremental(),
+            self.file_size,
+        );
+
+        Ok(())
     }
 
     pub fn file_size(&self) -> u64 {

pageserver/src/tenant/storage_layer/remote_layer.rs

@@ -0,0 +1,216 @@
+//! A RemoteLayer is an in-memory placeholder for a layer file that exists
+//! in remote storage.
+//!
+use crate::config::PageServerConf;
+use crate::context::RequestContext;
+use crate::repository::Key;
+use crate::tenant::remote_timeline_client::index::LayerFileMetadata;
+use crate::tenant::storage_layer::{Layer, ValueReconstructResult, ValueReconstructState};
+use crate::tenant::timeline::layer_manager::LayerManager;
+use anyhow::{bail, Result};
+use camino::Utf8PathBuf;
+use pageserver_api::models::HistoricLayerInfo;
+use std::ops::Range;
+use std::sync::Arc;
+
+use utils::{
+    id::{TenantId, TimelineId},
+    lsn::Lsn,
+};
+
+use super::filename::{DeltaFileName, ImageFileName};
+use super::{
+    AsLayerDesc, DeltaLayer, ImageLayer, LayerAccessStats, LayerAccessStatsReset,
+    LayerResidenceStatus, PersistentLayer, PersistentLayerDesc,
+};
+
+/// RemoteLayer is a not yet downloaded [`ImageLayer`] or
+/// [`DeltaLayer`](super::DeltaLayer).
+///
+/// RemoteLayer might be downloaded on-demand during operations which are
+/// allowed download remote layers and during which, it gets replaced with a
+/// concrete `DeltaLayer` or `ImageLayer`.
+///
+/// See: [`crate::context::RequestContext`] for authorization to download
+pub struct RemoteLayer {
+    pub desc: PersistentLayerDesc,
+
+    pub layer_metadata: LayerFileMetadata,
+
+    access_stats: LayerAccessStats,
+
+    pub(crate) ongoing_download: Arc<tokio::sync::Semaphore>,
+
+    /// Has `LayerMap::replace` failed for this (true) or not (false).
+    ///
+    /// Used together with [`ongoing_download`] semaphore in `Timeline::download_remote_layer`.
+    /// The field is used to mark a RemoteLayer permanently (until restart or ignore+load)
+    /// unprocessable, because a LayerMap::replace failed.
+    ///
+    /// It is very unlikely to accumulate these in the Timeline's LayerMap, but having this avoids
+    /// a possible fast loop between `Timeline::get_reconstruct_data` and
+    /// `Timeline::download_remote_layer`, which also logs.
+    ///
+    /// [`ongoing_download`]: Self::ongoing_download
+    pub(crate) download_replacement_failure: std::sync::atomic::AtomicBool,
+}
+
+impl std::fmt::Debug for RemoteLayer {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("RemoteLayer")
+            .field("file_name", &self.desc.filename())
+            .field("layer_metadata", &self.layer_metadata)
+            .field("is_incremental", &self.desc.is_incremental())
+            .finish()
+    }
+}
+
+#[async_trait::async_trait]
+impl Layer for RemoteLayer {
+    async fn get_value_reconstruct_data(
+        &self,
+        _key: Key,
+        _lsn_range: Range<Lsn>,
+        _reconstruct_state: &mut ValueReconstructState,
+        _ctx: &RequestContext,
+    ) -> Result<ValueReconstructResult> {
+        Err(anyhow::anyhow!("layer {self} needs to be downloaded"))
+    }
+}
+
+/// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+impl std::fmt::Display for RemoteLayer {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.layer_desc().short_id())
+    }
+}
+
+impl AsLayerDesc for RemoteLayer {
+    fn layer_desc(&self) -> &PersistentLayerDesc {
+        &self.desc
+    }
+}
+
+impl PersistentLayer for RemoteLayer {
+    fn local_path(&self) -> Option<Utf8PathBuf> {
+        None
+    }
+
+    fn delete_resident_layer_file(&self) -> Result<()> {
+        bail!("remote layer has no layer file");
+    }
+
+    fn downcast_remote_layer<'a>(self: Arc<Self>) -> Option<std::sync::Arc<RemoteLayer>> {
+        Some(self)
+    }
+
+    fn is_remote_layer(&self) -> bool {
+        true
+    }
+
+    fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
+        let layer_file_name = self.layer_desc().filename().file_name();
+        let lsn_range = self.layer_desc().lsn_range.clone();
+
+        if self.desc.is_delta {
+            HistoricLayerInfo::Delta {
+                layer_file_name,
+                layer_file_size: self.layer_metadata.file_size(),
+                lsn_start: lsn_range.start,
+                lsn_end: lsn_range.end,
+                remote: true,
+                access_stats: self.access_stats.as_api_model(reset),
+            }
+        } else {
+            HistoricLayerInfo::Image {
+                layer_file_name,
+                layer_file_size: self.layer_metadata.file_size(),
+                lsn_start: lsn_range.start,
+                remote: true,
+                access_stats: self.access_stats.as_api_model(reset),
+            }
+        }
+    }
+
+    fn access_stats(&self) -> &LayerAccessStats {
+        &self.access_stats
+    }
+}
+
+impl RemoteLayer {
+    pub fn new_img(
+        tenantid: TenantId,
+        timelineid: TimelineId,
+        fname: &ImageFileName,
+        layer_metadata: &LayerFileMetadata,
+        access_stats: LayerAccessStats,
+    ) -> RemoteLayer {
+        RemoteLayer {
+            desc: PersistentLayerDesc::new_img(
+                tenantid,
+                timelineid,
+                fname.key_range.clone(),
+                fname.lsn,
+                layer_metadata.file_size(),
+            ),
+            layer_metadata: layer_metadata.clone(),
+            ongoing_download: Arc::new(tokio::sync::Semaphore::new(1)),
+            download_replacement_failure: std::sync::atomic::AtomicBool::default(),
+            access_stats,
+        }
+    }
+
+    pub fn new_delta(
+        tenantid: TenantId,
+        timelineid: TimelineId,
+        fname: &DeltaFileName,
+        layer_metadata: &LayerFileMetadata,
+        access_stats: LayerAccessStats,
+    ) -> RemoteLayer {
+        RemoteLayer {
+            desc: PersistentLayerDesc::new_delta(
+                tenantid,
+                timelineid,
+                fname.key_range.clone(),
+                fname.lsn_range.clone(),
+                layer_metadata.file_size(),
+            ),
+            layer_metadata: layer_metadata.clone(),
+            ongoing_download: Arc::new(tokio::sync::Semaphore::new(1)),
+            download_replacement_failure: std::sync::atomic::AtomicBool::default(),
+            access_stats,
+        }
+    }
+
+    /// Create a Layer struct representing this layer, after it has been downloaded.
+    pub(crate) fn create_downloaded_layer(
+        &self,
+        _layer_map_lock_held_witness: &LayerManager,
+        conf: &'static PageServerConf,
+        file_size: u64,
+    ) -> Arc<dyn PersistentLayer> {
+        if self.desc.is_delta {
+            let fname = self.desc.delta_file_name();
+            Arc::new(DeltaLayer::new(
+                conf,
+                self.desc.timeline_id,
+                self.desc.tenant_id,
+                &fname,
+                file_size,
+                self.access_stats
+                    .clone_for_residence_change(LayerResidenceStatus::Resident),
+            ))
+        } else {
+            let fname = self.desc.image_file_name();
+            Arc::new(ImageLayer::new(
+                conf,
+                self.desc.timeline_id,
+                self.desc.tenant_id,
+                &fname,
+                file_size,
+                self.access_stats
+                    .clone_for_residence_change(LayerResidenceStatus::Resident),
+            ))
+        }
+    }
+}

pageserver/src/tenant/tasks.rs

@@ -12,74 +12,7 @@ use crate::task_mgr::{TaskKind, BACKGROUND_RUNTIME};
 use crate::tenant::{Tenant, TenantState};
 use tokio_util::sync::CancellationToken;
 use tracing::*;
-use utils::{backoff, completion};
-
-static CONCURRENT_BACKGROUND_TASKS: once_cell::sync::Lazy<tokio::sync::Semaphore> =
-    once_cell::sync::Lazy::new(|| {
-        let total_threads = *task_mgr::BACKGROUND_RUNTIME_WORKER_THREADS;
-        let permits = usize::max(
-            1,
-            // while a lot of the work is done on spawn_blocking, we still do
-            // repartitioning in the async context. this should give leave us some workers
-            // unblocked to be blocked on other work, hopefully easing any outside visible
-            // effects of restarts.
-            //
-            // 6/8 is a guess; previously we ran with unlimited 8 and more from
-            // spawn_blocking.
-            (total_threads * 3).checked_div(4).unwrap_or(0),
-        );
-        assert_ne!(permits, 0, "we will not be adding in permits later");
-        assert!(
-            permits < total_threads,
-            "need threads avail for shorter work"
-        );
-        tokio::sync::Semaphore::new(permits)
-    });
-
-#[derive(Debug, PartialEq, Eq, Clone, Copy, strum_macros::IntoStaticStr)]
-#[strum(serialize_all = "snake_case")]
-pub(crate) enum BackgroundLoopKind {
-    Compaction,
-    Gc,
-    Eviction,
-    ConsumptionMetricsCollectMetrics,
-    ConsumptionMetricsSyntheticSizeWorker,
-}
-
-impl BackgroundLoopKind {
-    fn as_static_str(&self) -> &'static str {
-        let s: &'static str = self.into();
-        s
-    }
-}
-
-pub(crate) enum RateLimitError {
-    Cancelled,
-}
-
-pub(crate) async fn concurrent_background_tasks_rate_limit(
-    loop_kind: BackgroundLoopKind,
-    _ctx: &RequestContext,
-    cancel: &CancellationToken,
-) -> Result<impl Drop, RateLimitError> {
-    crate::metrics::BACKGROUND_LOOP_SEMAPHORE_WAIT_START_COUNT
-        .with_label_values(&[loop_kind.as_static_str()])
-        .inc();
-    scopeguard::defer!(
-        crate::metrics::BACKGROUND_LOOP_SEMAPHORE_WAIT_FINISH_COUNT.with_label_values(&[loop_kind.as_static_str()]).inc();
-    );
-    tokio::select! {
-        permit = CONCURRENT_BACKGROUND_TASKS.acquire() => {
-            match permit {
-                Ok(permit) => Ok(permit),
-                Err(_closed) => unreachable!("we never close the semaphore"),
-            }
-        },
-        _ = cancel.cancelled() => {
-            Err(RateLimitError::Cancelled)
-        }
-    }
-}
+use utils::completion;
 
 /// Start per tenant background loops: compaction and gc.
 pub fn start_background_loops(
@@ -139,10 +72,7 @@ pub fn start_background_loops(
 /// Compaction task's main loop
 ///
 async fn compaction_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
-    const MAX_BACKOFF_SECS: f64 = 300.0;
-    // How many errors we have seen consequtively
-    let mut error_run_count = 0;
-
+    let wait_duration = Duration::from_secs(2);
     TENANT_TASK_EVENTS.with_label_values(&["start"]).inc();
     async {
         let ctx = RequestContext::todo_child(TaskKind::Compaction, DownloadBehavior::Download);
@@ -179,24 +109,14 @@ async fn compaction_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
             } else {
                 // Run compaction
                 if let Err(e) = tenant.compaction_iteration(&cancel, &ctx).await {
-                    let wait_duration = backoff::exponential_backoff_duration_seconds(
-                        error_run_count,
-                        1.0,
-                        MAX_BACKOFF_SECS,
-                    );
-                    error_run_count += 1;
-                    error!(
-                        "Compaction failed {error_run_count} times, retrying in {:?}: {e:?}",
-                        wait_duration
-                    );
-                    Duration::from_secs_f64(wait_duration)
+                    error!("Compaction failed, retrying in {:?}: {e:?}", wait_duration);
+                    wait_duration
                 } else {
-                    error_run_count = 0;
                     period
                 }
             };
 
-            warn_when_period_overrun(started_at.elapsed(), period, BackgroundLoopKind::Compaction);
+            warn_when_period_overrun(started_at.elapsed(), period, "compaction");
 
             // Sleep
             if tokio::time::timeout(sleep_duration, cancel.cancelled())
@@ -215,10 +135,7 @@ async fn compaction_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
 /// GC task's main loop
 ///
 async fn gc_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
-    const MAX_BACKOFF_SECS: f64 = 300.0;
-    // How many errors we have seen consequtively
-    let mut error_run_count = 0;
-
+    let wait_duration = Duration::from_secs(2);
     TENANT_TASK_EVENTS.with_label_values(&["start"]).inc();
     async {
         // GC might require downloading, to find the cutoff LSN that corresponds to the
@@ -260,24 +177,14 @@ async fn gc_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
                     .gc_iteration(None, gc_horizon, tenant.get_pitr_interval(), &ctx)
                     .await;
                 if let Err(e) = res {
-                    let wait_duration = backoff::exponential_backoff_duration_seconds(
-                        error_run_count,
-                        1.0,
-                        MAX_BACKOFF_SECS,
-                    );
-                    error_run_count += 1;
-                    error!(
-                        "Gc failed {error_run_count} times, retrying in {:?}: {e:?}",
-                        wait_duration
-                    );
-                    Duration::from_secs_f64(wait_duration)
+                    error!("Gc failed, retrying in {:?}: {e:?}", wait_duration);
+                    wait_duration
                 } else {
-                    error_run_count = 0;
                     period
                 }
             };
 
-            warn_when_period_overrun(started_at.elapsed(), period, BackgroundLoopKind::Gc);
+            warn_when_period_overrun(started_at.elapsed(), period, "gc");
 
             // Sleep
             if tokio::time::timeout(sleep_duration, cancel.cancelled())
@@ -351,24 +258,20 @@ pub(crate) async fn random_init_delay(
 }
 
 /// Attention: the `task` and `period` beocme labels of a pageserver-wide prometheus metric.
-pub(crate) fn warn_when_period_overrun(
-    elapsed: Duration,
-    period: Duration,
-    task: BackgroundLoopKind,
-) {
+pub(crate) fn warn_when_period_overrun(elapsed: Duration, period: Duration, task: &str) {
     // Duration::ZERO will happen because it's the "disable [bgtask]" value.
     if elapsed >= period && period != Duration::ZERO {
         // humantime does no significant digits clamping whereas Duration's debug is a bit more
         // intelligent. however it makes sense to keep the "configuration format" for period, even
         // though there's no way to output the actual config value.
-        info!(
+        warn!(
             ?elapsed,
             period = %humantime::format_duration(period),
-            ?task,
+            task,
             "task iteration took longer than the configured period"
         );
         crate::metrics::BACKGROUND_LOOP_PERIOD_OVERRUN_COUNT
-            .with_label_values(&[task.as_static_str(), &format!("{}", period.as_secs())])
+            .with_label_values(&[task, &format!("{}", period.as_secs())])
             .inc();
     }
 }

pageserver/src/tenant/timeline/delete.rs

@@ -38,14 +38,6 @@ async fn stop_tasks(timeline: &Timeline) -> Result<(), DeleteTimelineError> {
     }
     debug!("wal receiver shutdown confirmed");
 
-    // Shut down the layer flush task before the remote client, as one depends on the other
-    task_mgr::shutdown_tasks(
-        Some(TaskKind::LayerFlushTask),
-        Some(timeline.tenant_id),
-        Some(timeline.timeline_id),
-    )
-    .await;
-
     // Prevent new uploads from starting.
     if let Some(remote_client) = timeline.remote_client.as_ref() {
         let res = remote_client.stop();
@@ -302,7 +294,6 @@ async fn cleanup_remaining_timeline_fs_traces(
     // Remove delete mark
     tokio::fs::remove_file(conf.timeline_delete_mark_file_path(tenant_id, timeline_id))
         .await
-        .or_else(fs_ext::ignore_not_found)
         .context("remove delete mark")
 }
 

pageserver/src/tenant/timeline/eviction_task.rs

@@ -29,7 +29,7 @@ use crate::{
     task_mgr::{self, TaskKind, BACKGROUND_RUNTIME},
     tenant::{
         config::{EvictionPolicy, EvictionPolicyLayerAccessThreshold},
-        tasks::{BackgroundLoopKind, RateLimitError},
+        storage_layer::PersistentLayer,
         timeline::EvictionError,
         LogicalSizeCalculationCause, Tenant,
     },
@@ -129,11 +129,7 @@ impl Timeline {
                     ControlFlow::Continue(()) => (),
                 }
                 let elapsed = start.elapsed();
-                crate::tenant::tasks::warn_when_period_overrun(
-                    elapsed,
-                    p.period,
-                    BackgroundLoopKind::Eviction,
-                );
+                crate::tenant::tasks::warn_when_period_overrun(elapsed, p.period, "eviction");
                 crate::metrics::EVICTION_ITERATION_DURATION
                     .get_metric_with_label_values(&[
                         &format!("{}", p.period.as_secs()),
@@ -154,17 +150,6 @@ impl Timeline {
     ) -> ControlFlow<()> {
         let now = SystemTime::now();
 
-        let _permit = match crate::tenant::tasks::concurrent_background_tasks_rate_limit(
-            BackgroundLoopKind::Eviction,
-            ctx,
-            cancel,
-        )
-        .await
-        {
-            Ok(permit) => permit,
-            Err(RateLimitError::Cancelled) => return ControlFlow::Break(()),
-        };
-
         // If we evict layers but keep cached values derived from those layers, then
         // we face a storm of on-demand downloads after pageserver restart.
         // The reason is that the restart empties the caches, and so, the values
@@ -209,26 +194,15 @@ impl Timeline {
         // NB: all the checks can be invalidated as soon as we release the layer map lock.
         // We don't want to hold the layer map lock during eviction.
         // So, we just need to deal with this.
-        let candidates: Vec<_> = {
+        let candidates: Vec<Arc<dyn PersistentLayer>> = {
             let guard = self.layers.read().await;
             let layers = guard.layer_map();
             let mut candidates = Vec::new();
             for hist_layer in layers.iter_historic_layers() {
                 let hist_layer = guard.get_from_desc(&hist_layer);
-
-                // guard against eviction while we inspect it; it might be that eviction_task and
-                // disk_usage_eviction_task both select the same layers to be evicted, and
-                // seemingly free up double the space. both succeeding is of no consequence.
-                let guard = match hist_layer.keep_resident().await {
-                    Ok(Some(l)) => l,
-                    Ok(None) => continue,
-                    Err(e) => {
-                        // these should not happen, but we cannot make them statically impossible right
-                        // now.
-                        tracing::warn!(layer=%hist_layer, "failed to keep the layer resident: {e:#}");
-                        continue;
-                    }
-                };
+                if hist_layer.is_remote_layer() {
+                    continue;
+                }
 
                 let last_activity_ts = hist_layer.access_stats().latest_activity().unwrap_or_else(|| {
                     // We only use this fallback if there's an implementation error.
@@ -259,7 +233,7 @@ impl Timeline {
                     }
                 };
                 if no_activity_for > p.threshold {
-                    candidates.push(guard.drop_eviction_guard())
+                    candidates.push(hist_layer)
                 }
             }
             candidates
@@ -278,7 +252,7 @@ impl Timeline {
         };
 
         let results = match self
-            .evict_layer_batch(remote_client, &candidates, cancel)
+            .evict_layer_batch(remote_client, &candidates[..], cancel.clone())
             .await
         {
             Err(pre_err) => {
@@ -289,7 +263,7 @@ impl Timeline {
             Ok(results) => results,
         };
         assert_eq!(results.len(), candidates.len());
-        for result in results {
+        for (l, result) in candidates.iter().zip(results) {
             match result {
                 None => {
                     stats.skipped_for_shutdown += 1;
@@ -297,10 +271,20 @@ impl Timeline {
                 Some(Ok(())) => {
                     stats.evicted += 1;
                 }
-                Some(Err(EvictionError::NotFound | EvictionError::Downloaded)) => {
+                Some(Err(EvictionError::CannotEvictRemoteLayer)) => {
+                    stats.not_evictable += 1;
+                }
+                Some(Err(EvictionError::FileNotFound)) => {
                     // compaction/gc removed the file while we were waiting on layer_removal_cs
                     stats.not_evictable += 1;
                 }
+                Some(Err(
+                    e @ EvictionError::LayerNotFound(_) | e @ EvictionError::StatFailed(_),
+                )) => {
+                    let e = utils::error::report_compact_sources(&e);
+                    warn!(layer = %l, "failed to evict layer: {e}");
+                    stats.not_evictable += 1;
+                }
             }
         }
         if stats.candidates == stats.not_evictable {

pageserver/src/tenant/timeline/init.rs

@@ -72,7 +72,7 @@ pub(super) fn scan_timeline_dir(path: &Utf8Path) -> anyhow::Result<Vec<Discovere
 }
 
 /// Decision on what to do with a layer file after considering its local and remote metadata.
-#[derive(Clone, Debug)]
+#[derive(Clone)]
 pub(super) enum Decision {
     /// The layer is not present locally.
     Evicted(LayerFileMetadata),
@@ -84,30 +84,27 @@ pub(super) enum Decision {
     },
     /// The layer is present locally, and metadata matches.
     UseLocal(LayerFileMetadata),
+    /// The layer is only known locally, it needs to be uploaded.
+    NeedsUpload(LayerFileMetadata),
 }
 
-/// A layer needs to be left out of the layer map.
+/// The related layer is is in future compared to disk_consistent_lsn, it must not be loaded.
 #[derive(Debug)]
-pub(super) enum DismissedLayer {
-    /// The related layer is is in future compared to disk_consistent_lsn, it must not be loaded.
-    Future {
-        /// The local metadata. `None` if the layer is only known through [`IndexPart`].
-        local: Option<LayerFileMetadata>,
-    },
-    /// The layer only exists locally.
-    ///
-    /// In order to make crash safe updates to layer map, we must dismiss layers which are only
-    /// found locally or not yet included in the remote `index_part.json`.
-    LocalOnly(LayerFileMetadata),
+pub(super) struct FutureLayer {
+    /// The local metadata. `None` if the layer is only known through [`IndexPart`].
+    pub(super) local: Option<LayerFileMetadata>,
 }
 
 /// Merges local discoveries and remote [`IndexPart`] to a collection of decisions.
+///
+/// This function should not gain additional reasons to fail than [`FutureLayer`], consider adding
+/// the checks earlier to [`scan_timeline_dir`].
 pub(super) fn reconcile(
     discovered: Vec<(LayerFileName, u64)>,
     index_part: Option<&IndexPart>,
     disk_consistent_lsn: Lsn,
     generation: Generation,
-) -> Vec<(LayerFileName, Result<Decision, DismissedLayer>)> {
+) -> Vec<(LayerFileName, Result<Decision, FutureLayer>)> {
     use Decision::*;
 
     // name => (local, remote)
@@ -145,19 +142,17 @@ pub(super) fn reconcile(
         .into_iter()
         .map(|(name, (local, remote))| {
             let decision = if name.is_in_future(disk_consistent_lsn) {
-                Err(DismissedLayer::Future { local })
+                Err(FutureLayer { local })
             } else {
-                match (local, remote) {
-                    (Some(local), Some(remote)) if local != remote => {
-                        Ok(UseRemote { local, remote })
-                    }
-                    (Some(x), Some(_)) => Ok(UseLocal(x)),
-                    (None, Some(x)) => Ok(Evicted(x)),
-                    (Some(x), None) => Err(DismissedLayer::LocalOnly(x)),
+                Ok(match (local, remote) {
+                    (Some(local), Some(remote)) if local != remote => UseRemote { local, remote },
+                    (Some(x), Some(_)) => UseLocal(x),
+                    (None, Some(x)) => Evicted(x),
+                    (Some(x), None) => NeedsUpload(x),
                     (None, None) => {
                         unreachable!("there must not be any non-local non-remote files")
                     }
-                }
+                })
             };
 
             (name, decision)
@@ -197,21 +192,14 @@ pub(super) fn cleanup_future_layer(
     name: &LayerFileName,
     disk_consistent_lsn: Lsn,
 ) -> anyhow::Result<()> {
+    use LayerFileName::*;
+    let kind = match name {
+        Delta(_) => "delta",
+        Image(_) => "image",
+    };
     // future image layers are allowed to be produced always for not yet flushed to disk
     // lsns stored in InMemoryLayer.
-    let kind = name.kind();
     tracing::info!("found future {kind} layer {name} disk_consistent_lsn is {disk_consistent_lsn}");
-    std::fs::remove_file(path)?;
-    Ok(())
-}
-
-pub(super) fn cleanup_local_only_file(
-    path: &Utf8Path,
-    name: &LayerFileName,
-    local: &LayerFileMetadata,
-) -> anyhow::Result<()> {
-    let kind = name.kind();
-    tracing::info!("found local-only {kind} layer {name}, metadata {local:?}");
-    std::fs::remove_file(path)?;
+    crate::tenant::timeline::rename_to_backup(path)?;
     Ok(())
 }