Add safekeeper option to patch control file.

https://github.com/neondatabase/neon/issues/6397
2026-06-26 16:50:37 +00:00 · 2024-01-21 00:22:30 +03:00
66 changed files with 1478 additions and 2527 deletions
--- a/.config/nextest.toml
+++ b/.config/nextest.toml
@@ -1,2 +1,2 @@
 [profile.default]
-slow-timeout = { period = "20s", terminate-after = 3 }
+slow-timeout = "1m"
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -10,9 +10,9 @@ checksum = "8b5ace29ee3216de37c0546865ad08edef58b0f9e76838ed8959a84a990e58c5"

 [[package]]
 name = "addr2line"
-version = "0.21.0"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a30b2e23b9e17a9f90641c7ab1549cd9b44f296d3ccbf309d2863cfe398a0cb"
+checksum = "a76fd60b23679b7d19bd066031410fb7e458ccc5e958eb5c325888ce4baedc97"
 dependencies = [
 "gimli",
 ]
@@ -840,15 +840,15 @@ dependencies = [

 [[package]]
 name = "backtrace"
-version = "0.3.69"
+version = "0.3.67"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2089b7e3f35b9dd2d0ed921ead4f6d318c27680d4a5bd167b3ee120edb105837"
+checksum = "233d376d6d185f2a3093e58f283f60f880315b6c60075b01f36b3b85154564ca"
 dependencies = [
 "addr2line",
 "cc",
 "cfg-if",
 "libc",
- "miniz_oxide",
+ "miniz_oxide 0.6.2",
 "object",
 "rustc-demangle",
 ]
@@ -1215,7 +1215,7 @@ dependencies = [
 "flate2",
 "futures",
 "hyper",
- "nix 0.27.1",
+ "nix 0.26.2",
 "notify",
 "num_cpus",
 "opentelemetry",
@@ -1331,7 +1331,7 @@ dependencies = [
 "git-version",
 "hex",
 "hyper",
- "nix 0.27.1",
+ "nix 0.26.2",
 "once_cell",
 "pageserver_api",
 "pageserver_client",
@@ -1872,13 +1872,13 @@ dependencies = [

 [[package]]
 name = "filetime"
-version = "0.2.22"
+version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d4029edd3e734da6fe05b6cd7bd2960760a616bd2ddd0d59a0124746d6272af0"
+checksum = "5cbc844cecaee9d4443931972e1289c8ff485cb4cc2767cb03ca139ed6885153"
 dependencies = [
 "cfg-if",
 "libc",
- "redox_syscall 0.3.5",
+ "redox_syscall 0.2.16",
 "windows-sys 0.48.0",
 ]

@@ -1895,7 +1895,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3b9429470923de8e8cbd4d2dc513535400b4b3fef0319fb5c4e1f520a7bef743"
 dependencies = [
 "crc32fast",
- "miniz_oxide",
+ "miniz_oxide 0.7.1",
 ]

 [[package]]
@@ -2093,9 +2093,9 @@ dependencies = [

 [[package]]
 name = "gimli"
-version = "0.28.1"
+version = "0.27.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4271d37baee1b8c7e4b708028c57d816cf9d2434acb33a549475f78c181f6253"
+checksum = "ad0a93d233ebf96623465aad4046a8d3aa4da22d4f4beba5388838c8a434bbb4"

 [[package]]
 name = "git-version"
@@ -2748,18 +2748,18 @@ checksum = "f665ee40bc4a3c5590afb1e9677db74a508659dfd71e126420da8274909a0167"

 [[package]]
 name = "memoffset"
-version = "0.8.0"
+version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d61c719bcfbcf5d62b3a09efa6088de8c54bc0bfcd3ea7ae39fcc186108b8de1"
+checksum = "5de893c32cde5f383baa4c04c5d6dbdd735cfd4a794b0debdb2bb1b421da5ff4"
 dependencies = [
 "autocfg",
 ]

 [[package]]
 name = "memoffset"
-version = "0.9.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a634b1c61a95585bd15607c6ab0c4e5b226e695ff2800ba0cdccddf208c406c"
+checksum = "d61c719bcfbcf5d62b3a09efa6088de8c54bc0bfcd3ea7ae39fcc186108b8de1"
 dependencies = [
 "autocfg",
 ]
@@ -2797,6 +2797,15 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"

+[[package]]
+name = "miniz_oxide"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b275950c28b37e794e8c55d88aeb5e139d0ce23fdbbeda68f8d7174abdf9e8fa"
+dependencies = [
+ "adler",
+]
+
 [[package]]
 name = "miniz_oxide"
 version = "0.7.1"
@@ -2856,14 +2865,16 @@ dependencies = [

 [[package]]
 name = "nix"
-version = "0.27.1"
+version = "0.26.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2eb04e9c688eff1c89d72b407f168cf79bb9e867a9d3323ed6c01519eb9cc053"
+checksum = "bfdda3d196821d6af13126e40375cdf7da646a96114af134d5f417a9a1dc8e1a"
 dependencies = [
- "bitflags 2.4.1",
+ "bitflags 1.3.2",
 "cfg-if",
 "libc",
- "memoffset 0.9.0",
+ "memoffset 0.7.1",
+ "pin-utils",
+ "static_assertions",
 ]

 [[package]]
@@ -2878,21 +2889,20 @@ dependencies = [

 [[package]]
 name = "notify"
-version = "6.1.1"
+version = "5.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6205bd8bb1e454ad2e27422015fb5e4f2bcc7e08fa8f27058670d208324a4d2d"
+checksum = "729f63e1ca555a43fe3efa4f3efdf4801c479da85b432242a7b726f353c88486"
 dependencies = [
- "bitflags 2.4.1",
+ "bitflags 1.3.2",
 "crossbeam-channel",
 "filetime",
 "fsevent-sys",
 "inotify 0.9.6",
 "kqueue",
 "libc",
- "log",
 "mio",
 "walkdir",
- "windows-sys 0.48.0",
+ "windows-sys 0.45.0",
 ]

 [[package]]
@@ -3018,9 +3028,9 @@ dependencies = [

 [[package]]
 name = "object"
-version = "0.32.2"
+version = "0.30.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a6a622008b6e321afc04970976f62ee297fdbaa6f95318ca343e3eebb9648441"
+checksum = "ea86265d3d3dcb6a27fc51bd29a4bf387fae9d2986b823079d4986af253eb439"
 dependencies = [
 "memchr",
 ]
@@ -3092,9 +3102,9 @@ dependencies = [

 [[package]]
 name = "opentelemetry"
-version = "0.20.0"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9591d937bc0e6d2feb6f71a559540ab300ea49955229c347a517a28d27784c54"
+checksum = "5f4b8347cc26099d3aeee044065ecc3ae11469796b4d65d065a23a584ed92a6f"
 dependencies = [
 "opentelemetry_api",
 "opentelemetry_sdk",
@@ -3102,9 +3112,9 @@ dependencies = [

 [[package]]
 name = "opentelemetry-http"
-version = "0.9.0"
+version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c7594ec0e11d8e33faf03530a4c49af7064ebba81c1480e01be67d90b356508b"
+checksum = "a819b71d6530c4297b49b3cae2939ab3a8cc1b9f382826a1bc29dd0ca3864906"
 dependencies = [
 "async-trait",
 "bytes",
@@ -3115,56 +3125,54 @@ dependencies = [

 [[package]]
 name = "opentelemetry-otlp"
-version = "0.13.0"
+version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7e5e5a5c4135864099f3faafbe939eb4d7f9b80ebf68a8448da961b32a7c1275"
+checksum = "8af72d59a4484654ea8eb183fea5ae4eb6a41d7ac3e3bae5f4d2a282a3a7d3ca"
 dependencies = [
 "async-trait",
- "futures-core",
+ "futures",
+ "futures-util",
 "http",
+ "opentelemetry",
 "opentelemetry-http",
 "opentelemetry-proto",
- "opentelemetry-semantic-conventions",
- "opentelemetry_api",
- "opentelemetry_sdk",
 "prost",
 "reqwest",
 "thiserror",
- "tokio",
- "tonic",
 ]

 [[package]]
 name = "opentelemetry-proto"
-version = "0.3.0"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b1e3f814aa9f8c905d0ee4bde026afd3b2577a97c10e1699912e3e44f0c4cbeb"
+checksum = "045f8eea8c0fa19f7d48e7bc3128a39c2e5c533d5c61298c548dfefc1064474c"
 dependencies = [
- "opentelemetry_api",
- "opentelemetry_sdk",
+ "futures",
+ "futures-util",
+ "opentelemetry",
 "prost",
- "tonic",
+ "tonic 0.8.3",
 ]

 [[package]]
 name = "opentelemetry-semantic-conventions"
-version = "0.12.0"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "73c9f9340ad135068800e7f1b24e9e09ed9e7143f5bf8518ded3d3ec69789269"
+checksum = "24e33428e6bf08c6f7fcea4ddb8e358fab0fe48ab877a87c70c6ebe20f673ce5"
 dependencies = [
 "opentelemetry",
 ]

 [[package]]
 name = "opentelemetry_api"
-version = "0.20.0"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a81f725323db1b1206ca3da8bb19874bbd3f57c3bcd59471bfb04525b265b9b"
+checksum = "ed41783a5bf567688eb38372f2b7a8530f5a607a4b49d38dd7573236c23ca7e2"
 dependencies = [
+ "fnv",
 "futures-channel",
 "futures-util",
 "indexmap 1.9.3",
- "js-sys",
 "once_cell",
 "pin-project-lite",
 "thiserror",
@@ -3173,22 +3181,21 @@ dependencies = [

 [[package]]
 name = "opentelemetry_sdk"
-version = "0.20.0"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa8e705a0612d48139799fcbaba0d4a90f06277153e43dd2bdc16c6f0edd8026"
+checksum = "8b3a2a91fdbfdd4d212c0dcc2ab540de2c2bcbbd90be17de7a7daf8822d010c1"
 dependencies = [
 "async-trait",
 "crossbeam-channel",
+ "dashmap",
+ "fnv",
 "futures-channel",
 "futures-executor",
 "futures-util",
 "once_cell",
 "opentelemetry_api",
- "ordered-float 3.9.2",
 "percent-encoding",
 "rand 0.8.5",
- "regex",
- "serde_json",
 "thiserror",
 "tokio",
 "tokio-stream",
@@ -3203,15 +3210,6 @@ dependencies = [
 "num-traits",
 ]

-[[package]]
-name = "ordered-float"
-version = "3.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f1e1c390732d15f1d48471625cd92d154e66db2c56645e29a9cd26f4699f72dc"
-dependencies = [
- "num-traits",
-]
-
 [[package]]
 name = "ordered-multimap"
 version = "0.7.1"
@@ -3327,7 +3325,7 @@ dependencies = [
 "itertools",
 "md5",
 "metrics",
- "nix 0.27.1",
+ "nix 0.26.2",
 "num-traits",
 "num_cpus",
 "once_cell",
@@ -4341,9 +4339,9 @@ dependencies = [

 [[package]]
 name = "reqwest-tracing"
-version = "0.4.7"
+version = "0.4.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a0152176687dd5cfe7f507ac1cb1a491c679cfe483afd133a7db7aaea818bb3"
+checksum = "1b97ad83c2fc18113346b7158d79732242002427c30f620fa817c1f32901e0a8"
 dependencies = [
 "anyhow",
 "async-trait",
@@ -5033,9 +5031,9 @@ dependencies = [

 [[package]]
 name = "shlex"
-version = "1.3.0"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+checksum = "43b2853a4d09f215c24cc5489c992ce46052d359b5109343cbafbf26bc62f8a3"

 [[package]]
 name = "signal-hook"
@@ -5197,7 +5195,7 @@ dependencies = [
 "prost",
 "tokio",
 "tokio-stream",
- "tonic",
+ "tonic 0.9.2",
 "tonic-build",
 "tracing",
 "utils",
@@ -5417,7 +5415,7 @@ checksum = "7e54bc85fc7faa8bc175c4bab5b92ba8d9a3ce893d0e9f42cc455c8ab16a9e09"
 dependencies = [
 "byteorder",
 "integer-encoding",
- "ordered-float 2.10.1",
+ "ordered-float",
 ]

 [[package]]
@@ -5683,6 +5681,38 @@ dependencies = [
 "winnow",
 ]

+[[package]]
+name = "tonic"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8f219fad3b929bef19b1f86fbc0358d35daed8f2cac972037ac0dc10bbb8d5fb"
+dependencies = [
+ "async-stream",
+ "async-trait",
+ "axum",
+ "base64 0.13.1",
+ "bytes",
+ "futures-core",
+ "futures-util",
+ "h2",
+ "http",
+ "http-body",
+ "hyper",
+ "hyper-timeout",
+ "percent-encoding",
+ "pin-project",
+ "prost",
+ "prost-derive",
+ "tokio",
+ "tokio-stream",
+ "tokio-util",
+ "tower",
+ "tower-layer",
+ "tower-service",
+ "tracing",
+ "tracing-futures",
+]
+
 [[package]]
 name = "tonic"
 version = "0.9.2"
@@ -5826,6 +5856,16 @@ dependencies = [
 "tracing-subscriber",
 ]

+[[package]]
+name = "tracing-futures"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "97d095ae15e245a057c8e8451bab9b3ee1e1f68e9ba2b4fbc18d0ac5237835f2"
+dependencies = [
+ "pin-project",
+ "tracing",
+]
+
 [[package]]
 name = "tracing-log"
 version = "0.1.3"
@@ -5839,9 +5879,9 @@ dependencies = [

 [[package]]
 name = "tracing-opentelemetry"
-version = "0.20.0"
+version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc09e402904a5261e42cf27aea09ccb7d5318c6717a9eec3d8e2e65c56b18f19"
+checksum = "00a39dcf9bfc1742fa4d6215253b33a6e474be78275884c216fc2a06267b3600"
 dependencies = [
 "once_cell",
 "opentelemetry",
@@ -6078,7 +6118,7 @@ dependencies = [
 "hyper",
 "jsonwebtoken",
 "metrics",
- "nix 0.27.1",
+ "nix 0.26.2",
 "once_cell",
 "pin-project-lite",
 "postgres_connection",
@@ -6586,8 +6626,10 @@ dependencies = [
 "clap",
 "clap_builder",
 "crossbeam-utils",
+ "dashmap",
 "either",
 "fail",
+ "futures",
 "futures-channel",
 "futures-core",
 "futures-executor",
@@ -6632,7 +6674,6 @@ dependencies = [
 "tokio-util",
 "toml_datetime",
 "toml_edit",
- "tonic",
 "tower",
 "tracing",
 "tracing-core",
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -99,14 +99,14 @@ libc = "0.2"
 md5 = "0.7.0"
 memoffset = "0.8"
 native-tls = "0.2"
-nix = { version = "0.27", features = ["fs", "process", "socket", "signal", "poll"] }
-notify = "6.0.0"
+nix = "0.26"
+notify = "5.0.0"
 num_cpus = "1.15"
 num-traits = "0.2.15"
 once_cell = "1.13"
-opentelemetry = "0.20.0"
-opentelemetry-otlp = { version = "0.13.0", default_features=false, features = ["http-proto", "trace", "http", "reqwest-client"] }
-opentelemetry-semantic-conventions = "0.12.0"
+opentelemetry = "0.19.0"
+opentelemetry-otlp = { version = "0.12.0", default_features=false, features = ["http-proto", "trace", "http", "reqwest-client"] }
+opentelemetry-semantic-conventions = "0.11.0"
 parking_lot = "0.12"
 parquet = { version = "49.0.0", default-features = false, features = ["zstd"] }
 parquet_derive = "49.0.0"
@@ -118,7 +118,7 @@ rand = "0.8"
 redis = { version = "0.24.0", features = ["tokio-rustls-comp", "keep-alive"] }
 regex = "1.10.2"
 reqwest = { version = "0.11", default-features = false, features = ["rustls-tls"] }
-reqwest-tracing = { version = "0.4.7", features = ["opentelemetry_0_20"] }
+reqwest-tracing = { version = "0.4.0", features = ["opentelemetry_0_19"] }
 reqwest-middleware = "0.2.0"
 reqwest-retry = "0.2.2"
 routerify = "3"
@@ -162,7 +162,7 @@ toml_edit = "0.19"
 tonic = {version = "0.9", features = ["tls", "tls-roots"]}
 tracing = "0.1"
 tracing-error = "0.2.0"
-tracing-opentelemetry = "0.20.0"
+tracing-opentelemetry = "0.19.0"
 tracing-subscriber = { version = "0.3", default_features = false, features = ["smallvec", "fmt", "tracing-log", "std", "env-filter", "json"] }
 url = "2.2"
 uuid = { version = "1.6.1", features = ["v4", "v7", "serde"] }
--- a/Dockerfile.compute-node
+++ b/Dockerfile.compute-node
@@ -143,8 +143,6 @@ RUN wget https://github.com/pgRouting/pgrouting/archive/v3.4.2.tar.gz -O pgrouti
 #########################################################################################
 FROM build-deps AS plv8-build
 COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/
-
-ARG PG_VERSION
 RUN apt update && \
    apt install -y ninja-build python3-dev libncurses5 binutils clang

@@ -619,7 +617,6 @@ RUN wget https://github.com/theory/pg-semver/archive/refs/tags/v0.32.1.tar.gz -O
 FROM build-deps AS pg-embedding-pg-build
 COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/

-ARG PG_VERSION
 ENV PATH "/usr/local/pgsql/bin/:$PATH"
 RUN case "${PG_VERSION}" in \
      "v14" | "v15") \
@@ -782,8 +779,6 @@ RUN wget https://github.com/eulerto/wal2json/archive/refs/tags/wal2json_2_5.tar.
 #
 #########################################################################################
 FROM build-deps AS neon-pg-ext-build
-ARG PG_VERSION
-
 # Public extensions
 COPY --from=postgis-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=postgis-build /sfcgal/* /
--- a/compute_tools/src/compute.rs
+++ b/compute_tools/src/compute.rs
@@ -700,14 +700,13 @@ impl ComputeNode {
        // In this case we need to connect with old `zenith_admin` name
        // and create new user. We cannot simply rename connected user,
        // but we can create a new one and grant it all privileges.
-        let connstr = self.connstr.clone();
-        let mut client = match Client::connect(connstr.as_str(), NoTls) {
+        let mut client = match Client::connect(self.connstr.as_str(), NoTls) {
            Err(e) => {
                info!(
                    "cannot connect to postgres: {}, retrying with `zenith_admin` username",
                    e
                );
-                let mut zenith_admin_connstr = connstr.clone();
+                let mut zenith_admin_connstr = self.connstr.clone();

                zenith_admin_connstr
                    .set_username("zenith_admin")
@@ -720,8 +719,8 @@ impl ComputeNode {
                client.simple_query("GRANT zenith_admin TO cloud_admin")?;
                drop(client);

-                // reconnect with connstring with expected name
-                Client::connect(connstr.as_str(), NoTls)?
+                // reconnect with connsting with expected name
+                Client::connect(self.connstr.as_str(), NoTls)?
            }
            Ok(client) => client,
        };
@@ -735,8 +734,8 @@ impl ComputeNode {
        cleanup_instance(&mut client)?;
        handle_roles(spec, &mut client)?;
        handle_databases(spec, &mut client)?;
-        handle_role_deletions(spec, connstr.as_str(), &mut client)?;
-        handle_grants(spec, &mut client, connstr.as_str())?;
+        handle_role_deletions(spec, self.connstr.as_str(), &mut client)?;
+        handle_grants(spec, &mut client, self.connstr.as_str())?;
        handle_extensions(spec, &mut client)?;
        handle_extension_neon(&mut client)?;
        create_availability_check_data(&mut client)?;
@@ -744,12 +743,6 @@ impl ComputeNode {
        // 'Close' connection
        drop(client);

-        if self.has_feature(ComputeFeature::Migrations) {
-            thread::spawn(move || {
-                let mut client = Client::connect(connstr.as_str(), NoTls)?;
-                handle_migrations(&mut client)
-            });
-        }
        Ok(())
    }

@@ -814,10 +807,6 @@ impl ComputeNode {
            handle_grants(&spec, &mut client, self.connstr.as_str())?;
            handle_extensions(&spec, &mut client)?;
            handle_extension_neon(&mut client)?;
-            // We can skip handle_migrations here because a new migration can only appear
-            // if we have a new version of the compute_ctl binary, which can only happen
-            // if compute got restarted, in which case we'll end up inside of apply_config
-            // instead of reconfigure.
        }

        // 'Close' connection
--- a/compute_tools/src/spec.rs
+++ b/compute_tools/src/spec.rs
@@ -727,79 +727,3 @@ pub fn handle_extension_neon(client: &mut Client) -> Result<()> {

    Ok(())
 }
-
-#[instrument(skip_all)]
-pub fn handle_migrations(client: &mut Client) -> Result<()> {
-    info!("handle migrations");
-
-    // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-    // !BE SURE TO ONLY ADD MIGRATIONS TO THE END OF THIS ARRAY. IF YOU DO NOT, VERY VERY BAD THINGS MAY HAPPEN!
-    // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-
-    let migrations = [
-        "ALTER ROLE neon_superuser BYPASSRLS",
-        r#"
-DO $$
-DECLARE
-    role_name text;
-BEGIN
-    FOR role_name IN SELECT rolname FROM pg_roles WHERE pg_has_role(rolname, 'neon_superuser', 'member')
-    LOOP
-        RAISE NOTICE 'EXECUTING ALTER ROLE % INHERIT', quote_ident(role_name);
-        EXECUTE 'ALTER ROLE ' || quote_ident(role_name) || ' INHERIT';
-    END LOOP;
-
-    FOR role_name IN SELECT rolname FROM pg_roles
-        WHERE
-            NOT pg_has_role(rolname, 'neon_superuser', 'member') AND NOT starts_with(rolname, 'pg_')
-    LOOP
-        RAISE NOTICE 'EXECUTING ALTER ROLE % NOBYPASSRLS', quote_ident(role_name);
-        EXECUTE 'ALTER ROLE ' || quote_ident(role_name) || ' NOBYPASSRLS';
-    END LOOP;
-END $$;
-"#,
-    ];
-
-    let mut query = "CREATE SCHEMA IF NOT EXISTS neon_migration";
-    client.simple_query(query)?;
-
-    query = "CREATE TABLE IF NOT EXISTS neon_migration.migration_id (key INT NOT NULL PRIMARY KEY, id bigint NOT NULL DEFAULT 0)";
-    client.simple_query(query)?;
-
-    query = "INSERT INTO neon_migration.migration_id VALUES (0, 0) ON CONFLICT DO NOTHING";
-    client.simple_query(query)?;
-
-    query = "ALTER SCHEMA neon_migration OWNER TO cloud_admin";
-    client.simple_query(query)?;
-
-    query = "REVOKE ALL ON SCHEMA neon_migration FROM PUBLIC";
-    client.simple_query(query)?;
-
-    query = "SELECT id FROM neon_migration.migration_id";
-    let row = client.query_one(query, &[])?;
-    let mut current_migration: usize = row.get::<&str, i64>("id") as usize;
-    let starting_migration_id = current_migration;
-
-    query = "BEGIN";
-    client.simple_query(query)?;
-
-    while current_migration < migrations.len() {
-        info!("Running migration:\n{}\n", migrations[current_migration]);
-        client.simple_query(migrations[current_migration])?;
-        current_migration += 1;
-    }
-    let setval = format!(
-        "UPDATE neon_migration.migration_id SET id={}",
-        migrations.len()
-    );
-    client.simple_query(&setval)?;
-
-    query = "COMMIT";
-    client.simple_query(query)?;
-
-    info!(
-        "Ran {} migrations",
-        (migrations.len() - starting_migration_id)
-    );
-    Ok(())
-}
--- a/control_plane/attachment_service/src/persistence.rs
+++ b/control_plane/attachment_service/src/persistence.rs
@@ -184,7 +184,7 @@ impl Persistence {
    pub(crate) async fn increment_generation(
        &self,
        tenant_shard_id: TenantShardId,
-        node_id: NodeId,
+        node_id: Option<NodeId>,
    ) -> anyhow::Result<Generation> {
        let (write, gen) = {
            let mut locked = self.state.lock().unwrap();
@@ -192,9 +192,14 @@ impl Persistence {
                anyhow::bail!("Tried to increment generation of unknown shard");
            };

-            shard.generation += 1;
-            shard.generation_pageserver = Some(node_id);
+            // If we're called with a None pageserver, we need only update the generation
+            // record to disassociate it with this pageserver, not actually increment the number, as
+            // the increment is guaranteed to happen the next time this tenant is attached.
+            if node_id.is_some() {
+                shard.generation += 1;
+            }

+            shard.generation_pageserver = node_id;
            let gen = Generation::new(shard.generation);
            (locked.save(), gen)
        };
@@ -203,19 +208,6 @@ impl Persistence {
        Ok(gen)
    }

-    pub(crate) async fn detach(&self, tenant_shard_id: TenantShardId) -> anyhow::Result<()> {
-        let write = {
-            let mut locked = self.state.lock().unwrap();
-            let Some(shard) = locked.tenants.get_mut(&tenant_shard_id) else {
-                anyhow::bail!("Tried to increment generation of unknown shard");
-            };
-            shard.generation_pageserver = None;
-            locked.save()
-        };
-        write.commit().await?;
-        Ok(())
-    }
-
    pub(crate) async fn re_attach(
        &self,
        node_id: NodeId,
--- a/control_plane/attachment_service/src/reconciler.rs
+++ b/control_plane/attachment_service/src/reconciler.rs
@@ -296,7 +296,7 @@ impl Reconciler {
        // Increment generation before attaching to new pageserver
        self.generation = self
            .persistence
-            .increment_generation(self.tenant_shard_id, dest_ps_id)
+            .increment_generation(self.tenant_shard_id, Some(dest_ps_id))
            .await?;

        let dest_conf = build_location_config(
@@ -395,7 +395,7 @@ impl Reconciler {
                    // as locations with unknown (None) observed state.
                    self.generation = self
                        .persistence
-                        .increment_generation(self.tenant_shard_id, node_id)
+                        .increment_generation(self.tenant_shard_id, Some(node_id))
                        .await?;
                    wanted_conf.generation = self.generation.into();
                    tracing::info!("Observed configuration requires update.");
--- a/control_plane/attachment_service/src/service.rs
+++ b/control_plane/attachment_service/src/service.rs
@@ -362,14 +362,13 @@ impl Service {
            );
        }

-        let new_generation = if let Some(req_node_id) = attach_req.node_id {
+        let new_generation = if attach_req.node_id.is_some() {
            Some(
                self.persistence
-                    .increment_generation(attach_req.tenant_shard_id, req_node_id)
+                    .increment_generation(attach_req.tenant_shard_id, attach_req.node_id)
                    .await?,
            )
        } else {
-            self.persistence.detach(attach_req.tenant_shard_id).await?;
            None
        };

@@ -408,7 +407,6 @@ impl Service {
            "attach_hook: tenant {} set generation {:?}, pageserver {}",
            attach_req.tenant_shard_id,
            tenant_state.generation,
-            // TODO: this is an odd number of 0xf's
            attach_req.node_id.unwrap_or(utils::id::NodeId(0xfffffff))
        );

--- a/control_plane/src/endpoint.rs
+++ b/control_plane/src/endpoint.rs
@@ -57,7 +57,7 @@ use crate::local_env::LocalEnv;
 use crate::postgresql_conf::PostgresConf;

 use compute_api::responses::{ComputeState, ComputeStatus};
-use compute_api::spec::{Cluster, ComputeFeature, ComputeMode, ComputeSpec};
+use compute_api::spec::{Cluster, ComputeMode, ComputeSpec};

 // contents of a endpoint.json file
 #[derive(Serialize, Deserialize, PartialEq, Eq, Clone, Debug)]
@@ -70,7 +70,6 @@ pub struct EndpointConf {
    http_port: u16,
    pg_version: u32,
    skip_pg_catalog_updates: bool,
-    features: Vec<ComputeFeature>,
 }

 //
@@ -141,7 +140,6 @@ impl ComputeControlPlane {
            // with this we basically test a case of waking up an idle compute, where
            // we also skip catalog updates in the cloud.
            skip_pg_catalog_updates: true,
-            features: vec![],
        });

        ep.create_endpoint_dir()?;
@@ -156,7 +154,6 @@ impl ComputeControlPlane {
                pg_port,
                pg_version,
                skip_pg_catalog_updates: true,
-                features: vec![],
            })?,
        )?;
        std::fs::write(
@@ -218,9 +215,6 @@ pub struct Endpoint {

    // Optimizations
    skip_pg_catalog_updates: bool,
-
-    // Feature flags
-    features: Vec<ComputeFeature>,
 }

 impl Endpoint {
@@ -250,7 +244,6 @@ impl Endpoint {
            tenant_id: conf.tenant_id,
            pg_version: conf.pg_version,
            skip_pg_catalog_updates: conf.skip_pg_catalog_updates,
-            features: conf.features,
        })
    }

@@ -526,7 +519,7 @@ impl Endpoint {
            skip_pg_catalog_updates: self.skip_pg_catalog_updates,
            format_version: 1.0,
            operation_uuid: None,
-            features: self.features.clone(),
+            features: vec![],
            cluster: Cluster {
                cluster_id: None, // project ID: not used
                name: None,       // project name: not used
--- a/libs/compute_api/src/spec.rs
+++ b/libs/compute_api/src/spec.rs
@@ -90,9 +90,6 @@ pub enum ComputeFeature {
    /// track short-lived connections as user activity.
    ActivityMonitorExperimental,

-    /// Enable running migrations
-    Migrations,
-
    /// This is a special feature flag that is used to represent unknown feature flags.
    /// Basically all unknown to enum flags are represented as this one. See unit test
    /// `parse_unknown_features()` for more details.
--- a/libs/pageserver_api/src/key.rs
+++ b/libs/pageserver_api/src/key.rs
@@ -1,11 +1,9 @@
 use anyhow::{bail, Result};
 use byteorder::{ByteOrder, BE};
-use postgres_ffi::relfile_utils::{FSM_FORKNUM, VISIBILITYMAP_FORKNUM};
-use postgres_ffi::{Oid, TransactionId};
 use serde::{Deserialize, Serialize};
-use std::{fmt, ops::Range};
+use std::fmt;

-use crate::reltag::{BlockNumber, RelTag, SlruKind};
+use crate::reltag::{BlockNumber, RelTag};

 /// Key used in the Repository kv-store.
 ///
@@ -145,390 +143,12 @@ impl Key {
    }
 }

-// Layout of the Key address space
-//
-// The Key struct, used to address the underlying key-value store, consists of
-// 18 bytes, split into six fields. See 'Key' in repository.rs. We need to map
-// all the data and metadata keys into those 18 bytes.
-//
-// Principles for the mapping:
-//
-// - Things that are often accessed or modified together, should be close to
-//   each other in the key space. For example, if a relation is extended by one
-//   block, we create a new key-value pair for the block data, and update the
-//   relation size entry. Because of that, the RelSize key comes after all the
-//   RelBlocks of a relation: the RelSize and the last RelBlock are always next
-//   to each other.
-//
-// The key space is divided into four major sections, identified by the first
-// byte, and the form a hierarchy:
-//
-// 00 Relation data and metadata
-//
-//   DbDir    () -> (dbnode, spcnode)
-//   Filenodemap
-//   RelDir   -> relnode forknum
-//       RelBlocks
-//       RelSize
-//
-// 01 SLRUs
-//
-//   SlruDir  kind
-//   SlruSegBlocks segno
-//   SlruSegSize
-//
-// 02 pg_twophase
-//
-// 03 misc
-//    Controlfile
-//    checkpoint
-//    pg_version
-//
-// 04 aux files
-//
-// Below is a full list of the keyspace allocation:
-//
-// DbDir:
-// 00 00000000 00000000 00000000 00   00000000
-//
-// Filenodemap:
-// 00 SPCNODE  DBNODE   00000000 00   00000000
-//
-// RelDir:
-// 00 SPCNODE  DBNODE   00000000 00   00000001 (Postgres never uses relfilenode 0)
-//
-// RelBlock:
-// 00 SPCNODE  DBNODE   RELNODE  FORK BLKNUM
-//
-// RelSize:
-// 00 SPCNODE  DBNODE   RELNODE  FORK FFFFFFFF
-//
-// SlruDir:
-// 01 kind     00000000 00000000 00   00000000
-//
-// SlruSegBlock:
-// 01 kind     00000001 SEGNO    00   BLKNUM
-//
-// SlruSegSize:
-// 01 kind     00000001 SEGNO    00   FFFFFFFF
-//
-// TwoPhaseDir:
-// 02 00000000 00000000 00000000 00   00000000
-//
-// TwoPhaseFile:
-// 02 00000000 00000000 00000000 00   XID
-//
-// ControlFile:
-// 03 00000000 00000000 00000000 00   00000000
-//
-// Checkpoint:
-// 03 00000000 00000000 00000000 00   00000001
-//
-// AuxFiles:
-// 03 00000000 00000000 00000000 00   00000002
-//
-
-//-- Section 01: relation data and metadata
-
-pub const DBDIR_KEY: Key = Key {
-    field1: 0x00,
-    field2: 0,
-    field3: 0,
-    field4: 0,
-    field5: 0,
-    field6: 0,
-};
-
-#[inline(always)]
-pub fn dbdir_key_range(spcnode: Oid, dbnode: Oid) -> Range<Key> {
-    Key {
-        field1: 0x00,
-        field2: spcnode,
-        field3: dbnode,
-        field4: 0,
-        field5: 0,
-        field6: 0,
-    }..Key {
-        field1: 0x00,
-        field2: spcnode,
-        field3: dbnode,
-        field4: 0xffffffff,
-        field5: 0xff,
-        field6: 0xffffffff,
-    }
-}
-
-#[inline(always)]
-pub fn relmap_file_key(spcnode: Oid, dbnode: Oid) -> Key {
-    Key {
-        field1: 0x00,
-        field2: spcnode,
-        field3: dbnode,
-        field4: 0,
-        field5: 0,
-        field6: 0,
-    }
-}
-
-#[inline(always)]
-pub fn rel_dir_to_key(spcnode: Oid, dbnode: Oid) -> Key {
-    Key {
-        field1: 0x00,
-        field2: spcnode,
-        field3: dbnode,
-        field4: 0,
-        field5: 0,
-        field6: 1,
-    }
-}
-
-#[inline(always)]
-pub fn rel_block_to_key(rel: RelTag, blknum: BlockNumber) -> Key {
-    Key {
-        field1: 0x00,
-        field2: rel.spcnode,
-        field3: rel.dbnode,
-        field4: rel.relnode,
-        field5: rel.forknum,
-        field6: blknum,
-    }
-}
-
-#[inline(always)]
-pub fn rel_size_to_key(rel: RelTag) -> Key {
-    Key {
-        field1: 0x00,
-        field2: rel.spcnode,
-        field3: rel.dbnode,
-        field4: rel.relnode,
-        field5: rel.forknum,
-        field6: 0xffffffff,
-    }
-}
-
-#[inline(always)]
-pub fn rel_key_range(rel: RelTag) -> Range<Key> {
-    Key {
-        field1: 0x00,
-        field2: rel.spcnode,
-        field3: rel.dbnode,
-        field4: rel.relnode,
-        field5: rel.forknum,
-        field6: 0,
-    }..Key {
-        field1: 0x00,
-        field2: rel.spcnode,
-        field3: rel.dbnode,
-        field4: rel.relnode,
-        field5: rel.forknum + 1,
-        field6: 0,
-    }
-}
-
-//-- Section 02: SLRUs
-
-#[inline(always)]
-pub fn slru_dir_to_key(kind: SlruKind) -> Key {
-    Key {
-        field1: 0x01,
-        field2: match kind {
-            SlruKind::Clog => 0x00,
-            SlruKind::MultiXactMembers => 0x01,
-            SlruKind::MultiXactOffsets => 0x02,
-        },
-        field3: 0,
-        field4: 0,
-        field5: 0,
-        field6: 0,
-    }
-}
-
-#[inline(always)]
-pub fn slru_block_to_key(kind: SlruKind, segno: u32, blknum: BlockNumber) -> Key {
-    Key {
-        field1: 0x01,
-        field2: match kind {
-            SlruKind::Clog => 0x00,
-            SlruKind::MultiXactMembers => 0x01,
-            SlruKind::MultiXactOffsets => 0x02,
-        },
-        field3: 1,
-        field4: segno,
-        field5: 0,
-        field6: blknum,
-    }
-}
-
-#[inline(always)]
-pub fn slru_segment_size_to_key(kind: SlruKind, segno: u32) -> Key {
-    Key {
-        field1: 0x01,
-        field2: match kind {
-            SlruKind::Clog => 0x00,
-            SlruKind::MultiXactMembers => 0x01,
-            SlruKind::MultiXactOffsets => 0x02,
-        },
-        field3: 1,
-        field4: segno,
-        field5: 0,
-        field6: 0xffffffff,
-    }
-}
-
-#[inline(always)]
-pub fn slru_segment_key_range(kind: SlruKind, segno: u32) -> Range<Key> {
-    let field2 = match kind {
-        SlruKind::Clog => 0x00,
-        SlruKind::MultiXactMembers => 0x01,
-        SlruKind::MultiXactOffsets => 0x02,
-    };
-
-    Key {
-        field1: 0x01,
-        field2,
-        field3: 1,
-        field4: segno,
-        field5: 0,
-        field6: 0,
-    }..Key {
-        field1: 0x01,
-        field2,
-        field3: 1,
-        field4: segno,
-        field5: 1,
-        field6: 0,
-    }
-}
-
-//-- Section 03: pg_twophase
-
-pub const TWOPHASEDIR_KEY: Key = Key {
-    field1: 0x02,
-    field2: 0,
-    field3: 0,
-    field4: 0,
-    field5: 0,
-    field6: 0,
-};
-
-#[inline(always)]
-pub fn twophase_file_key(xid: TransactionId) -> Key {
-    Key {
-        field1: 0x02,
-        field2: 0,
-        field3: 0,
-        field4: 0,
-        field5: 0,
-        field6: xid,
-    }
-}
-
-#[inline(always)]
-pub fn twophase_key_range(xid: TransactionId) -> Range<Key> {
-    let (next_xid, overflowed) = xid.overflowing_add(1);
-
-    Key {
-        field1: 0x02,
-        field2: 0,
-        field3: 0,
-        field4: 0,
-        field5: 0,
-        field6: xid,
-    }..Key {
-        field1: 0x02,
-        field2: 0,
-        field3: 0,
-        field4: 0,
-        field5: u8::from(overflowed),
-        field6: next_xid,
-    }
-}
-
-//-- Section 03: Control file
-pub const CONTROLFILE_KEY: Key = Key {
-    field1: 0x03,
-    field2: 0,
-    field3: 0,
-    field4: 0,
-    field5: 0,
-    field6: 0,
-};
-
-pub const CHECKPOINT_KEY: Key = Key {
-    field1: 0x03,
-    field2: 0,
-    field3: 0,
-    field4: 0,
-    field5: 0,
-    field6: 1,
-};
-
-pub 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.
-
-// AUX_FILES currently stores only data for logical replication (slots etc), and
-// we don't preserve these on a branch because safekeepers can't follow timeline
-// switch (and generally it likely should be optional), so ignore these.
-#[inline(always)]
-pub fn is_inherited_key(key: Key) -> bool {
-    key != AUX_FILES_KEY
-}
-
-#[inline(always)]
-pub fn is_rel_fsm_block_key(key: Key) -> bool {
-    key.field1 == 0x00 && key.field4 != 0 && key.field5 == FSM_FORKNUM && key.field6 != 0xffffffff
-}
-
-#[inline(always)]
-pub fn is_rel_vm_block_key(key: Key) -> bool {
-    key.field1 == 0x00
-        && key.field4 != 0
-        && key.field5 == VISIBILITYMAP_FORKNUM
-        && key.field6 != 0xffffffff
-}
-
-#[inline(always)]
-pub fn key_to_slru_block(key: Key) -> anyhow::Result<(SlruKind, u32, BlockNumber)> {
-    Ok(match key.field1 {
-        0x01 => {
-            let kind = match key.field2 {
-                0x00 => SlruKind::Clog,
-                0x01 => SlruKind::MultiXactMembers,
-                0x02 => SlruKind::MultiXactOffsets,
-                _ => anyhow::bail!("unrecognized slru kind 0x{:02x}", key.field2),
-            };
-            let segno = key.field4;
-            let blknum = key.field6;
-
-            (kind, segno, blknum)
-        }
-        _ => anyhow::bail!("unexpected value kind 0x{:02x}", key.field1),
-    })
-}
-
-#[inline(always)]
-pub fn is_slru_block_key(key: Key) -> bool {
-    key.field1 == 0x01                // SLRU-related
-        && key.field3 == 0x00000001   // but not SlruDir
-        && key.field6 != 0xffffffff // and not SlruSegSize
-}
-
 #[inline(always)]
 pub fn is_rel_block_key(key: &Key) -> bool {
    key.field1 == 0x00 && key.field4 != 0 && key.field6 != 0xffffffff
 }

 /// Guaranteed to return `Ok()` if [[is_rel_block_key]] returns `true` for `key`.
-#[inline(always)]
 pub fn key_to_rel_block(key: Key) -> anyhow::Result<(RelTag, BlockNumber)> {
    Ok(match key.field1 {
        0x00 => (
--- a/libs/postgres_ffi/src/xlog_utils.rs
+++ b/libs/postgres_ffi/src/xlog_utils.rs
@@ -329,8 +329,8 @@ impl CheckPoint {
    ///
    /// Returns 'true' if the XID was updated.
    pub fn update_next_xid(&mut self, xid: u32) -> bool {
-        // nextXid should be greater than any XID in WAL, so increment provided XID and check for wraparround.
-        let mut new_xid = std::cmp::max(xid.wrapping_add(1), pg_constants::FIRST_NORMAL_TRANSACTION_ID);
+        // nextXid should nw greater than any XID in WAL, so increment provided XID and check for wraparround.
+        let mut new_xid = std::cmp::max(xid + 1, pg_constants::FIRST_NORMAL_TRANSACTION_ID);
        // To reduce number of metadata checkpoints, we forward align XID on XID_CHECKPOINT_INTERVAL.
        // XID_CHECKPOINT_INTERVAL should not be larger than BLCKSZ*CLOG_XACTS_PER_BYTE
        new_xid =
--- a/libs/pq_proto/src/framed.rs
+++ b/libs/pq_proto/src/framed.rs
@@ -82,19 +82,6 @@ impl<S> Framed<S> {
            write_buf: self.write_buf,
        })
    }
-
-    /// Return new Framed with stream type transformed by f. For dynamic dispatch.
-    pub fn map_stream_sync<S2, F>(self, f: F) -> Framed<S2>
-    where
-        F: FnOnce(S) -> S2,
-    {
-        let stream = f(self.stream);
-        Framed {
-            stream,
-            read_buf: self.read_buf,
-            write_buf: self.write_buf,
-        }
-    }
 }

 impl<S: AsyncRead + Unpin> Framed<S> {
--- a/libs/utils/src/nonblock.rs
+++ b/libs/utils/src/nonblock.rs
@@ -5,10 +5,10 @@ use std::os::unix::io::RawFd;
 pub fn set_nonblock(fd: RawFd) -> Result<(), std::io::Error> {
    let bits = fcntl(fd, F_GETFL)?;

-    // If F_GETFL returns some unknown bits, they should be valid
+    // Safety: If F_GETFL returns some unknown bits, they should be valid
    // for passing back to F_SETFL, too. If we left them out, the F_SETFL
    // would effectively clear them, which is not what we want.
-    let mut flags = OFlag::from_bits_retain(bits);
+    let mut flags = unsafe { OFlag::from_bits_unchecked(bits) };
    flags |= OFlag::O_NONBLOCK;

    fcntl(fd, F_SETFL(flags))?;
--- a/libs/utils/src/tcp_listener.rs
+++ b/libs/utils/src/tcp_listener.rs
@@ -1,6 +1,7 @@
 use std::{
    io,
    net::{TcpListener, ToSocketAddrs},
+    os::unix::prelude::AsRawFd,
 };

 use nix::sys::socket::{setsockopt, sockopt::ReuseAddr};
@@ -9,7 +10,7 @@ use nix::sys::socket::{setsockopt, sockopt::ReuseAddr};
 pub fn bind<A: ToSocketAddrs>(addr: A) -> io::Result<TcpListener> {
    let listener = TcpListener::bind(addr)?;

-    setsockopt(&listener, ReuseAddr, &true)?;
+    setsockopt(listener.as_raw_fd(), ReuseAddr, &true)?;

    Ok(listener)
 }
--- a/pageserver/src/page_service.rs
+++ b/pageserver/src/page_service.rs
@@ -61,7 +61,7 @@ use crate::context::{DownloadBehavior, RequestContext};
 use crate::import_datadir::import_wal_from_tar;
 use crate::metrics;
 use crate::metrics::LIVE_CONNECTIONS_COUNT;
-use crate::pgdatadir_mapping::Version;
+use crate::pgdatadir_mapping::{rel_block_to_key, Version};
 use crate::task_mgr;
 use crate::task_mgr::TaskKind;
 use crate::tenant::debug_assert_current_span_has_tenant_and_timeline_id;
@@ -75,7 +75,6 @@ use crate::tenant::PageReconstructError;
 use crate::tenant::Timeline;
 use crate::trace::Tracer;

-use pageserver_api::key::rel_block_to_key;
 use postgres_ffi::pg_constants::DEFAULTTABLESPACE_OID;
 use postgres_ffi::BLCKSZ;

@@ -387,18 +386,12 @@ impl PageServerHandler {

    /// Future that completes when we need to shut down the connection.
    ///
-    /// We currently need to shut down when any of the following happens:
-    /// 1. any of the timelines we hold GateGuards for in `shard_timelines` is cancelled
-    /// 2. task_mgr requests shutdown of the connection
+    /// Reasons for need to shut down are:
+    /// - any of the timelines we hold GateGuards for in `shard_timelines` is cancelled
+    /// - task_mgr requests shutdown of the connection
    ///
-    /// NB on (1): the connection's lifecycle is not actually tied to any of the
-    /// `shard_timelines`s' lifecycles. But it's _necessary_ in the current
-    /// implementation to be responsive to timeline cancellation because
-    /// the connection holds their `GateGuards` open (sored in `shard_timelines`).
-    /// We currently do the easy thing and terminate the connection if any of the
-    /// shard_timelines gets cancelled. But really, we cuold spend more effort
-    /// and simply remove the cancelled timeline from the `shard_timelines`, thereby
-    /// dropping the guard.
+    /// The need to check for `task_mgr` cancellation arises mainly from `handle_pagerequests`
+    /// where, at first, `shard_timelines` is empty, see <https://github.com/neondatabase/neon/pull/6388>
    ///
    /// NB: keep in sync with [`Self::is_connection_cancelled`]
    async fn await_connection_cancelled(&self) {
@@ -411,17 +404,16 @@ impl PageServerHandler {
        // immutable &self).  So it's fine to evaluate shard_timelines after the sleep, we don't risk
        // missing any inserts to the map.

-        let mut cancellation_sources = Vec::with_capacity(1 + self.shard_timelines.len());
-        use futures::future::Either;
-        cancellation_sources.push(Either::Left(task_mgr::shutdown_watcher()));
-        cancellation_sources.extend(
-            self.shard_timelines
-                .values()
-                .map(|ht| Either::Right(ht.timeline.cancel.cancelled())),
-        );
-        FuturesUnordered::from_iter(cancellation_sources)
-            .next()
-            .await;
+        let mut futs = self
+            .shard_timelines
+            .values()
+            .map(|ht| ht.timeline.cancel.cancelled())
+            .collect::<FuturesUnordered<_>>();
+
+        tokio::select! {
+            _ = task_mgr::shutdown_watcher() => { }
+            _ = futs.next() => {}
+        }
    }

    /// Checking variant of [`Self::await_connection_cancelled`].
--- a/pageserver/src/pgdatadir_mapping.rs
+++ b/pageserver/src/pgdatadir_mapping.rs
@@ -13,12 +13,7 @@ use crate::repository::*;
 use crate::walrecord::NeonWalRecord;
 use anyhow::{ensure, Context};
 use bytes::{Buf, Bytes};
-use pageserver_api::key::{
-    dbdir_key_range, is_rel_block_key, is_slru_block_key, rel_block_to_key, rel_dir_to_key,
-    rel_key_range, rel_size_to_key, relmap_file_key, slru_block_to_key, slru_dir_to_key,
-    slru_segment_key_range, slru_segment_size_to_key, twophase_file_key, twophase_key_range,
-    AUX_FILES_KEY, CHECKPOINT_KEY, CONTROLFILE_KEY, DBDIR_KEY, TWOPHASEDIR_KEY,
-};
+use pageserver_api::key::is_rel_block_key;
 use pageserver_api::reltag::{BlockNumber, RelTag, SlruKind};
 use postgres_ffi::relfile_utils::{FSM_FORKNUM, VISIBILITYMAP_FORKNUM};
 use postgres_ffi::BLCKSZ;
@@ -1540,6 +1535,366 @@ struct SlruSegmentDirectory {

 static ZERO_PAGE: Bytes = Bytes::from_static(&[0u8; BLCKSZ as usize]);

+// Layout of the Key address space
+//
+// The Key struct, used to address the underlying key-value store, consists of
+// 18 bytes, split into six fields. See 'Key' in repository.rs. We need to map
+// all the data and metadata keys into those 18 bytes.
+//
+// Principles for the mapping:
+//
+// - Things that are often accessed or modified together, should be close to
+//   each other in the key space. For example, if a relation is extended by one
+//   block, we create a new key-value pair for the block data, and update the
+//   relation size entry. Because of that, the RelSize key comes after all the
+//   RelBlocks of a relation: the RelSize and the last RelBlock are always next
+//   to each other.
+//
+// The key space is divided into four major sections, identified by the first
+// byte, and the form a hierarchy:
+//
+// 00 Relation data and metadata
+//
+//   DbDir    () -> (dbnode, spcnode)
+//   Filenodemap
+//   RelDir   -> relnode forknum
+//       RelBlocks
+//       RelSize
+//
+// 01 SLRUs
+//
+//   SlruDir  kind
+//   SlruSegBlocks segno
+//   SlruSegSize
+//
+// 02 pg_twophase
+//
+// 03 misc
+//    Controlfile
+//    checkpoint
+//    pg_version
+//
+// 04 aux files
+//
+// Below is a full list of the keyspace allocation:
+//
+// DbDir:
+// 00 00000000 00000000 00000000 00   00000000
+//
+// Filenodemap:
+// 00 SPCNODE  DBNODE   00000000 00   00000000
+//
+// RelDir:
+// 00 SPCNODE  DBNODE   00000000 00   00000001 (Postgres never uses relfilenode 0)
+//
+// RelBlock:
+// 00 SPCNODE  DBNODE   RELNODE  FORK BLKNUM
+//
+// RelSize:
+// 00 SPCNODE  DBNODE   RELNODE  FORK FFFFFFFF
+//
+// SlruDir:
+// 01 kind     00000000 00000000 00   00000000
+//
+// SlruSegBlock:
+// 01 kind     00000001 SEGNO    00   BLKNUM
+//
+// SlruSegSize:
+// 01 kind     00000001 SEGNO    00   FFFFFFFF
+//
+// TwoPhaseDir:
+// 02 00000000 00000000 00000000 00   00000000
+//
+// TwoPhaseFile:
+// 02 00000000 00000000 00000000 00   XID
+//
+// ControlFile:
+// 03 00000000 00000000 00000000 00   00000000
+//
+// 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 {
+    field1: 0x00,
+    field2: 0,
+    field3: 0,
+    field4: 0,
+    field5: 0,
+    field6: 0,
+};
+
+fn dbdir_key_range(spcnode: Oid, dbnode: Oid) -> Range<Key> {
+    Key {
+        field1: 0x00,
+        field2: spcnode,
+        field3: dbnode,
+        field4: 0,
+        field5: 0,
+        field6: 0,
+    }..Key {
+        field1: 0x00,
+        field2: spcnode,
+        field3: dbnode,
+        field4: 0xffffffff,
+        field5: 0xff,
+        field6: 0xffffffff,
+    }
+}
+
+fn relmap_file_key(spcnode: Oid, dbnode: Oid) -> Key {
+    Key {
+        field1: 0x00,
+        field2: spcnode,
+        field3: dbnode,
+        field4: 0,
+        field5: 0,
+        field6: 0,
+    }
+}
+
+fn rel_dir_to_key(spcnode: Oid, dbnode: Oid) -> Key {
+    Key {
+        field1: 0x00,
+        field2: spcnode,
+        field3: dbnode,
+        field4: 0,
+        field5: 0,
+        field6: 1,
+    }
+}
+
+pub(crate) fn rel_block_to_key(rel: RelTag, blknum: BlockNumber) -> Key {
+    Key {
+        field1: 0x00,
+        field2: rel.spcnode,
+        field3: rel.dbnode,
+        field4: rel.relnode,
+        field5: rel.forknum,
+        field6: blknum,
+    }
+}
+
+fn rel_size_to_key(rel: RelTag) -> Key {
+    Key {
+        field1: 0x00,
+        field2: rel.spcnode,
+        field3: rel.dbnode,
+        field4: rel.relnode,
+        field5: rel.forknum,
+        field6: 0xffffffff,
+    }
+}
+
+fn rel_key_range(rel: RelTag) -> Range<Key> {
+    Key {
+        field1: 0x00,
+        field2: rel.spcnode,
+        field3: rel.dbnode,
+        field4: rel.relnode,
+        field5: rel.forknum,
+        field6: 0,
+    }..Key {
+        field1: 0x00,
+        field2: rel.spcnode,
+        field3: rel.dbnode,
+        field4: rel.relnode,
+        field5: rel.forknum + 1,
+        field6: 0,
+    }
+}
+
+//-- Section 02: SLRUs
+
+fn slru_dir_to_key(kind: SlruKind) -> Key {
+    Key {
+        field1: 0x01,
+        field2: match kind {
+            SlruKind::Clog => 0x00,
+            SlruKind::MultiXactMembers => 0x01,
+            SlruKind::MultiXactOffsets => 0x02,
+        },
+        field3: 0,
+        field4: 0,
+        field5: 0,
+        field6: 0,
+    }
+}
+
+fn slru_block_to_key(kind: SlruKind, segno: u32, blknum: BlockNumber) -> Key {
+    Key {
+        field1: 0x01,
+        field2: match kind {
+            SlruKind::Clog => 0x00,
+            SlruKind::MultiXactMembers => 0x01,
+            SlruKind::MultiXactOffsets => 0x02,
+        },
+        field3: 1,
+        field4: segno,
+        field5: 0,
+        field6: blknum,
+    }
+}
+
+fn slru_segment_size_to_key(kind: SlruKind, segno: u32) -> Key {
+    Key {
+        field1: 0x01,
+        field2: match kind {
+            SlruKind::Clog => 0x00,
+            SlruKind::MultiXactMembers => 0x01,
+            SlruKind::MultiXactOffsets => 0x02,
+        },
+        field3: 1,
+        field4: segno,
+        field5: 0,
+        field6: 0xffffffff,
+    }
+}
+
+fn slru_segment_key_range(kind: SlruKind, segno: u32) -> Range<Key> {
+    let field2 = match kind {
+        SlruKind::Clog => 0x00,
+        SlruKind::MultiXactMembers => 0x01,
+        SlruKind::MultiXactOffsets => 0x02,
+    };
+
+    Key {
+        field1: 0x01,
+        field2,
+        field3: 1,
+        field4: segno,
+        field5: 0,
+        field6: 0,
+    }..Key {
+        field1: 0x01,
+        field2,
+        field3: 1,
+        field4: segno,
+        field5: 1,
+        field6: 0,
+    }
+}
+
+//-- Section 03: pg_twophase
+
+const TWOPHASEDIR_KEY: Key = Key {
+    field1: 0x02,
+    field2: 0,
+    field3: 0,
+    field4: 0,
+    field5: 0,
+    field6: 0,
+};
+
+fn twophase_file_key(xid: TransactionId) -> Key {
+    Key {
+        field1: 0x02,
+        field2: 0,
+        field3: 0,
+        field4: 0,
+        field5: 0,
+        field6: xid,
+    }
+}
+
+fn twophase_key_range(xid: TransactionId) -> Range<Key> {
+    let (next_xid, overflowed) = xid.overflowing_add(1);
+
+    Key {
+        field1: 0x02,
+        field2: 0,
+        field3: 0,
+        field4: 0,
+        field5: 0,
+        field6: xid,
+    }..Key {
+        field1: 0x02,
+        field2: 0,
+        field3: 0,
+        field4: 0,
+        field5: u8::from(overflowed),
+        field6: next_xid,
+    }
+}
+
+//-- Section 03: Control file
+const CONTROLFILE_KEY: Key = Key {
+    field1: 0x03,
+    field2: 0,
+    field3: 0,
+    field4: 0,
+    field5: 0,
+    field6: 0,
+};
+
+const CHECKPOINT_KEY: Key = Key {
+    field1: 0x03,
+    field2: 0,
+    field3: 0,
+    field4: 0,
+    field5: 0,
+    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.
+
+// AUX_FILES currently stores only data for logical replication (slots etc), and
+// we don't preserve these on a branch because safekeepers can't follow timeline
+// switch (and generally it likely should be optional), so ignore these.
+pub fn is_inherited_key(key: Key) -> bool {
+    key != AUX_FILES_KEY
+}
+
+pub fn is_rel_fsm_block_key(key: Key) -> bool {
+    key.field1 == 0x00 && key.field4 != 0 && key.field5 == FSM_FORKNUM && key.field6 != 0xffffffff
+}
+
+pub fn is_rel_vm_block_key(key: Key) -> bool {
+    key.field1 == 0x00
+        && key.field4 != 0
+        && key.field5 == VISIBILITYMAP_FORKNUM
+        && key.field6 != 0xffffffff
+}
+
+pub fn key_to_slru_block(key: Key) -> anyhow::Result<(SlruKind, u32, BlockNumber)> {
+    Ok(match key.field1 {
+        0x01 => {
+            let kind = match key.field2 {
+                0x00 => SlruKind::Clog,
+                0x01 => SlruKind::MultiXactMembers,
+                0x02 => SlruKind::MultiXactOffsets,
+                _ => anyhow::bail!("unrecognized slru kind 0x{:02x}", key.field2),
+            };
+            let segno = key.field4;
+            let blknum = key.field6;
+
+            (kind, segno, blknum)
+        }
+        _ => anyhow::bail!("unexpected value kind 0x{:02x}", key.field1),
+    })
+}
+
+fn is_slru_block_key(key: Key) -> bool {
+    key.field1 == 0x01                // SLRU-related
+        && key.field3 == 0x00000001   // but not SlruDir
+        && key.field6 != 0xffffffff // and not SlruSegSize
+}
+
 #[allow(clippy::bool_assert_comparison)]
 #[cfg(test)]
 mod tests {
--- a/pageserver/src/tenant.rs
+++ b/pageserver/src/tenant.rs
@@ -716,10 +716,6 @@ impl Tenant {
                            // stayed in Activating for such a long time that shutdown found it in
                            // that state.
                            tracing::info!(state=%tenant_clone.current_state(), "Tenant shut down before activation");
-                            // Make the tenant broken so that set_stopping will not hang waiting for it to leave
-                            // the Attaching state.  This is an over-reaction (nothing really broke, the tenant is
-                            // just shutting down), but ensures progress.
-                            make_broken(&tenant_clone, anyhow::anyhow!("Shut down while Attaching"));
                            return Ok(());
                        },
                    )
--- a/pageserver/src/tenant/timeline.rs
+++ b/pageserver/src/tenant/timeline.rs
@@ -73,8 +73,8 @@ use crate::metrics::{
    TimelineMetrics, MATERIALIZED_PAGE_CACHE_HIT, MATERIALIZED_PAGE_CACHE_HIT_DIRECT,
 };
 use crate::pgdatadir_mapping::CalculateLogicalSizeError;
+use crate::pgdatadir_mapping::{is_inherited_key, is_rel_fsm_block_key, is_rel_vm_block_key};
 use crate::tenant::config::TenantConfOpt;
-use pageserver_api::key::{is_inherited_key, is_rel_fsm_block_key, is_rel_vm_block_key};
 use pageserver_api::reltag::RelTag;
 use pageserver_api::shard::ShardIndex;

--- a/pageserver/src/walingest.rs
+++ b/pageserver/src/walingest.rs
@@ -33,12 +33,11 @@ use utils::failpoint_support;

 use crate::context::RequestContext;
 use crate::metrics::WAL_INGEST;
-use crate::pgdatadir_mapping::{DatadirModification, Version};
+use crate::pgdatadir_mapping::*;
 use crate::tenant::PageReconstructError;
 use crate::tenant::Timeline;
 use crate::walrecord::*;
 use crate::ZERO_PAGE;
-use pageserver_api::key::rel_block_to_key;
 use pageserver_api::reltag::{BlockNumber, RelTag, SlruKind};
 use postgres_ffi::pg_constants;
 use postgres_ffi::relfile_utils::{FSM_FORKNUM, INIT_FORKNUM, MAIN_FORKNUM, VISIBILITYMAP_FORKNUM};
@@ -103,9 +102,7 @@ impl WalIngest {
        buf.advance(decoded.main_data_offset);

        assert!(!self.checkpoint_modified);
-        if decoded.xl_xid != pg_constants::INVALID_TRANSACTION_ID
-            && self.checkpoint.update_next_xid(decoded.xl_xid)
-        {
+        if self.checkpoint.update_next_xid(decoded.xl_xid) {
            self.checkpoint_modified = true;
        }

@@ -333,13 +330,8 @@ impl WalIngest {
                        < 0
                    {
                        self.checkpoint.oldestXid = xlog_checkpoint.oldestXid;
+                        self.checkpoint_modified = true;
                    }
-
-                    // Write a new checkpoint key-value pair on every checkpoint record, even
-                    // if nothing really changed. Not strictly required, but it seems nice to
-                    // have some trace of the checkpoint records in the layer files at the same
-                    // LSNs.
-                    self.checkpoint_modified = true;
                }
            }
            pg_constants::RM_LOGICALMSG_ID => {
--- a/pageserver/src/walredo.rs
+++ b/pageserver/src/walredo.rs
@@ -47,10 +47,11 @@ use crate::metrics::{
    WAL_REDO_PROCESS_LAUNCH_DURATION_HISTOGRAM, WAL_REDO_RECORDS_HISTOGRAM,
    WAL_REDO_RECORD_COUNTER, WAL_REDO_TIME,
 };
+use crate::pgdatadir_mapping::key_to_slru_block;
 use crate::repository::Key;
 use crate::walrecord::NeonWalRecord;

-use pageserver_api::key::{key_to_rel_block, key_to_slru_block};
+use pageserver_api::key::key_to_rel_block;
 use pageserver_api::reltag::{RelTag, SlruKind};
 use postgres_ffi::pg_constants;
 use postgres_ffi::relfile_utils::VISIBILITYMAP_FORKNUM;
@@ -836,8 +837,9 @@ impl WalRedoProcess {
        let mut proc = { input }; // TODO: remove this legacy rename, but this keep the patch small.
        let mut nwrite = 0usize;

+        let mut stdin_pollfds = [PollFd::new(proc.stdin.as_raw_fd(), PollFlags::POLLOUT)];
+
        while nwrite < writebuf.len() {
-            let mut stdin_pollfds = [PollFd::new(&proc.stdin, PollFlags::POLLOUT)];
            let n = loop {
                match nix::poll::poll(&mut stdin_pollfds[..], wal_redo_timeout.as_millis() as i32) {
                    Err(nix::errno::Errno::EINTR) => continue,
@@ -876,6 +878,7 @@ impl WalRedoProcess {
        // advancing processed responses number.

        let mut output = self.stdout.lock().unwrap();
+        let mut stdout_pollfds = [PollFd::new(output.stdout.as_raw_fd(), PollFlags::POLLIN)];
        let n_processed_responses = output.n_processed_responses;
        while n_processed_responses + output.pending_responses.len() <= request_no {
            // We expect the WAL redo process to respond with an 8k page image. We read it
@@ -883,7 +886,6 @@ impl WalRedoProcess {
            let mut resultbuf = vec![0; BLCKSZ.into()];
            let mut nresult: usize = 0; // # of bytes read into 'resultbuf' so far
            while nresult < BLCKSZ.into() {
-                let mut stdout_pollfds = [PollFd::new(&output.stdout, PollFlags::POLLIN)];
                // We do two things simultaneously: reading response from stdout
                // and forward any logging information that the child writes to its stderr to the page server's log.
                let n = loop {
--- a/pgxn/neon/control_plane_connector.c
+++ b/pgxn/neon/control_plane_connector.c
@@ -637,7 +637,7 @@ HandleAlterRole(AlterRoleStmt *stmt)
 	ListCell   *option;
 	const char *role_name = stmt->role->rolename;

-	if (RoleIsNeonSuperuser(role_name) && !superuser())
+	if (RoleIsNeonSuperuser(role_name))
 		elog(ERROR, "can't ALTER neon_superuser");

 	foreach(option, stmt->options)
--- a/pgxn/neon/libpagestore.c
+++ b/pgxn/neon/libpagestore.c
@@ -64,26 +64,10 @@ static int max_reconnect_attempts = 60;

 #define MAX_PAGESERVER_CONNSTRING_SIZE 256

-/*
- * The "neon.pageserver_connstring" GUC is marked with the PGC_SIGHUP option,
- * allowing it to be changed using pg_reload_conf(). The control plane can
- * update the connection string if the pageserver crashes, is relocated, or
- * new shards are added. A copy of the current value of the GUC is kept in
- * shared memory, updated by the postmaster, because regular backends don't
- * reload the config during query execution, but we might need to re-establish
- * the pageserver connection with the new connection string even in the middle
- * of a query.
- *
- * The shared memory copy is protected by a lockless algorithm using two
- * atomic counters. The counters allow a backend to quickly check if the value
- * has changed since last access, and to detect and retry copying the value if
- * the postmaster changes the value concurrently. (Postmaster doesn't have a
- * PGPROC entry and therefore cannot use LWLocks.)
- */
 typedef struct
 {
-	pg_atomic_uint64 begin_update_counter;
-	pg_atomic_uint64 end_update_counter;
+	LWLockId	lock;
+	pg_atomic_uint64 update_counter;
 	char		pageserver_connstring[MAX_PAGESERVER_CONNSTRING_SIZE];
 } PagestoreShmemState;

@@ -100,7 +84,7 @@ static bool pageserver_flush(void);
 static void pageserver_disconnect(void);

 static bool
-PagestoreShmemIsValid(void)
+PagestoreShmemIsValid()
 {
 	return pagestore_shared && UsedShmemSegAddr;
 }
@@ -114,58 +98,31 @@ CheckPageserverConnstring(char **newval, void **extra, GucSource source)
 static void
 AssignPageserverConnstring(const char *newval, void *extra)
 {
-	/*
-	 * Only postmaster updates the copy in shared memory.
-	 */
-	if (!PagestoreShmemIsValid() || IsUnderPostmaster)
+	if (!PagestoreShmemIsValid())
 		return;
-
-	pg_atomic_add_fetch_u64(&pagestore_shared->begin_update_counter, 1);
-	pg_write_barrier();
+	LWLockAcquire(pagestore_shared->lock, LW_EXCLUSIVE);
 	strlcpy(pagestore_shared->pageserver_connstring, newval, MAX_PAGESERVER_CONNSTRING_SIZE);
-	pg_write_barrier();
-	pg_atomic_add_fetch_u64(&pagestore_shared->end_update_counter, 1);
+	pg_atomic_fetch_add_u64(&pagestore_shared->update_counter, 1);
+	LWLockRelease(pagestore_shared->lock);
 }

 static bool
-CheckConnstringUpdated(void)
+CheckConnstringUpdated()
 {
 	if (!PagestoreShmemIsValid())
 		return false;
-	return pagestore_local_counter < pg_atomic_read_u64(&pagestore_shared->begin_update_counter);
+	return pagestore_local_counter < pg_atomic_read_u64(&pagestore_shared->update_counter);
 }

 static void
-ReloadConnstring(void)
+ReloadConnstring()
 {
-	uint64		begin_update_counter;
-	uint64		end_update_counter;
-
 	if (!PagestoreShmemIsValid())
 		return;
-
-	/*
-	 * Copy the current settnig from shared to local memory. Postmaster can
-	 * update the value concurrently, in which case we would copy a garbled
-	 * mix of the old and new values. We will detect it because the counter's
-	 * won't match, and retry. But it's important that we don't do anything
-	 * within the retry-loop that would depend on the string having valid
-	 * contents.
-	 */
-	do
-	{
-		begin_update_counter = pg_atomic_read_u64(&pagestore_shared->begin_update_counter);
-		end_update_counter = pg_atomic_read_u64(&pagestore_shared->end_update_counter);
-		pg_read_barrier();
-
-		strlcpy(local_pageserver_connstring, pagestore_shared->pageserver_connstring, sizeof(local_pageserver_connstring));
-		pg_read_barrier();
-	}
-	while (begin_update_counter != end_update_counter
-		   || begin_update_counter != pg_atomic_read_u64(&pagestore_shared->begin_update_counter)
-		   || end_update_counter != pg_atomic_read_u64(&pagestore_shared->end_update_counter));
-
-	pagestore_local_counter = end_update_counter;
+	LWLockAcquire(pagestore_shared->lock, LW_SHARED);
+	strlcpy(local_pageserver_connstring, pagestore_shared->pageserver_connstring, sizeof(local_pageserver_connstring));
+	pagestore_local_counter = pg_atomic_read_u64(&pagestore_shared->update_counter);
+	LWLockRelease(pagestore_shared->lock);
 }

 static bool
@@ -180,7 +137,7 @@ pageserver_connect(int elevel)
 	static TimestampTz last_connect_time = 0;
 	static uint64_t delay_us = MIN_RECONNECT_INTERVAL_USEC;
 	TimestampTz now;
-	uint64_t	us_since_last_connect;
+        uint64_t us_since_last_connect;

 	Assert(!connected);

@@ -190,7 +147,7 @@ pageserver_connect(int elevel)
 	}

 	now = GetCurrentTimestamp();
-	us_since_last_connect = now - last_connect_time;
+        us_since_last_connect = now - last_connect_time;
 	if (us_since_last_connect < delay_us)
 	{
 		pg_usleep(delay_us - us_since_last_connect);
@@ -548,8 +505,8 @@ PagestoreShmemInit(void)
 									   &found);
 	if (!found)
 	{
-		pg_atomic_init_u64(&pagestore_shared->begin_update_counter, 0);
-		pg_atomic_init_u64(&pagestore_shared->end_update_counter, 0);
+		pagestore_shared->lock = &(GetNamedLWLockTranche("neon_libpagestore")->lock);
+		pg_atomic_init_u64(&pagestore_shared->update_counter, 0);
 		AssignPageserverConnstring(page_server_connstring, NULL);
 	}
 	LWLockRelease(AddinShmemInitLock);
@@ -574,6 +531,7 @@ pagestore_shmem_request(void)
 #endif

 	RequestAddinShmemSpace(PagestoreShmemSize());
+	RequestNamedLWLockTranche("neon_libpagestore", 1);
 }

 static void
--- a/proxy/Cargo.toml
+++ b/proxy/Cargo.toml
@@ -5,7 +5,7 @@ edition.workspace = true
 license.workspace = true

 [features]
-default = []
+default = ["testing"]
 testing = []

 [dependencies]
--- a/proxy/src/auth.rs
+++ b/proxy/src/auth.rs
@@ -13,7 +13,7 @@ use password_hack::PasswordHackPayload;
 mod flow;
 pub use flow::*;

-use crate::error::{ReportableError, UserFacingError};
+use crate::{console, error::UserFacingError};
 use std::io;
 use thiserror::Error;

@@ -23,6 +23,15 @@ pub type Result<T> = std::result::Result<T, AuthError>;
 /// Common authentication error.
 #[derive(Debug, Error)]
 pub enum AuthErrorImpl {
+    #[error(transparent)]
+    Link(#[from] backend::LinkAuthError),
+
+    #[error(transparent)]
+    GetAuthInfo(#[from] console::errors::GetAuthInfoError),
+
+    #[error(transparent)]
+    WakeCompute(#[from] console::errors::WakeComputeError),
+
    /// SASL protocol errors (includes [SCRAM](crate::scram)).
    #[error(transparent)]
    Sasl(#[from] crate::sasl::Error),
@@ -90,25 +99,13 @@ impl<E: Into<AuthErrorImpl>> From<E> for AuthError {
    }
 }

-impl ReportableError for AuthError {
-    fn get_error_type(&self) -> crate::error::ErrorKind {
-        match self.0.as_ref() {
-            AuthErrorImpl::Sasl(s) => s.get_error_type(),
-            AuthErrorImpl::BadAuthMethod(_) => crate::error::ErrorKind::User,
-            AuthErrorImpl::MalformedPassword(_) => crate::error::ErrorKind::User,
-            AuthErrorImpl::MissingEndpointName => crate::error::ErrorKind::User,
-            AuthErrorImpl::AuthFailed(_) => crate::error::ErrorKind::User,
-            AuthErrorImpl::Io(_) => crate::error::ErrorKind::Disconnect,
-            AuthErrorImpl::IpAddressNotAllowed => crate::error::ErrorKind::User,
-            AuthErrorImpl::TooManyConnections => crate::error::ErrorKind::RateLimit,
-        }
-    }
-}
-
 impl UserFacingError for AuthError {
    fn to_string_client(&self) -> String {
        use AuthErrorImpl::*;
        match self.0.as_ref() {
+            Link(e) => e.to_string_client(),
+            GetAuthInfo(e) => e.to_string_client(),
+            WakeCompute(e) => e.to_string_client(),
            Sasl(e) => e.to_string_client(),
            AuthFailed(_) => self.to_string(),
            BadAuthMethod(_) => self.to_string(),
--- a/proxy/src/auth/backend.rs
+++ b/proxy/src/auth/backend.rs
@@ -2,27 +2,21 @@ mod classic;
 mod hacks;
 mod link;

-use pq_proto::StartupMessageParams;
+pub use link::LinkAuthError;
 use smol_str::SmolStr;
 use tokio_postgres::config::AuthKeys;

-use crate::auth::backend::link::NeedsLinkAuthentication;
 use crate::auth::credentials::check_peer_addr_is_in_list;
 use crate::auth::validate_password_and_exchange;
 use crate::cache::Cached;
-use crate::cancellation::Session;
-use crate::config::ProxyConfig;
 use crate::console::errors::GetAuthInfoError;
-use crate::console::provider::ConsoleBackend;
 use crate::console::AuthSecret;
 use crate::context::RequestMonitoring;
-use crate::proxy::wake_compute::NeedsWakeCompute;
-use crate::proxy::ClientMode;
+use crate::proxy::connect_compute::handle_try_wake;
+use crate::proxy::retry::retry_after;
 use crate::proxy::NeonOptions;
-use crate::rate_limiter::EndpointRateLimiter;
 use crate::scram;
-use crate::state_machine::{user_facing_error, DynStage, ResultExt, Stage, StageError};
-use crate::stream::{PqStream, Stream};
+use crate::stream::Stream;
 use crate::{
    auth::{self, ComputeUserInfoMaybeEndpoint},
    config::AuthenticationConfig,
@@ -35,11 +29,10 @@ use crate::{
 };
 use futures::TryFutureExt;
 use std::borrow::Cow;
+use std::ops::ControlFlow;
 use std::sync::Arc;
 use tokio::io::{AsyncRead, AsyncWrite};
-use tracing::info;
-
-use self::hacks::NeedsPasswordHack;
+use tracing::{error, info, warn};

 /// This type serves two purposes:
 ///
@@ -50,8 +43,11 @@ use self::hacks::NeedsPasswordHack;
 ///   this helps us provide the credentials only to those auth
 ///   backends which require them for the authentication process.
 pub enum BackendType<'a, T> {
-    /// Cloud API (V2).
-    Console(Cow<'a, ConsoleBackend>, T),
+    /// Current Cloud API (V2).
+    Console(Cow<'a, console::provider::neon::Api>, T),
+    /// Local mock of Cloud API (V2).
+    #[cfg(feature = "testing")]
+    Postgres(Cow<'a, console::provider::mock::Api>, T),
    /// Authentication via a web browser.
    Link(Cow<'a, url::ApiUrl>),
    #[cfg(test)]
@@ -68,15 +64,9 @@ impl std::fmt::Display for BackendType<'_, ()> {
    fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        use BackendType::*;
        match self {
-            Console(api, _) => match &**api {
-                ConsoleBackend::Console(endpoint) => {
-                    fmt.debug_tuple("Console").field(&endpoint.url()).finish()
-                }
-                #[cfg(feature = "testing")]
-                ConsoleBackend::Postgres(endpoint) => {
-                    fmt.debug_tuple("Postgres").field(&endpoint.url()).finish()
-                }
-            },
+            Console(endpoint, _) => fmt.debug_tuple("Console").field(&endpoint.url()).finish(),
+            #[cfg(feature = "testing")]
+            Postgres(endpoint, _) => fmt.debug_tuple("Postgres").field(&endpoint.url()).finish(),
            Link(url) => fmt.debug_tuple("Link").field(&url.as_str()).finish(),
            #[cfg(test)]
            Test(_) => fmt.debug_tuple("Test").finish(),
@@ -91,6 +81,8 @@ impl<T> BackendType<'_, T> {
        use BackendType::*;
        match self {
            Console(c, x) => Console(Cow::Borrowed(c), x),
+            #[cfg(feature = "testing")]
+            Postgres(c, x) => Postgres(Cow::Borrowed(c), x),
            Link(c) => Link(Cow::Borrowed(c)),
            #[cfg(test)]
            Test(x) => Test(*x),
@@ -106,6 +98,8 @@ impl<'a, T> BackendType<'a, T> {
        use BackendType::*;
        match self {
            Console(c, x) => Console(c, f(x)),
+            #[cfg(feature = "testing")]
+            Postgres(c, x) => Postgres(c, f(x)),
            Link(c) => Link(c),
            #[cfg(test)]
            Test(x) => Test(x),
@@ -120,6 +114,8 @@ impl<'a, T, E> BackendType<'a, Result<T, E>> {
        use BackendType::*;
        match self {
            Console(c, x) => x.map(|x| Console(c, x)),
+            #[cfg(feature = "testing")]
+            Postgres(c, x) => x.map(|x| Postgres(c, x)),
            Link(c) => Ok(Link(c)),
            #[cfg(test)]
            Test(x) => Ok(Test(x)),
@@ -176,94 +172,69 @@ impl TryFrom<ComputeUserInfoMaybeEndpoint> for ComputeUserInfo {
    }
 }

-struct NeedsAuthSecret<S> {
-    stream: PqStream<Stream<S>>,
-    api: Cow<'static, ConsoleBackend>,
-    params: StartupMessageParams,
-    allow_self_signed_compute: bool,
+/// True to its name, this function encapsulates our current auth trade-offs.
+/// Here, we choose the appropriate auth flow based on circumstances.
+///
+/// All authentication flows will emit an AuthenticationOk message if successful.
+async fn auth_quirks(
+    ctx: &mut RequestMonitoring,
+    api: &impl console::Api,
+    user_info: ComputeUserInfoMaybeEndpoint,
+    client: &mut stream::PqStream<Stream<impl AsyncRead + AsyncWrite + Unpin>>,
    allow_cleartext: bool,
-    info: ComputeUserInfo,
-    unauthenticated_password: Option<Vec<u8>>,
    config: &'static AuthenticationConfig,
-
-    // monitoring
-    ctx: RequestMonitoring,
-    cancel_session: Session,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsAuthSecret<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("get_auth_secret")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            stream,
-            api,
-            params,
-            allow_cleartext,
-            allow_self_signed_compute,
-            info,
-            unauthenticated_password,
-            config,
-            mut ctx,
-            cancel_session,
-        } = self;
-
-        info!("fetching user's authentication info");
-        let (allowed_ips, stream) = api
-            .get_allowed_ips(&mut ctx, &info)
-            .await
-            .send_error_to_user(&mut ctx, stream)?;
-
-        // check allowed list
-        if !check_peer_addr_is_in_list(&ctx.peer_addr, &allowed_ips) {
-            return Err(user_facing_error(
-                auth::AuthError::ip_address_not_allowed(),
-                &mut ctx,
-                stream,
-            ));
+) -> auth::Result<ComputeCredentials<ComputeCredentialKeys>> {
+    // If there's no project so far, that entails that client doesn't
+    // support SNI or other means of passing the endpoint (project) name.
+    // We now expect to see a very specific payload in the place of password.
+    let (info, unauthenticated_password) = match user_info.try_into() {
+        Err(info) => {
+            let res = hacks::password_hack_no_authentication(info, client, &mut ctx.latency_timer)
+                .await?;
+            ctx.set_endpoint_id(Some(res.info.endpoint.clone()));
+            (res.info, Some(res.keys))
        }
-        let (cached_secret, mut stream) = api
-            .get_role_secret(&mut ctx, &info)
-            .await
-            .send_error_to_user(&mut ctx, stream)?;
+        Ok(info) => (info, None),
+    };

-        let secret = cached_secret.value.clone().unwrap_or_else(|| {
-            // If we don't have an authentication secret, we mock one to
-            // prevent malicious probing (possible due to missing protocol steps).
-            // This mocked secret will never lead to successful authentication.
-            info!("authentication info not found, mocking it");
-            AuthSecret::Scram(scram::ServerSecret::mock(&info.user, rand::random()))
-        });
+    info!("fetching user's authentication info");
+    let allowed_ips = api.get_allowed_ips(ctx, &info).await?;

-        let (keys, stream) = authenticate_with_secret(
-            &mut ctx,
-            secret,
-            info,
-            &mut stream,
-            unauthenticated_password,
-            allow_cleartext,
-            config,
-        )
-        .await
-        .map_err(|e| {
+    // check allowed list
+    if !check_peer_addr_is_in_list(&ctx.peer_addr, &allowed_ips) {
+        return Err(auth::AuthError::ip_address_not_allowed());
+    }
+    let maybe_secret = api.get_role_secret(ctx, &info).await?;
+
+    let cached_secret = maybe_secret.unwrap_or_else(|| {
+        // If we don't have an authentication secret, we mock one to
+        // prevent malicious probing (possible due to missing protocol steps).
+        // This mocked secret will never lead to successful authentication.
+        info!("authentication info not found, mocking it");
+        Cached::new_uncached(AuthSecret::Scram(scram::ServerSecret::mock(
+            &info.user,
+            rand::random(),
+        )))
+    });
+    match authenticate_with_secret(
+        ctx,
+        cached_secret.value.clone(),
+        info,
+        client,
+        unauthenticated_password,
+        allow_cleartext,
+        config,
+    )
+    .await
+    {
+        Ok(keys) => Ok(keys),
+        Err(e) => {
            if e.is_auth_failed() {
                // The password could have been changed, so we invalidate the cache.
                cached_secret.invalidate();
            }
-            e
-        })
-        .send_error_to_user(&mut ctx, stream)?;
-
-        Ok(Box::new(NeedsWakeCompute {
-            stream,
-            api,
-            params,
-            allow_self_signed_compute,
-            creds: keys,
-            ctx,
-            cancel_session,
-        }))
+            Err(e)
+        }
    }
 }

@@ -304,6 +275,49 @@ async fn authenticate_with_secret(
    classic::authenticate(info, client, config, &mut ctx.latency_timer, secret).await
 }

+/// Authenticate the user and then wake a compute (or retrieve an existing compute session from cache)
+/// only if authentication was successfuly.
+async fn auth_and_wake_compute(
+    ctx: &mut RequestMonitoring,
+    api: &impl console::Api,
+    user_info: ComputeUserInfoMaybeEndpoint,
+    client: &mut stream::PqStream<Stream<impl AsyncRead + AsyncWrite + Unpin>>,
+    allow_cleartext: bool,
+    config: &'static AuthenticationConfig,
+) -> auth::Result<(CachedNodeInfo, ComputeUserInfo)> {
+    let compute_credentials =
+        auth_quirks(ctx, api, user_info, client, allow_cleartext, config).await?;
+
+    let mut num_retries = 0;
+    let mut node = loop {
+        let wake_res = api.wake_compute(ctx, &compute_credentials.info).await;
+        match handle_try_wake(wake_res, num_retries) {
+            Err(e) => {
+                error!(error = ?e, num_retries, retriable = false, "couldn't wake compute node");
+                return Err(e.into());
+            }
+            Ok(ControlFlow::Continue(e)) => {
+                warn!(error = ?e, num_retries, retriable = true, "couldn't wake compute node");
+            }
+            Ok(ControlFlow::Break(n)) => break n,
+        }
+
+        let wait_duration = retry_after(num_retries);
+        num_retries += 1;
+        tokio::time::sleep(wait_duration).await;
+    };
+
+    ctx.set_project(node.aux.clone());
+
+    match compute_credentials.keys {
+        #[cfg(feature = "testing")]
+        ComputeCredentialKeys::Password(password) => node.config.password(password),
+        ComputeCredentialKeys::AuthKeys(auth_keys) => node.config.auth_keys(auth_keys),
+    };
+
+    Ok((node, compute_credentials.info))
+}
+
 impl<'a> BackendType<'a, ComputeUserInfoMaybeEndpoint> {
    /// Get compute endpoint name from the credentials.
    pub fn get_endpoint(&self) -> Option<SmolStr> {
@@ -311,6 +325,8 @@ impl<'a> BackendType<'a, ComputeUserInfoMaybeEndpoint> {

        match self {
            Console(_, user_info) => user_info.project.clone(),
+            #[cfg(feature = "testing")]
+            Postgres(_, user_info) => user_info.project.clone(),
            Link(_) => Some("link".into()),
            #[cfg(test)]
            Test(_) => Some("test".into()),
@@ -323,101 +339,70 @@ impl<'a> BackendType<'a, ComputeUserInfoMaybeEndpoint> {

        match self {
            Console(_, user_info) => &user_info.user,
+            #[cfg(feature = "testing")]
+            Postgres(_, user_info) => &user_info.user,
            Link(_) => "link",
            #[cfg(test)]
            Test(_) => "test",
        }
    }
-}

-pub struct NeedsAuthentication<S> {
-    pub stream: PqStream<Stream<S>>,
-    pub creds: BackendType<'static, auth::ComputeUserInfoMaybeEndpoint>,
-    pub params: StartupMessageParams,
-    pub endpoint_rate_limiter: Arc<EndpointRateLimiter>,
-    pub mode: ClientMode,
-    pub config: &'static ProxyConfig,
+    /// Authenticate the client via the requested backend, possibly using credentials.
+    #[tracing::instrument(fields(allow_cleartext = allow_cleartext), skip_all)]
+    pub async fn authenticate(
+        self,
+        ctx: &mut RequestMonitoring,
+        client: &mut stream::PqStream<Stream<impl AsyncRead + AsyncWrite + Unpin>>,
+        allow_cleartext: bool,
+        config: &'static AuthenticationConfig,
+    ) -> auth::Result<(CachedNodeInfo, BackendType<'a, ComputeUserInfo>)> {
+        use BackendType::*;

-    // monitoring
-    pub ctx: RequestMonitoring,
-    pub cancel_session: Session,
-}
+        let res = match self {
+            Console(api, user_info) => {
+                info!(
+                    user = &*user_info.user,
+                    project = user_info.project(),
+                    "performing authentication using the console"
+                );

-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsAuthentication<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("authenticate")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            stream,
-            creds,
-            params,
-            endpoint_rate_limiter,
-            mode,
-            config,
-            mut ctx,
-            cancel_session,
-        } = self;
-
-        // check rate limit
-        if let Some(ep) = creds.get_endpoint() {
-            if !endpoint_rate_limiter.check(ep) {
-                return Err(user_facing_error(
-                    auth::AuthError::too_many_connections(),
-                    &mut ctx,
-                    stream,
-                ));
+                let (cache_info, user_info) =
+                    auth_and_wake_compute(ctx, &*api, user_info, client, allow_cleartext, config)
+                        .await?;
+                (cache_info, BackendType::Console(api, user_info))
            }
-        }
+            #[cfg(feature = "testing")]
+            Postgres(api, user_info) => {
+                info!(
+                    user = &*user_info.user,
+                    project = user_info.project(),
+                    "performing authentication using a local postgres instance"
+                );

-        let allow_self_signed_compute = mode.allow_self_signed_compute(config);
-        let allow_cleartext = mode.allow_cleartext();
-
-        match creds {
-            BackendType::Console(api, creds) => {
-                // If there's no project so far, that entails that client doesn't
-                // support SNI or other means of passing the endpoint (project) name.
-                // We now expect to see a very specific payload in the place of password.
-                match creds.try_into() {
-                    Err(info) => Ok(Box::new(NeedsPasswordHack {
-                        stream,
-                        api,
-                        params,
-                        allow_self_signed_compute,
-                        info,
-                        allow_cleartext,
-                        config: &config.authentication_config,
-                        ctx,
-                        cancel_session,
-                    })),
-                    Ok(info) => Ok(Box::new(NeedsAuthSecret {
-                        stream,
-                        api,
-                        params,
-                        allow_self_signed_compute,
-                        info,
-                        unauthenticated_password: None,
-                        allow_cleartext,
-                        config: &config.authentication_config,
-                        ctx,
-                        cancel_session,
-                    })),
-                }
+                let (cache_info, user_info) =
+                    auth_and_wake_compute(ctx, &*api, user_info, client, allow_cleartext, config)
+                        .await?;
+                (cache_info, BackendType::Postgres(api, user_info))
            }
            // NOTE: this auth backend doesn't use client credentials.
-            BackendType::Link(link) => Ok(Box::new(NeedsLinkAuthentication {
-                stream,
-                link,
-                params,
-                allow_self_signed_compute,
-                ctx,
-                cancel_session,
-            })),
+            Link(url) => {
+                info!("performing link authentication");
+
+                let node_info = link::authenticate(&url, client).await?;
+
+                (
+                    CachedNodeInfo::new_uncached(node_info),
+                    BackendType::Link(url),
+                )
+            }
            #[cfg(test)]
-            BackendType::Test(_) => {
+            Test(_) => {
                unreachable!("this function should never be called in the test backend")
            }
-        }
+        };
+
+        info!("user successfully authenticated");
+        Ok(res)
    }
 }

@@ -429,6 +414,8 @@ impl BackendType<'_, ComputeUserInfo> {
        use BackendType::*;
        match self {
            Console(api, user_info) => api.get_allowed_ips(ctx, user_info).await,
+            #[cfg(feature = "testing")]
+            Postgres(api, user_info) => api.get_allowed_ips(ctx, user_info).await,
            Link(_) => Ok(Cached::new_uncached(Arc::new(vec![]))),
            #[cfg(test)]
            Test(x) => Ok(Cached::new_uncached(Arc::new(x.get_allowed_ips()?))),
@@ -445,6 +432,8 @@ impl BackendType<'_, ComputeUserInfo> {

        match self {
            Console(api, user_info) => api.wake_compute(ctx, user_info).map_ok(Some).await,
+            #[cfg(feature = "testing")]
+            Postgres(api, user_info) => api.wake_compute(ctx, user_info).map_ok(Some).await,
            Link(_) => Ok(None),
            #[cfg(test)]
            Test(x) => x.wake_compute().map(Some),
--- a/proxy/src/auth/backend/hacks.rs
+++ b/proxy/src/auth/backend/hacks.rs
@@ -1,21 +1,13 @@
-use std::borrow::Cow;
-
 use super::{
    ComputeCredentialKeys, ComputeCredentials, ComputeUserInfo, ComputeUserInfoNoEndpoint,
-    NeedsAuthSecret,
 };
 use crate::{
    auth::{self, AuthFlow},
-    cancellation::Session,
-    config::AuthenticationConfig,
-    console::{provider::ConsoleBackend, AuthSecret},
-    context::RequestMonitoring,
+    console::AuthSecret,
    metrics::LatencyTimer,
    sasl,
-    state_machine::{DynStage, ResultExt, Stage, StageError},
-    stream::{self, PqStream, Stream},
+    stream::{self, Stream},
 };
-use pq_proto::StartupMessageParams;
 use tokio::io::{AsyncRead, AsyncWrite};
 use tracing::{info, warn};

@@ -54,7 +46,7 @@ pub async fn authenticate_cleartext(
 /// Workaround for clients which don't provide an endpoint (project) name.
 /// Similar to [`authenticate_cleartext`], but there's a specific password format,
 /// and passwords are not yet validated (we don't know how to validate them!)
-async fn password_hack_no_authentication(
+pub async fn password_hack_no_authentication(
    info: ComputeUserInfoNoEndpoint,
    client: &mut stream::PqStream<Stream<impl AsyncRead + AsyncWrite + Unpin>>,
    latency_timer: &mut LatencyTimer,
@@ -82,47 +74,3 @@ async fn password_hack_no_authentication(
        keys: payload.password,
    })
 }
-
-pub struct NeedsPasswordHack<S> {
-    pub stream: PqStream<Stream<S>>,
-    pub api: Cow<'static, ConsoleBackend>,
-    pub params: StartupMessageParams,
-    pub allow_self_signed_compute: bool,
-    pub allow_cleartext: bool,
-    pub info: ComputeUserInfoNoEndpoint,
-    pub config: &'static AuthenticationConfig,
-
-    // monitoring
-    pub ctx: RequestMonitoring,
-    pub cancel_session: Session,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsPasswordHack<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("password_hack")
-    }
-    async fn run(mut self) -> Result<DynStage, StageError> {
-        let (res, stream) = password_hack_no_authentication(
-            self.info,
-            &mut self.stream,
-            &mut self.ctx.latency_timer,
-        )
-        .await
-        .send_error_to_user(&mut self.ctx, self.stream)?;
-
-        self.ctx.set_endpoint_id(Some(res.info.endpoint.clone()));
-        Ok(Box::new(NeedsAuthSecret {
-            stream,
-            info: res.info,
-            unauthenticated_password: Some(res.keys),
-
-            api: self.api,
-            params: self.params,
-            allow_self_signed_compute: self.allow_self_signed_compute,
-            allow_cleartext: self.allow_cleartext,
-            ctx: self.ctx,
-            cancel_session: self.cancel_session,
-            config: self.config,
-        }))
-    }
-}
--- a/proxy/src/auth/backend/link.rs
+++ b/proxy/src/auth/backend/link.rs
@@ -1,20 +1,41 @@
-use std::borrow::Cow;
-
 use crate::{
-    auth::BackendType,
-    cancellation::Session,
-    compute,
-    console::{self, mgmt::ComputeReady, provider::NodeInfo, CachedNodeInfo},
-    context::RequestMonitoring,
-    proxy::connect_compute::{NeedsComputeConnection, TcpMechanism},
-    state_machine::{DynStage, ResultExt, Stage, StageError},
-    stream::{PqStream, Stream},
-    waiters::Waiter,
+    auth, compute,
+    console::{self, provider::NodeInfo},
+    error::UserFacingError,
+    stream::PqStream,
+    waiters,
 };
-use pq_proto::{BeMessage as Be, StartupMessageParams};
+use pq_proto::BeMessage as Be;
+use thiserror::Error;
 use tokio::io::{AsyncRead, AsyncWrite};
 use tokio_postgres::config::SslMode;
-use tracing::info;
+use tracing::{info, info_span};
+
+#[derive(Debug, Error)]
+pub enum LinkAuthError {
+    /// Authentication error reported by the console.
+    #[error("Authentication failed: {0}")]
+    AuthFailed(String),
+
+    #[error(transparent)]
+    WaiterRegister(#[from] waiters::RegisterError),
+
+    #[error(transparent)]
+    WaiterWait(#[from] waiters::WaitError),
+
+    #[error(transparent)]
+    Io(#[from] std::io::Error),
+}
+
+impl UserFacingError for LinkAuthError {
+    fn to_string_client(&self) -> String {
+        use LinkAuthError::*;
+        match self {
+            AuthFailed(_) => self.to_string(),
+            _ => "Internal error".to_string(),
+        }
+    }
+}

 fn hello_message(redirect_uri: &reqwest::Url, session_id: &str) -> String {
    format!(
@@ -32,146 +53,57 @@ pub fn new_psql_session_id() -> String {
    hex::encode(rand::random::<[u8; 8]>())
 }

-pub struct NeedsLinkAuthentication<S> {
-    pub stream: PqStream<Stream<S>>,
-    pub link: Cow<'static, crate::url::ApiUrl>,
-    pub params: StartupMessageParams,
-    pub allow_self_signed_compute: bool,
+pub(super) async fn authenticate(
+    link_uri: &reqwest::Url,
+    client: &mut PqStream<impl AsyncRead + AsyncWrite + Unpin>,
+) -> auth::Result<NodeInfo> {
+    let psql_session_id = new_psql_session_id();
+    let span = info_span!("link", psql_session_id = &psql_session_id);
+    let greeting = hello_message(link_uri, &psql_session_id);

-    // monitoring
-    pub ctx: RequestMonitoring,
-    pub cancel_session: Session,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsLinkAuthentication<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("link", psql_session_id = tracing::field::Empty)
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            mut stream,
-            link,
-            params,
-            allow_self_signed_compute,
-            mut ctx,
-            cancel_session,
-        } = self;
-
-        // registering waiter can fail if we get unlucky with rng.
-        // just try again.
-        let (psql_session_id, waiter) = loop {
-            let psql_session_id = new_psql_session_id();
-
-            match console::mgmt::get_waiter(&psql_session_id) {
-                Ok(waiter) => break (psql_session_id, waiter),
-                Err(_e) => continue,
-            }
-        };
-        tracing::Span::current().record("psql_session_id", &psql_session_id);
-        let greeting = hello_message(&link, &psql_session_id);
-
-        info!("sending the auth URL to the user");
-
-        stream
-            .write_message_noflush(&Be::AuthenticationOk)
-            .and_then(|s| s.write_message_noflush(&Be::CLIENT_ENCODING))
-            .and_then(|s| s.write_message_noflush(&Be::NoticeResponse(&greeting)))
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Service)?
-            .flush()
-            .await
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Disconnect)?;
-
-        Ok(Box::new(NeedsLinkAuthenticationResponse {
-            stream,
-            link,
-            params,
-            allow_self_signed_compute,
-            waiter,
-            psql_session_id,
-            ctx,
-            cancel_session,
-        }))
-    }
-}
-
-struct NeedsLinkAuthenticationResponse<S> {
-    stream: PqStream<Stream<S>>,
-    link: Cow<'static, crate::url::ApiUrl>,
-    params: StartupMessageParams,
-    allow_self_signed_compute: bool,
-    waiter: Waiter<'static, ComputeReady>,
-    psql_session_id: String,
-
-    // monitoring
-    ctx: RequestMonitoring,
-    cancel_session: Session,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage
-    for NeedsLinkAuthenticationResponse<S>
-{
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("link_wait", psql_session_id = self.psql_session_id)
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            mut stream,
-            link,
-            params,
-            allow_self_signed_compute,
-            waiter,
-            psql_session_id: _,
-            mut ctx,
-            cancel_session,
-        } = self;
+    let db_info = console::mgmt::with_waiter(psql_session_id, |waiter| async {
+        // Give user a URL to spawn a new database.
+        info!(parent: &span, "sending the auth URL to the user");
+        client
+            .write_message_noflush(&Be::AuthenticationOk)?
+            .write_message_noflush(&Be::CLIENT_ENCODING)?
+            .write_message(&Be::NoticeResponse(&greeting))
+            .await?;

        // Wait for web console response (see `mgmt`).
-        info!("waiting for console's reply...");
-        let db_info = waiter
-            .await
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Service)?;
+        info!(parent: &span, "waiting for console's reply...");
+        waiter.await?.map_err(LinkAuthError::AuthFailed)
+    })
+    .await?;

-        stream
-            .write_message_noflush(&Be::NoticeResponse("Connecting to database."))
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Service)?;
+    client.write_message_noflush(&Be::NoticeResponse("Connecting to database."))?;

-        // This config should be self-contained, because we won't
-        // take username or dbname from client's startup message.
-        let mut config = compute::ConnCfg::new();
-        config
-            .host(&db_info.host)
-            .port(db_info.port)
-            .dbname(&db_info.dbname)
-            .user(&db_info.user);
+    // This config should be self-contained, because we won't
+    // take username or dbname from client's startup message.
+    let mut config = compute::ConnCfg::new();
+    config
+        .host(&db_info.host)
+        .port(db_info.port)
+        .dbname(&db_info.dbname)
+        .user(&db_info.user);

-        // Backwards compatibility. pg_sni_proxy uses "--" in domain names
-        // while direct connections do not. Once we migrate to pg_sni_proxy
-        // everywhere, we can remove this.
-        if db_info.host.contains("--") {
-            // we need TLS connection with SNI info to properly route it
-            config.ssl_mode(SslMode::Require);
-        } else {
-            config.ssl_mode(SslMode::Disable);
-        }
-
-        if let Some(password) = db_info.password {
-            config.password(password.as_ref());
-        }
-
-        let node_info = CachedNodeInfo::new_uncached(NodeInfo {
-            config,
-            aux: db_info.aux,
-            allow_self_signed_compute,
-        });
-        let user_info = BackendType::Link(link);
-
-        Ok(Box::new(NeedsComputeConnection {
-            stream,
-            user_info,
-            mechanism: TcpMechanism { params },
-            node_info,
-            ctx,
-            cancel_session,
-        }))
+    // Backwards compatibility. pg_sni_proxy uses "--" in domain names
+    // while direct connections do not. Once we migrate to pg_sni_proxy
+    // everywhere, we can remove this.
+    if db_info.host.contains("--") {
+        // we need TLS connection with SNI info to properly route it
+        config.ssl_mode(SslMode::Require);
+    } else {
+        config.ssl_mode(SslMode::Disable);
    }
+
+    if let Some(password) = db_info.password {
+        config.password(password.as_ref());
+    }
+
+    Ok(NodeInfo {
+        config,
+        aux: db_info.aux,
+        allow_self_signed_compute: false, // caller may override
+    })
 }
--- a/proxy/src/auth/credentials.rs
+++ b/proxy/src/auth/credentials.rs
@@ -1,11 +1,8 @@
 //! User credentials used in authentication.

 use crate::{
-    auth::password_hack::parse_endpoint_param,
-    context::RequestMonitoring,
-    error::{ReportableError, UserFacingError},
-    metrics::NUM_CONNECTION_ACCEPTED_BY_SNI,
-    proxy::NeonOptions,
+    auth::password_hack::parse_endpoint_param, context::RequestMonitoring, error::UserFacingError,
+    metrics::NUM_CONNECTION_ACCEPTED_BY_SNI, proxy::NeonOptions,
 };
 use itertools::Itertools;
 use pq_proto::StartupMessageParams;
@@ -36,24 +33,7 @@ pub enum ComputeUserInfoParseError {
    MalformedProjectName(SmolStr),
 }

-impl ReportableError for ComputeUserInfoParseError {
-    fn get_error_type(&self) -> crate::error::ErrorKind {
-        match self {
-            ComputeUserInfoParseError::MissingKey(_) => crate::error::ErrorKind::User,
-            ComputeUserInfoParseError::InconsistentProjectNames { .. } => {
-                crate::error::ErrorKind::User
-            }
-            ComputeUserInfoParseError::UnknownCommonName { .. } => crate::error::ErrorKind::User,
-            ComputeUserInfoParseError::MalformedProjectName(_) => crate::error::ErrorKind::User,
-        }
-    }
-}
-
-impl UserFacingError for ComputeUserInfoParseError {
-    fn to_string_client(&self) -> String {
-        self.to_string()
-    }
-}
+impl UserFacingError for ComputeUserInfoParseError {}

 /// Various client credentials which we use for authentication.
 /// Note that we don't store any kind of client key or password here.
--- a/proxy/src/bin/pg_sni_router.rs
+++ b/proxy/src/bin/pg_sni_router.rs
@@ -164,13 +164,6 @@ async fn task_main(
        let tls_config = Arc::clone(&tls_config);
        let dest_suffix = Arc::clone(&dest_suffix);

-        let root_span = tracing::info_span!(
-            "handle_client",
-            ?session_id,
-            endpoint = tracing::field::Empty
-        );
-        let root_span2 = root_span.clone();
-
        connections.spawn(
            async move {
                socket
@@ -178,13 +171,8 @@ async fn task_main(
                    .context("failed to set socket option")?;

                info!(%peer_addr, "serving");
-                let mut ctx = RequestMonitoring::new(
-                    session_id,
-                    peer_addr.ip(),
-                    "sni_router",
-                    "sni",
-                    root_span2,
-                );
+                let mut ctx =
+                    RequestMonitoring::new(session_id, peer_addr.ip(), "sni_router", "sni");
                handle_client(
                    &mut ctx,
                    dest_suffix,
@@ -198,7 +186,7 @@ async fn task_main(
                // Acknowledge that the task has finished with an error.
                error!("per-client task finished with an error: {e:#}");
            })
-            .instrument(root_span),
+            .instrument(tracing::info_span!("handle_client", ?session_id)),
        );
    }

@@ -283,7 +271,6 @@ async fn handle_client(

    let client = tokio::net::TcpStream::connect(destination).await?;

-    ctx.log();
    let metrics_aux: MetricsAuxInfo = Default::default();
-    proxy::proxy::pass::proxy_pass(tls_stream, client, metrics_aux).await
+    proxy::proxy::proxy_pass(ctx, tls_stream, client, metrics_aux).await
 }
--- a/proxy/src/bin/proxy.rs
+++ b/proxy/src/bin/proxy.rs
@@ -249,19 +249,12 @@ async fn main() -> anyhow::Result<()> {
    }

    if let auth::BackendType::Console(api, _) = &config.auth_backend {
-        match &**api {
-            proxy::console::provider::ConsoleBackend::Console(api) => {
-                let cache = api.caches.project_info.clone();
-                if let Some(url) = args.redis_notifications {
-                    info!("Starting redis notifications listener ({url})");
-                    maintenance_tasks
-                        .spawn(notifications::task_main(url.to_owned(), cache.clone()));
-                }
-                maintenance_tasks.spawn(async move { cache.clone().gc_worker().await });
-            }
-            #[cfg(feature = "testing")]
-            proxy::console::provider::ConsoleBackend::Postgres(_) => {}
+        let cache = api.caches.project_info.clone();
+        if let Some(url) = args.redis_notifications {
+            info!("Starting redis notifications listener ({url})");
+            maintenance_tasks.spawn(notifications::task_main(url.to_owned(), cache.clone()));
        }
+        maintenance_tasks.spawn(async move { cache.clone().gc_worker().await });
    }

    let maintenance = loop {
@@ -358,15 +351,13 @@ fn build_config(args: &ProxyCliArgs) -> anyhow::Result<&'static ProxyConfig> {
            let endpoint = http::Endpoint::new(url, http::new_client(rate_limiter_config));

            let api = console::provider::neon::Api::new(endpoint, caches, locks);
-            let api = console::provider::ConsoleBackend::Console(api);
            auth::BackendType::Console(Cow::Owned(api), ())
        }
        #[cfg(feature = "testing")]
        AuthBackend::Postgres => {
            let url = args.auth_endpoint.parse()?;
            let api = console::provider::mock::Api::new(url);
-            let api = console::provider::ConsoleBackend::Postgres(api);
-            auth::BackendType::Console(Cow::Owned(api), ())
+            auth::BackendType::Postgres(Cow::Owned(api), ())
        }
        AuthBackend::Link => {
            let url = args.uri.parse()?;
--- a/proxy/src/cache/project_info.rs
+++ b/proxy/src/cache/project_info.rs
@@ -44,7 +44,7 @@ impl<T> From<T> for Entry<T> {

 #[derive(Default)]
 struct EndpointInfo {
-    secret: std::collections::HashMap<SmolStr, Entry<Option<AuthSecret>>>,
+    secret: std::collections::HashMap<SmolStr, Entry<AuthSecret>>,
    allowed_ips: Option<Entry<Arc<Vec<SmolStr>>>>,
 }

@@ -60,7 +60,7 @@ impl EndpointInfo {
        role_name: &SmolStr,
        valid_since: Instant,
        ignore_cache_since: Option<Instant>,
-    ) -> Option<(Option<AuthSecret>, bool)> {
+    ) -> Option<(AuthSecret, bool)> {
        if let Some(secret) = self.secret.get(role_name) {
            if valid_since < secret.created_at {
                return Some((
@@ -169,7 +169,7 @@ impl ProjectInfoCacheImpl {
        &self,
        endpoint_id: &SmolStr,
        role_name: &SmolStr,
-    ) -> Option<Cached<&Self, Option<AuthSecret>>> {
+    ) -> Option<Cached<&Self, AuthSecret>> {
        let (valid_since, ignore_cache_since) = self.get_cache_times();
        let endpoint_info = self.cache.get(endpoint_id)?;
        let (value, ignore_cache) =
@@ -208,7 +208,7 @@ impl ProjectInfoCacheImpl {
        project_id: &SmolStr,
        endpoint_id: &SmolStr,
        role_name: &SmolStr,
-        secret: Option<AuthSecret>,
+        secret: AuthSecret,
    ) {
        if self.cache.len() >= self.config.size {
            // If there are too many entries, wait until the next gc cycle.
@@ -266,7 +266,7 @@ impl ProjectInfoCacheImpl {
            tokio::time::interval(self.config.gc_interval / (self.cache.shards().len()) as u32);
        loop {
            interval.tick().await;
-            if self.cache.len() < self.config.size {
+            if self.cache.len() <= self.config.size {
                // If there are not too many entries, wait until the next gc cycle.
                continue;
            }
@@ -364,11 +364,8 @@ mod tests {
        let endpoint_id = "endpoint".into();
        let user1: SmolStr = "user1".into();
        let user2: SmolStr = "user2".into();
-        let secret1 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user1.as_str(),
-            [1; 32],
-        )));
-        let secret2 = None;
+        let secret1 = AuthSecret::Scram(ServerSecret::mock(user1.as_str(), [1; 32]));
+        let secret2 = AuthSecret::Scram(ServerSecret::mock(user2.as_str(), [2; 32]));
        let allowed_ips = Arc::new(vec!["allowed_ip1".into(), "allowed_ip2".into()]);
        cache.insert_role_secret(&project_id, &endpoint_id, &user1, secret1.clone());
        cache.insert_role_secret(&project_id, &endpoint_id, &user2, secret2.clone());
@@ -383,10 +380,7 @@ mod tests {

        // Shouldn't add more than 2 roles.
        let user3: SmolStr = "user3".into();
-        let secret3 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user3.as_str(),
-            [3; 32],
-        )));
+        let secret3 = AuthSecret::Scram(ServerSecret::mock(user3.as_str(), [3; 32]));
        cache.insert_role_secret(&project_id, &endpoint_id, &user3, secret3.clone());
        assert!(cache.get_role_secret(&endpoint_id, &user3).is_none());

@@ -419,14 +413,8 @@ mod tests {
        let endpoint_id = "endpoint".into();
        let user1: SmolStr = "user1".into();
        let user2: SmolStr = "user2".into();
-        let secret1 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user1.as_str(),
-            [1; 32],
-        )));
-        let secret2 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user2.as_str(),
-            [2; 32],
-        )));
+        let secret1 = AuthSecret::Scram(ServerSecret::mock(user1.as_str(), [1; 32]));
+        let secret2 = AuthSecret::Scram(ServerSecret::mock(user2.as_str(), [2; 32]));
        let allowed_ips = Arc::new(vec!["allowed_ip1".into(), "allowed_ip2".into()]);
        cache.insert_role_secret(&project_id, &endpoint_id, &user1, secret1.clone());
        cache.insert_role_secret(&project_id, &endpoint_id, &user2, secret2.clone());
@@ -471,14 +459,8 @@ mod tests {
        let endpoint_id = "endpoint".into();
        let user1: SmolStr = "user1".into();
        let user2: SmolStr = "user2".into();
-        let secret1 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user1.as_str(),
-            [1; 32],
-        )));
-        let secret2 = Some(AuthSecret::Scram(ServerSecret::mock(
-            user2.as_str(),
-            [2; 32],
-        )));
+        let secret1 = AuthSecret::Scram(ServerSecret::mock(user1.as_str(), [1; 32]));
+        let secret2 = AuthSecret::Scram(ServerSecret::mock(user2.as_str(), [2; 32]));
        let allowed_ips = Arc::new(vec!["allowed_ip1".into(), "allowed_ip2".into()]);
        cache.insert_role_secret(&project_id, &endpoint_id, &user1, secret1.clone());
        cache.clone().disable_ttl();
--- a/proxy/src/cancellation.rs
+++ b/proxy/src/cancellation.rs
@@ -1,7 +1,7 @@
-use anyhow::Context;
+use anyhow::{bail, Context};
 use dashmap::DashMap;
 use pq_proto::CancelKeyData;
-use std::{net::SocketAddr, sync::Arc};
+use std::net::SocketAddr;
 use tokio::net::TcpStream;
 use tokio_postgres::{CancelToken, NoTls};
 use tracing::info;
@@ -25,33 +25,39 @@ impl CancelMap {
    }

    /// Run async action within an ephemeral session identified by [`CancelKeyData`].
-    pub fn get_session(self: Arc<Self>) -> Session {
+    pub async fn with_session<'a, F, R, V>(&'a self, f: F) -> anyhow::Result<V>
+    where
+        F: FnOnce(Session<'a>) -> R,
+        R: std::future::Future<Output = anyhow::Result<V>>,
+    {
        // HACK: We'd rather get the real backend_pid but tokio_postgres doesn't
        // expose it and we don't want to do another roundtrip to query
        // for it. The client will be able to notice that this is not the
        // actual backend_pid, but backend_pid is not used for anything
        // so it doesn't matter.
-        let key = loop {
-            let key = rand::random();
+        let key = rand::random();

-            // Random key collisions are unlikely to happen here, but they're still possible,
-            // which is why we have to take care not to rewrite an existing key.
-            match self.0.entry(key) {
-                dashmap::mapref::entry::Entry::Occupied(_) => {
-                    continue;
-                }
-                dashmap::mapref::entry::Entry::Vacant(e) => {
-                    e.insert(None);
-                }
+        // Random key collisions are unlikely to happen here, but they're still possible,
+        // which is why we have to take care not to rewrite an existing key.
+        match self.0.entry(key) {
+            dashmap::mapref::entry::Entry::Occupied(_) => {
+                bail!("query cancellation key already exists: {key}")
            }
-            break key;
-        };
+            dashmap::mapref::entry::Entry::Vacant(e) => {
+                e.insert(None);
+            }
+        }
+
+        // This will guarantee that the session gets dropped
+        // as soon as the future is finished.
+        scopeguard::defer! {
+            self.0.remove(&key);
+            info!("dropped query cancellation key {key}");
+        }

        info!("registered new query cancellation key {key}");
-        Session {
-            key,
-            cancel_map: self,
-        }
+        let session = Session::new(key, self);
+        f(session).await
    }

    #[cfg(test)]
@@ -92,17 +98,23 @@ impl CancelClosure {
 }

 /// Helper for registering query cancellation tokens.
-pub struct Session {
+pub struct Session<'a> {
    /// The user-facing key identifying this session.
    key: CancelKeyData,
    /// The [`CancelMap`] this session belongs to.
-    cancel_map: Arc<CancelMap>,
+    cancel_map: &'a CancelMap,
 }

-impl Session {
+impl<'a> Session<'a> {
+    fn new(key: CancelKeyData, cancel_map: &'a CancelMap) -> Self {
+        Self { key, cancel_map }
+    }
+}
+
+impl Session<'_> {
    /// Store the cancel token for the given session.
    /// This enables query cancellation in `crate::proxy::prepare_client_connection`.
-    pub fn enable_query_cancellation(&self, cancel_closure: CancelClosure) -> CancelKeyData {
+    pub fn enable_query_cancellation(self, cancel_closure: CancelClosure) -> CancelKeyData {
        info!("enabling query cancellation for this session");
        self.cancel_map.0.insert(self.key, Some(cancel_closure));

@@ -110,26 +122,37 @@ impl Session {
    }
 }

-impl Drop for Session {
-    fn drop(&mut self) {
-        self.cancel_map.0.remove(&self.key);
-        info!("dropped query cancellation key {}", &self.key);
-    }
-}
-
 #[cfg(test)]
 mod tests {
    use super::*;
+    use once_cell::sync::Lazy;

    #[tokio::test]
    async fn check_session_drop() -> anyhow::Result<()> {
-        let cancel_map: Arc<CancelMap> = Default::default();
+        static CANCEL_MAP: Lazy<CancelMap> = Lazy::new(Default::default);
+
+        let (tx, rx) = tokio::sync::oneshot::channel();
+        let task = tokio::spawn(CANCEL_MAP.with_session(|session| async move {
+            assert!(CANCEL_MAP.contains(&session));
+
+            tx.send(()).expect("failed to send");
+            futures::future::pending::<()>().await; // sleep forever
+
+            Ok(())
+        }));
+
+        // Wait until the task has been spawned.
+        rx.await.context("failed to hear from the task")?;
+
+        // Drop the session's entry by cancelling the task.
+        task.abort();
+        let error = task.await.expect_err("task should have failed");
+        if !error.is_cancelled() {
+            anyhow::bail!(error);
+        }

-        let session = cancel_map.clone().get_session();
-        assert!(cancel_map.contains(&session));
-        drop(session);
        // Check that the session has been dropped.
-        assert!(cancel_map.is_empty());
+        assert!(CANCEL_MAP.is_empty());

        Ok(())
    }
--- a/proxy/src/compute.rs
+++ b/proxy/src/compute.rs
@@ -1,10 +1,6 @@
 use crate::{
-    auth::parse_endpoint_param,
-    cancellation::CancelClosure,
-    console::errors::WakeComputeError,
-    context::RequestMonitoring,
-    error::{ReportableError, UserFacingError},
-    metrics::NUM_DB_CONNECTIONS_GAUGE,
+    auth::parse_endpoint_param, cancellation::CancelClosure, console::errors::WakeComputeError,
+    context::RequestMonitoring, error::UserFacingError, metrics::NUM_DB_CONNECTIONS_GAUGE,
    proxy::neon_option,
 };
 use futures::{FutureExt, TryFutureExt};
@@ -36,17 +32,6 @@ pub enum ConnectionError {
    WakeComputeError(#[from] WakeComputeError),
 }

-impl ReportableError for ConnectionError {
-    fn get_error_type(&self) -> crate::error::ErrorKind {
-        match self {
-            ConnectionError::Postgres(_) => crate::error::ErrorKind::Compute,
-            ConnectionError::CouldNotConnect(_) => crate::error::ErrorKind::Compute,
-            ConnectionError::TlsError(_) => crate::error::ErrorKind::Compute,
-            ConnectionError::WakeComputeError(_) => crate::error::ErrorKind::ControlPlane,
-        }
-    }
-}
-
 impl UserFacingError for ConnectionError {
    fn to_string_client(&self) -> String {
        use ConnectionError::*;
--- a/proxy/src/console/mgmt.rs
+++ b/proxy/src/console/mgmt.rs
@@ -13,10 +13,16 @@ use tracing::{error, info, info_span, Instrument};
 static CPLANE_WAITERS: Lazy<Waiters<ComputeReady>> = Lazy::new(Default::default);

 /// Give caller an opportunity to wait for the cloud's reply.
-pub fn get_waiter(
+pub async fn with_waiter<R, T, E>(
    psql_session_id: impl Into<String>,
-) -> Result<Waiter<'static, ComputeReady>, waiters::RegisterError> {
-    CPLANE_WAITERS.register(psql_session_id.into())
+    action: impl FnOnce(Waiter<'static, ComputeReady>) -> R,
+) -> Result<T, E>
+where
+    R: std::future::Future<Output = Result<T, E>>,
+    E: From<waiters::RegisterError>,
+{
+    let waiter = CPLANE_WAITERS.register(psql_session_id.into())?;
+    action(waiter).await
 }

 pub fn notify(psql_session_id: &str, msg: ComputeReady) -> Result<(), waiters::NotifyError> {
@@ -71,7 +77,7 @@ async fn handle_connection(socket: TcpStream) -> Result<(), QueryError> {
 }

 /// A message received by `mgmt` when a compute node is ready.
-pub type ComputeReady = DatabaseInfo;
+pub type ComputeReady = Result<DatabaseInfo, String>;

 // TODO: replace with an http-based protocol.
 struct MgmtHandler;
@@ -96,7 +102,7 @@ fn try_process_query(pgb: &mut PostgresBackendTCP, query: &str) -> Result<(), Qu
    let _enter = span.enter();
    info!("got response: {:?}", resp.result);

-    match notify(resp.session_id, resp.result) {
+    match notify(resp.session_id, Ok(resp.result)) {
        Ok(()) => {
            pgb.write_message_noflush(&SINGLE_COL_ROWDESC)?
                .write_message_noflush(&BeMessage::DataRow(&[Some(b"ok")]))?
--- a/proxy/src/console/provider.rs
+++ b/proxy/src/console/provider.rs
@@ -21,7 +21,7 @@ use tracing::info;

 pub mod errors {
    use crate::{
-        error::{io_error, ReportableError, UserFacingError},
+        error::{io_error, UserFacingError},
        http,
        proxy::retry::ShouldRetry,
    };
@@ -56,15 +56,6 @@ pub mod errors {
        }
    }

-    impl ReportableError for ApiError {
-        fn get_error_type(&self) -> crate::error::ErrorKind {
-            match self {
-                ApiError::Console { .. } => crate::error::ErrorKind::ControlPlane,
-                ApiError::Transport(_) => crate::error::ErrorKind::ControlPlane,
-            }
-        }
-    }
-
    impl UserFacingError for ApiError {
        fn to_string_client(&self) -> String {
            use ApiError::*;
@@ -149,15 +140,6 @@ pub mod errors {
        }
    }

-    impl ReportableError for GetAuthInfoError {
-        fn get_error_type(&self) -> crate::error::ErrorKind {
-            match self {
-                GetAuthInfoError::BadSecret => crate::error::ErrorKind::ControlPlane,
-                GetAuthInfoError::ApiError(_) => crate::error::ErrorKind::ControlPlane,
-            }
-        }
-    }
-
    impl UserFacingError for GetAuthInfoError {
        fn to_string_client(&self) -> String {
            use GetAuthInfoError::*;
@@ -199,16 +181,6 @@ pub mod errors {
        }
    }

-    impl ReportableError for WakeComputeError {
-        fn get_error_type(&self) -> crate::error::ErrorKind {
-            match self {
-                WakeComputeError::BadComputeAddress(_) => crate::error::ErrorKind::ControlPlane,
-                WakeComputeError::ApiError(e) => e.get_error_type(),
-                WakeComputeError::TimeoutError => crate::error::ErrorKind::RateLimit,
-            }
-        }
-    }
-
    impl UserFacingError for WakeComputeError {
        fn to_string_client(&self) -> String {
            use WakeComputeError::*;
@@ -263,7 +235,7 @@ pub struct NodeInfo {

 pub type NodeInfoCache = TimedLru<SmolStr, NodeInfo>;
 pub type CachedNodeInfo = Cached<&'static NodeInfoCache>;
-pub type CachedRoleSecret = Cached<&'static ProjectInfoCacheImpl, Option<AuthSecret>>;
+pub type CachedRoleSecret = Cached<&'static ProjectInfoCacheImpl, AuthSecret>;
 pub type CachedAllowedIps = Cached<&'static ProjectInfoCacheImpl, Arc<Vec<SmolStr>>>;

 /// This will allocate per each call, but the http requests alone
@@ -276,75 +248,23 @@ pub trait Api {
    async fn get_role_secret(
        &self,
        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
-    ) -> Result<CachedRoleSecret, errors::GetAuthInfoError>;
+        creds: &ComputeUserInfo,
+    ) -> Result<Option<CachedRoleSecret>, errors::GetAuthInfoError>;

    async fn get_allowed_ips(
        &self,
        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
+        creds: &ComputeUserInfo,
    ) -> Result<CachedAllowedIps, errors::GetAuthInfoError>;

    /// Wake up the compute node and return the corresponding connection info.
    async fn wake_compute(
        &self,
        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
+        creds: &ComputeUserInfo,
    ) -> Result<CachedNodeInfo, errors::WakeComputeError>;
 }

-#[derive(Clone)]
-pub enum ConsoleBackend {
-    /// Current Cloud API (V2).
-    Console(neon::Api),
-    /// Local mock of Cloud API (V2).
-    #[cfg(feature = "testing")]
-    Postgres(mock::Api),
-}
-
-#[async_trait]
-impl Api for ConsoleBackend {
-    async fn get_role_secret(
-        &self,
-        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
-    ) -> Result<CachedRoleSecret, errors::GetAuthInfoError> {
-        use ConsoleBackend::*;
-        match self {
-            Console(api) => api.get_role_secret(ctx, user_info).await,
-            #[cfg(feature = "testing")]
-            Postgres(api) => api.get_role_secret(ctx, user_info).await,
-        }
-    }
-
-    async fn get_allowed_ips(
-        &self,
-        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
-    ) -> Result<CachedAllowedIps, errors::GetAuthInfoError> {
-        use ConsoleBackend::*;
-        match self {
-            Console(api) => api.get_allowed_ips(ctx, user_info).await,
-            #[cfg(feature = "testing")]
-            Postgres(api) => api.get_allowed_ips(ctx, user_info).await,
-        }
-    }
-
-    async fn wake_compute(
-        &self,
-        ctx: &mut RequestMonitoring,
-        user_info: &ComputeUserInfo,
-    ) -> Result<CachedNodeInfo, errors::WakeComputeError> {
-        use ConsoleBackend::*;
-
-        match self {
-            Console(api) => api.wake_compute(ctx, user_info).await,
-            #[cfg(feature = "testing")]
-            Postgres(api) => api.wake_compute(ctx, user_info).await,
-        }
-    }
-}
-
 /// Various caches for [`console`](super).
 pub struct ApiCaches {
    /// Cache for the `wake_compute` API method.
--- a/proxy/src/console/provider/mock.rs
+++ b/proxy/src/console/provider/mock.rs
@@ -150,10 +150,12 @@ impl super::Api for Api {
        &self,
        _ctx: &mut RequestMonitoring,
        user_info: &ComputeUserInfo,
-    ) -> Result<CachedRoleSecret, GetAuthInfoError> {
-        Ok(CachedRoleSecret::new_uncached(
-            self.do_get_auth_info(user_info).await?.secret,
-        ))
+    ) -> Result<Option<CachedRoleSecret>, GetAuthInfoError> {
+        Ok(self
+            .do_get_auth_info(user_info)
+            .await?
+            .secret
+            .map(CachedRoleSecret::new_uncached))
    }

    async fn get_allowed_ips(
--- a/proxy/src/console/provider/neon.rs
+++ b/proxy/src/console/provider/neon.rs
@@ -86,14 +86,9 @@ impl Api {
                },
            };

-            let secret = if body.role_secret.is_empty() {
-                None
-            } else {
-                let secret = scram::ServerSecret::parse(&body.role_secret)
-                    .map(AuthSecret::Scram)
-                    .ok_or(GetAuthInfoError::BadSecret)?;
-                Some(secret)
-            };
+            let secret = scram::ServerSecret::parse(&body.role_secret)
+                .map(AuthSecret::Scram)
+                .ok_or(GetAuthInfoError::BadSecret)?;
            let allowed_ips = body
                .allowed_ips
                .into_iter()
@@ -102,7 +97,7 @@ impl Api {
                .collect_vec();
            ALLOWED_IPS_NUMBER.observe(allowed_ips.len() as f64);
            Ok(AuthInfo {
-                secret,
+                secret: Some(secret),
                allowed_ips,
                project_id: body.project_id.map(SmolStr::from),
            })
@@ -177,28 +172,26 @@ impl super::Api for Api {
        &self,
        ctx: &mut RequestMonitoring,
        user_info: &ComputeUserInfo,
-    ) -> Result<CachedRoleSecret, GetAuthInfoError> {
+    ) -> Result<Option<CachedRoleSecret>, GetAuthInfoError> {
        let ep = &user_info.endpoint;
        let user = &user_info.user;
        if let Some(role_secret) = self.caches.project_info.get_role_secret(ep, user) {
-            return Ok(role_secret);
+            return Ok(Some(role_secret));
        }
        let auth_info = self.do_get_auth_info(ctx, user_info).await?;
-        if let Some(project_id) = auth_info.project_id {
-            self.caches.project_info.insert_role_secret(
-                &project_id,
-                ep,
-                user,
-                auth_info.secret.clone(),
-            );
-            self.caches.project_info.insert_allowed_ips(
-                &project_id,
-                ep,
-                Arc::new(auth_info.allowed_ips),
-            );
+        let project_id = auth_info.project_id.unwrap_or(ep.clone());
+        if let Some(secret) = &auth_info.secret {
+            self.caches
+                .project_info
+                .insert_role_secret(&project_id, ep, user, secret.clone())
        }
+        self.caches.project_info.insert_allowed_ips(
+            &project_id,
+            ep,
+            Arc::new(auth_info.allowed_ips),
+        );
        // When we just got a secret, we don't need to invalidate it.
-        Ok(Cached::new_uncached(auth_info.secret))
+        Ok(auth_info.secret.map(Cached::new_uncached))
    }

    async fn get_allowed_ips(
@@ -219,17 +212,15 @@ impl super::Api for Api {
        let auth_info = self.do_get_auth_info(ctx, user_info).await?;
        let allowed_ips = Arc::new(auth_info.allowed_ips);
        let user = &user_info.user;
-        if let Some(project_id) = auth_info.project_id {
-            self.caches.project_info.insert_role_secret(
-                &project_id,
-                ep,
-                user,
-                auth_info.secret.clone(),
-            );
+        let project_id = auth_info.project_id.unwrap_or(ep.clone());
+        if let Some(secret) = &auth_info.secret {
            self.caches
                .project_info
-                .insert_allowed_ips(&project_id, ep, allowed_ips.clone());
+                .insert_role_secret(&project_id, ep, user, secret.clone())
        }
+        self.caches
+            .project_info
+            .insert_allowed_ips(&project_id, ep, allowed_ips.clone());
        Ok(Cached::new_uncached(allowed_ips))
    }

--- a/proxy/src/context.rs
+++ b/proxy/src/context.rs
@@ -38,7 +38,6 @@ pub struct RequestMonitoring {
    // This sender is here to keep the request monitoring channel open while requests are taking place.
    sender: Option<mpsc::UnboundedSender<RequestMonitoring>>,
    pub latency_timer: LatencyTimer,
-    root_span: tracing::Span,
 }

 impl RequestMonitoring {
@@ -47,7 +46,6 @@ impl RequestMonitoring {
        peer_addr: IpAddr,
        protocol: &'static str,
        region: &'static str,
-        root_span: tracing::Span,
    ) -> Self {
        Self {
            peer_addr,
@@ -66,19 +64,12 @@ impl RequestMonitoring {

            sender: LOG_CHAN.get().and_then(|tx| tx.upgrade()),
            latency_timer: LatencyTimer::new(protocol),
-            root_span,
        }
    }

    #[cfg(test)]
    pub fn test() -> Self {
-        RequestMonitoring::new(
-            Uuid::now_v7(),
-            [127, 0, 0, 1].into(),
-            "test",
-            "test",
-            tracing::Span::none(),
-        )
+        RequestMonitoring::new(Uuid::now_v7(), [127, 0, 0, 1].into(), "test", "test")
    }

    pub fn console_application_name(&self) -> String {
@@ -96,10 +87,7 @@ impl RequestMonitoring {
    }

    pub fn set_endpoint_id(&mut self, endpoint_id: Option<SmolStr>) {
-        if let (None, Some(ep)) = (self.endpoint_id.as_ref(), endpoint_id) {
-            self.root_span.record("ep", &*ep);
-            self.endpoint_id = Some(ep)
-        }
+        self.endpoint_id = endpoint_id.or_else(|| self.endpoint_id.clone());
    }

    pub fn set_application(&mut self, app: Option<SmolStr>) {
@@ -114,10 +102,6 @@ impl RequestMonitoring {
        self.success = true;
    }

-    pub fn error(&mut self, err: ErrorKind) {
-        self.error_kind = Some(err);
-    }
-
    pub fn log(&mut self) {
        if let Some(tx) = self.sender.take() {
            let _: Result<(), _> = tx.send(self.clone());
--- a/proxy/src/error.rs
+++ b/proxy/src/error.rs
@@ -17,16 +17,19 @@ pub fn log_error<E: fmt::Display>(e: E) -> E {
 /// NOTE: This trait should not be implemented for [`anyhow::Error`], since it
 /// is way too convenient and tends to proliferate all across the codebase,
 /// ultimately leading to accidental leaks of sensitive data.
-pub trait UserFacingError: ReportableError {
+pub trait UserFacingError: fmt::Display {
    /// Format the error for client, stripping all sensitive info.
    ///
    /// Although this might be a no-op for many types, it's highly
    /// recommended to override the default impl in case error type
    /// contains anything sensitive: various IDs, IP addresses etc.
-    fn to_string_client(&self) -> String;
+    #[inline(always)]
+    fn to_string_client(&self) -> String {
+        self.to_string()
+    }
 }

-#[derive(Clone, Copy)]
+#[derive(Clone)]
 pub enum ErrorKind {
    /// Wrong password, unknown endpoint, protocol violation, etc...
    User,
@@ -59,7 +62,3 @@ impl ErrorKind {
        }
    }
 }
-
-pub trait ReportableError: fmt::Display + Send + 'static {
-    fn get_error_type(&self) -> ErrorKind;
-}
--- a/proxy/src/lib.rs
+++ b/proxy/src/lib.rs
@@ -26,7 +26,6 @@ pub mod redis;
 pub mod sasl;
 pub mod scram;
 pub mod serverless;
-pub mod state_machine;
 pub mod stream;
 pub mod url;
 pub mod usage_metrics;
--- a/proxy/src/proxy.rs
+++ b/proxy/src/proxy.rs
@@ -2,32 +2,38 @@
 mod tests;

 pub mod connect_compute;
-pub mod handshake;
-pub mod pass;
 pub mod retry;
-pub mod wake_compute;

 use crate::{
-    cancellation::CancelMap,
-    config::{ProxyConfig, TlsConfig},
+    auth,
+    cancellation::{self, CancelMap},
+    compute,
+    config::{AuthenticationConfig, ProxyConfig, TlsConfig},
+    console::messages::MetricsAuxInfo,
    context::RequestMonitoring,
-    metrics::{NUM_CLIENT_CONNECTION_GAUGE, NUM_CONNECTION_REQUESTS_GAUGE},
+    metrics::{
+        NUM_BYTES_PROXIED_COUNTER, NUM_BYTES_PROXIED_PER_CLIENT_COUNTER,
+        NUM_CLIENT_CONNECTION_GAUGE, NUM_CONNECTION_REQUESTS_GAUGE,
+    },
    protocol2::WithClientIp,
-    proxy::handshake::NeedsHandshake,
    rate_limiter::EndpointRateLimiter,
-    state_machine::{DynStage, StageResult},
-    stream::Stream,
+    stream::{PqStream, Stream},
+    usage_metrics::{Ids, USAGE_METRICS},
 };
-use anyhow::Context;
+use anyhow::{bail, Context};
+use futures::TryFutureExt;
 use itertools::Itertools;
 use once_cell::sync::OnceCell;
-use pq_proto::StartupMessageParams;
+use pq_proto::{BeMessage as Be, FeStartupPacket, StartupMessageParams};
 use regex::Regex;
 use smol_str::SmolStr;
 use std::sync::Arc;
-use tokio::io::{AsyncRead, AsyncWrite};
+use tokio::io::{AsyncRead, AsyncWrite, AsyncWriteExt};
 use tokio_util::sync::CancellationToken;
 use tracing::{error, info, info_span, Instrument};
+use utils::measured_stream::MeasuredStream;
+
+use self::connect_compute::{connect_to_compute, TcpMechanism};

 const ERR_INSECURE_CONNECTION: &str = "connection is insecure (try using `sslmode=require`)";
 const ERR_PROTO_VIOLATION: &str = "protocol violation";
@@ -73,64 +79,45 @@ pub async fn task_main(
        let cancel_map = Arc::clone(&cancel_map);
        let endpoint_rate_limiter = endpoint_rate_limiter.clone();

-        let root_span = info_span!(
-            "handle_client",
-            ?session_id,
-            peer_addr = tracing::field::Empty,
-            ep = tracing::field::Empty,
-        );
-        let root_span2 = root_span.clone();
-
        connections.spawn(
            async move {
                info!("accepted postgres client connection");

                let mut socket = WithClientIp::new(socket);
                let mut peer_addr = peer_addr.ip();
-                match socket.wait_for_addr().await {
-                    Err(e) => {
-                        error!("IO error: {e:#}");
-                        return;
-                    }
-                    Ok(Some(addr)) => {
-                        peer_addr = addr.ip();
-                        root_span2.record("peer_addr", &tracing::field::display(addr));
-                    }
-                    Ok(None) if config.require_client_ip => {
-                        error!("missing required client IP");
-                        return;
-                    }
-                    Ok(None) => {}
-                };
+                if let Some(addr) = socket.wait_for_addr().await? {
+                    peer_addr = addr.ip();
+                    tracing::Span::current().record("peer_addr", &tracing::field::display(addr));
+                } else if config.require_client_ip {
+                    bail!("missing required client IP");
+                }

-                let ctx = RequestMonitoring::new(
-                    session_id,
-                    peer_addr,
-                    "tcp",
-                    &config.region,
-                    root_span2,
-                );
+                let mut ctx = RequestMonitoring::new(session_id, peer_addr, "tcp", &config.region);

-                if let Err(e) = socket
+                socket
                    .inner
                    .set_nodelay(true)
-                    .context("failed to set socket option")
-                {
-                    error!("could not set nodelay: {e:#}");
-                    return;
-                }
+                    .context("failed to set socket option")?;

                handle_client(
                    config,
-                    ctx,
-                    cancel_map,
+                    &mut ctx,
+                    &cancel_map,
                    socket,
                    ClientMode::Tcp,
                    endpoint_rate_limiter,
                )
-                .await;
+                .await
            }
-            .instrument(root_span),
+            .instrument(info_span!(
+                "handle_client",
+                ?session_id,
+                peer_addr = tracing::field::Empty
+            ))
+            .unwrap_or_else(move |e| {
+                // Acknowledge that the task has finished with an error.
+                error!(?session_id, "per-client task finished with an error: {e:#}");
+            }),
        );
    }

@@ -150,14 +137,14 @@ pub enum ClientMode {

 /// Abstracts the logic of handling TCP vs WS clients
 impl ClientMode {
-    pub fn allow_cleartext(&self) -> bool {
+    fn allow_cleartext(&self) -> bool {
        match self {
            ClientMode::Tcp => false,
            ClientMode::Websockets { .. } => true,
        }
    }

-    pub fn allow_self_signed_compute(&self, config: &ProxyConfig) -> bool {
+    fn allow_self_signed_compute(&self, config: &ProxyConfig) -> bool {
        match self {
            ClientMode::Tcp => config.allow_self_signed_compute,
            ClientMode::Websockets { .. } => false,
@@ -180,14 +167,14 @@ impl ClientMode {
    }
 }

-pub async fn handle_client<S: AsyncRead + AsyncWrite + Unpin + 'static + Send>(
+pub async fn handle_client<S: AsyncRead + AsyncWrite + Unpin>(
    config: &'static ProxyConfig,
-    ctx: RequestMonitoring,
-    cancel_map: Arc<CancelMap>,
+    ctx: &mut RequestMonitoring,
+    cancel_map: &CancelMap,
    stream: S,
    mode: ClientMode,
    endpoint_rate_limiter: Arc<EndpointRateLimiter>,
-) {
+) -> anyhow::Result<()> {
    info!(
        protocol = ctx.protocol,
        "handling interactive connection from client"
@@ -201,26 +188,311 @@ pub async fn handle_client<S: AsyncRead + AsyncWrite + Unpin + 'static + Send>(
        .with_label_values(&[proto])
        .guard();

-    let mut stage = Box::new(NeedsHandshake {
-        stream,
-        config,
-        cancel_map,
-        mode,
-        endpoint_rate_limiter,
-        ctx,
-    }) as DynStage;
+    let tls = config.tls_config.as_ref();

-    while let StageResult::Run(handle) = stage.run() {
-        stage = match handle.await.expect("tasks should not panic") {
-            Ok(s) => s,
-            Err(e) => {
-                e.finish().await;
-                break;
+    let pause = ctx.latency_timer.pause();
+    let do_handshake = handshake(stream, mode.handshake_tls(tls), cancel_map);
+    let (mut stream, params) = match do_handshake.await? {
+        Some(x) => x,
+        None => return Ok(()), // it's a cancellation request
+    };
+    drop(pause);
+
+    // Extract credentials which we're going to use for auth.
+    let user_info = {
+        let hostname = mode.hostname(stream.get_ref());
+
+        let common_names = tls.map(|tls| &tls.common_names);
+        let result = config
+            .auth_backend
+            .as_ref()
+            .map(|_| {
+                auth::ComputeUserInfoMaybeEndpoint::parse(ctx, &params, hostname, common_names)
+            })
+            .transpose();
+
+        match result {
+            Ok(user_info) => user_info,
+            Err(e) => stream.throw_error(e).await?,
+        }
+    };
+
+    ctx.set_endpoint_id(user_info.get_endpoint());
+
+    let client = Client::new(
+        stream,
+        user_info,
+        &params,
+        mode.allow_self_signed_compute(config),
+        endpoint_rate_limiter,
+    );
+    cancel_map
+        .with_session(|session| {
+            client.connect_to_db(ctx, session, mode, &config.authentication_config)
+        })
+        .await
+}
+
+/// Establish a (most probably, secure) connection with the client.
+/// For better testing experience, `stream` can be any object satisfying the traits.
+/// It's easier to work with owned `stream` here as we need to upgrade it to TLS;
+/// we also take an extra care of propagating only the select handshake errors to client.
+#[tracing::instrument(skip_all)]
+async fn handshake<S: AsyncRead + AsyncWrite + Unpin>(
+    stream: S,
+    mut tls: Option<&TlsConfig>,
+    cancel_map: &CancelMap,
+) -> anyhow::Result<Option<(PqStream<Stream<S>>, StartupMessageParams)>> {
+    // Client may try upgrading to each protocol only once
+    let (mut tried_ssl, mut tried_gss) = (false, false);
+
+    let mut stream = PqStream::new(Stream::from_raw(stream));
+    loop {
+        let msg = stream.read_startup_packet().await?;
+        info!("received {msg:?}");
+
+        use FeStartupPacket::*;
+        match msg {
+            SslRequest => match stream.get_ref() {
+                Stream::Raw { .. } if !tried_ssl => {
+                    tried_ssl = true;
+
+                    // We can't perform TLS handshake without a config
+                    let enc = tls.is_some();
+                    stream.write_message(&Be::EncryptionResponse(enc)).await?;
+                    if let Some(tls) = tls.take() {
+                        // Upgrade raw stream into a secure TLS-backed stream.
+                        // NOTE: We've consumed `tls`; this fact will be used later.
+
+                        let (raw, read_buf) = stream.into_inner();
+                        // TODO: Normally, client doesn't send any data before
+                        // server says TLS handshake is ok and read_buf is empy.
+                        // However, you could imagine pipelining of postgres
+                        // SSLRequest + TLS ClientHello in one hunk similar to
+                        // pipelining in our node js driver. We should probably
+                        // support that by chaining read_buf with the stream.
+                        if !read_buf.is_empty() {
+                            bail!("data is sent before server replied with EncryptionResponse");
+                        }
+                        let tls_stream = raw.upgrade(tls.to_server_config()).await?;
+
+                        let (_, tls_server_end_point) = tls
+                            .cert_resolver
+                            .resolve(tls_stream.get_ref().1.server_name())
+                            .context("missing certificate")?;
+
+                        stream = PqStream::new(Stream::Tls {
+                            tls: Box::new(tls_stream),
+                            tls_server_end_point,
+                        });
+                    }
+                }
+                _ => bail!(ERR_PROTO_VIOLATION),
+            },
+            GssEncRequest => match stream.get_ref() {
+                Stream::Raw { .. } if !tried_gss => {
+                    tried_gss = true;
+
+                    // Currently, we don't support GSSAPI
+                    stream.write_message(&Be::EncryptionResponse(false)).await?;
+                }
+                _ => bail!(ERR_PROTO_VIOLATION),
+            },
+            StartupMessage { params, .. } => {
+                // Check that the config has been consumed during upgrade
+                // OR we didn't provide it at all (for dev purposes).
+                if tls.is_some() {
+                    stream.throw_error_str(ERR_INSECURE_CONNECTION).await?;
+                }
+
+                info!(session_type = "normal", "successful handshake");
+                break Ok(Some((stream, params)));
+            }
+            CancelRequest(cancel_key_data) => {
+                cancel_map.cancel_session(cancel_key_data).await?;
+
+                info!(session_type = "cancellation", "successful handshake");
+                break Ok(None);
            }
        }
    }
 }

+/// Finish client connection initialization: confirm auth success, send params, etc.
+#[tracing::instrument(skip_all)]
+async fn prepare_client_connection(
+    node: &compute::PostgresConnection,
+    session: cancellation::Session<'_>,
+    stream: &mut PqStream<impl AsyncRead + AsyncWrite + Unpin>,
+) -> anyhow::Result<()> {
+    // Register compute's query cancellation token and produce a new, unique one.
+    // The new token (cancel_key_data) will be sent to the client.
+    let cancel_key_data = session.enable_query_cancellation(node.cancel_closure.clone());
+
+    // Forward all postgres connection params to the client.
+    // Right now the implementation is very hacky and inefficent (ideally,
+    // we don't need an intermediate hashmap), but at least it should be correct.
+    for (name, value) in &node.params {
+        // TODO: Theoretically, this could result in a big pile of params...
+        stream.write_message_noflush(&Be::ParameterStatus {
+            name: name.as_bytes(),
+            value: value.as_bytes(),
+        })?;
+    }
+
+    stream
+        .write_message_noflush(&Be::BackendKeyData(cancel_key_data))?
+        .write_message(&Be::ReadyForQuery)
+        .await?;
+
+    Ok(())
+}
+
+/// Forward bytes in both directions (client <-> compute).
+#[tracing::instrument(skip_all)]
+pub async fn proxy_pass(
+    ctx: &mut RequestMonitoring,
+    client: impl AsyncRead + AsyncWrite + Unpin,
+    compute: impl AsyncRead + AsyncWrite + Unpin,
+    aux: MetricsAuxInfo,
+) -> anyhow::Result<()> {
+    ctx.set_success();
+    ctx.log();
+
+    let usage = USAGE_METRICS.register(Ids {
+        endpoint_id: aux.endpoint_id.clone(),
+        branch_id: aux.branch_id.clone(),
+    });
+
+    let m_sent = NUM_BYTES_PROXIED_COUNTER.with_label_values(&["tx"]);
+    let m_sent2 = NUM_BYTES_PROXIED_PER_CLIENT_COUNTER.with_label_values(&aux.traffic_labels("tx"));
+    let mut client = MeasuredStream::new(
+        client,
+        |_| {},
+        |cnt| {
+            // Number of bytes we sent to the client (outbound).
+            m_sent.inc_by(cnt as u64);
+            m_sent2.inc_by(cnt as u64);
+            usage.record_egress(cnt as u64);
+        },
+    );
+
+    let m_recv = NUM_BYTES_PROXIED_COUNTER.with_label_values(&["rx"]);
+    let m_recv2 = NUM_BYTES_PROXIED_PER_CLIENT_COUNTER.with_label_values(&aux.traffic_labels("rx"));
+    let mut compute = MeasuredStream::new(
+        compute,
+        |_| {},
+        |cnt| {
+            // Number of bytes the client sent to the compute node (inbound).
+            m_recv.inc_by(cnt as u64);
+            m_recv2.inc_by(cnt as u64);
+        },
+    );
+
+    // Starting from here we only proxy the client's traffic.
+    info!("performing the proxy pass...");
+    let _ = tokio::io::copy_bidirectional(&mut client, &mut compute).await?;
+
+    Ok(())
+}
+
+/// Thin connection context.
+struct Client<'a, S> {
+    /// The underlying libpq protocol stream.
+    stream: PqStream<Stream<S>>,
+    /// Client credentials that we care about.
+    user_info: auth::BackendType<'a, auth::ComputeUserInfoMaybeEndpoint>,
+    /// KV-dictionary with PostgreSQL connection params.
+    params: &'a StartupMessageParams,
+    /// Allow self-signed certificates (for testing).
+    allow_self_signed_compute: bool,
+    /// Rate limiter for endpoints
+    endpoint_rate_limiter: Arc<EndpointRateLimiter>,
+}
+
+impl<'a, S> Client<'a, S> {
+    /// Construct a new connection context.
+    fn new(
+        stream: PqStream<Stream<S>>,
+        user_info: auth::BackendType<'a, auth::ComputeUserInfoMaybeEndpoint>,
+        params: &'a StartupMessageParams,
+        allow_self_signed_compute: bool,
+        endpoint_rate_limiter: Arc<EndpointRateLimiter>,
+    ) -> Self {
+        Self {
+            stream,
+            user_info,
+            params,
+            allow_self_signed_compute,
+            endpoint_rate_limiter,
+        }
+    }
+}
+
+impl<S: AsyncRead + AsyncWrite + Unpin> Client<'_, S> {
+    /// Let the client authenticate and connect to the designated compute node.
+    // Instrumentation logs endpoint name everywhere. Doesn't work for link
+    // auth; strictly speaking we don't know endpoint name in its case.
+    #[tracing::instrument(name = "", fields(ep = %self.user_info.get_endpoint().unwrap_or_default()), skip_all)]
+    async fn connect_to_db(
+        self,
+        ctx: &mut RequestMonitoring,
+        session: cancellation::Session<'_>,
+        mode: ClientMode,
+        config: &'static AuthenticationConfig,
+    ) -> anyhow::Result<()> {
+        let Self {
+            mut stream,
+            user_info,
+            params,
+            allow_self_signed_compute,
+            endpoint_rate_limiter,
+        } = self;
+
+        // check rate limit
+        if let Some(ep) = user_info.get_endpoint() {
+            if !endpoint_rate_limiter.check(ep) {
+                return stream
+                    .throw_error(auth::AuthError::too_many_connections())
+                    .await;
+            }
+        }
+
+        let user = user_info.get_user().to_owned();
+        let auth_result = match user_info
+            .authenticate(ctx, &mut stream, mode.allow_cleartext(), config)
+            .await
+        {
+            Ok(auth_result) => auth_result,
+            Err(e) => {
+                let db = params.get("database");
+                let app = params.get("application_name");
+                let params_span = tracing::info_span!("", ?user, ?db, ?app);
+
+                return stream.throw_error(e).instrument(params_span).await;
+            }
+        };
+
+        let (mut node_info, user_info) = auth_result;
+
+        node_info.allow_self_signed_compute = allow_self_signed_compute;
+
+        let aux = node_info.aux.clone();
+        let mut node = connect_to_compute(ctx, &TcpMechanism { params }, node_info, &user_info)
+            .or_else(|e| stream.throw_error(e))
+            .await?;
+
+        prepare_client_connection(&node, session, &mut stream).await?;
+        // Before proxy passing, forward to compute whatever data is left in the
+        // PqStream input buffer. Normally there is none, but our serverless npm
+        // driver in pipeline mode sends startup, password and first query
+        // immediately after opening the connection.
+        let (stream, read_buf) = stream.into_inner();
+        node.stream.write_all(&read_buf).await?;
+        proxy_pass(ctx, stream, node.stream, aux).await
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Default)]
 pub struct NeonOptions(Vec<(SmolStr, SmolStr)>);

--- a/proxy/src/proxy/connect_compute.rs
+++ b/proxy/src/proxy/connect_compute.rs
@@ -1,120 +1,20 @@
 use crate::{
    auth,
-    cancellation::{self, Session},
    compute::{self, PostgresConnection},
    console::{self, errors::WakeComputeError, Api},
    context::RequestMonitoring,
    metrics::{bool_to_str, NUM_CONNECTION_FAILURES, NUM_WAKEUP_FAILURES},
-    state_machine::{DynStage, ResultExt, Stage, StageError},
-    stream::{PqStream, Stream},
+    proxy::retry::{retry_after, ShouldRetry},
 };
 use async_trait::async_trait;
 use hyper::StatusCode;
 use pq_proto::StartupMessageParams;
 use std::ops::ControlFlow;
-use tokio::{
-    io::{AsyncRead, AsyncWrite, AsyncWriteExt},
-    time,
-};
+use tokio::time;
 use tracing::{error, info, warn};

-use pq_proto::BeMessage as Be;
-
-use super::{
-    pass::ProxyPass,
-    retry::{retry_after, ShouldRetry},
-};
-
 const CONNECT_TIMEOUT: time::Duration = time::Duration::from_secs(2);

-pub struct NeedsComputeConnection<S> {
-    pub stream: PqStream<Stream<S>>,
-    pub user_info: auth::BackendType<'static, auth::backend::ComputeUserInfo>,
-    pub mechanism: TcpMechanism,
-    pub node_info: console::CachedNodeInfo,
-
-    // monitoring
-    pub ctx: RequestMonitoring,
-    pub cancel_session: Session,
-}
-
-impl<S> Stage for NeedsComputeConnection<S>
-where
-    S: AsyncRead + AsyncWrite + Unpin + Send + 'static,
-{
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("connect_to_compute")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            stream,
-            user_info,
-            mechanism,
-            node_info,
-            mut ctx,
-            cancel_session,
-        } = self;
-
-        let aux = node_info.aux.clone();
-        let (mut node, mut stream) =
-            connect_to_compute(&mut ctx, &mechanism, node_info, &user_info)
-                .await
-                .send_error_to_user(&mut ctx, stream)?;
-
-        prepare_client_connection(&node, &cancel_session, &mut stream)
-            .await
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Disconnect)?;
-
-        // Before proxy passing, forward to compute whatever data is left in the
-        // PqStream input buffer. Normally there is none, but our serverless npm
-        // driver in pipeline mode sends startup, password and first query
-        // immediately after opening the connection.
-        let (stream, read_buf) = stream.into_inner();
-
-        node.stream
-            .write_all(&read_buf)
-            .await
-            .no_user_error(&mut ctx, crate::error::ErrorKind::Disconnect)?;
-
-        Ok(Box::new(ProxyPass {
-            client: stream,
-            compute: node.stream,
-            aux,
-            cancel_session,
-        }))
-    }
-}
-
-/// Finish client connection initialization: confirm auth success, send params, etc.
-#[tracing::instrument(skip_all)]
-async fn prepare_client_connection(
-    node: &compute::PostgresConnection,
-    session: &cancellation::Session,
-    stream: &mut PqStream<impl AsyncRead + AsyncWrite + Unpin>,
-) -> std::io::Result<()> {
-    // Register compute's query cancellation token and produce a new, unique one.
-    // The new token (cancel_key_data) will be sent to the client.
-    let cancel_key_data = session.enable_query_cancellation(node.cancel_closure.clone());
-
-    // Forward all postgres connection params to the client.
-    // Right now the implementation is very hacky and inefficent (ideally,
-    // we don't need an intermediate hashmap), but at least it should be correct.
-    for (name, value) in &node.params {
-        // TODO: Theoretically, this could result in a big pile of params...
-        stream.write_message_noflush(&Be::ParameterStatus {
-            name: name.as_bytes(),
-            value: value.as_bytes(),
-        })?;
-    }
-
-    stream
-        .write_message_noflush(&Be::BackendKeyData(cancel_key_data))?
-        .write_message(&Be::ReadyForQuery)
-        .await?;
-
-    Ok(())
-}
-
 /// If we couldn't connect, a cached connection info might be to blame
 /// (e.g. the compute node's address might've changed at the wrong time).
 /// Invalidate the cache entry (if any) to prevent subsequent errors.
@@ -163,13 +63,13 @@ pub trait ConnectMechanism {
    fn update_connect_config(&self, conf: &mut compute::ConnCfg);
 }

-pub struct TcpMechanism {
+pub struct TcpMechanism<'a> {
    /// KV-dictionary with PostgreSQL connection params.
-    pub params: StartupMessageParams,
+    pub params: &'a StartupMessageParams,
 }

 #[async_trait]
-impl ConnectMechanism for TcpMechanism {
+impl ConnectMechanism for TcpMechanism<'_> {
    type Connection = PostgresConnection;
    type ConnectError = compute::ConnectionError;
    type Error = compute::ConnectionError;
@@ -184,7 +84,7 @@ impl ConnectMechanism for TcpMechanism {
    }

    fn update_connect_config(&self, config: &mut compute::ConnCfg) {
-        config.set_startup_params(&self.params);
+        config.set_startup_params(self.params);
    }
 }

@@ -260,6 +160,8 @@ where
    let node_info = loop {
        let wake_res = match user_info {
            auth::BackendType::Console(api, user_info) => api.wake_compute(ctx, user_info).await,
+            #[cfg(feature = "testing")]
+            auth::BackendType::Postgres(api, user_info) => api.wake_compute(ctx, user_info).await,
            // nothing to do?
            auth::BackendType::Link(_) => return Err(err.into()),
            // test backend
--- a/proxy/src/proxy/handshake.rs
+++ b/proxy/src/proxy/handshake.rs
@@ -1,203 +0,0 @@
-use crate::{
-    auth::{self, backend::NeedsAuthentication},
-    cancellation::CancelMap,
-    config::{ProxyConfig, TlsConfig},
-    context::RequestMonitoring,
-    error::ReportableError,
-    proxy::{ERR_INSECURE_CONNECTION, ERR_PROTO_VIOLATION},
-    rate_limiter::EndpointRateLimiter,
-    state_machine::{DynStage, Finished, ResultExt, Stage, StageError},
-    stream::{PqStream, Stream, StreamUpgradeError},
-};
-use anyhow::{anyhow, Context};
-use pq_proto::{BeMessage as Be, FeStartupPacket, StartupMessageParams};
-use std::{io, sync::Arc};
-use thiserror::Error;
-use tokio::io::{AsyncRead, AsyncWrite};
-use tracing::{error, info};
-
-use super::ClientMode;
-
-pub struct NeedsHandshake<S> {
-    pub stream: S,
-    pub config: &'static ProxyConfig,
-    pub cancel_map: Arc<CancelMap>,
-    pub mode: ClientMode,
-    pub endpoint_rate_limiter: Arc<EndpointRateLimiter>,
-
-    // monitoring
-    pub ctx: RequestMonitoring,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsHandshake<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("handshake")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            stream,
-            config,
-            cancel_map,
-            mode,
-            endpoint_rate_limiter,
-            mut ctx,
-        } = self;
-
-        let tls = config.tls_config.as_ref();
-
-        let pause_timer = ctx.latency_timer.pause();
-        let handshake = handshake(stream, mode.handshake_tls(tls), &cancel_map).await;
-        drop(pause_timer);
-
-        let (stream, params) = match handshake {
-            Err(err) => {
-                // TODO: proper handling
-                error!("could not complete handshake: {err:#}");
-                return Err(StageError::Done);
-            }
-            // cancellation
-            Ok(None) => return Ok(Box::new(Finished)),
-            Ok(Some(s)) => s,
-        };
-
-        let hostname = mode.hostname(stream.get_ref());
-
-        let common_names = tls.map(|tls| &tls.common_names);
-        let (creds, stream) = config
-            .auth_backend
-            .as_ref()
-            .map(|_| {
-                auth::ComputeUserInfoMaybeEndpoint::parse(&mut ctx, &params, hostname, common_names)
-            })
-            .transpose()
-            .send_error_to_user(&mut ctx, stream)?;
-
-        ctx.set_endpoint_id(creds.get_endpoint());
-
-        Ok(Box::new(NeedsAuthentication {
-            stream,
-            creds,
-            params,
-            endpoint_rate_limiter,
-            mode,
-            config,
-
-            ctx,
-            cancel_session: cancel_map.get_session(),
-        }))
-    }
-}
-
-#[derive(Error, Debug)]
-pub enum HandshakeError {
-    #[error("client disconnected: {0}")]
-    ClientIO(#[from] io::Error),
-    #[error("protocol violation: {0}")]
-    ProtocolError(#[from] anyhow::Error),
-    #[error("could not initiate tls connection: {0}")]
-    TLSError(#[from] StreamUpgradeError),
-    #[error("could not cancel connection: {0}")]
-    Cancel(anyhow::Error),
-}
-
-impl ReportableError for HandshakeError {
-    fn get_error_type(&self) -> crate::error::ErrorKind {
-        match self {
-            HandshakeError::ClientIO(_) => crate::error::ErrorKind::Disconnect,
-            HandshakeError::ProtocolError(_) => crate::error::ErrorKind::User,
-            HandshakeError::TLSError(_) => crate::error::ErrorKind::User,
-            HandshakeError::Cancel(_) => crate::error::ErrorKind::Compute,
-        }
-    }
-}
-
-type SuccessfulHandshake<S> = (PqStream<Stream<S>>, StartupMessageParams);
-
-/// Establish a (most probably, secure) connection with the client.
-/// For better testing experience, `stream` can be any object satisfying the traits.
-/// It's easier to work with owned `stream` here as we need to upgrade it to TLS;
-/// we also take an extra care of propagating only the select handshake errors to client.
-pub async fn handshake<S: AsyncRead + AsyncWrite + Unpin>(
-    stream: S,
-    mut tls: Option<&TlsConfig>,
-    cancel_map: &CancelMap,
-) -> Result<Option<SuccessfulHandshake<S>>, HandshakeError> {
-    // Client may try upgrading to each protocol only once
-    let (mut tried_ssl, mut tried_gss) = (false, false);
-
-    let mut stream = PqStream::new(Stream::from_raw(stream));
-    loop {
-        let msg = stream.read_startup_packet().await?;
-        info!("received {msg:?}");
-
-        use FeStartupPacket::*;
-        match msg {
-            SslRequest => match stream.get_ref() {
-                Stream::Raw { .. } if !tried_ssl => {
-                    tried_ssl = true;
-
-                    // We can't perform TLS handshake without a config
-                    let enc = tls.is_some();
-                    stream.write_message(&Be::EncryptionResponse(enc)).await?;
-                    if let Some(tls) = tls.take() {
-                        // Upgrade raw stream into a secure TLS-backed stream.
-                        // NOTE: We've consumed `tls`; this fact will be used later.
-
-                        let (raw, read_buf) = stream.into_inner();
-                        // TODO: Normally, client doesn't send any data before
-                        // server says TLS handshake is ok and read_buf is empy.
-                        // However, you could imagine pipelining of postgres
-                        // SSLRequest + TLS ClientHello in one hunk similar to
-                        // pipelining in our node js driver. We should probably
-                        // support that by chaining read_buf with the stream.
-                        if !read_buf.is_empty() {
-                            return Err(HandshakeError::ProtocolError(anyhow!(
-                                "data is sent before server replied with EncryptionResponse"
-                            )));
-                        }
-                        let tls_stream = raw.upgrade(tls.to_server_config()).await?;
-
-                        let (_, tls_server_end_point) = tls
-                            .cert_resolver
-                            .resolve(tls_stream.get_ref().1.server_name())
-                            .context("missing certificate")?;
-
-                        stream = PqStream::new(Stream::Tls {
-                            tls: Box::new(tls_stream),
-                            tls_server_end_point,
-                        });
-                    }
-                }
-                _ => return Err(HandshakeError::ProtocolError(anyhow!(ERR_PROTO_VIOLATION))),
-            },
-            GssEncRequest => match stream.get_ref() {
-                Stream::Raw { .. } if !tried_gss => {
-                    tried_gss = true;
-
-                    // Currently, we don't support GSSAPI
-                    stream.write_message(&Be::EncryptionResponse(false)).await?;
-                }
-                _ => return Err(HandshakeError::ProtocolError(anyhow!(ERR_PROTO_VIOLATION))),
-            },
-            StartupMessage { params, .. } => {
-                // Check that the config has been consumed during upgrade
-                // OR we didn't provide it at all (for dev purposes).
-                if tls.is_some() {
-                    stream.throw_error_str(ERR_INSECURE_CONNECTION).await?;
-                }
-
-                info!(session_type = "normal", "successful handshake");
-                break Ok(Some((stream, params)));
-            }
-            CancelRequest(cancel_key_data) => {
-                cancel_map
-                    .cancel_session(cancel_key_data)
-                    .await
-                    .map_err(HandshakeError::Cancel)?;
-
-                info!(session_type = "cancellation", "successful handshake");
-                break Ok(None);
-            }
-        }
-    }
-}
--- a/proxy/src/proxy/pass.rs
+++ b/proxy/src/proxy/pass.rs
@@ -1,82 +0,0 @@
-use crate::{
-    cancellation::Session,
-    console::messages::MetricsAuxInfo,
-    metrics::{NUM_BYTES_PROXIED_COUNTER, NUM_BYTES_PROXIED_PER_CLIENT_COUNTER},
-    state_machine::{DynStage, Finished, Stage, StageError},
-    stream::Stream,
-    usage_metrics::{Ids, USAGE_METRICS},
-};
-use tokio::io::{AsyncRead, AsyncWrite};
-use tracing::{error, info};
-use utils::measured_stream::MeasuredStream;
-
-pub struct ProxyPass<Client, Compute> {
-    pub client: Stream<Client>,
-    pub compute: Compute,
-
-    // monitoring
-    pub aux: MetricsAuxInfo,
-    pub cancel_session: Session,
-}
-
-impl<Client, Compute> Stage for ProxyPass<Client, Compute>
-where
-    Client: AsyncRead + AsyncWrite + Unpin + Send + 'static,
-    Compute: AsyncRead + AsyncWrite + Unpin + Send + 'static,
-{
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("proxy_pass")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        if let Err(e) = proxy_pass(self.client, self.compute, self.aux).await {
-            error!("{e:#}")
-        }
-
-        drop(self.cancel_session);
-
-        Ok(Box::new(Finished))
-    }
-}
-
-/// Forward bytes in both directions (client <-> compute).
-pub async fn proxy_pass(
-    client: impl AsyncRead + AsyncWrite + Unpin,
-    compute: impl AsyncRead + AsyncWrite + Unpin,
-    aux: MetricsAuxInfo,
-) -> anyhow::Result<()> {
-    let usage = USAGE_METRICS.register(Ids {
-        endpoint_id: aux.endpoint_id.clone(),
-        branch_id: aux.branch_id.clone(),
-    });
-
-    let m_sent = NUM_BYTES_PROXIED_COUNTER.with_label_values(&["tx"]);
-    let m_sent2 = NUM_BYTES_PROXIED_PER_CLIENT_COUNTER.with_label_values(&aux.traffic_labels("tx"));
-    let mut client = MeasuredStream::new(
-        client,
-        |_| {},
-        |cnt| {
-            // Number of bytes we sent to the client (outbound).
-            m_sent.inc_by(cnt as u64);
-            m_sent2.inc_by(cnt as u64);
-            usage.record_egress(cnt as u64);
-        },
-    );
-
-    let m_recv = NUM_BYTES_PROXIED_COUNTER.with_label_values(&["rx"]);
-    let m_recv2 = NUM_BYTES_PROXIED_PER_CLIENT_COUNTER.with_label_values(&aux.traffic_labels("rx"));
-    let mut compute = MeasuredStream::new(
-        compute,
-        |_| {},
-        |cnt| {
-            // Number of bytes the client sent to the compute node (inbound).
-            m_recv.inc_by(cnt as u64);
-            m_recv2.inc_by(cnt as u64);
-        },
-    );
-
-    // Starting from here we only proxy the client's traffic.
-    info!("performing the proxy pass...");
-    let _ = tokio::io::copy_bidirectional(&mut client, &mut compute).await?;
-
-    Ok(())
-}
--- a/proxy/src/proxy/tests.rs
+++ b/proxy/src/proxy/tests.rs
@@ -3,19 +3,14 @@
 mod mitm;

 use super::connect_compute::ConnectMechanism;
-use super::handshake::handshake;
 use super::retry::ShouldRetry;
 use super::*;
 use crate::auth::backend::{ComputeUserInfo, TestBackend};
 use crate::config::CertResolver;
 use crate::console::{self, CachedNodeInfo, NodeInfo};
-use crate::proxy::connect_compute::connect_to_compute;
 use crate::proxy::retry::{retry_after, NUM_RETRIES_CONNECT};
-use crate::stream::PqStream;
-use crate::{auth, compute, http, sasl, scram};
-use anyhow::bail;
+use crate::{auth, http, sasl, scram};
 use async_trait::async_trait;
-use pq_proto::BeMessage as Be;
 use rstest::rstest;
 use smol_str::SmolStr;
 use tokio_postgres::config::SslMode;
@@ -207,7 +202,7 @@ async fn handshake_tls_is_enforced_by_proxy() -> anyhow::Result<()> {
        .err() // -> Option<E>
        .context("server shouldn't accept client")?;

-    assert!(server_err.to_string().contains(ERR_INSECURE_CONNECTION));
+    assert!(client_err.to_string().contains(&server_err.to_string()));

    Ok(())
 }
--- a/proxy/src/proxy/tests/mitm.rs
+++ b/proxy/src/proxy/tests/mitm.rs
@@ -10,7 +10,7 @@ use super::*;
 use bytes::{Bytes, BytesMut};
 use futures::{SinkExt, StreamExt};
 use postgres_protocol::message::frontend;
-use tokio::io::{AsyncReadExt, AsyncWriteExt, DuplexStream};
+use tokio::io::{AsyncReadExt, DuplexStream};
 use tokio_postgres::config::SslMode;
 use tokio_postgres::tls::TlsConnect;
 use tokio_util::codec::{Decoder, Encoder};
--- a/proxy/src/proxy/wake_compute.rs
+++ b/proxy/src/proxy/wake_compute.rs
@@ -1,89 +0,0 @@
-use std::{borrow::Cow, ops::ControlFlow};
-
-use pq_proto::StartupMessageParams;
-use tokio::io::{AsyncRead, AsyncWrite};
-use tracing::{error, warn};
-
-use crate::{
-    auth::{
-        backend::{ComputeCredentialKeys, ComputeCredentials},
-        BackendType,
-    },
-    cancellation::Session,
-    console::{provider::ConsoleBackend, Api},
-    context::RequestMonitoring,
-    state_machine::{user_facing_error, DynStage, Stage, StageError},
-    stream::{PqStream, Stream},
-};
-
-use super::{
-    connect_compute::{handle_try_wake, NeedsComputeConnection, TcpMechanism},
-    retry::retry_after,
-};
-
-pub struct NeedsWakeCompute<S> {
-    pub stream: PqStream<Stream<S>>,
-    pub api: Cow<'static, ConsoleBackend>,
-    pub params: StartupMessageParams,
-    pub allow_self_signed_compute: bool,
-    pub creds: ComputeCredentials<ComputeCredentialKeys>,
-
-    // monitoring
-    pub ctx: RequestMonitoring,
-    pub cancel_session: Session,
-}
-
-impl<S: AsyncRead + AsyncWrite + Unpin + Send + 'static> Stage for NeedsWakeCompute<S> {
-    fn span(&self) -> tracing::Span {
-        tracing::info_span!("wake_compute")
-    }
-    async fn run(self) -> Result<DynStage, StageError> {
-        let Self {
-            stream,
-            api,
-            params,
-            allow_self_signed_compute,
-            creds,
-            mut ctx,
-            cancel_session,
-        } = self;
-
-        let mut num_retries = 0;
-        let mut node_info = loop {
-            let wake_res = api.wake_compute(&mut ctx, &creds.info).await;
-            match handle_try_wake(wake_res, num_retries) {
-                Err(e) => {
-                    error!(error = ?e, num_retries, retriable = false, "couldn't wake compute node");
-                    return Err(user_facing_error(e, &mut ctx, stream));
-                }
-                Ok(ControlFlow::Continue(e)) => {
-                    warn!(error = ?e, num_retries, retriable = true, "couldn't wake compute node");
-                }
-                Ok(ControlFlow::Break(n)) => break n,
-            }
-
-            let wait_duration = retry_after(num_retries);
-            num_retries += 1;
-            tokio::time::sleep(wait_duration).await;
-        };
-
-        ctx.set_project(node_info.aux.clone());
-
-        node_info.allow_self_signed_compute = allow_self_signed_compute;
-
-        match creds.keys {
-            #[cfg(feature = "testing")]
-            ComputeCredentialKeys::Password(password) => node_info.config.password(password),
-            ComputeCredentialKeys::AuthKeys(auth_keys) => node_info.config.auth_keys(auth_keys),
-        };
-
-        Ok(Box::new(NeedsComputeConnection {
-            stream,
-            user_info: BackendType::Console(api, creds.info),
-            mechanism: TcpMechanism { params },
-            node_info,
-            ctx,
-            cancel_session,
-        }))
-    }
-}
--- a/proxy/src/sasl.rs
+++ b/proxy/src/sasl.rs
@@ -10,7 +10,7 @@ mod channel_binding;
 mod messages;
 mod stream;

-use crate::error::{ReportableError, UserFacingError};
+use crate::error::UserFacingError;
 use std::io;
 use thiserror::Error;

@@ -37,25 +37,6 @@ pub enum Error {
    Io(#[from] io::Error),
 }

-impl ReportableError for Error {
-    fn get_error_type(&self) -> crate::error::ErrorKind {
-        match self {
-            Error::ChannelBindingFailed(_) => crate::error::ErrorKind::User,
-            Error::ChannelBindingBadMethod(_) => crate::error::ErrorKind::User,
-            Error::BadClientMessage(_) => crate::error::ErrorKind::User,
-            Error::MissingBinding => crate::error::ErrorKind::Service,
-            Error::Io(io) => match io.kind() {
-                // tokio postgres uses these for various scram failures
-                io::ErrorKind::InvalidInput
-                | io::ErrorKind::UnexpectedEof
-                | io::ErrorKind::Other => crate::error::ErrorKind::User,
-                // all other IO errors are likely disconnects.
-                _ => crate::error::ErrorKind::Disconnect,
-            },
-        }
-    }
-}
-
 impl UserFacingError for Error {
    fn to_string_client(&self) -> String {
        use Error::*;
--- a/proxy/src/serverless.rs
+++ b/proxy/src/serverless.rs
@@ -124,12 +124,6 @@ pub async fn task_main(
                            let cancel_map = Arc::new(CancelMap::default());
                            let session_id = uuid::Uuid::new_v4();

-                            let root_span = info_span!(
-                                "serverless",
-                                session = %session_id,
-                                %peer_addr,
-                            );
-
                            request_handler(
                                req,
                                config,
@@ -141,9 +135,12 @@ pub async fn task_main(
                                sni_name,
                                peer_addr.ip(),
                                endpoint_rate_limiter,
-                                root_span.clone(),
                            )
-                            .instrument(root_span)
+                            .instrument(info_span!(
+                                "serverless",
+                                session = %session_id,
+                                %peer_addr,
+                            ))
                            .await
                        }
                    },
@@ -208,7 +205,6 @@ async fn request_handler(
    sni_hostname: Option<String>,
    peer_addr: IpAddr,
    endpoint_rate_limiter: Arc<EndpointRateLimiter>,
-    root_span: tracing::Span,
 ) -> Result<Response<Body>, ApiError> {
    let host = request
        .headers()
@@ -219,33 +215,27 @@ async fn request_handler(

    // Check if the request is a websocket upgrade request.
    if hyper_tungstenite::is_upgrade_request(&request) {
-        info!("performing websocket upgrade");
+        info!(session_id = ?session_id, "performing websocket upgrade");

        let (response, websocket) = hyper_tungstenite::upgrade(&mut request, None)
            .map_err(|e| ApiError::BadRequest(e.into()))?;

        ws_connections.spawn(
            async move {
-                let ctx =
-                    RequestMonitoring::new(session_id, peer_addr, "ws", &config.region, root_span);
+                let mut ctx = RequestMonitoring::new(session_id, peer_addr, "ws", &config.region);

-                let websocket = match websocket.await {
-                    Err(e) => {
-                        error!("error in websocket connection: {e:#}");
-                        return;
-                    }
-                    Ok(ws) => ws,
-                };
-
-                websocket::serve_websocket(
+                if let Err(e) = websocket::serve_websocket(
                    config,
-                    ctx,
+                    &mut ctx,
                    websocket,
-                    cancel_map,
+                    &cancel_map,
                    host,
                    endpoint_rate_limiter,
                )
                .await
+                {
+                    error!(session_id = ?session_id, "error in websocket connection: {e:#}");
+                }
            }
            .in_current_span(),
        );
@@ -253,8 +243,7 @@ async fn request_handler(
        // Return the response so the spawned future can continue.
        Ok(response)
    } else if request.uri().path() == "/sql" && request.method() == Method::POST {
-        let mut ctx =
-            RequestMonitoring::new(session_id, peer_addr, "http", &config.region, root_span);
+        let mut ctx = RequestMonitoring::new(session_id, peer_addr, "http", &config.region);

        sql_over_http::handle(
            tls,
--- a/proxy/src/serverless/websocket.rs
+++ b/proxy/src/serverless/websocket.rs
@@ -9,7 +9,7 @@ use crate::{
 use bytes::{Buf, Bytes};
 use futures::{Sink, Stream};
 use hyper::upgrade::Upgraded;
-use hyper_tungstenite::{tungstenite::Message, WebSocketStream};
+use hyper_tungstenite::{tungstenite::Message, HyperWebsocket, WebSocketStream};
 use pin_project_lite::pin_project;

 use std::{
@@ -131,12 +131,13 @@ impl<S: AsyncRead + AsyncWrite + Unpin> AsyncBufRead for WebSocketRw<S> {

 pub async fn serve_websocket(
    config: &'static ProxyConfig,
-    ctx: RequestMonitoring,
-    websocket: WebSocketStream<Upgraded>,
-    cancel_map: Arc<CancelMap>,
+    ctx: &mut RequestMonitoring,
+    websocket: HyperWebsocket,
+    cancel_map: &CancelMap,
    hostname: Option<String>,
    endpoint_rate_limiter: Arc<EndpointRateLimiter>,
-) {
+) -> anyhow::Result<()> {
+    let websocket = websocket.await?;
    handle_client(
        config,
        ctx,
@@ -145,7 +146,8 @@ pub async fn serve_websocket(
        ClientMode::Websockets { hostname },
        endpoint_rate_limiter,
    )
-    .await
+    .await?;
+    Ok(())
 }

 #[cfg(test)]
--- a/proxy/src/state_machine.rs
+++ b/proxy/src/state_machine.rs
@@ -1,149 +0,0 @@
-use futures::Future;
-use pq_proto::{framed::Framed, BeMessage};
-use tokio::{io::AsyncWrite, task::JoinHandle};
-use tracing::{info, warn, Instrument};
-
-pub trait Captures<T> {}
-impl<T, U> Captures<T> for U {}
-
-#[must_use]
-pub enum StageError {
-    Flush(Framed<Box<dyn AsyncWrite + Unpin + Send + 'static>>),
-    Done,
-}
-
-impl StageError {
-    pub async fn finish(self) {
-        match self {
-            StageError::Flush(mut f) => {
-                // ignore result. we can't do anything about it.
-                // this is already the error case anyway...
-                if let Err(e) = f.flush().await {
-                    warn!("could not send message to user: {e:?}")
-                }
-            }
-            StageError::Done => {}
-        }
-        info!("task finished");
-    }
-}
-
-pub type DynStage = Box<dyn StageSpawn>;
-
-/// Stage represents a single stage in a state machine.
-pub trait Stage: 'static + Send {
-    /// The span this stage should be run inside.
-    fn span(&self) -> tracing::Span;
-    /// Run the current stage, returning a new [`DynStage`], or an error
-    ///
-    /// Can be implemented as `async fn run(self) -> Result<DynStage, StageError>`
-    fn run(self) -> impl 'static + Send + Future<Output = Result<DynStage, StageError>>;
-}
-
-pub enum StageResult {
-    Finished,
-    Run(JoinHandle<Result<DynStage, StageError>>),
-}
-
-pub trait StageSpawn: 'static + Send {
-    fn run(self: Box<Self>) -> StageResult;
-}
-
-/// Stage spawn is a helper trait for the state machine. It spawns the stages as a tokio task
-impl<S: Stage> StageSpawn for S {
-    fn run(self: Box<Self>) -> StageResult {
-        let span = self.span();
-        StageResult::Run(tokio::spawn(S::run(*self).instrument(span)))
-    }
-}
-
-pub struct Finished;
-
-impl StageSpawn for Finished {
-    fn run(self: Box<Self>) -> StageResult {
-        StageResult::Finished
-    }
-}
-
-use crate::{
-    context::RequestMonitoring,
-    error::{ErrorKind, UserFacingError},
-    stream::PqStream,
-};
-
-pub trait ResultExt<T, E> {
-    fn send_error_to_user<S>(
-        self,
-        ctx: &mut RequestMonitoring,
-        stream: PqStream<S>,
-    ) -> Result<(T, PqStream<S>), StageError>
-    where
-        S: AsyncWrite + Unpin + Send + 'static,
-        E: UserFacingError;
-
-    fn no_user_error(self, ctx: &mut RequestMonitoring, kind: ErrorKind) -> Result<T, StageError>
-    where
-        E: std::fmt::Display;
-}
-
-impl<T, E> ResultExt<T, E> for Result<T, E> {
-    fn send_error_to_user<S>(
-        self,
-        ctx: &mut RequestMonitoring,
-        stream: PqStream<S>,
-    ) -> Result<(T, PqStream<S>), StageError>
-    where
-        S: AsyncWrite + Unpin + Send + 'static,
-        E: UserFacingError,
-    {
-        match self {
-            Ok(t) => Ok((t, stream)),
-            Err(e) => Err(user_facing_error(e, ctx, stream)),
-        }
-    }
-
-    fn no_user_error(self, ctx: &mut RequestMonitoring, kind: ErrorKind) -> Result<T, StageError>
-    where
-        E: std::fmt::Display,
-    {
-        match self {
-            Ok(t) => Ok(t),
-            Err(e) => {
-                tracing::error!(
-                    kind = kind.to_str(),
-                    user_msg = "",
-                    "task finished with error: {e}"
-                );
-
-                ctx.error(kind);
-                ctx.log();
-                Err(StageError::Done)
-            }
-        }
-    }
-}
-
-pub fn user_facing_error<S, E>(
-    err: E,
-    ctx: &mut RequestMonitoring,
-    mut stream: PqStream<S>,
-) -> StageError
-where
-    S: AsyncWrite + Unpin + Send + 'static,
-    E: UserFacingError,
-{
-    let kind = err.get_error_type();
-    ctx.error(kind);
-    ctx.log();
-
-    let msg = err.to_string_client();
-    tracing::error!(
-        kind = kind.to_str(),
-        user_msg = msg,
-        "task finished with error: {err}"
-    );
-    if let Err(err) = stream.write_message_noflush(&BeMessage::ErrorResponse(&msg, None)) {
-        warn!("could not process error message: {err:?}")
-    }
-    StageError::Flush(stream.framed.map_stream_sync(|f| Box::new(f) as Box<_>))
-}
--- a/proxy/src/stream.rs
+++ b/proxy/src/stream.rs
@@ -1,5 +1,5 @@
 use crate::config::TlsServerEndPoint;
-use crate::error::ErrorKind;
+use crate::error::UserFacingError;
 use anyhow::bail;
 use bytes::BytesMut;

@@ -99,17 +99,24 @@ impl<S: AsyncWrite + Unpin> PqStream<S> {
    /// Allowing string literals is safe under the assumption they might not contain any runtime info.
    /// This method exists due to `&str` not implementing `Into<anyhow::Error>`.
    pub async fn throw_error_str<T>(&mut self, error: &'static str) -> anyhow::Result<T> {
-        let kind = ErrorKind::User;
-        tracing::error!(
-            kind = kind.to_str(),
-            full_msg = error,
-            user_msg = error,
-            "task finished with error"
-        );
+        tracing::info!("forwarding error to user: {error}");
        self.write_message(&BeMessage::ErrorResponse(error, None))
            .await?;
        bail!(error)
    }
+
+    /// Write the error message using [`Self::write_message`], then re-throw it.
+    /// Trait [`UserFacingError`] acts as an allowlist for error types.
+    pub async fn throw_error<T, E>(&mut self, error: E) -> anyhow::Result<T>
+    where
+        E: UserFacingError + Into<anyhow::Error>,
+    {
+        let msg = error.to_string_client();
+        tracing::info!("forwarding error to user: {msg}");
+        self.write_message(&BeMessage::ErrorResponse(&msg, None))
+            .await?;
+        bail!(error)
+    }
 }

 /// Wrapper for upgrading raw streams into secure streams.
--- a/safekeeper/src/bin/safekeeper.rs
+++ b/safekeeper/src/bin/safekeeper.rs
@@ -8,6 +8,8 @@ use futures::future::BoxFuture;
 use futures::stream::FuturesUnordered;
 use futures::{FutureExt, StreamExt};
 use remote_storage::RemoteStorageConfig;
+use safekeeper::control_file::FileStorage;
+use safekeeper::state::TimelinePersistentState;
 use sd_notify::NotifyState;
 use tokio::runtime::Handle;
 use tokio::signal::unix::{signal, SignalKind};
@@ -30,12 +32,12 @@ use safekeeper::defaults::{
    DEFAULT_HEARTBEAT_TIMEOUT, DEFAULT_HTTP_LISTEN_ADDR, DEFAULT_MAX_OFFLOADER_LAG_BYTES,
    DEFAULT_PG_LISTEN_ADDR,
 };
-use safekeeper::wal_service;
 use safekeeper::GlobalTimelines;
 use safekeeper::SafeKeeperConf;
 use safekeeper::{broker, WAL_SERVICE_RUNTIME};
 use safekeeper::{control_file, BROKER_RUNTIME};
 use safekeeper::{http, WAL_REMOVER_RUNTIME};
+use safekeeper::{json_merge, wal_service};
 use safekeeper::{remove_wal, WAL_BACKUP_RUNTIME};
 use safekeeper::{wal_backup, HTTP_RUNTIME};
 use storage_broker::DEFAULT_ENDPOINT;
@@ -105,9 +107,6 @@ struct Args {
    /// Do not wait for changes to be written safely to disk. Unsafe.
    #[arg(short, long)]
    no_sync: bool,
-    /// Dump control file at path specified by this argument and exit.
-    #[arg(long)]
-    dump_control_file: Option<Utf8PathBuf>,
    /// Broker endpoint for storage nodes coordination in the form
    /// http[s]://host:port. In case of https schema TLS is connection is
    /// established; plaintext otherwise.
@@ -166,6 +165,21 @@ struct Args {
    /// useful for debugging.
    #[arg(long)]
    current_thread_runtime: bool,
+    /// Dump control file at path specified by this argument and exit.
+    #[arg(long)]
+    dump_control_file: Option<Utf8PathBuf>,
+    /// Patch control file at path specified by this argument and exit.
+    /// Patch is specified in --patch option and imposed over
+    /// control file as per rfc7386.
+    /// Without --write-patched the result is only printed.
+    #[arg(long, verbatim_doc_comment)]
+    patch_control_file: Option<Utf8PathBuf>,
+    /// The patch to apply to control file at --patch-control-file, in JSON.
+    #[arg(long, default_value = None)]
+    patch: Option<String>,
+    /// Write --patch-control-file result back in place.
+    #[arg(long, default_value = "false")]
+    write_patched: bool,
 }

 // Like PathBufValueParser, but allows empty string.
@@ -207,7 +221,13 @@ async fn main() -> anyhow::Result<()> {
    if let Some(addr) = args.dump_control_file {
        let state = control_file::FileStorage::load_control_file(addr)?;
        let json = serde_json::to_string(&state)?;
-        print!("{json}");
+        println!("{json}");
+        return Ok(());
+    }
+
+    if let Some(cfile_path) = args.patch_control_file {
+        let patch = args.patch.ok_or(anyhow::anyhow!("patch is missing"))?;
+        patch_control_file(cfile_path, patch, args.write_patched).await?;
        return Ok(());
    }

@@ -529,6 +549,26 @@ fn parse_remote_storage(storage_conf: &str) -> anyhow::Result<RemoteStorageConfi
    })
 }

+async fn patch_control_file(
+    cfile_path: Utf8PathBuf,
+    patch: String,
+    write: bool,
+) -> anyhow::Result<()> {
+    let state = control_file::FileStorage::load_control_file(&cfile_path)?;
+    // serialize to json, impose patch and deserialize back
+    let mut state_json =
+        serde_json::to_value(state).context("failed to serialize state to json")?;
+    let patch_json = serde_json::from_str(&patch).context("failed to parse patch")?;
+    json_merge(&mut state_json, patch_json);
+    let patched_state: TimelinePersistentState =
+        serde_json::from_value(state_json.clone()).context("failed to deserialize patched json")?;
+    println!("{state_json}");
+    if write {
+        FileStorage::do_persist(&patched_state, &cfile_path, true).await?;
+    }
+    return Ok(());
+}
+
 #[test]
 fn verify_cli() {
    use clap::CommandFactory;
--- a/safekeeper/src/control_file.rs
+++ b/safekeeper/src/control_file.rs
@@ -2,7 +2,7 @@

 use anyhow::{bail, ensure, Context, Result};
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
-use camino::Utf8PathBuf;
+use camino::{Utf8Path, Utf8PathBuf};
 use tokio::fs::{self, File};
 use tokio::io::AsyncWriteExt;

@@ -155,6 +155,46 @@ impl FileStorage {
            })?;
        Ok(state)
    }
+
+    /// Persist state s to dst_path, optionally fsyncing file.
+    pub async fn do_persist(
+        s: &TimelinePersistentState,
+        dst_path: &Utf8Path,
+        sync: bool,
+    ) -> Result<()> {
+        let mut f = File::create(&dst_path)
+            .await
+            .with_context(|| format!("failed to create partial control file at: {}", &dst_path))?;
+        let mut buf: Vec<u8> = Vec::new();
+        WriteBytesExt::write_u32::<LittleEndian>(&mut buf, SK_MAGIC)?;
+        WriteBytesExt::write_u32::<LittleEndian>(&mut buf, SK_FORMAT_VERSION)?;
+        s.ser_into(&mut buf)?;
+
+        // calculate checksum before resize
+        let checksum = crc32c::crc32c(&buf);
+        buf.extend_from_slice(&checksum.to_le_bytes());
+
+        f.write_all(&buf).await.with_context(|| {
+            format!(
+                "failed to write safekeeper state into control file at: {}",
+                dst_path
+            )
+        })?;
+        f.flush().await.with_context(|| {
+            format!(
+                "failed to flush safekeeper state into control file at: {}",
+                dst_path
+            )
+        })?;
+
+        // fsync the file
+        if sync {
+            f.sync_all()
+                .await
+                .with_context(|| format!("failed to sync partial control file at {}", dst_path))?;
+        }
+        Ok(())
+    }
 }

 impl Deref for FileStorage {
@@ -167,7 +207,7 @@ impl Deref for FileStorage {

 #[async_trait::async_trait]
 impl Storage for FileStorage {
-    /// Persists state durably to the underlying storage.
+    /// Atomically persists state durably to the underlying storage.
    ///
    /// For a description, see <https://lwn.net/Articles/457667/>.
    async fn persist(&mut self, s: &TimelinePersistentState) -> Result<()> {
@@ -175,46 +215,9 @@ impl Storage for FileStorage {

        // write data to safekeeper.control.partial
        let control_partial_path = self.timeline_dir.join(CONTROL_FILE_NAME_PARTIAL);
-        let mut control_partial = File::create(&control_partial_path).await.with_context(|| {
-            format!(
-                "failed to create partial control file at: {}",
-                &control_partial_path
-            )
-        })?;
-        let mut buf: Vec<u8> = Vec::new();
-        WriteBytesExt::write_u32::<LittleEndian>(&mut buf, SK_MAGIC)?;
-        WriteBytesExt::write_u32::<LittleEndian>(&mut buf, SK_FORMAT_VERSION)?;
-        s.ser_into(&mut buf)?;
-
-        // calculate checksum before resize
-        let checksum = crc32c::crc32c(&buf);
-        buf.extend_from_slice(&checksum.to_le_bytes());
-
-        control_partial.write_all(&buf).await.with_context(|| {
-            format!(
-                "failed to write safekeeper state into control file at: {}",
-                control_partial_path
-            )
-        })?;
-        control_partial.flush().await.with_context(|| {
-            format!(
-                "failed to flush safekeeper state into control file at: {}",
-                control_partial_path
-            )
-        })?;
-
-        // fsync the file
-        if !self.conf.no_sync {
-            control_partial.sync_all().await.with_context(|| {
-                format!(
-                    "failed to sync partial control file at {}",
-                    control_partial_path
-                )
-            })?;
-        }
+        FileStorage::do_persist(s, &control_partial_path, !self.conf.no_sync).await?;

        let control_path = self.timeline_dir.join(CONTROL_FILE_NAME);
-
        // rename should be atomic
        fs::rename(&control_partial_path, &control_path).await?;
        // this sync is not required by any standard but postgres does this (see durable_rename)
--- a/safekeeper/src/lib.rs
+++ b/safekeeper/src/lib.rs
@@ -2,6 +2,7 @@
 use camino::Utf8PathBuf;
 use once_cell::sync::Lazy;
 use remote_storage::RemoteStorageConfig;
+use serde_json::Value;
 use tokio::runtime::Runtime;

 use std::time::Duration;
@@ -175,3 +176,24 @@ pub static METRICS_SHIFTER_RUNTIME: Lazy<Runtime> = Lazy::new(|| {
        .build()
        .expect("Failed to create broker runtime")
 });
+
+/// Merge json b into json a according to
+/// https://www.rfc-editor.org/rfc/rfc7396
+/// https://stackoverflow.com/a/54118457/4014587
+pub fn json_merge(a: &mut Value, b: Value) {
+    if let Value::Object(a) = a {
+        if let Value::Object(b) = b {
+            for (k, v) in b {
+                if v.is_null() {
+                    a.remove(&k);
+                } else {
+                    json_merge(a.entry(k).or_insert(Value::Null), v);
+                }
+            }
+
+            return;
+        }
+    }
+
+    *a = b;
+}
--- a/safekeeper/src/metrics.rs
+++ b/safekeeper/src/metrics.rs
@@ -110,7 +110,7 @@ pub static REMOVED_WAL_SEGMENTS: Lazy<IntCounter> = Lazy::new(|| {
 pub static BACKED_UP_SEGMENTS: Lazy<IntCounter> = Lazy::new(|| {
    register_int_counter!(
        "safekeeper_backed_up_segments_total",
-        "Number of WAL segments backed up to the S3"
+        "Number of WAL segments backed up to the broker"
    )
    .expect("Failed to register safekeeper_backed_up_segments_total counter")
 });
@@ -337,7 +337,6 @@ pub struct TimelineCollector {
    flushed_wal_seconds: GaugeVec,
    collect_timeline_metrics: Gauge,
    timelines_count: IntGauge,
-    active_timelines_count: IntGauge,
 }

 impl Default for TimelineCollector {
@@ -521,13 +520,6 @@ impl TimelineCollector {
        .unwrap();
        descs.extend(timelines_count.desc().into_iter().cloned());

-        let active_timelines_count = IntGauge::new(
-            "safekeeper_active_timelines",
-            "Total number of active timelines",
-        )
-        .unwrap();
-        descs.extend(active_timelines_count.desc().into_iter().cloned());
-
        TimelineCollector {
            descs,
            commit_lsn,
@@ -548,7 +540,6 @@ impl TimelineCollector {
            flushed_wal_seconds,
            collect_timeline_metrics,
            timelines_count,
-            active_timelines_count,
        }
    }
 }
@@ -581,7 +572,6 @@ impl Collector for TimelineCollector {

        let timelines = GlobalTimelines::get_all();
        let timelines_count = timelines.len();
-        let mut active_timelines_count = 0;

        // Prometheus Collector is sync, and data is stored under async lock. To
        // bridge the gap with a crutch, collect data in spawned thread with
@@ -600,10 +590,6 @@ impl Collector for TimelineCollector {
            let timeline_id = tli.ttid.timeline_id.to_string();
            let labels = &[tenant_id.as_str(), timeline_id.as_str()];

-            if tli.timeline_is_active {
-                active_timelines_count += 1;
-            }
-
            self.commit_lsn
                .with_label_values(labels)
                .set(tli.mem_state.commit_lsn.into());
@@ -695,8 +681,6 @@ impl Collector for TimelineCollector {

        // report total number of timelines
        self.timelines_count.set(timelines_count as i64);
-        self.active_timelines_count
-            .set(active_timelines_count as i64);
        mfs.extend(self.timelines_count.collect());

        mfs
--- a/safekeeper/src/remove_wal.rs
+++ b/safekeeper/src/remove_wal.rs
@@ -10,15 +10,11 @@ use crate::{GlobalTimelines, SafeKeeperConf};
 pub async fn task_main(conf: SafeKeeperConf) -> anyhow::Result<()> {
    let wal_removal_interval = Duration::from_millis(5000);
    loop {
-        let now = tokio::time::Instant::now();
-        let mut active_timelines = 0;
-
        let tlis = GlobalTimelines::get_all();
        for tli in &tlis {
            if !tli.is_active().await {
                continue;
            }
-            active_timelines += 1;
            let ttid = tli.ttid;
            async {
                if let Err(e) = tli.maybe_persist_control_file().await {
@@ -31,17 +27,6 @@ pub async fn task_main(conf: SafeKeeperConf) -> anyhow::Result<()> {
            .instrument(info_span!("WAL removal", ttid = %ttid))
            .await;
        }
-
-        let elapsed = now.elapsed();
-        let total_timelines = tlis.len();
-
-        if elapsed > wal_removal_interval {
-            info!(
-                "WAL removal is too long, processed {} active timelines ({} total) in {:?}",
-                active_timelines, total_timelines, elapsed
-            );
-        }
-
        sleep(wal_removal_interval).await;
    }
 }
--- a/test_runner/fixtures/neon_fixtures.py
+++ b/test_runner/fixtures/neon_fixtures.py
@@ -2914,7 +2914,6 @@ class Endpoint(PgProtocol):

        # Write it back updated
        with open(config_path, "w") as file:
-            log.info(json.dumps(dict(data_dict, **kwargs)))
            json.dump(dict(data_dict, **kwargs), file, indent=4)

    # Mock the extension part of spec passed from control plane for local testing
--- a/test_runner/regress/test_ddl_forwarding.py
+++ b/test_runner/regress/test_ddl_forwarding.py
@@ -248,15 +248,8 @@ def test_ddl_forwarding(ddl: DdlForwardingContext):
    # We don't have compute_ctl, so here, so create neon_superuser here manually
    cur.execute("CREATE ROLE neon_superuser NOLOGIN CREATEDB CREATEROLE")

-    # Contrary to popular belief, being superman does not make you superuser
-    cur.execute("CREATE ROLE superman LOGIN NOSUPERUSER PASSWORD 'jungle_man'")
-
-    with ddl.pg.cursor(user="superman", password="jungle_man") as superman_cur:
-        # We allow real SUPERUSERs to ALTER neon_superuser
-        with pytest.raises(psycopg2.InternalError):
-            superman_cur.execute("ALTER ROLE neon_superuser LOGIN")
-
-    cur.execute("ALTER ROLE neon_superuser LOGIN")
+    with pytest.raises(psycopg2.InternalError):
+        cur.execute("ALTER ROLE neon_superuser LOGIN")

    with pytest.raises(psycopg2.InternalError):
        cur.execute("CREATE DATABASE trololobus WITH OWNER neon_superuser")
--- a/test_runner/regress/test_migrations.py
+++ b/test_runner/regress/test_migrations.py
@@ -1,37 +0,0 @@
-import time
-
-from fixtures.neon_fixtures import NeonEnv
-
-
-def test_migrations(neon_simple_env: NeonEnv):
-    env = neon_simple_env
-    env.neon_cli.create_branch("test_migrations", "empty")
-
-    endpoint = env.endpoints.create("test_migrations")
-    log_path = endpoint.endpoint_path() / "compute.log"
-
-    endpoint.respec(skip_pg_catalog_updates=False, features=["migrations"])
-    endpoint.start()
-
-    time.sleep(1)  # Sleep to let migrations run
-
-    with endpoint.cursor() as cur:
-        cur.execute("SELECT id FROM neon_migration.migration_id")
-        migration_id = cur.fetchall()
-        assert migration_id[0][0] == 2
-
-    with open(log_path, "r") as log_file:
-        logs = log_file.read()
-        assert "INFO handle_migrations: Ran 2 migrations" in logs
-
-    endpoint.stop()
-    endpoint.start()
-    time.sleep(1)  # Sleep to let migrations run
-    with endpoint.cursor() as cur:
-        cur.execute("SELECT id FROM neon_migration.migration_id")
-        migration_id = cur.fetchall()
-        assert migration_id[0][0] == 2
-
-    with open(log_path, "r") as log_file:
-        logs = log_file.read()
-        assert "INFO handle_migrations: Ran 0 migrations" in logs
--- a/test_runner/regress/test_next_xid.py
+++ b/test_runner/regress/test_next_xid.py
@@ -1,18 +1,10 @@
-import json
-import os
 import time
-from pathlib import Path

-from fixtures.log_helper import log
-from fixtures.neon_fixtures import NeonEnvBuilder, wait_for_wal_insert_lsn
-from fixtures.pageserver.utils import (
-    wait_for_last_record_lsn,
-)
-from fixtures.remote_storage import RemoteStorageKind
-from fixtures.types import Lsn, TenantId, TimelineId
-from fixtures.utils import query_scalar
+from fixtures.neon_fixtures import NeonEnvBuilder


+# Test restarting page server, while safekeeper and compute node keep
+# running.
 def test_next_xid(neon_env_builder: NeonEnvBuilder):
    env = neon_env_builder.init_start()

@@ -60,161 +52,3 @@ def test_next_xid(neon_env_builder: NeonEnvBuilder):
    cur = conn.cursor()
    cur.execute("SELECT count(*) FROM t")
    assert cur.fetchone() == (iterations,)
-
-
-# Test for a bug we had, where nextXid was incorrectly updated when the
-# XID counter reached 2 billion. The nextXid tracking logic incorrectly
-# treated 0 (InvalidTransactionId) as a regular XID, and after reaching
-# 2 billion, it started to look like a very new XID, which caused nextXid
-# to be immediately advanced to the next epoch.
-#
-def test_import_at_2bil(
-    neon_env_builder: NeonEnvBuilder,
-    test_output_dir: Path,
-    pg_distrib_dir: Path,
-    pg_bin,
-    vanilla_pg,
-):
-    neon_env_builder.enable_pageserver_remote_storage(RemoteStorageKind.LOCAL_FS)
-    env = neon_env_builder.init_start()
-    ps_http = env.pageserver.http_client()
-
-    # Set LD_LIBRARY_PATH in the env properly, otherwise we may use the wrong libpq.
-    # PgBin sets it automatically, but here we need to pipe psql output to the tar command.
-    psql_env = {"LD_LIBRARY_PATH": str(pg_distrib_dir / "lib")}
-
-    # Reset the vanilla Postgres instance to somewhat before 2 billion transactions.
-    pg_resetwal_path = os.path.join(pg_bin.pg_bin_path, "pg_resetwal")
-    cmd = [pg_resetwal_path, "--next-transaction-id=2129920000", "-D", str(vanilla_pg.pgdatadir)]
-    pg_bin.run_capture(cmd, env=psql_env)
-
-    vanilla_pg.start()
-    vanilla_pg.safe_psql("create user cloud_admin with password 'postgres' superuser")
-    vanilla_pg.safe_psql(
-        """create table tt as select 'long string to consume some space' || g
-     from generate_series(1,300000) g"""
-    )
-    assert vanilla_pg.safe_psql("select count(*) from tt") == [(300000,)]
-    vanilla_pg.safe_psql("CREATE TABLE t (t text);")
-    vanilla_pg.safe_psql("INSERT INTO t VALUES ('inserted in vanilla')")
-
-    endpoint_id = "ep-import_from_vanilla"
-    tenant = TenantId.generate()
-    timeline = TimelineId.generate()
-
-    env.pageserver.tenant_create(tenant)
-
-    # Take basebackup
-    basebackup_dir = os.path.join(test_output_dir, "basebackup")
-    base_tar = os.path.join(basebackup_dir, "base.tar")
-    wal_tar = os.path.join(basebackup_dir, "pg_wal.tar")
-    os.mkdir(basebackup_dir)
-    vanilla_pg.safe_psql("CHECKPOINT")
-    pg_bin.run(
-        [
-            "pg_basebackup",
-            "-F",
-            "tar",
-            "-d",
-            vanilla_pg.connstr(),
-            "-D",
-            basebackup_dir,
-        ]
-    )
-
-    # Get start_lsn and end_lsn
-    with open(os.path.join(basebackup_dir, "backup_manifest")) as f:
-        manifest = json.load(f)
-        start_lsn = manifest["WAL-Ranges"][0]["Start-LSN"]
-        end_lsn = manifest["WAL-Ranges"][0]["End-LSN"]
-
-    def import_tar(base, wal):
-        env.neon_cli.raw_cli(
-            [
-                "timeline",
-                "import",
-                "--tenant-id",
-                str(tenant),
-                "--timeline-id",
-                str(timeline),
-                "--node-name",
-                endpoint_id,
-                "--base-lsn",
-                start_lsn,
-                "--base-tarfile",
-                base,
-                "--end-lsn",
-                end_lsn,
-                "--wal-tarfile",
-                wal,
-                "--pg-version",
-                env.pg_version,
-            ]
-        )
-
-    # Importing correct backup works
-    import_tar(base_tar, wal_tar)
-    wait_for_last_record_lsn(ps_http, tenant, timeline, Lsn(end_lsn))
-
-    endpoint = env.endpoints.create_start(
-        endpoint_id,
-        tenant_id=tenant,
-        config_lines=[
-            "log_autovacuum_min_duration = 0",
-            "autovacuum_naptime='5 s'",
-        ],
-    )
-    assert endpoint.safe_psql("select count(*) from t") == [(1,)]
-
-    # Ok, consume
-    conn = endpoint.connect()
-    cur = conn.cursor()
-
-    # Install extension containing function needed for test
-    cur.execute("CREATE EXTENSION neon_test_utils")
-
-    # Advance nextXid close to 2 billion XIDs
-    while True:
-        xid = int(query_scalar(cur, "SELECT txid_current()"))
-        log.info(f"xid now {xid}")
-        # Consume 10k transactons at a time until we get to 2^31 - 200k
-        if xid < 2 * 1024 * 1024 * 1024 - 100000:
-            cur.execute("select test_consume_xids(50000);")
-        elif xid < 2 * 1024 * 1024 * 1024 - 10000:
-            cur.execute("select test_consume_xids(5000);")
-        else:
-            break
-
-    # Run a bunch of real INSERTs to cross over the 2 billion mark
-    # Use a begin-exception block to have a separate sub-XID for each insert.
-    cur.execute(
-        """
-        do $$
-        begin
-          for i in 1..10000 loop
-            -- Use a begin-exception block to generate a new subtransaction on each iteration
-            begin
-              insert into t values (i);
-            exception when others then
-              raise 'not expected %', sqlerrm;
-            end;
-          end loop;
-        end;
-        $$;
-        """
-    )
-    # A checkpoint writes a WAL record with xl_xid=0. Many other WAL
-    # records would have the same effect.
-    cur.execute("checkpoint")
-
-    # wait until pageserver receives that data
-    wait_for_wal_insert_lsn(env, endpoint, tenant, timeline)
-
-    # Restart endpoint
-    endpoint.stop()
-    endpoint.start()
-
-    conn = endpoint.connect()
-    cur = conn.cursor()
-    cur.execute("SELECT count(*) from t")
-    assert cur.fetchone() == (10000 + 1,)
--- a/test_runner/regress/test_pageserver_reconnect.py
+++ b/test_runner/regress/test_pageserver_reconnect.py
@@ -1,42 +0,0 @@
-import threading
-import time
-from contextlib import closing
-
-from fixtures.log_helper import log
-from fixtures.neon_fixtures import NeonEnv, PgBin
-
-
-# Test updating neon.pageserver_connstring setting on the fly.
-#
-# This merely changes some whitespace in the connection string, so
-# this doesn't prove that the new string actually takes effect. But at
-# least the code gets exercised.
-def test_pageserver_reconnect(neon_simple_env: NeonEnv, pg_bin: PgBin):
-    env = neon_simple_env
-    env.neon_cli.create_branch("test_pageserver_restarts")
-    endpoint = env.endpoints.create_start("test_pageserver_restarts")
-    n_reconnects = 1000
-    timeout = 0.01
-    scale = 10
-
-    def run_pgbench(connstr: str):
-        log.info(f"Start a pgbench workload on pg {connstr}")
-        pg_bin.run_capture(["pgbench", "-i", f"-s{scale}", connstr])
-        pg_bin.run_capture(["pgbench", f"-T{int(n_reconnects*timeout)}", connstr])
-
-    thread = threading.Thread(target=run_pgbench, args=(endpoint.connstr(),), daemon=True)
-    thread.start()
-
-    with closing(endpoint.connect()) as con:
-        with con.cursor() as c:
-            c.execute("SELECT setting FROM pg_settings WHERE name='neon.pageserver_connstring'")
-            connstring = c.fetchall()[0][0]
-            for i in range(n_reconnects):
-                time.sleep(timeout)
-                c.execute(
-                    "alter system set neon.pageserver_connstring=%s",
-                    (connstring + (" " * (i % 2)),),
-                )
-                c.execute("select pg_reload_conf()")
-
-    thread.join()
--- a/test_runner/regress/test_vm_bits.py
+++ b/test_runner/regress/test_vm_bits.py
@@ -1,4 +1,3 @@
-import pytest
 from fixtures.log_helper import log
 from fixtures.neon_fixtures import NeonEnv, fork_at_current_lsn

@@ -118,8 +117,6 @@ def test_vm_bit_clear(neon_simple_env: NeonEnv):
 # Test that the ALL_FROZEN VM bit is cleared correctly at a HEAP_LOCK
 # record.
 #
-# FIXME: This test is broken
-@pytest.mark.skip("See https://github.com/neondatabase/neon/pull/6412#issuecomment-1902072541")
 def test_vm_bit_clear_on_heap_lock(neon_simple_env: NeonEnv):
    env = neon_simple_env

--- a/workspace_hack/Cargo.toml
+++ b/workspace_hack/Cargo.toml
@@ -29,8 +29,10 @@ chrono = { version = "0.4", default-features = false, features = ["clock", "serd
 clap = { version = "4", features = ["derive", "string"] }
 clap_builder = { version = "4", default-features = false, features = ["color", "help", "std", "string", "suggestions", "usage"] }
 crossbeam-utils = { version = "0.8" }
+dashmap = { version = "5", default-features = false, features = ["raw-api"] }
 either = { version = "1" }
 fail = { version = "0.5", default-features = false, features = ["failpoints"] }
+futures = { version = "0.3" }
 futures-channel = { version = "0.3", features = ["sink"] }
 futures-core = { version = "0.3" }
 futures-executor = { version = "0.3" }
@@ -72,7 +74,6 @@ tokio-rustls = { version = "0.24" }
 tokio-util = { version = "0.7", features = ["codec", "compat", "io", "rt"] }
 toml_datetime = { version = "0.6", default-features = false, features = ["serde"] }
 toml_edit = { version = "0.19", features = ["serde"] }
-tonic = { version = "0.9", features = ["tls-roots"] }
 tower = { version = "0.4", default-features = false, features = ["balance", "buffer", "limit", "log", "timeout", "util"] }
 tracing = { version = "0.1", features = ["log"] }
 tracing-core = { version = "0.1" }