back to published versions

custom jemalloc opts
bump
2026-01-25 06:10:37 +00:00 · 2024-04-22 10:28:29 +01:00 · 2024-04-22 10:26:49 +01:00 · 2024-04-22 06:55:43 +01:00 · 2024-04-22 06:48:03 +01:00
134 changed files with 3071 additions and 6672 deletions
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -477,8 +477,6 @@ jobs:
          BUILD_TAG: ${{ needs.tag.outputs.build-tag }}
          PAGESERVER_VIRTUAL_FILE_IO_ENGINE: tokio-epoll-uring
          PAGESERVER_GET_VECTORED_IMPL: vectored
-          PAGESERVER_GET_IMPL: vectored
-          PAGESERVER_VALIDATE_VEC_GET: true

      # Temporary disable this step until we figure out why it's so flaky
      # Ref https://github.com/neondatabase/neon/issues/4540
@@ -558,9 +556,6 @@ jobs:
          PERF_TEST_RESULT_CONNSTR: "${{ secrets.PERF_TEST_RESULT_CONNSTR }}"
          TEST_RESULT_CONNSTR: "${{ secrets.REGRESS_TEST_RESULT_CONNSTR_NEW }}"
          PAGESERVER_VIRTUAL_FILE_IO_ENGINE: tokio-epoll-uring
-          PAGESERVER_GET_VECTORED_IMPL: vectored
-          PAGESERVER_GET_IMPL: vectored
-          PAGESERVER_VALIDATE_VEC_GET: false
      # XXX: no coverage data handling here, since benchmarks are run on release builds,
      # while coverage is currently collected for the debug ones

--- a/Cargo.lock
+++ b/Cargo.lock
@@ -722,9 +722,9 @@ dependencies = [

 [[package]]
 name = "azure_core"
-version = "0.19.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70fd680c0d0424a518229b1150922f92653ba2ac933aa000abc8bf1ca08105f7"
+checksum = "a6218987c374650fdad0b476bfc675729762c28dfb35f58608a38a2b1ea337dd"
 dependencies = [
 "async-trait",
 "base64 0.21.1",
@@ -752,9 +752,9 @@ dependencies = [

 [[package]]
 name = "azure_identity"
-version = "0.19.0"
+version = "0.18.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a6d2060f5b2e1c664026ca4edd561306c473be887c1f7a81f10bf06f9b71c63f"
+checksum = "9e1eacc4f7fb2a73d57c39139d0fc3aed78435606055779ddaef4b43cdf919a8"
 dependencies = [
 "async-lock",
 "async-trait",
@@ -772,9 +772,9 @@ dependencies = [

 [[package]]
 name = "azure_storage"
-version = "0.19.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "15d3da73bfa09350e1bd6ae2a260806fcf90048c7e78cd2d8f88be60b19a7266"
+checksum = "ade8f2653e408de88b9eafec9f48c3c26b94026375e88adbd34523a7dd9795a1"
 dependencies = [
 "RustyXML",
 "async-lock",
@@ -791,9 +791,9 @@ dependencies = [

 [[package]]
 name = "azure_storage_blobs"
-version = "0.19.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "149c21834a4105d761e3dd33d91c2a3064acc05a3c978848ea8089102ae45c94"
+checksum = "025701c7cc5b523100f0f3b2b01723564ec5a86c03236521c06826337047e872"
 dependencies = [
 "RustyXML",
 "azure_core",
@@ -812,9 +812,9 @@ dependencies = [

 [[package]]
 name = "azure_svc_blobstorage"
-version = "0.19.0"
+version = "0.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "88c888b7bf522d5405218b8613bf0fae7ddaae6ef3bf4ad42ae005993c96ab8b"
+checksum = "76051e5bb67cea1055abe5e530a0878feac7e0ab4cbbcb4a6adc953a58993389"
 dependencies = [
 "azure_core",
 "bytes",
@@ -2763,9 +2763,9 @@ dependencies = [

 [[package]]
 name = "js-sys"
-version = "0.3.69"
+version = "0.3.63"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29c15563dc2726973df627357ce0c9ddddbea194836909d655df6a75d2cf296d"
+checksum = "2f37a4a5928311ac501dee68b3c7613a1037d0edb30c8e5427bd832d55d1b790"
 dependencies = [
 "wasm-bindgen",
 ]
@@ -3658,7 +3658,6 @@ dependencies = [
 "tokio-util",
 "toml_edit",
 "tracing",
- "twox-hash",
 "url",
 "utils",
 "walkdir",
@@ -5085,7 +5084,6 @@ dependencies = [
 "aws-smithy-async",
 "bincode",
 "bytes",
- "camino",
 "chrono",
 "clap",
 "crc32c",
@@ -5832,7 +5830,8 @@ checksum = "81cdd64d312baedb58e21336b31bc043b77e01cc99033ce76ef539f78e965ebc"
 [[package]]
 name = "svg_fmt"
 version = "0.4.2"
-source = "git+https://github.com/neondatabase/fork--nical--rust_debug?branch=neon#b9501105e746629004bc6d0473639320939dbe10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f83ba502a3265efb76efb89b0a2f7782ad6f2675015d4ce37e4b547dda42b499"

 [[package]]
 name = "syn"
@@ -6413,10 +6412,11 @@ dependencies = [

 [[package]]
 name = "tracing"
-version = "0.1.40"
+version = "0.1.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3523ab5a71916ccf420eebdf5521fcef02141234bbc0b8a49f2fdc4544364ef"
+checksum = "8ce8c33a8d48bd45d624a6e523445fd21ec13d3653cd51f681abf67418f54eb8"
 dependencies = [
+ "cfg-if",
 "log",
 "pin-project-lite",
 "tracing-attributes",
@@ -6436,9 +6436,9 @@ dependencies = [

 [[package]]
 name = "tracing-attributes"
-version = "0.1.27"
+version = "0.1.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
+checksum = "0f57e3ca2a01450b1a921183a9c9cbfda207fd822cef4ccb00a65402cbba7a74"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -6447,9 +6447,9 @@ dependencies = [

 [[package]]
 name = "tracing-core"
-version = "0.1.32"
+version = "0.1.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c06d3da6113f116aaee68e4d601191614c9053067f9ab7f6edbcb161237daa54"
+checksum = "0955b8137a1df6f1a2e9a37d8a6656291ff0297c1a97c24e0d8425fe2312f79a"
 dependencies = [
 "once_cell",
 "valuable",
@@ -6904,9 +6904,9 @@ checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"

 [[package]]
 name = "wasm-bindgen"
-version = "0.2.92"
+version = "0.2.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4be2531df63900aeb2bca0daaaddec08491ee64ceecbee5076636a3b026795a8"
+checksum = "5bba0e8cb82ba49ff4e229459ff22a191bbe9a1cb3a341610c9c33efc27ddf73"
 dependencies = [
 "cfg-if",
 "wasm-bindgen-macro",
@@ -6914,9 +6914,9 @@ dependencies = [

 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.92"
+version = "0.2.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "614d787b966d3989fa7bb98a654e369c762374fd3213d212cfc0251257e747da"
+checksum = "19b04bc93f9d6bdee709f6bd2118f57dd6679cf1176a1af464fca3ab0d66d8fb"
 dependencies = [
 "bumpalo",
 "log",
@@ -6929,9 +6929,9 @@ dependencies = [

 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.42"
+version = "0.4.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "76bc14366121efc8dbb487ab05bcc9d346b3b5ec0eaa76e46594cabbe51762c0"
+checksum = "2d1985d03709c53167ce907ff394f5316aa22cb4e12761295c5dc57dacb6297e"
 dependencies = [
 "cfg-if",
 "js-sys",
@@ -6941,9 +6941,9 @@ dependencies = [

 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.92"
+version = "0.2.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1f8823de937b71b9460c0c34e25f3da88250760bec0ebac694b49997550d726"
+checksum = "14d6b024f1a526bb0234f52840389927257beb670610081360e5a03c5df9c258"
 dependencies = [
 "quote",
 "wasm-bindgen-macro-support",
@@ -6951,9 +6951,9 @@ dependencies = [

 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.92"
+version = "0.2.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e94f17b526d0a461a191c78ea52bbce64071ed5c04c9ffe424dcb38f74171bb7"
+checksum = "e128beba882dd1eb6200e1dc92ae6c5dbaa4311aa7bb211ca035779e5efc39f8"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -6964,9 +6964,9 @@ dependencies = [

 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.92"
+version = "0.2.86"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af190c94f2773fdb3729c55b007a722abb5384da03bc0986df4c289bf5567e96"
+checksum = "ed9d5b4305409d1fc9482fee2d7f9bcbf24b3972bf59817ef757e23982242a93"

 [[package]]
 name = "wasm-streams"
@@ -6998,9 +6998,9 @@ dependencies = [

 [[package]]
 name = "web-sys"
-version = "0.3.69"
+version = "0.3.63"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77afa9a11836342370f4817622a2f0f418b134426d91a82dfb48f532d2ec13ef"
+checksum = "3bdd9ef4e984da1187bf8110c5cf5b845fbc87a23602cdf912386a76fcd3a7c2"
 dependencies = [
 "js-sys",
 "wasm-bindgen",
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -45,10 +45,10 @@ anyhow = { version = "1.0", features = ["backtrace"] }
 arc-swap = "1.6"
 async-compression = { version = "0.4.0", features = ["tokio", "gzip", "zstd"] }
 atomic-take = "1.1.0"
-azure_core = "0.19"
-azure_identity = "0.19"
-azure_storage = "0.19"
-azure_storage_blobs = "0.19"
+azure_core = "0.18"
+azure_identity = "0.18"
+azure_storage = "0.18"
+azure_storage_blobs = "0.18"
 flate2 = "1.0.26"
 async-stream = "0.3"
 async-trait = "0.1"
@@ -157,8 +157,7 @@ socket2 = "0.5"
 strum = "0.24"
 strum_macros = "0.24"
 "subtle"  = "2.5.0"
-# https://github.com/nical/rust_debug/pull/4
-svg_fmt = { git = "https://github.com/neondatabase/fork--nical--rust_debug", branch = "neon" }
+svg_fmt = "0.4.1"
 sync_wrapper = "0.1.2"
 tar = "0.4"
 task-local-extensions = "0.1.4"
@@ -253,7 +252,7 @@ debug = true

 # disable debug symbols for all packages except this one to decrease binaries size
 [profile.release.package."*"]
-debug = false
+debug = true

 [profile.release-line-debug]
 inherits = "release"
--- a/1
+++ b/1
@@ -44,6 +44,7 @@ COPY --from=pg-build /home/nonroot/pg_install/v15/include/postgresql/server pg_i
 COPY --from=pg-build /home/nonroot/pg_install/v16/include/postgresql/server pg_install/v16/include/postgresql/server
 COPY --chown=nonroot . .

+ENV _RJEM_MALLOC_CONF="prof:true"
 # Show build caching stats to check if it was used in the end.
 # Has to be the part of the same RUN since cachepot daemon is killed in the end of this RUN, losing the compilation stats.
 RUN set -e \
--- a/control_plane/src/bin/neon_local.rs
+++ b/control_plane/src/bin/neon_local.rs
@@ -417,54 +417,6 @@ async fn handle_tenant(
                println!("{} {:?}", t.id, t.state);
            }
        }
-        Some(("import", import_match)) => {
-            let tenant_id = parse_tenant_id(import_match)?.unwrap_or_else(TenantId::generate);
-
-            let storage_controller = StorageController::from_env(env);
-            let create_response = storage_controller.tenant_import(tenant_id).await?;
-
-            let shard_zero = create_response
-                .shards
-                .first()
-                .expect("Import response omitted shards");
-
-            let attached_pageserver_id = shard_zero.node_id;
-            let pageserver =
-                PageServerNode::from_env(env, env.get_pageserver_conf(attached_pageserver_id)?);
-
-            println!(
-                "Imported tenant {tenant_id}, attached to pageserver {attached_pageserver_id}"
-            );
-
-            let timelines = pageserver
-                .http_client
-                .list_timelines(shard_zero.shard_id)
-                .await?;
-
-            // Pick a 'main' timeline that has no ancestors, the rest will get arbitrary names
-            let main_timeline = timelines
-                .iter()
-                .find(|t| t.ancestor_timeline_id.is_none())
-                .expect("No timelines found")
-                .timeline_id;
-
-            let mut branch_i = 0;
-            for timeline in timelines.iter() {
-                let branch_name = if timeline.timeline_id == main_timeline {
-                    "main".to_string()
-                } else {
-                    branch_i += 1;
-                    format!("branch_{branch_i}")
-                };
-
-                println!(
-                    "Importing timeline {tenant_id}/{} as branch {branch_name}",
-                    timeline.timeline_id
-                );
-
-                env.register_branch_mapping(branch_name, tenant_id, timeline.timeline_id)?;
-            }
-        }
        Some(("create", create_match)) => {
            let tenant_conf: HashMap<_, _> = create_match
                .get_many::<String>("config")
@@ -1528,8 +1480,6 @@ fn cli() -> Command {
            .subcommand(Command::new("config")
                .arg(tenant_id_arg.clone())
                .arg(Arg::new("config").short('c').num_args(1).action(ArgAction::Append).required(false)))
-            .subcommand(Command::new("import").arg(tenant_id_arg.clone().required(true))
-                .about("Import a tenant that is present in remote storage, and create branches for its timelines"))
        )
        .subcommand(
            Command::new("pageserver")
--- a/control_plane/src/local_env.rs
+++ b/control_plane/src/local_env.rs
@@ -129,8 +129,6 @@ pub struct PageServerConf {

    pub(crate) virtual_file_io_engine: Option<String>,
    pub(crate) get_vectored_impl: Option<String>,
-    pub(crate) get_impl: Option<String>,
-    pub(crate) validate_vectored_get: Option<bool>,
 }

 impl Default for PageServerConf {
@@ -143,8 +141,6 @@ impl Default for PageServerConf {
            http_auth_type: AuthType::Trust,
            virtual_file_io_engine: None,
            get_vectored_impl: None,
-            get_impl: None,
-            validate_vectored_get: None,
        }
    }
 }
--- a/control_plane/src/pageserver.rs
+++ b/control_plane/src/pageserver.rs
@@ -92,8 +92,6 @@ impl PageServerNode {
            http_auth_type,
            virtual_file_io_engine,
            get_vectored_impl,
-            get_impl,
-            validate_vectored_get,
        } = &self.conf;

        let id = format!("id={}", id);
@@ -113,16 +111,6 @@ impl PageServerNode {
        } else {
            String::new()
        };
-        let get_impl = if let Some(get_impl) = get_impl {
-            format!("get_impl='{get_impl}'")
-        } else {
-            String::new()
-        };
-        let validate_vectored_get = if let Some(validate_vectored_get) = validate_vectored_get {
-            format!("validate_vectored_get={validate_vectored_get}")
-        } else {
-            String::new()
-        };

        let broker_endpoint_param = format!("broker_endpoint='{}'", self.env.broker.client_url());

@@ -136,8 +124,6 @@ impl PageServerNode {
            broker_endpoint_param,
            virtual_file_io_engine,
            get_vectored_impl,
-            get_impl,
-            validate_vectored_get,
        ];

        if let Some(control_plane_api) = &self.env.control_plane_api {
@@ -448,11 +434,6 @@ impl PageServerNode {
                .map(serde_json::from_str)
                .transpose()
                .context("parse `timeline_get_throttle` from json")?,
-            switch_to_aux_file_v2: settings
-                .remove("switch_to_aux_file_v2")
-                .map(|x| x.parse::<bool>())
-                .transpose()
-                .context("Failed to parse 'switch_to_aux_file_v2' as bool")?,
        };
        if !settings.is_empty() {
            bail!("Unrecognized tenant settings: {settings:?}")
@@ -571,11 +552,6 @@ impl PageServerNode {
                    .map(serde_json::from_str)
                    .transpose()
                    .context("parse `timeline_get_throttle` from json")?,
-                switch_to_aux_file_v2: settings
-                    .remove("switch_to_aux_file_v2")
-                    .map(|x| x.parse::<bool>())
-                    .transpose()
-                    .context("Failed to parse 'switch_to_aux_file_v2' as bool")?,
            }
        };

--- a/control_plane/src/storage_controller.rs
+++ b/control_plane/src/storage_controller.rs
@@ -472,16 +472,6 @@ impl StorageController {
            .await
    }

-    #[instrument(skip(self))]
-    pub async fn tenant_import(&self, tenant_id: TenantId) -> anyhow::Result<TenantCreateResponse> {
-        self.dispatch::<(), TenantCreateResponse>(
-            Method::POST,
-            format!("debug/v1/tenant/{tenant_id}/import"),
-            None,
-        )
-        .await
-    }
-
    #[instrument(skip(self))]
    pub async fn tenant_locate(&self, tenant_id: TenantId) -> anyhow::Result<TenantLocateResponse> {
        self.dispatch::<(), _>(
--- a/libs/metrics/src/lib.rs
+++ b/libs/metrics/src/lib.rs
@@ -256,16 +256,7 @@ fn update_rusage_metrics() {
    DISK_IO_BYTES
        .with_label_values(&["write"])
        .set(rusage_stats.ru_oublock * BYTES_IN_BLOCK);
-
-    // On macOS, the unit of maxrss is bytes; on Linux, it's kilobytes. https://stackoverflow.com/a/59915669
-    #[cfg(target_os = "macos")]
-    {
-        MAXRSS_KB.set(rusage_stats.ru_maxrss / 1024);
-    }
-    #[cfg(not(target_os = "macos"))]
-    {
-        MAXRSS_KB.set(rusage_stats.ru_maxrss);
-    }
+    MAXRSS_KB.set(rusage_stats.ru_maxrss);
 }

 fn get_rusage_stats() -> libc::rusage {
--- a/libs/pageserver_api/src/key.rs
+++ b/libs/pageserver_api/src/key.rs
@@ -1,6 +1,5 @@
 use anyhow::{bail, Result};
 use byteorder::{ByteOrder, BE};
-use bytes::BufMut;
 use postgres_ffi::relfile_utils::{FSM_FORKNUM, VISIBILITYMAP_FORKNUM};
 use postgres_ffi::{Oid, TransactionId};
 use serde::{Deserialize, Serialize};
@@ -22,107 +21,15 @@ pub struct Key {
    pub field6: u32,
 }

-/// The storage key size.
 pub const KEY_SIZE: usize = 18;

-/// The metadata key size. 2B fewer than the storage key size because field2 is not fully utilized.
-/// See [`Key::to_i128`] for more information on the encoding.
-pub const METADATA_KEY_SIZE: usize = 16;
-
-/// The key prefix start range for the metadata keys. All keys with the first byte >= 0x40 is a metadata key.
-pub const METADATA_KEY_BEGIN_PREFIX: u8 = 0x60;
-pub const METADATA_KEY_END_PREFIX: u8 = 0x7F;
-
-/// The (reserved) key prefix of relation sizes.
-pub const RELATION_SIZE_PREFIX: u8 = 0x61;
-
-/// The key prefix of AUX file keys.
-pub const AUX_KEY_PREFIX: u8 = 0x62;
-
-/// Check if the key falls in the range of metadata keys.
-pub const fn is_metadata_key_slice(key: &[u8]) -> bool {
-    key[0] >= METADATA_KEY_BEGIN_PREFIX && key[0] < METADATA_KEY_END_PREFIX
-}
-
 impl Key {
-    /// Check if the key falls in the range of metadata keys.
-    pub const fn is_metadata_key(&self) -> bool {
-        self.field1 >= METADATA_KEY_BEGIN_PREFIX && self.field1 < METADATA_KEY_END_PREFIX
-    }
-
-    /// Encode a metadata key to a storage key.
-    pub fn from_metadata_key_fixed_size(key: &[u8; METADATA_KEY_SIZE]) -> Self {
-        assert!(is_metadata_key_slice(key), "key not in metadata key range");
-        Key {
-            field1: key[0],
-            field2: u16::from_be_bytes(key[1..3].try_into().unwrap()) as u32,
-            field3: u32::from_be_bytes(key[3..7].try_into().unwrap()),
-            field4: u32::from_be_bytes(key[7..11].try_into().unwrap()),
-            field5: key[11],
-            field6: u32::from_be_bytes(key[12..16].try_into().unwrap()),
-        }
-    }
-
-    /// Encode a metadata key to a storage key.
-    pub fn from_metadata_key(key: &[u8]) -> Self {
-        Self::from_metadata_key_fixed_size(key.try_into().expect("expect 16 byte metadata key"))
-    }
-
-    /// Extract a metadata key to a writer. The result should always be 16 bytes.
-    pub fn extract_metadata_key_to_writer(&self, mut writer: impl BufMut) {
-        writer.put_u8(self.field1);
-        assert!(self.field2 <= 0xFFFF);
-        writer.put_u16(self.field2 as u16);
-        writer.put_u32(self.field3);
-        writer.put_u32(self.field4);
-        writer.put_u8(self.field5);
-        writer.put_u32(self.field6);
-    }
-
-    /// Get the range of metadata keys.
-    pub fn metadata_key_range() -> Range<Self> {
-        Key {
-            field1: METADATA_KEY_BEGIN_PREFIX,
-            field2: 0,
-            field3: 0,
-            field4: 0,
-            field5: 0,
-            field6: 0,
-        }..Key {
-            field1: METADATA_KEY_END_PREFIX,
-            field2: 0,
-            field3: 0,
-            field4: 0,
-            field5: 0,
-            field6: 0,
-        }
-    }
-
-    /// Get the range of aux keys.
-    pub fn metadata_aux_key_range() -> Range<Self> {
-        Key {
-            field1: AUX_KEY_PREFIX,
-            field2: 0,
-            field3: 0,
-            field4: 0,
-            field5: 0,
-            field6: 0,
-        }..Key {
-            field1: AUX_KEY_PREFIX + 1,
-            field2: 0,
-            field3: 0,
-            field4: 0,
-            field5: 0,
-            field6: 0,
-        }
-    }
-
    /// 'field2' is used to store tablespaceid for relations and small enum numbers for other relish.
    /// As long as Neon does not support tablespace (because of lack of access to local file system),
    /// we can assume that only some predefined namespace OIDs are used which can fit in u16
    pub fn to_i128(&self) -> i128 {
        assert!(self.field2 < 0xFFFF || self.field2 == 0xFFFFFFFF || self.field2 == 0x22222222);
-        (((self.field1 & 0x7F) as i128) << 120)
+        (((self.field1 & 0xf) as i128) << 120)
            | (((self.field2 & 0xFFFF) as i128) << 104)
            | ((self.field3 as i128) << 72)
            | ((self.field4 as i128) << 40)
@@ -132,7 +39,7 @@ impl Key {

    pub const fn from_i128(x: i128) -> Self {
        Key {
-            field1: ((x >> 120) & 0x7F) as u8,
+            field1: ((x >> 120) & 0xf) as u8,
            field2: ((x >> 104) & 0xFFFF) as u32,
            field3: (x >> 72) as u32,
            field4: (x >> 40) as u32,
@@ -141,11 +48,11 @@ impl Key {
        }
    }

-    pub const fn next(&self) -> Key {
+    pub fn next(&self) -> Key {
        self.add(1)
    }

-    pub const fn add(&self, x: u32) -> Key {
+    pub fn add(&self, x: u32) -> Key {
        let mut key = *self;

        let r = key.field6.overflowing_add(x);
@@ -174,8 +81,6 @@ impl Key {
        key
    }

-    /// Convert a 18B slice to a key. This function should not be used for metadata keys because field2 is handled differently.
-    /// Use [`Key::from_metadata_key`] instead.
    pub fn from_slice(b: &[u8]) -> Self {
        Key {
            field1: b[0],
@@ -187,8 +92,6 @@ impl Key {
        }
    }

-    /// Convert a key to a 18B slice. This function should not be used for metadata keys because field2 is handled differently.
-    /// Use [`Key::extract_metadata_key_to_writer`] instead.
    pub fn write_to_byte_slice(&self, buf: &mut [u8]) {
        buf[0] = self.field1;
        BE::write_u32(&mut buf[1..5], self.field2);
@@ -572,14 +475,12 @@ pub const AUX_FILES_KEY: Key = Key {
 // Reverse mappings for a few Keys.
 // These are needed by WAL redo manager.

-pub const NON_INHERITED_RANGE: Range<Key> = AUX_FILES_KEY..AUX_FILES_KEY.next();
-
 // 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 {
-    !NON_INHERITED_RANGE.contains(&key)
+    key != AUX_FILES_KEY
 }

 #[inline(always)]
@@ -655,14 +556,11 @@ impl std::str::FromStr for Key {
 mod tests {
    use std::str::FromStr;

-    use crate::key::is_metadata_key_slice;
    use crate::key::Key;

    use rand::Rng;
    use rand::SeedableRng;

-    use super::AUX_KEY_PREFIX;
-
    #[test]
    fn display_fromstr_bijection() {
        let mut rng = rand::rngs::StdRng::seed_from_u64(42);
@@ -678,16 +576,4 @@ mod tests {

        assert_eq!(key, Key::from_str(&format!("{key}")).unwrap());
    }
-
-    #[test]
-    fn test_metadata_keys() {
-        let mut metadata_key = vec![AUX_KEY_PREFIX];
-        metadata_key.extend_from_slice(&[0xFF; 15]);
-        let encoded_key = Key::from_metadata_key(&metadata_key);
-        let mut output_key = Vec::new();
-        encoded_key.extract_metadata_key_to_writer(&mut output_key);
-        assert_eq!(metadata_key, output_key);
-        assert!(encoded_key.is_metadata_key());
-        assert!(is_metadata_key_slice(&metadata_key));
-    }
 }
--- a/libs/pageserver_api/src/keyspace.rs
+++ b/libs/pageserver_api/src/keyspace.rs
@@ -1,10 +1,7 @@
 use postgres_ffi::BLCKSZ;
 use std::ops::Range;

-use crate::{
-    key::Key,
-    shard::{ShardCount, ShardIdentity},
-};
+use crate::key::Key;
 use itertools::Itertools;

 ///
@@ -17,275 +14,44 @@ pub struct KeySpace {
    pub ranges: Vec<Range<Key>>,
 }

-/// Represents a contiguous half-open range of the keyspace, masked according to a particular
-/// ShardNumber's stripes: within this range of keys, only some "belong" to the current
-/// shard.
-///
-/// When we iterate over keys within this object, we will skip any keys that don't belong
-/// to this shard.
-///
-/// The start + end keys may not belong to the shard: these specify where layer files should
-/// start  + end, but we will never actually read/write those keys.
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub struct ShardedRange<'a> {
-    pub shard_identity: &'a ShardIdentity,
-    pub range: Range<Key>,
-}
-
-// Calculate the size of a range within the blocks of the same relation, or spanning only the
-// top page in the previous relation's space.
-fn contiguous_range_len(range: &Range<Key>) -> u32 {
-    debug_assert!(is_contiguous_range(range));
-    if range.start.field6 == 0xffffffff {
-        range.end.field6 + 1
-    } else {
-        range.end.field6 - range.start.field6
-    }
-}
-
-/// Return true if this key range includes only keys in the same relation's data blocks, or
-/// just spanning one relation and the logical size (0xffffffff) block of the relation before it.
-///
-/// Contiguous in this context means we know the keys are in use _somewhere_, but it might not
-/// be on our shard.  Later in ShardedRange we do the extra work to figure out how much
-/// of a given contiguous range is present on one shard.
-///
-/// This matters, because:
-/// - Within such ranges, keys are used contiguously.  Outside such ranges it is sparse.
-/// - Within such ranges, we may calculate distances using simple subtraction of field6.
-fn is_contiguous_range(range: &Range<Key>) -> bool {
-    range.start.field1 == range.end.field1
-        && range.start.field2 == range.end.field2
-        && range.start.field3 == range.end.field3
-        && range.start.field4 == range.end.field4
-        && (range.start.field5 == range.end.field5
-            || (range.start.field6 == 0xffffffff && range.start.field5 + 1 == range.end.field5))
-}
-
-impl<'a> ShardedRange<'a> {
-    pub fn new(range: Range<Key>, shard_identity: &'a ShardIdentity) -> Self {
-        Self {
-            shard_identity,
-            range,
-        }
-    }
-
-    /// Break up this range into chunks, each of which has at least one local key in it if the
-    /// total range has at least one local key.
-    pub fn fragment(self, target_nblocks: u32) -> Vec<(u32, Range<Key>)> {
-        // Optimization for single-key case (e.g. logical size keys)
-        if self.range.end == self.range.start.add(1) {
-            return vec![(
-                if self.shard_identity.is_key_disposable(&self.range.start) {
-                    0
-                } else {
-                    1
-                },
-                self.range,
-            )];
-        }
-
-        if !is_contiguous_range(&self.range) {
-            // Ranges that span relations are not fragmented.  We only get these ranges as a result
-            // of operations that act on existing layers, so we trust that the existing range is
-            // reasonably small.
-            return vec![(u32::MAX, self.range)];
-        }
-
-        let mut fragments: Vec<(u32, Range<Key>)> = Vec::new();
-
-        let mut cursor = self.range.start;
-        while cursor < self.range.end {
-            let advance_by = self.distance_to_next_boundary(cursor);
-            let is_fragment_disposable = self.shard_identity.is_key_disposable(&cursor);
-
-            // If the previous fragment is undersized, then we seek to consume enough
-            // blocks to complete it.
-            let (want_blocks, merge_last_fragment) = match fragments.last_mut() {
-                Some(frag) if frag.0 < target_nblocks => (target_nblocks - frag.0, Some(frag)),
-                Some(frag) => {
-                    // Prev block is complete, want the full number.
-                    (
-                        target_nblocks,
-                        if is_fragment_disposable {
-                            // If this current range will be empty (not shard-local data), we will merge into previous
-                            Some(frag)
-                        } else {
-                            None
-                        },
-                    )
-                }
-                None => {
-                    // First iteration, want the full number
-                    (target_nblocks, None)
-                }
-            };
-
-            let advance_by = if is_fragment_disposable {
-                advance_by
-            } else {
-                std::cmp::min(advance_by, want_blocks)
-            };
-
-            let next_cursor = cursor.add(advance_by);
-
-            let this_frag = (
-                if is_fragment_disposable {
-                    0
-                } else {
-                    advance_by
-                },
-                cursor..next_cursor,
-            );
-            cursor = next_cursor;
-
-            if let Some(last_fragment) = merge_last_fragment {
-                // Previous fragment was short or this one is empty, merge into it
-                last_fragment.0 += this_frag.0;
-                last_fragment.1.end = this_frag.1.end;
-            } else {
-                fragments.push(this_frag);
-            }
-        }
-
-        fragments
-    }
-
-    /// Estimate the physical pages that are within this range, on this shard.  This returns
-    /// u32::MAX if the range spans relations: this return value should be interpreted as "large".
-    pub fn page_count(&self) -> u32 {
-        // Special cases for single keys like logical sizes
-        if self.range.end == self.range.start.add(1) {
-            return if self.shard_identity.is_key_disposable(&self.range.start) {
-                0
-            } else {
-                1
-            };
-        }
-
-        // We can only do an authentic calculation of contiguous key ranges
-        if !is_contiguous_range(&self.range) {
-            return u32::MAX;
-        }
-
-        // Special case for single sharded tenants: our logical and physical sizes are the same
-        if self.shard_identity.count < ShardCount::new(2) {
-            return contiguous_range_len(&self.range);
-        }
-
-        // Normal path: step through stripes and part-stripes in the range, evaluate whether each one belongs
-        // to Self, and add the stripe's block count to our total if so.
-        let mut result: u64 = 0;
-        let mut cursor = self.range.start;
-        while cursor < self.range.end {
-            // Count up to the next stripe_size boundary or end of range
-            let advance_by = self.distance_to_next_boundary(cursor);
-
-            // If this blocks in this stripe belong to us, add them to our count
-            if !self.shard_identity.is_key_disposable(&cursor) {
-                result += advance_by as u64;
-            }
-
-            cursor = cursor.add(advance_by);
-        }
-
-        if result > u32::MAX as u64 {
-            u32::MAX
-        } else {
-            result as u32
-        }
-    }
-
-    /// Advance the cursor to the next potential fragment boundary: this is either
-    /// a stripe boundary, or the end of the range.
-    fn distance_to_next_boundary(&self, cursor: Key) -> u32 {
-        let distance_to_range_end = contiguous_range_len(&(cursor..self.range.end));
-
-        if self.shard_identity.count < ShardCount::new(2) {
-            // Optimization: don't bother stepping through stripes if the tenant isn't sharded.
-            return distance_to_range_end;
-        }
-
-        if cursor.field6 == 0xffffffff {
-            // We are wrapping from one relation's logical size to the next relation's first data block
-            return 1;
-        }
-
-        let stripe_index = cursor.field6 / self.shard_identity.stripe_size.0;
-        let stripe_remainder = self.shard_identity.stripe_size.0
-            - (cursor.field6 - stripe_index * self.shard_identity.stripe_size.0);
-
-        if cfg!(debug_assertions) {
-            // We should never overflow field5 and field6 -- our callers check this earlier
-            // and would have returned their u32::MAX cases if the input range violated this.
-            let next_cursor = cursor.add(stripe_remainder);
-            debug_assert!(
-                next_cursor.field1 == cursor.field1
-                    && next_cursor.field2 == cursor.field2
-                    && next_cursor.field3 == cursor.field3
-                    && next_cursor.field4 == cursor.field4
-                    && next_cursor.field5 == cursor.field5
-            )
-        }
-
-        std::cmp::min(stripe_remainder, distance_to_range_end)
-    }
-
-    /// Whereas `page_count` estimates the number of pages physically in this range on this shard,
-    /// this function simply calculates the number of pages in the space, without accounting for those
-    /// pages that would not actually be stored on this node.
-    ///
-    /// Don't use this function in code that works with physical entities like layer files.
-    fn raw_size(range: &Range<Key>) -> u32 {
-        if is_contiguous_range(range) {
-            contiguous_range_len(range)
-        } else {
-            u32::MAX
-        }
-    }
-}
-
 impl KeySpace {
-    /// Create a key space with a single range.
-    pub fn single(key_range: Range<Key>) -> Self {
-        Self {
-            ranges: vec![key_range],
-        }
-    }
-
+    ///
    /// Partition a key space into roughly chunks of roughly 'target_size' bytes
    /// in each partition.
    ///
-    pub fn partition(&self, shard_identity: &ShardIdentity, target_size: u64) -> KeyPartitioning {
+    pub fn partition(&self, target_size: u64) -> KeyPartitioning {
        // Assume that each value is 8k in size.
-        let target_nblocks = (target_size / BLCKSZ as u64) as u32;
+        let target_nblocks = (target_size / BLCKSZ as u64) as usize;

        let mut parts = Vec::new();
        let mut current_part = Vec::new();
        let mut current_part_size: usize = 0;
        for range in &self.ranges {
-            // While doing partitioning, wrap the range in ShardedRange so that our size calculations
-            // will respect shard striping rather than assuming all keys within a range are present.
-            let range = ShardedRange::new(range.clone(), shard_identity);
-
-            // Chunk up the range into parts that each contain up to target_size local blocks
-            for (frag_on_shard_size, frag_range) in range.fragment(target_nblocks) {
-                // If appending the next contiguous range in the keyspace to the current
-                // partition would cause it to be too large, and our current partition
-                // covers at least one block that is physically present in this shard,
-                // then start a new partition
-                if current_part_size + frag_on_shard_size as usize > target_nblocks as usize
-                    && current_part_size > 0
-                {
-                    parts.push(KeySpace {
-                        ranges: current_part,
-                    });
-                    current_part = Vec::new();
-                    current_part_size = 0;
-                }
-                current_part.push(frag_range.start..frag_range.end);
-                current_part_size += frag_on_shard_size as usize;
+            // If appending the next contiguous range in the keyspace to the current
+            // partition would cause it to be too large, start a new partition.
+            let this_size = key_range_size(range) as usize;
+            if current_part_size + this_size > target_nblocks && !current_part.is_empty() {
+                parts.push(KeySpace {
+                    ranges: current_part,
+                });
+                current_part = Vec::new();
+                current_part_size = 0;
            }
+
+            // If the next range is larger than 'target_size', split it into
+            // 'target_size' chunks.
+            let mut remain_size = this_size;
+            let mut start = range.start;
+            while remain_size > target_nblocks {
+                let next = start.add(target_nblocks as u32);
+                parts.push(KeySpace {
+                    ranges: vec![start..next],
+                });
+                start = next;
+                remain_size -= target_nblocks
+            }
+            current_part.push(start..range.end);
+            current_part_size += remain_size;
        }

        // add last partition that wasn't full yet.
@@ -298,10 +64,6 @@ impl KeySpace {
        KeyPartitioning { parts }
    }

-    pub fn is_empty(&self) -> bool {
-        self.total_raw_size() == 0
-    }
-
    /// Merge another keyspace into the current one.
    /// Note: the keyspaces must not ovelap (enforced via assertions)
    pub fn merge(&mut self, other: &KeySpace) {
@@ -332,13 +94,12 @@ impl KeySpace {

    /// Remove all keys in `other` from `self`.
    /// This can involve splitting or removing of existing ranges.
-    /// Returns the removed keyspace
-    pub fn remove_overlapping_with(&mut self, other: &KeySpace) -> KeySpace {
+    pub fn remove_overlapping_with(&mut self, other: &KeySpace) {
        let (self_start, self_end) = match (self.start(), self.end()) {
            (Some(start), Some(end)) => (start, end),
            _ => {
                // self is empty
-                return KeySpace::default();
+                return;
            }
        };

@@ -351,37 +112,30 @@ impl KeySpace {
            .skip_while(|range| self_start >= range.end)
            .take_while(|range| self_end > range.start);

-        let mut removed_accum = KeySpaceRandomAccum::new();
        for range in other_ranges {
            while let Some(overlap_at) = self.overlaps_at(range) {
                let overlapped = self.ranges[overlap_at].clone();

                if overlapped.start < range.start && overlapped.end <= range.end {
                    // Higher part of the range is completely overlapped.
-                    removed_accum.add_range(range.start..self.ranges[overlap_at].end);
                    self.ranges[overlap_at].end = range.start;
                }
                if overlapped.start >= range.start && overlapped.end > range.end {
                    // Lower part of the range is completely overlapped.
-                    removed_accum.add_range(self.ranges[overlap_at].start..range.end);
                    self.ranges[overlap_at].start = range.end;
                }
                if overlapped.start < range.start && overlapped.end > range.end {
                    // Middle part of the range is overlapped.
-                    removed_accum.add_range(range.clone());
                    self.ranges[overlap_at].end = range.start;
                    self.ranges
                        .insert(overlap_at + 1, range.end..overlapped.end);
                }
                if overlapped.start >= range.start && overlapped.end <= range.end {
                    // Whole range is overlapped
-                    removed_accum.add_range(self.ranges[overlap_at].clone());
                    self.ranges.remove(overlap_at);
                }
            }
        }
-
-        removed_accum.to_keyspace()
    }

    pub fn start(&self) -> Option<Key> {
@@ -392,11 +146,11 @@ impl KeySpace {
        self.ranges.last().map(|range| range.end)
    }

-    /// The size of the keyspace in pages, before accounting for sharding
-    pub fn total_raw_size(&self) -> usize {
+    #[allow(unused)]
+    pub fn total_size(&self) -> usize {
        self.ranges
            .iter()
-            .map(|range| ShardedRange::raw_size(range) as usize)
+            .map(|range| key_range_size(range) as usize)
            .sum()
    }

@@ -416,11 +170,6 @@ impl KeySpace {
    pub fn overlaps(&self, range: &Range<Key>) -> bool {
        self.overlaps_at(range).is_some()
    }
-
-    /// Check if the keyspace contains a key
-    pub fn contains(&self, key: &Key) -> bool {
-        self.overlaps(&(*key..key.next()))
-    }
 }

 ///
@@ -470,7 +219,7 @@ impl KeySpaceAccum {

    #[inline(always)]
    pub fn add_range(&mut self, range: Range<Key>) {
-        self.size += ShardedRange::raw_size(&range) as u64;
+        self.size += key_range_size(&range) as u64;

        match self.accum.as_mut() {
            Some(accum) => {
@@ -502,9 +251,7 @@ impl KeySpaceAccum {
        std::mem::take(self).to_keyspace()
    }

-    // The total number of keys in this object, ignoring any sharding effects that might cause some of
-    // the keys to be omitted in storage on this shard.
-    pub fn raw_size(&self) -> u64 {
+    pub fn size(&self) -> u64 {
        self.size
    }
 }
@@ -560,19 +307,36 @@ impl KeySpaceRandomAccum {
    }
 }

+#[inline(always)]
+pub fn key_range_size(key_range: &Range<Key>) -> u32 {
+    let start = key_range.start;
+    let end = key_range.end;
+
+    if end.field1 != start.field1
+        || end.field2 != start.field2
+        || end.field3 != start.field3
+        || end.field4 != start.field4
+    {
+        return u32::MAX;
+    }
+
+    let start = (start.field5 as u64) << 32 | start.field6 as u64;
+    let end = (end.field5 as u64) << 32 | end.field6 as u64;
+
+    let diff = end - start;
+    if diff > u32::MAX as u64 {
+        u32::MAX
+    } else {
+        diff as u32
+    }
+}
+
 pub fn singleton_range(key: Key) -> Range<Key> {
    key..key.next()
 }

 #[cfg(test)]
 mod tests {
-    use rand::{RngCore, SeedableRng};
-
-    use crate::{
-        models::ShardParameters,
-        shard::{ShardCount, ShardNumber},
-    };
-
    use super::*;
    use std::fmt::Write;

@@ -615,17 +379,14 @@ mod tests {
            accum.add_range(range.clone());
        }

-        let expected_size: u64 = ranges
-            .iter()
-            .map(|r| ShardedRange::raw_size(r) as u64)
-            .sum();
-        assert_eq!(accum.raw_size(), expected_size);
+        let expected_size: u64 = ranges.iter().map(|r| key_range_size(r) as u64).sum();
+        assert_eq!(accum.size(), expected_size);

        assert_ks_eq(&accum.consume_keyspace(), ranges.clone());
-        assert_eq!(accum.raw_size(), 0);
+        assert_eq!(accum.size(), 0);

        assert_ks_eq(&accum.consume_keyspace(), vec![]);
-        assert_eq!(accum.raw_size(), 0);
+        assert_eq!(accum.size(), 0);

        for range in &ranges {
            accum.add_range(range.clone());
@@ -792,16 +553,7 @@ mod tests {
                Key::from_i128(11)..Key::from_i128(13),
            ],
        };
-        let removed = key_space1.remove_overlapping_with(&key_space2);
-        let removed_expected = KeySpace {
-            ranges: vec![
-                Key::from_i128(2)..Key::from_i128(3),
-                Key::from_i128(6)..Key::from_i128(7),
-                Key::from_i128(11)..Key::from_i128(12),
-            ],
-        };
-        assert_eq!(removed, removed_expected);
-
+        key_space1.remove_overlapping_with(&key_space2);
        assert_eq!(
            key_space1.ranges,
            vec![
@@ -831,17 +583,7 @@ mod tests {
                Key::from_i128(14)..Key::from_i128(17),
            ],
        };
-
-        let removed = key_space1.remove_overlapping_with(&key_space2);
-        let removed_expected = KeySpace {
-            ranges: vec![
-                Key::from_i128(3)..Key::from_i128(5),
-                Key::from_i128(8)..Key::from_i128(10),
-                Key::from_i128(14)..Key::from_i128(15),
-            ],
-        };
-        assert_eq!(removed, removed_expected);
-
+        key_space1.remove_overlapping_with(&key_space2);
        assert_eq!(
            key_space1.ranges,
            vec![
@@ -868,11 +610,7 @@ mod tests {
                Key::from_i128(15)..Key::from_i128(17),
            ],
        };
-
-        let removed = key_space1.remove_overlapping_with(&key_space2);
-        let removed_expected = KeySpace::default();
-        assert_eq!(removed, removed_expected);
-
+        key_space1.remove_overlapping_with(&key_space2);
        assert_eq!(
            key_space1.ranges,
            vec![
@@ -899,17 +637,7 @@ mod tests {
        let key_space2 = KeySpace {
            ranges: vec![Key::from_i128(9)..Key::from_i128(19)],
        };
-
-        let removed = key_space1.remove_overlapping_with(&key_space2);
-        let removed_expected = KeySpace {
-            ranges: vec![
-                Key::from_i128(9)..Key::from_i128(10),
-                Key::from_i128(12)..Key::from_i128(15),
-                Key::from_i128(17)..Key::from_i128(19),
-            ],
-        };
-        assert_eq!(removed, removed_expected);
-
+        key_space1.remove_overlapping_with(&key_space2);
        assert_eq!(
            key_space1.ranges,
            vec![
@@ -922,412 +650,4 @@ mod tests {
            ]
        );
    }
-    #[test]
-    fn sharded_range_relation_gap() {
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(0),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-
-        let range = ShardedRange::new(
-            Range {
-                start: Key::from_hex("000000067F00000005000040100300000000").unwrap(),
-                end: Key::from_hex("000000067F00000005000040130000004000").unwrap(),
-            },
-            &shard_identity,
-        );
-
-        // Key range spans relations, expect MAX
-        assert_eq!(range.page_count(), u32::MAX);
-    }
-
-    #[test]
-    fn shard_identity_keyspaces_single_key() {
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(1),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-
-        let range = ShardedRange::new(
-            Range {
-                start: Key::from_hex("000000067f000000010000007000ffffffff").unwrap(),
-                end: Key::from_hex("000000067f00000001000000700100000000").unwrap(),
-            },
-            &shard_identity,
-        );
-        // Single-key range on logical size key
-        assert_eq!(range.page_count(), 1);
-    }
-
-    /// Test the helper that we use to identify ranges which go outside the data blocks of a single relation
-    #[test]
-    fn contiguous_range_check() {
-        assert!(!is_contiguous_range(
-            &(Key::from_hex("000000067f00000001000004df00fffffffe").unwrap()
-                ..Key::from_hex("000000067f00000001000004df0100000003").unwrap())
-        ),);
-
-        // The ranges goes all the way up to the 0xffffffff, including it: this is
-        // not considered a rel block range because 0xffffffff stores logical sizes,
-        // not blocks.
-        assert!(!is_contiguous_range(
-            &(Key::from_hex("000000067f00000001000004df00fffffffe").unwrap()
-                ..Key::from_hex("000000067f00000001000004df0100000000").unwrap())
-        ),);
-
-        // Keys within the normal data region of a relation
-        assert!(is_contiguous_range(
-            &(Key::from_hex("000000067f00000001000004df0000000000").unwrap()
-                ..Key::from_hex("000000067f00000001000004df0000000080").unwrap())
-        ),);
-
-        // The logical size key of one forkno, then some blocks in the next
-        assert!(is_contiguous_range(
-            &(Key::from_hex("000000067f00000001000004df00ffffffff").unwrap()
-                ..Key::from_hex("000000067f00000001000004df0100000080").unwrap())
-        ),);
-    }
-
-    #[test]
-    fn shard_identity_keyspaces_forkno_gap() {
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(1),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-
-        let range = ShardedRange::new(
-            Range {
-                start: Key::from_hex("000000067f00000001000004df00fffffffe").unwrap(),
-                end: Key::from_hex("000000067f00000001000004df0100000003").unwrap(),
-            },
-            &shard_identity,
-        );
-
-        // Range spanning the end of one forkno and the start of the next: we do not attempt to
-        // calculate a valid size, because we have no way to know if they keys between start
-        // and end are actually in use.
-        assert_eq!(range.page_count(), u32::MAX);
-    }
-
-    #[test]
-    fn shard_identity_keyspaces_one_relation() {
-        for shard_number in 0..4 {
-            let shard_identity = ShardIdentity::new(
-                ShardNumber(shard_number),
-                ShardCount::new(4),
-                ShardParameters::DEFAULT_STRIPE_SIZE,
-            )
-            .unwrap();
-
-            let range = ShardedRange::new(
-                Range {
-                    start: Key::from_hex("000000067f00000001000000ae0000000000").unwrap(),
-                    end: Key::from_hex("000000067f00000001000000ae0000000001").unwrap(),
-                },
-                &shard_identity,
-            );
-
-            // Very simple case: range covering block zero of one relation, where that block maps to shard zero
-            if shard_number == 0 {
-                assert_eq!(range.page_count(), 1);
-            } else {
-                // Other shards should perceive the range's size as zero
-                assert_eq!(range.page_count(), 0);
-            }
-        }
-    }
-
-    /// Test helper: construct a ShardedRange and call fragment() on it, returning
-    /// the total page count in the range and the fragments.
-    fn do_fragment(
-        range_start: Key,
-        range_end: Key,
-        shard_identity: &ShardIdentity,
-        target_nblocks: u32,
-    ) -> (u32, Vec<(u32, Range<Key>)>) {
-        let range = ShardedRange::new(
-            Range {
-                start: range_start,
-                end: range_end,
-            },
-            shard_identity,
-        );
-
-        let page_count = range.page_count();
-        let fragments = range.fragment(target_nblocks);
-
-        // Invariant: we always get at least one fragment
-        assert!(!fragments.is_empty());
-
-        // Invariant: the first/last fragment start/end should equal the input start/end
-        assert_eq!(fragments.first().unwrap().1.start, range_start);
-        assert_eq!(fragments.last().unwrap().1.end, range_end);
-
-        if page_count > 0 {
-            // Invariant: every fragment must contain at least one shard-local page, if the
-            // total range contains at least one shard-local page
-            let all_nonzero = fragments.iter().all(|f| f.0 > 0);
-            if !all_nonzero {
-                eprintln!("Found a zero-length fragment: {:?}", fragments);
-            }
-            assert!(all_nonzero);
-        } else {
-            // A range with no shard-local pages should always be returned as a single fragment
-            assert_eq!(fragments, vec![(0, range_start..range_end)]);
-        }
-
-        // Invariant: fragments must be ordered and non-overlapping
-        let mut last: Option<Range<Key>> = None;
-        for frag in &fragments {
-            if let Some(last) = last {
-                assert!(frag.1.start >= last.end);
-                assert!(frag.1.start > last.start);
-            }
-            last = Some(frag.1.clone())
-        }
-
-        // Invariant: fragments respect target_nblocks
-        for frag in &fragments {
-            assert!(frag.0 == u32::MAX || frag.0 <= target_nblocks);
-        }
-
-        (page_count, fragments)
-    }
-
-    /// Really simple tests for fragment(), on a range that just contains a single stripe
-    /// for a single tenant.
-    #[test]
-    fn sharded_range_fragment_simple() {
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(0),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-
-        // A range which we happen to know covers exactly one stripe which belongs to this shard
-        let input_start = Key::from_hex("000000067f00000001000000ae0000000000").unwrap();
-        let input_end = Key::from_hex("000000067f00000001000000ae0000008000").unwrap();
-
-        // Ask for stripe_size blocks, we get the whole stripe
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 32768),
-            (32768, vec![(32768, input_start..input_end)])
-        );
-
-        // Ask for more, we still get the whole stripe
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 10000000),
-            (32768, vec![(32768, input_start..input_end)])
-        );
-
-        // Ask for target_nblocks of half the stripe size, we get two halves
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 16384),
-            (
-                32768,
-                vec![
-                    (16384, input_start..input_start.add(16384)),
-                    (16384, input_start.add(16384)..input_end)
-                ]
-            )
-        );
-    }
-
-    #[test]
-    fn sharded_range_fragment_multi_stripe() {
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(0),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-
-        // A range which covers multiple stripes, exactly one of which belongs to the current shard.
-        let input_start = Key::from_hex("000000067f00000001000000ae0000000000").unwrap();
-        let input_end = Key::from_hex("000000067f00000001000000ae0000020000").unwrap();
-        // Ask for all the blocks, get a fragment that covers the whole range but reports
-        // its size to be just the blocks belonging to our shard.
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 131072),
-            (32768, vec![(32768, input_start..input_end)])
-        );
-
-        // Ask for a sub-stripe quantity
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 16000),
-            (
-                32768,
-                vec![
-                    (16000, input_start..input_start.add(16000)),
-                    (16000, input_start.add(16000)..input_start.add(32000)),
-                    (768, input_start.add(32000)..input_end),
-                ]
-            )
-        );
-
-        // Try on a range that starts slightly after our owned stripe
-        assert_eq!(
-            do_fragment(input_start.add(1), input_end, &shard_identity, 131072),
-            (32767, vec![(32767, input_start.add(1)..input_end)])
-        );
-    }
-
-    /// Test our calculations work correctly when we start a range from the logical size key of
-    /// a previous relation.
-    #[test]
-    fn sharded_range_fragment_starting_from_logical_size() {
-        let input_start = Key::from_hex("000000067f00000001000000ae00ffffffff").unwrap();
-        let input_end = Key::from_hex("000000067f00000001000000ae0100008000").unwrap();
-
-        // Shard 0 owns the first stripe in the relation, and the preceding logical size is shard local too
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(0),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 0x10000),
-            (0x8001, vec![(0x8001, input_start..input_end)])
-        );
-
-        // Shard 1 does not own the first stripe in the relation, but it does own the logical size (all shards
-        // store all logical sizes)
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(1),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 0x10000),
-            (0x1, vec![(0x1, input_start..input_end)])
-        );
-    }
-
-    /// Test that ShardedRange behaves properly when used on un-sharded data
-    #[test]
-    fn sharded_range_fragment_unsharded() {
-        let shard_identity = ShardIdentity::unsharded();
-
-        let input_start = Key::from_hex("000000067f00000001000000ae0000000000").unwrap();
-        let input_end = Key::from_hex("000000067f00000001000000ae0000010000").unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 0x8000),
-            (
-                0x10000,
-                vec![
-                    (0x8000, input_start..input_start.add(0x8000)),
-                    (0x8000, input_start.add(0x8000)..input_start.add(0x10000))
-                ]
-            )
-        );
-    }
-
-    #[test]
-    fn sharded_range_fragment_cross_relation() {
-        let shard_identity = ShardIdentity::unsharded();
-
-        // A range that spans relations: expect fragmentation to give up and return a u32::MAX size
-        let input_start = Key::from_hex("000000067f00000001000000ae0000000000").unwrap();
-        let input_end = Key::from_hex("000000068f00000001000000ae0000010000").unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 0x8000),
-            (u32::MAX, vec![(u32::MAX, input_start..input_end),])
-        );
-
-        // Same, but using a sharded identity
-        let shard_identity = ShardIdentity::new(
-            ShardNumber(0),
-            ShardCount::new(4),
-            ShardParameters::DEFAULT_STRIPE_SIZE,
-        )
-        .unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 0x8000),
-            (u32::MAX, vec![(u32::MAX, input_start..input_end),])
-        );
-    }
-
-    #[test]
-    fn sharded_range_fragment_tiny_nblocks() {
-        let shard_identity = ShardIdentity::unsharded();
-
-        // A range that spans relations: expect fragmentation to give up and return a u32::MAX size
-        let input_start = Key::from_hex("000000067F00000001000004E10000000000").unwrap();
-        let input_end = Key::from_hex("000000067F00000001000004E10000000038").unwrap();
-        assert_eq!(
-            do_fragment(input_start, input_end, &shard_identity, 16),
-            (
-                0x38,
-                vec![
-                    (16, input_start..input_start.add(16)),
-                    (16, input_start.add(16)..input_start.add(32)),
-                    (16, input_start.add(32)..input_start.add(48)),
-                    (8, input_start.add(48)..input_end),
-                ]
-            )
-        );
-    }
-
-    #[test]
-    fn sharded_range_fragment_fuzz() {
-        // Use a fixed seed: we don't want to explicitly pick values, but we do want
-        // the test to be reproducible.
-        let mut prng = rand::rngs::StdRng::seed_from_u64(0xdeadbeef);
-
-        for _i in 0..1000 {
-            let shard_identity = if prng.next_u32() % 2 == 0 {
-                ShardIdentity::unsharded()
-            } else {
-                let shard_count = prng.next_u32() % 127 + 1;
-                ShardIdentity::new(
-                    ShardNumber((prng.next_u32() % shard_count) as u8),
-                    ShardCount::new(shard_count as u8),
-                    ShardParameters::DEFAULT_STRIPE_SIZE,
-                )
-                .unwrap()
-            };
-
-            let target_nblocks = prng.next_u32() % 65536 + 1;
-
-            let start_offset = prng.next_u32() % 16384;
-
-            // Try ranges up to 4GiB in size, that are always at least 1
-            let range_size = prng.next_u32() % 8192 + 1;
-
-            // A range that spans relations: expect fragmentation to give up and return a u32::MAX size
-            let input_start = Key::from_hex("000000067F00000001000004E10000000000")
-                .unwrap()
-                .add(start_offset);
-            let input_end = input_start.add(range_size);
-
-            // This test's main success conditions are the invariants baked into do_fragment
-            let (_total_size, fragments) =
-                do_fragment(input_start, input_end, &shard_identity, target_nblocks);
-
-            // Pick a random key within the range and check it appears in the output
-            let example_key = input_start.add(prng.next_u32() % range_size);
-
-            // Panic on unwrap if it isn't found
-            let example_key_frag = fragments
-                .iter()
-                .find(|f| f.1.contains(&example_key))
-                .unwrap();
-
-            // Check that the fragment containing our random key has a nonzero size if
-            // that key is shard-local
-            let example_key_local = !shard_identity.is_key_disposable(&example_key);
-            if example_key_local {
-                assert!(example_key_frag.0 > 0);
-            }
-        }
-    }
 }
--- a/libs/pageserver_api/src/models.rs
+++ b/libs/pageserver_api/src/models.rs
@@ -303,7 +303,6 @@ pub struct TenantConfig {
    pub lazy_slru_download: Option<bool>,
    pub timeline_get_throttle: Option<ThrottleConfig>,
    pub image_layer_creation_check_threshold: Option<u8>,
-    pub switch_to_aux_file_v2: Option<bool>,
 }

 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
@@ -430,7 +429,6 @@ pub struct StatusResponse {
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(deny_unknown_fields)]
 pub struct TenantLocationConfigRequest {
-    #[serde(skip_serializing_if = "Option::is_none")]
    pub tenant_id: Option<TenantShardId>,
    #[serde(flatten)]
    pub config: LocationConfig, // as we have a flattened field, we should reject all unknown fields in it
@@ -782,17 +780,6 @@ pub struct SecondaryProgress {
    pub bytes_total: u64,
 }

-#[derive(Serialize, Deserialize, Debug)]
-pub struct TenantScanRemoteStorageShard {
-    pub tenant_shard_id: TenantShardId,
-    pub generation: Option<u32>,
-}
-
-#[derive(Serialize, Deserialize, Debug, Default)]
-pub struct TenantScanRemoteStorageResponse {
-    pub shards: Vec<TenantScanRemoteStorageShard>,
-}
-
 pub mod virtual_file {
    #[derive(
        Copy,
@@ -860,72 +847,39 @@ impl TryFrom<u8> for PagestreamBeMessageTag {
    }
 }

-// In the V2 protocol version, a GetPage request contains two LSN values:
-//
-// request_lsn: Get the page version at this point in time.  Lsn::Max is a special value that means
-// "get the latest version present". It's used by the primary server, which knows that no one else
-// is writing WAL. 'not_modified_since' must be set to a proper value even if request_lsn is
-// Lsn::Max. Standby servers use the current replay LSN as the request LSN.
-//
-// not_modified_since: Hint to the pageserver that the client knows that the page has not been
-// modified between 'not_modified_since' and the request LSN. It's always correct to set
-// 'not_modified_since equal' to 'request_lsn' (unless Lsn::Max is used as the 'request_lsn'), but
-// passing an earlier LSN can speed up the request, by allowing the pageserver to process the
-// request without waiting for 'request_lsn' to arrive.
-//
-// The legacy V1 interface contained only one LSN, and a boolean 'latest' flag. The V1 interface was
-// sufficient for the primary; the 'lsn' was equivalent to the 'not_modified_since' value, and
-// 'latest' was set to true. The V2 interface was added because there was no correct way for a
-// standby to request a page at a particular non-latest LSN, and also include the
-// 'not_modified_since' hint. That led to an awkward choice of either using an old LSN in the
-// request, if the standby knows that the page hasn't been modified since, and risk getting an error
-// if that LSN has fallen behind the GC horizon, or requesting the current replay LSN, which could
-// require the pageserver unnecessarily to wait for the WAL to arrive up to that point. The new V2
-// interface allows sending both LSNs, and let the pageserver do the right thing. There is no
-// difference in the responses between V1 and V2.
-//
-// The Request structs below reflect the V2 interface. If V1 is used, the parse function
-// maps the old format requests to the new format.
-//
-#[derive(Clone, Copy)]
-pub enum PagestreamProtocolVersion {
-    V1,
-    V2,
-}
-
 #[derive(Debug, PartialEq, Eq)]
 pub struct PagestreamExistsRequest {
-    pub request_lsn: Lsn,
-    pub not_modified_since: Lsn,
+    pub latest: bool,
+    pub lsn: Lsn,
    pub rel: RelTag,
 }

 #[derive(Debug, PartialEq, Eq)]
 pub struct PagestreamNblocksRequest {
-    pub request_lsn: Lsn,
-    pub not_modified_since: Lsn,
+    pub latest: bool,
+    pub lsn: Lsn,
    pub rel: RelTag,
 }

 #[derive(Debug, PartialEq, Eq)]
 pub struct PagestreamGetPageRequest {
-    pub request_lsn: Lsn,
-    pub not_modified_since: Lsn,
+    pub latest: bool,
+    pub lsn: Lsn,
    pub rel: RelTag,
    pub blkno: u32,
 }

 #[derive(Debug, PartialEq, Eq)]
 pub struct PagestreamDbSizeRequest {
-    pub request_lsn: Lsn,
-    pub not_modified_since: Lsn,
+    pub latest: bool,
+    pub lsn: Lsn,
    pub dbnode: u32,
 }

 #[derive(Debug, PartialEq, Eq)]
 pub struct PagestreamGetSlruSegmentRequest {
-    pub request_lsn: Lsn,
-    pub not_modified_since: Lsn,
+    pub latest: bool,
+    pub lsn: Lsn,
    pub kind: u8,
    pub segno: u32,
 }
@@ -972,16 +926,14 @@ pub struct TenantHistorySize {
 }

 impl PagestreamFeMessage {
-    /// Serialize a compute -> pageserver message. This is currently only used in testing
-    /// tools. Always uses protocol version 2.
    pub fn serialize(&self) -> Bytes {
        let mut bytes = BytesMut::new();

        match self {
            Self::Exists(req) => {
                bytes.put_u8(0);
-                bytes.put_u64(req.request_lsn.0);
-                bytes.put_u64(req.not_modified_since.0);
+                bytes.put_u8(u8::from(req.latest));
+                bytes.put_u64(req.lsn.0);
                bytes.put_u32(req.rel.spcnode);
                bytes.put_u32(req.rel.dbnode);
                bytes.put_u32(req.rel.relnode);
@@ -990,8 +942,8 @@ impl PagestreamFeMessage {

            Self::Nblocks(req) => {
                bytes.put_u8(1);
-                bytes.put_u64(req.request_lsn.0);
-                bytes.put_u64(req.not_modified_since.0);
+                bytes.put_u8(u8::from(req.latest));
+                bytes.put_u64(req.lsn.0);
                bytes.put_u32(req.rel.spcnode);
                bytes.put_u32(req.rel.dbnode);
                bytes.put_u32(req.rel.relnode);
@@ -1000,8 +952,8 @@ impl PagestreamFeMessage {

            Self::GetPage(req) => {
                bytes.put_u8(2);
-                bytes.put_u64(req.request_lsn.0);
-                bytes.put_u64(req.not_modified_since.0);
+                bytes.put_u8(u8::from(req.latest));
+                bytes.put_u64(req.lsn.0);
                bytes.put_u32(req.rel.spcnode);
                bytes.put_u32(req.rel.dbnode);
                bytes.put_u32(req.rel.relnode);
@@ -1011,15 +963,15 @@ impl PagestreamFeMessage {

            Self::DbSize(req) => {
                bytes.put_u8(3);
-                bytes.put_u64(req.request_lsn.0);
-                bytes.put_u64(req.not_modified_since.0);
+                bytes.put_u8(u8::from(req.latest));
+                bytes.put_u64(req.lsn.0);
                bytes.put_u32(req.dbnode);
            }

            Self::GetSlruSegment(req) => {
                bytes.put_u8(4);
-                bytes.put_u64(req.request_lsn.0);
-                bytes.put_u64(req.not_modified_since.0);
+                bytes.put_u8(u8::from(req.latest));
+                bytes.put_u64(req.lsn.0);
                bytes.put_u8(req.kind);
                bytes.put_u32(req.segno);
            }
@@ -1028,40 +980,18 @@ impl PagestreamFeMessage {
        bytes.into()
    }

-    pub fn parse<R: std::io::Read>(
-        body: &mut R,
-        protocol_version: PagestreamProtocolVersion,
-    ) -> anyhow::Result<PagestreamFeMessage> {
+    pub fn parse<R: std::io::Read>(body: &mut R) -> anyhow::Result<PagestreamFeMessage> {
+        // TODO these gets can fail
+
        // these correspond to the NeonMessageTag enum in pagestore_client.h
        //
        // TODO: consider using protobuf or serde bincode for less error prone
        // serialization.
        let msg_tag = body.read_u8()?;
-
-        let (request_lsn, not_modified_since) = match protocol_version {
-            PagestreamProtocolVersion::V2 => (
-                Lsn::from(body.read_u64::<BigEndian>()?),
-                Lsn::from(body.read_u64::<BigEndian>()?),
-            ),
-            PagestreamProtocolVersion::V1 => {
-                // In the old protocol, each message starts with a boolean 'latest' flag,
-                // followed by 'lsn'. Convert that to the two LSNs, 'request_lsn' and
-                // 'not_modified_since', used in the new protocol version.
-                let latest = body.read_u8()? != 0;
-                let request_lsn = Lsn::from(body.read_u64::<BigEndian>()?);
-                if latest {
-                    (Lsn::MAX, request_lsn) // get latest version
-                } else {
-                    (request_lsn, request_lsn) // get version at specified LSN
-                }
-            }
-        };
-
-        // The rest of the messages are the same between V1 and V2
        match msg_tag {
            0 => Ok(PagestreamFeMessage::Exists(PagestreamExistsRequest {
-                request_lsn,
-                not_modified_since,
+                latest: body.read_u8()? != 0,
+                lsn: Lsn::from(body.read_u64::<BigEndian>()?),
                rel: RelTag {
                    spcnode: body.read_u32::<BigEndian>()?,
                    dbnode: body.read_u32::<BigEndian>()?,
@@ -1070,8 +1000,8 @@ impl PagestreamFeMessage {
                },
            })),
            1 => Ok(PagestreamFeMessage::Nblocks(PagestreamNblocksRequest {
-                request_lsn,
-                not_modified_since,
+                latest: body.read_u8()? != 0,
+                lsn: Lsn::from(body.read_u64::<BigEndian>()?),
                rel: RelTag {
                    spcnode: body.read_u32::<BigEndian>()?,
                    dbnode: body.read_u32::<BigEndian>()?,
@@ -1080,8 +1010,8 @@ impl PagestreamFeMessage {
                },
            })),
            2 => Ok(PagestreamFeMessage::GetPage(PagestreamGetPageRequest {
-                request_lsn,
-                not_modified_since,
+                latest: body.read_u8()? != 0,
+                lsn: Lsn::from(body.read_u64::<BigEndian>()?),
                rel: RelTag {
                    spcnode: body.read_u32::<BigEndian>()?,
                    dbnode: body.read_u32::<BigEndian>()?,
@@ -1091,14 +1021,14 @@ impl PagestreamFeMessage {
                blkno: body.read_u32::<BigEndian>()?,
            })),
            3 => Ok(PagestreamFeMessage::DbSize(PagestreamDbSizeRequest {
-                request_lsn,
-                not_modified_since,
+                latest: body.read_u8()? != 0,
+                lsn: Lsn::from(body.read_u64::<BigEndian>()?),
                dbnode: body.read_u32::<BigEndian>()?,
            })),
            4 => Ok(PagestreamFeMessage::GetSlruSegment(
                PagestreamGetSlruSegmentRequest {
-                    request_lsn,
-                    not_modified_since,
+                    latest: body.read_u8()? != 0,
+                    lsn: Lsn::from(body.read_u64::<BigEndian>()?),
                    kind: body.read_u8()?,
                    segno: body.read_u32::<BigEndian>()?,
                },
@@ -1226,8 +1156,8 @@ mod tests {
        // Test serialization/deserialization of PagestreamFeMessage
        let messages = vec![
            PagestreamFeMessage::Exists(PagestreamExistsRequest {
-                request_lsn: Lsn(4),
-                not_modified_since: Lsn(3),
+                latest: true,
+                lsn: Lsn(4),
                rel: RelTag {
                    forknum: 1,
                    spcnode: 2,
@@ -1236,8 +1166,8 @@ mod tests {
                },
            }),
            PagestreamFeMessage::Nblocks(PagestreamNblocksRequest {
-                request_lsn: Lsn(4),
-                not_modified_since: Lsn(4),
+                latest: false,
+                lsn: Lsn(4),
                rel: RelTag {
                    forknum: 1,
                    spcnode: 2,
@@ -1246,8 +1176,8 @@ mod tests {
                },
            }),
            PagestreamFeMessage::GetPage(PagestreamGetPageRequest {
-                request_lsn: Lsn(4),
-                not_modified_since: Lsn(3),
+                latest: true,
+                lsn: Lsn(4),
                rel: RelTag {
                    forknum: 1,
                    spcnode: 2,
@@ -1257,16 +1187,14 @@ mod tests {
                blkno: 7,
            }),
            PagestreamFeMessage::DbSize(PagestreamDbSizeRequest {
-                request_lsn: Lsn(4),
-                not_modified_since: Lsn(3),
+                latest: true,
+                lsn: Lsn(4),
                dbnode: 7,
            }),
        ];
        for msg in messages {
            let bytes = msg.serialize();
-            let reconstructed =
-                PagestreamFeMessage::parse(&mut bytes.reader(), PagestreamProtocolVersion::V2)
-                    .unwrap();
+            let reconstructed = PagestreamFeMessage::parse(&mut bytes.reader()).unwrap();
            assert!(msg == reconstructed);
        }
    }
--- a/libs/pageserver_api/src/shard.rs
+++ b/libs/pageserver_api/src/shard.rs
@@ -5,7 +5,6 @@ use crate::{
    models::ShardParameters,
 };
 use hex::FromHex;
-use postgres_ffi::relfile_utils::INIT_FORKNUM;
 use serde::{Deserialize, Serialize};
 use utils::id::TenantId;

@@ -451,7 +450,7 @@ impl ShardIdentity {
    /// An identity with number=0 count=0 is a "none" identity, which represents legacy
    /// tenants.  Modern single-shard tenants should not use this: they should
    /// have number=0 count=1.
-    pub const fn unsharded() -> Self {
+    pub fn unsharded() -> Self {
        Self {
            number: ShardNumber(0),
            count: ShardCount(0),
@@ -538,24 +537,6 @@ impl ShardIdentity {
        }
    }

-    /// Special case for issue `<https://github.com/neondatabase/neon/issues/7451>`
-    ///
-    /// When we fail to read a forknum block, this function tells us whether we may ignore the error
-    /// as a symptom of that issue.
-    pub fn is_key_buggy_forknum(&self, key: &Key) -> bool {
-        if !is_rel_block_key(key) || key.field5 != INIT_FORKNUM {
-            return false;
-        }
-
-        let mut hash = murmurhash32(key.field4);
-        hash = hash_combine(hash, murmurhash32(key.field6 / self.stripe_size.0));
-        let mapped_shard = ShardNumber((hash % self.count.0 as u32) as u8);
-
-        // The key may be affected by issue #7454: it is an initfork and it would not
-        // have mapped to shard 0 until we fixed that issue.
-        mapped_shard != ShardNumber(0)
-    }
-
    /// Return true if the key should be discarded if found in this shard's
    /// data store, e.g. during compaction after a split.
    ///
@@ -668,13 +649,7 @@ fn key_is_shard0(key: &Key) -> bool {
    // relation pages are distributed to shards other than shard zero. Everything else gets
    // stored on shard 0.  This guarantees that shard 0 can independently serve basebackup
    // requests, and any request other than those for particular blocks in relations.
-    //
-    // The only exception to this rule is "initfork" data -- this relates to postgres's UNLOGGED table
-    // type. These are special relations, usually with only 0 or 1 blocks, and we store them on shard 0
-    // because they must be included in basebackups.
-    let is_initfork = key.field5 == INIT_FORKNUM;
-
-    !is_rel_block_key(key) || is_initfork
+    !is_rel_block_key(key)
 }

 /// Provide the same result as the function in postgres `hashfn.h` with the same name
--- a/libs/postgres_ffi/src/lib.rs
+++ b/libs/postgres_ffi/src/lib.rs
@@ -118,9 +118,7 @@ pub use v14::bindings::{TimeLineID, TimestampTz, XLogRecPtr, XLogSegNo};
 // Likewise for these, although the assumption that these don't change is a little more iffy.
 pub use v14::bindings::{MultiXactOffset, MultiXactStatus};
 pub use v14::bindings::{PageHeaderData, XLogRecord};
-pub use v14::xlog_utils::{
-    XLOG_SIZE_OF_XLOG_LONG_PHD, XLOG_SIZE_OF_XLOG_RECORD, XLOG_SIZE_OF_XLOG_SHORT_PHD,
-};
+pub use v14::xlog_utils::{XLOG_SIZE_OF_XLOG_RECORD, XLOG_SIZE_OF_XLOG_SHORT_PHD};

 pub use v14::bindings::{CheckPoint, ControlFileData};

--- a/libs/postgres_ffi/wal_craft/src/lib.rs
+++ b/libs/postgres_ffi/wal_craft/src/lib.rs
@@ -4,9 +4,7 @@ use log::*;
 use postgres::types::PgLsn;
 use postgres::Client;
 use postgres_ffi::{WAL_SEGMENT_SIZE, XLOG_BLCKSZ};
-use postgres_ffi::{
-    XLOG_SIZE_OF_XLOG_LONG_PHD, XLOG_SIZE_OF_XLOG_RECORD, XLOG_SIZE_OF_XLOG_SHORT_PHD,
-};
+use postgres_ffi::{XLOG_SIZE_OF_XLOG_RECORD, XLOG_SIZE_OF_XLOG_SHORT_PHD};
 use std::path::{Path, PathBuf};
 use std::process::Command;
 use std::time::{Duration, Instant};
@@ -264,21 +262,11 @@ fn craft_internal<C: postgres::GenericClient>(
        intermediate_lsns.insert(0, initial_lsn);
    }

-    // Some records may be not flushed, e.g. non-transactional logical messages. Flush now.
+    // Some records may be not flushed, e.g. non-transactional logical messages.
    //
-    // If the previous WAL record ended exactly at page boundary, pg_current_wal_insert_lsn
-    // returns the position just after the page header on the next page. That's where the next
-    // record will be inserted. But the page header hasn't actually been written to the WAL
-    // yet, and if you try to flush it, you get a "request to flush past end of generated WAL"
-    // error. Because of that, if the insert location is just after a page header, back off to
-    // previous page boundary.
-    let mut lsn = u64::from(client.pg_current_wal_insert_lsn()?);
-    if lsn % WAL_SEGMENT_SIZE as u64 == XLOG_SIZE_OF_XLOG_LONG_PHD as u64 {
-        lsn -= XLOG_SIZE_OF_XLOG_LONG_PHD as u64;
-    } else if lsn % XLOG_BLCKSZ as u64 == XLOG_SIZE_OF_XLOG_SHORT_PHD as u64 {
-        lsn -= XLOG_SIZE_OF_XLOG_SHORT_PHD as u64;
-    }
-    client.execute("select neon_xlogflush($1)", &[&PgLsn::from(lsn)])?;
+    // Note: this is broken if pg_current_wal_insert_lsn is at page boundary
+    // because pg_current_wal_insert_lsn skips page headers.
+    client.execute("select neon_xlogflush(pg_current_wal_insert_lsn())", &[])?;
    Ok(intermediate_lsns)
 }

@@ -332,49 +320,38 @@ impl Crafter for LastWalRecordXlogSwitchEndsOnPageBoundary {

        client.execute("CREATE table t(x int)", &[])?;

-        // Add padding so the XLOG_SWITCH record ends exactly on XLOG_BLCKSZ boundary.  We
-        // will use carefully-sized logical messages to advance WAL insert location such
-        // that there is just enough space on the page for the XLOG_SWITCH record.
-        loop {
-            // We start with measuring how much WAL it takes for one logical message,
-            // considering all alignments and headers.
+        // Add padding so the XLOG_SWITCH record ends exactly on XLOG_BLCKSZ boundary.
+        // We will use logical message as the padding. We start with detecting how much WAL
+        // it takes for one logical message, considering all alignments and headers.
+        let base_wal_advance = {
            let before_lsn = client.pg_current_wal_insert_lsn()?;
+            // Small non-empty message bigger than few bytes is more likely than an empty
+            // message to have the same format as the big padding message.
            client.execute(
                "SELECT pg_logical_emit_message(false, 'swch', REPEAT('a', 10))",
                &[],
            )?;
-            let after_lsn = client.pg_current_wal_insert_lsn()?;
-
-            // Did the record cross a page boundary? If it did, start over. Crossing a
-            // page boundary adds to the apparent size of the record because of the page
-            // header, which throws off the calculation.
-            if u64::from(before_lsn) / XLOG_BLCKSZ as u64
-                != u64::from(after_lsn) / XLOG_BLCKSZ as u64
-            {
-                continue;
-            }
-            // base_size is the size of a logical message without the payload
-            let base_size = u64::from(after_lsn) - u64::from(before_lsn) - 10;
-
-            // Is there enough space on the page for another logical message and an
-            // XLOG_SWITCH? If not, start over.
-            let page_remain = XLOG_BLCKSZ as u64 - u64::from(after_lsn) % XLOG_BLCKSZ as u64;
-            if page_remain < base_size - XLOG_SIZE_OF_XLOG_RECORD as u64 {
-                continue;
-            }
-
-            // We will write another logical message, such that after the logical message
-            // record, there will be space for exactly one XLOG_SWITCH. How large should
-            // the logical message's payload be? An XLOG_SWITCH record has no data => its
-            // size is exactly XLOG_SIZE_OF_XLOG_RECORD.
-            let repeats = page_remain - base_size - XLOG_SIZE_OF_XLOG_RECORD as u64;
-
-            client.execute(
-                "SELECT pg_logical_emit_message(false, 'swch', REPEAT('a', $1))",
-                &[&(repeats as i32)],
-            )?;
-            break;
+            // The XLOG_SWITCH record has no data => its size is exactly XLOG_SIZE_OF_XLOG_RECORD.
+            (u64::from(client.pg_current_wal_insert_lsn()?) - u64::from(before_lsn)) as usize
+                + XLOG_SIZE_OF_XLOG_RECORD
+        };
+        let mut remaining_lsn =
+            XLOG_BLCKSZ - u64::from(client.pg_current_wal_insert_lsn()?) as usize % XLOG_BLCKSZ;
+        if remaining_lsn < base_wal_advance {
+            remaining_lsn += XLOG_BLCKSZ;
        }
+        let repeats = 10 + remaining_lsn - base_wal_advance;
+        info!(
+            "current_wal_insert_lsn={}, remaining_lsn={}, base_wal_advance={}, repeats={}",
+            client.pg_current_wal_insert_lsn()?,
+            remaining_lsn,
+            base_wal_advance,
+            repeats
+        );
+        client.execute(
+            "SELECT pg_logical_emit_message(false, 'swch', REPEAT('a', $1))",
+            &[&(repeats as i32)],
+        )?;
        info!(
            "current_wal_insert_lsn={}, XLOG_SIZE_OF_XLOG_RECORD={}",
            client.pg_current_wal_insert_lsn()?,
--- a/libs/remote_storage/src/lib.rs
+++ b/libs/remote_storage/src/lib.rs
@@ -21,13 +21,11 @@ use std::{
    fmt::Debug,
    num::{NonZeroU32, NonZeroUsize},
    pin::Pin,
-    str::FromStr,
    sync::Arc,
    time::{Duration, SystemTime},
 };

 use anyhow::{bail, Context};
-use aws_sdk_s3::types::StorageClass;
 use camino::{Utf8Path, Utf8PathBuf};

 use bytes::Bytes;
@@ -136,11 +134,6 @@ impl RemotePath {
    pub fn strip_prefix(&self, p: &RemotePath) -> Result<&Utf8Path, std::path::StripPrefixError> {
        self.0.strip_prefix(&p.0)
    }
-
-    pub fn add_trailing_slash(&self) -> Self {
-        // Unwrap safety inputs are guararnteed to be valid UTF-8
-        Self(format!("{}/", self.0).try_into().unwrap())
-    }
 }

 /// We don't need callers to be able to pass arbitrary delimiters: just control
@@ -164,21 +157,47 @@ pub struct Listing {
 /// providing basic CRUD operations for storage files.
 #[allow(async_fn_in_trait)]
 pub trait RemoteStorage: Send + Sync + 'static {
-    /// List objects in remote storage, with semantics matching AWS S3's ListObjectsV2.
-    /// (see `<https://docs.aws.amazon.com/AmazonS3/latest/API/API_ListObjectsV2.html>`)
-    ///
-    /// Note that the prefix is relative to any `prefix_in_bucket` configured for the client, not
-    /// from the absolute root of the bucket.
-    ///
-    /// `mode` configures whether to use a delimiter.  Without a delimiter all keys
-    /// within the prefix are listed in the `keys` of the result.  With a delimiter, any "directories" at the top level of
-    /// the prefix are returned in the `prefixes` of the result, and keys in the top level of the prefix are
-    /// returned in `keys` ().
-    ///
-    /// `max_keys` controls the maximum number of keys that will be returned.  If this is None, this function
-    /// will iteratively call listobjects until it runs out of keys.  Note that this is not safe to use on
-    /// unlimted size buckets, as the full list of objects is allocated into a monolithic data structure.
+    /// Lists all top level subdirectories for a given prefix
+    /// Note: here we assume that if the prefix is passed it was obtained via remote_object_id
+    /// which already takes into account any kind of global prefix (prefix_in_bucket for S3 or storage_root for LocalFS)
+    /// so this method doesnt need to.
+    async fn list_prefixes(
+        &self,
+        prefix: Option<&RemotePath>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        let result = self
+            .list(prefix, ListingMode::WithDelimiter, None, cancel)
+            .await?
+            .prefixes;
+        Ok(result)
+    }
+    /// Lists all files in directory "recursively"
+    /// (not really recursively, because AWS has a flat namespace)
+    /// Note: This is subtely different than list_prefixes,
+    /// because it is for listing files instead of listing
+    /// names sharing common prefixes.
+    /// For example,
+    /// list_files("foo/bar") = ["foo/bar/cat123.txt",
+    /// "foo/bar/cat567.txt", "foo/bar/dog123.txt", "foo/bar/dog456.txt"]
+    /// whereas,
+    /// list_prefixes("foo/bar/") = ["cat", "dog"]
+    /// See `test_real_s3.rs` for more details.
    ///
+    /// max_keys limits max number of keys returned; None means unlimited.
+    async fn list_files(
+        &self,
+        prefix: Option<&RemotePath>,
+        max_keys: Option<NonZeroU32>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        let result = self
+            .list(prefix, ListingMode::NoDelimiter, max_keys, cancel)
+            .await?
+            .keys;
+        Ok(result)
+    }
+
    async fn list(
        &self,
        prefix: Option<&RemotePath>,
@@ -317,6 +336,41 @@ impl<Other: RemoteStorage> GenericRemoteStorage<Arc<Other>> {
        }
    }

+    // A function for listing all the files in a "directory"
+    // Example:
+    // list_files("foo/bar") = ["foo/bar/a.txt", "foo/bar/b.txt"]
+    //
+    // max_keys limits max number of keys returned; None means unlimited.
+    pub async fn list_files(
+        &self,
+        folder: Option<&RemotePath>,
+        max_keys: Option<NonZeroU32>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        match self {
+            Self::LocalFs(s) => s.list_files(folder, max_keys, cancel).await,
+            Self::AwsS3(s) => s.list_files(folder, max_keys, cancel).await,
+            Self::AzureBlob(s) => s.list_files(folder, max_keys, cancel).await,
+            Self::Unreliable(s) => s.list_files(folder, max_keys, cancel).await,
+        }
+    }
+
+    // lists common *prefixes*, if any of files
+    // Example:
+    // list_prefixes("foo123","foo567","bar123","bar432") = ["foo", "bar"]
+    pub async fn list_prefixes(
+        &self,
+        prefix: Option<&RemotePath>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        match self {
+            Self::LocalFs(s) => s.list_prefixes(prefix, cancel).await,
+            Self::AwsS3(s) => s.list_prefixes(prefix, cancel).await,
+            Self::AzureBlob(s) => s.list_prefixes(prefix, cancel).await,
+            Self::Unreliable(s) => s.list_prefixes(prefix, cancel).await,
+        }
+    }
+
    /// See [`RemoteStorage::upload`]
    pub async fn upload(
        &self,
@@ -565,7 +619,6 @@ pub struct S3Config {
    /// See [`DEFAULT_REMOTE_STORAGE_S3_CONCURRENCY_LIMIT`] for more details.
    pub concurrency_limit: NonZeroUsize,
    pub max_keys_per_list_response: Option<i32>,
-    pub upload_storage_class: Option<StorageClass>,
 }

 impl Debug for S3Config {
@@ -694,18 +747,6 @@ impl RemoteStorageConfig {
                    endpoint,
                    concurrency_limit,
                    max_keys_per_list_response,
-                    upload_storage_class: toml
-                        .get("upload_storage_class")
-                        .map(|prefix_in_bucket| -> anyhow::Result<_> {
-                            let s = parse_toml_string("upload_storage_class", prefix_in_bucket)?;
-                            let storage_class = StorageClass::from_str(&s).expect("infallible");
-                            #[allow(deprecated)]
-                            if matches!(storage_class, StorageClass::Unknown(_)) {
-                                bail!("Specified storage class unknown to SDK: '{s}'. Allowed values: {:?}", StorageClass::values());
-                            }
-                            Ok(storage_class)
-                        })
-                        .transpose()?,
                })
            }
            (_, _, _, Some(_), None) => {
--- a/libs/remote_storage/src/local_fs.rs
+++ b/libs/remote_storage/src/local_fs.rs
@@ -5,9 +5,11 @@
 //! volume is mounted to the local FS.

 use std::{
-    collections::HashSet,
+    borrow::Cow,
+    future::Future,
    io::ErrorKind,
    num::NonZeroU32,
+    pin::Pin,
    time::{Duration, SystemTime, UNIX_EPOCH},
 };

@@ -20,11 +22,11 @@ use tokio::{
    io::{self, AsyncReadExt, AsyncSeekExt, AsyncWriteExt},
 };
 use tokio_util::{io::ReaderStream, sync::CancellationToken};
-use utils::crashsafe::path_with_suffix_extension;
+use tracing::*;
+use utils::{crashsafe::path_with_suffix_extension, fs_ext::is_directory_empty};

 use crate::{
    Download, DownloadError, Listing, ListingMode, RemotePath, TimeTravelError, TimeoutOrCancel,
-    REMOTE_STORAGE_PREFIX_SEPARATOR,
 };

 use super::{RemoteStorage, StorageMetadata};
@@ -91,47 +93,7 @@ impl LocalFs {

    #[cfg(test)]
    async fn list_all(&self) -> anyhow::Result<Vec<RemotePath>> {
-        use std::{future::Future, pin::Pin};
-        fn get_all_files<'a, P>(
-            directory_path: P,
-        ) -> Pin<Box<dyn Future<Output = anyhow::Result<Vec<Utf8PathBuf>>> + Send + Sync + 'a>>
-        where
-            P: AsRef<Utf8Path> + Send + Sync + 'a,
-        {
-            Box::pin(async move {
-                let directory_path = directory_path.as_ref();
-                if directory_path.exists() {
-                    if directory_path.is_dir() {
-                        let mut paths = Vec::new();
-                        let mut dir_contents = fs::read_dir(directory_path).await?;
-                        while let Some(dir_entry) = dir_contents.next_entry().await? {
-                            let file_type = dir_entry.file_type().await?;
-                            let entry_path =
-                                Utf8PathBuf::from_path_buf(dir_entry.path()).map_err(|pb| {
-                                    anyhow::Error::msg(format!(
-                                        "non-Unicode path: {}",
-                                        pb.to_string_lossy()
-                                    ))
-                                })?;
-                            if file_type.is_symlink() {
-                                tracing::debug!("{entry_path:?} is a symlink, skipping")
-                            } else if file_type.is_dir() {
-                                paths.extend(get_all_files(&entry_path).await?.into_iter())
-                            } else {
-                                paths.push(entry_path);
-                            }
-                        }
-                        Ok(paths)
-                    } else {
-                        bail!("Path {directory_path:?} is not a directory")
-                    }
-                } else {
-                    Ok(Vec::new())
-                }
-            })
-        }
-
-        Ok(get_all_files(&self.storage_root)
+        Ok(get_all_files(&self.storage_root, true)
            .await?
            .into_iter()
            .map(|path| {
@@ -158,14 +120,6 @@ impl LocalFs {
        // S3 object list prefixes can be arbitrary strings, but when reading
        // the local filesystem we need a directory to start calling read_dir on.
        let mut initial_dir = full_path.clone();
-
-        // If there's no trailing slash, we have to start looking from one above: even if
-        // `initial_dir` is a directory, we should still list any prefixes in the parent
-        // that start with the same string.
-        if !full_path.to_string().ends_with('/') {
-            initial_dir.pop();
-        }
-
        loop {
            // Did we make it to the root?
            if initial_dir.parent().is_none() {
@@ -341,66 +295,61 @@ impl RemoteStorage for LocalFs {
        let op = async {
            let mut result = Listing::default();

-            // Filter out directories: in S3 directories don't exist, only the keys within them do.
-            let keys = self
-                .list_recursive(prefix)
+            if let ListingMode::NoDelimiter = mode {
+                let keys = self
+                    .list_recursive(prefix)
+                    .await
+                    .map_err(DownloadError::Other)?;
+
+                result.keys = keys
+                    .into_iter()
+                    .filter(|k| {
+                        let path = k.with_base(&self.storage_root);
+                        !path.is_dir()
+                    })
+                    .collect();
+
+                if let Some(max_keys) = max_keys {
+                    result.keys.truncate(max_keys.get() as usize);
+                }
+
+                return Ok(result);
+            }
+
+            let path = match prefix {
+                Some(prefix) => Cow::Owned(prefix.with_base(&self.storage_root)),
+                None => Cow::Borrowed(&self.storage_root),
+            };
+
+            let prefixes_to_filter = get_all_files(path.as_ref(), false)
                .await
                .map_err(DownloadError::Other)?;
-            let keys = keys
-                .into_iter()
-                .filter(|k| {
-                    let path = k.with_base(&self.storage_root);
-                    !path.is_dir()
-                })
-                .collect();

-            if let ListingMode::NoDelimiter = mode {
-                result.keys = keys;
-            } else {
-                let mut prefixes = HashSet::new();
-                for key in keys {
-                    // If the part after the prefix includes a "/", take only the first part and put it in `prefixes`.
-                    let relative_key = if let Some(prefix) = prefix {
-                        let mut prefix = prefix.clone();
-                        // We only strip the dirname of the prefix, so that when we strip it from the start of keys we
-                        // end up with full file/dir names.
-                        let prefix_full_local_path = prefix.with_base(&self.storage_root);
-                        let has_slash = prefix.0.to_string().ends_with('/');
-                        let strip_prefix = if prefix_full_local_path.is_dir() && has_slash {
-                            prefix
-                        } else {
-                            prefix.0.pop();
-                            prefix
-                        };
-
-                        RemotePath::new(key.strip_prefix(&strip_prefix).unwrap()).unwrap()
-                    } else {
-                        key
-                    };
-
-                    let relative_key = format!("{}", relative_key);
-                    if relative_key.contains(REMOTE_STORAGE_PREFIX_SEPARATOR) {
-                        let first_part = relative_key
-                            .split(REMOTE_STORAGE_PREFIX_SEPARATOR)
-                            .next()
-                            .unwrap()
-                            .to_owned();
-                        prefixes.insert(first_part);
-                    } else {
-                        result
-                            .keys
-                            .push(RemotePath::from_string(&relative_key).unwrap());
-                    }
+            // filter out empty directories to mirror s3 behavior.
+            for prefix in prefixes_to_filter {
+                if prefix.is_dir()
+                    && is_directory_empty(&prefix)
+                        .await
+                        .map_err(DownloadError::Other)?
+                {
+                    continue;
+                }
+
+                let stripped = prefix
+                    .strip_prefix(&self.storage_root)
+                    .context("Failed to strip prefix")
+                    .and_then(RemotePath::new)
+                    .expect(
+                        "We list files for storage root, hence should be able to remote the prefix",
+                    );
+
+                if prefix.is_dir() {
+                    result.prefixes.push(stripped);
+                } else {
+                    result.keys.push(stripped);
                }
-                result.prefixes = prefixes
-                    .into_iter()
-                    .map(|s| RemotePath::from_string(&s).unwrap())
-                    .collect();
            }

-            if let Some(max_keys) = max_keys {
-                result.keys.truncate(max_keys.get() as usize);
-            }
            Ok(result)
        };

@@ -611,6 +560,50 @@ fn storage_metadata_path(original_path: &Utf8Path) -> Utf8PathBuf {
    path_with_suffix_extension(original_path, "metadata")
 }

+fn get_all_files<'a, P>(
+    directory_path: P,
+    recursive: bool,
+) -> Pin<Box<dyn Future<Output = anyhow::Result<Vec<Utf8PathBuf>>> + Send + Sync + 'a>>
+where
+    P: AsRef<Utf8Path> + Send + Sync + 'a,
+{
+    Box::pin(async move {
+        let directory_path = directory_path.as_ref();
+        if directory_path.exists() {
+            if directory_path.is_dir() {
+                let mut paths = Vec::new();
+                let mut dir_contents = fs::read_dir(directory_path).await?;
+                while let Some(dir_entry) = dir_contents.next_entry().await? {
+                    let file_type = dir_entry.file_type().await?;
+                    let entry_path =
+                        Utf8PathBuf::from_path_buf(dir_entry.path()).map_err(|pb| {
+                            anyhow::Error::msg(format!(
+                                "non-Unicode path: {}",
+                                pb.to_string_lossy()
+                            ))
+                        })?;
+                    if file_type.is_symlink() {
+                        debug!("{entry_path:?} is a symlink, skipping")
+                    } else if file_type.is_dir() {
+                        if recursive {
+                            paths.extend(get_all_files(&entry_path, true).await?.into_iter())
+                        } else {
+                            paths.push(entry_path)
+                        }
+                    } else {
+                        paths.push(entry_path);
+                    }
+                }
+                Ok(paths)
+            } else {
+                bail!("Path {directory_path:?} is not a directory")
+            }
+        } else {
+            Ok(Vec::new())
+        }
+    })
+}
+
 async fn create_target_directory(target_file_path: &Utf8Path) -> anyhow::Result<()> {
    let target_dir = match target_file_path.parent() {
        Some(parent_dir) => parent_dir,
@@ -930,18 +923,13 @@ mod fs_tests {
        // No delimiter: should recursively list everything
        let (storage, cancel) = create_storage()?;
        let child = upload_dummy_file(&storage, "grandparent/parent/child", None, &cancel).await?;
-        let child_sibling =
-            upload_dummy_file(&storage, "grandparent/parent/child_sibling", None, &cancel).await?;
        let uncle = upload_dummy_file(&storage, "grandparent/uncle", None, &cancel).await?;

        let listing = storage
            .list(None, ListingMode::NoDelimiter, None, &cancel)
            .await?;
        assert!(listing.prefixes.is_empty());
-        assert_eq!(
-            listing.keys.into_iter().collect::<HashSet<_>>(),
-            HashSet::from([uncle.clone(), child.clone(), child_sibling.clone()])
-        );
+        assert_eq!(listing.keys, [uncle.clone(), child.clone()].to_vec());

        // Delimiter: should only go one deep
        let listing = storage
@@ -954,25 +942,7 @@ mod fs_tests {
        );
        assert!(listing.keys.is_empty());

-        // Delimiter & prefix with a trailing slash
-        let listing = storage
-            .list(
-                Some(&RemotePath::from_string("timelines/some_timeline/grandparent/").unwrap()),
-                ListingMode::WithDelimiter,
-                None,
-                &cancel,
-            )
-            .await?;
-        assert_eq!(
-            listing.keys,
-            [RemotePath::from_string("uncle").unwrap()].to_vec()
-        );
-        assert_eq!(
-            listing.prefixes,
-            [RemotePath::from_string("parent").unwrap()].to_vec()
-        );
-
-        // Delimiter and prefix without a trailing slash
+        // Delimiter & prefix
        let listing = storage
            .list(
                Some(&RemotePath::from_string("timelines/some_timeline/grandparent").unwrap()),
@@ -981,66 +951,12 @@ mod fs_tests {
                &cancel,
            )
            .await?;
-        assert_eq!(listing.keys, [].to_vec());
        assert_eq!(
            listing.prefixes,
-            [RemotePath::from_string("grandparent").unwrap()].to_vec()
-        );
-
-        // Delimiter and prefix that's partway through a path component
-        let listing = storage
-            .list(
-                Some(&RemotePath::from_string("timelines/some_timeline/grandp").unwrap()),
-                ListingMode::WithDelimiter,
-                None,
-                &cancel,
-            )
-            .await?;
-        assert_eq!(listing.keys, [].to_vec());
-        assert_eq!(
-            listing.prefixes,
-            [RemotePath::from_string("grandparent").unwrap()].to_vec()
-        );
-
-        Ok(())
-    }
-
-    #[tokio::test]
-    async fn list_part_component() -> anyhow::Result<()> {
-        // No delimiter: should recursively list everything
-        let (storage, cancel) = create_storage()?;
-
-        // Imitates what happens in a tenant path when we have an unsharded path and a sharded path, and do a listing
-        // of the unsharded path: although there is a "directory" at the unsharded path, it should be handled as
-        // a freeform prefix.
-        let _child_a =
-            upload_dummy_file(&storage, "grandparent/tenant-01/child", None, &cancel).await?;
-        let _child_b =
-            upload_dummy_file(&storage, "grandparent/tenant/child", None, &cancel).await?;
-
-        // Delimiter and prefix that's partway through a path component
-        let listing = storage
-            .list(
-                Some(
-                    &RemotePath::from_string("timelines/some_timeline/grandparent/tenant").unwrap(),
-                ),
-                ListingMode::WithDelimiter,
-                None,
-                &cancel,
-            )
-            .await?;
-        assert_eq!(listing.keys, [].to_vec());
-
-        let mut found_prefixes = listing.prefixes.clone();
-        found_prefixes.sort();
-        assert_eq!(
-            found_prefixes,
-            [
-                RemotePath::from_string("tenant").unwrap(),
-                RemotePath::from_string("tenant-01").unwrap(),
-            ]
-            .to_vec()
+            [RemotePath::from_string("timelines/some_timeline/grandparent/parent").unwrap()]
+                .to_vec()
        );
+        assert_eq!(listing.keys, [uncle.clone()].to_vec());

        Ok(())
    }
--- a/libs/remote_storage/src/s3_bucket.rs
+++ b/libs/remote_storage/src/s3_bucket.rs
@@ -30,7 +30,7 @@ use aws_sdk_s3::{
    config::{AsyncSleep, Builder, IdentityCache, Region, SharedAsyncSleep},
    error::SdkError,
    operation::get_object::GetObjectError,
-    types::{Delete, DeleteMarkerEntry, ObjectIdentifier, ObjectVersion, StorageClass},
+    types::{Delete, DeleteMarkerEntry, ObjectIdentifier, ObjectVersion},
    Client,
 };
 use aws_smithy_async::rt::sleep::TokioSleep;
@@ -62,7 +62,6 @@ pub struct S3Bucket {
    bucket_name: String,
    prefix_in_bucket: Option<String>,
    max_keys_per_list_response: Option<i32>,
-    upload_storage_class: Option<StorageClass>,
    concurrency_limiter: ConcurrencyLimiter,
    // Per-request timeout. Accessible for tests.
    pub timeout: Duration,
@@ -155,7 +154,6 @@ impl S3Bucket {
            max_keys_per_list_response: aws_config.max_keys_per_list_response,
            prefix_in_bucket,
            concurrency_limiter: ConcurrencyLimiter::new(aws_config.concurrency_limit.get()),
-            upload_storage_class: aws_config.upload_storage_class.clone(),
            timeout,
        })
    }
@@ -180,7 +178,10 @@ impl S3Bucket {

    pub fn relative_path_to_s3_object(&self, path: &RemotePath) -> String {
        assert_eq!(std::path::MAIN_SEPARATOR, REMOTE_STORAGE_PREFIX_SEPARATOR);
-        let path_string = path.get_path().as_str();
+        let path_string = path
+            .get_path()
+            .as_str()
+            .trim_end_matches(REMOTE_STORAGE_PREFIX_SEPARATOR);
        match &self.prefix_in_bucket {
            Some(prefix) => prefix.clone() + "/" + path_string,
            None => path_string.to_string(),
@@ -470,11 +471,16 @@ impl RemoteStorage for S3Bucket {
        // get the passed prefix or if it is not set use prefix_in_bucket value
        let list_prefix = prefix
            .map(|p| self.relative_path_to_s3_object(p))
-            .or_else(|| {
-                self.prefix_in_bucket.clone().map(|mut s| {
-                    s.push(REMOTE_STORAGE_PREFIX_SEPARATOR);
-                    s
-                })
+            .or_else(|| self.prefix_in_bucket.clone())
+            .map(|mut p| {
+                // required to end with a separator
+                // otherwise request will return only the entry of a prefix
+                if matches!(mode, ListingMode::WithDelimiter)
+                    && !p.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR)
+                {
+                    p.push(REMOTE_STORAGE_PREFIX_SEPARATOR);
+                }
+                p
            });

        let _permit = self.permit(kind, cancel).await?;
@@ -543,15 +549,11 @@ impl RemoteStorage for S3Bucket {
                }
            }

-            // S3 gives us prefixes like "foo/", we return them like "foo"
-            result.prefixes.extend(prefixes.iter().filter_map(|o| {
-                Some(
-                    self.s3_object_to_relative_path(
-                        o.prefix()?
-                            .trim_end_matches(REMOTE_STORAGE_PREFIX_SEPARATOR),
-                    ),
-                )
-            }));
+            result.prefixes.extend(
+                prefixes
+                    .iter()
+                    .filter_map(|o| Some(self.s3_object_to_relative_path(o.prefix()?))),
+            );

            continuation_token = match response.next_continuation_token {
                Some(new_token) => Some(new_token),
@@ -584,7 +586,6 @@ impl RemoteStorage for S3Bucket {
            .bucket(self.bucket_name.clone())
            .key(self.relative_path_to_s3_object(to))
            .set_metadata(metadata.map(|m| m.0))
-            .set_storage_class(self.upload_storage_class.clone())
            .content_length(from_size_bytes.try_into()?)
            .body(bytes_stream)
            .send();
@@ -636,7 +637,6 @@ impl RemoteStorage for S3Bucket {
            .copy_object()
            .bucket(self.bucket_name.clone())
            .key(self.relative_path_to_s3_object(to))
-            .set_storage_class(self.upload_storage_class.clone())
            .copy_source(copy_source)
            .send();

@@ -894,7 +894,6 @@ impl RemoteStorage for S3Bucket {
                                    .copy_object()
                                    .bucket(self.bucket_name.clone())
                                    .key(key)
-                                    .set_storage_class(self.upload_storage_class.clone())
                                    .copy_source(&source_id)
                                    .send();

@@ -1051,22 +1050,22 @@ mod tests {
            Some("/test/prefix/"),
        ];
        let expected_outputs = [
-            vec!["", "some/path", "some/path/"],
-            vec!["/", "/some/path", "/some/path/"],
+            vec!["", "some/path", "some/path"],
+            vec!["/", "/some/path", "/some/path"],
            vec![
                "test/prefix/",
                "test/prefix/some/path",
-                "test/prefix/some/path/",
+                "test/prefix/some/path",
            ],
            vec![
                "test/prefix/",
                "test/prefix/some/path",
-                "test/prefix/some/path/",
+                "test/prefix/some/path",
            ],
            vec![
                "test/prefix/",
                "test/prefix/some/path",
-                "test/prefix/some/path/",
+                "test/prefix/some/path",
            ],
        ];

@@ -1078,7 +1077,6 @@ mod tests {
                endpoint: None,
                concurrency_limit: NonZeroUsize::new(100).unwrap(),
                max_keys_per_list_response: Some(5),
-                upload_storage_class: None,
            };
            let storage =
                S3Bucket::new(&config, std::time::Duration::ZERO).expect("remote storage init");
--- a/libs/remote_storage/src/simulate_failures.rs
+++ b/libs/remote_storage/src/simulate_failures.rs
@@ -107,6 +107,27 @@ impl UnreliableWrapper {
 type VoidStorage = crate::LocalFs;

 impl RemoteStorage for UnreliableWrapper {
+    async fn list_prefixes(
+        &self,
+        prefix: Option<&RemotePath>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        self.attempt(RemoteOp::ListPrefixes(prefix.cloned()))
+            .map_err(DownloadError::Other)?;
+        self.inner.list_prefixes(prefix, cancel).await
+    }
+
+    async fn list_files(
+        &self,
+        folder: Option<&RemotePath>,
+        max_keys: Option<NonZeroU32>,
+        cancel: &CancellationToken,
+    ) -> Result<Vec<RemotePath>, DownloadError> {
+        self.attempt(RemoteOp::ListPrefixes(folder.cloned()))
+            .map_err(DownloadError::Other)?;
+        self.inner.list_files(folder, max_keys, cancel).await
+    }
+
    async fn list(
        &self,
        prefix: Option<&RemotePath>,
--- a/libs/remote_storage/tests/common/tests.rs
+++ b/libs/remote_storage/tests/common/tests.rs
@@ -1,6 +1,5 @@
 use anyhow::Context;
 use camino::Utf8Path;
-use remote_storage::ListingMode;
 use remote_storage::RemotePath;
 use std::sync::Arc;
 use std::{collections::HashSet, num::NonZeroU32};
@@ -55,9 +54,9 @@ async fn pagination_should_work(ctx: &mut MaybeEnabledStorageWithTestBlobs) -> a
    let base_prefix = RemotePath::new(Utf8Path::new(ctx.enabled.base_prefix))
        .context("common_prefix construction")?;
    let root_remote_prefixes = test_client
-        .list(None, ListingMode::WithDelimiter, None, &cancel)
-        .await?
-        .prefixes
+        .list_prefixes(None, &cancel)
+        .await
+        .context("client list root prefixes failure")?
        .into_iter()
        .collect::<HashSet<_>>();
    assert_eq!(
@@ -66,14 +65,9 @@ async fn pagination_should_work(ctx: &mut MaybeEnabledStorageWithTestBlobs) -> a
    );

    let nested_remote_prefixes = test_client
-        .list(
-            Some(&base_prefix.add_trailing_slash()),
-            ListingMode::WithDelimiter,
-            None,
-            &cancel,
-        )
-        .await?
-        .prefixes
+        .list_prefixes(Some(&base_prefix), &cancel)
+        .await
+        .context("client list nested prefixes failure")?
        .into_iter()
        .collect::<HashSet<_>>();
    let remote_only_prefixes = nested_remote_prefixes
@@ -96,13 +90,11 @@ async fn pagination_should_work(ctx: &mut MaybeEnabledStorageWithTestBlobs) -> a
 ///
 /// First, create a set of S3 objects with keys `random_prefix/folder{j}/blob_{i}.txt` in [`upload_remote_data`]
 /// Then performs the following queries:
-///    1. `list(None)`. This should return all files `random_prefix/folder{j}/blob_{i}.txt`
-///    2. `list("folder1")`.  This  should return all files `random_prefix/folder1/blob_{i}.txt`
+///    1. `list_files(None)`. This should return all files `random_prefix/folder{j}/blob_{i}.txt`
+///    2. `list_files("folder1")`.  This  should return all files `random_prefix/folder1/blob_{i}.txt`
 #[test_context(MaybeEnabledStorageWithSimpleTestBlobs)]
 #[tokio::test]
-async fn list_no_delimiter_works(
-    ctx: &mut MaybeEnabledStorageWithSimpleTestBlobs,
-) -> anyhow::Result<()> {
+async fn list_files_works(ctx: &mut MaybeEnabledStorageWithSimpleTestBlobs) -> anyhow::Result<()> {
    let ctx = match ctx {
        MaybeEnabledStorageWithSimpleTestBlobs::Enabled(ctx) => ctx,
        MaybeEnabledStorageWithSimpleTestBlobs::Disabled => return Ok(()),
@@ -115,36 +107,29 @@ async fn list_no_delimiter_works(
    let base_prefix =
        RemotePath::new(Utf8Path::new("folder1")).context("common_prefix construction")?;
    let root_files = test_client
-        .list(None, ListingMode::NoDelimiter, None, &cancel)
+        .list_files(None, None, &cancel)
        .await
        .context("client list root files failure")?
-        .keys
        .into_iter()
        .collect::<HashSet<_>>();
    assert_eq!(
        root_files,
        ctx.remote_blobs.clone(),
-        "remote storage list on root mismatches with the uploads."
+        "remote storage list_files on root mismatches with the uploads."
    );

    // Test that max_keys limit works. In total there are about 21 files (see
    // upload_simple_remote_data call in test_real_s3.rs).
    let limited_root_files = test_client
-        .list(
-            None,
-            ListingMode::NoDelimiter,
-            Some(NonZeroU32::new(2).unwrap()),
-            &cancel,
-        )
+        .list_files(None, Some(NonZeroU32::new(2).unwrap()), &cancel)
        .await
        .context("client list root files failure")?;
-    assert_eq!(limited_root_files.keys.len(), 2);
+    assert_eq!(limited_root_files.len(), 2);

    let nested_remote_files = test_client
-        .list(Some(&base_prefix), ListingMode::NoDelimiter, None, &cancel)
+        .list_files(Some(&base_prefix), None, &cancel)
        .await
        .context("client list nested files failure")?
-        .keys
        .into_iter()
        .collect::<HashSet<_>>();
    let trim_remote_blobs: HashSet<_> = ctx
@@ -156,7 +141,7 @@ async fn list_no_delimiter_works(
        .collect();
    assert_eq!(
        nested_remote_files, trim_remote_blobs,
-        "remote storage list on subdirrectory mismatches with the uploads."
+        "remote storage list_files on subdirrectory mismatches with the uploads."
    );
    Ok(())
 }
@@ -214,11 +199,7 @@ async fn delete_objects_works(ctx: &mut MaybeEnabledStorage) -> anyhow::Result<(

    ctx.client.delete_objects(&[path1, path2], &cancel).await?;

-    let prefixes = ctx
-        .client
-        .list(None, ListingMode::WithDelimiter, None, &cancel)
-        .await?
-        .prefixes;
+    let prefixes = ctx.client.list_prefixes(None, &cancel).await?;

    assert_eq!(prefixes.len(), 1);

--- a/libs/remote_storage/tests/test_real_azure.rs
+++ b/libs/remote_storage/tests/test_real_azure.rs
@@ -132,6 +132,10 @@ impl AsyncTestContext for MaybeEnabledStorageWithTestBlobs {
    }
 }

+// NOTE: the setups for the list_prefixes test and the list_files test are very similar
+// However, they are not idential. The list_prefixes function is concerned with listing prefixes,
+// whereas the list_files function is concerned with listing files.
+// See `RemoteStorage::list_files` documentation for more details
 enum MaybeEnabledStorageWithSimpleTestBlobs {
    Enabled(AzureWithSimpleTestBlobs),
    Disabled,
--- a/libs/remote_storage/tests/test_real_s3.rs
+++ b/libs/remote_storage/tests/test_real_s3.rs
@@ -12,8 +12,8 @@ use anyhow::Context;
 use camino::Utf8Path;
 use futures_util::StreamExt;
 use remote_storage::{
-    DownloadError, GenericRemoteStorage, ListingMode, RemotePath, RemoteStorageConfig,
-    RemoteStorageKind, S3Config,
+    DownloadError, GenericRemoteStorage, RemotePath, RemoteStorageConfig, RemoteStorageKind,
+    S3Config,
 };
 use test_context::test_context;
 use test_context::AsyncTestContext;
@@ -75,14 +75,11 @@ async fn s3_time_travel_recovery_works(ctx: &mut MaybeEnabledStorage) -> anyhow:
        client: &Arc<GenericRemoteStorage>,
        cancel: &CancellationToken,
    ) -> anyhow::Result<HashSet<RemotePath>> {
-        Ok(
-            retry(|| client.list(None, ListingMode::NoDelimiter, None, cancel))
-                .await
-                .context("list root files failure")?
-                .keys
-                .into_iter()
-                .collect::<HashSet<_>>(),
-        )
+        Ok(retry(|| client.list_files(None, None, cancel))
+            .await
+            .context("list root files failure")?
+            .into_iter()
+            .collect::<HashSet<_>>())
    }

    let cancel = CancellationToken::new();
@@ -297,6 +294,10 @@ impl AsyncTestContext for MaybeEnabledStorageWithTestBlobs {
    }
 }

+// NOTE: the setups for the list_prefixes test and the list_files test are very similar
+// However, they are not idential. The list_prefixes function is concerned with listing prefixes,
+// whereas the list_files function is concerned with listing files.
+// See `RemoteStorage::list_files` documentation for more details
 enum MaybeEnabledStorageWithSimpleTestBlobs {
    Enabled(S3WithSimpleTestBlobs),
    Disabled,
@@ -380,7 +381,6 @@ fn create_s3_client(
            endpoint: None,
            concurrency_limit: NonZeroUsize::new(100).unwrap(),
            max_keys_per_list_response,
-            upload_storage_class: None,
        }),
        timeout: RemoteStorageConfig::DEFAULT_TIMEOUT,
    };
--- a/libs/utils/src/generation.rs
+++ b/libs/utils/src/generation.rs
@@ -34,8 +34,6 @@ pub enum Generation {
 /// scenarios where pageservers might otherwise issue conflicting writes to
 /// remote storage
 impl Generation {
-    pub const MAX: Self = Self::Valid(u32::MAX);
-
    /// Create a new Generation that represents a legacy key format with
    /// no generation suffix
    pub fn none() -> Self {
--- a/pageserver/Cargo.toml
+++ b/pageserver/Cargo.toml
@@ -70,7 +70,6 @@ tokio-stream.workspace = true
 tokio-util.workspace = true
 toml_edit = { workspace = true, features = [ "serde" ] }
 tracing.workspace = true
-twox-hash.workspace = true
 url.workspace = true
 walkdir.workspace = true
 metrics.workspace = true
--- a/pageserver/client/src/mgmt_api.rs
+++ b/pageserver/client/src/mgmt_api.rs
@@ -243,19 +243,6 @@ impl Client {
        Ok(())
    }

-    pub async fn tenant_scan_remote_storage(
-        &self,
-        tenant_id: TenantId,
-    ) -> Result<TenantScanRemoteStorageResponse> {
-        let uri = format!(
-            "{}/v1/tenant/{tenant_id}/scan_remote_storage",
-            self.mgmt_api_endpoint
-        );
-        let response = self.request(Method::GET, &uri, ()).await?;
-        let body = response.json().await.map_err(Error::ReceiveBody)?;
-        Ok(body)
-    }
-
    pub async fn tenant_config(&self, req: &TenantConfigRequest) -> Result<()> {
        let uri = format!("{}/v1/tenant/config", self.mgmt_api_endpoint);
        self.request(Method::PUT, &uri, req).await?;
@@ -292,7 +279,7 @@ impl Client {
        lazy: bool,
    ) -> Result<()> {
        let req_body = TenantLocationConfigRequest {
-            tenant_id: None,
+            tenant_id: Some(tenant_shard_id),
            config,
        };

--- a/pageserver/client/src/page_service.rs
+++ b/pageserver/client/src/page_service.rs
@@ -60,7 +60,7 @@ impl Client {
    ) -> anyhow::Result<PagestreamClient> {
        let copy_both: tokio_postgres::CopyBothDuplex<bytes::Bytes> = self
            .client
-            .copy_both_simple(&format!("pagestream_v2 {tenant_id} {timeline_id}"))
+            .copy_both_simple(&format!("pagestream {tenant_id} {timeline_id}"))
            .await?;
        let Client {
            cancel_on_client_drop,
--- a/pageserver/compaction/src/compact_tiered.rs
+++ b/pageserver/compaction/src/compact_tiered.rs
@@ -18,7 +18,6 @@
 //! database size. For example, if the logical database size is 10 GB, we would
 //! generate new image layers every 10 GB of WAL.
 use futures::StreamExt;
-use pageserver_api::shard::ShardIdentity;
 use tracing::{debug, info};

 use std::collections::{HashSet, VecDeque};
@@ -126,7 +125,6 @@ async fn compact_level<E: CompactionJobExecutor>(
    }

    let mut state = LevelCompactionState {
-        shard_identity: *executor.get_shard_identity(),
        target_file_size,
        _lsn_range: lsn_range.clone(),
        layers: layer_fragments,
@@ -166,8 +164,6 @@ struct LevelCompactionState<'a, E>
 where
    E: CompactionJobExecutor,
 {
-    shard_identity: ShardIdentity,
-
    // parameters
    target_file_size: u64,

@@ -370,7 +366,6 @@ where
                .executor
                .get_keyspace(&job.key_range, job.lsn_range.end, ctx)
                .await?,
-            &self.shard_identity,
        ) * 8192;

        let wal_size = job
@@ -435,7 +430,7 @@ where
            keyspace,
            self.target_file_size / 8192,
        );
-        while let Some(key_range) = window.choose_next_image(&self.shard_identity) {
+        while let Some(key_range) = window.choose_next_image() {
            new_jobs.push(CompactionJob::<E> {
                key_range,
                lsn_range: job.lsn_range.clone(),
@@ -628,12 +623,7 @@ impl<K: CompactionKey> KeyspaceWindowPos<K> {
    }

    // Advance the cursor until it reaches 'target_keysize'.
-    fn advance_until_size(
-        &mut self,
-        w: &KeyspaceWindowHead<K>,
-        max_size: u64,
-        shard_identity: &ShardIdentity,
-    ) {
+    fn advance_until_size(&mut self, w: &KeyspaceWindowHead<K>, max_size: u64) {
        while self.accum_keysize < max_size && !self.reached_end(w) {
            let curr_range = &w.keyspace[self.keyspace_idx];
            if self.end_key < curr_range.start {
@@ -642,7 +632,7 @@ impl<K: CompactionKey> KeyspaceWindowPos<K> {
            }

            // We're now within 'curr_range'. Can we advance past it completely?
-            let distance = K::key_range_size(&(self.end_key..curr_range.end), shard_identity);
+            let distance = K::key_range_size(&(self.end_key..curr_range.end));
            if (self.accum_keysize + distance as u64) < max_size {
                // oh yeah, it fits
                self.end_key = curr_range.end;
@@ -651,7 +641,7 @@ impl<K: CompactionKey> KeyspaceWindowPos<K> {
            } else {
                // advance within the range
                let skip_key = self.end_key.skip_some();
-                let distance = K::key_range_size(&(self.end_key..skip_key), shard_identity);
+                let distance = K::key_range_size(&(self.end_key..skip_key));
                if (self.accum_keysize + distance as u64) < max_size {
                    self.end_key = skip_key;
                    self.accum_keysize += distance as u64;
@@ -687,7 +677,7 @@ where
        }
    }

-    fn choose_next_image(&mut self, shard_identity: &ShardIdentity) -> Option<Range<K>> {
+    fn choose_next_image(&mut self) -> Option<Range<K>> {
        if self.start_pos.keyspace_idx == self.head.keyspace.len() {
            // we've reached the end
            return None;
@@ -697,7 +687,6 @@ where
        next_pos.advance_until_size(
            &self.head,
            self.start_pos.accum_keysize + self.head.target_keysize,
-            shard_identity,
        );

        // See if we can gobble up the rest of the keyspace if we stretch out the layer, up to
@@ -706,7 +695,6 @@ where
        end_pos.advance_until_size(
            &self.head,
            self.start_pos.accum_keysize + (self.head.target_keysize * 5 / 4),
-            shard_identity,
        );
        if end_pos.reached_end(&self.head) {
            // gobble up any unused keyspace between the last used key and end of the range
--- a/pageserver/compaction/src/helpers.rs
+++ b/pageserver/compaction/src/helpers.rs
@@ -5,7 +5,6 @@ use crate::interface::*;
 use futures::future::BoxFuture;
 use futures::{Stream, StreamExt};
 use itertools::Itertools;
-use pageserver_api::shard::ShardIdentity;
 use pin_project_lite::pin_project;
 use std::collections::BinaryHeap;
 use std::collections::VecDeque;
@@ -14,17 +13,11 @@ use std::ops::{DerefMut, Range};
 use std::pin::Pin;
 use std::task::{ready, Poll};

-pub fn keyspace_total_size<K>(
-    keyspace: &CompactionKeySpace<K>,
-    shard_identity: &ShardIdentity,
-) -> u64
+pub fn keyspace_total_size<K>(keyspace: &CompactionKeySpace<K>) -> u64
 where
    K: CompactionKey,
 {
-    keyspace
-        .iter()
-        .map(|r| K::key_range_size(r, shard_identity) as u64)
-        .sum()
+    keyspace.iter().map(|r| K::key_range_size(r) as u64).sum()
 }

 pub fn overlaps_with<T: Ord>(a: &Range<T>, b: &Range<T>) -> bool {
--- a/pageserver/compaction/src/interface.rs
+++ b/pageserver/compaction/src/interface.rs
@@ -4,7 +4,7 @@
 //! All the heavy lifting is done by the create_image and create_delta
 //! functions that the implementor provides.
 use futures::Future;
-use pageserver_api::{key::Key, keyspace::ShardedRange, shard::ShardIdentity};
+use pageserver_api::{key::Key, keyspace::key_range_size};
 use std::ops::Range;
 use utils::lsn::Lsn;

@@ -32,8 +32,6 @@ pub trait CompactionJobExecutor {
    // Functions that the planner uses to support its decisions
    // ----

-    fn get_shard_identity(&self) -> &ShardIdentity;
-
    /// Return all layers that overlap the given bounding box.
    fn get_layers(
        &mut self,
@@ -100,7 +98,7 @@ pub trait CompactionKey: std::cmp::Ord + Clone + Copy + std::fmt::Display {
    ///
    /// This returns u32, for compatibility with Repository::key. If the
    /// distance is larger, return u32::MAX.
-    fn key_range_size(key_range: &Range<Self>, shard_identity: &ShardIdentity) -> u32;
+    fn key_range_size(key_range: &Range<Self>) -> u32;

    // return "self + 1"
    fn next(&self) -> Self;
@@ -115,8 +113,8 @@ impl CompactionKey for Key {
    const MIN: Self = Self::MIN;
    const MAX: Self = Self::MAX;

-    fn key_range_size(r: &std::ops::Range<Self>, shard_identity: &ShardIdentity) -> u32 {
-        ShardedRange::new(r.clone(), shard_identity).page_count()
+    fn key_range_size(r: &std::ops::Range<Self>) -> u32 {
+        key_range_size(r)
    }
    fn next(&self) -> Key {
        (self as &Key).next()
--- a/pageserver/compaction/src/simulator.rs
+++ b/pageserver/compaction/src/simulator.rs
@@ -3,7 +3,6 @@ mod draw;
 use draw::{LayerTraceEvent, LayerTraceFile, LayerTraceOp};

 use futures::StreamExt;
-use pageserver_api::shard::ShardIdentity;
 use rand::Rng;
 use tracing::info;

@@ -72,7 +71,7 @@ impl interface::CompactionKey for Key {
    const MIN: Self = u64::MIN;
    const MAX: Self = u64::MAX;

-    fn key_range_size(key_range: &Range<Self>, _shard_identity: &ShardIdentity) -> u32 {
+    fn key_range_size(key_range: &Range<Self>) -> u32 {
        std::cmp::min(key_range.end - key_range.start, u32::MAX as u64) as u32
    }

@@ -435,11 +434,6 @@ impl interface::CompactionJobExecutor for MockTimeline {
    type ImageLayer = Arc<MockImageLayer>;
    type RequestContext = MockRequestContext;

-    fn get_shard_identity(&self) -> &ShardIdentity {
-        static IDENTITY: ShardIdentity = ShardIdentity::unsharded();
-        &IDENTITY
-    }
-
    async fn get_layers(
        &mut self,
        key_range: &Range<Self::Key>,
--- a/pageserver/ctl/src/draw_timeline_dir.rs
+++ b/pageserver/ctl/src/draw_timeline_dir.rs
@@ -9,45 +9,18 @@
 //! Coordinates in both axis are compressed for better readability.
 //! (see <https://medium.com/algorithms-digest/coordinate-compression-2fff95326fb>)
 //!
-//! The plain text API was chosen so that we can easily work with filenames from various
-//! sources; see the Usage section below for examples.
-//!
-//! # Usage
-//!
-//! ## Producing the SVG
-//!
+//! Example use:
 //! ```bash
-//!
-//! # local timeline dir
-//! ls test_output/test_pgbench\[neon-45-684\]/repo/tenants/$TENANT/timelines/$TIMELINE | \
-//!     grep "__" | cargo run --release --bin pagectl draw-timeline-dir > out.svg
-//!
-//! # Layer map dump from `/v1/tenant/$TENANT/timeline/$TIMELINE/layer`
-//! (jq -r '.historic_layers[] | .layer_file_name' | cargo  run -p pagectl draw-timeline) < layer-map.json > out.svg
-//!
-//! # From an `index_part.json` in S3
-//! (jq -r '.layer_metadata | keys[]' | cargo  run -p pagectl draw-timeline ) < index_part.json-00000016 > out.svg
-//!
+//! $ ls test_output/test_pgbench\[neon-45-684\]/repo/tenants/$TENANT/timelines/$TIMELINE | \
+//! $   grep "__" | cargo run --release --bin pagectl draw-timeline-dir > out.svg
+//! $ firefox out.svg
 //! ```
 //!
-//! ## Viewing
+//! This API was chosen so that we can easily work with filenames extracted from ssh,
+//! or from pageserver log files.
 //!
-//! **Inkscape** is better than the built-in viewers in browsers.
-//!
-//! After selecting a layer file rectangle, use "Open XML Editor" (Ctrl|Cmd + Shift + X)
-//! to see the layer file name in the comment field.
-//!
-//! ```bash
-//!
-//! # Linux
-//! inkscape out.svg
-//!
-//! # macOS
-//! /Applications/Inkscape.app/Contents/MacOS/inkscape out.svg
-//!
-//! ```
-//!
-
+//! TODO Consider shipping this as a grafana panel plugin:
+//!      <https://grafana.com/tutorials/build-a-panel-plugin/>
 use anyhow::Result;
 use pageserver::repository::Key;
 use pageserver::METADATA_FILE_NAME;
@@ -92,12 +65,7 @@ fn parse_filename(name: &str) -> (Range<Key>, Range<Lsn>) {

 pub fn main() -> Result<()> {
    // Parse layer filenames from stdin
-    struct Layer {
-        filename: String,
-        key_range: Range<Key>,
-        lsn_range: Range<Lsn>,
-    }
-    let mut files: Vec<Layer> = vec![];
+    let mut ranges: Vec<(Range<Key>, Range<Lsn>)> = vec![];
    let stdin = io::stdin();
    for line in stdin.lock().lines() {
        let line = line.unwrap();
@@ -108,23 +76,14 @@ pub fn main() -> Result<()> {
            // Don't try and parse "metadata" like a key-lsn range
            continue;
        }
-        let (key_range, lsn_range) = parse_filename(filename);
-        files.push(Layer {
-            filename: filename.to_owned(),
-            key_range,
-            lsn_range,
-        });
+        let range = parse_filename(filename);
+        ranges.push(range);
    }

    // Collect all coordinates
    let mut keys: Vec<Key> = vec![];
    let mut lsns: Vec<Lsn> = vec![];
-    for Layer {
-        key_range: keyr,
-        lsn_range: lsnr,
-        ..
-    } in &files
-    {
+    for (keyr, lsnr) in &ranges {
        keys.push(keyr.start);
        keys.push(keyr.end);
        lsns.push(lsnr.start);
@@ -148,12 +107,7 @@ pub fn main() -> Result<()> {
            h: stretch * lsn_map.len() as f32
        }
    );
-    for Layer {
-        filename,
-        key_range: keyr,
-        lsn_range: lsnr,
-    } in &files
-    {
+    for (keyr, lsnr) in &ranges {
        let key_start = *key_map.get(&keyr.start).unwrap();
        let key_end = *key_map.get(&keyr.end).unwrap();
        let key_diff = key_end - key_start;
@@ -197,7 +151,6 @@ pub fn main() -> Result<()> {
            .fill(fill)
            .stroke(Stroke::Color(rgb(0, 0, 0), 0.1))
            .border_radius(0.4)
-            .comment(filename)
        );
    }
    println!("{}", EndSvg);
--- a/pageserver/pagebench/src/cmd/getpage_latest_lsn.rs
+++ b/pageserver/pagebench/src/cmd/getpage_latest_lsn.rs
@@ -312,12 +312,8 @@ async fn main_impl(
                    let (rel_tag, block_no) =
                        key_to_rel_block(key).expect("we filter non-rel-block keys out above");
                    PagestreamGetPageRequest {
-                        request_lsn: if rng.gen_bool(args.req_latest_probability) {
-                            Lsn::MAX
-                        } else {
-                            r.timeline_lsn
-                        },
-                        not_modified_since: r.timeline_lsn,
+                        latest: rng.gen_bool(args.req_latest_probability),
+                        lsn: r.timeline_lsn,
                        rel: rel_tag,
                        blkno: block_no,
                    }
--- a/pageserver/src/aux_file.rs
+++ b/pageserver/src/aux_file.rs
@@ -1,112 +0,0 @@
-use pageserver_api::key::{Key, AUX_KEY_PREFIX, METADATA_KEY_SIZE};
-use tracing::warn;
-
-/// Create a metadata key from a hash, encoded as [AUX_KEY_PREFIX, 2B directory prefix, first 13B of 128b xxhash].
-fn aux_hash_to_metadata_key(dir_level1: u8, dir_level2: u8, data: &[u8]) -> Key {
-    let mut key = [0; METADATA_KEY_SIZE];
-    let hash = twox_hash::xxh3::hash128(data).to_be_bytes();
-    key[0] = AUX_KEY_PREFIX;
-    key[1] = dir_level1;
-    key[2] = dir_level2;
-    key[3..16].copy_from_slice(&hash[0..13]);
-    Key::from_metadata_key_fixed_size(&key)
-}
-
-const AUX_DIR_PG_LOGICAL: u8 = 0x01;
-const AUX_DIR_PG_REPLSLOT: u8 = 0x02;
-const AUX_DIR_PG_UNKNOWN: u8 = 0xFF;
-
-/// Encode the aux file into a fixed-size key.
-///
-/// The first byte is the AUX key prefix. We use the next 2 bytes of the key for the directory / aux file type.
-/// We have one-to-one mapping for each of the aux file that we support. We hash the remaining part of the path
-/// (usually a single file name, or several components) into 13-byte hash. The way we determine the 2-byte prefix
-/// is roughly based on the first two components of the path, one unique number for one component.
-///
-/// * pg_logical/mappings -> 0x0101
-/// * pg_logical/snapshots -> 0x0102
-/// * pg_logical/replorigin_checkpoint -> 0x0103
-/// * pg_logical/others -> 0x01FF
-/// * pg_replslot/ -> 0x0201
-/// * others -> 0xFFFF
-///
-/// If you add new AUX files to this function, please also add a test case to `test_encoding_portable`.
-/// The new file type must have never been written to the storage before. Otherwise, there could be data
-/// corruptions as the new file belongs to a new prefix but it might have been stored under the `others` prefix.
-pub fn encode_aux_file_key(path: &str) -> Key {
-    if let Some(fname) = path.strip_prefix("pg_logical/mappings/") {
-        aux_hash_to_metadata_key(AUX_DIR_PG_LOGICAL, 0x01, fname.as_bytes())
-    } else if let Some(fname) = path.strip_prefix("pg_logical/snapshots/") {
-        aux_hash_to_metadata_key(AUX_DIR_PG_LOGICAL, 0x02, fname.as_bytes())
-    } else if path == "pg_logical/replorigin_checkpoint" {
-        aux_hash_to_metadata_key(AUX_DIR_PG_LOGICAL, 0x03, b"")
-    } else if let Some(fname) = path.strip_prefix("pg_logical/") {
-        if cfg!(debug_assertions) {
-            warn!(
-                "unsupported pg_logical aux file type: {}, putting to 0x01FF, would affect path scanning",
-                path
-            );
-        }
-        aux_hash_to_metadata_key(AUX_DIR_PG_LOGICAL, 0xFF, fname.as_bytes())
-    } else if let Some(fname) = path.strip_prefix("pg_replslot/") {
-        aux_hash_to_metadata_key(AUX_DIR_PG_REPLSLOT, 0x01, fname.as_bytes())
-    } else {
-        if cfg!(debug_assertions) {
-            warn!(
-                "unsupported aux file type: {}, putting to 0xFFFF, would affect path scanning",
-                path
-            );
-        }
-        aux_hash_to_metadata_key(AUX_DIR_PG_UNKNOWN, 0xFF, path.as_bytes())
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_hash_portable() {
-        // AUX file encoding requires the hash to be portable across all platforms. This test case checks
-        // if the algorithm produces the same hash across different environments.
-        assert_eq!(
-            305317690835051308206966631765527126151,
-            twox_hash::xxh3::hash128("test1".as_bytes())
-        );
-        assert_eq!(
-            85104974691013376326742244813280798847,
-            twox_hash::xxh3::hash128("test/test2".as_bytes())
-        );
-        assert_eq!(0, twox_hash::xxh3::hash128("".as_bytes()));
-    }
-
-    #[test]
-    fn test_encoding_portable() {
-        // To correct retrieve AUX files, the generated keys for the same file must be the same for all versions
-        // of the page server.
-        assert_eq!(
-            "6200000101E5B20C5F8DD5AA3289D6D9EAFA",
-            encode_aux_file_key("pg_logical/mappings/test1").to_string()
-        );
-        assert_eq!(
-            "620000010239AAC544893139B26F501B97E6",
-            encode_aux_file_key("pg_logical/snapshots/test2").to_string()
-        );
-        assert_eq!(
-            "620000010300000000000000000000000000",
-            encode_aux_file_key("pg_logical/replorigin_checkpoint").to_string()
-        );
-        assert_eq!(
-            "62000001FF8635AF2134B7266EC5B4189FD6",
-            encode_aux_file_key("pg_logical/unsupported").to_string()
-        );
-        assert_eq!(
-            "6200000201772D0E5D71DE14DA86142A1619",
-            encode_aux_file_key("pg_replslot/test3").to_string()
-        );
-        assert_eq!(
-            "620000FFFF1866EBEB53B807B26A2416F317",
-            encode_aux_file_key("other_file_not_supported").to_string()
-        );
-    }
-}
--- a/pageserver/src/basebackup.rs
+++ b/pageserver/src/basebackup.rs
@@ -13,7 +13,7 @@
 use anyhow::{anyhow, bail, ensure, Context};
 use bytes::{BufMut, Bytes, BytesMut};
 use fail::fail_point;
-use pageserver_api::key::{key_to_slru_block, rel_block_to_key, Key};
+use pageserver_api::key::{key_to_slru_block, Key};
 use postgres_ffi::pg_constants;
 use std::fmt::Write as FmtWrite;
 use std::time::SystemTime;
@@ -263,10 +263,7 @@ where
                .timeline
                .get_slru_keyspace(Version::Lsn(self.lsn), self.ctx)
                .await?
-                .partition(
-                    self.timeline.get_shard_identity(),
-                    Timeline::MAX_GET_VECTORED_KEYS * BLCKSZ as u64,
-                );
+                .partition(Timeline::MAX_GET_VECTORED_KEYS * BLCKSZ as u64);

            let mut slru_builder = SlruSegmentsBuilder::new(&mut self.ar);

@@ -300,20 +297,7 @@ where
                if rel.forknum == INIT_FORKNUM {
                    // I doubt we need _init fork itself, but having it at least
                    // serves as a marker relation is unlogged.
-                    if let Err(_e) = self.add_rel(rel, rel).await {
-                        if self
-                            .timeline
-                            .get_shard_identity()
-                            .is_key_buggy_forknum(&rel_block_to_key(rel, 0x0))
-                        {
-                            // Workaround https://github.com/neondatabase/neon/issues/7451 -- if we have an unlogged relation
-                            // whose INIT_FORKNUM is not correctly on shard zero, then omit it in the basebackup.  This allows
-                            // postgres to start up.  The relation won't work, but it will be possible to DROP TABLE on it and
-                            // recreate.
-                            tracing::warn!("Omitting relation {rel} for issue #7451: drop and recreate this unlogged relation");
-                            continue;
-                        }
-                    };
+                    self.add_rel(rel, rel).await?;
                    self.add_rel(rel, rel.with_forknum(MAIN_FORKNUM)).await?;
                    continue;
                }
@@ -379,7 +363,7 @@ where
    async fn add_rel(&mut self, src: RelTag, dst: RelTag) -> anyhow::Result<()> {
        let nblocks = self
            .timeline
-            .get_rel_size(src, Version::Lsn(self.lsn), self.ctx)
+            .get_rel_size(src, Version::Lsn(self.lsn), false, self.ctx)
            .await?;

        // If the relation is empty, create an empty file
@@ -400,7 +384,7 @@ where
            for blknum in startblk..endblk {
                let img = self
                    .timeline
-                    .get_rel_page_at_lsn(src, blknum, Version::Lsn(self.lsn), self.ctx)
+                    .get_rel_page_at_lsn(src, blknum, Version::Lsn(self.lsn), false, self.ctx)
                    .await?;
                segment_data.extend_from_slice(&img[..]);
            }
--- a/pageserver/src/bin/pageserver.rs
+++ b/pageserver/src/bin/pageserver.rs
@@ -121,10 +121,8 @@ fn main() -> anyhow::Result<()> {
        &[("node_id", &conf.id.to_string())],
    );

-    // after setting up logging, log the effective IO engine choice and read path implementations
+    // after setting up logging, log the effective IO engine choice
    info!(?conf.virtual_file_io_engine, "starting with virtual_file IO engine");
-    info!(?conf.get_impl, "starting with get page implementation");
-    info!(?conf.get_vectored_impl, "starting with vectored get page implementation");

    let tenants_path = conf.tenants_path();
    if !tenants_path.exists() {
--- a/pageserver/src/config.rs
+++ b/pageserver/src/config.rs
@@ -30,9 +30,9 @@ use utils::{
    logging::LogFormat,
 };

+use crate::tenant::config::TenantConfOpt;
 use crate::tenant::timeline::GetVectoredImpl;
 use crate::tenant::vectored_blob_io::MaxVectoredReadBytes;
-use crate::tenant::{config::TenantConfOpt, timeline::GetImpl};
 use crate::tenant::{
    TENANTS_SEGMENT_NAME, TENANT_DELETED_MARKER_FILE_NAME, TIMELINES_SEGMENT_NAME,
 };
@@ -91,8 +91,6 @@ pub mod defaults {

    pub const DEFAULT_GET_VECTORED_IMPL: &str = "sequential";

-    pub const DEFAULT_GET_IMPL: &str = "legacy";
-
    pub const DEFAULT_MAX_VECTORED_READ_BYTES: usize = 128 * 1024; // 128 KiB

    pub const DEFAULT_VALIDATE_VECTORED_GET: bool = true;
@@ -140,8 +138,6 @@ pub mod defaults {

 #get_vectored_impl = '{DEFAULT_GET_VECTORED_IMPL}'

-#get_impl = '{DEFAULT_GET_IMPL}'
-
 #max_vectored_read_bytes = '{DEFAULT_MAX_VECTORED_READ_BYTES}'

 #validate_vectored_get = '{DEFAULT_VALIDATE_VECTORED_GET}'
@@ -288,8 +284,6 @@ pub struct PageServerConf {

    pub get_vectored_impl: GetVectoredImpl,

-    pub get_impl: GetImpl,
-
    pub max_vectored_read_bytes: MaxVectoredReadBytes,

    pub validate_vectored_get: bool,
@@ -420,8 +414,6 @@ struct PageServerConfigBuilder {

    get_vectored_impl: BuilderValue<GetVectoredImpl>,

-    get_impl: BuilderValue<GetImpl>,
-
    max_vectored_read_bytes: BuilderValue<MaxVectoredReadBytes>,

    validate_vectored_get: BuilderValue<bool>,
@@ -511,7 +503,6 @@ impl PageServerConfigBuilder {
            virtual_file_io_engine: Set(DEFAULT_VIRTUAL_FILE_IO_ENGINE.parse().unwrap()),

            get_vectored_impl: Set(DEFAULT_GET_VECTORED_IMPL.parse().unwrap()),
-            get_impl: Set(DEFAULT_GET_IMPL.parse().unwrap()),
            max_vectored_read_bytes: Set(MaxVectoredReadBytes(
                NonZeroUsize::new(DEFAULT_MAX_VECTORED_READ_BYTES).unwrap(),
            )),
@@ -690,10 +681,6 @@ impl PageServerConfigBuilder {
        self.get_vectored_impl = BuilderValue::Set(value);
    }

-    pub fn get_impl(&mut self, value: GetImpl) {
-        self.get_impl = BuilderValue::Set(value);
-    }
-
    pub fn get_max_vectored_read_bytes(&mut self, value: MaxVectoredReadBytes) {
        self.max_vectored_read_bytes = BuilderValue::Set(value);
    }
@@ -763,7 +750,6 @@ impl PageServerConfigBuilder {
                secondary_download_concurrency,
                ingest_batch_size,
                get_vectored_impl,
-                get_impl,
                max_vectored_read_bytes,
                validate_vectored_get,
                ephemeral_bytes_per_memory_kb,
@@ -1049,9 +1035,6 @@ impl PageServerConf {
                "get_vectored_impl" => {
                    builder.get_vectored_impl(parse_toml_from_str("get_vectored_impl", item)?)
                }
-                "get_impl" => {
-                    builder.get_impl(parse_toml_from_str("get_impl", item)?)
-                }
                "max_vectored_read_bytes" => {
                    let bytes = parse_toml_u64("max_vectored_read_bytes", item)? as usize;
                    builder.get_max_vectored_read_bytes(
@@ -1143,7 +1126,6 @@ impl PageServerConf {
            ingest_batch_size: defaults::DEFAULT_INGEST_BATCH_SIZE,
            virtual_file_io_engine: DEFAULT_VIRTUAL_FILE_IO_ENGINE.parse().unwrap(),
            get_vectored_impl: defaults::DEFAULT_GET_VECTORED_IMPL.parse().unwrap(),
-            get_impl: defaults::DEFAULT_GET_IMPL.parse().unwrap(),
            max_vectored_read_bytes: MaxVectoredReadBytes(
                NonZeroUsize::new(defaults::DEFAULT_MAX_VECTORED_READ_BYTES)
                    .expect("Invalid default constant"),
@@ -1383,7 +1365,6 @@ background_task_maximum_delay = '334 s'
                ingest_batch_size: defaults::DEFAULT_INGEST_BATCH_SIZE,
                virtual_file_io_engine: DEFAULT_VIRTUAL_FILE_IO_ENGINE.parse().unwrap(),
                get_vectored_impl: defaults::DEFAULT_GET_VECTORED_IMPL.parse().unwrap(),
-                get_impl: defaults::DEFAULT_GET_IMPL.parse().unwrap(),
                max_vectored_read_bytes: MaxVectoredReadBytes(
                    NonZeroUsize::new(defaults::DEFAULT_MAX_VECTORED_READ_BYTES)
                        .expect("Invalid default constant")
@@ -1457,7 +1438,6 @@ background_task_maximum_delay = '334 s'
                ingest_batch_size: 100,
                virtual_file_io_engine: DEFAULT_VIRTUAL_FILE_IO_ENGINE.parse().unwrap(),
                get_vectored_impl: defaults::DEFAULT_GET_VECTORED_IMPL.parse().unwrap(),
-                get_impl: defaults::DEFAULT_GET_IMPL.parse().unwrap(),
                max_vectored_read_bytes: MaxVectoredReadBytes(
                    NonZeroUsize::new(defaults::DEFAULT_MAX_VECTORED_READ_BYTES)
                        .expect("Invalid default constant")
@@ -1577,7 +1557,6 @@ broker_endpoint = '{broker_endpoint}'
                        endpoint: Some(endpoint.clone()),
                        concurrency_limit: s3_concurrency_limit,
                        max_keys_per_list_response: None,
-                        upload_storage_class: None,
                    }),
                    timeout: RemoteStorageConfig::DEFAULT_TIMEOUT,
                },
--- a/pageserver/src/http/routes.rs
+++ b/pageserver/src/http/routes.rs
@@ -19,8 +19,6 @@ use pageserver_api::models::LocationConfigListResponse;
 use pageserver_api::models::ShardParameters;
 use pageserver_api::models::TenantDetails;
 use pageserver_api::models::TenantLocationConfigResponse;
-use pageserver_api::models::TenantScanRemoteStorageResponse;
-use pageserver_api::models::TenantScanRemoteStorageShard;
 use pageserver_api::models::TenantShardLocation;
 use pageserver_api::models::TenantShardSplitRequest;
 use pageserver_api::models::TenantShardSplitResponse;
@@ -31,7 +29,6 @@ use pageserver_api::models::{
 };
 use pageserver_api::shard::ShardCount;
 use pageserver_api::shard::TenantShardId;
-use remote_storage::DownloadError;
 use remote_storage::GenericRemoteStorage;
 use remote_storage::TimeTravelError;
 use tenant_size_model::{SizeResult, StorageModel};
@@ -57,9 +54,6 @@ use crate::tenant::mgr::{
 };
 use crate::tenant::mgr::{TenantSlot, UpsertLocationError};
 use crate::tenant::remote_timeline_client;
-use crate::tenant::remote_timeline_client::download_index_part;
-use crate::tenant::remote_timeline_client::list_remote_tenant_shards;
-use crate::tenant::remote_timeline_client::list_remote_timelines;
 use crate::tenant::secondary::SecondaryController;
 use crate::tenant::size::ModelInputs;
 use crate::tenant::storage_layer::LayerAccessStatsReset;
@@ -166,9 +160,6 @@ impl From<PageReconstructError> for ApiError {
    fn from(pre: PageReconstructError) -> ApiError {
        match pre {
            PageReconstructError::Other(pre) => ApiError::InternalServerError(pre),
-            PageReconstructError::MissingKey(e) => {
-                ApiError::InternalServerError(anyhow::anyhow!("{e}"))
-            }
            PageReconstructError::Cancelled => {
                ApiError::InternalServerError(anyhow::anyhow!("request was cancelled"))
            }
@@ -2041,79 +2032,6 @@ async fn secondary_upload_handler(
    json_response(StatusCode::OK, ())
 }

-async fn tenant_scan_remote_handler(
-    request: Request<Body>,
-    cancel: CancellationToken,
-) -> Result<Response<Body>, ApiError> {
-    let state = get_state(&request);
-    let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
-
-    let Some(remote_storage) = state.remote_storage.as_ref() else {
-        return Err(ApiError::BadRequest(anyhow::anyhow!(
-            "Remote storage not configured"
-        )));
-    };
-
-    let mut response = TenantScanRemoteStorageResponse::default();
-
-    let (shards, _other_keys) =
-        list_remote_tenant_shards(remote_storage, tenant_id, cancel.clone())
-            .await
-            .map_err(|e| ApiError::InternalServerError(anyhow::anyhow!(e)))?;
-
-    for tenant_shard_id in shards {
-        let (timeline_ids, _other_keys) =
-            list_remote_timelines(remote_storage, tenant_shard_id, cancel.clone())
-                .await
-                .map_err(|e| ApiError::InternalServerError(anyhow::anyhow!(e)))?;
-
-        let mut generation = Generation::none();
-        for timeline_id in timeline_ids {
-            match download_index_part(
-                remote_storage,
-                &tenant_shard_id,
-                &timeline_id,
-                Generation::MAX,
-                &cancel,
-            )
-            .instrument(info_span!("download_index_part",
-                         tenant_id=%tenant_shard_id.tenant_id,
-                         shard_id=%tenant_shard_id.shard_slug(),
-                         %timeline_id))
-            .await
-            {
-                Ok((index_part, index_generation)) => {
-                    tracing::info!("Found timeline {tenant_shard_id}/{timeline_id} metadata (gen {index_generation:?}, {} layers, {} consistent LSN)",
-                        index_part.layer_metadata.len(), index_part.get_disk_consistent_lsn());
-                    generation = std::cmp::max(generation, index_generation);
-                }
-                Err(DownloadError::NotFound) => {
-                    // This is normal for tenants that were created with multiple shards: they have an unsharded path
-                    // containing the timeline's initdb tarball but no index.  Otherwise it is a bit strange.
-                    tracing::info!("Timeline path {tenant_shard_id}/{timeline_id} exists in remote storage but has no index, skipping");
-                    continue;
-                }
-                Err(e) => {
-                    return Err(ApiError::InternalServerError(anyhow::anyhow!(e)));
-                }
-            };
-        }
-
-        response.shards.push(TenantScanRemoteStorageShard {
-            tenant_shard_id,
-            generation: generation.into(),
-        });
-    }
-
-    if response.shards.is_empty() {
-        return Err(ApiError::NotFound(
-            anyhow::anyhow!("No shards found for tenant ID {tenant_id}").into(),
-        ));
-    }
-
-    json_response(StatusCode::OK, response)
-}
-
 async fn secondary_download_handler(
    request: Request<Body>,
    _cancel: CancellationToken,
@@ -2510,9 +2428,6 @@ pub fn make_router(
        .post("/v1/tenant/:tenant_shard_id/heatmap_upload", |r| {
            api_handler(r, secondary_upload_handler)
        })
-        .get("/v1/tenant/:tenant_id/scan_remote_storage", |r| {
-            api_handler(r, tenant_scan_remote_handler)
-        })
        .put("/v1/disk_usage_eviction/run", |r| {
            api_handler(r, disk_usage_eviction_run)
        })
--- a/pageserver/src/lib.rs
+++ b/pageserver/src/lib.rs
@@ -12,7 +12,6 @@ pub mod disk_usage_eviction_task;
 pub mod http;
 pub mod import_datadir;
 pub use pageserver_api::keyspace;
-pub mod aux_file;
 pub mod metrics;
 pub mod page_cache;
 pub mod page_service;
--- a/pageserver/src/metrics.rs
+++ b/pageserver/src/metrics.rs
@@ -51,9 +51,6 @@ pub(crate) enum StorageTimeOperation {
    #[strum(serialize = "gc")]
    Gc,

-    #[strum(serialize = "update gc info")]
-    UpdateGcInfo,
-
    #[strum(serialize = "create tenant")]
    CreateTenant,
 }
@@ -89,58 +86,41 @@ pub(crate) static STORAGE_TIME_GLOBAL: Lazy<HistogramVec> = Lazy::new(|| {
    .expect("failed to define a metric")
 });

-pub(crate) static READ_NUM_LAYERS_VISITED: Lazy<Histogram> = Lazy::new(|| {
+pub(crate) static READ_NUM_FS_LAYERS: Lazy<Histogram> = Lazy::new(|| {
    register_histogram!(
-        "pageserver_layers_visited_per_read_global",
-        "Number of layers visited to reconstruct one key",
-        vec![1.0, 4.0, 8.0, 16.0, 32.0, 64.0, 128.0, 256.0, 512.0, 1024.0],
-    )
-    .expect("failed to define a metric")
-});
-
-pub(crate) static VEC_READ_NUM_LAYERS_VISITED: Lazy<Histogram> = Lazy::new(|| {
-    register_histogram!(
-        "pageserver_layers_visited_per_vectored_read_global",
-        "Average number of layers visited to reconstruct one key",
-        vec![1.0, 4.0, 8.0, 16.0, 32.0, 64.0, 128.0, 256.0, 512.0, 1024.0],
+        "pageserver_read_num_fs_layers",
+        "Number of persistent layers accessed for processing a read request, including those in the cache",
+        vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 10.0, 20.0, 50.0, 100.0],
    )
    .expect("failed to define a metric")
 });

 // Metrics collected on operations on the storage repository.
-#[derive(
-    Clone, Copy, enum_map::Enum, strum_macros::EnumString, strum_macros::Display, IntoStaticStr,
-)]
-pub(crate) enum GetKind {
-    Singular,
-    Vectored,
-}

 pub(crate) struct ReconstructTimeMetrics {
-    singular: Histogram,
-    vectored: Histogram,
+    ok: Histogram,
+    err: Histogram,
 }

 pub(crate) static RECONSTRUCT_TIME: Lazy<ReconstructTimeMetrics> = Lazy::new(|| {
    let inner = register_histogram_vec!(
        "pageserver_getpage_reconstruct_seconds",
        "Time spent in reconstruct_value (reconstruct a page from deltas)",
-        &["get_kind"],
+        &["result"],
        CRITICAL_OP_BUCKETS.into(),
    )
    .expect("failed to define a metric");
-
    ReconstructTimeMetrics {
-        singular: inner.with_label_values(&[GetKind::Singular.into()]),
-        vectored: inner.with_label_values(&[GetKind::Vectored.into()]),
+        ok: inner.get_metric_with_label_values(&["ok"]).unwrap(),
+        err: inner.get_metric_with_label_values(&["err"]).unwrap(),
    }
 });

 impl ReconstructTimeMetrics {
-    pub(crate) fn for_get_kind(&self, get_kind: GetKind) -> &Histogram {
-        match get_kind {
-            GetKind::Singular => &self.singular,
-            GetKind::Vectored => &self.vectored,
+    pub(crate) fn for_result<T, E>(&self, result: &Result<T, E>) -> &Histogram {
+        match result {
+            Ok(_) => &self.ok,
+            Err(_) => &self.err,
        }
    }
 }
@@ -153,33 +133,13 @@ pub(crate) static MATERIALIZED_PAGE_CACHE_HIT_DIRECT: Lazy<IntCounter> = Lazy::n
    .expect("failed to define a metric")
 });

-pub(crate) struct ReconstructDataTimeMetrics {
-    singular: Histogram,
-    vectored: Histogram,
-}
-
-impl ReconstructDataTimeMetrics {
-    pub(crate) fn for_get_kind(&self, get_kind: GetKind) -> &Histogram {
-        match get_kind {
-            GetKind::Singular => &self.singular,
-            GetKind::Vectored => &self.vectored,
-        }
-    }
-}
-
-pub(crate) static GET_RECONSTRUCT_DATA_TIME: Lazy<ReconstructDataTimeMetrics> = Lazy::new(|| {
-    let inner = register_histogram_vec!(
+pub(crate) static GET_RECONSTRUCT_DATA_TIME: Lazy<Histogram> = Lazy::new(|| {
+    register_histogram!(
        "pageserver_getpage_get_reconstruct_data_seconds",
        "Time spent in get_reconstruct_value_data",
-        &["get_kind"],
        CRITICAL_OP_BUCKETS.into(),
    )
-    .expect("failed to define a metric");
-
-    ReconstructDataTimeMetrics {
-        singular: inner.with_label_values(&[GetKind::Singular.into()]),
-        vectored: inner.with_label_values(&[GetKind::Vectored.into()]),
-    }
+    .expect("failed to define a metric")
 });

 pub(crate) static MATERIALIZED_PAGE_CACHE_HIT: Lazy<IntCounter> = Lazy::new(|| {
@@ -1522,6 +1482,35 @@ pub(crate) static DELETION_QUEUE: Lazy<DeletionQueueMetrics> = Lazy::new(|| {
 }
 });

+pub(crate) struct WalIngestMetrics {
+    pub(crate) bytes_received: IntCounter,
+    pub(crate) records_received: IntCounter,
+    pub(crate) records_committed: IntCounter,
+    pub(crate) records_filtered: IntCounter,
+}
+
+pub(crate) static WAL_INGEST: Lazy<WalIngestMetrics> = Lazy::new(|| WalIngestMetrics {
+    bytes_received: register_int_counter!(
+        "pageserver_wal_ingest_bytes_received",
+        "Bytes of WAL ingested from safekeepers",
+    )
+    .unwrap(),
+    records_received: register_int_counter!(
+        "pageserver_wal_ingest_records_received",
+        "Number of WAL records received from safekeepers"
+    )
+    .expect("failed to define a metric"),
+    records_committed: register_int_counter!(
+        "pageserver_wal_ingest_records_committed",
+        "Number of WAL records which resulted in writes to pageserver storage"
+    )
+    .expect("failed to define a metric"),
+    records_filtered: register_int_counter!(
+        "pageserver_wal_ingest_records_filtered",
+        "Number of WAL records filtered out due to sharding"
+    )
+    .expect("failed to define a metric"),
+});
 pub(crate) struct SecondaryModeMetrics {
    pub(crate) upload_heatmap: IntCounter,
    pub(crate) upload_heatmap_errors: IntCounter,
@@ -1723,43 +1712,6 @@ macro_rules! redo_bytes_histogram_count_buckets {
    };
 }

-pub(crate) struct WalIngestMetrics {
-    pub(crate) bytes_received: IntCounter,
-    pub(crate) records_received: IntCounter,
-    pub(crate) records_committed: IntCounter,
-    pub(crate) records_filtered: IntCounter,
-    pub(crate) time_spent_on_ingest: Histogram,
-}
-
-pub(crate) static WAL_INGEST: Lazy<WalIngestMetrics> = Lazy::new(|| WalIngestMetrics {
-    bytes_received: register_int_counter!(
-        "pageserver_wal_ingest_bytes_received",
-        "Bytes of WAL ingested from safekeepers",
-    )
-    .unwrap(),
-    records_received: register_int_counter!(
-        "pageserver_wal_ingest_records_received",
-        "Number of WAL records received from safekeepers"
-    )
-    .expect("failed to define a metric"),
-    records_committed: register_int_counter!(
-        "pageserver_wal_ingest_records_committed",
-        "Number of WAL records which resulted in writes to pageserver storage"
-    )
-    .expect("failed to define a metric"),
-    records_filtered: register_int_counter!(
-        "pageserver_wal_ingest_records_filtered",
-        "Number of WAL records filtered out due to sharding"
-    )
-    .expect("failed to define a metric"),
-    time_spent_on_ingest: register_histogram!(
-        "pageserver_wal_ingest_put_value_seconds",
-        "Actual time spent on ingesting a record",
-        redo_histogram_time_buckets!(),
-    )
-    .expect("failed to define a metric"),
-});
-
 pub(crate) static WAL_REDO_TIME: Lazy<Histogram> = Lazy::new(|| {
    register_histogram!(
        "pageserver_wal_redo_seconds",
@@ -1913,22 +1865,6 @@ impl StorageTimeMetricsTimer {
        self.metrics.timeline_count.inc();
        self.metrics.global_histogram.observe(duration);
    }
-
-    /// Turns this timer into a timer, which will always record -- usually this means recording
-    /// regardless an early `?` path was taken in a function.
-    pub(crate) fn record_on_drop(self) -> AlwaysRecordingStorageTimeMetricsTimer {
-        AlwaysRecordingStorageTimeMetricsTimer(Some(self))
-    }
-}
-
-pub(crate) struct AlwaysRecordingStorageTimeMetricsTimer(Option<StorageTimeMetricsTimer>);
-
-impl Drop for AlwaysRecordingStorageTimeMetricsTimer {
-    fn drop(&mut self) {
-        if let Some(inner) = self.0.take() {
-            inner.stop_and_record();
-        }
-    }
 }

 /// Timing facilities for an globally histogrammed metric, which is supported by per tenant and
@@ -1989,7 +1925,6 @@ pub(crate) struct TimelineMetrics {
    pub imitate_logical_size_histo: StorageTimeMetrics,
    pub load_layer_map_histo: StorageTimeMetrics,
    pub garbage_collect_histo: StorageTimeMetrics,
-    pub update_gc_info_histo: StorageTimeMetrics,
    pub last_record_gauge: IntGauge,
    resident_physical_size_gauge: UIntGauge,
    /// copy of LayeredTimeline.current_logical_size
@@ -2050,12 +1985,6 @@ impl TimelineMetrics {
            &shard_id,
            &timeline_id,
        );
-        let update_gc_info_histo = StorageTimeMetrics::new(
-            StorageTimeOperation::UpdateGcInfo,
-            &tenant_id,
-            &shard_id,
-            &timeline_id,
-        );
        let last_record_gauge = LAST_RECORD_LSN
            .get_metric_with_label_values(&[&tenant_id, &shard_id, &timeline_id])
            .unwrap();
@@ -2098,7 +2027,6 @@ impl TimelineMetrics {
            logical_size_histo,
            imitate_logical_size_histo,
            garbage_collect_histo,
-            update_gc_info_histo,
            load_layer_map_histo,
            last_record_gauge,
            resident_physical_size_gauge,
@@ -2843,8 +2771,7 @@ pub fn preinitialize_metrics() {

    // histograms
    [
-        &READ_NUM_LAYERS_VISITED,
-        &VEC_READ_NUM_LAYERS_VISITED,
+        &READ_NUM_FS_LAYERS,
        &WAIT_LSN_TIME,
        &WAL_REDO_TIME,
        &WAL_REDO_RECORDS_HISTOGRAM,
--- a/pageserver/src/page_service.rs
+++ b/pageserver/src/page_service.rs
@@ -1,5 +1,13 @@
+//
 //! The Page Service listens for client connections and serves their GetPage@LSN
 //! requests.
+//
+//   It is possible to connect here using usual psql/pgbench/libpq. Following
+// commands are supported now:
+//     *status* -- show actual info about this pageserver,
+//     *pagestream* -- enter mode where smgr and pageserver talk with their
+//  custom protocol.
+//

 use anyhow::Context;
 use async_compression::tokio::write::GzipEncoder;
@@ -15,7 +23,7 @@ use pageserver_api::models::{
    PagestreamErrorResponse, PagestreamExistsRequest, PagestreamExistsResponse,
    PagestreamFeMessage, PagestreamGetPageRequest, PagestreamGetPageResponse,
    PagestreamGetSlruSegmentRequest, PagestreamGetSlruSegmentResponse, PagestreamNblocksRequest,
-    PagestreamNblocksResponse, PagestreamProtocolVersion,
+    PagestreamNblocksResponse,
 };
 use pageserver_api::shard::ShardIndex;
 use pageserver_api::shard::ShardNumber;
@@ -543,7 +551,6 @@ impl PageServerHandler {
        pgb: &mut PostgresBackend<IO>,
        tenant_id: TenantId,
        timeline_id: TimelineId,
-        protocol_version: PagestreamProtocolVersion,
        ctx: RequestContext,
    ) -> Result<(), QueryError>
    where
@@ -606,15 +613,14 @@ impl PageServerHandler {
                t.trace(&copy_data_bytes)
            }

-            let neon_fe_msg =
-                PagestreamFeMessage::parse(&mut copy_data_bytes.reader(), protocol_version)?;
+            let neon_fe_msg = PagestreamFeMessage::parse(&mut copy_data_bytes.reader())?;

            // TODO: We could create a new per-request context here, with unique ID.
            // Currently we use the same per-timeline context for all requests

            let (response, span) = match neon_fe_msg {
                PagestreamFeMessage::Exists(req) => {
-                    let span = tracing::info_span!("handle_get_rel_exists_request", rel = %req.rel, req_lsn = %req.request_lsn);
+                    let span = tracing::info_span!("handle_get_rel_exists_request", rel = %req.rel, req_lsn = %req.lsn);
                    (
                        self.handle_get_rel_exists_request(tenant_id, timeline_id, &req, &ctx)
                            .instrument(span.clone())
@@ -623,7 +629,7 @@ impl PageServerHandler {
                    )
                }
                PagestreamFeMessage::Nblocks(req) => {
-                    let span = tracing::info_span!("handle_get_nblocks_request", rel = %req.rel, req_lsn = %req.request_lsn);
+                    let span = tracing::info_span!("handle_get_nblocks_request", rel = %req.rel, req_lsn = %req.lsn);
                    (
                        self.handle_get_nblocks_request(tenant_id, timeline_id, &req, &ctx)
                            .instrument(span.clone())
@@ -633,7 +639,7 @@ impl PageServerHandler {
                }
                PagestreamFeMessage::GetPage(req) => {
                    // shard_id is filled in by the handler
-                    let span = tracing::info_span!("handle_get_page_at_lsn_request", rel = %req.rel, blkno = %req.blkno, req_lsn = %req.request_lsn);
+                    let span = tracing::info_span!("handle_get_page_at_lsn_request", rel = %req.rel, blkno = %req.blkno, req_lsn = %req.lsn);
                    (
                        self.handle_get_page_at_lsn_request(tenant_id, timeline_id, &req, &ctx)
                            .instrument(span.clone())
@@ -642,7 +648,7 @@ impl PageServerHandler {
                    )
                }
                PagestreamFeMessage::DbSize(req) => {
-                    let span = tracing::info_span!("handle_db_size_request", dbnode = %req.dbnode, req_lsn = %req.request_lsn);
+                    let span = tracing::info_span!("handle_db_size_request", dbnode = %req.dbnode, req_lsn = %req.lsn);
                    (
                        self.handle_db_size_request(tenant_id, timeline_id, &req, &ctx)
                            .instrument(span.clone())
@@ -651,7 +657,7 @@ impl PageServerHandler {
                    )
                }
                PagestreamFeMessage::GetSlruSegment(req) => {
-                    let span = tracing::info_span!("handle_get_slru_segment_request", kind = %req.kind, segno = %req.segno, req_lsn = %req.request_lsn);
+                    let span = tracing::info_span!("handle_get_slru_segment_request", kind = %req.kind, segno = %req.segno, req_lsn = %req.lsn);
                    (
                        self.handle_get_slru_segment_request(tenant_id, timeline_id, &req, &ctx)
                            .instrument(span.clone())
@@ -832,80 +838,78 @@ impl PageServerHandler {
    /// Helper function to handle the LSN from client request.
    ///
    /// Each GetPage (and Exists and Nblocks) request includes information about
-    /// which version of the page is being requested. The primary compute node
-    /// will always request the latest page version, by setting 'request_lsn' to
-    /// the last inserted or flushed WAL position, while a standby will request
-    /// a version at the LSN that it's currently caught up to.
+    /// which version of the page is being requested. The client can request the
+    /// latest version of the page, or the version that's valid at a particular
+    /// LSN. The primary compute node will always request the latest page
+    /// version, while a standby will request a version at the LSN that it's
+    /// currently caught up to.
    ///
    /// In either case, if the page server hasn't received the WAL up to the
    /// requested LSN yet, we will wait for it to arrive. The return value is
    /// the LSN that should be used to look up the page versions.
-    ///
-    /// In addition to the request LSN, each request carries another LSN,
-    /// 'not_modified_since', which is a hint to the pageserver that the client
-    /// knows that the page has not been modified between 'not_modified_since'
-    /// and the request LSN. This allows skipping the wait, as long as the WAL
-    /// up to 'not_modified_since' has arrived. If the client doesn't have any
-    /// information about when the page was modified, it will use
-    /// not_modified_since == lsn. If the client lies and sends a too low
-    /// not_modified_hint such that there are in fact later page versions, the
-    /// behavior is undefined: the pageserver may return any of the page versions
-    /// or an error.
    async fn wait_or_get_last_lsn(
        timeline: &Timeline,
-        request_lsn: Lsn,
-        not_modified_since: Lsn,
+        mut lsn: Lsn,
+        latest: bool,
        latest_gc_cutoff_lsn: &RcuReadGuard<Lsn>,
        ctx: &RequestContext,
    ) -> Result<Lsn, PageStreamError> {
-        let last_record_lsn = timeline.get_last_record_lsn();
+        if latest {
+            // Latest page version was requested. If LSN is given, it is a hint
+            // to the page server that there have been no modifications to the
+            // page after that LSN. If we haven't received WAL up to that point,
+            // wait until it arrives.
+            let last_record_lsn = timeline.get_last_record_lsn();

-        // Sanity check the request
-        if request_lsn < not_modified_since {
-            return Err(PageStreamError::BadRequest(
-                format!(
-                    "invalid request with request LSN {} and not_modified_since {}",
-                    request_lsn, not_modified_since,
-                )
-                .into(),
-            ));
-        }
-
-        if request_lsn < **latest_gc_cutoff_lsn {
-            // Check explicitly for INVALID just to get a less scary error message if the
-            // request is obviously bogus
-            return Err(if request_lsn == Lsn::INVALID {
-                PageStreamError::BadRequest("invalid LSN(0) in request".into())
+            // Note: this covers the special case that lsn == Lsn(0). That
+            // special case means "return the latest version whatever it is",
+            // and it's used for bootstrapping purposes, when the page server is
+            // connected directly to the compute node. That is needed because
+            // when you connect to the compute node, to receive the WAL, the
+            // walsender process will do a look up in the pg_authid catalog
+            // table for authentication. That poses a deadlock problem: the
+            // catalog table lookup will send a GetPage request, but the GetPage
+            // request will block in the page server because the recent WAL
+            // hasn't been received yet, and it cannot be received until the
+            // walsender completes the authentication and starts streaming the
+            // WAL.
+            if lsn <= last_record_lsn {
+                lsn = last_record_lsn;
            } else {
-                PageStreamError::BadRequest(format!(
-                        "tried to request a page version that was garbage collected. requested at {} gc cutoff {}",
-                        request_lsn, **latest_gc_cutoff_lsn
-                    ).into())
-            });
-        }
-
-        // Wait for WAL up to 'not_modified_since' to arrive, if necessary
-        if not_modified_since > last_record_lsn {
+                timeline
+                    .wait_lsn(
+                        lsn,
+                        crate::tenant::timeline::WaitLsnWaiter::PageService,
+                        ctx,
+                    )
+                    .await?;
+                // Since we waited for 'lsn' to arrive, that is now the last
+                // record LSN. (Or close enough for our purposes; the
+                // last-record LSN can advance immediately after we return
+                // anyway)
+            }
+        } else {
+            if lsn == Lsn(0) {
+                return Err(PageStreamError::BadRequest(
+                    "invalid LSN(0) in request".into(),
+                ));
+            }
            timeline
                .wait_lsn(
-                    not_modified_since,
+                    lsn,
                    crate::tenant::timeline::WaitLsnWaiter::PageService,
                    ctx,
                )
                .await?;
-            // Since we waited for 'not_modified_since' to arrive, that is now the last
-            // record LSN. (Or close enough for our purposes; the last-record LSN can
-            // advance immediately after we return anyway)
-            Ok(not_modified_since)
-        } else {
-            // It might be better to use max(not_modified_since, latest_gc_cutoff_lsn)
-            // here instead. That would give the same result, since we know that there
-            // haven't been any modifications since 'not_modified_since'. Using an older
-            // LSN might be faster, because that could allow skipping recent layers when
-            // finding the page. However, we have historically used 'last_record_lsn', so
-            // stick to that for now.
-            Ok(std::cmp::min(last_record_lsn, request_lsn))
        }
+
+        if lsn < **latest_gc_cutoff_lsn {
+            return Err(PageStreamError::BadRequest(format!(
+                "tried to request a page version that was garbage collected. requested at {} gc cutoff {}",
+                lsn, **latest_gc_cutoff_lsn
+            ).into()));
+        }
+        Ok(lsn)
    }

    #[instrument(skip_all, fields(shard_id))]
@@ -922,17 +926,12 @@ impl PageServerHandler {
            .start_timer(metrics::SmgrQueryType::GetRelExists, ctx);

        let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(
-            timeline,
-            req.request_lsn,
-            req.not_modified_since,
-            &latest_gc_cutoff_lsn,
-            ctx,
-        )
-        .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;

        let exists = timeline
-            .get_rel_exists(req.rel, Version::Lsn(lsn), ctx)
+            .get_rel_exists(req.rel, Version::Lsn(lsn), req.latest, ctx)
            .await?;

        Ok(PagestreamBeMessage::Exists(PagestreamExistsResponse {
@@ -955,17 +954,12 @@ impl PageServerHandler {
            .start_timer(metrics::SmgrQueryType::GetRelSize, ctx);

        let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(
-            timeline,
-            req.request_lsn,
-            req.not_modified_since,
-            &latest_gc_cutoff_lsn,
-            ctx,
-        )
-        .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;

        let n_blocks = timeline
-            .get_rel_size(req.rel, Version::Lsn(lsn), ctx)
+            .get_rel_size(req.rel, Version::Lsn(lsn), req.latest, ctx)
            .await?;

        Ok(PagestreamBeMessage::Nblocks(PagestreamNblocksResponse {
@@ -988,17 +982,18 @@ impl PageServerHandler {
            .start_timer(metrics::SmgrQueryType::GetDbSize, ctx);

        let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(
-            timeline,
-            req.request_lsn,
-            req.not_modified_since,
-            &latest_gc_cutoff_lsn,
-            ctx,
-        )
-        .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;

        let total_blocks = timeline
-            .get_db_size(DEFAULTTABLESPACE_OID, req.dbnode, Version::Lsn(lsn), ctx)
+            .get_db_size(
+                DEFAULTTABLESPACE_OID,
+                req.dbnode,
+                Version::Lsn(lsn),
+                req.latest,
+                ctx,
+            )
            .await?;
        let db_size = total_blocks as i64 * BLCKSZ as i64;

@@ -1165,17 +1160,12 @@ impl PageServerHandler {
            .start_timer(metrics::SmgrQueryType::GetPageAtLsn, ctx);

        let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(
-            timeline,
-            req.request_lsn,
-            req.not_modified_since,
-            &latest_gc_cutoff_lsn,
-            ctx,
-        )
-        .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;

        let page = timeline
-            .get_rel_page_at_lsn(req.rel, req.blkno, Version::Lsn(lsn), ctx)
+            .get_rel_page_at_lsn(req.rel, req.blkno, Version::Lsn(lsn), req.latest, ctx)
            .await?;

        Ok(PagestreamBeMessage::GetPage(PagestreamGetPageResponse {
@@ -1198,14 +1188,9 @@ impl PageServerHandler {
            .start_timer(metrics::SmgrQueryType::GetSlruSegment, ctx);

        let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(
-            timeline,
-            req.request_lsn,
-            req.not_modified_since,
-            &latest_gc_cutoff_lsn,
-            ctx,
-        )
-        .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;

        let kind = SlruKind::from_repr(req.kind)
            .ok_or(PageStreamError::BadRequest("invalid SLRU kind".into()))?;
@@ -1216,10 +1201,6 @@ impl PageServerHandler {
        ))
    }

-    /// Note on "fullbackup":
-    /// Full basebackups should only be used for debugging purposes.
-    /// Originally, it was introduced to enable breaking storage format changes,
-    /// but that is not applicable anymore.
    #[allow(clippy::too_many_arguments)]
    #[instrument(skip_all, fields(shard_id, ?lsn, ?prev_lsn, %full_backup))]
    async fn handle_basebackup_request<IO>(
@@ -1423,34 +1404,7 @@ where

        let ctx = self.connection_ctx.attached_child();
        debug!("process query {query_string:?}");
-        if query_string.starts_with("pagestream_v2 ") {
-            let (_, params_raw) = query_string.split_at("pagestream_v2 ".len());
-            let params = params_raw.split(' ').collect::<Vec<_>>();
-            if params.len() != 2 {
-                return Err(QueryError::Other(anyhow::anyhow!(
-                    "invalid param number for pagestream command"
-                )));
-            }
-            let tenant_id = TenantId::from_str(params[0])
-                .with_context(|| format!("Failed to parse tenant id from {}", params[0]))?;
-            let timeline_id = TimelineId::from_str(params[1])
-                .with_context(|| format!("Failed to parse timeline id from {}", params[1]))?;
-
-            tracing::Span::current()
-                .record("tenant_id", field::display(tenant_id))
-                .record("timeline_id", field::display(timeline_id));
-
-            self.check_permission(Some(tenant_id))?;
-
-            self.handle_pagerequests(
-                pgb,
-                tenant_id,
-                timeline_id,
-                PagestreamProtocolVersion::V2,
-                ctx,
-            )
-            .await?;
-        } else if query_string.starts_with("pagestream ") {
+        if query_string.starts_with("pagestream ") {
            let (_, params_raw) = query_string.split_at("pagestream ".len());
            let params = params_raw.split(' ').collect::<Vec<_>>();
            if params.len() != 2 {
@@ -1469,14 +1423,8 @@ where

            self.check_permission(Some(tenant_id))?;

-            self.handle_pagerequests(
-                pgb,
-                tenant_id,
-                timeline_id,
-                PagestreamProtocolVersion::V1,
-                ctx,
-            )
-            .await?;
+            self.handle_pagerequests(pgb, tenant_id, timeline_id, ctx)
+                .await?;
        } else if query_string.starts_with("basebackup ") {
            let (_, params_raw) = query_string.split_at("basebackup ".len());
            let params = params_raw.split_whitespace().collect::<Vec<_>>();
--- a/pageserver/src/pgdatadir_mapping.rs
+++ b/pageserver/src/pgdatadir_mapping.rs
@@ -9,7 +9,6 @@
 use super::tenant::{PageReconstructError, Timeline};
 use crate::context::RequestContext;
 use crate::keyspace::{KeySpace, KeySpaceAccum};
-use crate::metrics::WAL_INGEST;
 use crate::repository::*;
 use crate::span::debug_assert_current_span_has_tenant_and_timeline_id_no_shard_id;
 use crate::walrecord::NeonWalRecord;
@@ -176,6 +175,7 @@ impl Timeline {
        tag: RelTag,
        blknum: BlockNumber,
        version: Version<'_>,
+        latest: bool,
        ctx: &RequestContext,
    ) -> Result<Bytes, PageReconstructError> {
        if tag.relnode == 0 {
@@ -184,7 +184,7 @@ impl Timeline {
            ));
        }

-        let nblocks = self.get_rel_size(tag, version, ctx).await?;
+        let nblocks = self.get_rel_size(tag, version, latest, ctx).await?;
        if blknum >= nblocks {
            debug!(
                "read beyond EOF at {} blk {} at {}, size is {}: returning all-zeros page",
@@ -206,6 +206,7 @@ impl Timeline {
        spcnode: Oid,
        dbnode: Oid,
        version: Version<'_>,
+        latest: bool,
        ctx: &RequestContext,
    ) -> Result<usize, PageReconstructError> {
        let mut total_blocks = 0;
@@ -213,7 +214,7 @@ impl Timeline {
        let rels = self.list_rels(spcnode, dbnode, version, ctx).await?;

        for rel in rels {
-            let n_blocks = self.get_rel_size(rel, version, ctx).await?;
+            let n_blocks = self.get_rel_size(rel, version, latest, ctx).await?;
            total_blocks += n_blocks as usize;
        }
        Ok(total_blocks)
@@ -224,6 +225,7 @@ impl Timeline {
        &self,
        tag: RelTag,
        version: Version<'_>,
+        latest: bool,
        ctx: &RequestContext,
    ) -> Result<BlockNumber, PageReconstructError> {
        if tag.relnode == 0 {
@@ -237,7 +239,7 @@ impl Timeline {
        }

        if (tag.forknum == FSM_FORKNUM || tag.forknum == VISIBILITYMAP_FORKNUM)
-            && !self.get_rel_exists(tag, version, ctx).await?
+            && !self.get_rel_exists(tag, version, latest, ctx).await?
        {
            // FIXME: Postgres sometimes calls smgrcreate() to create
            // FSM, and smgrnblocks() on it immediately afterwards,
@@ -250,8 +252,16 @@ impl Timeline {
        let mut buf = version.get(self, key, ctx).await?;
        let nblocks = buf.get_u32_le();

-        self.update_cached_rel_size(tag, version.get_lsn(), nblocks);
-
+        if latest {
+            // Update relation size cache only if "latest" flag is set.
+            // This flag is set by compute when it is working with most recent version of relation.
+            // Typically master compute node always set latest=true.
+            // Please notice, that even if compute node "by mistake" specifies old LSN but set
+            // latest=true, then it can not cause cache corruption, because with latest=true
+            // pageserver choose max(request_lsn, last_written_lsn) and so cached value will be
+            // associated with most recent value of LSN.
+            self.update_cached_rel_size(tag, version.get_lsn(), nblocks);
+        }
        Ok(nblocks)
    }

@@ -260,6 +270,7 @@ impl Timeline {
        &self,
        tag: RelTag,
        version: Version<'_>,
+        _latest: bool,
        ctx: &RequestContext,
    ) -> Result<bool, PageReconstructError> {
        if tag.relnode == 0 {
@@ -455,12 +466,6 @@ impl Timeline {
                // Didn't find any commit timestamps smaller than the request
                Ok(LsnForTimestamp::Past(min_lsn))
            }
-            (true, _) if commit_lsn < min_lsn => {
-                // the search above did set found_smaller to true but it never increased the lsn.
-                // Then, low is still the old min_lsn, and the subtraction above gave a value
-                // below the min_lsn. We should never do that.
-                Ok(LsnForTimestamp::Past(min_lsn))
-            }
            (true, false) => {
                // Only found commits with timestamps smaller than the request.
                // It's still a valid case for branch creation, return it.
@@ -812,7 +817,7 @@ impl Timeline {
    /// Get cached size of relation if it not updated after specified LSN
    pub fn get_cached_rel_size(&self, tag: &RelTag, lsn: Lsn) -> Option<BlockNumber> {
        let rel_size_cache = self.rel_size_cache.read().unwrap();
-        if let Some((cached_lsn, nblocks)) = rel_size_cache.map.get(tag) {
+        if let Some((cached_lsn, nblocks)) = rel_size_cache.get(tag) {
            if lsn >= *cached_lsn {
                return Some(*nblocks);
            }
@@ -823,16 +828,7 @@ impl Timeline {
    /// Update cached relation size if there is no more recent update
    pub fn update_cached_rel_size(&self, tag: RelTag, lsn: Lsn, nblocks: BlockNumber) {
        let mut rel_size_cache = self.rel_size_cache.write().unwrap();
-
-        if lsn < rel_size_cache.complete_as_of {
-            // Do not cache old values. It's safe to cache the size on read, as long as
-            // the read was at an LSN since we started the WAL ingestion. Reasoning: we
-            // never evict values from the cache, so if the relation size changed after
-            // 'lsn', the new value is already in the cache.
-            return;
-        }
-
-        match rel_size_cache.map.entry(tag) {
+        match rel_size_cache.entry(tag) {
            hash_map::Entry::Occupied(mut entry) => {
                let cached_lsn = entry.get_mut();
                if lsn >= cached_lsn.0 {
@@ -848,13 +844,13 @@ impl Timeline {
    /// Store cached relation size
    pub fn set_cached_rel_size(&self, tag: RelTag, lsn: Lsn, nblocks: BlockNumber) {
        let mut rel_size_cache = self.rel_size_cache.write().unwrap();
-        rel_size_cache.map.insert(tag, (lsn, nblocks));
+        rel_size_cache.insert(tag, (lsn, nblocks));
    }

    /// Remove cached relation size
    pub fn remove_cached_rel_size(&self, tag: &RelTag) {
        let mut rel_size_cache = self.rel_size_cache.write().unwrap();
-        rel_size_cache.map.remove(tag);
+        rel_size_cache.remove(tag);
    }
 }

@@ -1092,7 +1088,7 @@ impl<'a> DatadirModification<'a> {
    ) -> anyhow::Result<()> {
        let total_blocks = self
            .tline
-            .get_db_size(spcnode, dbnode, Version::Modified(self), ctx)
+            .get_db_size(spcnode, dbnode, Version::Modified(self), true, ctx)
            .await?;

        // Remove entry from dbdir
@@ -1191,7 +1187,7 @@ impl<'a> DatadirModification<'a> {
        anyhow::ensure!(rel.relnode != 0, RelationError::InvalidRelnode);
        if self
            .tline
-            .get_rel_exists(rel, Version::Modified(self), ctx)
+            .get_rel_exists(rel, Version::Modified(self), true, ctx)
            .await?
        {
            let size_key = rel_size_to_key(rel);
@@ -1405,7 +1401,7 @@ impl<'a> DatadirModification<'a> {
        let n_files;
        let mut aux_files = self.tline.aux_files.lock().await;
        if let Some(mut dir) = aux_files.dir.take() {
-            // We already updated aux files in `self`: emit a delta and update our latest value.
+            // We already updated aux files in `self`: emit a delta and update our latest value
            dir.upsert(file_path.clone(), content.clone());
            n_files = dir.files.len();
            if aux_files.n_deltas == MAX_AUX_FILE_DELTAS {
@@ -1450,14 +1446,10 @@ impl<'a> DatadirModification<'a> {
                    // reset the map.
                    return Err(e.into());
                }
-                // Note: we added missing key error variant in https://github.com/neondatabase/neon/pull/7393 but
-                // the original code assumes all other errors are missing keys. Therefore, we keep the code path
-                // the same for now, though in theory, we should only match the `MissingKey` variant.
-                Err(
-                    PageReconstructError::Other(_)
-                    | PageReconstructError::WalRedo(_)
-                    | PageReconstructError::MissingKey { .. },
-                ) => {
+                // FIXME: PageReconstructError doesn't have an explicit variant for key-not-found, so
+                // we are assuming that all _other_ possible errors represents a missing key.  If some
+                // other error occurs, we may incorrectly reset the map of aux files.
+                Err(PageReconstructError::Other(_) | PageReconstructError::WalRedo(_)) => {
                    // Key is missing, we must insert an image as the basis for subsequent deltas.

                    let mut dir = AuxFilesDirectory {
@@ -1549,8 +1541,6 @@ impl<'a> DatadirModification<'a> {
    pub async fn commit(&mut self, ctx: &RequestContext) -> anyhow::Result<()> {
        let mut writer = self.tline.writer().await;

-        let timer = WAL_INGEST.time_spent_on_ingest.start_timer();
-
        let pending_nblocks = self.pending_nblocks;
        self.pending_nblocks = 0;

@@ -1590,8 +1580,6 @@ impl<'a> DatadirModification<'a> {
            writer.update_directory_entries_count(kind, count as u64);
        }

-        timer.observe_duration();
-
        Ok(())
    }

--- a/pageserver/src/task_mgr.rs
+++ b/pageserver/src/task_mgr.rs
@@ -361,8 +361,6 @@ pub enum TaskKind {

    DebugTool,

-    EphemeralFilePreWarmPageCache,
-
    #[cfg(test)]
    UnitTest,
 }
--- a/pageserver/src/tenant.rs
+++ b/pageserver/src/tenant.rs
@@ -559,10 +559,9 @@ impl Tenant {
            // By doing what we do here, the index part upload is retried.
            // If control plane retries timeline creation in the meantime, the mgmt API handler
            // for timeline creation will coalesce on the upload we queue here.
-            // FIXME: this branch should be dead code as we no longer write local metadata.
            let rtc = timeline.remote_client.as_ref().unwrap();
            rtc.init_upload_queue_for_empty_remote(&metadata)?;
-            rtc.schedule_index_upload_for_full_metadata_update(&metadata)?;
+            rtc.schedule_index_upload_for_metadata_update(&metadata)?;
        }

        timeline
@@ -888,7 +887,7 @@ impl Tenant {

    #[instrument(skip_all)]
    pub(crate) async fn preload(
-        self: &Arc<Self>,
+        self: &Arc<Tenant>,
        remote_storage: &GenericRemoteStorage,
        cancel: CancellationToken,
    ) -> anyhow::Result<TenantPreload> {
@@ -918,13 +917,9 @@ impl Tenant {

        Ok(TenantPreload {
            deleting,
-            timelines: Self::load_timeline_metadata(
-                self,
-                remote_timeline_ids,
-                remote_storage,
-                cancel,
-            )
-            .await?,
+            timelines: self
+                .load_timeline_metadata(remote_timeline_ids, remote_storage, cancel)
+                .await?,
        })
    }

@@ -2874,23 +2869,20 @@ impl Tenant {
                }
            }

-            let cutoff = timeline
-                .get_last_record_lsn()
-                .checked_sub(horizon)
-                .unwrap_or(Lsn(0));
+            if let Some(cutoff) = timeline.get_last_record_lsn().checked_sub(horizon) {
+                let branchpoints: Vec<Lsn> = all_branchpoints
+                    .range((
+                        Included((timeline_id, Lsn(0))),
+                        Included((timeline_id, Lsn(u64::MAX))),
+                    ))
+                    .map(|&x| x.1)
+                    .collect();
+                timeline
+                    .update_gc_info(branchpoints, cutoff, pitr, cancel, ctx)
+                    .await?;

-            let branchpoints: Vec<Lsn> = all_branchpoints
-                .range((
-                    Included((timeline_id, Lsn(0))),
-                    Included((timeline_id, Lsn(u64::MAX))),
-                ))
-                .map(|&x| x.1)
-                .collect();
-            timeline
-                .update_gc_info(branchpoints, cutoff, pitr, cancel, ctx)
-                .await?;
-
-            gc_timelines.push(timeline);
+                gc_timelines.push(timeline);
+            }
        }
        drop(gc_cs);
        Ok(gc_timelines)
@@ -3035,7 +3027,7 @@ impl Tenant {
        // See also https://github.com/neondatabase/neon/issues/3865
        if let Some(remote_client) = new_timeline.remote_client.as_ref() {
            remote_client
-                .schedule_index_upload_for_full_metadata_update(&metadata)
+                .schedule_index_upload_for_metadata_update(&metadata)
                .context("branch initial metadata upload")?;
        }

@@ -3406,11 +3398,7 @@ impl Tenant {
        // is in progress (which is not a common case).
        //
        // See more for on the issue #2748 condenced out of the initial PR review.
-        let mut shared_cache = tokio::select! {
-            locked = self.cached_logical_sizes.lock() => locked,
-            _ = cancel.cancelled() => anyhow::bail!("cancelled"),
-            _ = self.cancel.cancelled() => anyhow::bail!("tenant is shutting down"),
-        };
+        let mut shared_cache = self.cached_logical_sizes.lock().await;

        size::gather_inputs(
            self,
@@ -3672,7 +3660,6 @@ pub(crate) mod harness {
                image_layer_creation_check_threshold: Some(
                    tenant_conf.image_layer_creation_check_threshold,
                ),
-                switch_to_aux_file_v2: Some(tenant_conf.switch_to_aux_file_v2),
            }
        }
    }
@@ -3871,10 +3858,8 @@ mod tests {
    use crate::DEFAULT_PG_VERSION;
    use bytes::BytesMut;
    use hex_literal::hex;
-    use pageserver_api::key::NON_INHERITED_RANGE;
    use pageserver_api::keyspace::KeySpace;
    use rand::{thread_rng, Rng};
-    use tests::storage_layer::ValuesReconstructState;
    use tests::timeline::{GetVectoredError, ShutdownMode};

    static TEST_KEY: Lazy<Key> =
@@ -4663,9 +4648,7 @@ mod tests {
        for read in reads {
            info!("Doing vectored read on {:?}", read);

-            let vectored_res = tline
-                .get_vectored_impl(read.clone(), reads_lsn, ValuesReconstructState::new(), &ctx)
-                .await;
+            let vectored_res = tline.get_vectored_impl(read.clone(), reads_lsn, &ctx).await;
            tline
                .validate_get_vectored_impl(&vectored_res, read, reads_lsn, &ctx)
                .await;
@@ -4674,67 +4657,6 @@ mod tests {
        Ok(())
    }

-    #[tokio::test]
-    async fn test_get_vectored_aux_files() -> anyhow::Result<()> {
-        let harness = TenantHarness::create("test_get_vectored_aux_files")?;
-
-        let (tenant, ctx) = harness.load().await;
-        let tline = tenant
-            .create_empty_timeline(TIMELINE_ID, Lsn(0), DEFAULT_PG_VERSION, &ctx)
-            .await?;
-        let tline = tline.raw_timeline().unwrap();
-
-        let mut modification = tline.begin_modification(Lsn(0x1000));
-        modification.put_file("foo/bar1", b"content1", &ctx).await?;
-        modification.set_lsn(Lsn(0x1008))?;
-        modification.put_file("foo/bar2", b"content2", &ctx).await?;
-        modification.commit(&ctx).await?;
-
-        let child_timeline_id = TimelineId::generate();
-        tenant
-            .branch_timeline_test(
-                tline,
-                child_timeline_id,
-                Some(tline.get_last_record_lsn()),
-                &ctx,
-            )
-            .await?;
-
-        let child_timeline = tenant
-            .get_timeline(child_timeline_id, true)
-            .expect("Should have the branched timeline");
-
-        let aux_keyspace = KeySpace {
-            ranges: vec![NON_INHERITED_RANGE],
-        };
-        let read_lsn = child_timeline.get_last_record_lsn();
-
-        let vectored_res = child_timeline
-            .get_vectored_impl(
-                aux_keyspace.clone(),
-                read_lsn,
-                ValuesReconstructState::new(),
-                &ctx,
-            )
-            .await;
-
-        child_timeline
-            .validate_get_vectored_impl(&vectored_res, aux_keyspace, read_lsn, &ctx)
-            .await;
-
-        let images = vectored_res?;
-        let mut key = NON_INHERITED_RANGE.start;
-        while key < NON_INHERITED_RANGE.end {
-            assert!(matches!(
-                images[&key],
-                Err(PageReconstructError::MissingKey(_))
-            ));
-            key = key.next();
-        }
-
-        Ok(())
-    }
-
    // Test that vectored get handles layer gaps correctly
    // by advancing into the next ancestor timeline if required.
    //
@@ -4863,12 +4785,7 @@ mod tests {
            ranges: vec![key_near_gap..gap_at_key.next(), key_near_end..current_key],
        };
        let results = child_timeline
-            .get_vectored_impl(
-                read.clone(),
-                current_lsn,
-                ValuesReconstructState::new(),
-                &ctx,
-            )
+            .get_vectored_impl(read.clone(), current_lsn, &ctx)
            .await?;

        for (key, img_res) in results {
@@ -5001,7 +4918,6 @@ mod tests {
                        ranges: vec![child_gap_at_key..child_gap_at_key.next()],
                    },
                    query_lsn,
-                    ValuesReconstructState::new(),
                    &ctx,
                )
                .await;
--- a/pageserver/src/tenant/blob_io.rs
+++ b/pageserver/src/tenant/blob_io.rs
@@ -121,7 +121,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
        self.offset
    }

-    const CAPACITY: usize = if BUFFERED { 64 * 1024 } else { 0 };
+    const CAPACITY: usize = if BUFFERED { PAGE_SZ } else { 0 };

    /// Writes the given buffer directly to the underlying `VirtualFile`.
    /// You need to make sure that the internal buffer is empty, otherwise
--- a/pageserver/src/tenant/config.rs
+++ b/pageserver/src/tenant/config.rs
@@ -369,10 +369,6 @@ pub struct TenantConf {
    // How much WAL must be ingested before checking again whether a new image layer is required.
    // Expresed in multiples of checkpoint distance.
    pub image_layer_creation_check_threshold: u8,
-
-    /// Switch to aux file v2. Switching this flag requires the user has not written any aux file into
-    /// the storage before, and this flag cannot be switched back. Otherwise there will be data corruptions.
-    pub switch_to_aux_file_v2: bool,
 }

 /// Same as TenantConf, but this struct preserves the information about
@@ -468,10 +464,6 @@ pub struct TenantConfOpt {

    #[serde(skip_serializing_if = "Option::is_none")]
    pub image_layer_creation_check_threshold: Option<u8>,
-
-    #[serde(skip_serializing_if = "Option::is_none")]
-    #[serde(default)]
-    pub switch_to_aux_file_v2: Option<bool>,
 }

 impl TenantConfOpt {
@@ -529,9 +521,6 @@ impl TenantConfOpt {
            image_layer_creation_check_threshold: self
                .image_layer_creation_check_threshold
                .unwrap_or(global_conf.image_layer_creation_check_threshold),
-            switch_to_aux_file_v2: self
-                .switch_to_aux_file_v2
-                .unwrap_or(global_conf.switch_to_aux_file_v2),
        }
    }
 }
@@ -573,7 +562,6 @@ impl Default for TenantConf {
            lazy_slru_download: false,
            timeline_get_throttle: crate::tenant::throttle::Config::disabled(),
            image_layer_creation_check_threshold: DEFAULT_IMAGE_LAYER_CREATION_CHECK_THRESHOLD,
-            switch_to_aux_file_v2: false,
        }
    }
 }
@@ -648,7 +636,6 @@ impl From<TenantConfOpt> for models::TenantConfig {
            lazy_slru_download: value.lazy_slru_download,
            timeline_get_throttle: value.timeline_get_throttle.map(ThrottleConfig::from),
            image_layer_creation_check_threshold: value.image_layer_creation_check_threshold,
-            switch_to_aux_file_v2: value.switch_to_aux_file_v2,
        }
    }
 }
--- a/pageserver/src/tenant/ephemeral_file.rs
+++ b/pageserver/src/tenant/ephemeral_file.rs
@@ -3,26 +3,36 @@

 use crate::config::PageServerConf;
 use crate::context::RequestContext;
-use crate::page_cache;
+use crate::page_cache::{self, PAGE_SZ};
 use crate::tenant::block_io::{BlockCursor, BlockLease, BlockReader};
 use crate::virtual_file::{self, VirtualFile};
+use bytes::BytesMut;
 use camino::Utf8PathBuf;
 use pageserver_api::shard::TenantShardId;
+use std::cmp::min;

-use std::io;
+use std::io::{self, ErrorKind};
+use std::ops::DerefMut;
 use std::sync::atomic::AtomicU64;
+use tracing::*;
 use utils::id::TimelineId;

 pub struct EphemeralFile {
+    page_cache_file_id: page_cache::FileId,
+
    _tenant_shard_id: TenantShardId,
    _timeline_id: TimelineId,
-
-    rw: page_caching::RW,
+    file: VirtualFile,
+    len: u64,
+    /// An ephemeral file is append-only.
+    /// We keep the last page, which can still be modified, in [`Self::mutable_tail`].
+    /// The other pages, which can no longer be modified, are accessed through the page cache.
+    ///
+    /// None <=> IO is ongoing.
+    /// Size is fixed to PAGE_SZ at creation time and must not be changed.
+    mutable_tail: Option<BytesMut>,
 }

-mod page_caching;
-mod zero_padded_read_write;
-
 impl EphemeralFile {
    pub async fn create(
        conf: &PageServerConf,
@@ -49,18 +59,21 @@ impl EphemeralFile {
        .await?;

        Ok(EphemeralFile {
+            page_cache_file_id: page_cache::next_file_id(),
            _tenant_shard_id: tenant_shard_id,
            _timeline_id: timeline_id,
-            rw: page_caching::RW::new(file),
+            file,
+            len: 0,
+            mutable_tail: Some(BytesMut::zeroed(PAGE_SZ)),
        })
    }

    pub(crate) fn len(&self) -> u64 {
-        self.rw.bytes_written()
+        self.len
    }

-    pub(crate) fn page_cache_file_id(&self) -> page_cache::FileId {
-        self.rw.page_cache_file_id()
+    pub(crate) fn id(&self) -> page_cache::FileId {
+        self.page_cache_file_id
    }

    pub(crate) async fn read_blk(
@@ -68,30 +81,182 @@ impl EphemeralFile {
        blknum: u32,
        ctx: &RequestContext,
    ) -> Result<BlockLease, io::Error> {
-        self.rw.read_blk(blknum, ctx).await
+        let flushed_blknums = 0..self.len / PAGE_SZ as u64;
+        if flushed_blknums.contains(&(blknum as u64)) {
+            let cache = page_cache::get();
+            match cache
+                .read_immutable_buf(self.page_cache_file_id, blknum, ctx)
+                .await
+                .map_err(|e| {
+                    std::io::Error::new(
+                        std::io::ErrorKind::Other,
+                        // order path before error because error is anyhow::Error => might have many contexts
+                        format!(
+                            "ephemeral file: read immutable page #{}: {}: {:#}",
+                            blknum, self.file.path, e,
+                        ),
+                    )
+                })? {
+                page_cache::ReadBufResult::Found(guard) => {
+                    return Ok(BlockLease::PageReadGuard(guard))
+                }
+                page_cache::ReadBufResult::NotFound(write_guard) => {
+                    let write_guard = self
+                        .file
+                        .read_exact_at_page(write_guard, blknum as u64 * PAGE_SZ as u64)
+                        .await?;
+                    let read_guard = write_guard.mark_valid();
+                    return Ok(BlockLease::PageReadGuard(read_guard));
+                }
+            };
+        } else {
+            debug_assert_eq!(blknum as u64, self.len / PAGE_SZ as u64);
+            Ok(BlockLease::EphemeralFileMutableTail(
+                self.mutable_tail
+                    .as_deref()
+                    .expect("we're not doing IO, it must be Some()")
+                    .try_into()
+                    .expect("we ensure that it's always PAGE_SZ"),
+            ))
+        }
    }

    pub(crate) async fn write_blob(
        &mut self,
        srcbuf: &[u8],
-        _ctx: &RequestContext,
+        ctx: &RequestContext,
    ) -> Result<u64, io::Error> {
-        let pos = self.rw.bytes_written();
+        struct Writer<'a> {
+            ephemeral_file: &'a mut EphemeralFile,
+            /// The block to which the next [`push_bytes`] will write.
+            blknum: u32,
+            /// The offset inside the block identified by [`blknum`] to which [`push_bytes`] will write.
+            off: usize,
+        }
+        impl<'a> Writer<'a> {
+            fn new(ephemeral_file: &'a mut EphemeralFile) -> io::Result<Writer<'a>> {
+                Ok(Writer {
+                    blknum: (ephemeral_file.len / PAGE_SZ as u64) as u32,
+                    off: (ephemeral_file.len % PAGE_SZ as u64) as usize,
+                    ephemeral_file,
+                })
+            }
+            #[inline(always)]
+            async fn push_bytes(
+                &mut self,
+                src: &[u8],
+                ctx: &RequestContext,
+            ) -> Result<(), io::Error> {
+                let mut src_remaining = src;
+                while !src_remaining.is_empty() {
+                    let dst_remaining = &mut self
+                        .ephemeral_file
+                        .mutable_tail
+                        .as_deref_mut()
+                        .expect("IO is not yet ongoing")[self.off..];
+                    let n = min(dst_remaining.len(), src_remaining.len());
+                    dst_remaining[..n].copy_from_slice(&src_remaining[..n]);
+                    self.off += n;
+                    src_remaining = &src_remaining[n..];
+                    if self.off == PAGE_SZ {
+                        let mutable_tail = std::mem::take(&mut self.ephemeral_file.mutable_tail)
+                            .expect("IO is not yet ongoing");
+                        let (mutable_tail, res) = self
+                            .ephemeral_file
+                            .file
+                            .write_all_at(mutable_tail, self.blknum as u64 * PAGE_SZ as u64)
+                            .await;
+                        // TODO: If we panic before we can put the mutable_tail back, subsequent calls will fail.
+                        // I.e., the IO isn't retryable if we panic.
+                        self.ephemeral_file.mutable_tail = Some(mutable_tail);
+                        match res {
+                            Ok(_) => {
+                                // Pre-warm the page cache with what we just wrote.
+                                // This isn't necessary for coherency/correctness, but it's how we've always done it.
+                                let cache = page_cache::get();
+                                match cache
+                                    .read_immutable_buf(
+                                        self.ephemeral_file.page_cache_file_id,
+                                        self.blknum,
+                                        ctx,
+                                    )
+                                    .await
+                                {
+                                    Ok(page_cache::ReadBufResult::Found(_guard)) => {
+                                        // This function takes &mut self, so, it shouldn't be possible to reach this point.
+                                        unreachable!("we just wrote blknum {} and this function takes &mut self, so, no concurrent read_blk is possible", self.blknum);
+                                    }
+                                    Ok(page_cache::ReadBufResult::NotFound(mut write_guard)) => {
+                                        let buf: &mut [u8] = write_guard.deref_mut();
+                                        debug_assert_eq!(buf.len(), PAGE_SZ);
+                                        buf.copy_from_slice(
+                                            self.ephemeral_file
+                                                .mutable_tail
+                                                .as_deref()
+                                                .expect("IO is not ongoing"),
+                                        );
+                                        let _ = write_guard.mark_valid();
+                                        // pre-warm successful
+                                    }
+                                    Err(e) => {
+                                        error!("ephemeral_file write_blob failed to get immutable buf to pre-warm page cache: {e:?}");
+                                        // fail gracefully, it's not the end of the world if we can't pre-warm the cache here
+                                    }
+                                }
+                                // Zero the buffer for re-use.
+                                // Zeroing is critical for correcntess because the write_blob code below
+                                // and similarly read_blk expect zeroed pages.
+                                self.ephemeral_file
+                                    .mutable_tail
+                                    .as_deref_mut()
+                                    .expect("IO is not ongoing")
+                                    .fill(0);
+                                // This block is done, move to next one.
+                                self.blknum += 1;
+                                self.off = 0;
+                            }
+                            Err(e) => {
+                                return Err(std::io::Error::new(
+                                    ErrorKind::Other,
+                                    // order error before path because path is long and error is short
+                                    format!(
+                                        "ephemeral_file: write_blob: write-back full tail blk #{}: {:#}: {}",
+                                        self.blknum,
+                                        e,
+                                        self.ephemeral_file.file.path,
+                                    ),
+                                ));
+                            }
+                        }
+                    }
+                }
+                Ok(())
+            }
+        }
+
+        let pos = self.len;
+        let mut writer = Writer::new(self)?;

        // Write the length field
        if srcbuf.len() < 0x80 {
            // short one-byte length header
            let len_buf = [srcbuf.len() as u8];
-
-            self.rw.write_all_borrowed(&len_buf).await?;
+            writer.push_bytes(&len_buf, ctx).await?;
        } else {
            let mut len_buf = u32::to_be_bytes(srcbuf.len() as u32);
            len_buf[0] |= 0x80;
-            self.rw.write_all_borrowed(&len_buf).await?;
+            writer.push_bytes(&len_buf, ctx).await?;
        }

        // Write the payload
-        self.rw.write_all_borrowed(srcbuf).await?;
+        writer.push_bytes(srcbuf, ctx).await?;
+
+        if srcbuf.len() < 0x80 {
+            self.len += 1;
+        } else {
+            self.len += 4;
+        }
+        self.len += srcbuf.len() as u64;

        Ok(pos)
    }
@@ -106,6 +271,28 @@ pub fn is_ephemeral_file(filename: &str) -> bool {
    }
 }

+impl Drop for EphemeralFile {
+    fn drop(&mut self) {
+        // There might still be pages in the [`crate::page_cache`] for this file.
+        // We leave them there, [`crate::page_cache::PageCache::find_victim`] will evict them when needed.
+
+        // unlink the file
+        let res = std::fs::remove_file(&self.file.path);
+        if let Err(e) = res {
+            if e.kind() != std::io::ErrorKind::NotFound {
+                // just never log the not found errors, we cannot do anything for them; on detach
+                // the tenant directory is already gone.
+                //
+                // not found files might also be related to https://github.com/neondatabase/neon/issues/2442
+                error!(
+                    "could not remove ephemeral file '{}': {}",
+                    self.file.path, e
+                );
+            }
+        }
+    }
+}
+
 impl BlockReader for EphemeralFile {
    fn block_cursor(&self) -> super::block_io::BlockCursor<'_> {
        BlockCursor::new(super::block_io::BlockReaderRef::EphemeralFile(self))
--- a/pageserver/src/tenant/ephemeral_file/page_caching.rs
+++ b/pageserver/src/tenant/ephemeral_file/page_caching.rs
@@ -1,218 +0,0 @@
-//! Wrapper around [`super::zero_padded_read_write::RW`] that uses the
-//! [`crate::page_cache`] to serve reads that need to go to the underlying [`VirtualFile`].
-
-use crate::context::RequestContext;
-use crate::page_cache::{self, PAGE_SZ};
-use crate::tenant::block_io::BlockLease;
-use crate::virtual_file::VirtualFile;
-
-use once_cell::sync::Lazy;
-use std::io::{self, ErrorKind};
-use tokio_epoll_uring::BoundedBuf;
-use tracing::*;
-
-use super::zero_padded_read_write;
-
-/// See module-level comment.
-pub struct RW {
-    page_cache_file_id: page_cache::FileId,
-    rw: super::zero_padded_read_write::RW<PreWarmingWriter>,
-}
-
-impl RW {
-    pub fn new(file: VirtualFile) -> Self {
-        let page_cache_file_id = page_cache::next_file_id();
-        Self {
-            page_cache_file_id,
-            rw: super::zero_padded_read_write::RW::new(PreWarmingWriter::new(
-                page_cache_file_id,
-                file,
-            )),
-        }
-    }
-
-    pub fn page_cache_file_id(&self) -> page_cache::FileId {
-        self.page_cache_file_id
-    }
-
-    pub(crate) async fn write_all_borrowed(&mut self, srcbuf: &[u8]) -> Result<usize, io::Error> {
-        // It doesn't make sense to proactively fill the page cache on the Pageserver write path
-        // because Compute is unlikely to access recently written data.
-        self.rw.write_all_borrowed(srcbuf).await
-    }
-
-    pub(crate) fn bytes_written(&self) -> u64 {
-        self.rw.bytes_written()
-    }
-
-    pub(crate) async fn read_blk(
-        &self,
-        blknum: u32,
-        ctx: &RequestContext,
-    ) -> Result<BlockLease, io::Error> {
-        match self.rw.read_blk(blknum).await? {
-            zero_padded_read_write::ReadResult::NeedsReadFromWriter { writer } => {
-                let cache = page_cache::get();
-                match cache
-                    .read_immutable_buf(self.page_cache_file_id, blknum, ctx)
-                    .await
-                    .map_err(|e| {
-                        std::io::Error::new(
-                            std::io::ErrorKind::Other,
-                            // order path before error because error is anyhow::Error => might have many contexts
-                            format!(
-                                "ephemeral file: read immutable page #{}: {}: {:#}",
-                                blknum,
-                                self.rw.as_writer().file.path,
-                                e,
-                            ),
-                        )
-                    })? {
-                    page_cache::ReadBufResult::Found(guard) => {
-                        return Ok(BlockLease::PageReadGuard(guard))
-                    }
-                    page_cache::ReadBufResult::NotFound(write_guard) => {
-                        let write_guard = writer
-                            .file
-                            .read_exact_at_page(write_guard, blknum as u64 * PAGE_SZ as u64)
-                            .await?;
-                        let read_guard = write_guard.mark_valid();
-                        return Ok(BlockLease::PageReadGuard(read_guard));
-                    }
-                }
-            }
-            zero_padded_read_write::ReadResult::ServedFromZeroPaddedMutableTail { buffer } => {
-                Ok(BlockLease::EphemeralFileMutableTail(buffer))
-            }
-        }
-    }
-}
-
-impl Drop for RW {
-    fn drop(&mut self) {
-        // There might still be pages in the [`crate::page_cache`] for this file.
-        // We leave them there, [`crate::page_cache::PageCache::find_victim`] will evict them when needed.
-
-        // unlink the file
-        let res = std::fs::remove_file(&self.rw.as_writer().file.path);
-        if let Err(e) = res {
-            if e.kind() != std::io::ErrorKind::NotFound {
-                // just never log the not found errors, we cannot do anything for them; on detach
-                // the tenant directory is already gone.
-                //
-                // not found files might also be related to https://github.com/neondatabase/neon/issues/2442
-                error!(
-                    "could not remove ephemeral file '{}': {}",
-                    self.rw.as_writer().file.path,
-                    e
-                );
-            }
-        }
-    }
-}
-
-struct PreWarmingWriter {
-    nwritten_blocks: u32,
-    page_cache_file_id: page_cache::FileId,
-    file: VirtualFile,
-}
-
-impl PreWarmingWriter {
-    fn new(page_cache_file_id: page_cache::FileId, file: VirtualFile) -> Self {
-        Self {
-            nwritten_blocks: 0,
-            page_cache_file_id,
-            file,
-        }
-    }
-}
-
-impl crate::virtual_file::owned_buffers_io::write::OwnedAsyncWriter for PreWarmingWriter {
-    async fn write_all<
-        B: tokio_epoll_uring::BoundedBuf<Buf = Buf>,
-        Buf: tokio_epoll_uring::IoBuf + Send,
-    >(
-        &mut self,
-        buf: B,
-    ) -> std::io::Result<(usize, B::Buf)> {
-        let buf = buf.slice(..);
-        let saved_bounds = buf.bounds(); // save for reconstructing the Slice from iobuf after the IO is done
-        let check_bounds_stuff_works = if cfg!(test) && cfg!(debug_assertions) {
-            Some(buf.to_vec())
-        } else {
-            None
-        };
-        let buflen = buf.len();
-        assert_eq!(
-            buflen % PAGE_SZ,
-            0,
-            "{buflen} ; we know TAIL_SZ is a PAGE_SZ multiple, and write_buffered_borrowed is used"
-        );
-
-        // Do the IO.
-        let iobuf = match self.file.write_all(buf).await {
-            (iobuf, Ok(nwritten)) => {
-                assert_eq!(nwritten, buflen);
-                iobuf
-            }
-            (_, Err(e)) => {
-                return Err(std::io::Error::new(
-                    ErrorKind::Other,
-                    // order error before path because path is long and error is short
-                    format!(
-                        "ephemeral_file: write_blob: write-back tail self.nwritten_blocks={}, buflen={}, {:#}: {}",
-                        self.nwritten_blocks, buflen, e, self.file.path,
-                    ),
-                ));
-            }
-        };
-
-        // Reconstruct the Slice (the write path consumed the Slice and returned us the underlying IoBuf)
-        let buf = tokio_epoll_uring::Slice::from_buf_bounds(iobuf, saved_bounds);
-        if let Some(check_bounds_stuff_works) = check_bounds_stuff_works {
-            assert_eq!(&check_bounds_stuff_works, &*buf);
-        }
-
-        // Pre-warm page cache with the contents.
-        // At least in isolated bulk ingest benchmarks (test_bulk_insert.py), the pre-warming
-        // benefits the code that writes InMemoryLayer=>L0 layers.
-        let nblocks = buflen / PAGE_SZ;
-        let nblocks32 = u32::try_from(nblocks).unwrap();
-        let cache = page_cache::get();
-        static CTX: Lazy<RequestContext> = Lazy::new(|| {
-            RequestContext::new(
-                crate::task_mgr::TaskKind::EphemeralFilePreWarmPageCache,
-                crate::context::DownloadBehavior::Error,
-            )
-        });
-        for blknum_in_buffer in 0..nblocks {
-            let blk_in_buffer = &buf[blknum_in_buffer * PAGE_SZ..(blknum_in_buffer + 1) * PAGE_SZ];
-            let blknum = self
-                .nwritten_blocks
-                .checked_add(blknum_in_buffer as u32)
-                .unwrap();
-            match cache
-                .read_immutable_buf(self.page_cache_file_id, blknum, &CTX)
-                .await
-            {
-                Err(e) => {
-                    error!("ephemeral_file write_blob failed to get immutable buf to pre-warm page cache: {e:?}");
-                    // fail gracefully, it's not the end of the world if we can't pre-warm the cache here
-                }
-                Ok(v) => match v {
-                    page_cache::ReadBufResult::Found(_guard) => {
-                        // This function takes &mut self, so, it shouldn't be possible to reach this point.
-                        unreachable!("we just wrote block {blknum} to the VirtualFile, which is owned by Self, \
-                                      and this function takes &mut self, so, no concurrent read_blk is possible");
-                    }
-                    page_cache::ReadBufResult::NotFound(mut write_guard) => {
-                        write_guard.copy_from_slice(blk_in_buffer);
-                        let _ = write_guard.mark_valid();
-                    }
-                },
-            }
-        }
-        self.nwritten_blocks = self.nwritten_blocks.checked_add(nblocks32).unwrap();
-        Ok((buflen, buf.into_inner()))
-    }
-}
--- a/pageserver/src/tenant/ephemeral_file/zero_padded_read_write.rs
+++ b/pageserver/src/tenant/ephemeral_file/zero_padded_read_write.rs
@@ -1,125 +0,0 @@
-//! The heart of how [`super::EphemeralFile`] does its reads and writes.
-//!
-//! # Writes
-//!
-//! [`super::EphemeralFile`] writes small, borrowed buffers using [`RW::write_all_borrowed`].
-//! The [`RW`] batches these into [`TAIL_SZ`] bigger writes, using [`owned_buffers_io::write::BufferedWriter`].
-//!
-//! # Reads
-//!
-//! [`super::EphemeralFile`] always reads full [`PAGE_SZ`]ed blocks using [`RW::read_blk`].
-//!
-//! The [`RW`] serves these reads either from the buffered writer's in-memory buffer
-//! or redirects the caller to read from the underlying [`OwnedAsyncWriter`]
-//! if the read is for the prefix that has already been flushed.
-//!
-//! # Current Usage
-//!
-//! The current user of this module is [`super::page_caching::RW`].
-
-mod zero_padded;
-
-use crate::{
-    page_cache::PAGE_SZ,
-    virtual_file::owned_buffers_io::{
-        self,
-        write::{Buffer, OwnedAsyncWriter},
-    },
-};
-
-const TAIL_SZ: usize = 64 * 1024;
-
-/// See module-level comment.
-pub struct RW<W: OwnedAsyncWriter> {
-    buffered_writer: owned_buffers_io::write::BufferedWriter<
-        zero_padded::Buffer<TAIL_SZ>,
-        owned_buffers_io::util::size_tracking_writer::Writer<W>,
-    >,
-}
-
-pub enum ReadResult<'a, W> {
-    NeedsReadFromWriter { writer: &'a W },
-    ServedFromZeroPaddedMutableTail { buffer: &'a [u8; PAGE_SZ] },
-}
-
-impl<W> RW<W>
-where
-    W: OwnedAsyncWriter,
-{
-    pub fn new(writer: W) -> Self {
-        let bytes_flushed_tracker =
-            owned_buffers_io::util::size_tracking_writer::Writer::new(writer);
-        let buffered_writer = owned_buffers_io::write::BufferedWriter::new(
-            bytes_flushed_tracker,
-            zero_padded::Buffer::default(),
-        );
-        Self { buffered_writer }
-    }
-
-    pub(crate) fn as_writer(&self) -> &W {
-        self.buffered_writer.as_inner().as_inner()
-    }
-
-    pub async fn write_all_borrowed(&mut self, buf: &[u8]) -> std::io::Result<usize> {
-        self.buffered_writer.write_buffered_borrowed(buf).await
-    }
-
-    pub fn bytes_written(&self) -> u64 {
-        let flushed_offset = self.buffered_writer.as_inner().bytes_written();
-        let buffer: &zero_padded::Buffer<TAIL_SZ> = self.buffered_writer.inspect_buffer();
-        flushed_offset + u64::try_from(buffer.pending()).unwrap()
-    }
-
-    pub(crate) async fn read_blk(&self, blknum: u32) -> Result<ReadResult<'_, W>, std::io::Error> {
-        let flushed_offset = self.buffered_writer.as_inner().bytes_written();
-        let buffer: &zero_padded::Buffer<TAIL_SZ> = self.buffered_writer.inspect_buffer();
-        let buffered_offset = flushed_offset + u64::try_from(buffer.pending()).unwrap();
-        let read_offset = (blknum as u64) * (PAGE_SZ as u64);
-
-        // The trailing page ("block") might only be partially filled,
-        // yet the blob_io code relies on us to return a full PAGE_SZed slice anyway.
-        // Moreover, it has to be zero-padded, because when we still had
-        // a write-back page cache, it provided pre-zeroed pages, and blob_io came to rely on it.
-        // DeltaLayer probably has the same issue, not sure why it needs no special treatment.
-        // => check here that the read doesn't go beyond this potentially trailing
-        // => the zero-padding is done in the `else` branch below
-        let blocks_written = if buffered_offset % (PAGE_SZ as u64) == 0 {
-            buffered_offset / (PAGE_SZ as u64)
-        } else {
-            (buffered_offset / (PAGE_SZ as u64)) + 1
-        };
-        if (blknum as u64) >= blocks_written {
-            return Err(std::io::Error::new(std::io::ErrorKind::Other, anyhow::anyhow!("read past end of ephemeral_file: read=0x{read_offset:x} buffered=0x{buffered_offset:x} flushed=0x{flushed_offset}")));
-        }
-
-        // assertions for the `if-else` below
-        assert_eq!(
-            flushed_offset % (TAIL_SZ as u64), 0,
-            "we only use write_buffered_borrowed to write to the buffered writer, so it's guaranteed that flushes happen buffer.cap()-sized chunks"
-        );
-        assert_eq!(
-            flushed_offset % (PAGE_SZ as u64),
-            0,
-            "the logic below can't handle if the page is spread across the flushed part and the buffer"
-        );
-
-        if read_offset < flushed_offset {
-            assert!(read_offset + (PAGE_SZ as u64) <= flushed_offset);
-            Ok(ReadResult::NeedsReadFromWriter {
-                writer: self.as_writer(),
-            })
-        } else {
-            let read_offset_in_buffer = read_offset
-                .checked_sub(flushed_offset)
-                .expect("would have taken `if` branch instead of this one");
-            let read_offset_in_buffer = usize::try_from(read_offset_in_buffer).unwrap();
-            let zero_padded_slice = buffer.as_zero_padded_slice();
-            let page = &zero_padded_slice[read_offset_in_buffer..(read_offset_in_buffer + PAGE_SZ)];
-            Ok(ReadResult::ServedFromZeroPaddedMutableTail {
-                buffer: page
-                    .try_into()
-                    .expect("the slice above got it as page-size slice"),
-            })
-        }
-    }
-}
--- a/pageserver/src/tenant/ephemeral_file/zero_padded_read_write/zero_padded.rs
+++ b/pageserver/src/tenant/ephemeral_file/zero_padded_read_write/zero_padded.rs
@@ -1,108 +0,0 @@
-//! A [`crate::virtual_file::owned_buffers_io::write::Buffer`] whose
-//! unwritten range is guaranteed to be zero-initialized.
-//! This is used by [`crate::tenant::ephemeral_file::zero_padded_read_write::RW::read_blk`]
-//! to serve page-sized reads of the trailing page when the trailing page has only been partially filled.
-
-use std::mem::MaybeUninit;
-
-/// See module-level comment.
-pub struct Buffer<const N: usize> {
-    allocation: Box<[u8; N]>,
-    written: usize,
-}
-
-impl<const N: usize> Default for Buffer<N> {
-    fn default() -> Self {
-        Self {
-            allocation: Box::new(
-                // SAFETY: zeroed memory is a valid [u8; N]
-                unsafe { MaybeUninit::zeroed().assume_init() },
-            ),
-            written: 0,
-        }
-    }
-}
-
-impl<const N: usize> Buffer<N> {
-    #[inline(always)]
-    fn invariants(&self) {
-        // don't check by default, unoptimized is too expensive even for debug mode
-        if false {
-            debug_assert!(self.written <= N, "{}", self.written);
-            debug_assert!(self.allocation[self.written..N].iter().all(|v| *v == 0));
-        }
-    }
-
-    pub fn as_zero_padded_slice(&self) -> &[u8; N] {
-        &self.allocation
-    }
-}
-
-impl<const N: usize> crate::virtual_file::owned_buffers_io::write::Buffer for Buffer<N> {
-    type IoBuf = Self;
-
-    fn cap(&self) -> usize {
-        self.allocation.len()
-    }
-
-    fn extend_from_slice(&mut self, other: &[u8]) {
-        self.invariants();
-        let remaining = self.allocation.len() - self.written;
-        if other.len() > remaining {
-            panic!("calling extend_from_slice() with insufficient remaining capacity");
-        }
-        self.allocation[self.written..(self.written + other.len())].copy_from_slice(other);
-        self.written += other.len();
-        self.invariants();
-    }
-
-    fn pending(&self) -> usize {
-        self.written
-    }
-
-    fn flush(self) -> tokio_epoll_uring::Slice<Self> {
-        self.invariants();
-        let written = self.written;
-        tokio_epoll_uring::BoundedBuf::slice(self, 0..written)
-    }
-
-    fn reuse_after_flush(iobuf: Self::IoBuf) -> Self {
-        let Self {
-            mut allocation,
-            written,
-        } = iobuf;
-        allocation[0..written].fill(0);
-        let new = Self {
-            allocation,
-            written: 0,
-        };
-        new.invariants();
-        new
-    }
-}
-
-/// We have this trait impl so that the `flush` method in the `Buffer` impl above can produce a
-/// [`tokio_epoll_uring::BoundedBuf::slice`] of the [`Self::written`] range of the data.
-///
-/// Remember that bytes_init is generally _not_ a tracker of the amount
-/// of valid data in the io buffer; we use `Slice` for that.
-/// The `IoBuf` is _only_ for keeping track of uninitialized memory, a bit like MaybeUninit.
-///
-/// SAFETY:
-///
-/// The [`Self::allocation`] is stable becauses boxes are stable.
-/// The memory is zero-initialized, so, bytes_init is always N.
-unsafe impl<const N: usize> tokio_epoll_uring::IoBuf for Buffer<N> {
-    fn stable_ptr(&self) -> *const u8 {
-        self.allocation.as_ptr()
-    }
-
-    fn bytes_init(&self) -> usize {
-        // Yes, N, not self.written; Read the full comment of this impl block!
-        N
-    }
-
-    fn bytes_total(&self) -> usize {
-        N
-    }
-}
--- a/pageserver/src/tenant/metadata.rs
+++ b/pageserver/src/tenant/metadata.rs
@@ -235,12 +235,6 @@ impl TimelineMetadata {
        let bytes = instance.to_bytes().unwrap();
        Self::from_bytes(&bytes).unwrap()
    }
-
-    pub(crate) fn apply(&mut self, update: &MetadataUpdate) {
-        self.body.disk_consistent_lsn = update.disk_consistent_lsn;
-        self.body.prev_record_lsn = update.prev_record_lsn;
-        self.body.latest_gc_cutoff_lsn = update.latest_gc_cutoff_lsn;
-    }
 }

 impl<'de> Deserialize<'de> for TimelineMetadata {
@@ -265,27 +259,6 @@ impl Serialize for TimelineMetadata {
    }
 }

-/// Parts of the metadata which are regularly modified.
-pub(crate) struct MetadataUpdate {
-    disk_consistent_lsn: Lsn,
-    prev_record_lsn: Option<Lsn>,
-    latest_gc_cutoff_lsn: Lsn,
-}
-
-impl MetadataUpdate {
-    pub(crate) fn new(
-        disk_consistent_lsn: Lsn,
-        prev_record_lsn: Option<Lsn>,
-        latest_gc_cutoff_lsn: Lsn,
-    ) -> Self {
-        Self {
-            disk_consistent_lsn,
-            prev_record_lsn,
-            latest_gc_cutoff_lsn,
-        }
-    }
-}
-
 #[cfg(test)]
 mod tests {
    use super::*;
--- a/pageserver/src/tenant/remote_timeline_client.rs
+++ b/pageserver/src/tenant/remote_timeline_client.rs
@@ -202,9 +202,7 @@ use std::sync::atomic::{AtomicU32, Ordering};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;

-use remote_storage::{
-    DownloadError, GenericRemoteStorage, ListingMode, RemotePath, TimeoutOrCancel,
-};
+use remote_storage::{DownloadError, GenericRemoteStorage, RemotePath, TimeoutOrCancel};
 use std::ops::DerefMut;
 use tracing::{debug, error, info, instrument, warn};
 use tracing::{info_span, Instrument};
@@ -238,14 +236,11 @@ use utils::id::{TenantId, TimelineId};

 use self::index::IndexPart;

-use super::metadata::MetadataUpdate;
 use super::storage_layer::{Layer, LayerFileName, ResidentLayer};
 use super::upload_queue::SetDeletedFlagProgress;
 use super::Generation;

-pub(crate) use download::{
-    download_index_part, is_temp_download_file, list_remote_tenant_shards, list_remote_timelines,
-};
+pub(crate) use download::{is_temp_download_file, list_remote_timelines};
 pub(crate) use index::LayerFileMetadata;

 // Occasional network issues and such can cause remote operations to fail, and
@@ -474,7 +469,7 @@ impl RemoteTimelineClient {
            },
        );

-        let (index_part, _index_generation) = download::download_index_part(
+        let index_part = download::download_index_part(
            &self.storage_impl,
            &self.tenant_shard_id,
            &self.timeline_id,
@@ -541,10 +536,9 @@ impl RemoteTimelineClient {
    // Upload operations.
    //

-    /// Launch an index-file upload operation in the background, with
-    /// fully updated metadata.
    ///
-    /// This should only be used to upload initial metadata to remote storage.
+    /// Launch an index-file upload operation in the background, with
+    /// updated metadata.
    ///
    /// The upload will be added to the queue immediately, but it
    /// won't be performed until all previously scheduled layer file
@@ -556,7 +550,7 @@ impl RemoteTimelineClient {
    /// If there were any changes to the list of files, i.e. if any
    /// layer file uploads were scheduled, since the last index file
    /// upload, those will be included too.
-    pub fn schedule_index_upload_for_full_metadata_update(
+    pub fn schedule_index_upload_for_metadata_update(
        self: &Arc<Self>,
        metadata: &TimelineMetadata,
    ) -> anyhow::Result<()> {
@@ -572,27 +566,6 @@ impl RemoteTimelineClient {
        Ok(())
    }

-    /// Launch an index-file upload operation in the background, with only parts of the metadata
-    /// updated.
-    ///
-    /// This is the regular way of updating metadata on layer flushes or Gc.
-    ///
-    /// Using this lighter update mechanism allows for reparenting and detaching without changes to
-    /// `index_part.json`, while being more clear on what values update regularly.
-    pub(crate) fn schedule_index_upload_for_metadata_update(
-        self: &Arc<Self>,
-        update: &MetadataUpdate,
-    ) -> anyhow::Result<()> {
-        let mut guard = self.upload_queue.lock().unwrap();
-        let upload_queue = guard.initialized_mut()?;
-
-        upload_queue.latest_metadata.apply(update);
-
-        self.schedule_index_upload(upload_queue, upload_queue.latest_metadata.clone());
-
-        Ok(())
-    }
-
    ///
    /// Launch an index-file upload operation in the background, if necessary.
    ///
@@ -1149,7 +1122,7 @@ impl RemoteTimelineClient {
        // and retry will arrive to different pageserver there wont be any traces of it on remote storage
        let timeline_storage_path = remote_timeline_path(&self.tenant_shard_id, &self.timeline_id);

-        // Execute all pending deletions, so that when we proceed to do a listing below, we aren't
+        // Execute all pending deletions, so that when we proceed to do a list_prefixes below, we aren't
        // taking the burden of listing all the layers that we already know we should delete.
        self.flush_deletion_queue().await?;

@@ -1158,20 +1131,14 @@ impl RemoteTimelineClient {
        let remaining = download_retry(
            || async {
                self.storage_impl
-                    .list(
-                        Some(&timeline_storage_path),
-                        ListingMode::NoDelimiter,
-                        None,
-                        &cancel,
-                    )
+                    .list_files(Some(&timeline_storage_path), None, &cancel)
                    .await
            },
            "list remaining files",
            &cancel,
        )
        .await
-        .context("list files remaining files")?
-        .keys;
+        .context("list files remaining files")?;

        // We will delete the current index_part object last, since it acts as a deletion
        // marker via its deleted_at attribute
@@ -1718,11 +1685,6 @@ impl RemoteTimelineClient {
    }
 }

-pub fn remote_tenant_path(tenant_shard_id: &TenantShardId) -> RemotePath {
-    let path = format!("tenants/{tenant_shard_id}");
-    RemotePath::from_string(&path).expect("Failed to construct path")
-}
-
 pub fn remote_timelines_path(tenant_shard_id: &TenantShardId) -> RemotePath {
    let path = format!("tenants/{tenant_shard_id}/{TIMELINES_SEGMENT_NAME}");
    RemotePath::from_string(&path).expect("Failed to construct path")
@@ -2062,7 +2024,7 @@ mod tests {
        // Schedule upload of index. Check that it is queued
        let metadata = dummy_metadata(Lsn(0x20));
        client
-            .schedule_index_upload_for_full_metadata_update(&metadata)
+            .schedule_index_upload_for_metadata_update(&metadata)
            .unwrap();
        {
            let mut guard = client.upload_queue.lock().unwrap();
--- a/pageserver/src/tenant/remote_timeline_client/download.rs
+++ b/pageserver/src/tenant/remote_timeline_client/download.rs
@@ -5,7 +5,6 @@

 use std::collections::HashSet;
 use std::future::Future;
-use std::str::FromStr;

 use anyhow::{anyhow, Context};
 use camino::{Utf8Path, Utf8PathBuf};
@@ -26,13 +25,13 @@ use crate::virtual_file::{on_fatal_io_error, MaybeFatalIo, VirtualFile};
 use crate::TEMP_FILE_SUFFIX;
 use remote_storage::{DownloadError, GenericRemoteStorage, ListingMode, RemotePath};
 use utils::crashsafe::path_with_suffix_extension;
-use utils::id::{TenantId, TimelineId};
+use utils::id::TimelineId;

 use super::index::{IndexPart, LayerFileMetadata};
 use super::{
    parse_remote_index_path, remote_index_path, remote_initdb_archive_path,
-    remote_initdb_preserved_archive_path, remote_tenant_path, FAILED_DOWNLOAD_WARN_THRESHOLD,
-    FAILED_REMOTE_OP_RETRIES, INITDB_PATH,
+    remote_initdb_preserved_archive_path, FAILED_DOWNLOAD_WARN_THRESHOLD, FAILED_REMOTE_OP_RETRIES,
+    INITDB_PATH,
 };

 ///
@@ -183,7 +182,6 @@ async fn download_object<'a>(
        #[cfg(target_os = "linux")]
        crate::virtual_file::io_engine::IoEngine::TokioEpollUring => {
            use crate::virtual_file::owned_buffers_io::{self, util::size_tracking_writer};
-            use bytes::BytesMut;
            async {
                let destination_file = VirtualFile::create(dst_path)
                    .await
@@ -196,10 +194,10 @@ async fn download_object<'a>(
                // There's chunks_vectored() on the stream.
                let (bytes_amount, destination_file) = async {
                    let size_tracking = size_tracking_writer::Writer::new(destination_file);
-                    let mut buffered = owned_buffers_io::write::BufferedWriter::<BytesMut, _>::new(
-                        size_tracking,
-                        BytesMut::with_capacity(super::BUFFER_SIZE),
-                    );
+                    let mut buffered = owned_buffers_io::write::BufferedWriter::<
+                        { super::BUFFER_SIZE },
+                        _,
+                    >::new(size_tracking);
                    while let Some(res) =
                        futures::StreamExt::next(&mut download.download_stream).await
                    {
@@ -254,31 +252,42 @@ pub(crate) fn is_temp_download_file(path: &Utf8Path) -> bool {
    }
 }

-async fn list_identifiers<T>(
+/// List timelines of given tenant in remote storage
+pub async fn list_remote_timelines(
    storage: &GenericRemoteStorage,
-    prefix: RemotePath,
+    tenant_shard_id: TenantShardId,
    cancel: CancellationToken,
-) -> anyhow::Result<(HashSet<T>, HashSet<String>)>
-where
-    T: FromStr + Eq + std::hash::Hash,
-{
+) -> anyhow::Result<(HashSet<TimelineId>, HashSet<String>)> {
+    let remote_path = remote_timelines_path(&tenant_shard_id);
+
+    fail::fail_point!("storage-sync-list-remote-timelines", |_| {
+        anyhow::bail!("storage-sync-list-remote-timelines");
+    });
+
    let listing = download_retry_forever(
-        || storage.list(Some(&prefix), ListingMode::WithDelimiter, None, &cancel),
-        &format!("list identifiers in prefix {prefix}"),
+        || {
+            storage.list(
+                Some(&remote_path),
+                ListingMode::WithDelimiter,
+                None,
+                &cancel,
+            )
+        },
+        &format!("list timelines for {tenant_shard_id}"),
        &cancel,
    )
    .await?;

-    let mut parsed_ids = HashSet::new();
+    let mut timeline_ids = HashSet::new();
    let mut other_prefixes = HashSet::new();

-    for id_remote_storage_key in listing.prefixes {
-        let object_name = id_remote_storage_key.object_name().ok_or_else(|| {
-            anyhow::anyhow!("failed to get object name for key {id_remote_storage_key}")
+    for timeline_remote_storage_key in listing.prefixes {
+        let object_name = timeline_remote_storage_key.object_name().ok_or_else(|| {
+            anyhow::anyhow!("failed to get timeline id for remote tenant {tenant_shard_id}")
        })?;

-        match object_name.parse::<T>() {
-            Ok(t) => parsed_ids.insert(t),
+        match object_name.parse::<TimelineId>() {
+            Ok(t) => timeline_ids.insert(t),
            Err(_) => other_prefixes.insert(object_name.to_string()),
        };
    }
@@ -290,31 +299,7 @@ where
        other_prefixes.insert(object_name.to_string());
    }

-    Ok((parsed_ids, other_prefixes))
-}
-
-/// List shards of given tenant in remote storage
-pub(crate) async fn list_remote_tenant_shards(
-    storage: &GenericRemoteStorage,
-    tenant_id: TenantId,
-    cancel: CancellationToken,
-) -> anyhow::Result<(HashSet<TenantShardId>, HashSet<String>)> {
-    let remote_path = remote_tenant_path(&TenantShardId::unsharded(tenant_id));
-    list_identifiers::<TenantShardId>(storage, remote_path, cancel).await
-}
-
-/// List timelines of given tenant shard in remote storage
-pub async fn list_remote_timelines(
-    storage: &GenericRemoteStorage,
-    tenant_shard_id: TenantShardId,
-    cancel: CancellationToken,
-) -> anyhow::Result<(HashSet<TimelineId>, HashSet<String>)> {
-    fail::fail_point!("storage-sync-list-remote-timelines", |_| {
-        anyhow::bail!("storage-sync-list-remote-timelines");
-    });
-
-    let remote_path = remote_timelines_path(&tenant_shard_id).add_trailing_slash();
-    list_identifiers::<TimelineId>(storage, remote_path, cancel).await
+    Ok((timeline_ids, other_prefixes))
 }

 async fn do_download_index_part(
@@ -323,7 +308,7 @@ async fn do_download_index_part(
    timeline_id: &TimelineId,
    index_generation: Generation,
    cancel: &CancellationToken,
-) -> Result<(IndexPart, Generation), DownloadError> {
+) -> Result<IndexPart, DownloadError> {
    let remote_path = remote_index_path(tenant_shard_id, timeline_id, index_generation);

    let index_part_bytes = download_retry_forever(
@@ -348,7 +333,7 @@ async fn do_download_index_part(
        .with_context(|| format!("deserialize index part file at {remote_path:?}"))
        .map_err(DownloadError::Other)?;

-    Ok((index_part, index_generation))
+    Ok(index_part)
 }

 /// index_part.json objects are suffixed with a generation number, so we cannot
@@ -357,13 +342,13 @@ async fn do_download_index_part(
 /// In this function we probe for the most recent index in a generation <= our current generation.
 /// See "Finding the remote indices for timelines" in docs/rfcs/025-generation-numbers.md
 #[tracing::instrument(skip_all, fields(generation=?my_generation))]
-pub(crate) async fn download_index_part(
+pub(super) async fn download_index_part(
    storage: &GenericRemoteStorage,
    tenant_shard_id: &TenantShardId,
    timeline_id: &TimelineId,
    my_generation: Generation,
    cancel: &CancellationToken,
-) -> Result<(IndexPart, Generation), DownloadError> {
+) -> Result<IndexPart, DownloadError> {
    debug_assert_current_span_has_tenant_and_timeline_id();

    if my_generation.is_none() {
@@ -432,16 +417,11 @@ pub(crate) async fn download_index_part(
    let index_prefix = remote_index_path(tenant_shard_id, timeline_id, Generation::none());

    let indices = download_retry(
-        || async {
-            storage
-                .list(Some(&index_prefix), ListingMode::NoDelimiter, None, cancel)
-                .await
-        },
+        || async { storage.list_files(Some(&index_prefix), None, cancel).await },
        "list index_part files",
        cancel,
    )
-    .await?
-    .keys;
+    .await?;

    // General case logic for which index to use: the latest index whose generation
    // is <= our own.  See "Finding the remote indices for timelines" in docs/rfcs/025-generation-numbers.md
--- a/pageserver/src/tenant/size.rs
+++ b/pageserver/src/tenant/size.rs
@@ -118,9 +118,6 @@ pub(super) async fn gather_inputs(
    ctx: &RequestContext,
 ) -> anyhow::Result<ModelInputs> {
    // refresh is needed to update gc related pitr_cutoff and horizon_cutoff
-    //
-    // FIXME: if a single timeline is deleted while refresh gc info is ongoing, we will fail the
-    // whole computation. It does not make sense from the billing perspective.
    tenant
        .refresh_gc_info(cancel, ctx)
        .await
--- a/pageserver/src/tenant/storage_layer.rs
+++ b/pageserver/src/tenant/storage_layer.rs
@@ -118,7 +118,6 @@ pub(crate) struct ValuesReconstructState {
    pub(crate) keys: HashMap<Key, Result<VectoredValueReconstructState, PageReconstructError>>,

    keys_done: KeySpaceRandomAccum,
-    layers_visited: u32,
 }

 impl ValuesReconstructState {
@@ -126,7 +125,6 @@ impl ValuesReconstructState {
        Self {
            keys: HashMap::new(),
            keys_done: KeySpaceRandomAccum::new(),
-            layers_visited: 0,
        }
    }

@@ -140,37 +138,6 @@ impl ValuesReconstructState {
        }
    }

-    pub(crate) fn on_layer_visited(&mut self) {
-        self.layers_visited += 1;
-    }
-
-    pub(crate) fn get_layers_visited(&self) -> u32 {
-        self.layers_visited
-    }
-
-    /// This function is called after reading a keyspace from a layer.
-    /// It checks if the read path has now moved past the cached Lsn for any keys.
-    ///
-    /// Implementation note: We intentionally iterate over the keys for which we've
-    /// already collected some reconstruct data. This avoids scaling complexity with
-    /// the size of the search space.
-    pub(crate) fn on_lsn_advanced(&mut self, keyspace: &KeySpace, advanced_to: Lsn) {
-        for (key, value) in self.keys.iter_mut() {
-            if !keyspace.contains(key) {
-                continue;
-            }
-
-            if let Ok(state) = value {
-                if state.situation != ValueReconstructSituation::Complete
-                    && state.get_cached_lsn() >= Some(advanced_to)
-                {
-                    state.situation = ValueReconstructSituation::Complete;
-                    self.keys_done.add_key(*key);
-                }
-            }
-        }
-    }
-
    /// Update the state collected for a given key.
    /// Returns true if this was the last value needed for the key and false otherwise.
    ///
@@ -195,18 +162,11 @@ impl ValuesReconstructState {
                        true
                    }
                    Value::WalRecord(rec) => {
-                        debug_assert!(
-                            Some(lsn) > state.get_cached_lsn(),
-                            "Attempt to collect a record below cached LSN for walredo: {} < {}",
-                            lsn,
-                            state
-                                .get_cached_lsn()
-                                .expect("Assertion can only fire if a cached lsn is present")
-                        );
-
+                        let reached_cache =
+                            state.get_cached_lsn().map(|clsn| clsn + 1) == Some(lsn);
                        let will_init = rec.will_init();
                        state.records.push((lsn, rec));
-                        will_init
+                        will_init || reached_cache
                    }
                },
            };
--- a/pageserver/src/tenant/storage_layer/delta_layer.rs
+++ b/pageserver/src/tenant/storage_layer/delta_layer.rs
@@ -217,7 +217,6 @@ pub struct DeltaLayerInner {
    // values copied from summary
    index_start_blk: u32,
    index_root_blk: u32,
-    lsn_range: Range<Lsn>,

    file: VirtualFile,
    file_id: FileId,
@@ -729,9 +728,6 @@ impl DeltaLayerInner {
            // production code path
            expected_summary.index_start_blk = actual_summary.index_start_blk;
            expected_summary.index_root_blk = actual_summary.index_root_blk;
-            // mask out the timeline_id, but still require the layers to be from the same tenant
-            expected_summary.timeline_id = actual_summary.timeline_id;
-
            if actual_summary != expected_summary {
                bail!(
                    "in-file summary does not match expected summary. actual = {:?} expected = {:?}",
@@ -746,7 +742,6 @@ impl DeltaLayerInner {
            file_id,
            index_start_blk: actual_summary.index_start_blk,
            index_root_blk: actual_summary.index_root_blk,
-            lsn_range: actual_summary.lsn_range,
            max_vectored_read_bytes,
        }))
    }
@@ -871,7 +866,7 @@ impl DeltaLayerInner {
        let data_end_offset = self.index_start_offset();

        let reads = Self::plan_reads(
-            &keyspace,
+            keyspace,
            lsn_range,
            data_end_offset,
            index_reader,
@@ -885,13 +880,11 @@ impl DeltaLayerInner {
        self.do_reads_and_update_state(reads, reconstruct_state)
            .await;

-        reconstruct_state.on_lsn_advanced(&keyspace, self.lsn_range.start);
-
        Ok(())
    }

    async fn plan_reads<Reader>(
-        keyspace: &KeySpace,
+        keyspace: KeySpace,
        lsn_range: Range<Lsn>,
        data_end_offset: u64,
        index_reader: DiskBtreeReader<Reader, DELTA_KEY_SIZE>,
@@ -1539,7 +1532,7 @@ mod test {

        // Plan and validate
        let vectored_reads = DeltaLayerInner::plan_reads(
-            &keyspace,
+            keyspace.clone(),
            lsn_range.clone(),
            disk_offset,
            reader,
@@ -1791,7 +1784,7 @@ mod test {
            let data_end_offset = inner.index_start_blk as u64 * PAGE_SZ as u64;

            let vectored_reads = DeltaLayerInner::plan_reads(
-                &keyspace,
+                keyspace.clone(),
                entries_meta.lsn_range.clone(),
                data_end_offset,
                index_reader,
--- a/pageserver/src/tenant/storage_layer/image_layer.rs
+++ b/pageserver/src/tenant/storage_layer/image_layer.rs
@@ -396,8 +396,6 @@ impl ImageLayerInner {
            // production code path
            expected_summary.index_start_blk = actual_summary.index_start_blk;
            expected_summary.index_root_blk = actual_summary.index_root_blk;
-            // mask out the timeline_id, but still require the layers to be from the same tenant
-            expected_summary.timeline_id = actual_summary.timeline_id;

            if actual_summary != expected_summary {
                bail!(
--- a/pageserver/src/tenant/storage_layer/inmemory_layer.rs
+++ b/pageserver/src/tenant/storage_layer/inmemory_layer.rs
@@ -17,7 +17,7 @@ use anyhow::{anyhow, ensure, Result};
 use pageserver_api::keyspace::KeySpace;
 use pageserver_api::models::InMemoryLayerInfo;
 use pageserver_api::shard::TenantShardId;
-use std::collections::{BTreeMap, BinaryHeap, HashSet};
+use std::collections::{BinaryHeap, HashMap, HashSet};
 use std::sync::{Arc, OnceLock};
 use std::time::Instant;
 use tracing::*;
@@ -26,7 +26,7 @@ use utils::{bin_ser::BeSer, id::TimelineId, lsn::Lsn, vec_map::VecMap};
 // while being able to use std::fmt::Write's methods
 use crate::metrics::TIMELINE_EPHEMERAL_BYTES;
 use std::cmp::Ordering;
-use std::fmt::Write;
+use std::fmt::Write as _;
 use std::ops::Range;
 use std::sync::atomic::Ordering as AtomicOrdering;
 use std::sync::atomic::{AtomicU64, AtomicUsize};
@@ -54,12 +54,6 @@ pub struct InMemoryLayer {
    /// Writes are only allowed when this is `None`.
    end_lsn: OnceLock<Lsn>,

-    /// Used for traversal path. Cached representation of the in-memory layer before frozen.
-    local_path_str: Arc<str>,
-
-    /// Used for traversal path. Cached representation of the in-memory layer after frozen.
-    frozen_local_path_str: OnceLock<Arc<str>>,
-
    opened_at: Instant,

    /// The above fields never change, except for `end_lsn`, which is only set once.
@@ -78,10 +72,10 @@ impl std::fmt::Debug for InMemoryLayer {
 }

 pub struct InMemoryLayerInner {
-    /// All versions of all pages in the layer are kept here. Indexed
+    /// All versions of all pages in the layer are kept here.  Indexed
    /// by block number and LSN. The value is an offset into the
    /// ephemeral file where the page version is stored.
-    index: BTreeMap<Key, VecMap<Lsn, u64>>,
+    index: HashMap<Key, VecMap<Lsn, u64>>,

    /// The values are stored in a serialized format in this file.
    /// Each serialized Value is preceded by a 'u32' length field.
@@ -247,12 +241,6 @@ impl InMemoryLayer {
        self.start_lsn..self.end_lsn_or_max()
    }

-    pub(crate) fn local_path_str(&self) -> &Arc<str> {
-        self.frozen_local_path_str
-            .get()
-            .unwrap_or(&self.local_path_str)
-    }
-
    /// debugging function to print out the contents of the layer
    ///
    /// this is likely completly unused
@@ -384,24 +372,29 @@ impl InMemoryLayer {
        let mut planned_block_reads = BinaryHeap::new();

        for range in keyspace.ranges.iter() {
-            for (key, vec_map) in inner.index.range(range.start..range.end) {
-                let lsn_range = match reconstruct_state.get_cached_lsn(key) {
-                    Some(cached_lsn) => (cached_lsn + 1)..end_lsn,
-                    None => self.start_lsn..end_lsn,
-                };
+            let mut key = range.start;
+            while key < range.end {
+                if let Some(vec_map) = inner.index.get(&key) {
+                    let lsn_range = match reconstruct_state.get_cached_lsn(&key) {
+                        Some(cached_lsn) => (cached_lsn + 1)..end_lsn,
+                        None => self.start_lsn..end_lsn,
+                    };

-                let slice = vec_map.slice_range(lsn_range);
-                for (entry_lsn, pos) in slice.iter().rev() {
-                    planned_block_reads.push(BlockRead {
-                        key: *key,
-                        lsn: *entry_lsn,
-                        block_offset: *pos,
-                    });
+                    let slice = vec_map.slice_range(lsn_range);
+                    for (entry_lsn, pos) in slice.iter().rev() {
+                        planned_block_reads.push(BlockRead {
+                            key,
+                            lsn: *entry_lsn,
+                            block_offset: *pos,
+                        });
+                    }
                }
+
+                key = key.next();
            }
        }

-        let keyspace_size = keyspace.total_raw_size();
+        let keyspace_size = keyspace.total_size();

        let mut completed_keys = HashSet::new();
        while completed_keys.len() < keyspace_size && !planned_block_reads.is_empty() {
@@ -433,30 +426,14 @@ impl InMemoryLayer {
            }
        }

-        reconstruct_state.on_lsn_advanced(&keyspace, self.start_lsn);
-
        Ok(())
    }
 }

-fn inmem_layer_display(mut f: impl Write, start_lsn: Lsn, end_lsn: Lsn) -> std::fmt::Result {
-    write!(f, "inmem-{:016X}-{:016X}", start_lsn.0, end_lsn.0)
-}
-
-fn inmem_layer_log_display(
-    mut f: impl Write,
-    timeline: TimelineId,
-    start_lsn: Lsn,
-    end_lsn: Lsn,
-) -> std::fmt::Result {
-    write!(f, "timeline {} in-memory ", timeline)?;
-    inmem_layer_display(f, start_lsn, end_lsn)
-}
-
 impl std::fmt::Display for InMemoryLayer {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let end_lsn = self.end_lsn_or_max();
-        inmem_layer_display(f, self.start_lsn, end_lsn)
+        write!(f, "inmem-{:016X}-{:016X}", self.start_lsn.0, end_lsn.0)
    }
 }

@@ -477,16 +454,10 @@ impl InMemoryLayer {
        trace!("initializing new empty InMemoryLayer for writing on timeline {timeline_id} at {start_lsn}");

        let file = EphemeralFile::create(conf, tenant_shard_id, timeline_id).await?;
-        let key = InMemoryLayerFileId(file.page_cache_file_id());
+        let key = InMemoryLayerFileId(file.id());

        Ok(InMemoryLayer {
            file_id: key,
-            local_path_str: {
-                let mut buf = String::new();
-                inmem_layer_log_display(&mut buf, timeline_id, start_lsn, Lsn::MAX).unwrap();
-                buf.into()
-            },
-            frozen_local_path_str: OnceLock::new(),
            conf,
            timeline_id,
            tenant_shard_id,
@@ -494,7 +465,7 @@ impl InMemoryLayer {
            end_lsn: OnceLock::new(),
            opened_at: Instant::now(),
            inner: RwLock::new(InMemoryLayerInner {
-                index: BTreeMap::new(),
+                index: HashMap::new(),
                file,
                resource_units: GlobalResourceUnits::new(),
            }),
@@ -581,15 +552,6 @@ impl InMemoryLayer {
        );
        self.end_lsn.set(end_lsn).expect("end_lsn set only once");

-        self.frozen_local_path_str
-            .set({
-                let mut buf = String::new();
-                inmem_layer_log_display(&mut buf, self.get_timeline_id(), self.start_lsn, end_lsn)
-                    .unwrap();
-                buf.into()
-            })
-            .expect("frozen_local_path_str set only once");
-
        for vec_map in inner.index.values() {
            for (lsn, _pos) in vec_map.as_slice() {
                assert!(*lsn < end_lsn);
@@ -631,17 +593,26 @@ impl InMemoryLayer {

        let cursor = inner.file.block_cursor();

+        // Sort the keys because delta layer writer expects them sorted.
+        //
+        // NOTE: this sort can take up significant time if the layer has millions of
+        //       keys. To speed up all the comparisons we convert the key to i128 and
+        //       keep the value as a reference.
+        let mut keys: Vec<_> = inner.index.iter().map(|(k, m)| (k.to_i128(), m)).collect();
+        keys.sort_unstable_by_key(|k| k.0);
+
        let ctx = RequestContextBuilder::extend(ctx)
            .page_content_kind(PageContentKind::InMemoryLayer)
            .build();
-        for (key, vec_map) in inner.index.iter() {
+        for (key, vec_map) in keys.iter() {
+            let key = Key::from_i128(*key);
            // Write all page versions
            for (lsn, pos) in vec_map.as_slice() {
                cursor.read_blob_into_buf(*pos, &mut buf, &ctx).await?;
                let will_init = Value::des(&buf)?.will_init();
                let res;
                (buf, res) = delta_layer_writer
-                    .put_value_bytes(*key, *lsn, buf, will_init)
+                    .put_value_bytes(key, *lsn, buf, will_init)
                    .await;
                res?;
            }
--- a/pageserver/src/tenant/storage_layer/layer.rs
+++ b/pageserver/src/tenant/storage_layer/layer.rs
@@ -336,12 +336,6 @@ impl Layer {
            .get_values_reconstruct_data(keyspace, lsn_range, reconstruct_data, &self.0, ctx)
            .instrument(tracing::debug_span!("get_values_reconstruct_data", layer=%self))
            .await
-            .map_err(|err| match err {
-                GetVectoredError::Other(err) => GetVectoredError::Other(
-                    err.context(format!("get_values_reconstruct_data for layer {self}")),
-                ),
-                err => err,
-            })
    }

    /// Download the layer if evicted.
@@ -401,10 +395,6 @@ impl Layer {
        &self.0.path
    }

-    pub(crate) fn local_path_str(&self) -> &Arc<str> {
-        &self.0.path_str
-    }
-
    pub(crate) fn metadata(&self) -> LayerFileMetadata {
        self.0.metadata()
    }
@@ -527,9 +517,6 @@ struct LayerInner {
    /// Full path to the file; unclear if this should exist anymore.
    path: Utf8PathBuf,

-    /// String representation of the full path, used for traversal id.
-    path_str: Arc<str>,
-
    desc: PersistentLayerDesc,

    /// Timeline access is needed for remote timeline client and metrics.
@@ -735,7 +722,6 @@ impl LayerInner {

        LayerInner {
            conf,
-            path_str: path.to_string().into(),
            path,
            desc,
            timeline: Arc::downgrade(timeline),
--- a/pageserver/src/tenant/storage_layer/layer/tests.rs
+++ b/pageserver/src/tenant/storage_layer/layer/tests.rs
@@ -818,13 +818,11 @@ async fn eviction_cancellation_on_drop() {
    }
 }

-/// A test case to remind you the cost of these structures. You can bump the size limit
-/// below if it is really necessary to add more fields to the structures.
 #[test]
 fn layer_size() {
    assert_eq!(std::mem::size_of::<LayerAccessStats>(), 2040);
    assert_eq!(std::mem::size_of::<PersistentLayerDesc>(), 104);
-    assert_eq!(std::mem::size_of::<LayerInner>(), 2344);
+    assert_eq!(std::mem::size_of::<LayerInner>(), 2328);
    // it also has the utf8 path
 }

--- a/pageserver/src/tenant/tasks.rs
+++ b/pageserver/src/tenant/tasks.rs
@@ -62,7 +62,7 @@ impl BackgroundLoopKind {
 pub(crate) async fn concurrent_background_tasks_rate_limit_permit(
    loop_kind: BackgroundLoopKind,
    _ctx: &RequestContext,
-) -> tokio::sync::SemaphorePermit<'static> {
+) -> impl Drop {
    let _guard = crate::metrics::BACKGROUND_LOOP_SEMAPHORE_WAIT_GAUGE
        .with_label_values(&[loop_kind.as_static_str()])
        .guard();
--- a/pageserver/src/tenant/timeline.rs
+++ b/pageserver/src/tenant/timeline.rs
@@ -16,14 +16,14 @@ use enumset::EnumSet;
 use fail::fail_point;
 use once_cell::sync::Lazy;
 use pageserver_api::{
-    key::{AUX_FILES_KEY, NON_INHERITED_RANGE},
+    key::AUX_FILES_KEY,
    keyspace::KeySpaceAccum,
    models::{
        CompactionAlgorithm, DownloadRemoteLayersTaskInfo, DownloadRemoteLayersTaskSpawnRequest,
        EvictionPolicy, InMemoryLayerInfo, LayerMapInfo, TimelineState,
    },
    reltag::BlockNumber,
-    shard::{ShardIdentity, ShardNumber, TenantShardId},
+    shard::{ShardIdentity, TenantShardId},
 };
 use rand::Rng;
 use serde_with::serde_as;
@@ -86,7 +86,7 @@ use crate::{
 use crate::config::PageServerConf;
 use crate::keyspace::{KeyPartitioning, KeySpace};
 use crate::metrics::{
-    GetKind, TimelineMetrics, MATERIALIZED_PAGE_CACHE_HIT, MATERIALIZED_PAGE_CACHE_HIT_DIRECT,
+    TimelineMetrics, MATERIALIZED_PAGE_CACHE_HIT, MATERIALIZED_PAGE_CACHE_HIT_DIRECT,
 };
 use crate::pgdatadir_mapping::CalculateLogicalSizeError;
 use crate::tenant::config::TenantConfOpt;
@@ -119,8 +119,8 @@ use self::layer_manager::LayerManager;
 use self::logical_size::LogicalSize;
 use self::walreceiver::{WalReceiver, WalReceiverConf};

+use super::config::TenantConf;
 use super::secondary::heatmap::{HeatMapLayer, HeatMapTimeline};
-use super::{config::TenantConf, storage_layer::VectoredValueReconstructState};
 use super::{debug_assert_current_span_has_tenant_and_timeline_id, AttachedTenantConf};
 use super::{remote_timeline_client::index::IndexPart, storage_layer::LayerFringe};
 use super::{remote_timeline_client::RemoteTimelineClient, storage_layer::ReadableLayer};
@@ -182,16 +182,6 @@ pub(crate) struct AuxFilesState {
    pub(crate) n_deltas: usize,
 }

-/// The relation size cache caches relation sizes at the end of the timeline. It speeds up WAL
-/// ingestion considerably, because WAL ingestion needs to check on most records if the record
-/// implicitly extends the relation.  At startup, `complete_as_of` is initialized to the current end
-/// of the timeline (disk_consistent_lsn).  It's used on reads of relation sizes to check if the
-/// value can be used to also update the cache, see [`Timeline::update_cached_rel_size`].
-pub(crate) struct RelSizeCache {
-    pub(crate) complete_as_of: Lsn,
-    pub(crate) map: HashMap<RelTag, (Lsn, BlockNumber)>,
-}
-
 pub struct Timeline {
    conf: &'static PageServerConf,
    tenant_conf: Arc<ArcSwap<AttachedTenantConf>>,
@@ -334,7 +324,7 @@ pub struct Timeline {
    pub walreceiver: Mutex<Option<WalReceiver>>,

    /// Relation size cache
-    pub(crate) rel_size_cache: RwLock<RelSizeCache>,
+    pub rel_size_cache: RwLock<HashMap<RelTag, (Lsn, BlockNumber)>>,

    download_all_remote_layers_task_info: RwLock<Option<DownloadRemoteLayersTaskInfo>>,

@@ -438,62 +428,6 @@ pub(crate) enum PageReconstructError {
    /// An error happened replaying WAL records
    #[error(transparent)]
    WalRedo(anyhow::Error),
-
-    #[error("{0}")]
-    MissingKey(MissingKeyError),
-}
-
-#[derive(Debug)]
-pub struct MissingKeyError {
-    stuck_at_lsn: bool,
-    key: Key,
-    shard: ShardNumber,
-    cont_lsn: Lsn,
-    request_lsn: Lsn,
-    ancestor_lsn: Option<Lsn>,
-    traversal_path: Vec<TraversalPathItem>,
-    backtrace: Option<std::backtrace::Backtrace>,
-}
-
-impl std::fmt::Display for MissingKeyError {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        if self.stuck_at_lsn {
-            // Records are found in this timeline but no image layer or initial delta record was found.
-            write!(
-                f,
-                "could not find layer with more data for key {} (shard {:?}) at LSN {}, request LSN {}",
-                self.key, self.shard, self.cont_lsn, self.request_lsn
-            )?;
-            if let Some(ref ancestor_lsn) = self.ancestor_lsn {
-                write!(f, ", ancestor {}", ancestor_lsn)?;
-            }
-        } else {
-            // No records in this timeline.
-            write!(
-                f,
-                "could not find data for key {} (shard {:?}) at LSN {}, for request at LSN {}",
-                self.key, self.shard, self.cont_lsn, self.request_lsn
-            )?;
-        }
-
-        if !self.traversal_path.is_empty() {
-            writeln!(f)?;
-        }
-
-        for (r, c, l) in &self.traversal_path {
-            writeln!(
-                f,
-                "layer traversal: result {:?}, cont_lsn {}, layer: {}",
-                r, c, l,
-            )?;
-        }
-
-        if let Some(ref backtrace) = self.backtrace {
-            write!(f, "\n{}", backtrace)?;
-        }
-
-        Ok(())
-    }
 }

 impl PageReconstructError {
@@ -505,7 +439,6 @@ impl PageReconstructError {
            AncestorLsnTimeout(_) => false,
            Cancelled | AncestorStopping(_) => true,
            WalRedo(_) => false,
-            MissingKey { .. } => false,
        }
    }
 }
@@ -653,19 +586,6 @@ impl From<GetVectoredError> for CreateImageLayersError {
    }
 }

-impl From<GetVectoredError> for PageReconstructError {
-    fn from(e: GetVectoredError) -> Self {
-        match e {
-            GetVectoredError::Cancelled => PageReconstructError::Cancelled,
-            GetVectoredError::InvalidLsn(_) => PageReconstructError::Other(anyhow!("Invalid LSN")),
-            err @ GetVectoredError::Oversized(_) => PageReconstructError::Other(err.into()),
-            err @ GetVectoredError::MissingKey(_) => PageReconstructError::Other(err.into()),
-            GetVectoredError::GetReadyAncestorError(err) => PageReconstructError::from(err),
-            GetVectoredError::Other(err) => PageReconstructError::Other(err),
-        }
-    }
-}
-
 impl From<GetReadyAncestorError> for PageReconstructError {
    fn from(e: GetReadyAncestorError) -> Self {
        use GetReadyAncestorError::*;
@@ -695,23 +615,6 @@ pub enum GetVectoredImpl {
    Vectored,
 }

-#[derive(
-    Eq,
-    PartialEq,
-    Debug,
-    Copy,
-    Clone,
-    strum_macros::EnumString,
-    strum_macros::Display,
-    serde_with::DeserializeFromStr,
-    serde_with::SerializeDisplay,
-)]
-#[strum(serialize_all = "kebab-case")]
-pub enum GetImpl {
-    Legacy,
-    Vectored,
-}
-
 pub(crate) enum WaitLsnWaiter<'a> {
    Timeline(&'a Timeline),
    Tenant,
@@ -773,6 +676,16 @@ impl Timeline {
        key: Key,
        lsn: Lsn,
        ctx: &RequestContext,
+    ) -> Result<Bytes, PageReconstructError> {
+        self.timeline_get_throttle.throttle(ctx, 1).await;
+        self.get_impl(key, lsn, ctx).await
+    }
+    /// Not subject to [`Self::timeline_get_throttle`].
+    async fn get_impl(
+        &self,
+        key: Key,
+        lsn: Lsn,
+        ctx: &RequestContext,
    ) -> Result<Bytes, PageReconstructError> {
        if !lsn.is_valid() {
            return Err(PageReconstructError::Other(anyhow::anyhow!("Invalid LSN")));
@@ -783,7 +696,13 @@ impl Timeline {
        // page_service.
        debug_assert!(!self.shard_identity.is_key_disposable(&key));

-        self.timeline_get_throttle.throttle(ctx, 1).await;
+        // XXX: structured stats collection for layer eviction here.
+        trace!(
+            "get page request for {}@{} from task kind {:?}",
+            key,
+            lsn,
+            ctx.task_kind()
+        );

        // Check the page cache. We will get back the most recent page with lsn <= `lsn`.
        // The cached image can be returned directly if there is no WAL between the cached image
@@ -806,85 +725,12 @@ impl Timeline {
            None => None,
        };

-        match self.conf.get_impl {
-            GetImpl::Legacy => {
-                let reconstruct_state = ValueReconstructState {
-                    records: Vec::new(),
-                    img: cached_page_img,
-                };
+        let mut reconstruct_state = ValueReconstructState {
+            records: Vec::new(),
+            img: cached_page_img,
+        };

-                self.get_impl(key, lsn, reconstruct_state, ctx).await
-            }
-            GetImpl::Vectored => {
-                let keyspace = KeySpace {
-                    ranges: vec![key..key.next()],
-                };
-
-                // Initialise the reconstruct state for the key with the cache
-                // entry returned above.
-                let mut reconstruct_state = ValuesReconstructState::new();
-                let mut key_state = VectoredValueReconstructState::default();
-                key_state.img = cached_page_img;
-                reconstruct_state.keys.insert(key, Ok(key_state));
-
-                let vectored_res = self
-                    .get_vectored_impl(keyspace.clone(), lsn, reconstruct_state, ctx)
-                    .await;
-
-                if self.conf.validate_vectored_get {
-                    self.validate_get_vectored_impl(&vectored_res, keyspace, lsn, ctx)
-                        .await;
-                }
-
-                let key_value = vectored_res?.pop_first();
-                match key_value {
-                    Some((got_key, value)) => {
-                        if got_key != key {
-                            error!(
-                                "Expected {}, but singular vectored get returned {}",
-                                key, got_key
-                            );
-                            Err(PageReconstructError::Other(anyhow!(
-                                "Singular vectored get returned wrong key"
-                            )))
-                        } else {
-                            value
-                        }
-                    }
-                    None => {
-                        error!(
-                            "Expected {}, but singular vectored get returned nothing",
-                            key
-                        );
-                        Err(PageReconstructError::Other(anyhow!(
-                            "Singular vectored get did not return a value for {}",
-                            key
-                        )))
-                    }
-                }
-            }
-        }
-    }
-
-    /// Not subject to [`Self::timeline_get_throttle`].
-    async fn get_impl(
-        &self,
-        key: Key,
-        lsn: Lsn,
-        mut reconstruct_state: ValueReconstructState,
-        ctx: &RequestContext,
-    ) -> Result<Bytes, PageReconstructError> {
-        // XXX: structured stats collection for layer eviction here.
-        trace!(
-            "get page request for {}@{} from task kind {:?}",
-            key,
-            lsn,
-            ctx.task_kind()
-        );
-
-        let timer = crate::metrics::GET_RECONSTRUCT_DATA_TIME
-            .for_get_kind(GetKind::Singular)
-            .start_timer();
+        let timer = crate::metrics::GET_RECONSTRUCT_DATA_TIME.start_timer();
        let path = self
            .get_reconstruct_data(key, lsn, &mut reconstruct_state, ctx)
            .await?;
@@ -894,7 +740,7 @@ impl Timeline {
        let res = self.reconstruct_value(key, lsn, reconstruct_state).await;
        let elapsed = start.elapsed();
        crate::metrics::RECONSTRUCT_TIME
-            .for_get_kind(GetKind::Singular)
+            .for_result(&res)
            .observe(elapsed.as_secs_f64());

        if cfg!(feature = "testing") && res.is_err() {
@@ -907,7 +753,7 @@ impl Timeline {
                writeln!(
                    msg,
                    "- layer traversal: result {res:?}, cont_lsn {cont_lsn}, layer: {}",
-                    layer,
+                    layer(),
                )
                .expect("string grows")
            });
@@ -936,7 +782,7 @@ impl Timeline {
            return Err(GetVectoredError::InvalidLsn(lsn));
        }

-        let key_count = keyspace.total_raw_size().try_into().unwrap();
+        let key_count = keyspace.total_size().try_into().unwrap();
        if key_count > Timeline::MAX_GET_VECTORED_KEYS {
            return Err(GetVectoredError::Oversized(key_count));
        }
@@ -973,9 +819,7 @@ impl Timeline {
                self.get_vectored_sequential_impl(keyspace, lsn, ctx).await
            }
            GetVectoredImpl::Vectored => {
-                let vectored_res = self
-                    .get_vectored_impl(keyspace.clone(), lsn, ValuesReconstructState::new(), ctx)
-                    .await;
+                let vectored_res = self.get_vectored_impl(keyspace.clone(), lsn, ctx).await;

                if self.conf.validate_vectored_get {
                    self.validate_get_vectored_impl(&vectored_res, keyspace, lsn, ctx)
@@ -1021,42 +865,15 @@ impl Timeline {
        for range in keyspace.ranges {
            let mut key = range.start;
            while key != range.end {
-                let block = self
-                    .get_impl(key, lsn, ValueReconstructState::default(), ctx)
-                    .await;
+                let block = self.get_impl(key, lsn, ctx).await;

                use PageReconstructError::*;
                match block {
                    Err(Cancelled | AncestorStopping(_)) => {
                        return Err(GetVectoredError::Cancelled)
                    }
-                    // we only capture stuck_at_lsn=false now until we figure out https://github.com/neondatabase/neon/issues/7380
-                    Err(MissingKey(MissingKeyError {
-                        stuck_at_lsn: false,
-                        ..
-                    })) if !NON_INHERITED_RANGE.contains(&key) => {
-                        // The vectored read path handles non inherited keys specially.
-                        // If such a a key cannot be reconstructed from the current timeline,
-                        // the vectored read path returns a key level error as opposed to a top
-                        // level error.
-                        return Err(GetVectoredError::MissingKey(key));
-                    }
-                    Err(Other(err))
-                        if err
-                            .to_string()
-                            .contains("downloading evicted layer file failed") =>
-                    {
-                        return Err(GetVectoredError::Other(err))
-                    }
-                    Err(Other(err))
-                        if err
-                            .chain()
-                            .any(|cause| cause.to_string().contains("layer loading failed")) =>
-                    {
-                        // The intent here is to achieve error parity with the vectored read path.
-                        // When vectored read fails to load a layer it fails the whole read, hence
-                        // we mimic this behaviour here to keep the validation happy.
-                        return Err(GetVectoredError::Other(err));
+                    Err(Other(err)) if err.to_string().contains("could not find data for key") => {
+                        return Err(GetVectoredError::MissingKey(key))
                    }
                    _ => {
                        values.insert(key, block);
@@ -1073,27 +890,14 @@ impl Timeline {
        &self,
        keyspace: KeySpace,
        lsn: Lsn,
-        mut reconstruct_state: ValuesReconstructState,
        ctx: &RequestContext,
    ) -> Result<BTreeMap<Key, Result<Bytes, PageReconstructError>>, GetVectoredError> {
-        let get_kind = if keyspace.total_raw_size() == 1 {
-            GetKind::Singular
-        } else {
-            GetKind::Vectored
-        };
+        let mut reconstruct_state = ValuesReconstructState::new();

-        let get_data_timer = crate::metrics::GET_RECONSTRUCT_DATA_TIME
-            .for_get_kind(get_kind)
-            .start_timer();
        self.get_vectored_reconstruct_data(keyspace, lsn, &mut reconstruct_state, ctx)
            .await?;
-        get_data_timer.stop_and_record();

-        let reconstruct_timer = crate::metrics::RECONSTRUCT_TIME
-            .for_get_kind(get_kind)
-            .start_timer();
        let mut results: BTreeMap<Key, Result<Bytes, PageReconstructError>> = BTreeMap::new();
-        let layers_visited = reconstruct_state.get_layers_visited();
        for (key, res) in reconstruct_state.keys {
            match res {
                Err(err) => {
@@ -1107,13 +911,6 @@ impl Timeline {
                }
            }
        }
-        reconstruct_timer.stop_and_record();
-
-        // Note that this is an approximation. Tracking the exact number of layers visited
-        // per key requires virtually unbounded memory usage and is inefficient
-        // (i.e. segment tree tracking each range queried from a layer)
-        crate::metrics::VEC_READ_NUM_LAYERS_VISITED
-            .observe(layers_visited as f64 / results.len() as f64);

        Ok(results)
    }
@@ -1149,11 +946,6 @@ impl Timeline {
                panic!(concat!("Sequential get failed with {}, but vectored get did not",
                               " - keyspace={:?} lsn={}"),
                       seq_err, keyspace, lsn) },
-            (Ok(_), Err(GetVectoredError::GetReadyAncestorError(GetReadyAncestorError::AncestorLsnTimeout(_)))) => {
-                // Sequential get runs after vectored get, so it is possible for the later 
-                // to time out while waiting for its ancestor's Lsn to become ready and for the
-                // former to succeed (it essentially has a doubled wait time).
-            },
            (Ok(_), Err(vec_err)) => {
                panic!(concat!("Vectored get failed with {}, but sequential get did not",
                               " - keyspace={:?} lsn={}"),
@@ -1876,15 +1668,6 @@ const REPARTITION_FREQ_IN_CHECKPOINT_DISTANCE: u64 = 10;

 // Private functions
 impl Timeline {
-    #[allow(dead_code)]
-    pub(crate) fn get_switch_to_aux_file_v2(&self) -> bool {
-        let tenant_conf = self.tenant_conf.load();
-        tenant_conf
-            .tenant_conf
-            .switch_to_aux_file_v2
-            .unwrap_or(self.conf.default_tenant_conf.switch_to_aux_file_v2)
-    }
-
    pub(crate) fn get_lazy_slru_download(&self) -> bool {
        let tenant_conf = self.tenant_conf.load();
        tenant_conf
@@ -2109,10 +1892,7 @@ impl Timeline {
                last_image_layer_creation_check_at: AtomicLsn::new(0),

                last_received_wal: Mutex::new(None),
-                rel_size_cache: RwLock::new(RelSizeCache {
-                    complete_as_of: disk_consistent_lsn,
-                    map: HashMap::new(),
-                }),
+                rel_size_cache: RwLock::new(HashMap::new()),

                download_all_remote_layers_task_info: RwLock::new(None),

@@ -2912,7 +2692,7 @@ impl Timeline {
    }
 }

-type TraversalId = Arc<str>;
+type TraversalId = String;

 trait TraversalLayerExt {
    fn traversal_id(&self) -> TraversalId;
@@ -2920,13 +2700,13 @@ trait TraversalLayerExt {

 impl TraversalLayerExt for Layer {
    fn traversal_id(&self) -> TraversalId {
-        Arc::clone(self.local_path_str())
+        self.local_path().to_string()
    }
 }

 impl TraversalLayerExt for Arc<InMemoryLayer> {
    fn traversal_id(&self) -> TraversalId {
-        Arc::clone(self.local_path_str())
+        format!("timeline {} in-memory {self}", self.get_timeline_id())
    }
 }

@@ -2955,7 +2735,7 @@ impl Timeline {
        let mut timeline = self;

        let mut read_count = scopeguard::guard(0, |cnt| {
-            crate::metrics::READ_NUM_LAYERS_VISITED.observe(cnt as f64)
+            crate::metrics::READ_NUM_FS_LAYERS.observe(cnt as f64)
        });

        // For debugging purposes, collect the path of layers that we traversed
@@ -2995,35 +2775,32 @@ impl Timeline {
                        if prev <= cont_lsn {
                            // Didn't make any progress in last iteration. Error out to avoid
                            // getting stuck in the loop.
-                            return Err(PageReconstructError::MissingKey(MissingKeyError {
-                                stuck_at_lsn: true,
+                            return Err(layer_traversal_error(format!(
+                                "could not find layer with more data for key {} at LSN {}, request LSN {}, ancestor {}",
                                key,
-                                shard: self.shard_identity.get_shard_number(&key),
-                                cont_lsn: Lsn(cont_lsn.0 - 1),
+                                Lsn(cont_lsn.0 - 1),
                                request_lsn,
-                                ancestor_lsn: Some(timeline.ancestor_lsn),
-                                traversal_path,
-                                backtrace: None,
-                            }));
+                                timeline.ancestor_lsn
+                            ), traversal_path));
                        }
                    }
                    prev_lsn = Some(cont_lsn);
                }
                ValueReconstructResult::Missing => {
-                    return Err(PageReconstructError::MissingKey(MissingKeyError {
-                        stuck_at_lsn: false,
-                        key,
-                        shard: self.shard_identity.get_shard_number(&key),
-                        cont_lsn,
-                        request_lsn,
-                        ancestor_lsn: None,
-                        traversal_path,
-                        backtrace: if cfg!(test) {
-                            Some(std::backtrace::Backtrace::force_capture())
+                    return Err(layer_traversal_error(
+                        if cfg!(test) {
+                            format!(
+                                "could not find data for key {} (shard {:?}) at LSN {}, for request at LSN {}\n{}",
+                                key, self.shard_identity.get_shard_number(&key), cont_lsn, request_lsn, std::backtrace::Backtrace::force_capture(),
+                            )
                        } else {
-                            None
+                            format!(
+                                "could not find data for key {} (shard {:?}) at LSN {}, for request at LSN {}",
+                                key, self.shard_identity.get_shard_number(&key), cont_lsn, request_lsn
+                            )
                        },
-                    }));
+                        traversal_path,
+                    ));
                }
            }

@@ -3070,8 +2847,12 @@ impl Timeline {
                        Err(e) => return Err(PageReconstructError::from(e)),
                    };
                    cont_lsn = lsn_floor;
-                    *read_count += 1;
-                    traversal_path.push((result, cont_lsn, open_layer.traversal_id()));
+                    // metrics: open_layer does not count as fs access, so we are not updating `read_count`
+                    traversal_path.push((
+                        result,
+                        cont_lsn,
+                        Box::new(move || open_layer.traversal_id()),
+                    ));
                    continue 'outer;
                }
            }
@@ -3097,8 +2878,12 @@ impl Timeline {
                        Err(e) => return Err(PageReconstructError::from(e)),
                    };
                    cont_lsn = lsn_floor;
-                    *read_count += 1;
-                    traversal_path.push((result, cont_lsn, frozen_layer.traversal_id()));
+                    // metrics: open_layer does not count as fs access, so we are not updating `read_count`
+                    traversal_path.push((
+                        result,
+                        cont_lsn,
+                        Box::new(move || frozen_layer.traversal_id()),
+                    ));
                    continue 'outer;
                }
            }
@@ -3119,7 +2904,14 @@ impl Timeline {
                };
                cont_lsn = lsn_floor;
                *read_count += 1;
-                traversal_path.push((result, cont_lsn, layer.traversal_id()));
+                traversal_path.push((
+                    result,
+                    cont_lsn,
+                    Box::new({
+                        let layer = layer.to_owned();
+                        move || layer.traversal_id()
+                    }),
+                ));
                continue 'outer;
            } else if timeline.ancestor_timeline.is_some() {
                // Nothing on this timeline. Traverse to parent
@@ -3172,42 +2964,7 @@ impl Timeline {
            .await?;

            keyspace.remove_overlapping_with(&completed);
-
-            // Do not descend into the ancestor timeline for aux files.
-            // We don't return a blanket [`GetVectoredError::MissingKey`] to avoid
-            // stalling compaction.
-            // TODO(chi): this will need to be updated for aux files v2 storage
-            if keyspace.overlaps(&NON_INHERITED_RANGE) {
-                let removed = keyspace.remove_overlapping_with(&KeySpace {
-                    ranges: vec![NON_INHERITED_RANGE],
-                });
-
-                for range in removed.ranges {
-                    let mut key = range.start;
-                    while key < range.end {
-                        reconstruct_state.on_key_error(
-                            key,
-                            PageReconstructError::MissingKey(MissingKeyError {
-                                stuck_at_lsn: false,
-                                key,
-                                shard: self.shard_identity.get_shard_number(&key),
-                                cont_lsn,
-                                request_lsn,
-                                ancestor_lsn: None,
-                                traversal_path: Vec::default(),
-                                backtrace: if cfg!(test) {
-                                    Some(std::backtrace::Backtrace::force_capture())
-                                } else {
-                                    None
-                                },
-                            }),
-                        );
-                        key = key.next();
-                    }
-                }
-            }
-
-            if keyspace.total_raw_size() == 0 || timeline.ancestor_timeline.is_none() {
+            if keyspace.total_size() == 0 || timeline.ancestor_timeline.is_none() {
                break;
            }

@@ -3220,7 +2977,7 @@ impl Timeline {
            timeline = &*timeline_owned;
        }

-        if keyspace.total_raw_size() != 0 {
+        if keyspace.total_size() != 0 {
            return Err(GetVectoredError::MissingKey(keyspace.start().unwrap()));
        }

@@ -3262,62 +3019,56 @@ impl Timeline {
            unmapped_keyspace.remove_overlapping_with(&keys_done_last_step);
            completed_keyspace.merge(&keys_done_last_step);

-            // Do not descent any further if the last layer we visited
-            // completed all keys in the keyspace it inspected. This is not
-            // required for correctness, but avoids visiting extra layers
-            // which turns out to be a perf bottleneck in some cases.
-            if !unmapped_keyspace.is_empty() {
-                let guard = timeline.layers.read().await;
-                let layers = guard.layer_map();
+            let guard = timeline.layers.read().await;
+            let layers = guard.layer_map();

-                let in_memory_layer = layers.find_in_memory_layer(|l| {
-                    let start_lsn = l.get_lsn_range().start;
-                    cont_lsn > start_lsn
-                });
+            let in_memory_layer = layers.find_in_memory_layer(|l| {
+                let start_lsn = l.get_lsn_range().start;
+                cont_lsn > start_lsn
+            });

-                match in_memory_layer {
-                    Some(l) => {
-                        let lsn_range = l.get_lsn_range().start..cont_lsn;
-                        fringe.update(
-                            ReadableLayer::InMemoryLayer(l),
-                            unmapped_keyspace.clone(),
-                            lsn_range,
-                        );
-                    }
-                    None => {
-                        for range in unmapped_keyspace.ranges.iter() {
-                            let results = layers.range_search(range.clone(), cont_lsn);
+            match in_memory_layer {
+                Some(l) => {
+                    let lsn_range = l.get_lsn_range().start..cont_lsn;
+                    fringe.update(
+                        ReadableLayer::InMemoryLayer(l),
+                        unmapped_keyspace.clone(),
+                        lsn_range,
+                    );
+                }
+                None => {
+                    for range in unmapped_keyspace.ranges.iter() {
+                        let results = layers.range_search(range.clone(), cont_lsn);

-                            results
-                                .found
-                                .into_iter()
-                                .map(|(SearchResult { layer, lsn_floor }, keyspace_accum)| {
-                                    (
-                                        ReadableLayer::PersistentLayer(guard.get_from_desc(&layer)),
-                                        keyspace_accum.to_keyspace(),
-                                        lsn_floor..cont_lsn,
-                                    )
-                                })
-                                .for_each(|(layer, keyspace, lsn_range)| {
-                                    fringe.update(layer, keyspace, lsn_range)
-                                });
-                        }
+                        results
+                            .found
+                            .into_iter()
+                            .map(|(SearchResult { layer, lsn_floor }, keyspace_accum)| {
+                                (
+                                    ReadableLayer::PersistentLayer(guard.get_from_desc(&layer)),
+                                    keyspace_accum.to_keyspace(),
+                                    lsn_floor..cont_lsn,
+                                )
+                            })
+                            .for_each(|(layer, keyspace, lsn_range)| {
+                                fringe.update(layer, keyspace, lsn_range)
+                            });
                    }
                }
-
-                // It's safe to drop the layer map lock after planning the next round of reads.
-                // The fringe keeps readable handles for the layers which are safe to read even
-                // if layers were compacted or flushed.
-                //
-                // The more interesting consideration is: "Why is the read algorithm still correct
-                // if the layer map changes while it is operating?". Doing a vectored read on a
-                // timeline boils down to pushing an imaginary lsn boundary downwards for each range
-                // covered by the read. The layer map tells us how to move the lsn downwards for a
-                // range at *a particular point in time*. It is fine for the answer to be different
-                // at two different time points.
-                drop(guard);
            }

+            // It's safe to drop the layer map lock after planning the next round of reads.
+            // The fringe keeps readable handles for the layers which are safe to read even
+            // if layers were compacted or flushed.
+            //
+            // The more interesting consideration is: "Why is the read algorithm still correct
+            // if the layer map changes while it is operating?". Doing a vectored read on a
+            // timeline boils down to pushing an imaginary lsn boundary downwards for each range
+            // covered by the read. The layer map tells us how to move the lsn downwards for a
+            // range at *a particular point in time*. It is fine for the answer to be different
+            // at two different time points.
+            drop(guard);
+
            if let Some((layer_to_read, keyspace_to_read, lsn_range)) = fringe.next_layer() {
                let next_cont_lsn = lsn_range.start;
                layer_to_read
@@ -3331,8 +3082,6 @@ impl Timeline {

                unmapped_keyspace = keyspace_to_read;
                cont_lsn = next_cont_lsn;
-
-                reconstruct_state.on_layer_visited();
            } else {
                break;
            }
@@ -3776,7 +3525,7 @@ impl Timeline {
        &self,
        disk_consistent_lsn: Lsn,
        layers_to_upload: impl IntoIterator<Item = ResidentLayer>,
-    ) -> anyhow::Result<()> {
+    ) -> anyhow::Result<TimelineMetadata> {
        // We can only save a valid 'prev_record_lsn' value on disk if we
        // flushed *all* in-memory changes to disk. We only track
        // 'prev_record_lsn' in memory for the latest processed record, so we
@@ -3793,10 +3542,19 @@ impl Timeline {
            None
        };

-        let update = crate::tenant::metadata::MetadataUpdate::new(
+        let ancestor_timeline_id = self
+            .ancestor_timeline
+            .as_ref()
+            .map(|ancestor| ancestor.timeline_id);
+
+        let metadata = TimelineMetadata::new(
            disk_consistent_lsn,
            ondisk_prev_record_lsn,
+            ancestor_timeline_id,
+            self.ancestor_lsn,
            *self.latest_gc_cutoff_lsn.read(),
+            self.initdb_lsn,
+            self.pg_version,
        );

        fail_point!("checkpoint-before-saving-metadata", |x| bail!(
@@ -3808,10 +3566,10 @@ impl Timeline {
            for layer in layers_to_upload {
                remote_client.schedule_layer_file_upload(layer)?;
            }
-            remote_client.schedule_index_upload_for_metadata_update(&update)?;
+            remote_client.schedule_index_upload_for_metadata_update(&metadata)?;
        }

-        Ok(())
+        Ok(metadata)
    }

    pub(crate) async fn preserve_initdb_archive(&self) -> anyhow::Result<()> {
@@ -3911,7 +3669,7 @@ impl Timeline {
        }

        let keyspace = self.collect_keyspace(lsn, ctx).await?;
-        let partitioning = keyspace.partition(&self.shard_identity, partition_size);
+        let partitioning = keyspace.partition(partition_size);

        *partitioning_guard = (partitioning, lsn);

@@ -3920,6 +3678,24 @@ impl Timeline {

    // Is it time to create a new image layer for the given partition?
    async fn time_for_new_image_layer(&self, partition: &KeySpace, lsn: Lsn) -> bool {
+        let last = self.last_image_layer_creation_check_at.load();
+        if lsn != Lsn(0) {
+            let distance = lsn
+                .checked_sub(last)
+                .expect("Attempt to compact with LSN going backwards");
+
+            let min_distance = self.get_image_layer_creation_check_threshold() as u64
+                * self.get_checkpoint_distance();
+
+            // Skip the expensive delta layer counting below if we've not ingested
+            // sufficient WAL since the last check.
+            if distance.0 < min_distance {
+                return false;
+            }
+        }
+
+        self.last_image_layer_creation_check_at.store(lsn);
+
        let threshold = self.get_image_creation_threshold();

        let guard = self.layers.read().await;
@@ -3991,37 +3767,9 @@ impl Timeline {
        // image layers  <100000000..100000099> and <200000000..200000199> are not completely covering it.
        let mut start = Key::MIN;

-        let check_for_image_layers = {
-            let last_checks_at = self.last_image_layer_creation_check_at.load();
-            let distance = lsn
-                .checked_sub(last_checks_at)
-                .expect("Attempt to compact with LSN going backwards");
-            let min_distance = self.get_image_layer_creation_check_threshold() as u64
-                * self.get_checkpoint_distance();
-
-            // Skip the expensive delta layer counting if this timeline has not ingested sufficient
-            // WAL since the last check.
-            distance.0 >= min_distance
-        };
-
-        if check_for_image_layers {
-            self.last_image_layer_creation_check_at.store(lsn);
-        }
-
        for partition in partitioning.parts.iter() {
            let img_range = start..partition.ranges.last().unwrap().end;
-
-            let do_it = if force {
-                true
-            } else if check_for_image_layers {
-                // [`Self::time_for_new_image_layer`] is CPU expensive,
-                // so skip if we've not collected enough WAL since the last time
-                self.time_for_new_image_layer(partition, lsn).await
-            } else {
-                false
-            };
-
-            if !do_it {
+            if !force && !self.time_for_new_image_layer(partition, lsn).await {
                start = img_range.end;
                continue;
            }
@@ -4064,7 +3812,7 @@ impl Timeline {
                    key = key.next();

                    // Maybe flush `key_rest_accum`
-                    if key_request_accum.raw_size() >= Timeline::MAX_GET_VECTORED_KEYS
+                    if key_request_accum.size() >= Timeline::MAX_GET_VECTORED_KEYS
                        || last_key_in_range
                    {
                        let results = self
@@ -4350,12 +4098,6 @@ impl Timeline {
        cancel: &CancellationToken,
        ctx: &RequestContext,
    ) -> anyhow::Result<()> {
-        let _timer = self
-            .metrics
-            .update_gc_info_histo
-            .start_timer()
-            .record_on_drop();
-
        // First, calculate pitr_cutoff_timestamp and then convert it to LSN.
        //
        // Some unit tests depend on garbage-collection working even when
@@ -4401,8 +4143,9 @@ impl Timeline {
                *self.get_latest_gc_cutoff_lsn()
            }
        } else {
-            // No time-based retention was configured. Interpret this as "keep no history".
-            self.get_last_record_lsn()
+            // No time-based retention was configured. Set time-based cutoff to
+            // same as LSN based.
+            cutoff_horizon
        };

        // Grab the lock and update the values
@@ -4922,7 +4665,35 @@ impl Timeline {
    }
 }

-type TraversalPathItem = (ValueReconstructResult, Lsn, TraversalId);
+type TraversalPathItem = (
+    ValueReconstructResult,
+    Lsn,
+    Box<dyn Send + FnOnce() -> TraversalId>,
+);
+
+/// Helper function for get_reconstruct_data() to add the path of layers traversed
+/// to an error, as anyhow context information.
+fn layer_traversal_error(msg: String, path: Vec<TraversalPathItem>) -> PageReconstructError {
+    // We want the original 'msg' to be the outermost context. The outermost context
+    // is the most high-level information, which also gets propagated to the client.
+    let mut msg_iter = path
+        .into_iter()
+        .map(|(r, c, l)| {
+            format!(
+                "layer traversal: result {:?}, cont_lsn {}, layer: {}",
+                r,
+                c,
+                l(),
+            )
+        })
+        .chain(std::iter::once(msg));
+    // Construct initial message from the first traversed layer
+    let err = anyhow!(msg_iter.next().unwrap());
+
+    // Append all subsequent traversals, and the error message 'msg', as contexts.
+    let msg = msg_iter.fold(err, |err, msg| err.context(msg));
+    PageReconstructError::from(msg)
+}

 struct TimelineWriterState {
    open_layer: Arc<InMemoryLayer>,
--- a/pageserver/src/tenant/timeline/compaction.rs
+++ b/pageserver/src/tenant/timeline/compaction.rs
@@ -15,7 +15,7 @@ use anyhow::{anyhow, Context};
 use enumset::EnumSet;
 use fail::fail_point;
 use itertools::Itertools;
-use pageserver_api::shard::{ShardIdentity, TenantShardId};
+use pageserver_api::shard::TenantShardId;
 use tokio_util::sync::CancellationToken;
 use tracing::{debug, info, info_span, trace, warn, Instrument};
 use utils::id::TimelineId;
@@ -831,10 +831,6 @@ impl CompactionJobExecutor for TimelineAdaptor {

    type RequestContext = crate::context::RequestContext;

-    fn get_shard_identity(&self) -> &ShardIdentity {
-        self.timeline.get_shard_identity()
-    }
-
    async fn get_layers(
        &mut self,
        key_range: &Range<Key>,
--- a/pageserver/src/tenant/timeline/eviction_task.rs
+++ b/pageserver/src/tenant/timeline/eviction_task.rs
@@ -188,10 +188,24 @@ impl Timeline {
    ) -> ControlFlow<()> {
        let now = SystemTime::now();

-        let permit = self.acquire_imitation_permit(cancel, ctx).await?;
+        let acquire_permit = crate::tenant::tasks::concurrent_background_tasks_rate_limit_permit(
+            BackgroundLoopKind::Eviction,
+            ctx,
+        );

-        self.imitate_layer_accesses(tenant, p, cancel, gate, permit, ctx)
-            .await?;
+        let _permit = tokio::select! {
+            permit = acquire_permit => permit,
+            _ = cancel.cancelled() => return ControlFlow::Break(()),
+            _ = self.cancel.cancelled() => return ControlFlow::Break(()),
+        };
+
+        match self
+            .imitate_layer_accesses(tenant, p, cancel, gate, ctx)
+            .await
+        {
+            ControlFlow::Break(()) => return ControlFlow::Break(()),
+            ControlFlow::Continue(()) => (),
+        }

        #[derive(Debug, Default)]
        struct EvictionStats {
@@ -316,27 +330,19 @@ impl Timeline {
        gate: &GateGuard,
        ctx: &RequestContext,
    ) -> ControlFlow<()> {
-        let permit = self.acquire_imitation_permit(cancel, ctx).await?;
-
-        self.imitate_layer_accesses(tenant, p, cancel, gate, permit, ctx)
-            .await
-    }
-
-    async fn acquire_imitation_permit(
-        &self,
-        cancel: &CancellationToken,
-        ctx: &RequestContext,
-    ) -> ControlFlow<(), tokio::sync::SemaphorePermit<'static>> {
        let acquire_permit = crate::tenant::tasks::concurrent_background_tasks_rate_limit_permit(
            BackgroundLoopKind::Eviction,
            ctx,
        );

-        tokio::select! {
-            permit = acquire_permit => ControlFlow::Continue(permit),
-            _ = cancel.cancelled() => ControlFlow::Break(()),
-            _ = self.cancel.cancelled() => ControlFlow::Break(()),
-        }
+        let _permit = tokio::select! {
+            permit = acquire_permit => permit,
+            _ = cancel.cancelled() => return ControlFlow::Break(()),
+            _ = self.cancel.cancelled() => return ControlFlow::Break(()),
+        };
+
+        self.imitate_layer_accesses(tenant, p, cancel, gate, ctx)
+            .await
    }

    /// If we evict layers but keep cached values derived from those layers, then
@@ -370,7 +376,6 @@ impl Timeline {
        p: &EvictionPolicyLayerAccessThreshold,
        cancel: &CancellationToken,
        gate: &GateGuard,
-        permit: tokio::sync::SemaphorePermit<'static>,
        ctx: &RequestContext,
    ) -> ControlFlow<()> {
        if !self.tenant_shard_id.is_shard_zero() {
@@ -403,28 +408,7 @@ impl Timeline {
        // Make one of the tenant's timelines draw the short straw and run the calculation.
        // The others wait until the calculation is done so that they take into account the
        // imitated accesses that the winner made.
-        let (mut state, _permit) = {
-            if let Ok(locked) = tenant.eviction_task_tenant_state.try_lock() {
-                (locked, permit)
-            } else {
-                // we might need to wait for a long time here in case of pathological synthetic
-                // size calculation performance
-                drop(permit);
-                let locked = tokio::select! {
-                    locked = tenant.eviction_task_tenant_state.lock() => locked,
-                    _ = self.cancel.cancelled() => {
-                        return ControlFlow::Break(())
-                    },
-                    _ = cancel.cancelled() => {
-                        return ControlFlow::Break(())
-                    }
-                };
-                // then reacquire -- this will be bad if there is a lot of traffic, but because we
-                // released the permit, the overall latency will be much better.
-                let permit = self.acquire_imitation_permit(cancel, ctx).await?;
-                (locked, permit)
-            }
-        };
+        let mut state = tenant.eviction_task_tenant_state.lock().await;
        match state.last_layer_access_imitation {
            Some(ts) if ts.elapsed() < inter_imitate_period => { /* no need to run */ }
            _ => {
--- a/pageserver/src/virtual_file.rs
+++ b/pageserver/src/virtual_file.rs
@@ -32,11 +32,11 @@ pub use io_engine::feature_test as io_engine_feature_test;
 pub use io_engine::FeatureTestResult as IoEngineFeatureTestResult;
 mod metadata;
 mod open_options;
-use self::owned_buffers_io::write::OwnedAsyncWriter;
 pub(crate) use io_engine::IoEngineKind;
 pub(crate) use metadata::Metadata;
 pub(crate) use open_options::*;

+#[cfg_attr(not(target_os = "linux"), allow(dead_code))]
 pub(crate) mod owned_buffers_io {
    //! Abstractions for IO with owned buffers.
    //!
@@ -1083,17 +1083,6 @@ impl Drop for VirtualFile {
    }
 }

-impl OwnedAsyncWriter for VirtualFile {
-    #[inline(always)]
-    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
-        &mut self,
-        buf: B,
-    ) -> std::io::Result<(usize, B::Buf)> {
-        let (buf, res) = VirtualFile::write_all(self, buf).await;
-        res.map(move |v| (v, buf))
-    }
-}
-
 impl OpenFiles {
    fn new(num_slots: usize) -> OpenFiles {
        let mut slots = Box::new(Vec::with_capacity(num_slots));
--- a/pageserver/src/virtual_file/owned_buffers_io/util/size_tracking_writer.rs
+++ b/pageserver/src/virtual_file/owned_buffers_io/util/size_tracking_writer.rs
@@ -1,45 +1,33 @@
-use crate::virtual_file::owned_buffers_io::write::OwnedAsyncWriter;
+use crate::virtual_file::{owned_buffers_io::write::OwnedAsyncWriter, VirtualFile};
 use tokio_epoll_uring::{BoundedBuf, IoBuf};

-pub struct Writer<W> {
-    dst: W,
+pub struct Writer {
+    dst: VirtualFile,
    bytes_amount: u64,
 }

-impl<W> Writer<W> {
-    pub fn new(dst: W) -> Self {
+impl Writer {
+    pub fn new(dst: VirtualFile) -> Self {
        Self {
            dst,
            bytes_amount: 0,
        }
    }
-
-    pub fn bytes_written(&self) -> u64 {
-        self.bytes_amount
-    }
-
-    pub fn as_inner(&self) -> &W {
-        &self.dst
-    }
-
    /// Returns the wrapped `VirtualFile` object as well as the number
    /// of bytes that were written to it through this object.
-    #[cfg_attr(target_os = "macos", allow(dead_code))]
-    pub fn into_inner(self) -> (u64, W) {
+    pub fn into_inner(self) -> (u64, VirtualFile) {
        (self.bytes_amount, self.dst)
    }
 }

-impl<W> OwnedAsyncWriter for Writer<W>
-where
-    W: OwnedAsyncWriter,
-{
+impl OwnedAsyncWriter for Writer {
    #[inline(always)]
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
    ) -> std::io::Result<(usize, B::Buf)> {
-        let (nwritten, buf) = self.dst.write_all(buf).await?;
+        let (buf, res) = self.dst.write_all(buf).await;
+        let nwritten = res?;
        self.bytes_amount += u64::try_from(nwritten).unwrap();
        Ok((nwritten, buf))
    }
--- a/pageserver/src/virtual_file/owned_buffers_io/write.rs
+++ b/pageserver/src/virtual_file/owned_buffers_io/write.rs
@@ -10,14 +10,14 @@ pub trait OwnedAsyncWriter {
    ) -> std::io::Result<(usize, B::Buf)>;
 }

-/// A wrapper aorund an [`OwnedAsyncWriter`] that uses a [`Buffer`] to batch
-/// small writes into larger writes of size [`Buffer::cap`].
+/// A wrapper aorund an [`OwnedAsyncWriter`] that batches smaller writers
+/// into `BUFFER_SIZE`-sized writes.
 ///
 /// # Passthrough Of Large Writers
 ///
-/// Calls to [`BufferedWriter::write_buffered`] that are larger than [`Buffer::cap`]
-/// cause the internal buffer to be flushed prematurely so that the large
-/// buffered write is passed through to the underlying [`OwnedAsyncWriter`].
+/// Buffered writes larger than the `BUFFER_SIZE` cause the internal
+/// buffer to be flushed, even if it is not full yet. Then, the large
+/// buffered write is passed through to the unerlying [`OwnedAsyncWriter`].
 ///
 /// This pass-through is generally beneficial for throughput, but if
 /// the storage backend of the [`OwnedAsyncWriter`] is a shared resource,
@@ -25,38 +25,27 @@ pub trait OwnedAsyncWriter {
 ///
 /// In such cases, a different implementation that always buffers in memory
 /// may be preferable.
-pub struct BufferedWriter<B, W> {
+pub struct BufferedWriter<const BUFFER_SIZE: usize, W> {
    writer: W,
-    /// invariant: always remains Some(buf) except
-    /// - while IO is ongoing => goes back to Some() once the IO completed successfully
-    /// - after an IO error => stays `None` forever
-    /// In these exceptional cases, it's `None`.
-    buf: Option<B>,
+    // invariant: always remains Some(buf)
+    // with buf.capacity() == BUFFER_SIZE except
+    // - while IO is ongoing => goes back to Some() once the IO completed successfully
+    // - after an IO error => stays `None` forever
+    // In these exceptional cases, it's `None`.
+    buf: Option<BytesMut>,
 }

-impl<B, Buf, W> BufferedWriter<B, W>
+impl<const BUFFER_SIZE: usize, W> BufferedWriter<BUFFER_SIZE, W>
 where
-    B: Buffer<IoBuf = Buf> + Send,
-    Buf: IoBuf + Send,
    W: OwnedAsyncWriter,
 {
-    pub fn new(writer: W, buf: B) -> Self {
+    pub fn new(writer: W) -> Self {
        Self {
            writer,
-            buf: Some(buf),
+            buf: Some(BytesMut::with_capacity(BUFFER_SIZE)),
        }
    }

-    pub fn as_inner(&self) -> &W {
-        &self.writer
-    }
-
-    /// Panics if used after any of the write paths returned an error
-    pub fn inspect_buffer(&self) -> &B {
-        self.buf()
-    }
-
-    #[cfg_attr(target_os = "macos", allow(dead_code))]
    pub async fn flush_and_into_inner(mut self) -> std::io::Result<W> {
        self.flush().await?;
        let Self { buf, writer } = self;
@@ -64,144 +53,61 @@ where
        Ok(writer)
    }

-    #[inline(always)]
-    fn buf(&self) -> &B {
-        self.buf
-            .as_ref()
-            .expect("must not use after we returned an error")
-    }
-
-    #[cfg_attr(target_os = "macos", allow(dead_code))]
-    pub async fn write_buffered<S: IoBuf>(&mut self, chunk: Slice<S>) -> std::io::Result<(usize, S)>
+    pub async fn write_buffered<B: IoBuf>(&mut self, chunk: Slice<B>) -> std::io::Result<()>
    where
-        S: IoBuf + Send,
+        B: IoBuf + Send,
    {
-        let chunk_len = chunk.len();
        // avoid memcpy for the middle of the chunk
-        if chunk.len() >= self.buf().cap() {
+        if chunk.len() >= BUFFER_SIZE {
            self.flush().await?;
            // do a big write, bypassing `buf`
            assert_eq!(
                self.buf
                    .as_ref()
                    .expect("must not use after an error")
-                    .pending(),
+                    .len(),
                0
            );
+            let chunk_len = chunk.len();
            let (nwritten, chunk) = self.writer.write_all(chunk).await?;
            assert_eq!(nwritten, chunk_len);
-            return Ok((nwritten, chunk));
+            drop(chunk);
+            return Ok(());
        }
        // in-memory copy the < BUFFER_SIZED tail of the chunk
-        assert!(chunk.len() < self.buf().cap());
-        let mut slice = &chunk[..];
-        while !slice.is_empty() {
-            let buf = self.buf.as_mut().expect("must not use after an error");
-            let need = buf.cap() - buf.pending();
-            let have = slice.len();
-            let n = std::cmp::min(need, have);
-            buf.extend_from_slice(&slice[..n]);
-            slice = &slice[n..];
-            if buf.pending() >= buf.cap() {
-                assert_eq!(buf.pending(), buf.cap());
-                self.flush().await?;
-            }
-        }
-        assert!(slice.is_empty(), "by now we should have drained the chunk");
-        Ok((chunk_len, chunk.into_inner()))
-    }
-
-    /// Strictly less performant variant of [`Self::write_buffered`] that allows writing borrowed data.
-    ///
-    /// It is less performant because we always have to copy the borrowed data into the internal buffer
-    /// before we can do the IO. The [`Self::write_buffered`] can avoid this, which is more performant
-    /// for large writes.
-    pub async fn write_buffered_borrowed(&mut self, mut chunk: &[u8]) -> std::io::Result<usize> {
-        let chunk_len = chunk.len();
+        assert!(chunk.len() < BUFFER_SIZE);
+        let mut chunk = &chunk[..];
        while !chunk.is_empty() {
            let buf = self.buf.as_mut().expect("must not use after an error");
-            let need = buf.cap() - buf.pending();
+            let need = BUFFER_SIZE - buf.len();
            let have = chunk.len();
            let n = std::cmp::min(need, have);
            buf.extend_from_slice(&chunk[..n]);
            chunk = &chunk[n..];
-            if buf.pending() >= buf.cap() {
-                assert_eq!(buf.pending(), buf.cap());
+            if buf.len() >= BUFFER_SIZE {
+                assert_eq!(buf.len(), BUFFER_SIZE);
                self.flush().await?;
            }
        }
-        Ok(chunk_len)
+        assert!(chunk.is_empty(), "by now we should have drained the chunk");
+        Ok(())
    }

    async fn flush(&mut self) -> std::io::Result<()> {
        let buf = self.buf.take().expect("must not use after an error");
-        let buf_len = buf.pending();
-        if buf_len == 0 {
+        if buf.is_empty() {
            self.buf = Some(buf);
-            return Ok(());
+            return std::io::Result::Ok(());
        }
-        let (nwritten, io_buf) = self.writer.write_all(buf.flush()).await?;
+        let buf_len = buf.len();
+        let (nwritten, mut buf) = self.writer.write_all(buf).await?;
        assert_eq!(nwritten, buf_len);
-        self.buf = Some(Buffer::reuse_after_flush(io_buf));
+        buf.clear();
+        self.buf = Some(buf);
        Ok(())
    }
 }

-/// A [`Buffer`] is used by [`BufferedWriter`] to batch smaller writes into larger ones.
-pub trait Buffer {
-    type IoBuf: IoBuf;
-
-    /// Capacity of the buffer. Must not change over the lifetime `self`.`
-    fn cap(&self) -> usize;
-
-    /// Add data to the buffer.
-    /// Panics if there is not enough room to accomodate `other`'s content, i.e.,
-    /// panics if `other.len() > self.cap() - self.pending()`.
-    fn extend_from_slice(&mut self, other: &[u8]);
-
-    /// Number of bytes in the buffer.
-    fn pending(&self) -> usize;
-
-    /// Turns `self` into a [`tokio_epoll_uring::Slice`] of the pending data
-    /// so we can use [`tokio_epoll_uring`] to write it to disk.
-    fn flush(self) -> Slice<Self::IoBuf>;
-
-    /// After the write to disk is done and we have gotten back the slice,
-    /// [`BufferedWriter`] uses this method to re-use the io buffer.
-    fn reuse_after_flush(iobuf: Self::IoBuf) -> Self;
-}
-
-impl Buffer for BytesMut {
-    type IoBuf = BytesMut;
-
-    #[inline(always)]
-    fn cap(&self) -> usize {
-        self.capacity()
-    }
-
-    fn extend_from_slice(&mut self, other: &[u8]) {
-        BytesMut::extend_from_slice(self, other)
-    }
-
-    #[inline(always)]
-    fn pending(&self) -> usize {
-        self.len()
-    }
-
-    fn flush(self) -> Slice<BytesMut> {
-        if self.is_empty() {
-            return self.slice_full();
-        }
-        let len = self.len();
-        self.slice(0..len)
-    }
-
-    fn reuse_after_flush(mut iobuf: BytesMut) -> Self {
-        iobuf.clear();
-        iobuf
-    }
-}
-
 impl OwnedAsyncWriter for Vec<u8> {
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
@@ -219,8 +125,6 @@ impl OwnedAsyncWriter for Vec<u8> {

 #[cfg(test)]
 mod tests {
-    use bytes::BytesMut;
-
    use super::*;

    #[derive(Default)]
@@ -254,7 +158,7 @@ mod tests {
    #[tokio::test]
    async fn test_buffered_writes_only() -> std::io::Result<()> {
        let recorder = RecorderWriter::default();
-        let mut writer = BufferedWriter::new(recorder, BytesMut::with_capacity(2));
+        let mut writer = BufferedWriter::<2, _>::new(recorder);
        write!(writer, b"a");
        write!(writer, b"b");
        write!(writer, b"c");
@@ -271,7 +175,7 @@ mod tests {
    #[tokio::test]
    async fn test_passthrough_writes_only() -> std::io::Result<()> {
        let recorder = RecorderWriter::default();
-        let mut writer = BufferedWriter::new(recorder, BytesMut::with_capacity(2));
+        let mut writer = BufferedWriter::<2, _>::new(recorder);
        write!(writer, b"abc");
        write!(writer, b"de");
        write!(writer, b"");
@@ -287,7 +191,7 @@ mod tests {
    #[tokio::test]
    async fn test_passthrough_write_with_nonempty_buffer() -> std::io::Result<()> {
        let recorder = RecorderWriter::default();
-        let mut writer = BufferedWriter::new(recorder, BytesMut::with_capacity(2));
+        let mut writer = BufferedWriter::<2, _>::new(recorder);
        write!(writer, b"a");
        write!(writer, b"bc");
        write!(writer, b"d");
@@ -299,31 +203,4 @@ mod tests {
        );
        Ok(())
    }
-
-    #[tokio::test]
-    async fn test_write_all_borrowed_always_goes_through_buffer() -> std::io::Result<()> {
-        let recorder = RecorderWriter::default();
-        let mut writer = BufferedWriter::new(recorder, BytesMut::with_capacity(2));
-
-        writer.write_buffered_borrowed(b"abc").await?;
-        writer.write_buffered_borrowed(b"d").await?;
-        writer.write_buffered_borrowed(b"e").await?;
-        writer.write_buffered_borrowed(b"fg").await?;
-        writer.write_buffered_borrowed(b"hi").await?;
-        writer.write_buffered_borrowed(b"j").await?;
-        writer.write_buffered_borrowed(b"klmno").await?;
-
-        let recorder = writer.flush_and_into_inner().await?;
-        assert_eq!(
-            recorder.writes,
-            {
-                let expect: &[&[u8]] = &[b"ab", b"cd", b"ef", b"gh", b"ij", b"kl", b"mn", b"o"];
-                expect
-            }
-            .iter()
-            .map(|v| v[..].to_vec())
-            .collect::<Vec<_>>()
-        );
-        Ok(())
-    }
 }
--- a/pageserver/src/walingest.rs
+++ b/pageserver/src/walingest.rs
@@ -1034,7 +1034,7 @@ impl WalIngest {

            let nblocks = modification
                .tline
-                .get_rel_size(src_rel, Version::Modified(modification), ctx)
+                .get_rel_size(src_rel, Version::Modified(modification), true, ctx)
                .await?;
            let dst_rel = RelTag {
                spcnode: tablespace_id,
@@ -1068,7 +1068,13 @@ impl WalIngest {

                let content = modification
                    .tline
-                    .get_rel_page_at_lsn(src_rel, blknum, Version::Modified(modification), ctx)
+                    .get_rel_page_at_lsn(
+                        src_rel,
+                        blknum,
+                        Version::Modified(modification),
+                        true,
+                        ctx,
+                    )
                    .await?;
                modification.put_rel_page_image(dst_rel, blknum, content)?;
                num_blocks_copied += 1;
@@ -1236,7 +1242,7 @@ impl WalIngest {
                };
                if modification
                    .tline
-                    .get_rel_exists(rel, Version::Modified(modification), ctx)
+                    .get_rel_exists(rel, Version::Modified(modification), true, ctx)
                    .await?
                {
                    self.put_rel_drop(modification, rel, ctx).await?;
@@ -1535,7 +1541,7 @@ impl WalIngest {
            nblocks
        } else if !modification
            .tline
-            .get_rel_exists(rel, Version::Modified(modification), ctx)
+            .get_rel_exists(rel, Version::Modified(modification), true, ctx)
            .await?
        {
            // create it with 0 size initially, the logic below will extend it
@@ -1547,7 +1553,7 @@ impl WalIngest {
        } else {
            modification
                .tline
-                .get_rel_size(rel, Version::Modified(modification), ctx)
+                .get_rel_size(rel, Version::Modified(modification), true, ctx)
                .await?
        };

@@ -1644,14 +1650,14 @@ async fn get_relsize(
 ) -> anyhow::Result<BlockNumber> {
    let nblocks = if !modification
        .tline
-        .get_rel_exists(rel, Version::Modified(modification), ctx)
+        .get_rel_exists(rel, Version::Modified(modification), true, ctx)
        .await?
    {
        0
    } else {
        modification
            .tline
-            .get_rel_size(rel, Version::Modified(modification), ctx)
+            .get_rel_size(rel, Version::Modified(modification), true, ctx)
            .await?
    };
    Ok(nblocks)
@@ -1726,29 +1732,29 @@ mod tests {
        // The relation was created at LSN 2, not visible at LSN 1 yet.
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x10)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x10)), false, &ctx)
                .await?,
            false
        );
        assert!(tline
-            .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x10)), &ctx)
+            .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x10)), false, &ctx)
            .await
            .is_err());
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            true
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            1
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            3
        );
@@ -1756,46 +1762,46 @@ mod tests {
        // Check page contents at each LSN
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            test_img("foo blk 0 at 2")
        );

        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x30)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x30)), false, &ctx)
                .await?,
            test_img("foo blk 0 at 3")
        );

        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x40)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x40)), false, &ctx)
                .await?,
            test_img("foo blk 0 at 3")
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x40)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x40)), false, &ctx)
                .await?,
            test_img("foo blk 1 at 4")
        );

        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            test_img("foo blk 0 at 3")
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            test_img("foo blk 1 at 4")
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 2, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 2, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            test_img("foo blk 2 at 5")
        );
@@ -1811,19 +1817,19 @@ mod tests {
        // Check reported size and contents after truncation
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x60)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x60)), false, &ctx)
                .await?,
            2
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x60)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x60)), false, &ctx)
                .await?,
            test_img("foo blk 0 at 3")
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x60)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x60)), false, &ctx)
                .await?,
            test_img("foo blk 1 at 4")
        );
@@ -1831,13 +1837,13 @@ mod tests {
        // should still see the truncated block with older LSN
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            3
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 2, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 2, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            test_img("foo blk 2 at 5")
        );
@@ -1850,7 +1856,7 @@ mod tests {
        m.commit(&ctx).await?;
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x68)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x68)), false, &ctx)
                .await?,
            0
        );
@@ -1863,19 +1869,19 @@ mod tests {
        m.commit(&ctx).await?;
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x70)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x70)), false, &ctx)
                .await?,
            2
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x70)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 0, Version::Lsn(Lsn(0x70)), false, &ctx)
                .await?,
            ZERO_PAGE
        );
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x70)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 1, Version::Lsn(Lsn(0x70)), false, &ctx)
                .await?,
            test_img("foo blk 1")
        );
@@ -1888,21 +1894,21 @@ mod tests {
        m.commit(&ctx).await?;
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x80)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x80)), false, &ctx)
                .await?,
            1501
        );
        for blk in 2..1500 {
            assert_eq!(
                tline
-                    .get_rel_page_at_lsn(TESTREL_A, blk, Version::Lsn(Lsn(0x80)), &ctx)
+                    .get_rel_page_at_lsn(TESTREL_A, blk, Version::Lsn(Lsn(0x80)), false, &ctx)
                    .await?,
                ZERO_PAGE
            );
        }
        assert_eq!(
            tline
-                .get_rel_page_at_lsn(TESTREL_A, 1500, Version::Lsn(Lsn(0x80)), &ctx)
+                .get_rel_page_at_lsn(TESTREL_A, 1500, Version::Lsn(Lsn(0x80)), false, &ctx)
                .await?,
            test_img("foo blk 1500")
        );
@@ -1929,13 +1935,13 @@ mod tests {
        // Check that rel exists and size is correct
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            true
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            1
        );
@@ -1948,7 +1954,7 @@ mod tests {
        // Check that rel is not visible anymore
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x30)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x30)), false, &ctx)
                .await?,
            false
        );
@@ -1966,13 +1972,13 @@ mod tests {
        // Check that rel exists and size is correct
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x40)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x40)), false, &ctx)
                .await?,
            true
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x40)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x40)), false, &ctx)
                .await?,
            1
        );
@@ -2005,24 +2011,24 @@ mod tests {
        // The relation was created at LSN 20, not visible at LSN 1 yet.
        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x10)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x10)), false, &ctx)
                .await?,
            false
        );
        assert!(tline
-            .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x10)), &ctx)
+            .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x10)), false, &ctx)
            .await
            .is_err());

        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            true
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x20)), false, &ctx)
                .await?,
            relsize
        );
@@ -2033,7 +2039,7 @@ mod tests {
            let data = format!("foo blk {} at {}", blkno, lsn);
            assert_eq!(
                tline
-                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(lsn), &ctx)
+                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(lsn), false, &ctx)
                    .await?,
                test_img(&data)
            );
@@ -2050,7 +2056,7 @@ mod tests {
        // Check reported size and contents after truncation
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x60)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x60)), false, &ctx)
                .await?,
            1
        );
@@ -2060,7 +2066,7 @@ mod tests {
            let data = format!("foo blk {} at {}", blkno, lsn);
            assert_eq!(
                tline
-                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x60)), &ctx)
+                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x60)), false, &ctx)
                    .await?,
                test_img(&data)
            );
@@ -2069,7 +2075,7 @@ mod tests {
        // should still see all blocks with older LSN
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x50)), false, &ctx)
                .await?,
            relsize
        );
@@ -2078,7 +2084,7 @@ mod tests {
            let data = format!("foo blk {} at {}", blkno, lsn);
            assert_eq!(
                tline
-                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x50)), &ctx)
+                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x50)), false, &ctx)
                    .await?,
                test_img(&data)
            );
@@ -2098,13 +2104,13 @@ mod tests {

        assert_eq!(
            tline
-                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x80)), &ctx)
+                .get_rel_exists(TESTREL_A, Version::Lsn(Lsn(0x80)), false, &ctx)
                .await?,
            true
        );
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x80)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(0x80)), false, &ctx)
                .await?,
            relsize
        );
@@ -2114,7 +2120,7 @@ mod tests {
            let data = format!("foo blk {} at {}", blkno, lsn);
            assert_eq!(
                tline
-                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x80)), &ctx)
+                    .get_rel_page_at_lsn(TESTREL_A, blkno, Version::Lsn(Lsn(0x80)), false, &ctx)
                    .await?,
                test_img(&data)
            );
@@ -2148,7 +2154,7 @@ mod tests {

        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), false, &ctx)
                .await?,
            RELSEG_SIZE + 1
        );
@@ -2162,7 +2168,7 @@ mod tests {
        m.commit(&ctx).await?;
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), false, &ctx)
                .await?,
            RELSEG_SIZE
        );
@@ -2177,7 +2183,7 @@ mod tests {
        m.commit(&ctx).await?;
        assert_eq!(
            tline
-                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), &ctx)
+                .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), false, &ctx)
                .await?,
            RELSEG_SIZE - 1
        );
@@ -2195,7 +2201,7 @@ mod tests {
            m.commit(&ctx).await?;
            assert_eq!(
                tline
-                    .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), &ctx)
+                    .get_rel_size(TESTREL_A, Version::Lsn(Lsn(lsn)), false, &ctx)
                    .await?,
                size as BlockNumber
            );
--- a/pgxn/neon/libpagestore.c
+++ b/pgxn/neon/libpagestore.c
@@ -49,8 +49,6 @@ char	   *neon_auth_token;
 int			readahead_buffer_size = 128;
 int			flush_every_n_requests = 8;

-int         neon_protocol_version = 1;
-
 static int	n_reconnect_attempts = 0;
 static int	max_reconnect_attempts = 60;
 static int	stripe_size;
@@ -381,17 +379,7 @@ pageserver_connect(shardno_t shard_no, int elevel)
 		pfree(msg);
 		return false;
 	}
-	switch (neon_protocol_version)
-	{
-		case 2:
-			query = psprintf("pagestream_v2 %s %s", neon_tenant, neon_timeline);
-			break;
-		case 1:
-			query = psprintf("pagestream %s %s", neon_tenant, neon_timeline);
-			break;
-		default:
-			elog(ERROR, "unexpected neon_protocol_version %d", neon_protocol_version);
-	}
+	query = psprintf("pagestream %s %s", neon_tenant, neon_timeline);
 	ret = PQsendQuery(conn, query);
 	pfree(query);
 	if (ret != 1)
@@ -452,7 +440,7 @@ pageserver_connect(shardno_t shard_no, int elevel)
 		return false;
 	}

-	neon_shard_log(shard_no, LOG, "libpagestore: connected to '%s' with protocol version %d", connstr, neon_protocol_version);
+	neon_shard_log(shard_no, LOG, "libpagestore: connected to '%s'", connstr);
 	page_servers[shard_no].conn = conn;
 	page_servers[shard_no].wes = wes;

@@ -856,16 +844,6 @@ pg_init_libpagestore(void)
 							PGC_USERSET,
 							0,	/* no flags required */
 							NULL, (GucIntAssignHook) &readahead_buffer_resize, NULL);
-	DefineCustomIntVariable("neon.protocol_version",
-							"Version of compute<->page server protocol",
-							NULL,
-							&neon_protocol_version,
-							1, /* default to old protocol for now */
-							1, /* min */
-							2, /* max */
-							PGC_SU_BACKEND,
-							0,	/* no flags required */
-							NULL, NULL, NULL);

 	relsize_hash_init();

--- a/pgxn/neon/pagestore_client.h
+++ b/pgxn/neon/pagestore_client.h
@@ -69,33 +69,18 @@ typedef enum {
 	SLRU_MULTIXACT_OFFSETS
 } SlruKind;

-/*--
- * supertype of all the Neon*Request structs below.
+/*
+ * supertype of all the Neon*Request structs below
 *
- * All requests contain two LSNs:
- *
- * lsn:                request page (or relation size, etc) at this LSN
- * not_modified_since: Hint that the page hasn't been modified between
- *                     this LSN and the request LSN (`lsn`).
- *
- * To request the latest version of a page, you can use MAX_LSN as the request
- * LSN.
- *
- * If you don't know any better, you can always set 'not_modified_since' equal
- * to 'lsn', but providing a lower value can speed up processing the request
- * in the pageserver, as it doesn't need to wait for the WAL to arrive, and it
- * can skip traversing through recent layers which we know to not contain any
- * versions for the requested page.
- *
- * These structs describe the V2 of these requests. The old V1 protocol contained
- * just one LSN and a boolean 'latest' flag. If the neon_protocol_version GUC is
- * set to 1, we will convert these to the V1 requests before sending.
+ * If 'latest' is true, we are requesting the latest page version, and 'lsn'
+ * is just a hint to the server that we know there are no versions of the page
+ * (or relation size, for exists/nblocks requests) later than the 'lsn'.
 */
 typedef struct
 {
 	NeonMessageTag tag;
-	XLogRecPtr	lsn;
-	XLogRecPtr	not_modified_since;
+	bool		latest;			/* if true, request latest page version */
+	XLogRecPtr	lsn;			/* request page version @ this LSN */
 } NeonRequest;

 typedef struct
@@ -208,7 +193,6 @@ extern int	readahead_buffer_size;
 extern char *neon_timeline;
 extern char *neon_tenant;
 extern int32 max_cluster_size;
-extern int  neon_protocol_version;

 extern shardno_t get_shard_number(BufferTag* tag);

@@ -241,14 +225,14 @@ extern bool neon_prefetch(SMgrRelation reln, ForkNumber forknum,
 extern void neon_read(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 					  char *buffer);
 extern PGDLLEXPORT void neon_read_at_lsn(NRelFileInfo rnode, ForkNumber forkNum, BlockNumber blkno,
-										 XLogRecPtr request_lsn, XLogRecPtr not_modified_since, char *buffer);
+										 XLogRecPtr request_lsn, bool request_latest, char *buffer);
 extern void neon_write(SMgrRelation reln, ForkNumber forknum,
 					   BlockNumber blocknum, char *buffer, bool skipFsync);
 #else
 extern void neon_read(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 					  void *buffer);
 extern PGDLLEXPORT void neon_read_at_lsn(NRelFileInfo rnode, ForkNumber forkNum, BlockNumber blkno,
-										 XLogRecPtr request_lsn, XLogRecPtr not_modified_since, void *buffer);
+										 XLogRecPtr request_lsn, bool request_latest, void *buffer);
 extern void neon_write(SMgrRelation reln, ForkNumber forknum,
 					   BlockNumber blocknum, const void *buffer, bool skipFsync);
 #endif
--- a/pgxn/neon/pagestore_smgr.c
+++ b/pgxn/neon/pagestore_smgr.c
@@ -168,8 +168,8 @@ typedef enum PrefetchStatus
 typedef struct PrefetchRequest
 {
 	BufferTag	buftag;			/* must be first entry in the struct */
-	XLogRecPtr	request_lsn;
-	XLogRecPtr	not_modified_since;
+	XLogRecPtr	effective_request_lsn;
+	XLogRecPtr	actual_request_lsn;
 	NeonResponse *response;		/* may be null */
 	PrefetchStatus status;
 	shardno_t   shard_no;
@@ -269,19 +269,19 @@ static PrefetchState *MyPState;
 	) \
 )

+static XLogRecPtr prefetch_lsn = 0;
+
 static bool compact_prefetch_buffers(void);
 static void consume_prefetch_responses(void);
-static uint64 prefetch_register_buffer(BufferTag tag, XLogRecPtr *force_request_lsn, XLogRecPtr *force_not_modified_since);
+static uint64 prefetch_register_buffer(BufferTag tag, bool *force_latest, XLogRecPtr *force_lsn);
 static bool prefetch_read(PrefetchRequest *slot);
-static void prefetch_do_request(PrefetchRequest *slot, XLogRecPtr *force_request_lsn, XLogRecPtr *force_not_modified_since);
+static void prefetch_do_request(PrefetchRequest *slot, bool *force_latest, XLogRecPtr *force_lsn);
 static bool prefetch_wait_for(uint64 ring_index);
 static void prefetch_cleanup_trailing_unused(void);
 static inline void prefetch_set_unused(uint64 ring_index);

-static void neon_get_request_lsn(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
-								 XLogRecPtr *request_lsn, XLogRecPtr *not_modified_since);
-static bool neon_prefetch_response_usable(XLogRecPtr request_lsn, XLogRecPtr not_modified_since,
-										  PrefetchRequest *slot);
+static XLogRecPtr neon_get_request_lsn(bool *latest, NRelFileInfo rinfo,
+									   ForkNumber forknum, BlockNumber blkno);

 static bool
 compact_prefetch_buffers(void)
@@ -338,8 +338,8 @@ compact_prefetch_buffers(void)
 		target_slot->shard_no = source_slot->shard_no;
 		target_slot->status = source_slot->status;
 		target_slot->response = source_slot->response;
-		target_slot->request_lsn = source_slot->request_lsn;
-		target_slot->not_modified_since = source_slot->not_modified_since;
+		target_slot->effective_request_lsn = source_slot->effective_request_lsn;
+		target_slot->actual_request_lsn = source_slot->actual_request_lsn;
 		target_slot->my_ring_index = empty_ring_index;

 		prfh_delete(MyPState->prf_hash, source_slot);
@@ -358,8 +358,7 @@ compact_prefetch_buffers(void)
 		};
 		source_slot->response = NULL;
 		source_slot->my_ring_index = 0;
-		source_slot->request_lsn = InvalidXLogRecPtr;
-		source_slot->not_modified_since = InvalidXLogRecPtr;
+		source_slot->effective_request_lsn = 0;

 		/* update bookkeeping */
 		n_moved++;
@@ -684,39 +683,56 @@ prefetch_set_unused(uint64 ring_index)
 		compact_prefetch_buffers();
 }

-/*
- * Send one prefetch request to the pageserver. To wait for the response, call
- * prefetch_wait_for().
- */
 static void
-prefetch_do_request(PrefetchRequest *slot, XLogRecPtr *force_request_lsn, XLogRecPtr *force_not_modified_since)
+prefetch_do_request(PrefetchRequest *slot, bool *force_latest, XLogRecPtr *force_lsn)
 {
 	bool		found;
 	NeonGetPageRequest request = {
 		.req.tag = T_NeonGetPageRequest,
-		/* lsn and not_modified_since are filled in below */
+		.req.latest = false,
+		.req.lsn = 0,
 		.rinfo = BufTagGetNRelFileInfo(slot->buftag),
 		.forknum = slot->buftag.forkNum,
 		.blkno = slot->buftag.blockNum,
 	};

-	Assert(((force_request_lsn != NULL) == (force_not_modified_since != NULL)));
-
-	if (force_request_lsn)
+	if (force_lsn && force_latest)
 	{
-		request.req.lsn = *force_request_lsn;
-		request.req.not_modified_since = *force_not_modified_since;
+		request.req.lsn = *force_lsn;
+		request.req.latest = *force_latest;
+		slot->actual_request_lsn = slot->effective_request_lsn = *force_lsn;
 	}
 	else
 	{
-		neon_get_request_lsn(BufTagGetNRelFileInfo(slot->buftag),
-							 slot->buftag.forkNum,
-							 slot->buftag.blockNum,
-							 &request.req.lsn,
-							 &request.req.not_modified_since);
+		XLogRecPtr	lsn = neon_get_request_lsn(
+											   &request.req.latest,
+											   BufTagGetNRelFileInfo(slot->buftag),
+											   slot->buftag.forkNum,
+											   slot->buftag.blockNum
+			);
+
+		/*
+		 * Note: effective_request_lsn is potentially higher than the
+		 * requested LSN, but still correct:
+		 *
+		 * We know there are no changes between the actual requested LSN and
+		 * the value of effective_request_lsn: If there were, the page would
+		 * have been in cache and evicted between those LSN values, which then
+		 * would have had to result in a larger request LSN for this page.
+		 *
+		 * It is possible that a concurrent backend loads the page, modifies
+		 * it and then evicts it again, but the LSN of that eviction cannot be
+		 * smaller than the current WAL insert/redo pointer, which is already
+		 * larger than this prefetch_lsn. So in any case, that would
+		 * invalidate this cache.
+		 *
+		 * The best LSN to use for effective_request_lsn would be
+		 * XLogCtl->Insert.RedoRecPtr, but that's expensive to access.
+		 */
+		slot->actual_request_lsn = request.req.lsn = lsn;
+		prefetch_lsn = Max(prefetch_lsn, lsn);
+		slot->effective_request_lsn = prefetch_lsn;
 	}
-	slot->request_lsn = request.req.lsn;
-	slot->not_modified_since = request.req.not_modified_since;

 	Assert(slot->response == NULL);
 	Assert(slot->my_ring_index == MyPState->ring_unused);
@@ -733,6 +749,7 @@ prefetch_do_request(PrefetchRequest *slot, XLogRecPtr *force_request_lsn, XLogRe
 	/* update slot state */
 	slot->status = PRFS_REQUESTED;

+
 	prfh_insert(MyPState->prf_hash, slot, &found);
 	Assert(!found);
 }
@@ -742,25 +759,22 @@ prefetch_do_request(PrefetchRequest *slot, XLogRecPtr *force_request_lsn, XLogRe
 *
 * Register that we may want the contents of BufferTag in the near future.
 *
- * If force_request_lsn and force_not_modified_since are not NULL, those
- * values are sent to the pageserver. If they are NULL, we utilize the
- * lastWrittenLsn -infrastructure to fill them in.
+ * If force_latest and force_lsn are not NULL, those values are sent to the
+ * pageserver. If they are NULL, we utilize the lastWrittenLsn -infrastructure
+ * to fill in these values manually.
 *
 * NOTE: this function may indirectly update MyPState->pfs_hash; which
 * invalidates any active pointers into the hash table.
 */

 static uint64
-prefetch_register_buffer(BufferTag tag, XLogRecPtr *force_request_lsn,
-						 XLogRecPtr *force_not_modified_since)
+prefetch_register_buffer(BufferTag tag, bool *force_latest, XLogRecPtr *force_lsn)
 {
 	uint64		ring_index;
 	PrefetchRequest req;
 	PrefetchRequest *slot;
 	PrfHashEntry *entry;

-	Assert(((force_request_lsn != NULL) == (force_not_modified_since != NULL)));
-
 	/* use an intermediate PrefetchRequest struct to ensure correct alignment */
 	req.buftag = tag;
 Retry:
@@ -778,19 +792,40 @@ Retry:
 		Assert(BUFFERTAGS_EQUAL(slot->buftag, tag));

 		/*
-		 * If the caller specified a request LSN to use, only accept prefetch
-		 * responses that satisfy that request.
+		 * If we want a specific lsn, we do not accept requests that were made
+		 * with a potentially different LSN.
 		 */
-		if (force_request_lsn)
+		if (force_latest && force_lsn)
 		{
-			if (!neon_prefetch_response_usable(*force_request_lsn,
-											   *force_not_modified_since, slot))
+			/*
+			 * if we want the latest version, any effective_request_lsn <
+			 * request lsn is OK
+			 */
+			if (*force_latest)
 			{
-				/* Wait for the old request to finish and discard it */
-				if (!prefetch_wait_for(ring_index))
-					goto Retry;
-				prefetch_set_unused(ring_index);
-				entry = NULL;
+				if (*force_lsn > slot->effective_request_lsn)
+				{
+					if (!prefetch_wait_for(ring_index))
+						goto Retry;
+					prefetch_set_unused(ring_index);
+					entry = NULL;
+				}
+
+			}
+
+			/*
+			 * if we don't want the latest version, only accept requests with
+			 * the exact same LSN
+			 */
+			else
+			{
+				if (*force_lsn != slot->effective_request_lsn)
+				{
+					if (!prefetch_wait_for(ring_index))
+						goto Retry;
+					prefetch_set_unused(ring_index);
+					entry = NULL;
+				}
 			}
 		}

@@ -886,7 +921,7 @@ Retry:
 	slot->shard_no = get_shard_number(&tag);
 	slot->my_ring_index = ring_index;

-	prefetch_do_request(slot, force_request_lsn, force_not_modified_since);
+	prefetch_do_request(slot, force_latest, force_lsn);
 	Assert(slot->status == PRFS_REQUESTED);
 	Assert(MyPState->ring_last <= ring_index &&
 		   ring_index < MyPState->ring_unused);
@@ -915,7 +950,7 @@ page_server_request(void const *req)
 	BufferTag tag = {0};
 	shardno_t shard_no;

-	switch (messageTag(req))
+	switch (((NeonRequest *) req)->tag)
 	{
 		case T_NeonExistsRequest:
 			CopyNRelFileInfoToBufTag(tag, ((NeonExistsRequest *) req)->rinfo);
@@ -931,10 +966,11 @@ page_server_request(void const *req)
 			tag.blockNum = ((NeonGetPageRequest *) req)->blkno;
 			break;
 		default:
-			neon_log(ERROR, "Unexpected request tag: %d", messageTag(req));
+			neon_log(ERROR, "Unexpected request tag: %d", ((NeonRequest *) req)->tag);
 	}
 	shard_no = get_shard_number(&tag);

+
 	/*
 	 * Current sharding model assumes that all metadata is present only at shard 0.
 	 * We still need to call get_shard_no() to check if shard map is up-to-date.
@@ -961,52 +997,8 @@ nm_pack_request(NeonRequest *msg)
 	StringInfoData s;

 	initStringInfo(&s);
+	pq_sendbyte(&s, msg->tag);

-	if (neon_protocol_version >= 2)
-	{
-		pq_sendbyte(&s, msg->tag);
-		pq_sendint64(&s, msg->lsn);
-		pq_sendint64(&s, msg->not_modified_since);
-	}
-	else
-	{
-		bool		latest;
-		XLogRecPtr	lsn;
-
-		/*
-		 * In primary, we always request the latest page version.
-		 */
-		if (!RecoveryInProgress())
-		{
-			latest = true;
-			lsn = msg->not_modified_since;
-		}
-		else
-		{
-			/*
-			 * In the protocol V1, we cannot represent that we want to read
-			 * page at LSN X, and we know that it hasn't been modified since
-			 * Y. We can either use 'not_modified_lsn' as the request LSN, and
-			 * risk getting an error if that LSN is too old and has already
-			 * fallen out of the pageserver's GC horizon, or we can send
-			 * 'request_lsn', causing the pageserver to possibly wait for the
-			 * recent WAL to arrive unnecessarily. Or something in between. We
-			 * choose to use the old LSN and risk GC errors, because that's
-			 * what we've done historically.
-			 */
-			latest = false;
-			lsn = msg->not_modified_since;
-		}
-
-		pq_sendbyte(&s, msg->tag);
-		pq_sendbyte(&s, latest);
-		pq_sendint64(&s, lsn);
-	}
-
-	/*
-	 * The rest of the request messages are the same between protocol V1 and
-	 * V2
-	 */
 	switch (messageTag(msg))
 	{
 			/* pagestore_client -> pagestore */
@@ -1014,6 +1006,8 @@ nm_pack_request(NeonRequest *msg)
 			{
 				NeonExistsRequest *msg_req = (NeonExistsRequest *) msg;

+				pq_sendbyte(&s, msg_req->req.latest);
+				pq_sendint64(&s, msg_req->req.lsn);
 				pq_sendint32(&s, NInfoGetSpcOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetDbOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetRelNumber(msg_req->rinfo));
@@ -1025,6 +1019,8 @@ nm_pack_request(NeonRequest *msg)
 			{
 				NeonNblocksRequest *msg_req = (NeonNblocksRequest *) msg;

+				pq_sendbyte(&s, msg_req->req.latest);
+				pq_sendint64(&s, msg_req->req.lsn);
 				pq_sendint32(&s, NInfoGetSpcOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetDbOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetRelNumber(msg_req->rinfo));
@@ -1036,6 +1032,8 @@ nm_pack_request(NeonRequest *msg)
 			{
 				NeonDbSizeRequest *msg_req = (NeonDbSizeRequest *) msg;

+				pq_sendbyte(&s, msg_req->req.latest);
+				pq_sendint64(&s, msg_req->req.lsn);
 				pq_sendint32(&s, msg_req->dbNode);

 				break;
@@ -1044,6 +1042,8 @@ nm_pack_request(NeonRequest *msg)
 			{
 				NeonGetPageRequest *msg_req = (NeonGetPageRequest *) msg;

+				pq_sendbyte(&s, msg_req->req.latest);
+				pq_sendint64(&s, msg_req->req.lsn);
 				pq_sendint32(&s, NInfoGetSpcOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetDbOid(msg_req->rinfo));
 				pq_sendint32(&s, NInfoGetRelNumber(msg_req->rinfo));
@@ -1057,6 +1057,8 @@ nm_pack_request(NeonRequest *msg)
 			{
 				NeonGetSlruSegmentRequest *msg_req = (NeonGetSlruSegmentRequest *) msg;

+				pq_sendbyte(&s, msg_req->req.latest);
+				pq_sendint64(&s, msg_req->req.lsn);
 				pq_sendbyte(&s, msg_req->kind);
 				pq_sendint32(&s, msg_req->segno);

@@ -1207,7 +1209,7 @@ nm_to_string(NeonMessage *msg)
 				appendStringInfo(&s, ", \"rinfo\": \"%u/%u/%u\"", RelFileInfoFmt(msg_req->rinfo));
 				appendStringInfo(&s, ", \"forknum\": %d", msg_req->forknum);
 				appendStringInfo(&s, ", \"lsn\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.lsn));
-				appendStringInfo(&s, ", \"not_modified_since\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.not_modified_since));
+				appendStringInfo(&s, ", \"latest\": %d", msg_req->req.latest);
 				appendStringInfoChar(&s, '}');
 				break;
 			}
@@ -1220,7 +1222,7 @@ nm_to_string(NeonMessage *msg)
 				appendStringInfo(&s, ", \"rinfo\": \"%u/%u/%u\"", RelFileInfoFmt(msg_req->rinfo));
 				appendStringInfo(&s, ", \"forknum\": %d", msg_req->forknum);
 				appendStringInfo(&s, ", \"lsn\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.lsn));
-				appendStringInfo(&s, ", \"not_modified_since\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.not_modified_since));
+				appendStringInfo(&s, ", \"latest\": %d", msg_req->req.latest);
 				appendStringInfoChar(&s, '}');
 				break;
 			}
@@ -1234,7 +1236,7 @@ nm_to_string(NeonMessage *msg)
 				appendStringInfo(&s, ", \"forknum\": %d", msg_req->forknum);
 				appendStringInfo(&s, ", \"blkno\": %u", msg_req->blkno);
 				appendStringInfo(&s, ", \"lsn\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.lsn));
-				appendStringInfo(&s, ", \"not_modified_since\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.not_modified_since));
+				appendStringInfo(&s, ", \"latest\": %d", msg_req->req.latest);
 				appendStringInfoChar(&s, '}');
 				break;
 			}
@@ -1245,7 +1247,7 @@ nm_to_string(NeonMessage *msg)
 				appendStringInfoString(&s, "{\"type\": \"NeonDbSizeRequest\"");
 				appendStringInfo(&s, ", \"dbnode\": \"%u\"", msg_req->dbNode);
 				appendStringInfo(&s, ", \"lsn\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.lsn));
-				appendStringInfo(&s, ", \"not_modified_since\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.not_modified_since));
+				appendStringInfo(&s, ", \"latest\": %d", msg_req->req.latest);
 				appendStringInfoChar(&s, '}');
 				break;
 			}
@@ -1257,7 +1259,7 @@ nm_to_string(NeonMessage *msg)
 				appendStringInfo(&s, ", \"kind\": %u", msg_req->kind);
 				appendStringInfo(&s, ", \"segno\": %u", msg_req->segno);
 				appendStringInfo(&s, ", \"lsn\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.lsn));
-				appendStringInfo(&s, ", \"not_modified_since\": \"%X/%X\"", LSN_FORMAT_ARGS(msg_req->req.not_modified_since));
+				appendStringInfo(&s, ", \"latest\": %d", msg_req->req.latest);
 				appendStringInfoChar(&s, '}');
 				break;
 			}
@@ -1529,38 +1531,44 @@ nm_adjust_lsn(XLogRecPtr lsn)
 /*
 * Return LSN for requesting pages and number of blocks from page server
 */
-static void
-neon_get_request_lsn(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
-					 XLogRecPtr *request_lsn, XLogRecPtr *not_modified_since)
+static XLogRecPtr
+neon_get_request_lsn(bool *latest, NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno)
 {
-	XLogRecPtr	last_written_lsn;
-
-	last_written_lsn = GetLastWrittenLSN(rinfo, forknum, blkno);
-	last_written_lsn = nm_adjust_lsn(last_written_lsn);
-	Assert(last_written_lsn != InvalidXLogRecPtr);
+	XLogRecPtr	lsn;

 	if (RecoveryInProgress())
 	{
-		/* Request the page at the last replayed LSN. */
-		*request_lsn = GetXLogReplayRecPtr(NULL);
-		*not_modified_since = last_written_lsn;
-		Assert(last_written_lsn <= *request_lsn);
+		/*
+		 * We don't know if WAL has been generated but not yet replayed, so
+		 * we're conservative in our estimates about latest pages.
+		 */
+		*latest = false;

-		neon_log(DEBUG1, "neon_get_request_lsn request lsn %X/%X, not_modified_since %X/%X",
-				 LSN_FORMAT_ARGS(*request_lsn), LSN_FORMAT_ARGS(*not_modified_since));
+		/*
+		 * Get the last written LSN of this page.
+		 */
+		lsn = GetLastWrittenLSN(rinfo, forknum, blkno);
+		lsn = nm_adjust_lsn(lsn);
+
+		neon_log(DEBUG1, "neon_get_request_lsn GetXLogReplayRecPtr %X/%X request lsn 0 ",
+			 (uint32) ((lsn) >> 32), (uint32) (lsn));
 	}
 	else
 	{
 		XLogRecPtr	flushlsn;

 		/*
-		 * Use the latest LSN that was evicted from the buffer cache as the
-		 * 'not_modified_since' hint. Any pages modified by later WAL records
-		 * must still in the buffer cache, so our request cannot concern
-		 * those.
+		 * Use the latest LSN that was evicted from the buffer cache. Any
+		 * pages modified by later WAL records must still in the buffer cache,
+		 * so our request cannot concern those.
 		 */
+		*latest = true;
+		lsn = GetLastWrittenLSN(rinfo, forknum, blkno);
+		Assert(lsn != InvalidXLogRecPtr);
 		neon_log(DEBUG1, "neon_get_request_lsn GetLastWrittenLSN lsn %X/%X ",
-				 LSN_FORMAT_ARGS(last_written_lsn));
+			 (uint32) ((lsn) >> 32), (uint32) (lsn));
+
+		lsn = nm_adjust_lsn(lsn);

 		/*
 		 * Is it possible that the last-written LSN is ahead of last flush
@@ -1575,109 +1583,16 @@ neon_get_request_lsn(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 #else
 		flushlsn = GetFlushRecPtr();
 #endif
-		if (last_written_lsn > flushlsn)
+		if (lsn > flushlsn)
 		{
 			neon_log(DEBUG5, "last-written LSN %X/%X is ahead of last flushed LSN %X/%X",
-					 LSN_FORMAT_ARGS(last_written_lsn),
-					 LSN_FORMAT_ARGS(flushlsn));
-			XLogFlush(last_written_lsn);
-			flushlsn = last_written_lsn;
+				 (uint32) (lsn >> 32), (uint32) lsn,
+				 (uint32) (flushlsn >> 32), (uint32) flushlsn);
+			XLogFlush(lsn);
 		}
-
-		/*
-		 * Request the latest version of the page. The most up-to-date request
-		 * LSN we could use would be the current insert LSN, but to avoid the
-		 * overhead of looking it up, use 'flushlsn' instead. This relies on
-		 * the assumption that if the page was modified since the last WAL
-		 * flush, it should still be in the buffer cache, and we wouldn't be
-		 * requesting it.
-		 */
-		*request_lsn = flushlsn;
-		*not_modified_since = last_written_lsn;
-	}
-}
-
-/*
- *  neon_prefetch_response_usable -- Can a new request be satisfied by old one?
- *
- * This is used to check if the response to a prefetch request can be used to
- * satisfy a page read now.
- */
-static bool
-neon_prefetch_response_usable(XLogRecPtr request_lsn, XLogRecPtr not_modified_since,
-							  PrefetchRequest *slot)
-{
-	/* sanity check the LSN's on the old and the new request */
-	Assert(request_lsn >= not_modified_since);
-	Assert(slot->request_lsn >= slot->not_modified_since);
-	Assert(slot->status != PRFS_UNUSED);
-
-	/*
-	 * The new request's LSN should never be older than the old one.  This
-	 * could be an Assert, except that for testing purposes, we do provide an
-	 * interface in neon_test_utils to fetch pages at arbitary LSNs, which
-	 * violates this.
-	 *
-	 * Similarly, the not_modified_since value calculated for a page should
-	 * never move backwards. This assumption is a bit fragile; if we updated
-	 * the last-written cache when we read in a page, for example, then it
-	 * might. But as the code stands, it should not.
-	 *
-	 * (If two backends issue a request at the same time, they might race and
-	 * calculate LSNs "out of order" with each other, but the prefetch queue
-	 * is backend-private at the moment.)
-	 */
-	if (request_lsn < slot->request_lsn || not_modified_since < slot->not_modified_since)
-	{
-		ereport(LOG,
-				(errcode(ERRCODE_IO_ERROR),
-				 errmsg(NEON_TAG "request with unexpected LSN after prefetch"),
-				 errdetail("Request %X/%X not_modified_since %X/%X, prefetch %X/%X not_modified_since %X/%X)",
-						   LSN_FORMAT_ARGS(request_lsn), LSN_FORMAT_ARGS(not_modified_since),
-						   LSN_FORMAT_ARGS(slot->request_lsn), LSN_FORMAT_ARGS(slot->not_modified_since))));
-		return false;
 	}

-	/*---
-	 * Each request to the pageserver carries two LSN values:
-	 * `not_modified_since` and `request_lsn`. The (not_modified_since,
-	 * request_lsn] range of each request is effectively a claim that the page
-	 * has not been modified between those LSNs.  If the range of the old
-	 * request in the queue overlaps with the new request, we know that the
-	 * page hasn't been modified in the union of the ranges. We can use the
-	 * response to old request to satisfy the new request in that case. For
-	 * example:
-	 *
-	 *              100      500
-	 * Old request:  +--------+
-	 *
-	 *                     400      800
-	 * New request:         +--------+
-	 *
-	 * The old request claims that the page was not modified between LSNs 100
-	 * and 500, and the second claims that it was not modified between 400 and
-	 * 800. Together they mean that the page was not modified between 100 and
-	 * 800. Therefore the response to the old request is also valid for the
-	 * new request.
-	 *
-	 * This logic also holds at the boundary case that the old request's LSN
-	 * matches the new request's not_modified_since LSN exactly:
-	 *
-	 *              100      500
-	 * Old request:  +--------+
-	 *
-	 *                       500      900
-	 * New request:           +--------+
-	 *
-	 * The response to the old request is the page as it was at LSN 500, and
-	 * the page hasn't been changed in the range (500, 900], therefore the
-	 * response is valid also for the new request.
-	 */
-
-	/* this follows from the checks above */
-	Assert(request_lsn >= slot->not_modified_since);
-
-	return not_modified_since <= slot->request_lsn;
+	return lsn;
 }

 /*
@@ -1689,8 +1604,8 @@ neon_exists(SMgrRelation reln, ForkNumber forkNum)
 	bool		exists;
 	NeonResponse *resp;
 	BlockNumber n_blocks;
+	bool		latest;
 	XLogRecPtr	request_lsn;
-	XLogRecPtr	not_modified_since;

 	switch (reln->smgr_relpersistence)
 	{
@@ -1745,13 +1660,12 @@ neon_exists(SMgrRelation reln, ForkNumber forkNum)
 		return false;
 	}

-	neon_get_request_lsn(InfoFromSMgrRel(reln), forkNum, REL_METADATA_PSEUDO_BLOCKNO,
-						 &request_lsn, &not_modified_since);
+	request_lsn = neon_get_request_lsn(&latest, InfoFromSMgrRel(reln), forkNum, REL_METADATA_PSEUDO_BLOCKNO);
 	{
 		NeonExistsRequest request = {
 			.req.tag = T_NeonExistsRequest,
+			.req.latest = latest,
 			.req.lsn = request_lsn,
-			.req.not_modified_since = not_modified_since,
 			.rinfo = InfoFromSMgrRel(reln),
 		.forknum = forkNum};

@@ -2188,10 +2102,10 @@ neon_writeback(SMgrRelation reln, ForkNumber forknum,
 void
 #if PG_MAJORVERSION_NUM < 16
 neon_read_at_lsn(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
-				 XLogRecPtr request_lsn, XLogRecPtr not_modified_since, char *buffer)
+				 XLogRecPtr request_lsn, bool request_latest, char *buffer)
 #else
 neon_read_at_lsn(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
-				 XLogRecPtr request_lsn, XLogRecPtr not_modified_since, void *buffer)
+				 XLogRecPtr request_lsn, bool request_latest, void *buffer)
 #endif
 {
 	NeonResponse *resp;
@@ -2234,16 +2148,15 @@ neon_read_at_lsn(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 	if (entry != NULL)
 	{
 		slot = entry->slot;
-		if (neon_prefetch_response_usable(request_lsn, not_modified_since, slot))
+		if (slot->effective_request_lsn >= request_lsn)
 		{
 			ring_index = slot->my_ring_index;
 			pgBufferUsage.prefetch.hits += 1;
 		}
-		else
+		else					/* the current prefetch LSN is not large
+								 * enough, so drop the prefetch */
 		{
 			/*
-			 * Cannot use this prefetch, discard it
-			 *
 			 * We can't drop cache for not-yet-received requested items. It is
 			 * unlikely this happens, but it can happen if prefetch distance
 			 * is large enough and a backend didn't consume all prefetch
@@ -2268,8 +2181,8 @@ neon_read_at_lsn(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 		{
 			pgBufferUsage.prefetch.misses += 1;

-			ring_index = prefetch_register_buffer(buftag, &request_lsn,
-												  &not_modified_since);
+			ring_index = prefetch_register_buffer(buftag, &request_latest,
+												  &request_lsn);
 			slot = GetPrfSlot(ring_index);
 		}
 		else
@@ -2333,8 +2246,8 @@ neon_read(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno, char *buffer
 neon_read(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno, void *buffer)
 #endif
 {
+	bool		latest;
 	XLogRecPtr	request_lsn;
-	XLogRecPtr	not_modified_since;

 	switch (reln->smgr_relpersistence)
 	{
@@ -2359,9 +2272,8 @@ neon_read(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno, void *buffer
 		return;
 	}

-	neon_get_request_lsn(InfoFromSMgrRel(reln), forkNum, blkno,
-						 &request_lsn, &not_modified_since);
-	neon_read_at_lsn(InfoFromSMgrRel(reln), forkNum, blkno, request_lsn, not_modified_since, buffer);
+	request_lsn = neon_get_request_lsn(&latest, InfoFromSMgrRel(reln), forkNum, blkno);
+	neon_read_at_lsn(InfoFromSMgrRel(reln), forkNum, blkno, request_lsn, latest, buffer);

 #ifdef DEBUG_COMPARE_LOCAL
 	if (forkNum == MAIN_FORKNUM && IS_LOCAL_REL(reln))
@@ -2530,8 +2442,8 @@ neon_nblocks(SMgrRelation reln, ForkNumber forknum)
 {
 	NeonResponse *resp;
 	BlockNumber n_blocks;
+	bool		latest;
 	XLogRecPtr	request_lsn;
-	XLogRecPtr	not_modified_since;

 	switch (reln->smgr_relpersistence)
 	{
@@ -2558,13 +2470,12 @@ neon_nblocks(SMgrRelation reln, ForkNumber forknum)
 		return n_blocks;
 	}

-	neon_get_request_lsn(InfoFromSMgrRel(reln), forknum, REL_METADATA_PSEUDO_BLOCKNO,
-						 &request_lsn, &not_modified_since);
+	request_lsn = neon_get_request_lsn(&latest, InfoFromSMgrRel(reln), forknum, REL_METADATA_PSEUDO_BLOCKNO);
 	{
 		NeonNblocksRequest request = {
 			.req.tag = T_NeonNblocksRequest,
+			.req.latest = latest,
 			.req.lsn = request_lsn,
-			.req.not_modified_since = not_modified_since,
 			.rinfo = InfoFromSMgrRel(reln),
 			.forknum = forknum,
 		};
@@ -2612,17 +2523,16 @@ neon_dbsize(Oid dbNode)
 {
 	NeonResponse *resp;
 	int64		db_size;
-	XLogRecPtr	request_lsn,
-				not_modified_since;
+	XLogRecPtr	request_lsn;
+	bool		latest;
 	NRelFileInfo dummy_node = {0};

-	neon_get_request_lsn(dummy_node, MAIN_FORKNUM, REL_METADATA_PSEUDO_BLOCKNO,
-						 &request_lsn, &not_modified_since);
+	request_lsn = neon_get_request_lsn(&latest, dummy_node, MAIN_FORKNUM, REL_METADATA_PSEUDO_BLOCKNO);
 	{
 		NeonDbSizeRequest request = {
 			.req.tag = T_NeonDbSizeRequest,
+			.req.latest = latest,
 			.req.lsn = request_lsn,
-			.req.not_modified_since = not_modified_since,
 			.dbNode = dbNode,
 		};

@@ -2695,6 +2605,7 @@ neon_truncate(SMgrRelation reln, ForkNumber forknum, BlockNumber nblocks)
 	 * the most recently inserted WAL record's LSN.
 	 */
 	lsn = GetXLogInsertRecPtr();
+
 	lsn = nm_adjust_lsn(lsn);

 	/*
@@ -2894,33 +2805,14 @@ neon_end_unlogged_build(SMgrRelation reln)
 static int
 neon_read_slru_segment(SMgrRelation reln, const char* path, int segno, void* buffer)
 {
-	XLogRecPtr request_lsn,
-		not_modified_since;
-
-	if (RecoveryInProgress())
-	{
-		request_lsn = GetXLogReplayRecPtr(NULL);
-		if (request_lsn == InvalidXLogRecPtr)
-		{
-			/*
-			 * This happens in neon startup, we start up without replaying any
-			 * records.
-			 */
-			request_lsn = GetRedoStartLsn();
-		}
-	}
-	else
-		request_lsn = GetXLogInsertRecPtr();
-	request_lsn = nm_adjust_lsn(request_lsn);
-
+	XLogRecPtr request_lsn;
 	/*
-	 * GetRedoStartLsn() returns LSN of basebackup. We know that the SLRU
-	 * segment has not changed since the basebackup, because in order to
-	 * modify it, we would have had to download it already. And once
-	 * downloaded, we never evict SLRU segments from local disk.
+	 * GetRedoStartLsn() returns LSN of basebackup.
+	 * We need to download SLRU segments only once after node startup,
+	 * then SLRUs are maintained locally.
 	 */
-	not_modified_since = GetRedoStartLsn();
-
+	request_lsn = GetRedoStartLsn();
+	request_lsn = nm_adjust_lsn(request_lsn);
 	SlruKind kind;

    if (STRPREFIX(path, "pg_xact"))
@@ -2935,8 +2827,8 @@ neon_read_slru_segment(SMgrRelation reln, const char* path, int segno, void* buf
 	NeonResponse *resp;
 	NeonGetSlruSegmentRequest request = {
 		.req.tag = T_NeonGetSlruSegmentRequest,
+		.req.latest = false,
 		.req.lsn = request_lsn,
-		.req.not_modified_since = not_modified_since,

 		.kind = kind,
 		.segno = segno
@@ -3064,9 +2956,6 @@ neon_extend_rel_size(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 {
 	BlockNumber relsize;

-	/* This is only used in WAL replay */
-	Assert(RecoveryInProgress());
-
 	/* Extend the relation if we know its size */
 	if (get_cached_relsize(rinfo, forknum, &relsize))
 	{
@@ -3085,13 +2974,14 @@ neon_extend_rel_size(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 		 * This length is later reused when we open the smgr to read the
 		 * block, which is fine and expected.
 		 */
+
 		NeonResponse *response;
 		NeonNblocksResponse *nbresponse;
 		NeonNblocksRequest request = {
 			.req = (NeonRequest) {
-				.tag = T_NeonNblocksRequest,
 				.lsn = end_recptr,
-				.not_modified_since = end_recptr,
+				.latest = false,
+				.tag = T_NeonNblocksRequest,
 			},
 			.rinfo = rinfo,
 			.forknum = forknum,
--- a/pgxn/neon_test_utils/Makefile
+++ b/pgxn/neon_test_utils/Makefile
@@ -7,7 +7,7 @@ OBJS = \
 	neontest.o

 EXTENSION = neon_test_utils
-DATA = neon_test_utils--1.1.sql
+DATA = neon_test_utils--1.0.sql
 PGFILEDESC = "neon_test_utils - helpers for neon testing and debugging"

 PG_CONFIG = pg_config
--- a/pgxn/neon_test_utils/neon_test_utils--1.0.sql
+++ b/pgxn/neon_test_utils/neon_test_utils--1.0.sql
@@ -31,12 +31,12 @@ AS 'MODULE_PATHNAME', 'clear_buffer_cache'
 LANGUAGE C STRICT
 PARALLEL UNSAFE;

-CREATE FUNCTION get_raw_page_at_lsn(relname text, forkname text, blocknum int8, request_lsn pg_lsn, not_modified_since pg_lsn)
+CREATE FUNCTION get_raw_page_at_lsn(relname text, forkname text, blocknum int8, lsn pg_lsn)
 RETURNS bytea
 AS 'MODULE_PATHNAME', 'get_raw_page_at_lsn'
 LANGUAGE C PARALLEL UNSAFE;

-CREATE FUNCTION get_raw_page_at_lsn(tbspc oid, db oid, relfilenode oid, forknum int8, blocknum int8, request_lsn pg_lsn, not_modified_since pg_lsn)
+CREATE FUNCTION get_raw_page_at_lsn(tbspc oid, db oid, relfilenode oid, forknum int8, blocknum int8, lsn pg_lsn)
 RETURNS bytea
 AS 'MODULE_PATHNAME', 'get_raw_page_at_lsn_ex'
 LANGUAGE C PARALLEL UNSAFE;
--- a/pgxn/neon_test_utils/neon_test_utils.control
+++ b/pgxn/neon_test_utils/neon_test_utils.control
@@ -1,6 +1,6 @@
 # neon_test_utils extension
 comment = 'helpers for neon testing and debugging'
-default_version = '1.1'
+default_version = '1.0'
 module_pathname = '$libdir/neon_test_utils'
 relocatable = true
 trusted = true
--- a/pgxn/neon_test_utils/neontest.c
+++ b/pgxn/neon_test_utils/neontest.c
@@ -48,10 +48,10 @@ PG_FUNCTION_INFO_V1(neon_xlogflush);
 */
 #if PG_MAJORVERSION_NUM < 16
 typedef void (*neon_read_at_lsn_type) (NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
-									   XLogRecPtr request_lsn, XLogRecPtr not_modified_since, char *buffer);
+									   XLogRecPtr request_lsn, bool request_latest, char *buffer);
 #else
 typedef void (*neon_read_at_lsn_type) (NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
-									   XLogRecPtr request_lsn, XLogRecPtr not_modified_since, void *buffer);
+									   XLogRecPtr request_lsn, bool request_latest, void *buffer);
 #endif

 static neon_read_at_lsn_type neon_read_at_lsn_ptr;
@@ -299,11 +299,8 @@ get_raw_page_at_lsn(PG_FUNCTION_ARGS)
 	text	   *forkname;
 	uint32		blkno;

-	XLogRecPtr	request_lsn;
-	XLogRecPtr	not_modified_since;
-
-	if (PG_NARGS() != 5)
-		elog(ERROR, "unexpected number of arguments in SQL function signature");
+	bool		request_latest = PG_ARGISNULL(3);
+	uint64		read_lsn = request_latest ? GetXLogInsertRecPtr() : PG_GETARG_INT64(3);

 	if (PG_ARGISNULL(0) || PG_ARGISNULL(1) || PG_ARGISNULL(2))
 		PG_RETURN_NULL();
@@ -312,9 +309,6 @@ get_raw_page_at_lsn(PG_FUNCTION_ARGS)
 	forkname = PG_GETARG_TEXT_PP(1);
 	blkno = PG_GETARG_UINT32(2);

-	request_lsn = PG_ARGISNULL(3) ? GetXLogInsertRecPtr() : PG_GETARG_LSN(3);
-	not_modified_since = PG_ARGISNULL(4) ? request_lsn : PG_GETARG_LSN(4);
-
 	if (!superuser())
 		ereport(ERROR,
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
@@ -367,7 +361,7 @@ get_raw_page_at_lsn(PG_FUNCTION_ARGS)
 	SET_VARSIZE(raw_page, BLCKSZ + VARHDRSZ);
 	raw_page_data = VARDATA(raw_page);

-	neon_read_at_lsn(InfoFromRelation(rel), forknum, blkno, request_lsn, not_modified_since, raw_page_data);
+	neon_read_at_lsn(InfoFromRelation(rel), forknum, blkno, read_lsn, request_latest, raw_page_data);

 	relation_close(rel, AccessShareLock);

@@ -386,9 +380,6 @@ get_raw_page_at_lsn_ex(PG_FUNCTION_ARGS)
 {
 	char	   *raw_page_data;

-	if (PG_NARGS() != 7)
-		elog(ERROR, "unexpected number of arguments in SQL function signature");
-
 	if (!superuser())
 		ereport(ERROR,
 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
@@ -412,20 +403,18 @@ get_raw_page_at_lsn_ex(PG_FUNCTION_ARGS)
 		};

 		ForkNumber	forknum = PG_GETARG_UINT32(3);
+
 		uint32		blkno = PG_GETARG_UINT32(4);
-		XLogRecPtr	request_lsn;
-		XLogRecPtr	not_modified_since;
+		bool		request_latest = PG_ARGISNULL(5);
+		uint64		read_lsn = request_latest ? GetXLogInsertRecPtr() : PG_GETARG_INT64(5);

 		/* Initialize buffer to copy to */
 		bytea	   *raw_page = (bytea *) palloc(BLCKSZ + VARHDRSZ);

-		request_lsn = PG_ARGISNULL(5) ? GetXLogInsertRecPtr() : PG_GETARG_LSN(5);
-		not_modified_since = PG_ARGISNULL(6) ? request_lsn : PG_GETARG_LSN(6);
-
 		SET_VARSIZE(raw_page, BLCKSZ + VARHDRSZ);
 		raw_page_data = VARDATA(raw_page);

-		neon_read_at_lsn(rinfo, forknum, blkno, request_lsn, not_modified_since, raw_page_data);
+		neon_read_at_lsn(rinfo, forknum, blkno, read_lsn, request_latest, raw_page_data);
 		PG_RETURN_BYTEA_P(raw_page);
 	}
 }
--- a/proxy/Cargo.toml
+++ b/proxy/Cargo.toml
@@ -21,6 +21,7 @@ base64.workspace = true
 bstr.workspace = true
 bytes = { workspace = true, features = ["serde"] }
 camino.workspace = true
+camino-tempfile.workspace = true
 chrono.workspace = true
 clap.workspace = true
 consumption_metrics.workspace = true
@@ -78,7 +79,7 @@ subtle.workspace = true
 sync_wrapper.workspace = true
 task-local-extensions.workspace = true
 thiserror.workspace = true
-tikv-jemallocator.workspace = true
+tikv-jemallocator = { workspace = true, features = ["profiling"] }
 tikv-jemalloc-ctl = { workspace = true, features = ["use_std"] }
 tokio-postgres.workspace = true
 tokio-rustls.workspace = true
@@ -102,7 +103,6 @@ redis.workspace = true
 workspace_hack.workspace = true

 [dev-dependencies]
-camino-tempfile.workspace = true
 fallible-iterator.workspace = true
 rcgen.workspace = true
 rstest.workspace = true
--- a/proxy/src/auth/backend/link.rs
+++ b/proxy/src/auth/backend/link.rs
@@ -79,19 +79,15 @@ pub(super) async fn authenticate(

    // Give user a URL to spawn a new database.
    info!(parent: &span, "sending the auth URL to the user");
-    let pause = ctx.latency_timer.pause(crate::metrics::Waiting::Client);
    client
        .write_message_noflush(&Be::AuthenticationOk)?
        .write_message_noflush(&Be::CLIENT_ENCODING)?
        .write_message(&Be::NoticeResponse(&greeting))
        .await?;
-    drop(pause);

    // Wait for web console response (see `mgmt`).
    info!(parent: &span, "waiting for console's reply...");
-    let pause = ctx.latency_timer.pause(crate::metrics::Waiting::Cplane);
    let db_info = waiter.await.map_err(LinkAuthError::from)?;
-    drop(pause);

    client.write_message_noflush(&Be::NoticeResponse("Connecting to database."))?;

--- a/proxy/src/bin/pg_sni_router.rs
+++ b/proxy/src/bin/pg_sni_router.rs
@@ -279,7 +279,7 @@ async fn handle_client(

    // doesn't yet matter as pg-sni-router doesn't report analytics logs
    ctx.set_success();
-    ctx.log_connect();
+    ctx.log();

    // Starting from here we only proxy the client's traffic.
    info!("performing the proxy pass...");
--- a/proxy/src/bin/proxy.rs
+++ b/proxy/src/bin/proxy.rs
@@ -200,12 +200,6 @@ struct ProxyCliArgs {
    /// Size of each event is no more than 400 bytes, so 2**22 is about 200MB before the compression.
    #[clap(long, default_value = "4194304")]
    metric_backup_collection_chunk_size: usize,
-    /// Whether to retry the connection to the compute node
-    #[clap(long, default_value = config::RetryConfig::CONNECT_TO_COMPUTE_DEFAULT_VALUES)]
-    connect_to_compute_retry: String,
-    /// Whether to retry the wake_compute request
-    #[clap(long, default_value = config::RetryConfig::WAKE_COMPUTE_DEFAULT_VALUES)]
-    wake_compute_retry: String,
 }

 #[derive(clap::Args, Clone, Copy, Debug)]
@@ -403,43 +397,27 @@ async fn main() -> anyhow::Result<()> {
        maintenance_tasks.spawn(usage_metrics::task_main(metrics_config));
        client_tasks.spawn(usage_metrics::task_backup(
            &metrics_config.backup_metric_collection_config,
-            cancellation_token.clone(),
+            cancellation_token,
        ));
    }

    if let auth::BackendType::Console(api, _) = &config.auth_backend {
        if let proxy::console::provider::ConsoleBackend::Console(api) = &**api {
-            match (redis_notifications_client, regional_redis_client.clone()) {
-                (None, None) => {}
-                (client1, client2) => {
-                    let cache = api.caches.project_info.clone();
-                    if let Some(client) = client1 {
-                        maintenance_tasks.spawn(notifications::task_main(
-                            client,
-                            cache.clone(),
-                            cancel_map.clone(),
-                            args.region.clone(),
-                        ));
-                    }
-                    if let Some(client) = client2 {
-                        maintenance_tasks.spawn(notifications::task_main(
-                            client,
-                            cache.clone(),
-                            cancel_map.clone(),
-                            args.region.clone(),
-                        ));
-                    }
-                    maintenance_tasks.spawn(async move { cache.clone().gc_worker().await });
-                }
+            if let Some(redis_notifications_client) = redis_notifications_client {
+                let cache = api.caches.project_info.clone();
+                maintenance_tasks.spawn(notifications::task_main(
+                    redis_notifications_client,
+                    cache.clone(),
+                    cancel_map.clone(),
+                    args.region.clone(),
+                ));
+                maintenance_tasks.spawn(async move { cache.clone().gc_worker().await });
            }
            if let Some(regional_redis_client) = regional_redis_client {
                let cache = api.caches.endpoints_cache.clone();
                let con = regional_redis_client;
                let span = tracing::info_span!("endpoints_cache");
-                maintenance_tasks.spawn(
-                    async move { cache.do_read(con, cancellation_token.clone()).await }
-                        .instrument(span),
-                );
+                maintenance_tasks.spawn(async move { cache.do_read(con).await }.instrument(span));
            }
        }
    }
@@ -606,10 +584,6 @@ fn build_config(args: &ProxyCliArgs) -> anyhow::Result<&'static ProxyConfig> {
        handshake_timeout: args.handshake_timeout,
        region: args.region.clone(),
        aws_region: args.aws_region.clone(),
-        wake_compute_retry_config: config::RetryConfig::parse(&args.wake_compute_retry)?,
-        connect_to_compute_retry_config: config::RetryConfig::parse(
-            &args.connect_to_compute_retry,
-        )?,
    }));

    Ok(config)
--- a/proxy/src/cache/endpoints.rs
+++ b/proxy/src/cache/endpoints.rs
@@ -4,7 +4,6 @@ use std::{
        atomic::{AtomicBool, Ordering},
        Arc,
    },
-    time::Duration,
 };

 use dashmap::DashSet;
@@ -14,7 +13,6 @@ use redis::{
 };
 use serde::Deserialize;
 use tokio::sync::Mutex;
-use tokio_util::sync::CancellationToken;
 use tracing::info;

 use crate::{
@@ -113,22 +111,16 @@ impl EndpointsCache {
    pub async fn do_read(
        &self,
        mut con: ConnectionWithCredentialsProvider,
-        cancellation_token: CancellationToken,
    ) -> anyhow::Result<Infallible> {
        let mut last_id = "0-0".to_string();
        loop {
+            self.ready.store(false, Ordering::Release);
            if let Err(e) = con.connect().await {
                tracing::error!("error connecting to redis: {:?}", e);
-                self.ready.store(false, Ordering::Release);
+                continue;
            }
            if let Err(e) = self.read_from_stream(&mut con, &mut last_id).await {
                tracing::error!("error reading from redis: {:?}", e);
-                self.ready.store(false, Ordering::Release);
-            }
-            if cancellation_token.is_cancelled() {
-                info!("cancellation token is cancelled, exiting");
-                tokio::time::sleep(Duration::from_secs(60 * 60 * 24 * 7)).await;
-                // 1 week.
            }
            tokio::time::sleep(self.config.retry_interval).await;
        }
--- a/proxy/src/compute.rs
+++ b/proxy/src/compute.rs
@@ -260,9 +260,7 @@ impl ConnCfg {
        aux: MetricsAuxInfo,
        timeout: Duration,
    ) -> Result<PostgresConnection, ConnectionError> {
-        let pause = ctx.latency_timer.pause(crate::metrics::Waiting::Compute);
        let (socket_addr, stream, host) = self.connect_raw(timeout).await?;
-        drop(pause);

        let tls_connector = native_tls::TlsConnector::builder()
            .danger_accept_invalid_certs(allow_self_signed_compute)
@@ -272,9 +270,7 @@ impl ConnCfg {
        let tls = MakeTlsConnect::<tokio::net::TcpStream>::make_tls_connect(&mut mk_tls, host)?;

        // connect_raw() will not use TLS if sslmode is "disable"
-        let pause = ctx.latency_timer.pause(crate::metrics::Waiting::Compute);
        let (client, connection) = self.0.connect_raw(stream, tls).await?;
-        drop(pause);
        tracing::Span::current().record("pid", &tracing::field::display(client.get_process_id()));
        let stream = connection.stream.into_inner();

--- a/proxy/src/config.rs
+++ b/proxy/src/config.rs
@@ -33,8 +33,6 @@ pub struct ProxyConfig {
    pub region: String,
    pub handshake_timeout: Duration,
    pub aws_region: String,
-    pub wake_compute_retry_config: RetryConfig,
-    pub connect_to_compute_retry_config: RetryConfig,
 }

 #[derive(Debug)]
@@ -519,59 +517,6 @@ impl FromStr for ProjectInfoCacheOptions {
    }
 }

-/// This is a config for connect to compute and wake compute.
-#[derive(Clone, Copy, Debug)]
-pub struct RetryConfig {
-    /// Number of times we should retry.
-    pub max_retries: u32,
-    /// Retry duration is base_delay * backoff_factor ^ n, where n starts at 0
-    pub base_delay: tokio::time::Duration,
-    /// Exponential base for retry wait duration
-    pub backoff_factor: f64,
-}
-
-impl RetryConfig {
-    /// Default options for RetryConfig.
-
-    /// Total delay for 8 retries with 100ms base delay and 1.6 backoff factor is about 7s.
-    pub const CONNECT_TO_COMPUTE_DEFAULT_VALUES: &'static str =
-        "num_retries=8,base_retry_wait_duration=100ms,retry_wait_exponent_base=1.6";
-    /// Total delay for 8 retries with 100ms base delay and 1.6 backoff factor is about 7s.
-    /// Cplane has timeout of 60s on each request. 8m7s in total.
-    pub const WAKE_COMPUTE_DEFAULT_VALUES: &'static str =
-        "num_retries=8,base_retry_wait_duration=100ms,retry_wait_exponent_base=1.6";
-
-    /// Parse retry options passed via cmdline.
-    /// Example: [`Self::CONNECT_TO_COMPUTE_DEFAULT_VALUES`].
-    pub fn parse(options: &str) -> anyhow::Result<Self> {
-        let mut num_retries = None;
-        let mut base_retry_wait_duration = None;
-        let mut retry_wait_exponent_base = None;
-
-        for option in options.split(',') {
-            let (key, value) = option
-                .split_once('=')
-                .with_context(|| format!("bad key-value pair: {option}"))?;
-
-            match key {
-                "num_retries" => num_retries = Some(value.parse()?),
-                "base_retry_wait_duration" => {
-                    base_retry_wait_duration = Some(humantime::parse_duration(value)?)
-                }
-                "retry_wait_exponent_base" => retry_wait_exponent_base = Some(value.parse()?),
-                unknown => bail!("unknown key: {unknown}"),
-            }
-        }
-
-        Ok(Self {
-            max_retries: num_retries.context("missing `num_retries`")?,
-            base_delay: base_retry_wait_duration.context("missing `base_retry_wait_duration`")?,
-            backoff_factor: retry_wait_exponent_base
-                .context("missing `retry_wait_exponent_base`")?,
-        })
-    }
-}
-
 /// Helper for cmdline cache options parsing.
 pub struct WakeComputeLockOptions {
    /// The number of shards the lock map should have
--- a/proxy/src/context.rs
+++ b/proxy/src/context.rs
@@ -20,8 +20,7 @@ use self::parquet::RequestData;

 pub mod parquet;

-pub static LOG_CHAN: OnceCell<mpsc::WeakUnboundedSender<RequestData>> = OnceCell::new();
-pub static LOG_CHAN_DISCONNECT: OnceCell<mpsc::WeakUnboundedSender<RequestData>> = OnceCell::new();
+static LOG_CHAN: OnceCell<mpsc::WeakUnboundedSender<RequestData>> = OnceCell::new();

 /// Context data for a single request to connect to a database.
 ///
@@ -50,12 +49,9 @@ pub struct RequestMonitoring {
    // extra
    // This sender is here to keep the request monitoring channel open while requests are taking place.
    sender: Option<mpsc::UnboundedSender<RequestData>>,
-    // This sender is only used to log the length of session in case of success.
-    disconnect_sender: Option<mpsc::UnboundedSender<RequestData>>,
    pub latency_timer: LatencyTimer,
    // Whether proxy decided that it's not a valid endpoint end rejected it before going to cplane.
    rejected: Option<bool>,
-    disconnect_timestamp: Option<chrono::DateTime<Utc>>,
 }

 #[derive(Clone, Debug)]
@@ -104,9 +100,7 @@ impl RequestMonitoring {
            cold_start_info: ColdStartInfo::Unknown,

            sender: LOG_CHAN.get().and_then(|tx| tx.upgrade()),
-            disconnect_sender: LOG_CHAN_DISCONNECT.get().and_then(|tx| tx.upgrade()),
            latency_timer: LatencyTimer::new(protocol),
-            disconnect_timestamp: None,
        }
    }

@@ -196,7 +190,11 @@ impl RequestMonitoring {
        self.success = true;
    }

-    pub fn log_connect(&mut self) {
+    pub fn log(self) {}
+}
+
+impl Drop for RequestMonitoring {
+    fn drop(&mut self) {
        let outcome = if self.success {
            ConnectOutcome::Success
        } else {
@@ -228,23 +226,4 @@ impl RequestMonitoring {
            let _: Result<(), _> = tx.send(RequestData::from(&*self));
        }
    }
-
-    fn log_disconnect(&mut self) {
-        // If we are here, it's guaranteed that the user successfully connected to the endpoint.
-        // Here we log the length of the session.
-        self.disconnect_timestamp = Some(Utc::now());
-        if let Some(tx) = self.disconnect_sender.take() {
-            let _: Result<(), _> = tx.send(RequestData::from(&*self));
-        }
-    }
-}
-
-impl Drop for RequestMonitoring {
-    fn drop(&mut self) {
-        if self.sender.is_some() {
-            self.log_connect();
-        } else {
-            self.log_disconnect();
-        }
-    }
 }
--- a/proxy/src/context/parquet.rs
+++ b/proxy/src/context/parquet.rs
@@ -19,10 +19,7 @@ use tokio_util::sync::CancellationToken;
 use tracing::{debug, info, Span};
 use utils::backoff;

-use crate::{
-    config::{remote_storage_from_toml, OptRemoteStorageConfig},
-    context::LOG_CHAN_DISCONNECT,
-};
+use crate::config::{remote_storage_from_toml, OptRemoteStorageConfig};

 use super::{RequestMonitoring, LOG_CHAN};

@@ -34,9 +31,6 @@ pub struct ParquetUploadArgs {
    #[clap(long, default_value = "{}", value_parser = remote_storage_from_toml)]
    parquet_upload_remote_storage: OptRemoteStorageConfig,

-    #[clap(long, default_value = "{}", value_parser = remote_storage_from_toml)]
-    parquet_upload_disconnect_events_remote_storage: OptRemoteStorageConfig,
-
    /// How many rows to include in a row group
    #[clap(long, default_value_t = 8192)]
    parquet_upload_row_group_size: usize,
@@ -97,8 +91,6 @@ pub struct RequestData {
    /// Tracks time from session start (HTTP request/libpq TCP handshake)
    /// Through to success/failure
    duration_us: u64,
-    /// If the session was successful after the disconnect, will be created one more event with filled `disconnect_timestamp`.
-    disconnect_timestamp: Option<chrono::NaiveDateTime>,
 }

 impl From<&RequestMonitoring> for RequestData {
@@ -128,7 +120,6 @@ impl From<&RequestMonitoring> for RequestData {
                .elapsed()
                .unwrap_or_default()
                .as_micros() as u64, // 584 millenia... good enough
-            disconnect_timestamp: value.disconnect_timestamp.map(|x| x.naive_utc()),
        }
    }
 }
@@ -150,9 +141,8 @@ pub async fn worker(
    LOG_CHAN.set(tx.downgrade()).unwrap();

    // setup row stream that will close on cancellation
-    let cancellation_token2 = cancellation_token.clone();
    tokio::spawn(async move {
-        cancellation_token2.cancelled().await;
+        cancellation_token.cancelled().await;
        // dropping this sender will cause the channel to close only once
        // all the remaining inflight requests have been completed.
        drop(tx);
@@ -177,38 +167,9 @@ pub async fn worker(
        test_remote_failures: 0,
    };

-    // TODO(anna): consider moving this to a separate function.
-    if let Some(disconnect_events_storage_config) =
-        config.parquet_upload_disconnect_events_remote_storage
-    {
-        let (tx_disconnect, mut rx_disconnect) = mpsc::unbounded_channel();
-        LOG_CHAN_DISCONNECT.set(tx_disconnect.downgrade()).unwrap();
-
-        // setup row stream that will close on cancellation
-        tokio::spawn(async move {
-            cancellation_token.cancelled().await;
-            // dropping this sender will cause the channel to close only once
-            // all the remaining inflight requests have been completed.
-            drop(tx_disconnect);
-        });
-        let rx_disconnect = futures::stream::poll_fn(move |cx| rx_disconnect.poll_recv(cx));
-        let rx_disconnect = rx_disconnect.map(RequestData::from);
-
-        let storage_disconnect =
-            GenericRemoteStorage::from_config(&disconnect_events_storage_config)
-                .context("remote storage for disconnect events init")?;
-        let parquet_config_disconnect = parquet_config.clone();
-        tokio::try_join!(
-            worker_inner(storage, rx, parquet_config),
-            worker_inner(storage_disconnect, rx_disconnect, parquet_config_disconnect)
-        )
-        .map(|_| ())
-    } else {
-        worker_inner(storage, rx, parquet_config).await
-    }
+    worker_inner(storage, rx, parquet_config).await
 }

-#[derive(Clone, Debug)]
 struct ParquetConfig {
    propeties: WriterPropertiesPtr,
    rows_per_group: usize,
@@ -452,7 +413,6 @@ mod tests {
                    )
                    .unwrap(),
                    max_keys_per_list_response: DEFAULT_MAX_KEYS_PER_LIST_RESPONSE,
-                    upload_storage_class: None,
                }),
                timeout: RemoteStorageConfig::DEFAULT_TIMEOUT,
            })
@@ -491,7 +451,6 @@ mod tests {
            success: rng.gen(),
            cold_start_info: "no",
            duration_us: rng.gen_range(0..30_000_000),
-            disconnect_timestamp: None,
        }
    }

@@ -560,15 +519,15 @@ mod tests {
        assert_eq!(
            file_stats,
            [
-                (1315008, 3, 6000),
-                (1315001, 3, 6000),
-                (1315061, 3, 6000),
-                (1315018, 3, 6000),
-                (1315148, 3, 6000),
-                (1314990, 3, 6000),
-                (1314782, 3, 6000),
-                (1315018, 3, 6000),
-                (438575, 1, 2000)
+                (1314385, 3, 6000),
+                (1314378, 3, 6000),
+                (1314438, 3, 6000),
+                (1314395, 3, 6000),
+                (1314525, 3, 6000),
+                (1314367, 3, 6000),
+                (1314159, 3, 6000),
+                (1314395, 3, 6000),
+                (438352, 1, 2000)
            ]
        );

@@ -598,11 +557,11 @@ mod tests {
        assert_eq!(
            file_stats,
            [
-                (1221738, 5, 10000),
-                (1227888, 5, 10000),
-                (1229682, 5, 10000),
-                (1229044, 5, 10000),
-                (1220322, 5, 10000)
+                (1220633, 5, 10000),
+                (1226783, 5, 10000),
+                (1228577, 5, 10000),
+                (1227939, 5, 10000),
+                (1219217, 5, 10000)
            ]
        );

@@ -634,11 +593,11 @@ mod tests {
        assert_eq!(
            file_stats,
            [
-                (1207385, 5, 10000),
-                (1207116, 5, 10000),
-                (1207409, 5, 10000),
-                (1207397, 5, 10000),
-                (1207652, 5, 10000)
+                (1206280, 5, 10000),
+                (1206011, 5, 10000),
+                (1206304, 5, 10000),
+                (1206292, 5, 10000),
+                (1206547, 5, 10000)
            ]
        );

@@ -663,15 +622,15 @@ mod tests {
        assert_eq!(
            file_stats,
            [
-                (1315008, 3, 6000),
-                (1315001, 3, 6000),
-                (1315061, 3, 6000),
-                (1315018, 3, 6000),
-                (1315148, 3, 6000),
-                (1314990, 3, 6000),
-                (1314782, 3, 6000),
-                (1315018, 3, 6000),
-                (438575, 1, 2000)
+                (1314385, 3, 6000),
+                (1314378, 3, 6000),
+                (1314438, 3, 6000),
+                (1314395, 3, 6000),
+                (1314525, 3, 6000),
+                (1314367, 3, 6000),
+                (1314159, 3, 6000),
+                (1314395, 3, 6000),
+                (438352, 1, 2000)
            ]
        );

@@ -708,7 +667,7 @@ mod tests {
        // files are smaller than the size threshold, but they took too long to fill so were flushed early
        assert_eq!(
            file_stats,
-            [(659240, 2, 3001), (658954, 2, 3000), (658750, 2, 2999)]
+            [(658823, 2, 3001), (658537, 2, 3000), (658333, 2, 2999)]
        );

        tmpdir.close().unwrap();
--- a/proxy/src/http/health_server.rs
+++ b/proxy/src/http/health_server.rs
@@ -1,13 +1,17 @@
 use anyhow::{anyhow, bail};
+use camino::Utf8PathBuf;
+use camino_tempfile::Utf8TempDir;
 use hyper::{header::CONTENT_TYPE, Body, Request, Response, StatusCode};
 use measured::{text::BufferedTextEncoder, MetricGroup};
 use metrics::NeonMetrics;
+use once_cell::sync::Lazy;
 use std::{
    convert::Infallible,
+    ffi::CString,
    net::TcpListener,
    sync::{Arc, Mutex},
 };
-use tracing::{info, info_span};
+use tracing::{info, info_span, warn};
 use utils::http::{
    endpoint::{self, request_span},
    error::ApiError,
@@ -21,18 +25,49 @@ async fn status_handler(_: Request<Body>) -> Result<Response<Body>, ApiError> {
    json_response(StatusCode::OK, "")
 }

+async fn prof_dump(_: Request<Body>) -> Result<Response<Body>, ApiError> {
+    static PROF_MIB: Lazy<jemalloc::dump_mib> =
+        Lazy::new(|| jemalloc::dump::mib().expect("could not create prof.dump MIB"));
+    static PROF_DIR: Lazy<Utf8TempDir> =
+        Lazy::new(|| camino_tempfile::tempdir().expect("could not create tempdir"));
+    static PROF_FILE: Lazy<Utf8PathBuf> = Lazy::new(|| PROF_DIR.path().join("prof.dump"));
+    static PROF_FILE0: Lazy<CString> = Lazy::new(|| CString::new(PROF_FILE.as_str()).unwrap());
+    static DUMP_LOCK: Mutex<()> = Mutex::new(());
+
+    tokio::task::spawn_blocking(|| {
+        let _guard = DUMP_LOCK.lock();
+        PROF_MIB
+            .write(&PROF_FILE0)
+            .expect("could not trigger prof.dump");
+        let prof_dump = std::fs::read_to_string(&*PROF_FILE).expect("could not open prof.dump");
+
+        Response::new(Body::from(prof_dump))
+    })
+    .await
+    .map_err(|e| ApiError::InternalServerError(e.into()))
+}
+
 fn make_router(metrics: AppMetrics) -> RouterBuilder<hyper::Body, ApiError> {
    let state = Arc::new(Mutex::new(PrometheusHandler {
        encoder: BufferedTextEncoder::new(),
        metrics,
    }));

-    endpoint::make_router()
+    let mut router = endpoint::make_router()
        .get("/metrics", move |r| {
            let state = state.clone();
            request_span(r, move |b| prometheus_metrics_handler(b, state))
        })
-        .get("/v1/status", status_handler)
+        .get("/v1/status", status_handler);
+
+    let prof_enabled = jemalloc::prof::read().unwrap_or_default();
+    if prof_enabled {
+        warn!("activating jemalloc profiling");
+        jemalloc::active::write(true).unwrap();
+        router = router.get("/v1/jemalloc/prof.dump", prof_dump);
+    }
+
+    router
 }

 pub async fn task_main(
--- a/proxy/src/jemalloc.rs
+++ b/proxy/src/jemalloc.rs
@@ -1,4 +1,4 @@
-use std::marker::PhantomData;
+use std::{ffi::CStr, marker::PhantomData};

 use measured::{
    label::NoLabels,
@@ -9,7 +9,9 @@ use measured::{
    text::TextEncoder,
    LabelGroup, MetricGroup,
 };
-use tikv_jemalloc_ctl::{config, epoch, epoch_mib, stats, version};
+use tikv_jemalloc_ctl::{
+    config, epoch, epoch_mib, raw, stats, version, Access, AsName, MibStr, Name,
+};

 pub struct MetricRecorder {
    epoch: epoch_mib,
@@ -114,3 +116,59 @@ jemalloc_gauge!(mapped, mapped_mib);
 jemalloc_gauge!(metadata, metadata_mib);
 jemalloc_gauge!(resident, resident_mib);
 jemalloc_gauge!(retained, retained_mib);
+
+#[allow(non_camel_case_types)]
+pub struct dump;
+
+impl dump {
+    pub fn mib() -> tikv_jemalloc_ctl::Result<dump_mib> {
+        Ok(dump_mib(b"prof.dump\0".as_slice().name().mib_str()?))
+    }
+}
+
+#[repr(transparent)]
+#[derive(Copy, Clone)]
+#[allow(non_camel_case_types)]
+pub struct dump_mib(pub MibStr<[usize; 2]>);
+
+impl dump_mib {
+    pub fn write(self, value: &'static CStr) -> tikv_jemalloc_ctl::Result<()> {
+        // No support for Access<CStr> yet.
+        // self.0.write(value)
+        let mib = [self.0[0], self.0[1]];
+        raw::write_str_mib(&mib, value.to_bytes_with_nul())
+    }
+}
+
+#[allow(non_camel_case_types)]
+pub struct active;
+
+impl active {
+    pub fn name() -> &'static Name {
+        b"prof.active\0".as_slice().name()
+    }
+}
+
+impl active {
+    pub fn read() -> tikv_jemalloc_ctl::Result<bool> {
+        Self::name().read()
+    }
+    pub fn write(value: bool) -> tikv_jemalloc_ctl::Result<()> {
+        Self::name().write(value)
+    }
+}
+
+#[allow(non_camel_case_types)]
+pub struct prof;
+
+impl prof {
+    pub fn name() -> &'static Name {
+        b"opt.prof\0".as_slice().name()
+    }
+}
+
+impl prof {
+    pub fn read() -> tikv_jemalloc_ctl::Result<bool> {
+        Self::name().read()
+    }
+}
--- a/proxy/src/metrics.rs
+++ b/proxy/src/metrics.rs
@@ -119,10 +119,6 @@ pub struct ProxyMetrics {

    /// Number of invalid endpoints (per protocol, per rejected).
    pub invalid_endpoints_total: CounterVec<InvalidEndpointsSet>,
-
-    /// Number of retries (per outcome, per retry_type).
-    #[metric(metadata = Thresholds::with_buckets([0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0]))]
-    pub retries_metric: HistogramVec<RetriesMetricSet, 9>,
 }

 #[derive(MetricGroup)]
@@ -277,16 +273,13 @@ pub struct ComputeConnectionLatencyGroup {
    protocol: Protocol,
    cold_start_info: ColdStartInfo,
    outcome: ConnectOutcome,
-    component: LatencyComponents,
+    excluded: LatencyExclusions,
 }

 #[derive(FixedCardinalityLabel, Copy, Clone)]
-pub enum LatencyComponents {
+pub enum LatencyExclusions {
    Client,
-    Cplane,
-    Compute,
-    ComputeRetry,
-    Proxy,
+    ClientAndCplane,
 }

 #[derive(FixedCardinalityLabel, Copy, Clone)]
@@ -355,7 +348,6 @@ pub enum Waiting {
    Cplane,
    Client,
    Compute,
-    RetryTimeout,
 }

 #[derive(Default)]
@@ -363,7 +355,6 @@ struct Accumulated {
    cplane: time::Duration,
    client: time::Duration,
    compute: time::Duration,
-    retry: time::Duration,
 }

 pub struct LatencyTimer {
@@ -426,7 +417,6 @@ impl Drop for LatencyTimerPause<'_> {
            Waiting::Cplane => self.timer.accumulated.cplane += dur,
            Waiting::Client => self.timer.accumulated.client += dur,
            Waiting::Compute => self.timer.accumulated.compute += dur,
-            Waiting::RetryTimeout => self.timer.accumulated.retry += dur,
        }
    }
 }
@@ -446,63 +436,29 @@ impl Drop for LatencyTimer {

        let metric = &Metrics::get().proxy.compute_connection_latency_seconds;

-        // client only latency
+        // Excluding client communication from the accumulated time.
        metric.observe(
            ComputeConnectionLatencyGroup {
                protocol: self.protocol,
                cold_start_info: self.cold_start_info,
                outcome: self.outcome,
-                component: LatencyComponents::Client,
+                excluded: LatencyExclusions::Client,
            },
-            self.accumulated.client.as_secs_f64(),
+            duration
+                .saturating_sub(self.accumulated.client)
+                .as_secs_f64(),
        );

-        // cplane only latency
+        // Exclude client and cplane communication from the accumulated time.
+        let accumulated_total = self.accumulated.client + self.accumulated.cplane;
        metric.observe(
            ComputeConnectionLatencyGroup {
                protocol: self.protocol,
                cold_start_info: self.cold_start_info,
                outcome: self.outcome,
-                component: LatencyComponents::Cplane,
+                excluded: LatencyExclusions::ClientAndCplane,
            },
-            self.accumulated.cplane.as_secs_f64(),
-        );
-
-        // compute connect only latency
-        metric.observe(
-            ComputeConnectionLatencyGroup {
-                protocol: self.protocol,
-                cold_start_info: self.cold_start_info,
-                outcome: self.outcome,
-                component: LatencyComponents::Compute,
-            },
-            self.accumulated.compute.as_secs_f64(),
-        );
-
-        // compute failure retry latency
-        metric.observe(
-            ComputeConnectionLatencyGroup {
-                protocol: self.protocol,
-                cold_start_info: self.cold_start_info,
-                outcome: self.outcome,
-                component: LatencyComponents::ComputeRetry,
-            },
-            self.accumulated.retry.as_secs_f64(),
-        );
-
-        // proxy only latency, removing client+cplane+compute+retry from the total
-        let accumulated = self.accumulated.client
-            + self.accumulated.cplane
-            + self.accumulated.compute
-            + self.accumulated.retry;
-        metric.observe(
-            ComputeConnectionLatencyGroup {
-                protocol: self.protocol,
-                cold_start_info: self.cold_start_info,
-                outcome: self.outcome,
-                component: LatencyComponents::Proxy,
-            },
-            duration.saturating_sub(accumulated).as_secs_f64(),
+            duration.saturating_sub(accumulated_total).as_secs_f64(),
        );
    }
 }
@@ -524,16 +480,3 @@ pub struct InvalidEndpointsGroup {
    pub rejected: Bool,
    pub outcome: ConnectOutcome,
 }
-
-#[derive(LabelGroup)]
-#[label(set = RetriesMetricSet)]
-pub struct RetriesMetricGroup {
-    pub outcome: ConnectOutcome,
-    pub retry_type: RetryType,
-}
-
-#[derive(FixedCardinalityLabel, Clone, Copy, Debug)]
-pub enum RetryType {
-    WakeCompute,
-    ConnectToCompute,
-}
--- a/proxy/src/protocol2.rs
+++ b/proxy/src/protocol2.rs
@@ -1,26 +1,42 @@
 //! Proxy Protocol V2 implementation

 use std::{
+    future::{poll_fn, Future},
    io,
    net::SocketAddr,
-    pin::Pin,
-    task::{Context, Poll},
+    pin::{pin, Pin},
+    task::{ready, Context, Poll},
 };

-use bytes::BytesMut;
+use bytes::{Buf, BytesMut};
+use hyper::server::conn::AddrIncoming;
 use pin_project_lite::pin_project;
 use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, ReadBuf};

+pub struct ProxyProtocolAccept {
+    pub incoming: AddrIncoming,
+    pub protocol: &'static str,
+}
+
 pin_project! {
-    /// A chained [`AsyncRead`] with [`AsyncWrite`] passthrough
-    pub struct ChainRW<T> {
+    pub struct WithClientIp<T> {
        #[pin]
        pub inner: T,
        buf: BytesMut,
+        tlv_bytes: u16,
+        state: ProxyParse,
    }
 }

-impl<T: AsyncWrite> AsyncWrite for ChainRW<T> {
+#[derive(Clone, PartialEq, Debug)]
+enum ProxyParse {
+    NotStarted,
+
+    Finished(SocketAddr),
+    None,
+}
+
+impl<T: AsyncWrite> AsyncWrite for WithClientIp<T> {
    #[inline]
    fn poll_write(
        self: Pin<&mut Self>,
@@ -55,174 +71,267 @@ impl<T: AsyncWrite> AsyncWrite for ChainRW<T> {
    }
 }

+impl<T> WithClientIp<T> {
+    pub fn new(inner: T) -> Self {
+        WithClientIp {
+            inner,
+            buf: BytesMut::with_capacity(128),
+            tlv_bytes: 0,
+            state: ProxyParse::NotStarted,
+        }
+    }
+
+    pub fn client_addr(&self) -> Option<SocketAddr> {
+        match self.state {
+            ProxyParse::Finished(socket) => Some(socket),
+            _ => None,
+        }
+    }
+}
+
+impl<T: AsyncRead + Unpin> WithClientIp<T> {
+    pub async fn wait_for_addr(&mut self) -> io::Result<Option<SocketAddr>> {
+        match self.state {
+            ProxyParse::NotStarted => {
+                let mut pin = Pin::new(&mut *self);
+                let addr = poll_fn(|cx| pin.as_mut().poll_client_ip(cx)).await?;
+                match addr {
+                    Some(addr) => self.state = ProxyParse::Finished(addr),
+                    None => self.state = ProxyParse::None,
+                }
+                Ok(addr)
+            }
+            ProxyParse::Finished(addr) => Ok(Some(addr)),
+            ProxyParse::None => Ok(None),
+        }
+    }
+}
+
 /// Proxy Protocol Version 2 Header
 const HEADER: [u8; 12] = [
    0x0D, 0x0A, 0x0D, 0x0A, 0x00, 0x0D, 0x0A, 0x51, 0x55, 0x49, 0x54, 0x0A,
 ];

-pub async fn read_proxy_protocol<T: AsyncRead + Unpin>(
-    mut read: T,
-) -> std::io::Result<(ChainRW<T>, Option<SocketAddr>)> {
-    let mut buf = BytesMut::with_capacity(128);
-    while buf.len() < 16 {
-        let bytes_read = read.read_buf(&mut buf).await?;
+impl<T: AsyncRead> WithClientIp<T> {
+    /// implementation of <https://www.haproxy.org/download/2.4/doc/proxy-protocol.txt>
+    /// Version 2 (Binary Format)
+    fn poll_client_ip(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+    ) -> Poll<io::Result<Option<SocketAddr>>> {
+        // The binary header format starts with a constant 12 bytes block containing the protocol signature :
+        //    \x0D \x0A \x0D \x0A \x00 \x0D \x0A \x51 \x55 \x49 \x54 \x0A
+        while self.buf.len() < 16 {
+            let mut this = self.as_mut().project();
+            let bytes_read = pin!(this.inner.read_buf(this.buf)).poll(cx)?;

-        // exit for bad header
-        let len = usize::min(buf.len(), HEADER.len());
-        if buf[..len] != HEADER[..len] {
-            return Ok((ChainRW { inner: read, buf }, None));
+            // exit for bad header
+            let len = usize::min(self.buf.len(), HEADER.len());
+            if self.buf[..len] != HEADER[..len] {
+                return Poll::Ready(Ok(None));
+            }
+
+            // if no more bytes available then exit
+            if ready!(bytes_read) == 0 {
+                return Poll::Ready(Ok(None));
+            };
        }

-        // if no more bytes available then exit
-        if bytes_read == 0 {
-            return Ok((ChainRW { inner: read, buf }, None));
-        };
-    }
-
-    let header = buf.split_to(16);
-
-    // The next byte (the 13th one) is the protocol version and command.
-    // The highest four bits contains the version. As of this specification, it must
-    // always be sent as \x2 and the receiver must only accept this value.
-    let vc = header[12];
-    let version = vc >> 4;
-    let command = vc & 0b1111;
-    if version != 2 {
-        return Err(io::Error::new(
-            io::ErrorKind::Other,
-            "invalid proxy protocol version. expected version 2",
-        ));
-    }
-    match command {
-        // the connection was established on purpose by the proxy
-        // without being relayed. The connection endpoints are the sender and the
-        // receiver. Such connections exist when the proxy sends health-checks to the
-        // server. The receiver must accept this connection as valid and must use the
-        // real connection endpoints and discard the protocol block including the
-        // family which is ignored.
-        0 => {}
-        // the connection was established on behalf of another node,
-        // and reflects the original connection endpoints. The receiver must then use
-        // the information provided in the protocol block to get original the address.
-        1 => {}
-        // other values are unassigned and must not be emitted by senders. Receivers
-        // must drop connections presenting unexpected values here.
-        _ => {
-            return Err(io::Error::new(
+        // The next byte (the 13th one) is the protocol version and command.
+        // The highest four bits contains the version. As of this specification, it must
+        // always be sent as \x2 and the receiver must only accept this value.
+        let vc = self.buf[12];
+        let version = vc >> 4;
+        let command = vc & 0b1111;
+        if version != 2 {
+            return Poll::Ready(Err(io::Error::new(
                io::ErrorKind::Other,
-                "invalid proxy protocol command. expected local (0) or proxy (1)",
-            ))
+                "invalid proxy protocol version. expected version 2",
+            )));
        }
-    };
+        match command {
+            // the connection was established on purpose by the proxy
+            // without being relayed. The connection endpoints are the sender and the
+            // receiver. Such connections exist when the proxy sends health-checks to the
+            // server. The receiver must accept this connection as valid and must use the
+            // real connection endpoints and discard the protocol block including the
+            // family which is ignored.
+            0 => {}
+            // the connection was established on behalf of another node,
+            // and reflects the original connection endpoints. The receiver must then use
+            // the information provided in the protocol block to get original the address.
+            1 => {}
+            // other values are unassigned and must not be emitted by senders. Receivers
+            // must drop connections presenting unexpected values here.
+            _ => {
+                return Poll::Ready(Err(io::Error::new(
+                    io::ErrorKind::Other,
+                    "invalid proxy protocol command. expected local (0) or proxy (1)",
+                )))
+            }
+        };

-    // The 14th byte contains the transport protocol and address family. The highest 4
-    // bits contain the address family, the lowest 4 bits contain the protocol.
-    let ft = header[13];
-    let address_length = match ft {
-        // - \x11 : TCP over IPv4 : the forwarded connection uses TCP over the AF_INET
-        //   protocol family. Address length is 2*4 + 2*2 = 12 bytes.
-        // - \x12 : UDP over IPv4 : the forwarded connection uses UDP over the AF_INET
-        //   protocol family. Address length is 2*4 + 2*2 = 12 bytes.
-        0x11 | 0x12 => 12,
-        // - \x21 : TCP over IPv6 : the forwarded connection uses TCP over the AF_INET6
-        //   protocol family. Address length is 2*16 + 2*2 = 36 bytes.
-        // - \x22 : UDP over IPv6 : the forwarded connection uses UDP over the AF_INET6
-        //   protocol family. Address length is 2*16 + 2*2 = 36 bytes.
-        0x21 | 0x22 => 36,
-        // unspecified or unix stream. ignore the addresses
-        _ => 0,
-    };
+        // The 14th byte contains the transport protocol and address family. The highest 4
+        // bits contain the address family, the lowest 4 bits contain the protocol.
+        let ft = self.buf[13];
+        let address_length = match ft {
+            // - \x11 : TCP over IPv4 : the forwarded connection uses TCP over the AF_INET
+            //   protocol family. Address length is 2*4 + 2*2 = 12 bytes.
+            // - \x12 : UDP over IPv4 : the forwarded connection uses UDP over the AF_INET
+            //   protocol family. Address length is 2*4 + 2*2 = 12 bytes.
+            0x11 | 0x12 => 12,
+            // - \x21 : TCP over IPv6 : the forwarded connection uses TCP over the AF_INET6
+            //   protocol family. Address length is 2*16 + 2*2 = 36 bytes.
+            // - \x22 : UDP over IPv6 : the forwarded connection uses UDP over the AF_INET6
+            //   protocol family. Address length is 2*16 + 2*2 = 36 bytes.
+            0x21 | 0x22 => 36,
+            // unspecified or unix stream. ignore the addresses
+            _ => 0,
+        };

-    // The 15th and 16th bytes is the address length in bytes in network endian order.
-    // It is used so that the receiver knows how many address bytes to skip even when
-    // it does not implement the presented protocol. Thus the length of the protocol
-    // header in bytes is always exactly 16 + this value. When a sender presents a
-    // LOCAL connection, it should not present any address so it sets this field to
-    // zero. Receivers MUST always consider this field to skip the appropriate number
-    // of bytes and must not assume zero is presented for LOCAL connections. When a
-    // receiver accepts an incoming connection showing an UNSPEC address family or
-    // protocol, it may or may not decide to log the address information if present.
-    let remaining_length = u16::from_be_bytes(header[14..16].try_into().unwrap());
-    if remaining_length < address_length {
-        return Err(io::Error::new(
-            io::ErrorKind::Other,
-            "invalid proxy protocol length. not enough to fit requested IP addresses",
-        ));
-    }
-    drop(header);
-
-    while buf.len() < remaining_length as usize {
-        if read.read_buf(&mut buf).await? == 0 {
-            return Err(io::Error::new(
-                io::ErrorKind::UnexpectedEof,
-                "stream closed while waiting for proxy protocol addresses",
-            ));
+        // The 15th and 16th bytes is the address length in bytes in network endian order.
+        // It is used so that the receiver knows how many address bytes to skip even when
+        // it does not implement the presented protocol. Thus the length of the protocol
+        // header in bytes is always exactly 16 + this value. When a sender presents a
+        // LOCAL connection, it should not present any address so it sets this field to
+        // zero. Receivers MUST always consider this field to skip the appropriate number
+        // of bytes and must not assume zero is presented for LOCAL connections. When a
+        // receiver accepts an incoming connection showing an UNSPEC address family or
+        // protocol, it may or may not decide to log the address information if present.
+        let remaining_length = u16::from_be_bytes(self.buf[14..16].try_into().unwrap());
+        if remaining_length < address_length {
+            return Poll::Ready(Err(io::Error::new(
+                io::ErrorKind::Other,
+                "invalid proxy protocol length. not enough to fit requested IP addresses",
+            )));
        }
+
+        while self.buf.len() < 16 + address_length as usize {
+            let mut this = self.as_mut().project();
+            if ready!(pin!(this.inner.read_buf(this.buf)).poll(cx)?) == 0 {
+                return Poll::Ready(Err(io::Error::new(
+                    io::ErrorKind::UnexpectedEof,
+                    "stream closed while waiting for proxy protocol addresses",
+                )));
+            }
+        }
+
+        let this = self.as_mut().project();
+
+        // we are sure this is a proxy protocol v2 entry and we have read all the bytes we need
+        // discard the header we have parsed
+        this.buf.advance(16);
+
+        // Starting from the 17th byte, addresses are presented in network byte order.
+        // The address order is always the same :
+        //   - source layer 3 address in network byte order
+        //   - destination layer 3 address in network byte order
+        //   - source layer 4 address if any, in network byte order (port)
+        //   - destination layer 4 address if any, in network byte order (port)
+        let addresses = this.buf.split_to(address_length as usize);
+        let socket = match address_length {
+            12 => {
+                let src_addr: [u8; 4] = addresses[0..4].try_into().unwrap();
+                let src_port = u16::from_be_bytes(addresses[8..10].try_into().unwrap());
+                Some(SocketAddr::from((src_addr, src_port)))
+            }
+            36 => {
+                let src_addr: [u8; 16] = addresses[0..16].try_into().unwrap();
+                let src_port = u16::from_be_bytes(addresses[32..34].try_into().unwrap());
+                Some(SocketAddr::from((src_addr, src_port)))
+            }
+            _ => None,
+        };
+
+        *this.tlv_bytes = remaining_length - address_length;
+        self.as_mut().skip_tlv_inner();
+
+        Poll::Ready(Ok(socket))
    }

-    // Starting from the 17th byte, addresses are presented in network byte order.
-    // The address order is always the same :
-    //   - source layer 3 address in network byte order
-    //   - destination layer 3 address in network byte order
-    //   - source layer 4 address if any, in network byte order (port)
-    //   - destination layer 4 address if any, in network byte order (port)
-    let addresses = buf.split_to(remaining_length as usize);
-    let socket = match address_length {
-        12 => {
-            let src_addr: [u8; 4] = addresses[0..4].try_into().unwrap();
-            let src_port = u16::from_be_bytes(addresses[8..10].try_into().unwrap());
-            Some(SocketAddr::from((src_addr, src_port)))
+    #[cold]
+    fn read_ip(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        let ip = ready!(self.as_mut().poll_client_ip(cx)?);
+        match ip {
+            Some(x) => *self.as_mut().project().state = ProxyParse::Finished(x),
+            None => *self.as_mut().project().state = ProxyParse::None,
        }
-        36 => {
-            let src_addr: [u8; 16] = addresses[0..16].try_into().unwrap();
-            let src_port = u16::from_be_bytes(addresses[32..34].try_into().unwrap());
-            Some(SocketAddr::from((src_addr, src_port)))
-        }
-        _ => None,
-    };
+        Poll::Ready(Ok(()))
+    }

-    Ok((ChainRW { inner: read, buf }, socket))
+    #[cold]
+    fn skip_tlv(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        let mut this = self.as_mut().project();
+        // we know that this.buf is empty
+        debug_assert_eq!(this.buf.len(), 0);
+
+        this.buf.reserve((*this.tlv_bytes).clamp(0, 1024) as usize);
+        ready!(pin!(this.inner.read_buf(this.buf)).poll(cx)?);
+        self.skip_tlv_inner();
+
+        Poll::Ready(Ok(()))
+    }
+
+    fn skip_tlv_inner(self: Pin<&mut Self>) {
+        let tlv_bytes_read = match u16::try_from(self.buf.len()) {
+            // we read more than u16::MAX therefore we must have read the full tlv_bytes
+            Err(_) => self.tlv_bytes,
+            // we might not have read the full tlv bytes yet
+            Ok(n) => u16::min(n, self.tlv_bytes),
+        };
+        let this = self.project();
+        *this.tlv_bytes -= tlv_bytes_read;
+        this.buf.advance(tlv_bytes_read as usize);
+    }
 }

-impl<T: AsyncRead> AsyncRead for ChainRW<T> {
+impl<T: AsyncRead> AsyncRead for WithClientIp<T> {
    #[inline]
    fn poll_read(
-        self: Pin<&mut Self>,
+        mut self: Pin<&mut Self>,
        cx: &mut Context<'_>,
        buf: &mut ReadBuf<'_>,
    ) -> Poll<io::Result<()>> {
-        if self.buf.is_empty() {
-            self.project().inner.poll_read(cx, buf)
-        } else {
-            self.read_from_buf(buf)
-        }
-    }
-}
+        // I'm assuming these 3 comparisons will be easy to branch predict.
+        // especially with the cold attributes
+        // which should make this read wrapper almost invisible
+
+        if let ProxyParse::NotStarted = self.state {
+            ready!(self.as_mut().read_ip(cx)?);
+        }
+
+        while self.tlv_bytes > 0 {
+            ready!(self.as_mut().skip_tlv(cx)?)
+        }

-impl<T: AsyncRead> ChainRW<T> {
-    #[cold]
-    fn read_from_buf(self: Pin<&mut Self>, buf: &mut ReadBuf<'_>) -> Poll<io::Result<()>> {
-        debug_assert!(!self.buf.is_empty());
        let this = self.project();
-
-        let write = usize::min(this.buf.len(), buf.remaining());
-        let slice = this.buf.split_to(write).freeze();
-        buf.put_slice(&slice);
-
-        // reset the allocation so it can be freed
        if this.buf.is_empty() {
-            *this.buf = BytesMut::new();
-        }
+            this.inner.poll_read(cx, buf)
+        } else {
+            // we know that tlv_bytes is 0
+            debug_assert_eq!(*this.tlv_bytes, 0);

-        Poll::Ready(Ok(()))
+            let write = usize::min(this.buf.len(), buf.remaining());
+            let slice = this.buf.split_to(write).freeze();
+            buf.put_slice(&slice);
+
+            // reset the allocation so it can be freed
+            if this.buf.is_empty() {
+                *this.buf = BytesMut::new();
+            }
+
+            Poll::Ready(Ok(()))
+        }
    }
 }

 #[cfg(test)]
 mod tests {
+    use std::pin::pin;
+
    use tokio::io::AsyncReadExt;

-    use crate::protocol2::read_proxy_protocol;
+    use crate::protocol2::{ProxyParse, WithClientIp};

    #[tokio::test]
    async fn test_ipv4() {
@@ -244,15 +353,16 @@ mod tests {

        let extra_data = [0x55; 256];

-        let (mut read, addr) = read_proxy_protocol(header.chain(extra_data.as_slice()))
-            .await
-            .unwrap();
+        let mut read = pin!(WithClientIp::new(header.chain(extra_data.as_slice())));

        let mut bytes = vec![];
        read.read_to_end(&mut bytes).await.unwrap();

        assert_eq!(bytes, extra_data);
-        assert_eq!(addr, Some(([127, 0, 0, 1], 65535).into()));
+        assert_eq!(
+            read.state,
+            ProxyParse::Finished(([127, 0, 0, 1], 65535).into())
+        );
    }

    #[tokio::test]
@@ -275,17 +385,17 @@ mod tests {

        let extra_data = [0x55; 256];

-        let (mut read, addr) = read_proxy_protocol(header.chain(extra_data.as_slice()))
-            .await
-            .unwrap();
+        let mut read = pin!(WithClientIp::new(header.chain(extra_data.as_slice())));

        let mut bytes = vec![];
        read.read_to_end(&mut bytes).await.unwrap();

        assert_eq!(bytes, extra_data);
        assert_eq!(
-            addr,
-            Some(([15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0], 257).into())
+            read.state,
+            ProxyParse::Finished(
+                ([15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0], 257).into()
+            )
        );
    }

@@ -293,24 +403,24 @@ mod tests {
    async fn test_invalid() {
        let data = [0x55; 256];

-        let (mut read, addr) = read_proxy_protocol(data.as_slice()).await.unwrap();
+        let mut read = pin!(WithClientIp::new(data.as_slice()));

        let mut bytes = vec![];
        read.read_to_end(&mut bytes).await.unwrap();
        assert_eq!(bytes, data);
-        assert_eq!(addr, None);
+        assert_eq!(read.state, ProxyParse::None);
    }

    #[tokio::test]
    async fn test_short() {
        let data = [0x55; 10];

-        let (mut read, addr) = read_proxy_protocol(data.as_slice()).await.unwrap();
+        let mut read = pin!(WithClientIp::new(data.as_slice()));

        let mut bytes = vec![];
        read.read_to_end(&mut bytes).await.unwrap();
        assert_eq!(bytes, data);
-        assert_eq!(addr, None);
+        assert_eq!(read.state, ProxyParse::None);
    }

    #[tokio::test]
@@ -336,14 +446,15 @@ mod tests {

        let extra_data = [0xaa; 256];

-        let (mut read, addr) = read_proxy_protocol(header.chain(extra_data.as_slice()))
-            .await
-            .unwrap();
+        let mut read = pin!(WithClientIp::new(header.chain(extra_data.as_slice())));

        let mut bytes = vec![];
        read.read_to_end(&mut bytes).await.unwrap();

        assert_eq!(bytes, extra_data);
-        assert_eq!(addr, Some(([55, 56, 57, 58], 65535).into()));
+        assert_eq!(
+            read.state,
+            ProxyParse::Finished(([55, 56, 57, 58], 65535).into())
+        );
    }
 }
--- a/proxy/src/proxy.rs
+++ b/proxy/src/proxy.rs
@@ -17,7 +17,7 @@ use crate::{
    context::RequestMonitoring,
    error::ReportableError,
    metrics::{Metrics, NumClientConnectionsGuard},
-    protocol2::read_proxy_protocol,
+    protocol2::WithClientIp,
    proxy::handshake::{handshake, HandshakeData},
    stream::{PqStream, Stream},
    EndpointCacheKey,
@@ -88,18 +88,20 @@ pub async fn task_main(
        tracing::info!(protocol = "tcp", %session_id, "accepted new TCP connection");

        connections.spawn(async move {
-            let (socket, peer_addr) = match read_proxy_protocol(socket).await{
-                Ok((socket, Some(addr))) => (socket, addr.ip()),
+            let mut socket = WithClientIp::new(socket);
+            let mut peer_addr = peer_addr.ip();
+            match socket.wait_for_addr().await {
+                Ok(Some(addr)) => peer_addr = addr.ip(),
                Err(e) => {
                    error!("per-client task finished with an error: {e:#}");
                    return;
                }
-                Ok((_socket, None)) if config.require_client_ip => {
+                Ok(None) if config.require_client_ip => {
                    error!("missing required client IP");
                    return;
                }
-                Ok((socket, None)) => (socket, peer_addr.ip())
-            };
+                Ok(None) => {}
+            }

            match socket.inner.set_nodelay(true) {
                Ok(()) => {},
@@ -132,14 +134,16 @@ pub async fn task_main(
                Err(e) => {
                    // todo: log and push to ctx the error kind
                    ctx.set_error_kind(e.get_error_kind());
+                    ctx.log();
                    error!(parent: &span, "per-client task finished with an error: {e:#}");
                }
                Ok(None) => {
                    ctx.set_success();
+                    ctx.log();
                }
                Ok(Some(p)) => {
                    ctx.set_success();
-                    ctx.log_connect();
+                    ctx.log();
                    match p.proxy_pass().instrument(span.clone()).await {
                        Ok(()) => {}
                        Err(e) => {
@@ -304,8 +308,6 @@ pub async fn handle_client<S: AsyncRead + AsyncWrite + Unpin>(
        &TcpMechanism { params: &params },
        &user_info,
        mode.allow_self_signed_compute(config),
-        config.wake_compute_retry_config,
-        config.connect_to_compute_retry_config,
    )
    .or_else(|e| stream.throw_error(e))
    .await?;
--- a/proxy/src/proxy/connect_compute.rs
+++ b/proxy/src/proxy/connect_compute.rs
@@ -1,11 +1,10 @@
 use crate::{
    auth::backend::ComputeCredentialKeys,
    compute::{self, PostgresConnection},
-    config::RetryConfig,
    console::{self, errors::WakeComputeError, CachedNodeInfo, NodeInfo},
    context::RequestMonitoring,
    error::ReportableError,
-    metrics::{ConnectOutcome, ConnectionFailureKind, Metrics, RetriesMetricGroup, RetryType},
+    metrics::{ConnectionFailureKind, Metrics},
    proxy::{
        retry::{retry_after, ShouldRetry},
        wake_compute::wake_compute,
@@ -94,23 +93,19 @@ pub async fn connect_to_compute<M: ConnectMechanism, B: ComputeConnectBackend>(
    mechanism: &M,
    user_info: &B,
    allow_self_signed_compute: bool,
-    wake_compute_retry_config: RetryConfig,
-    connect_to_compute_retry_config: RetryConfig,
 ) -> Result<M::Connection, M::Error>
 where
    M::ConnectError: ShouldRetry + std::fmt::Debug,
    M::Error: From<WakeComputeError>,
 {
    let mut num_retries = 0;
-    let mut node_info =
-        wake_compute(&mut num_retries, ctx, user_info, wake_compute_retry_config).await?;
+    let mut node_info = wake_compute(&mut num_retries, ctx, user_info).await?;
    if let Some(keys) = user_info.get_keys() {
        node_info.set_keys(keys);
    }
    node_info.allow_self_signed_compute = allow_self_signed_compute;
    // let mut node_info = credentials.get_node_info(ctx, user_info).await?;
    mechanism.update_connect_config(&mut node_info.config);
-    let retry_type = RetryType::ConnectToCompute;

    // try once
    let err = match mechanism
@@ -119,13 +114,6 @@ where
    {
        Ok(res) => {
            ctx.latency_timer.success();
-            Metrics::get().proxy.retries_metric.observe(
-                RetriesMetricGroup {
-                    outcome: ConnectOutcome::Success,
-                    retry_type,
-                },
-                num_retries.into(),
-            );
            return Ok(res);
        }
        Err(e) => e,
@@ -133,17 +121,10 @@ where

    error!(error = ?err, "could not connect to compute node");

-    let node_info = if !node_info.cached() || !err.should_retry_database_address() {
+    let node_info = if !node_info.cached() {
        // If we just recieved this from cplane and dodn't get it from cache, we shouldn't retry.
        // Do not need to retrieve a new node_info, just return the old one.
-        if !err.should_retry(num_retries, connect_to_compute_retry_config) {
-            Metrics::get().proxy.retries_metric.observe(
-                RetriesMetricGroup {
-                    outcome: ConnectOutcome::Failed,
-                    retry_type,
-                },
-                num_retries.into(),
-            );
+        if !err.should_retry(num_retries) {
            return Err(err.into());
        }
        node_info
@@ -151,8 +132,7 @@ where
        // if we failed to connect, it's likely that the compute node was suspended, wake a new compute node
        info!("compute node's state has likely changed; requesting a wake-up");
        let old_node_info = invalidate_cache(node_info);
-        let mut node_info =
-            wake_compute(&mut num_retries, ctx, user_info, wake_compute_retry_config).await?;
+        let mut node_info = wake_compute(&mut num_retries, ctx, user_info).await?;
        node_info.reuse_settings(old_node_info);

        mechanism.update_connect_config(&mut node_info.config);
@@ -171,40 +151,21 @@ where
        {
            Ok(res) => {
                ctx.latency_timer.success();
-                Metrics::get().proxy.retries_metric.observe(
-                    RetriesMetricGroup {
-                        outcome: ConnectOutcome::Success,
-                        retry_type,
-                    },
-                    num_retries.into(),
-                );
-                info!(?num_retries, "connected to compute node after");
                return Ok(res);
            }
            Err(e) => {
-                let retriable = e.should_retry(num_retries, connect_to_compute_retry_config);
+                let retriable = e.should_retry(num_retries);
                if !retriable {
                    error!(error = ?e, num_retries, retriable, "couldn't connect to compute node");
-                    Metrics::get().proxy.retries_metric.observe(
-                        RetriesMetricGroup {
-                            outcome: ConnectOutcome::Failed,
-                            retry_type,
-                        },
-                        num_retries.into(),
-                    );
                    return Err(e.into());
                }
                warn!(error = ?e, num_retries, retriable, "couldn't connect to compute node");
            }
        }

-        let wait_duration = retry_after(num_retries, connect_to_compute_retry_config);
+        let wait_duration = retry_after(num_retries);
        num_retries += 1;

-        let pause = ctx
-            .latency_timer
-            .pause(crate::metrics::Waiting::RetryTimeout);
        time::sleep(wait_duration).await;
-        drop(pause);
    }
 }
--- a/proxy/src/proxy/retry.rs
+++ b/proxy/src/proxy/retry.rs
@@ -1,18 +1,21 @@
-use crate::{compute, config::RetryConfig};
+use crate::compute;
 use std::{error::Error, io};
 use tokio::time;

+/// Number of times we should retry the `/proxy_wake_compute` http request.
+/// Retry duration is BASE_RETRY_WAIT_DURATION * RETRY_WAIT_EXPONENT_BASE ^ n, where n starts at 0
+pub const NUM_RETRIES_CONNECT: u32 = 16;
+const BASE_RETRY_WAIT_DURATION: time::Duration = time::Duration::from_millis(25);
+const RETRY_WAIT_EXPONENT_BASE: f64 = std::f64::consts::SQRT_2;
+
 pub trait ShouldRetry {
    fn could_retry(&self) -> bool;
-    fn should_retry(&self, num_retries: u32, config: RetryConfig) -> bool {
+    fn should_retry(&self, num_retries: u32) -> bool {
        match self {
-            _ if num_retries >= config.max_retries => false,
+            _ if num_retries >= NUM_RETRIES_CONNECT => false,
            err => err.could_retry(),
        }
    }
-    fn should_retry_database_address(&self) -> bool {
-        true
-    }
 }

 impl ShouldRetry for io::Error {
@@ -36,21 +39,6 @@ impl ShouldRetry for tokio_postgres::error::DbError {
                | &SqlState::SQLCLIENT_UNABLE_TO_ESTABLISH_SQLCONNECTION,
        )
    }
-    fn should_retry_database_address(&self) -> bool {
-        use tokio_postgres::error::SqlState;
-        // Here are errors that happens after the user successfully authenticated to the database.
-        // TODO: there are pgbouncer errors that should be retried, but they are not listed here.
-        !matches!(
-            self.code(),
-            &SqlState::TOO_MANY_CONNECTIONS
-                | &SqlState::OUT_OF_MEMORY
-                | &SqlState::SYNTAX_ERROR
-                | &SqlState::T_R_SERIALIZATION_FAILURE
-                | &SqlState::INVALID_CATALOG_NAME
-                | &SqlState::INVALID_SCHEMA_NAME
-                | &SqlState::INVALID_PARAMETER_VALUE
-        )
-    }
 }

 impl ShouldRetry for tokio_postgres::Error {
@@ -63,15 +51,6 @@ impl ShouldRetry for tokio_postgres::Error {
            false
        }
    }
-    fn should_retry_database_address(&self) -> bool {
-        if let Some(io_err) = self.source().and_then(|x| x.downcast_ref()) {
-            io::Error::should_retry_database_address(io_err)
-        } else if let Some(db_err) = self.source().and_then(|x| x.downcast_ref()) {
-            tokio_postgres::error::DbError::should_retry_database_address(db_err)
-        } else {
-            true
-        }
-    }
 }

 impl ShouldRetry for compute::ConnectionError {
@@ -82,17 +61,8 @@ impl ShouldRetry for compute::ConnectionError {
            _ => false,
        }
    }
-    fn should_retry_database_address(&self) -> bool {
-        match self {
-            compute::ConnectionError::Postgres(err) => err.should_retry_database_address(),
-            compute::ConnectionError::CouldNotConnect(err) => err.should_retry_database_address(),
-            _ => true,
-        }
-    }
 }

-pub fn retry_after(num_retries: u32, config: RetryConfig) -> time::Duration {
-    config
-        .base_delay
-        .mul_f64(config.backoff_factor.powi((num_retries as i32) - 1))
+pub fn retry_after(num_retries: u32) -> time::Duration {
+    BASE_RETRY_WAIT_DURATION.mul_f64(RETRY_WAIT_EXPONENT_BASE.powi((num_retries as i32) - 1))
 }
--- a/proxy/src/proxy/tests.rs
+++ b/proxy/src/proxy/tests.rs
@@ -10,13 +10,13 @@ use super::*;
 use crate::auth::backend::{
    ComputeCredentialKeys, ComputeCredentials, ComputeUserInfo, MaybeOwned, TestBackend,
 };
-use crate::config::{CertResolver, RetryConfig};
+use crate::config::CertResolver;
 use crate::console::caches::NodeInfoCache;
 use crate::console::messages::MetricsAuxInfo;
 use crate::console::provider::{CachedAllowedIps, CachedRoleSecret, ConsoleBackend};
 use crate::console::{self, CachedNodeInfo, NodeInfo};
 use crate::error::ErrorKind;
-use crate::proxy::retry::retry_after;
+use crate::proxy::retry::{retry_after, NUM_RETRIES_CONNECT};
 use crate::{http, sasl, scram, BranchId, EndpointId, ProjectId};
 use anyhow::{bail, Context};
 use async_trait::async_trait;
@@ -174,7 +174,7 @@ async fn dummy_proxy(
    tls: Option<TlsConfig>,
    auth: impl TestAuth + Send,
 ) -> anyhow::Result<()> {
-    let (client, _) = read_proxy_protocol(client).await?;
+    let client = WithClientIp::new(client);
    let mut stream = match handshake(client, tls.as_ref(), false).await? {
        HandshakeData::Startup(stream, _) => stream,
        HandshakeData::Cancel(_) => bail!("cancellation not supported"),
@@ -361,15 +361,11 @@ async fn scram_auth_mock() -> anyhow::Result<()> {
 #[test]
 fn connect_compute_total_wait() {
    let mut total_wait = tokio::time::Duration::ZERO;
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    for num_retries in 1..config.max_retries {
-        total_wait += retry_after(num_retries, config);
+    for num_retries in 1..NUM_RETRIES_CONNECT {
+        total_wait += retry_after(num_retries);
    }
-    assert!(f64::abs(total_wait.as_secs_f64() - 15.0) < 0.1);
+    assert!(total_wait < tokio::time::Duration::from_secs(12));
+    assert!(total_wait > tokio::time::Duration::from_secs(10));
 }

 #[derive(Clone, Copy, Debug)]
@@ -553,12 +549,7 @@ async fn connect_to_compute_success() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![Wake, Connect]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap();
    mechanism.verify();
@@ -571,12 +562,7 @@ async fn connect_to_compute_retry() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![Wake, Retry, Wake, Connect]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap();
    mechanism.verify();
@@ -590,12 +576,7 @@ async fn connect_to_compute_non_retry_1() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![Wake, Retry, Wake, Fail]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap_err();
    mechanism.verify();
@@ -609,12 +590,7 @@ async fn connect_to_compute_non_retry_2() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![Wake, Fail, Wake, Connect]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap();
    mechanism.verify();
@@ -624,32 +600,17 @@ async fn connect_to_compute_non_retry_2() {
 #[tokio::test]
 async fn connect_to_compute_non_retry_3() {
    let _ = env_logger::try_init();
-    tokio::time::pause();
+    assert_eq!(NUM_RETRIES_CONNECT, 16);
    use ConnectAction::*;
    let mut ctx = RequestMonitoring::test();
-    let mechanism =
-        TestConnectMechanism::new(vec![Wake, Retry, Wake, Retry, Retry, Retry, Retry, Retry]);
+    let mechanism = TestConnectMechanism::new(vec![
+        Wake, Retry, Wake, Retry, Retry, Retry, Retry, Retry, Retry, Retry, Retry, Retry, Retry,
+        Retry, Retry, Retry, Retry, Retry, /* the 17th time */ Retry,
+    ]);
    let user_info = helper_create_connect_info(&mechanism);
-    let wake_compute_retry_config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 1,
-        backoff_factor: 2.0,
-    };
-    let connect_to_compute_retry_config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(
-        &mut ctx,
-        &mechanism,
-        &user_info,
-        false,
-        wake_compute_retry_config,
-        connect_to_compute_retry_config,
-    )
-    .await
-    .unwrap_err();
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
+        .await
+        .unwrap_err();
    mechanism.verify();
 }

@@ -661,12 +622,7 @@ async fn wake_retry() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![WakeRetry, Wake, Connect]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap();
    mechanism.verify();
@@ -680,12 +636,7 @@ async fn wake_non_retry() {
    let mut ctx = RequestMonitoring::test();
    let mechanism = TestConnectMechanism::new(vec![WakeRetry, WakeFail]);
    let user_info = helper_create_connect_info(&mechanism);
-    let config = RetryConfig {
-        base_delay: Duration::from_secs(1),
-        max_retries: 5,
-        backoff_factor: 2.0,
-    };
-    connect_to_compute(&mut ctx, &mechanism, &user_info, false, config, config)
+    connect_to_compute(&mut ctx, &mechanism, &user_info, false)
        .await
        .unwrap_err();
    mechanism.verify();
--- a/proxy/src/proxy/wake_compute.rs
+++ b/proxy/src/proxy/wake_compute.rs
@@ -1,14 +1,10 @@
-use crate::config::RetryConfig;
 use crate::console::{errors::WakeComputeError, provider::CachedNodeInfo};
 use crate::context::RequestMonitoring;
-use crate::metrics::{
-    ConnectOutcome, ConnectionFailuresBreakdownGroup, Metrics, RetriesMetricGroup, RetryType,
-    WakeupFailureKind,
-};
+use crate::metrics::{ConnectionFailuresBreakdownGroup, Metrics, WakeupFailureKind};
 use crate::proxy::retry::retry_after;
 use hyper::StatusCode;
 use std::ops::ControlFlow;
-use tracing::{error, info, warn};
+use tracing::{error, warn};

 use super::connect_compute::ComputeConnectBackend;
 use super::retry::ShouldRetry;
@@ -17,48 +13,25 @@ pub async fn wake_compute<B: ComputeConnectBackend>(
    num_retries: &mut u32,
    ctx: &mut RequestMonitoring,
    api: &B,
-    config: RetryConfig,
 ) -> Result<CachedNodeInfo, WakeComputeError> {
-    let retry_type = RetryType::WakeCompute;
    loop {
        let wake_res = api.wake_compute(ctx).await;
-        match handle_try_wake(wake_res, *num_retries, config) {
+        match handle_try_wake(wake_res, *num_retries) {
            Err(e) => {
                error!(error = ?e, num_retries, retriable = false, "couldn't wake compute node");
                report_error(&e, false);
-                Metrics::get().proxy.retries_metric.observe(
-                    RetriesMetricGroup {
-                        outcome: ConnectOutcome::Failed,
-                        retry_type,
-                    },
-                    (*num_retries).into(),
-                );
                return Err(e);
            }
            Ok(ControlFlow::Continue(e)) => {
                warn!(error = ?e, num_retries, retriable = true, "couldn't wake compute node");
                report_error(&e, true);
            }
-            Ok(ControlFlow::Break(n)) => {
-                Metrics::get().proxy.retries_metric.observe(
-                    RetriesMetricGroup {
-                        outcome: ConnectOutcome::Success,
-                        retry_type,
-                    },
-                    (*num_retries).into(),
-                );
-                info!(?num_retries, "compute node woken up after");
-                return Ok(n);
-            }
+            Ok(ControlFlow::Break(n)) => return Ok(n),
        }

-        let wait_duration = retry_after(*num_retries, config);
+        let wait_duration = retry_after(*num_retries);
        *num_retries += 1;
-        let pause = ctx
-            .latency_timer
-            .pause(crate::metrics::Waiting::RetryTimeout);
        tokio::time::sleep(wait_duration).await;
-        drop(pause);
    }
 }

@@ -69,11 +42,10 @@ pub async fn wake_compute<B: ComputeConnectBackend>(
 pub fn handle_try_wake(
    result: Result<CachedNodeInfo, WakeComputeError>,
    num_retries: u32,
-    config: RetryConfig,
 ) -> Result<ControlFlow<CachedNodeInfo, WakeComputeError>, WakeComputeError> {
    match result {
        Err(err) => match &err {
-            WakeComputeError::ApiError(api) if api.should_retry(num_retries, config) => {
+            WakeComputeError::ApiError(api) if api.should_retry(num_retries) => {
                Ok(ControlFlow::Continue(err))
            }
            _ => Err(err),
--- a/proxy/src/serverless.rs
+++ b/proxy/src/serverless.rs
@@ -33,7 +33,7 @@ use crate::cancellation::CancellationHandlerMain;
 use crate::config::ProxyConfig;
 use crate::context::RequestMonitoring;
 use crate::metrics::Metrics;
-use crate::protocol2::read_proxy_protocol;
+use crate::protocol2::WithClientIp;
 use crate::proxy::run_until_cancelled;
 use crate::serverless::backend::PoolingBackend;
 use crate::serverless::http_util::{api_error_into_response, json_response};
@@ -158,8 +158,9 @@ async fn connection_handler(
        .guard(crate::metrics::Protocol::Http);

    // handle PROXY protocol
-    let (conn, peer) = match read_proxy_protocol(conn).await {
-        Ok(c) => c,
+    let mut conn = WithClientIp::new(conn);
+    let peer = match conn.wait_for_addr().await {
+        Ok(peer) => peer,
        Err(e) => {
            tracing::error!(?session_id, %peer_addr, "failed to accept TCP connection: invalid PROXY protocol V2 header: {e:#}");
            return;
--- a/proxy/src/serverless/backend.rs
+++ b/proxy/src/serverless/backend.rs
@@ -108,8 +108,6 @@ impl PoolingBackend {
            },
            &backend,
            false, // do not allow self signed compute for http flow
-            self.config.wake_compute_retry_config,
-            self.config.connect_to_compute_retry_config,
        )
        .await
    }
@@ -179,9 +177,7 @@ impl ConnectMechanism for TokioMechanism {
            .dbname(&self.conn_info.dbname)
            .connect_timeout(timeout);

-        let pause = ctx.latency_timer.pause(crate::metrics::Waiting::Compute);
        let (client, connection) = config.connect(tokio_postgres::NoTls).await?;
-        drop(pause);

        tracing::Span::current().record("pid", &tracing::field::display(client.get_process_id()));
        Ok(poll_client(
--- a/proxy/src/serverless/websocket.rs
+++ b/proxy/src/serverless/websocket.rs
@@ -156,15 +156,17 @@ pub async fn serve_websocket(
        Err(e) => {
            // todo: log and push to ctx the error kind
            ctx.set_error_kind(e.get_error_kind());
+            ctx.log();
            Err(e.into())
        }
        Ok(None) => {
            ctx.set_success();
+            ctx.log();
            Ok(())
        }
        Ok(Some(p)) => {
            ctx.set_success();
-            ctx.log_connect();
+            ctx.log();
            p.proxy_pass().await
        }
    }
--- a/s3_scrubber/Cargo.toml
+++ b/s3_scrubber/Cargo.toml
@@ -25,7 +25,6 @@ async-stream.workspace = true
 tokio-stream.workspace = true
 futures-util.workspace = true
 itertools.workspace = true
-camino.workspace = true

 tokio = { workspace = true, features = ["macros", "rt-multi-thread"] }
 chrono = { workspace = true, default-features = false, features = ["clock", "serde"] }
--- a/s3_scrubber/src/lib.rs
+++ b/s3_scrubber/src/lib.rs
@@ -5,7 +5,6 @@ pub mod cloud_admin_api;
 pub mod garbage;
 pub mod metadata_stream;
 pub mod scan_metadata;
-pub mod tenant_snapshot;

 use std::env;
 use std::fmt::Display;
@@ -24,18 +23,17 @@ use aws_sdk_s3::config::{AsyncSleep, Region, SharedAsyncSleep};
 use aws_sdk_s3::{Client, Config};
 use aws_smithy_async::rt::sleep::TokioSleep;

-use camino::{Utf8Path, Utf8PathBuf};
 use clap::ValueEnum;
 use pageserver::tenant::TENANTS_SEGMENT_NAME;
 use pageserver_api::shard::TenantShardId;
 use reqwest::Url;
 use serde::{Deserialize, Serialize};
+use std::io::IsTerminal;
 use tokio::io::AsyncReadExt;
 use tracing::error;
 use tracing_appender::non_blocking::WorkerGuard;
 use tracing_subscriber::{fmt, prelude::*, EnvFilter};
-use utils::fs_ext;
-use utils::id::{TenantId, TimelineId};
+use utils::id::TimelineId;

 const MAX_RETRIES: usize = 20;
 const CLOUD_ADMIN_API_TOKEN_ENV_VAR: &str = "CLOUD_ADMIN_API_TOKEN";
@@ -149,23 +147,6 @@ impl RootTarget {
        self.tenants_root().with_sub_segment(&tenant_id.to_string())
    }

-    pub(crate) fn tenant_shards_prefix(&self, tenant_id: &TenantId) -> S3Target {
-        // Only pageserver remote storage contains tenant-shards
-        assert!(matches!(self, Self::Pageserver(_)));
-        let Self::Pageserver(root) = self else {
-            panic!();
-        };
-
-        S3Target {
-            bucket_name: root.bucket_name.clone(),
-            prefix_in_bucket: format!(
-                "{}/{TENANTS_SEGMENT_NAME}/{tenant_id}",
-                root.prefix_in_bucket
-            ),
-            delimiter: root.delimiter.clone(),
-        }
-    }
-
    pub fn timelines_root(&self, tenant_id: &TenantShardId) -> S3Target {
        match self {
            Self::Pageserver(_) => self.tenant_root(tenant_id).with_sub_segment("timelines"),
@@ -259,6 +240,7 @@ pub fn init_logging(file_name: &str) -> WorkerGuard {
        .with_ansi(false)
        .with_writer(file_writer);
    let stderr_logs = fmt::Layer::new()
+        .with_ansi(std::io::stderr().is_terminal())
        .with_target(false)
        .with_writer(std::io::stderr);
    tracing_subscriber::registry()
@@ -414,50 +396,3 @@ async fn download_object_with_retries(

    anyhow::bail!("Failed to download objects with key {key} {MAX_RETRIES} times")
 }
-
-async fn download_object_to_file(
-    s3_client: &Client,
-    bucket_name: &str,
-    key: &str,
-    version_id: Option<&str>,
-    local_path: &Utf8Path,
-) -> anyhow::Result<()> {
-    let tmp_path = Utf8PathBuf::from(format!("{local_path}.tmp"));
-    for _ in 0..MAX_RETRIES {
-        tokio::fs::remove_file(&tmp_path)
-            .await
-            .or_else(fs_ext::ignore_not_found)?;
-
-        let mut file = tokio::fs::File::create(&tmp_path)
-            .await
-            .context("Opening output file")?;
-
-        let request = s3_client.get_object().bucket(bucket_name).key(key);
-
-        let request = match version_id {
-            Some(version_id) => request.version_id(version_id),
-            None => request,
-        };
-
-        let response_stream = match request.send().await {
-            Ok(response) => response,
-            Err(e) => {
-                error!(
-                    "Failed to download object for key {key} version {}: {e:#}",
-                    version_id.unwrap_or("")
-                );
-                tokio::time::sleep(Duration::from_secs(1)).await;
-                continue;
-            }
-        };
-
-        let mut read_stream = response_stream.body.into_async_read();
-
-        tokio::io::copy(&mut read_stream, &mut file).await?;
-
-        tokio::fs::rename(&tmp_path, local_path).await?;
-        return Ok(());
-    }
-
-    anyhow::bail!("Failed to download objects with key {key} {MAX_RETRIES} times")
-}
--- a/s3_scrubber/src/main.rs
+++ b/s3_scrubber/src/main.rs
@@ -1,12 +1,9 @@
-use camino::Utf8PathBuf;
 use pageserver_api::shard::TenantShardId;
 use s3_scrubber::garbage::{find_garbage, purge_garbage, PurgeMode};
 use s3_scrubber::scan_metadata::scan_metadata;
-use s3_scrubber::tenant_snapshot::SnapshotDownloader;
 use s3_scrubber::{init_logging, BucketConfig, ConsoleConfig, NodeKind, TraversingDepth};

 use clap::{Parser, Subcommand};
-use utils::id::TenantId;

 #[derive(Parser)]
 #[command(author, version, about, long_about = None)]
@@ -41,14 +38,6 @@ enum Command {
        #[arg(long = "tenant-id", num_args = 0..)]
        tenant_ids: Vec<TenantShardId>,
    },
-    TenantSnapshot {
-        #[arg(long = "tenant-id")]
-        tenant_id: TenantId,
-        #[arg(long = "concurrency", short = 'j', default_value_t = 8)]
-        concurrency: usize,
-        #[arg(short, long)]
-        output_path: Utf8PathBuf,
-    },
 }

 #[tokio::main]
@@ -61,7 +50,6 @@ async fn main() -> anyhow::Result<()> {
        Command::ScanMetadata { .. } => "scan",
        Command::FindGarbage { .. } => "find-garbage",
        Command::PurgeGarbage { .. } => "purge-garbage",
-        Command::TenantSnapshot { .. } => "tenant-snapshot",
    };
    let _guard = init_logging(&format!(
        "{}_{}_{}_{}.log",
@@ -114,14 +102,5 @@ async fn main() -> anyhow::Result<()> {
        Command::PurgeGarbage { input_path, mode } => {
            purge_garbage(input_path, mode, !cli.delete).await
        }
-        Command::TenantSnapshot {
-            tenant_id,
-            output_path,
-            concurrency,
-        } => {
-            let downloader =
-                SnapshotDownloader::new(bucket_config, tenant_id, output_path, concurrency)?;
-            downloader.download().await
-        }
    }
 }
--- a/s3_scrubber/src/metadata_stream.rs
+++ b/s3_scrubber/src/metadata_stream.rs
@@ -5,7 +5,7 @@ use tokio_stream::Stream;

 use crate::{list_objects_with_retries, RootTarget, S3Target, TenantShardTimelineId};
 use pageserver_api::shard::TenantShardId;
-use utils::id::{TenantId, TimelineId};
+use utils::id::TimelineId;

 /// Given an S3 bucket, output a stream of TenantIds discovered via ListObjectsv2
 pub fn stream_tenants<'a>(
@@ -45,62 +45,6 @@ pub fn stream_tenants<'a>(
    }
 }

-pub async fn stream_tenant_shards<'a>(
-    s3_client: &'a Client,
-    target: &'a RootTarget,
-    tenant_id: TenantId,
-) -> anyhow::Result<impl Stream<Item = Result<TenantShardId, anyhow::Error>> + 'a> {
-    let mut tenant_shard_ids: Vec<Result<TenantShardId, anyhow::Error>> = Vec::new();
-    let mut continuation_token = None;
-    let shards_target = target.tenant_shards_prefix(&tenant_id);
-
-    loop {
-        tracing::info!("Listing in {}", shards_target.prefix_in_bucket);
-        let fetch_response =
-            list_objects_with_retries(s3_client, &shards_target, continuation_token.clone()).await;
-        let fetch_response = match fetch_response {
-            Err(e) => {
-                tenant_shard_ids.push(Err(e));
-                break;
-            }
-            Ok(r) => r,
-        };
-
-        let new_entry_ids = fetch_response
-            .common_prefixes()
-            .iter()
-            .filter_map(|prefix| prefix.prefix())
-            .filter_map(|prefix| -> Option<&str> {
-                prefix
-                    .strip_prefix(&target.tenants_root().prefix_in_bucket)?
-                    .strip_suffix('/')
-            })
-            .map(|entry_id_str| {
-                let first_part = entry_id_str.split('/').next().unwrap();
-
-                first_part
-                    .parse::<TenantShardId>()
-                    .with_context(|| format!("Incorrect entry id str: {first_part}"))
-            });
-
-        for i in new_entry_ids {
-            tenant_shard_ids.push(i);
-        }
-
-        match fetch_response.next_continuation_token {
-            Some(new_token) => continuation_token = Some(new_token),
-            None => break,
-        }
-    }
-
-    Ok(stream! {
-        for i in tenant_shard_ids {
-            let id = i?;
-            yield Ok(id);
-        }
-    })
-}
-
 /// Given a TenantShardId, output a stream of the timelines within that tenant, discovered
 /// using ListObjectsv2.  The listing is done before the stream is built, so that this
 /// function can be used to generate concurrency on a stream using buffer_unordered.
--- a/s3_scrubber/src/tenant_snapshot.rs
+++ b/s3_scrubber/src/tenant_snapshot.rs
@@ -1,293 +0,0 @@
-use std::collections::HashMap;
-use std::sync::Arc;
-
-use crate::checks::{list_timeline_blobs, BlobDataParseResult, S3TimelineBlobData};
-use crate::metadata_stream::{stream_tenant_shards, stream_tenant_timelines};
-use crate::{
-    download_object_to_file, init_remote, BucketConfig, NodeKind, RootTarget, TenantShardTimelineId,
-};
-use anyhow::Context;
-use async_stream::stream;
-use aws_sdk_s3::Client;
-use camino::Utf8PathBuf;
-use futures::{StreamExt, TryStreamExt};
-use pageserver::tenant::remote_timeline_client::index::IndexLayerMetadata;
-use pageserver::tenant::storage_layer::LayerFileName;
-use pageserver::tenant::IndexPart;
-use pageserver_api::shard::TenantShardId;
-use utils::generation::Generation;
-use utils::id::TenantId;
-
-pub struct SnapshotDownloader {
-    s3_client: Arc<Client>,
-    s3_root: RootTarget,
-    bucket_config: BucketConfig,
-    tenant_id: TenantId,
-    output_path: Utf8PathBuf,
-    concurrency: usize,
-}
-
-impl SnapshotDownloader {
-    pub fn new(
-        bucket_config: BucketConfig,
-        tenant_id: TenantId,
-        output_path: Utf8PathBuf,
-        concurrency: usize,
-    ) -> anyhow::Result<Self> {
-        let (s3_client, s3_root) = init_remote(bucket_config.clone(), NodeKind::Pageserver)?;
-        Ok(Self {
-            s3_client,
-            s3_root,
-            bucket_config,
-            tenant_id,
-            output_path,
-            concurrency,
-        })
-    }
-
-    async fn download_layer(
-        &self,
-        ttid: TenantShardTimelineId,
-        layer_name: LayerFileName,
-        layer_metadata: IndexLayerMetadata,
-    ) -> anyhow::Result<(LayerFileName, IndexLayerMetadata)> {
-        // Note this is local as in a local copy of S3 data, not local as in the pageserver's local format.  They use
-        // different layer names (remote-style has the generation suffix)
-        let local_path = self.output_path.join(format!(
-            "{}/timelines/{}/{}{}",
-            ttid.tenant_shard_id,
-            ttid.timeline_id,
-            layer_name.file_name(),
-            layer_metadata.generation.get_suffix()
-        ));
-
-        // We should only be called for layers that are owned by the input TTID
-        assert_eq!(layer_metadata.shard, ttid.tenant_shard_id.to_index());
-
-        // Assumption: we always write layer files atomically, and layer files are immutable.  Therefore if the file
-        // already exists on local disk, we assume it is fully correct and skip it.
-        if tokio::fs::try_exists(&local_path).await? {
-            tracing::debug!("{} already exists", local_path);
-            return Ok((layer_name, layer_metadata));
-        } else {
-            tracing::debug!("{} requires download...", local_path);
-
-            let timeline_root = self.s3_root.timeline_root(&ttid);
-            let remote_layer_path = format!(
-                "{}{}{}",
-                timeline_root.prefix_in_bucket,
-                layer_name.file_name(),
-                layer_metadata.generation.get_suffix()
-            );
-
-            // List versions: the object might be deleted.
-            let versions = self
-                .s3_client
-                .list_object_versions()
-                .bucket(self.bucket_config.bucket.clone())
-                .prefix(&remote_layer_path)
-                .send()
-                .await?;
-            let Some(version) = versions.versions.as_ref().and_then(|v| v.first()) else {
-                return Err(anyhow::anyhow!("No versions found for {remote_layer_path}"));
-            };
-            download_object_to_file(
-                &self.s3_client,
-                &self.bucket_config.bucket,
-                &remote_layer_path,
-                version.version_id.as_deref(),
-                &local_path,
-            )
-            .await?;
-
-            tracing::debug!("Downloaded successfully to {local_path}");
-        }
-
-        Ok((layer_name, layer_metadata))
-    }
-
-    /// Download many layers belonging to the same TTID, with some concurrency
-    async fn download_layers(
-        &self,
-        ttid: TenantShardTimelineId,
-        layers: Vec<(LayerFileName, IndexLayerMetadata)>,
-    ) -> anyhow::Result<()> {
-        let layer_count = layers.len();
-        tracing::info!("Downloading {} layers for timeline {ttid}...", layer_count);
-        let layers_stream = stream! {
-            for (layer_name, layer_metadata) in layers {
-                yield self.download_layer(ttid, layer_name, layer_metadata);
-            }
-        };
-
-        tokio::fs::create_dir_all(self.output_path.join(format!(
-            "{}/timelines/{}",
-            ttid.tenant_shard_id, ttid.timeline_id
-        )))
-        .await?;
-
-        let layer_results = layers_stream.buffered(self.concurrency);
-        let mut layer_results = std::pin::pin!(layer_results);
-
-        let mut err = None;
-        let mut download_count = 0;
-        while let Some(i) = layer_results.next().await {
-            download_count += 1;
-            match i {
-                Ok((layer_name, layer_metadata)) => {
-                    tracing::info!(
-                        "[{download_count}/{layer_count}] OK: {} bytes {ttid} {}",
-                        layer_metadata.file_size,
-                        layer_name.file_name()
-                    );
-                }
-                Err(e) => {
-                    // Warn and continue: we will download what we can
-                    tracing::warn!("Download error: {e}");
-                    err = Some(e);
-                }
-            }
-        }
-        if let Some(e) = err {
-            tracing::warn!("Some errors occurred downloading {ttid} layers, last error: {e}");
-            Err(e)
-        } else {
-            Ok(())
-        }
-    }
-
-    async fn download_timeline(
-        &self,
-        ttid: TenantShardTimelineId,
-        index_part: IndexPart,
-        index_part_generation: Generation,
-        ancestor_layers: &mut HashMap<
-            TenantShardTimelineId,
-            HashMap<LayerFileName, IndexLayerMetadata>,
-        >,
-    ) -> anyhow::Result<()> {
-        let index_bytes = serde_json::to_string(&index_part).unwrap();
-
-        let layers = index_part
-            .layer_metadata
-            .into_iter()
-            .filter_map(|(layer_name, layer_metadata)| {
-                if layer_metadata.shard.shard_count != ttid.tenant_shard_id.shard_count {
-                    // Accumulate ancestor layers for later download
-                    let ancestor_ttid = TenantShardTimelineId::new(
-                        TenantShardId {
-                            tenant_id: ttid.tenant_shard_id.tenant_id,
-                            shard_number: layer_metadata.shard.shard_number,
-                            shard_count: layer_metadata.shard.shard_count,
-                        },
-                        ttid.timeline_id,
-                    );
-                    let ancestor_ttid_layers = ancestor_layers.entry(ancestor_ttid).or_default();
-                    use std::collections::hash_map::Entry;
-                    match ancestor_ttid_layers.entry(layer_name) {
-                        Entry::Occupied(entry) => {
-                            // Descendent shards that reference a layer from an ancestor should always have matching metadata,
-                            // as their siblings, because it is read atomically during a shard split.
-                            assert_eq!(entry.get(), &layer_metadata);
-                        }
-                        Entry::Vacant(entry) => {
-                            entry.insert(layer_metadata);
-                        }
-                    }
-                    None
-                } else {
-                    Some((layer_name, layer_metadata))
-                }
-            })
-            .collect();
-
-        let download_result = self.download_layers(ttid, layers).await;
-
-        // Write index last, once all the layers it references are downloaded
-        let local_index_path = self.output_path.join(format!(
-            "{}/timelines/{}/index_part.json{}",
-            ttid.tenant_shard_id,
-            ttid.timeline_id,
-            index_part_generation.get_suffix()
-        ));
-        tokio::fs::write(&local_index_path, index_bytes)
-            .await
-            .context("writing index")?;
-
-        download_result
-    }
-
-    pub async fn download(&self) -> anyhow::Result<()> {
-        let (s3_client, target) = init_remote(self.bucket_config.clone(), NodeKind::Pageserver)?;
-
-        // Generate a stream of TenantShardId
-        let shards = stream_tenant_shards(&s3_client, &target, self.tenant_id).await?;
-        let shards: Vec<TenantShardId> = shards.try_collect().await?;
-
-        // Only read from shards that have the highest count: avoids redundantly downloading
-        // from ancestor shards.
-        let Some(shard_count) = shards.iter().map(|s| s.shard_count).max() else {
-            anyhow::bail!("No shards found");
-        };
-
-        // We will build a collection of layers in anccestor shards to download (this will only
-        // happen if this tenant has been split at some point)
-        let mut ancestor_layers: HashMap<
-            TenantShardTimelineId,
-            HashMap<LayerFileName, IndexLayerMetadata>,
-        > = Default::default();
-
-        for shard in shards.into_iter().filter(|s| s.shard_count == shard_count) {
-            // Generate a stream of TenantTimelineId
-            let timelines = stream_tenant_timelines(&s3_client, &self.s3_root, shard).await?;
-
-            // Generate a stream of S3TimelineBlobData
-            async fn load_timeline_index(
-                s3_client: &Client,
-                target: &RootTarget,
-                ttid: TenantShardTimelineId,
-            ) -> anyhow::Result<(TenantShardTimelineId, S3TimelineBlobData)> {
-                let data = list_timeline_blobs(s3_client, ttid, target).await?;
-                Ok((ttid, data))
-            }
-            let timelines = timelines.map_ok(|ttid| load_timeline_index(&s3_client, &target, ttid));
-            let mut timelines = std::pin::pin!(timelines.try_buffered(8));
-
-            while let Some(i) = timelines.next().await {
-                let (ttid, data) = i?;
-                match data.blob_data {
-                    BlobDataParseResult::Parsed {
-                        index_part,
-                        index_part_generation,
-                        s3_layers: _,
-                    } => {
-                        self.download_timeline(
-                            ttid,
-                            index_part,
-                            index_part_generation,
-                            &mut ancestor_layers,
-                        )
-                        .await
-                        .context("Downloading timeline")?;
-                    }
-                    BlobDataParseResult::Relic => {}
-                    BlobDataParseResult::Incorrect(_) => {
-                        tracing::error!("Bad metadata in timeline {ttid}");
-                    }
-                };
-            }
-        }
-
-        for (ttid, layers) in ancestor_layers.into_iter() {
-            tracing::info!(
-                "Downloading {} layers from ancvestor timeline {ttid}...",
-                layers.len()
-            );
-
-            self.download_layers(ttid, layers.into_iter().collect())
-                .await?;
-        }
-
-        Ok(())
-    }
-}
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Conrad Ludgate	7d2709f4a1	back to published versions	2024-04-22 10:28:29 +01:00
Conrad Ludgate	6e2c04bc48	custom jemalloc opts	2024-04-22 10:26:49 +01:00
Conrad Ludgate	76ae735a24	bump	2024-04-22 06:55:43 +01:00
Conrad Ludgate	7be445f627	jemalloc profiling	2024-04-22 06:48:03 +01:00