move benchmarks to another repo

## Problem
rest broker needs to respond with the correct cors headers for the api
to be usable from other domains

## Summary of changes
added a code path in rest broker to handle the OPTIONS requests

---------

Co-authored-by: Ruslan Talpa <ruslan.talpa@databricks.com>

.github/workflows/build_and_test.yml

@@ -300,7 +300,9 @@ jobs:
 
   benchmarks:
     # `!failure() && !cancelled()` is required because the workflow depends on the job that can be skipped: `deploy` in PRs
-    if: github.ref_name == 'main' || (contains(github.event.pull_request.labels.*.name, 'run-benchmarks') && !failure() && !cancelled())
+    # if: github.ref_name == 'main' || (contains(github.event.pull_request.labels.*.name, 'run-benchmarks') && !failure() && !cancelled())
+    # moved to another repo
+    if: false
     needs: [ check-permissions, build-build-tools-image, get-benchmarks-durations, deploy ]
     permissions:
       id-token: write # aws-actions/configure-aws-credentials

.gitignore

@@ -15,7 +15,6 @@ neon.iml
 /.neon
 /integration_tests/.neon
 compaction-suite-results.*
-pgxn/neon/communicator/communicator_bindings.h
 docker-compose/docker-compose-parallel.yml
 
 # Coverage

Cargo.lock

@@ -259,17 +259,6 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a8ab6b55fe97976e46f91ddbed8d147d966475dc29b2032757ba47e02376fbc3"
 
-[[package]]
-name = "atomic_enum"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "99e1aca718ea7b89985790c94aad72d77533063fe00bc497bb79a7c2dae6a661"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn 2.0.100",
-]
-
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@@ -1307,31 +1296,13 @@ dependencies = [
 name = "communicator"
 version = "0.1.0"
 dependencies = [
- "atomic_enum",
  "axum",
- "bytes",
  "cbindgen",
- "clashmap",
- "fiemap",
  "http 1.3.1",
- "itertools 0.10.5",
- "libc",
  "measured",
- "neon-shmem",
- "nix 0.30.1",
- "pageserver_api",
- "pageserver_client_grpc",
- "pageserver_page_api",
- "prometheus",
- "prost 0.13.5",
- "strum_macros",
- "thiserror 1.0.69",
  "tokio",
- "tokio-pipe",
- "tonic",
  "tracing",
  "tracing-subscriber",
- "uring-common",
  "utils",
  "workspace_hack",
 ]
@@ -1672,9 +1643,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.21"
+version = "0.8.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+checksum = "248e3bacc7dc6baa3b21e405ee045c3047101a49145e7e9eca583ab4c2ca5345"
 
 [[package]]
 name = "crossterm"
@@ -2338,15 +2309,6 @@ version = "0.2.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "28dea519a9695b9977216879a3ebfddf92f1c08c05d984f8996aecd6ecdc811d"
 
-[[package]]
-name = "fiemap"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "92e387bc8b3342ba5cd115fb566e6bf2c82562433dffcecbc2474265cf8a875a"
-dependencies = [
- "bitflags 2.8.0",
-]
-
 [[package]]
 name = "filetime"
 version = "0.2.22"
@@ -4429,16 +4391,13 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "async-trait",
- "axum",
  "bytes",
  "camino",
  "clap",
  "futures",
  "hdrhistogram",
- "http 1.3.1",
  "humantime",
  "humantime-serde",
- "metrics",
  "pageserver_api",
  "pageserver_client",
  "pageserver_client_grpc",
@@ -4528,7 +4487,6 @@ dependencies = [
  "pageserver_client",
  "pageserver_compaction",
  "pageserver_page_api",
- "peekable",
  "pem",
  "pin-project-lite",
  "postgres-protocol",
@@ -4542,7 +4500,6 @@ dependencies = [
  "pprof",
  "pq_proto",
  "procfs",
- "prost 0.13.5",
  "rand 0.9.1",
  "range-set-blaze",
  "regex",
@@ -4837,15 +4794,6 @@ dependencies = [
  "sha2",
 ]
 
-[[package]]
-name = "peekable"
-version = "0.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "225f9651e475709164f871dc2f5724956be59cb9edb055372ffeeab01ec2d20b"
-dependencies = [
- "smallvec",
-]
-
 [[package]]
 name = "pem"
 version = "3.0.3"
@@ -7698,16 +7646,6 @@ dependencies = [
  "syn 2.0.100",
 ]
 
-[[package]]
-name = "tokio-pipe"
-version = "0.2.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f213a84bffbd61b8fa0ba8a044b4bbe35d471d0b518867181e82bd5c15542784"
-dependencies = [
- "libc",
- "tokio",
-]
-
 [[package]]
 name = "tokio-postgres"
 version = "0.7.10"
@@ -9075,8 +9013,8 @@ dependencies = [
  "clap",
  "clap_builder",
  "const-oid",
- "criterion",
  "crossbeam-epoch",
+ "crossbeam-utils",
  "crypto-bigint 0.5.5",
  "der 0.7.8",
  "deranged",
@@ -9119,6 +9057,7 @@ dependencies = [
  "num-iter",
  "num-rational",
  "num-traits",
+ "once_cell",
  "p256 0.13.2",
  "parquet",
  "portable-atomic",

Cargo.toml

@@ -93,7 +93,6 @@ clap = { version = "4.0", features = ["derive", "env"] }
 clashmap = { version = "1.0", features = ["raw-api"] }
 comfy-table = "7.1"
 const_format = "0.2"
-crossbeam-utils = "0.8.21"
 crc32c = "0.6"
 diatomic-waker = { version = "0.2.3" }
 either = "1.8"
@@ -153,7 +152,6 @@ parquet = { version = "53", default-features = false, features = ["zstd"] }
 parquet_derive = "53"
 pbkdf2 = { version = "0.12.1", features = ["simple", "std"] }
 pem = "3.0.3"
-peekable = "0.3.0"
 pin-project-lite = "0.2"
 pprof = { version = "0.14", features = ["criterion", "flamegraph", "frame-pointer", "prost-codec"] }
 procfs = "0.16"
@@ -192,7 +190,6 @@ smallvec = "1.11"
 smol_str = { version = "0.2.0", features = ["serde"] }
 socket2 = "0.5"
 spki = "0.7.3"
-spin = "0.9.8"
 strum = "0.26"
 strum_macros = "0.26"
 "subtle"  = "2.5.0"
@@ -204,6 +201,7 @@ thiserror = "1.0"
 tikv-jemallocator = { version = "0.6", features = ["profiling", "stats", "unprefixed_malloc_on_supported_platforms"] }
 tikv-jemalloc-ctl = { version = "0.6", features = ["stats"] }
 tokio = { version = "1.43.1", features = ["macros"] }
+tokio-epoll-uring = { git = "https://github.com/neondatabase/tokio-epoll-uring.git" , branch = "main" }
 tokio-io-timeout = "1.2.0"
 tokio-postgres-rustls = "0.12.0"
 tokio-rustls = { version = "0.26.0", default-features = false, features = ["tls12", "ring"]}
@@ -244,9 +242,6 @@ zeroize = "1.8"
 env_logger = "0.11"
 log = "0.4"
 
-tokio-epoll-uring = { git = "https://github.com/neondatabase/tokio-epoll-uring.git" , branch = "main" }
-uring-common = { git = "https://github.com/neondatabase/tokio-epoll-uring.git" , branch = "main" }
-
 ## Libraries from neondatabase/ git forks, ideally with changes to be upstreamed
 postgres = { git = "https://github.com/neondatabase/rust-postgres.git", branch = "neon" }
 postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", branch = "neon" }

compute_tools/src/compute.rs

@@ -2780,7 +2780,7 @@ LIMIT 100",
                 // 4. We start again and try to prewarm with the state from 2. instead of the previous complete state
                 if matches!(
                     prewarm_state,
-                    LfcPrewarmState::Completed
+                    LfcPrewarmState::Completed { .. }
                         | LfcPrewarmState::NotPrewarmed
                         | LfcPrewarmState::Skipped
                 ) {

compute_tools/src/compute_prewarm.rs

@@ -7,19 +7,11 @@ use http::StatusCode;
 use reqwest::Client;
 use std::mem::replace;
 use std::sync::Arc;
+use std::time::Instant;
 use tokio::{io::AsyncReadExt, select, spawn};
 use tokio_util::sync::CancellationToken;
 use tracing::{error, info};
 
-#[derive(serde::Serialize, Default)]
-pub struct LfcPrewarmStateWithProgress {
-    #[serde(flatten)]
-    base: LfcPrewarmState,
-    total: i32,
-    prewarmed: i32,
-    skipped: i32,
-}
-
 /// A pair of url and a token to query endpoint storage for LFC prewarm-related tasks
 struct EndpointStoragePair {
     url: String,
@@ -28,7 +20,7 @@ struct EndpointStoragePair {
 
 const KEY: &str = "lfc_state";
 impl EndpointStoragePair {
-    /// endpoint_id is set to None while prewarming from other endpoint, see replica promotion
+    /// endpoint_id is set to None while prewarming from other endpoint, see compute_promote.rs
     /// If not None, takes precedence over pspec.spec.endpoint_id
     fn from_spec_and_endpoint(
         pspec: &crate::compute::ParsedSpec,
@@ -54,36 +46,8 @@ impl EndpointStoragePair {
 }
 
 impl ComputeNode {
-    // If prewarm failed, we want to get overall number of segments as well as done ones.
-    // However, this function should be reliable even if querying postgres failed.
-    pub async fn lfc_prewarm_state(&self) -> LfcPrewarmStateWithProgress {
-        info!("requesting LFC prewarm state from postgres");
-        let mut state = LfcPrewarmStateWithProgress::default();
-        {
-            state.base = self.state.lock().unwrap().lfc_prewarm_state.clone();
-        }
-
-        let client = match ComputeNode::get_maintenance_client(&self.tokio_conn_conf).await {
-            Ok(client) => client,
-            Err(err) => {
-                error!(%err, "connecting to postgres");
-                return state;
-            }
-        };
-        let row = match client
-            .query_one("select * from neon.get_prewarm_info()", &[])
-            .await
-        {
-            Ok(row) => row,
-            Err(err) => {
-                error!(%err, "querying LFC prewarm status");
-                return state;
-            }
-        };
-        state.total = row.try_get(0).unwrap_or_default();
-        state.prewarmed = row.try_get(1).unwrap_or_default();
-        state.skipped = row.try_get(2).unwrap_or_default();
-        state
+    pub async fn lfc_prewarm_state(&self) -> LfcPrewarmState {
+        self.state.lock().unwrap().lfc_prewarm_state.clone()
     }
 
     pub fn lfc_offload_state(&self) -> LfcOffloadState {
@@ -133,7 +97,6 @@ impl ComputeNode {
     }
 
     /// Request LFC state from endpoint storage and load corresponding pages into Postgres.
-    /// Returns a result with `false` if the LFC state is not found in endpoint storage.
     async fn prewarm_impl(
         &self,
         from_endpoint: Option<String>,
@@ -148,6 +111,7 @@ impl ComputeNode {
         fail::fail_point!("compute-prewarm", |_| bail!("compute-prewarm failpoint"));
 
         info!(%url, "requesting LFC state from endpoint storage");
+        let mut now = Instant::now();
         let request = Client::new().get(&url).bearer_auth(storage_token);
         let response = select! {
             _ = token.cancelled() => return Ok(LfcPrewarmState::Cancelled),
@@ -160,6 +124,8 @@ impl ComputeNode {
             StatusCode::NOT_FOUND => return Ok(LfcPrewarmState::Skipped),
             status => bail!("{status} querying endpoint storage"),
         }
+        let state_download_time_ms = now.elapsed().as_millis() as u32;
+        now = Instant::now();
 
         let mut uncompressed = Vec::new();
         let lfc_state = select! {
@@ -174,6 +140,8 @@ impl ComputeNode {
             read = decoder.read_to_end(&mut uncompressed) => read
         }
         .context("decoding LFC state")?;
+        let uncompress_time_ms = now.elapsed().as_millis() as u32;
+        now = Instant::now();
 
         let uncompressed_len = uncompressed.len();
         info!(%url, "downloaded LFC state, uncompressed size {uncompressed_len}");
@@ -196,15 +164,34 @@ impl ComputeNode {
         }
         .context("loading LFC state into postgres")
         .map(|_| ())?;
+        let prewarm_time_ms = now.elapsed().as_millis() as u32;
 
-        Ok(LfcPrewarmState::Completed)
+        let row = client
+            .query_one("select * from neon.get_prewarm_info()", &[])
+            .await
+            .context("querying prewarm info")?;
+        let total = row.try_get(0).unwrap_or_default();
+        let prewarmed = row.try_get(1).unwrap_or_default();
+        let skipped = row.try_get(2).unwrap_or_default();
+
+        Ok(LfcPrewarmState::Completed {
+            total,
+            prewarmed,
+            skipped,
+            state_download_time_ms,
+            uncompress_time_ms,
+            prewarm_time_ms,
+        })
     }
 
     /// If offload request is ongoing, return false, true otherwise
     pub fn offload_lfc(self: &Arc<Self>) -> bool {
         {
             let state = &mut self.state.lock().unwrap().lfc_offload_state;
-            if replace(state, LfcOffloadState::Offloading) == LfcOffloadState::Offloading {
+            if matches!(
+                replace(state, LfcOffloadState::Offloading),
+                LfcOffloadState::Offloading
+            ) {
                 return false;
             }
         }
@@ -216,7 +203,10 @@ impl ComputeNode {
     pub async fn offload_lfc_async(self: &Arc<Self>) {
         {
             let state = &mut self.state.lock().unwrap().lfc_offload_state;
-            if replace(state, LfcOffloadState::Offloading) == LfcOffloadState::Offloading {
+            if matches!(
+                replace(state, LfcOffloadState::Offloading),
+                LfcOffloadState::Offloading
+            ) {
                 return;
             }
         }
@@ -234,7 +224,6 @@ impl ComputeNode {
                 LfcOffloadState::Failed { error }
             }
         };
-
         self.state.lock().unwrap().lfc_offload_state = state;
     }
 
@@ -242,6 +231,7 @@ impl ComputeNode {
         let EndpointStoragePair { url, token } = self.endpoint_storage_pair(None)?;
         info!(%url, "requesting LFC state from Postgres");
 
+        let mut now = Instant::now();
         let row = ComputeNode::get_maintenance_client(&self.tokio_conn_conf)
             .await
             .context("connecting to postgres")?
@@ -255,25 +245,36 @@ impl ComputeNode {
             info!(%url, "empty LFC state, not exporting");
             return Ok(LfcOffloadState::Skipped);
         };
+        let state_query_time_ms = now.elapsed().as_millis() as u32;
+        now = Instant::now();
 
         let mut compressed = Vec::new();
         ZstdEncoder::new(state)
             .read_to_end(&mut compressed)
             .await
             .context("compressing LFC state")?;
+        let compress_time_ms = now.elapsed().as_millis() as u32;
+        now = Instant::now();
 
         let compressed_len = compressed.len();
-        info!(%url, "downloaded LFC state, compressed size {compressed_len}, writing to endpoint storage");
+        info!(%url, "downloaded LFC state, compressed size {compressed_len}");
 
         let request = Client::new().put(url).bearer_auth(token).body(compressed);
-        match request.send().await {
-            Ok(res) if res.status() == StatusCode::OK => Ok(LfcOffloadState::Completed),
-            Ok(res) => bail!(
-                "Request to endpoint storage failed with status: {}",
-                res.status()
-            ),
-            Err(err) => Err(err).context("writing to endpoint storage"),
+        let response = request
+            .send()
+            .await
+            .context("writing to endpoint storage")?;
+        let state_upload_time_ms = now.elapsed().as_millis() as u32;
+        let status = response.status();
+        if status != StatusCode::OK {
+            bail!("request to endpoint storage failed: {status}");
         }
+
+        Ok(LfcOffloadState::Completed {
+            compress_time_ms,
+            state_query_time_ms,
+            state_upload_time_ms,
+        })
     }
 
     pub fn cancel_prewarm(self: &Arc<Self>) {

compute_tools/src/compute_promote.rs

@@ -1,32 +1,24 @@
 use crate::compute::ComputeNode;
-use anyhow::{Context, Result, bail};
+use anyhow::{Context, bail};
 use compute_api::responses::{LfcPrewarmState, PromoteConfig, PromoteState};
-use compute_api::spec::ComputeMode;
-use itertools::Itertools;
-use std::collections::HashMap;
-use std::{sync::Arc, time::Duration};
-use tokio::time::sleep;
+use std::time::Instant;
 use tracing::info;
-use utils::lsn::Lsn;
 
 impl ComputeNode {
-    /// Returns only when promote fails or succeeds. If a network error occurs
-    /// and http client disconnects, this does not stop promotion, and subsequent
-    /// calls block until promote finishes.
+    /// Returns only when promote fails or succeeds. If http client calling this function
+    /// disconnects, this does not stop promotion, and subsequent calls block until promote finishes.
     /// Called by control plane on secondary after primary endpoint is terminated
     /// Has a failpoint "compute-promotion"
-    pub async fn promote(self: &Arc<Self>, cfg: PromoteConfig) -> PromoteState {
-        let cloned = self.clone();
-        let promote_fn = async move || {
-            let Err(err) = cloned.promote_impl(cfg).await else {
-                return PromoteState::Completed;
-            };
-            tracing::error!(%err, "promoting");
-            PromoteState::Failed {
-                error: format!("{err:#}"),
+    pub async fn promote(self: &std::sync::Arc<Self>, cfg: PromoteConfig) -> PromoteState {
+        let this = self.clone();
+        let promote_fn = async move || match this.promote_impl(cfg).await {
+            Ok(state) => state,
+            Err(err) => {
+                tracing::error!(%err, "promoting replica");
+                let error = format!("{err:#}");
+                PromoteState::Failed { error }
             }
         };
-
         let start_promotion = || {
             let (tx, rx) = tokio::sync::watch::channel(PromoteState::NotPromoted);
             tokio::spawn(async move { tx.send(promote_fn().await) });
@@ -34,36 +26,31 @@ impl ComputeNode {
         };
 
         let mut task;
-        // self.state is unlocked after block ends so we lock it in promote_impl
-        // and task.changed() is reached
+        // promote_impl locks self.state so we need to unlock it before calling task.changed()
         {
-            task = self
-                .state
-                .lock()
-                .unwrap()
-                .promote_state
-                .get_or_insert_with(start_promotion)
-                .clone()
+            let promote_state = &mut self.state.lock().unwrap().promote_state;
+            task = promote_state.get_or_insert_with(start_promotion).clone()
+        }
+        if task.changed().await.is_err() {
+            let error = "promote sender dropped".to_string();
+            return PromoteState::Failed { error };
         }
-        task.changed().await.expect("promote sender dropped");
         task.borrow().clone()
     }
 
-    async fn promote_impl(&self, mut cfg: PromoteConfig) -> Result<()> {
+    async fn promote_impl(&self, cfg: PromoteConfig) -> anyhow::Result<PromoteState> {
         {
             let state = self.state.lock().unwrap();
             let mode = &state.pspec.as_ref().unwrap().spec.mode;
-            if *mode != ComputeMode::Replica {
-                bail!("{} is not replica", mode.to_type_str());
+            if *mode != compute_api::spec::ComputeMode::Replica {
+                bail!("compute mode \"{}\" is not replica", mode.to_type_str());
             }
-
-            // we don't need to query Postgres so not self.lfc_prewarm_state()
             match &state.lfc_prewarm_state {
-                LfcPrewarmState::NotPrewarmed | LfcPrewarmState::Prewarming => {
-                    bail!("prewarm not requested or pending")
+                status @ (LfcPrewarmState::NotPrewarmed | LfcPrewarmState::Prewarming) => {
+                    bail!("compute {status}")
                 }
                 LfcPrewarmState::Failed { error } => {
-                    tracing::warn!(%error, "replica prewarm failed")
+                    tracing::warn!(%error, "compute prewarm failed")
                 }
                 _ => {}
             }
@@ -72,9 +59,10 @@ impl ComputeNode {
         let client = ComputeNode::get_maintenance_client(&self.tokio_conn_conf)
             .await
             .context("connecting to postgres")?;
+        let mut now = Instant::now();
 
         let primary_lsn = cfg.wal_flush_lsn;
-        let mut last_wal_replay_lsn: Lsn = Lsn::INVALID;
+        let mut standby_lsn = utils::lsn::Lsn::INVALID;
         const RETRIES: i32 = 20;
         for i in 0..=RETRIES {
             let row = client
@@ -82,16 +70,18 @@ impl ComputeNode {
                 .await
                 .context("getting last replay lsn")?;
             let lsn: u64 = row.get::<usize, postgres_types::PgLsn>(0).into();
-            last_wal_replay_lsn = lsn.into();
-            if last_wal_replay_lsn >= primary_lsn {
+            standby_lsn = lsn.into();
+            if standby_lsn >= primary_lsn {
                 break;
             }
-            info!("Try {i}, replica lsn {last_wal_replay_lsn}, primary lsn {primary_lsn}");
-            sleep(Duration::from_secs(1)).await;
+            info!(%standby_lsn, %primary_lsn, "catching up, try {i}");
+            tokio::time::sleep(std::time::Duration::from_secs(1)).await;
         }
-        if last_wal_replay_lsn < primary_lsn {
+        if standby_lsn < primary_lsn {
             bail!("didn't catch up with primary in {RETRIES} retries");
         }
+        let lsn_wait_time_ms = now.elapsed().as_millis() as u32;
+        now = Instant::now();
 
         // using $1 doesn't work with ALTER SYSTEM SET
         let safekeepers_sql = format!(
@@ -102,27 +92,33 @@ impl ComputeNode {
             .query(&safekeepers_sql, &[])
             .await
             .context("setting safekeepers")?;
+        client
+            .query(
+                "ALTER SYSTEM SET synchronous_standby_names=walproposer",
+                &[],
+            )
+            .await
+            .context("setting synchronous_standby_names")?;
         client
             .query("SELECT pg_catalog.pg_reload_conf()", &[])
             .await
             .context("reloading postgres config")?;
 
         #[cfg(feature = "testing")]
-        fail::fail_point!("compute-promotion", |_| {
-            bail!("promotion configured to fail because of a failpoint")
-        });
+        fail::fail_point!("compute-promotion", |_| bail!(
+            "compute-promotion failpoint"
+        ));
 
         let row = client
             .query_one("SELECT * FROM pg_catalog.pg_promote()", &[])
             .await
             .context("pg_promote")?;
         if !row.get::<usize, bool>(0) {
-            bail!("pg_promote() returned false");
+            bail!("pg_promote() failed");
         }
+        let pg_promote_time_ms = now.elapsed().as_millis() as u32;
+        let now = Instant::now();
 
-        let client = ComputeNode::get_maintenance_client(&self.tokio_conn_conf)
-            .await
-            .context("connecting to postgres")?;
         let row = client
             .query_one("SHOW transaction_read_only", &[])
             .await
@@ -131,36 +127,47 @@ impl ComputeNode {
             bail!("replica in read only mode after promotion");
         }
 
+        // Already checked validity in http handler
+        #[allow(unused_mut)]
+        let mut new_pspec = crate::compute::ParsedSpec::try_from(cfg.spec).expect("invalid spec");
         {
             let mut state = self.state.lock().unwrap();
-            let spec = &mut state.pspec.as_mut().unwrap().spec;
-            spec.mode = ComputeMode::Primary;
-            let new_conf = cfg.spec.cluster.postgresql_conf.as_mut().unwrap();
-            let existing_conf = spec.cluster.postgresql_conf.as_ref().unwrap();
-            Self::merge_spec(new_conf, existing_conf);
+
+            // Local setup has different ports for pg process (port=) for primary and secondary.
+            // Primary is stopped so we need secondary's "port" value
+            #[cfg(feature = "testing")]
+            {
+                let old_spec = &state.pspec.as_ref().unwrap().spec;
+                let Some(old_conf) = old_spec.cluster.postgresql_conf.as_ref() else {
+                    bail!("pspec.spec.cluster.postgresql_conf missing for endpoint");
+                };
+                let set: std::collections::HashMap<&str, &str> = old_conf
+                    .split_terminator('\n')
+                    .map(|e| e.split_once("=").expect("invalid item"))
+                    .collect();
+
+                let Some(new_conf) = new_pspec.spec.cluster.postgresql_conf.as_mut() else {
+                    bail!("pspec.spec.cluster.postgresql_conf missing for supplied config");
+                };
+                new_conf.push_str(&format!("port={}\n", set["port"]));
+            }
+
+            tracing::debug!("applied spec: {:#?}", new_pspec.spec);
+            if self.params.lakebase_mode {
+                ComputeNode::set_spec(&self.params, &mut state, new_pspec);
+            } else {
+                state.pspec = Some(new_pspec);
+            }
         }
+
         info!("applied new spec, reconfiguring as primary");
-        self.reconfigure()
-    }
+        self.reconfigure()?;
+        let reconfigure_time_ms = now.elapsed().as_millis() as u32;
 
-    /// Merge old and new Postgres conf specs to apply on secondary.
-    /// Change new spec's port and safekeepers since they are supplied
-    /// differenly
-    fn merge_spec(new_conf: &mut String, existing_conf: &str) {
-        let mut new_conf_set: HashMap<&str, &str> = new_conf
-            .split_terminator('\n')
-            .map(|e| e.split_once("=").expect("invalid item"))
-            .collect();
-        new_conf_set.remove("neon.safekeepers");
-
-        let existing_conf_set: HashMap<&str, &str> = existing_conf
-            .split_terminator('\n')
-            .map(|e| e.split_once("=").expect("invalid item"))
-            .collect();
-        new_conf_set.insert("port", existing_conf_set["port"]);
-        *new_conf = new_conf_set
-            .iter()
-            .map(|(k, v)| format!("{k}={v}"))
-            .join("\n");
+        Ok(PromoteState::Completed {
+            lsn_wait_time_ms,
+            pg_promote_time_ms,
+            reconfigure_time_ms,
+        })
     }
 }

compute_tools/src/config.rs

@@ -8,7 +8,7 @@ use std::path::Path;
 
 use compute_api::responses::TlsConfig;
 use compute_api::spec::{
-    ComputeAudit, ComputeMode, ComputeSpec, DatabricksSettings, GenericOption, PageserverProtocol,
+    ComputeAudit, ComputeMode, ComputeSpec, DatabricksSettings, GenericOption,
 };
 
 use crate::compute::ComputeNodeParams;
@@ -69,15 +69,6 @@ pub fn write_postgres_conf(
     writeln!(file, "# Neon storage settings")?;
     writeln!(file)?;
     if let Some(conninfo) = &spec.pageserver_connection_info {
-        match conninfo.prefer_protocol {
-            PageserverProtocol::Libpq => {
-                writeln!(file, "neon.use_communicator_worker=false")?;
-            }
-            PageserverProtocol::Grpc => {
-                writeln!(file, "neon.use_communicator_worker=true")?;
-            }
-        }
-
         // Stripe size GUC should be defined prior to connection string
         if let Some(stripe_size) = conninfo.stripe_size {
             writeln!(
@@ -88,7 +79,6 @@ pub fn write_postgres_conf(
         }
 
         let mut libpq_urls: Option<Vec<String>> = Some(Vec::new());
-        let mut grpc_urls: Option<Vec<String>> = Some(Vec::new());
         let num_shards = if conninfo.shard_count.0 == 0 {
             1 // unsharded, treat it as a single shard
         } else {
@@ -121,14 +111,6 @@ pub fn write_postgres_conf(
             } else {
                 libpq_urls = None
             }
-            // Similarly for gRPC URLs
-            if let Some(url) = &first_pageserver.grpc_url {
-                if let Some(ref mut urls) = grpc_urls {
-                    urls.push(url.clone());
-                }
-            } else {
-                grpc_urls = None
-            }
         }
         if let Some(libpq_urls) = libpq_urls {
             writeln!(
@@ -143,22 +125,7 @@ pub fn write_postgres_conf(
         } else {
             writeln!(file, "# no neon.pageserver_connstring")?;
         }
-        if let Some(grpc_urls) = grpc_urls {
-            writeln!(
-                file,
-                "# derived from compute spec's pageserver_conninfo field"
-            )?;
-            writeln!(
-                file,
-                "neon.pageserver_grpc_urls={}",
-                escape_conf_value(&grpc_urls.join(","))
-            )?;
-        } else {
-            writeln!(file, "# no neon.pageserver_grpc_urls")?;
-        }
     } else {
-        writeln!(file, "neon.use_communicator_worker=false")?;
-
         // Stripe size GUC should be defined prior to connection string
         if let Some(stripe_size) = spec.shard_stripe_size {
             writeln!(file, "# from compute spec's shard_stripe_size field")?;

compute_tools/src/http/openapi_spec.yaml

@@ -617,9 +617,6 @@ components:
       type: object
       required:
         - status
-        - total
-        - prewarmed
-        - skipped
       properties:
         status:
           description: LFC prewarm status
@@ -637,6 +634,15 @@ components:
         skipped:
           description: Pages processed but not prewarmed
           type: integer
+        state_download_time_ms:
+          description: Time it takes to download LFC state to compute
+          type: integer
+        uncompress_time_ms:
+          description: Time it takes to uncompress LFC state
+          type: integer
+        prewarm_time_ms:
+          description: Time it takes to prewarm LFC state in Postgres
+          type: integer
 
     LfcOffloadState:
       type: object
@@ -650,6 +656,16 @@ components:
         error:
           description: LFC offload error, if any
           type: string
+        state_query_time_ms:
+          description: Time it takes to get LFC state from Postgres
+          type: integer
+        compress_time_ms:
+          description: Time it takes to compress LFC state
+          type: integer
+        state_upload_time_ms:
+          description: Time it takes to upload LFC state to endpoint storage
+          type: integer
+
 
     PromoteState:
       type: object
@@ -663,6 +679,15 @@ components:
         error:
           description: Promote error, if any
           type: string
+        lsn_wait_time_ms:
+          description: Time it takes for secondary to catch up with primary WAL flush LSN
+          type: integer
+        pg_promote_time_ms:
+          description: Time it takes to call pg_promote on secondary
+          type: integer
+        reconfigure_time_ms:
+          description: Time it takes to reconfigure promoted secondary
+          type: integer
 
     SetRoleGrantsRequest:
       type: object

compute_tools/src/http/routes/lfc.rs

@@ -1,12 +1,11 @@
-use crate::compute_prewarm::LfcPrewarmStateWithProgress;
 use crate::http::JsonResponse;
 use axum::response::{IntoResponse, Response};
 use axum::{Json, http::StatusCode};
 use axum_extra::extract::OptionalQuery;
-use compute_api::responses::LfcOffloadState;
+use compute_api::responses::{LfcOffloadState, LfcPrewarmState};
 type Compute = axum::extract::State<std::sync::Arc<crate::compute::ComputeNode>>;
 
-pub(in crate::http) async fn prewarm_state(compute: Compute) -> Json<LfcPrewarmStateWithProgress> {
+pub(in crate::http) async fn prewarm_state(compute: Compute) -> Json<LfcPrewarmState> {
     Json(compute.lfc_prewarm_state().await)
 }
 

compute_tools/src/http/routes/promote.rs

@@ -1,11 +1,22 @@
 use crate::http::JsonResponse;
 use axum::extract::Json;
+use compute_api::responses::PromoteConfig;
 use http::StatusCode;
 
 pub(in crate::http) async fn promote(
     compute: axum::extract::State<std::sync::Arc<crate::compute::ComputeNode>>,
-    Json(cfg): Json<compute_api::responses::PromoteConfig>,
+    Json(cfg): Json<PromoteConfig>,
 ) -> axum::response::Response {
+    // Return early at the cost of extra parsing spec
+    let pspec = match crate::compute::ParsedSpec::try_from(cfg.spec) {
+        Ok(p) => p,
+        Err(e) => return JsonResponse::error(StatusCode::BAD_REQUEST, e),
+    };
+
+    let cfg = PromoteConfig {
+        spec: pspec.spec,
+        wal_flush_lsn: cfg.wal_flush_lsn,
+    };
     let state = compute.promote(cfg).await;
     if let compute_api::responses::PromoteState::Failed { error: _ } = state {
         return JsonResponse::create_response(StatusCode::INTERNAL_SERVER_ERROR, state);

compute_tools/src/lsn_lease.rs

@@ -28,10 +28,7 @@ pub fn launch_lsn_lease_bg_task_for_static(compute: &Arc<ComputeNode>) {
     let compute = compute.clone();
 
     let span = tracing::info_span!("lsn_lease_bg_task", %tenant_id, %timeline_id, %lsn);
-
-    let runtime = tokio::runtime::Handle::current();
     thread::spawn(move || {
-        let _rt_guard = runtime.enter();
         let _entered = span.entered();
         if let Err(e) = lsn_lease_bg_task(compute, tenant_id, timeline_id, lsn) {
             // TODO: might need stronger error feedback than logging an warning.

control_plane/storcon_cli/src/main.rs

@@ -303,6 +303,13 @@ enum Command {
         #[arg(long, required = true, value_delimiter = ',')]
         new_sk_set: Vec<NodeId>,
     },
+    /// Abort ongoing safekeeper migration.
+    TimelineSafekeeperMigrateAbort {
+        #[arg(long)]
+        tenant_id: TenantId,
+        #[arg(long)]
+        timeline_id: TimelineId,
+    },
 }
 
 #[derive(Parser)]
@@ -1396,6 +1403,17 @@ async fn main() -> anyhow::Result<()> {
                 )
                 .await?;
         }
+        Command::TimelineSafekeeperMigrateAbort {
+            tenant_id,
+            timeline_id,
+        } => {
+            let path =
+                format!("v1/tenant/{tenant_id}/timeline/{timeline_id}/safekeeper_migrate_abort");
+
+            storcon_client
+                .dispatch::<(), ()>(Method::POST, path, None)
+                .await?;
+        }
     }
 
     Ok(())

docker-compose/compute_wrapper/var/db/postgres/configs/config.json

@@ -120,11 +120,6 @@
                     "value": "host=pageserver port=6400",
                     "vartype": "string"
                 },
-                {
-                    "name": "neon.pageserver_grpc_urls",
-                    "value": "grpc://pageserver:6401/",
-                    "vartype": "string"
-                },
                 {
                     "name": "max_replication_write_lag",
                     "value": "500MB",

docker-compose/pageserver_config/pageserver.toml

@@ -1,7 +1,6 @@
 broker_endpoint='http://storage_broker:50051'
 pg_distrib_dir='/usr/local/'
 listen_pg_addr='0.0.0.0:6400'
-listen_grpc_addr='0.0.0.0:6401'
 listen_http_addr='0.0.0.0:9898'
 remote_storage={ endpoint='http://minio:9000', bucket_name='neon', bucket_region='eu-north-1', prefix_in_bucket='/pageserver' }
 control_plane_api='http://0.0.0.0:6666' # No storage controller in docker compose, specify a junk address

libs/compute_api/src/responses.rs

@@ -1,10 +1,9 @@
 //! Structs representing the JSON formats used in the compute_ctl's HTTP API.
 
-use std::fmt::Display;
-
 use chrono::{DateTime, Utc};
 use jsonwebtoken::jwk::JwkSet;
 use serde::{Deserialize, Serialize, Serializer};
+use std::fmt::Display;
 
 use crate::privilege::Privilege;
 use crate::spec::{ComputeSpec, Database, ExtVersion, PgIdent, Role};
@@ -49,7 +48,7 @@ pub struct ExtensionInstallResponse {
 /// Status of the LFC prewarm process. The same state machine is reused for
 /// both autoprewarm (prewarm after compute/Postgres start using the previously
 /// stored LFC state) and explicit prewarming via API.
-#[derive(Serialize, Default, Debug, Clone, PartialEq)]
+#[derive(Serialize, Default, Debug, Clone)]
 #[serde(tag = "status", rename_all = "snake_case")]
 pub enum LfcPrewarmState {
     /// Default value when compute boots up.
@@ -59,7 +58,14 @@ pub enum LfcPrewarmState {
     Prewarming,
     /// We found requested LFC state in the endpoint storage and
     /// completed prewarming successfully.
-    Completed,
+    Completed {
+        total: i32,
+        prewarmed: i32,
+        skipped: i32,
+        state_download_time_ms: u32,
+        uncompress_time_ms: u32,
+        prewarm_time_ms: u32,
+    },
     /// Unexpected error happened during prewarming. Note, `Not Found 404`
     /// response from the endpoint storage is explicitly excluded here
     /// because it can normally happen on the first compute start,
@@ -84,7 +90,7 @@ impl Display for LfcPrewarmState {
         match self {
             LfcPrewarmState::NotPrewarmed => f.write_str("NotPrewarmed"),
             LfcPrewarmState::Prewarming => f.write_str("Prewarming"),
-            LfcPrewarmState::Completed => f.write_str("Completed"),
+            LfcPrewarmState::Completed { .. } => f.write_str("Completed"),
             LfcPrewarmState::Skipped => f.write_str("Skipped"),
             LfcPrewarmState::Failed { error } => write!(f, "Error({error})"),
             LfcPrewarmState::Cancelled => f.write_str("Cancelled"),
@@ -92,26 +98,36 @@ impl Display for LfcPrewarmState {
     }
 }
 
-#[derive(Serialize, Default, Debug, Clone, PartialEq)]
+#[derive(Serialize, Default, Debug, Clone)]
 #[serde(tag = "status", rename_all = "snake_case")]
 pub enum LfcOffloadState {
     #[default]
     NotOffloaded,
     Offloading,
-    Completed,
+    Completed {
+        state_query_time_ms: u32,
+        compress_time_ms: u32,
+        state_upload_time_ms: u32,
+    },
     Failed {
         error: String,
     },
+    /// LFC state was empty so it wasn't offloaded
     Skipped,
 }
 
-#[derive(Serialize, Debug, Clone, PartialEq)]
+#[derive(Serialize, Debug, Clone)]
 #[serde(tag = "status", rename_all = "snake_case")]
-/// Response of /promote
 pub enum PromoteState {
     NotPromoted,
-    Completed,
-    Failed { error: String },
+    Completed {
+        lsn_wait_time_ms: u32,
+        pg_promote_time_ms: u32,
+        reconfigure_time_ms: u32,
+    },
+    Failed {
+        error: String,
+    },
 }
 
 #[derive(Deserialize, Default, Debug)]

libs/neon-shmem/Cargo.toml

@@ -16,5 +16,5 @@ rustc-hash.workspace = true
 tempfile = "3.14.0"
 
 [dev-dependencies]
-rand = "0.9"
-rand_distr = "0.5.1"
+rand.workspace = true
+rand_distr = "0.5.1"

libs/neon-shmem/benches/hmap_resize.rs

@@ -1,330 +0,0 @@
-use criterion::{BatchSize, BenchmarkId, Criterion, criterion_group, criterion_main};
-use neon_shmem::hash::HashMapAccess;
-use neon_shmem::hash::HashMapInit;
-use neon_shmem::hash::entry::Entry;
-use rand::distr::{Distribution, StandardUniform};
-use rand::prelude::*;
-use std::default::Default;
-use std::hash::BuildHasher;
-
-// Taken from bindings to C code
-
-#[derive(Clone, Debug, Hash, Eq, PartialEq)]
-#[repr(C)]
-pub struct FileCacheKey {
-    pub _spc_id: u32,
-    pub _db_id: u32,
-    pub _rel_number: u32,
-    pub _fork_num: u32,
-    pub _block_num: u32,
-}
-
-impl Distribution<FileCacheKey> for StandardUniform {
-    // questionable, but doesn't need to be good randomness
-    fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> FileCacheKey {
-        FileCacheKey {
-            _spc_id: rng.random(),
-            _db_id: rng.random(),
-            _rel_number: rng.random(),
-            _fork_num: rng.random(),
-            _block_num: rng.random(),
-        }
-    }
-}
-
-#[derive(Clone, Debug)]
-#[repr(C)]
-pub struct FileCacheEntry {
-    pub _offset: u32,
-    pub _access_count: u32,
-    pub _prev: *mut FileCacheEntry,
-    pub _next: *mut FileCacheEntry,
-    pub _state: [u32; 8],
-}
-
-impl FileCacheEntry {
-    fn dummy() -> Self {
-        Self {
-            _offset: 0,
-            _access_count: 0,
-            _prev: std::ptr::null_mut(),
-            _next: std::ptr::null_mut(),
-            _state: [0; 8],
-        }
-    }
-}
-
-// Utilities for applying operations.
-
-#[derive(Clone, Debug)]
-struct TestOp<K, V>(K, Option<V>);
-
-fn apply_op<K: Clone + std::hash::Hash + Eq, V, S: std::hash::BuildHasher>(
-    op: TestOp<K, V>,
-    map: &mut HashMapAccess<K, V, S>,
-) {
-    let entry = map.entry(op.0);
-
-    match op.1 {
-        Some(new) => match entry {
-            Entry::Occupied(mut e) => Some(e.insert(new)),
-            Entry::Vacant(e) => {
-                _ = e.insert(new).unwrap();
-                None
-            }
-        },
-        None => match entry {
-            Entry::Occupied(e) => Some(e.remove()),
-            Entry::Vacant(_) => None,
-        },
-    };
-}
-
-// Hash utilities
-
-struct SeaRandomState {
-    k1: u64,
-    k2: u64,
-    k3: u64,
-    k4: u64,
-}
-
-impl std::hash::BuildHasher for SeaRandomState {
-    type Hasher = seahash::SeaHasher;
-
-    fn build_hasher(&self) -> Self::Hasher {
-        seahash::SeaHasher::with_seeds(self.k1, self.k2, self.k3, self.k4)
-    }
-}
-
-impl SeaRandomState {
-    fn new() -> Self {
-        let mut rng = rand::rng();
-        Self {
-            k1: rng.random(),
-            k2: rng.random(),
-            k3: rng.random(),
-            k4: rng.random(),
-        }
-    }
-}
-
-fn small_benchs(c: &mut Criterion) {
-    let mut group = c.benchmark_group("Small maps");
-    group.sample_size(10);
-
-    group.bench_function("small_rehash", |b| {
-        let ideal_filled = 4_000_000;
-        let size = 5_000_000;
-        let mut writer = HashMapInit::new_resizeable(size, size * 2).attach_writer();
-        let mut rng = rand::rng();
-        while writer.get_num_buckets_in_use() < ideal_filled as usize {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            apply_op(TestOp(key, Some(val)), &mut writer);
-        }
-        b.iter(|| writer.shuffle());
-    });
-
-    group.bench_function("small_rehash_xxhash", |b| {
-        let ideal_filled = 4_000_000;
-        let size = 5_000_000;
-        let mut writer = HashMapInit::new_resizeable(size, size * 2)
-            .with_hasher(twox_hash::xxhash64::RandomState::default())
-            .attach_writer();
-        let mut rng = rand::rng();
-        while writer.get_num_buckets_in_use() < ideal_filled as usize {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            apply_op(TestOp(key, Some(val)), &mut writer);
-        }
-        b.iter(|| writer.shuffle());
-    });
-
-    group.bench_function("small_rehash_ahash", |b| {
-        let ideal_filled = 4_000_000;
-        let size = 5_000_000;
-        let mut writer = HashMapInit::new_resizeable(size, size * 2)
-            .with_hasher(ahash::RandomState::default())
-            .attach_writer();
-        let mut rng = rand::rng();
-        while writer.get_num_buckets_in_use() < ideal_filled as usize {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            apply_op(TestOp(key, Some(val)), &mut writer);
-        }
-        b.iter(|| writer.shuffle());
-    });
-
-    group.bench_function("small_rehash_seahash", |b| {
-        let ideal_filled = 4_000_000;
-        let size = 5_000_000;
-        let mut writer = HashMapInit::new_resizeable(size, size * 2)
-            .with_hasher(SeaRandomState::new())
-            .attach_writer();
-        let mut rng = rand::rng();
-        while writer.get_num_buckets_in_use() < ideal_filled as usize {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            apply_op(TestOp(key, Some(val)), &mut writer);
-        }
-        b.iter(|| writer.shuffle());
-    });
-
-    group.finish();
-}
-
-fn real_benchs(c: &mut Criterion) {
-    let mut group = c.benchmark_group("Realistic workloads");
-    group.sample_size(10);
-    group.bench_function("real_bulk_insert", |b| {
-        let size = 125_000_000;
-        let ideal_filled = 100_000_000;
-        let mut rng = rand::rng();
-        b.iter_batched(
-            || HashMapInit::new_resizeable(size, size * 2).attach_writer(),
-            |writer| {
-                for _ in 0..ideal_filled {
-                    let key: FileCacheKey = rng.random();
-                    let val = FileCacheEntry::dummy();
-                    let entry = writer.entry(key);
-                    match entry {
-                        Entry::Occupied(mut e) => {
-                            std::hint::black_box(e.insert(val));
-                        }
-                        Entry::Vacant(e) => {
-                            let _ = std::hint::black_box(e.insert(val).unwrap());
-                        }
-                    }
-                }
-            },
-            BatchSize::SmallInput,
-        )
-    });
-
-    group.bench_function("real_rehash", |b| {
-        let size = 125_000_000;
-        let ideal_filled = 100_000_000;
-        let mut writer = HashMapInit::new_resizeable(size, size).attach_writer();
-        let mut rng = rand::rng();
-        while writer.get_num_buckets_in_use() < ideal_filled {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            apply_op(TestOp(key, Some(val)), &mut writer);
-        }
-        b.iter(|| writer.shuffle());
-    });
-
-    group.bench_function("real_rehash_hashbrown", |b| {
-        let size = 125_000_000;
-        let ideal_filled = 100_000_000;
-        let mut writer = hashbrown::raw::RawTable::new();
-        let mut rng = rand::rng();
-        let hasher = rustc_hash::FxBuildHasher;
-        unsafe {
-            writer
-                .resize(
-                    size,
-                    |(k, _)| hasher.hash_one(k),
-                    hashbrown::raw::Fallibility::Infallible,
-                )
-                .unwrap();
-        }
-        while writer.len() < ideal_filled as usize {
-            let key: FileCacheKey = rng.random();
-            let val = FileCacheEntry::dummy();
-            writer.insert(hasher.hash_one(&key), (key, val), |(k, _)| {
-                hasher.hash_one(k)
-            });
-        }
-        b.iter(|| unsafe {
-            writer.table.rehash_in_place(
-                &|table, index| {
-                    hasher.hash_one(
-                        &table
-                            .bucket::<(FileCacheKey, FileCacheEntry)>(index)
-                            .as_ref()
-                            .0,
-                    )
-                },
-                std::mem::size_of::<(FileCacheKey, FileCacheEntry)>(),
-                if std::mem::needs_drop::<(FileCacheKey, FileCacheEntry)>() {
-                    Some(|ptr| std::ptr::drop_in_place(ptr as *mut (FileCacheKey, FileCacheEntry)))
-                } else {
-                    None
-                },
-            )
-        });
-    });
-
-    for elems in [2, 4, 8, 16, 32, 64, 96, 112] {
-        group.bench_with_input(
-            BenchmarkId::new("real_rehash_varied", elems),
-            &elems,
-            |b, &size| {
-                let ideal_filled = size * 1_000_000;
-                let size = 125_000_000;
-                let mut writer = HashMapInit::new_resizeable(size, size).attach_writer();
-                let mut rng = rand::rng();
-                while writer.get_num_buckets_in_use() < ideal_filled as usize {
-                    let key: FileCacheKey = rng.random();
-                    let val = FileCacheEntry::dummy();
-                    apply_op(TestOp(key, Some(val)), &mut writer);
-                }
-                b.iter(|| writer.shuffle());
-            },
-        );
-        group.bench_with_input(
-            BenchmarkId::new("real_rehash_varied_hashbrown", elems),
-            &elems,
-            |b, &size| {
-                let ideal_filled = size * 1_000_000;
-                let size = 125_000_000;
-                let mut writer = hashbrown::raw::RawTable::new();
-                let mut rng = rand::rng();
-                let hasher = rustc_hash::FxBuildHasher;
-                unsafe {
-                    writer
-                        .resize(
-                            size,
-                            |(k, _)| hasher.hash_one(k),
-                            hashbrown::raw::Fallibility::Infallible,
-                        )
-                        .unwrap();
-                }
-                while writer.len() < ideal_filled as usize {
-                    let key: FileCacheKey = rng.random();
-                    let val = FileCacheEntry::dummy();
-                    writer.insert(hasher.hash_one(&key), (key, val), |(k, _)| {
-                        hasher.hash_one(k)
-                    });
-                }
-                b.iter(|| unsafe {
-                    writer.table.rehash_in_place(
-                        &|table, index| {
-                            hasher.hash_one(
-                                &table
-                                    .bucket::<(FileCacheKey, FileCacheEntry)>(index)
-                                    .as_ref()
-                                    .0,
-                            )
-                        },
-                        std::mem::size_of::<(FileCacheKey, FileCacheEntry)>(),
-                        if std::mem::needs_drop::<(FileCacheKey, FileCacheEntry)>() {
-                            Some(|ptr| {
-                                std::ptr::drop_in_place(ptr as *mut (FileCacheKey, FileCacheEntry))
-                            })
-                        } else {
-                            None
-                        },
-                    )
-                });
-            },
-        );
-    }
-
-    group.finish();
-}
-
-criterion_group!(benches, small_benchs, real_benchs);
-criterion_main!(benches);

libs/neon-shmem/src/hash.rs

@@ -16,7 +16,6 @@
 //!
 //! Concurrency is managed very simply: the entire map is guarded by one shared-memory RwLock.
 
-use std::fmt::Debug;
 use std::hash::{BuildHasher, Hash};
 use std::mem::MaybeUninit;
 
@@ -41,75 +40,45 @@ pub enum HashMapShrinkError {
     #[error("shmem resize failed: {0}")]
     ResizeError(shmem::Error),
     /// Occupied entries in to-be-shrunk space were encountered beginning at the given index.
-    #[error("occupied entry in deallocated space found at {2} (in deallocated range of {0}..{1})")]
-    RemainingEntries(usize, usize, usize),
+    #[error("occupied entry in deallocated space found at {0}")]
+    RemainingEntries(usize),
 }
 
 /// This represents a hash table that (possibly) lives in shared memory.
 /// If a new process is launched with fork(), the child process inherits
 /// this struct.
 #[must_use]
-pub struct HashMapInit<K: 'static, V: 'static, S = rustc_hash::FxBuildHasher> {
+pub struct HashMapInit<'a, K, V, S = rustc_hash::FxBuildHasher> {
     shmem_handle: Option<ShmemHandle>,
-    shared_ptr: *mut HashMapShared<K, V>,
+    shared_ptr: *mut HashMapShared<'a, K, V>,
     shared_size: usize,
     hasher: S,
     num_buckets: u32,
 }
 
-impl<K, V, S> Debug for HashMapInit<K, V, S>
-where
-    K: Debug,
-    V: Debug,
-{
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("HashMapInit")
-            .field("shmem_handle", &self.shmem_handle)
-            .field("shared_ptr", &self.shared_ptr)
-            .field("shared_size", &self.shared_size)
-            // .field("hasher", &self.hasher)
-            .field("num_buckets", &self.num_buckets)
-            .finish()
-    }
-}
-
 /// This is a per-process handle to a hash table that (possibly) lives in shared memory.
 /// If a child process is launched with fork(), the child process should
 /// get its own HashMapAccess by calling HashMapInit::attach_writer/reader().
 ///
 /// XXX: We're not making use of it at the moment, but this struct could
 /// hold process-local information in the future.
-pub struct HashMapAccess<K: 'static, V: 'static, S = rustc_hash::FxBuildHasher> {
+pub struct HashMapAccess<'a, K, V, S = rustc_hash::FxBuildHasher> {
     shmem_handle: Option<ShmemHandle>,
-    shared_ptr: *mut HashMapShared<K, V>,
+    shared_ptr: *mut HashMapShared<'a, K, V>,
     hasher: S,
 }
 
-unsafe impl<K: Sync, V: Sync, S> Sync for HashMapAccess<K, V, S> {}
-unsafe impl<K: Send, V: Send, S> Send for HashMapAccess<K, V, S> {}
+unsafe impl<K: Sync, V: Sync, S> Sync for HashMapAccess<'_, K, V, S> {}
+unsafe impl<K: Send, V: Send, S> Send for HashMapAccess<'_, K, V, S> {}
 
-impl<K, V, S> Debug for HashMapAccess<K, V, S>
-where
-    K: Debug,
-    V: Debug,
-{
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("HashMapAccess")
-            .field("shmem_handle", &self.shmem_handle)
-            .field("shared_ptr", &self.shared_ptr)
-            // .field("hasher", &self.hasher)
-            .finish()
-    }
-}
-
-impl<K: Clone + Hash + Eq + 'static, V: 'static, S> HashMapInit<K, V, S> {
+impl<'a, K: Clone + Hash + Eq, V, S> HashMapInit<'a, K, V, S> {
     /// Change the 'hasher' used by the hash table.
     ///
     /// NOTE: This must be called right after creating the hash table,
     /// before inserting any entries and before calling attach_writer/reader.
     /// Otherwise different accessors could be using different hash function,
     /// with confusing results.
-    pub fn with_hasher<T: BuildHasher>(self, hasher: T) -> HashMapInit<K, V, T> {
+    pub fn with_hasher<T: BuildHasher>(self, hasher: T) -> HashMapInit<'a, K, V, T> {
         HashMapInit {
             hasher,
             shmem_handle: self.shmem_handle,
@@ -177,7 +146,7 @@ impl<K: Clone + Hash + Eq + 'static, V: 'static, S> HashMapInit<K, V, S> {
     }
 
     /// Attach to a hash table for writing.
-    pub fn attach_writer(self) -> HashMapAccess<K, V, S> {
+    pub fn attach_writer(self) -> HashMapAccess<'a, K, V, S> {
         HashMapAccess {
             shmem_handle: self.shmem_handle,
             shared_ptr: self.shared_ptr,
@@ -189,7 +158,7 @@ impl<K: Clone + Hash + Eq + 'static, V: 'static, S> HashMapInit<K, V, S> {
     ///
     /// This is a holdover from a previous implementation and is being kept around for
     /// backwards compatibility reasons.
-    pub fn attach_reader(self) -> HashMapAccess<K, V, S> {
+    pub fn attach_reader(self) -> HashMapAccess<'a, K, V, S> {
         self.attach_writer()
     }
 }
@@ -206,14 +175,14 @@ impl<K: Clone + Hash + Eq + 'static, V: 'static, S> HashMapInit<K, V, S> {
 /// dictionary
 ///
 /// In between the above parts, there can be padding bytes to align the parts correctly.
-type HashMapShared<K, V> = RwLock<CoreHashMap<K, V>>;
+type HashMapShared<'a, K, V> = RwLock<CoreHashMap<'a, K, V>>;
 
-impl<K, V: 'static> HashMapInit<K, V, rustc_hash::FxBuildHasher>
+impl<'a, K, V> HashMapInit<'a, K, V, rustc_hash::FxBuildHasher>
 where
-    K: Clone + Hash + Eq + 'static,
+    K: Clone + Hash + Eq,
 {
     /// Place the hash table within a user-supplied fixed memory area.
-    pub fn with_fixed(num_buckets: u32, area: &'static mut [MaybeUninit<u8>]) -> Self {
+    pub fn with_fixed(num_buckets: u32, area: &'a mut [MaybeUninit<u8>]) -> Self {
         Self::new(
             num_buckets,
             None,
@@ -269,10 +238,9 @@ where
     }
 }
 
-impl<K, V, S: BuildHasher> HashMapAccess<K, V, S>
+impl<'a, K, V, S: BuildHasher> HashMapAccess<'a, K, V, S>
 where
-    K: Clone + Hash + Eq + 'static,
-	V: 'static
+    K: Clone + Hash + Eq,
 {
     /// Hash a key using the map's hasher.
     #[inline]
@@ -280,7 +248,7 @@ where
         self.hasher.hash_one(key)
     }
 
-    fn entry_with_hash(&self, key: K, hash: u64) -> Entry<'_, K, V> {
+    fn entry_with_hash(&self, key: K, hash: u64) -> Entry<'a, '_, K, V> {
         let mut map = unsafe { self.shared_ptr.as_ref() }.unwrap().write();
         let dict_pos = hash as usize % map.dictionary.len();
         let first = map.dictionary[dict_pos];
@@ -330,9 +298,9 @@ where
 
     /// Get a reference to the entry containing a key.
     ///
-    /// NB: This takes a write lock as there's no way to distinguish whether the intention
+    /// NB: THis takes a write lock as there's no way to distinguish whether the intention
     /// is to use the entry for reading or for writing in advance.
-    pub fn entry(&self, key: K) -> Entry<'_, K, V> {
+    pub fn entry(&self, key: K) -> Entry<'a, '_, K, V> {
         let hash = self.get_hash_value(&key);
         self.entry_with_hash(key, hash)
     }
@@ -366,7 +334,7 @@ where
     /// Has more overhead than one would intuitively expect: performs both a clone of the key
     /// due to the [`OccupiedEntry`] type owning the key and also a hash of the key in order
     /// to enable repairing the hash chain if the entry is removed.
-    pub fn entry_at_bucket(&self, pos: usize) -> Option<OccupiedEntry<'_, K, V>> {
+    pub fn entry_at_bucket(&self, pos: usize) -> Option<OccupiedEntry<'a, '_, K, V>> {
         let map = unsafe { self.shared_ptr.as_mut() }.unwrap().write();
         if pos >= map.buckets.len() {
             return None;
@@ -390,16 +358,6 @@ where
         map.get_num_buckets()
     }
 
-	/// Returns the logical number of buckets in the table (aka the amount of allocatable buckets).
-	pub fn get_num_logical_buckets(&self) -> usize {
-        let map = unsafe { self.shared_ptr.as_ref() }.unwrap().read();
-		if map.alloc_limit == INVALID_POS {
-			map.get_num_buckets()
-		} else {
-			map.alloc_limit as usize
-		}
-    }
-
     /// Return the key and value stored in bucket with given index. This can be used to
     /// iterate through the hash map.
     // TODO: An Iterator might be nicer. The communicator's clock algorithm needs to
@@ -441,7 +399,7 @@ where
     /// in the process.
     fn rehash_dict(
         &self,
-        inner: &mut CoreHashMap<K, V>,
+        inner: &mut CoreHashMap<'a, K, V>,
         buckets_ptr: *mut core::Bucket<K, V>,
         end_ptr: *mut u8,
         num_buckets: u32,
@@ -552,12 +510,12 @@ where
     /// # Panics
     /// Panics if called on a map initialized with [`HashMapInit::with_fixed`] or if `num_buckets` is
     /// greater than the number of buckets in the map.
-    pub fn begin_shrink(&self, num_buckets: u32) {
+    pub fn begin_shrink(&mut self, num_buckets: u32) {
         let mut map = unsafe { self.shared_ptr.as_mut() }.unwrap().write();
-        // assert!(
-        //     num_buckets <= map.get_num_buckets() as u32,
-        //     "shrink called with a larger number of buckets"
-        // );
+        assert!(
+            num_buckets <= map.get_num_buckets() as u32,
+            "shrink called with a larger number of buckets"
+        );
         _ = self
             .shmem_handle
             .as_ref()
@@ -602,9 +560,7 @@ where
 
         for i in (num_buckets as usize)..map.buckets.len() {
             if map.buckets[i].inner.is_some() {
-                return Err(HashMapShrinkError::RemainingEntries(
-					num_buckets as usize, map.buckets.len(), i)
-				);
+                return Err(HashMapShrinkError::RemainingEntries(i));
             }
         }
 

libs/neon-shmem/src/hash/core.rs

@@ -1,6 +1,5 @@
 //! Simple hash table with chaining.
 
-use std::fmt::Debug;
 use std::hash::Hash;
 use std::mem::MaybeUninit;
 
@@ -18,25 +17,12 @@ pub(crate) struct Bucket<K, V> {
     pub(crate) inner: Option<(K, V)>,
 }
 
-impl<K, V> Debug for Bucket<K, V>
-where
-    K: Debug,
-    V: Debug,
-{
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("Bucket")
-            .field("next", &self.next)
-            .field("inner", &self.inner)
-            .finish()
-    }
-}
-
 /// Core hash table implementation.
-pub(crate) struct CoreHashMap<K: 'static, V: 'static> {
+pub(crate) struct CoreHashMap<'a, K, V> {
     /// Dictionary used to map hashes to bucket indices.
-    pub(crate) dictionary: &'static mut [u32],
+    pub(crate) dictionary: &'a mut [u32],
     /// Buckets containing key-value pairs.
-    pub(crate) buckets: &'static mut [Bucket<K, V>],
+    pub(crate) buckets: &'a mut [Bucket<K, V>],
     /// Head of the freelist.
     pub(crate) free_head: u32,
     /// Maximum index of a bucket allowed to be allocated. [`INVALID_POS`] if no limit.
@@ -45,27 +31,11 @@ pub(crate) struct CoreHashMap<K: 'static, V: 'static> {
     pub(crate) buckets_in_use: u32,
 }
 
-impl<K, V> Debug for CoreHashMap<K, V>
-where
-    K: Debug,
-    V: Debug,
-{
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.debug_struct("CoreHashMap")
-            .field("dictionary", &self.dictionary)
-            .field("buckets", &self.buckets)
-            .field("free_head", &self.free_head)
-            .field("alloc_limit", &self.alloc_limit)
-            .field("buckets_in_use", &self.buckets_in_use)
-            .finish()
-    }
-}
-
 /// Error for when there are no empty buckets left but one is needed.
 #[derive(Debug, PartialEq)]
 pub struct FullError;
 
-impl<K: Clone + Hash + Eq, V> CoreHashMap<K, V> {
+impl<'a, K: Clone + Hash + Eq, V> CoreHashMap<'a, K, V> {
     const FILL_FACTOR: f32 = 0.60;
 
     /// Estimate the size of data contained within the the hash map.
@@ -83,8 +53,8 @@ impl<K: Clone + Hash + Eq, V> CoreHashMap<K, V> {
     }
 
     pub fn new(
-        buckets: &'static mut [MaybeUninit<Bucket<K, V>>],
-        dictionary: &'static mut [MaybeUninit<u32>],
+        buckets: &'a mut [MaybeUninit<Bucket<K, V>>],
+        dictionary: &'a mut [MaybeUninit<u32>],
     ) -> Self {
         // Initialize the buckets
         for i in 0..buckets.len() {

libs/neon-shmem/src/hash/entry.rs

@@ -6,9 +6,9 @@ use crate::sync::{RwLockWriteGuard, ValueWriteGuard};
 use std::hash::Hash;
 use std::mem;
 
-pub enum Entry<'b, K: 'static, V: 'static> {
-    Occupied(OccupiedEntry<'b, K, V>),
-    Vacant(VacantEntry<'b, K, V>),
+pub enum Entry<'a, 'b, K, V> {
+    Occupied(OccupiedEntry<'a, 'b, K, V>),
+    Vacant(VacantEntry<'a, 'b, K, V>),
 }
 
 /// Enum representing the previous position within a chain.
@@ -22,9 +22,9 @@ pub(crate) enum PrevPos {
     Unknown(u64),
 }
 
-pub struct OccupiedEntry<'b, K: 'static, V: 'static> {
+pub struct OccupiedEntry<'a, 'b, K, V> {
     /// Mutable reference to the map containing this entry.
-    pub(crate) map: RwLockWriteGuard<'b, CoreHashMap<K, V>>,
+    pub(crate) map: RwLockWriteGuard<'b, CoreHashMap<'a, K, V>>,
     /// The key of the occupied entry
     pub(crate) _key: K,
     /// The index of the previous entry in the chain.
@@ -33,7 +33,7 @@ pub struct OccupiedEntry<'b, K: 'static, V: 'static> {
     pub(crate) bucket_pos: u32,
 }
 
-impl<K: 'static, V: 'static> OccupiedEntry<'_, K, V> {
+impl<K, V> OccupiedEntry<'_, '_, K, V> {
     pub fn get(&self) -> &V {
         &self.map.buckets[self.bucket_pos as usize]
             .inner
@@ -61,10 +61,6 @@ impl<K: 'static, V: 'static> OccupiedEntry<'_, K, V> {
     ///
     /// This may result in multiple bucket accesses if the entry was obtained by index as the
     /// previous chain entry needs to be discovered in this case.
-    ///
-    /// # Panics
-    /// Panics if the `prev_pos` field is equal to [`PrevPos::Unknown`]. In practice, this means
-    /// the entry was obtained via calling something like [`super::HashMapAccess::entry_at_bucket`].
     pub fn remove(mut self) -> V {
         // If this bucket was queried by index, go ahead and follow its chain from the start.
         let prev = if let PrevPos::Unknown(hash) = self.prev_pos {
@@ -108,16 +104,16 @@ impl<K: 'static, V: 'static> OccupiedEntry<'_, K, V> {
 }
 
 /// An abstract view into a vacant entry within the map.
-pub struct VacantEntry<'b, K: 'static, V: 'static> {
+pub struct VacantEntry<'a, 'b, K, V> {
     /// Mutable reference to the map containing this entry.
-    pub(crate) map: RwLockWriteGuard<'b, CoreHashMap<K, V>>,
+    pub(crate) map: RwLockWriteGuard<'b, CoreHashMap<'a, K, V>>,
     /// The key to be inserted into this entry.
     pub(crate) key: K,
     /// The position within the dictionary corresponding to the key's hash.
     pub(crate) dict_pos: u32,
 }
 
-impl<'b, K: Clone + Hash + Eq + 'static, V: 'static> VacantEntry<'b, K, V> {
+impl<'b, K: Clone + Hash + Eq, V> VacantEntry<'_, 'b, K, V> {
     /// Insert a value into the vacant entry, finding and populating an empty bucket in the process.
     ///
     /// # Errors

libs/neon-shmem/src/shmem.rs

@@ -21,7 +21,6 @@ use nix::unistd::ftruncate as nix_ftruncate;
 /// the underlying file is resized. Do not access the area beyond the current size. Currently, that
 /// will cause the file to be expanded, but we might use `mprotect()` etc. to enforce that in the
 /// future.
-#[derive(Debug)]
 pub struct ShmemHandle {
     /// memfd file descriptor
     fd: OwnedFd,
@@ -36,7 +35,6 @@ pub struct ShmemHandle {
 }
 
 /// This is stored at the beginning in the shared memory area.
-#[derive(Debug)]
 struct SharedStruct {
     max_size: usize,
 

libs/utils/src/lsn.rs

@@ -310,11 +310,6 @@ impl AtomicLsn {
         }
     }
 
-    /// Consumes the atomic and returns the contained value.
-    pub const fn into_inner(self) -> Lsn {
-        Lsn(self.inner.into_inner())
-    }
-
     /// Atomically retrieve the `Lsn` value from memory.
     pub fn load(&self) -> Lsn {
         Lsn(self.inner.load(Ordering::Acquire))

pageserver/Cargo.toml

@@ -54,7 +54,6 @@ pageserver_api.workspace = true
 pageserver_client.workspace = true # for ResponseErrorMessageExt TOOD refactor that
 pageserver_compaction.workspace = true
 pageserver_page_api.workspace = true
-peekable.workspace = true
 pem.workspace = true
 pin-project-lite.workspace = true
 postgres_backend.workspace = true
@@ -67,7 +66,6 @@ postgres-types.workspace = true
 posthog_client_lite.workspace = true
 pprof.workspace = true
 pq_proto.workspace = true
-prost.workspace = true
 rand.workspace = true
 range-set-blaze = { version = "0.1.16", features = ["alloc"] }
 regex.workspace = true

pageserver/client_grpc/src/lib.rs

@@ -3,4 +3,3 @@ mod pool;
 mod retry;
 
 pub use client::{PageserverClient, ShardSpec};
-pub use pageserver_api::shard::ShardStripeSize; // used in ShardSpec

pageserver/page_api/src/model.rs

@@ -33,8 +33,6 @@ pub enum ProtocolError {
     Invalid(&'static str, String),
     #[error("required field '{0}' is missing")]
     Missing(&'static str),
-    #[error("invalid combination of not_modified_lsn '{0}' and request_lsn '{1}'")]
-    InvalidLsns(Lsn, Lsn),
 }
 
 impl ProtocolError {
@@ -87,9 +85,9 @@ impl TryFrom<proto::ReadLsn> for ReadLsn {
             return Err(ProtocolError::invalid("request_lsn", pb.request_lsn));
         }
         if pb.not_modified_since_lsn > pb.request_lsn {
-            return Err(ProtocolError::InvalidLsns(
-                Lsn(pb.not_modified_since_lsn),
-                Lsn(pb.request_lsn),
+            return Err(ProtocolError::invalid(
+                "not_modified_since_lsn",
+                pb.not_modified_since_lsn,
             ));
         }
         Ok(Self {

pageserver/pagebench/Cargo.toml

@@ -25,9 +25,6 @@ tracing.workspace = true
 tokio.workspace = true
 tokio-stream.workspace = true
 tokio-util.workspace = true
-axum.workspace = true
-http.workspace = true
-metrics.workspace = true
 tonic.workspace = true
 url.workspace = true
 

pageserver/pagebench/src/cmd/getpage_latest_lsn.rs

@@ -34,10 +34,6 @@ use crate::util::{request_stats, tokio_thread_local_stats};
 /// GetPage@LatestLSN, uniformly distributed across the compute-accessible keyspace.
 #[derive(clap::Parser)]
 pub(crate) struct Args {
-    #[clap(long, default_value = "false")]
-    grpc: bool,
-    #[clap(long, default_value = "false")]
-    grpc_stream: bool,
     #[clap(long, default_value = "http://localhost:9898")]
     mgmt_api_endpoint: String,
     /// Pageserver connection string. Supports postgresql:// and grpc:// protocols.
@@ -82,9 +78,6 @@ pub(crate) struct Args {
     #[clap(long)]
     set_io_mode: Option<pageserver_api::models::virtual_file::IoMode>,
 
-    #[clap(long)]
-    only_relnode: Option<u32>,
-
     /// Queue depth generated in each client.
     #[clap(long, default_value = "1")]
     queue_depth: NonZeroUsize,
@@ -99,31 +92,10 @@ pub(crate) struct Args {
     #[clap(long, default_value = "1")]
     batch_size: NonZeroUsize,
 
+    #[clap(long)]
+    only_relnode: Option<u32>,
+
     targets: Option<Vec<TenantTimelineId>>,
-
-    #[clap(long, default_value = "100")]
-    pool_max_consumers: NonZeroUsize,
-
-    #[clap(long, default_value = "5")]
-    pool_error_threshold: NonZeroUsize,
-
-    #[clap(long, default_value = "5000")]
-    pool_connect_timeout: NonZeroUsize,
-
-    #[clap(long, default_value = "1000")]
-    pool_connect_backoff: NonZeroUsize,
-
-    #[clap(long, default_value = "60000")]
-    pool_max_idle_duration: NonZeroUsize,
-
-    #[clap(long, default_value = "0")]
-    max_delay_ms: usize,
-
-    #[clap(long, default_value = "0")]
-    percent_drops: usize,
-
-    #[clap(long, default_value = "0")]
-    percent_hangs: usize,
 }
 
 /// State shared by all clients
@@ -180,6 +152,7 @@ pub(crate) fn main(args: Args) -> anyhow::Result<()> {
         main_impl(args, thread_local_stats)
     })
 }
+
 async fn main_impl(
     args: Args,
     all_thread_local_stats: AllThreadLocalStats<request_stats::Stats>,
@@ -344,7 +317,6 @@ async fn main_impl(
     let rps_period = args
         .per_client_rate
         .map(|rps_limit| Duration::from_secs_f64(1.0 / (rps_limit as f64)));
-
     let make_worker: &dyn Fn(WorkerId) -> Pin<Box<dyn Send + Future<Output = ()>>> = &|worker_id| {
         let ss = shared_state.clone();
         let cancel = cancel.clone();

pageserver/src/page_service.rs

@@ -453,7 +453,6 @@ impl TimelineHandles {
             handles: Default::default(),
         }
     }
-
     async fn get(
         &mut self,
         tenant_id: TenantId,

pgxn/neon/Makefile

@@ -5,12 +5,10 @@ MODULE_big = neon
 OBJS = \
 	$(WIN32RES) \
 	communicator.o \
-	communicator_new.o \
 	communicator_process.o \
 	extension_server.o \
 	file_cache.o \
 	hll.o \
-	lfc_prewarm.o \
 	libpagestore.o \
 	logical_replication_monitor.o \
 	neon.o \
@@ -69,7 +67,6 @@ WALPROP_OBJS = \
 
 # libcommunicator.a is built by cargo from the Rust sources under communicator/
 # subdirectory. `cargo build` also generates communicator_bindings.h.
-communicator_new.o: communicator/communicator_bindings.h
 communicator_process.o: communicator/communicator_bindings.h
 file_cache.o: communicator/communicator_bindings.h
 

pgxn/neon/communicator/Cargo.toml

@@ -17,36 +17,14 @@ rest_broker = []
 
 [dependencies]
 axum.workspace = true
-bytes.workspace = true
-clashmap.workspace = true
 http.workspace = true
-libc.workspace = true
-nix.workspace = true
-atomic_enum = "0.3.0"
-measured.workspace = true
-prometheus.workspace = true
-prost.workspace = true
-strum_macros.workspace = true
-thiserror.workspace = true
-tonic = { workspace = true, default-features = false, features=["codegen", "prost", "transport"] }
 tokio = { workspace = true, features = ["macros", "net", "io-util", "rt", "rt-multi-thread"] }
-tokio-pipe = { version = "0.2.12" }
 tracing.workspace = true
 tracing-subscriber.workspace = true
 
-uring-common = { workspace = true, features = ["bytes"] }
-
-pageserver_client_grpc.workspace = true
-pageserver_api.workspace = true
-pageserver_page_api.workspace = true
-
-neon-shmem.workspace = true
+measured.workspace = true
 utils.workspace = true
 workspace_hack = { version = "0.1", path = "../../../workspace_hack" }
 
-[target.'cfg(target_os = "linux")'.dependencies]
-fiemap = "0.1.3"
-itertools.workspace = true
-
 [build-dependencies]
 cbindgen.workspace = true

pgxn/neon/communicator/README.md

@@ -3,18 +3,9 @@
 This package provides the so-called "compute-pageserver communicator",
 or just "communicator" in short. The communicator is a separate
 background worker process that runs in the PostgreSQL server. It's
-part of the neon extension.
-
-The commuicator handles the communication with the pageservers, and
-also provides an HTTP endpoint for metrics over a local Unix Domain
-socket (aka. the "communicator control socket"). On the PostgreSQL
-side, the glue code in pgxn/neon/ uses the communicator to implement
-the PostgreSQL Storage Manager (SMGR) interface.
-
-## Design criteria
-
-- Low latency
-- Saturate a 10 Gbit / s network interface without becoming a bottleneck
+part of the neon extension. Currently, it only provides an HTTP
+endpoint for metrics, but in the future it will evolve to handle all
+communications with the pageservers.
 
 ## Source code view
 
@@ -23,122 +14,10 @@ pgxn/neon/communicator_process.c
     the glue that interacts with PostgreSQL code and the Rust
     code in the communicator process.
 
-pgxn/neon/communicator_new.c
-	Contains the backend code that interacts with the communicator
-	process.
 
-pgxn/neon/communicator/src/backend_interface.rs
-	The entry point for calls from each backend.
-
-pgxn/neon/communicator/src/init.rs
-	Initialization at server startup
+pgxn/neon/communicator/src/worker_process/
+    Worker process main loop and glue code
 
 At compilation time, pgxn/neon/communicator/ produces a static
 library, libcommunicator.a. It is linked to the neon.so extension
 library.
-
-The real networking code, which is independent of PostgreSQL, is in
-the pageserver/client_grpc crate.
-
-## Process view
-
-The communicator runs in a dedicated background worker process, the
-"communicator process". The communicator uses a multi-threaded Tokio
-runtime to execute the IO requests. So the communicator process has
-multiple threads running. That's unusual for Postgres processes and
-care must be taken to make that work.
-
-### Backend <-> worker communication
-
-Each backend has a number of I/O request slots in shared memory. The
-slots are statically allocated for each backend, and must not be
-accessed by other backends. The worker process reads requests from the
-shared memory slots, and writes responses back to the slots.
-
-Here's an example snapshot of the system, when two requests from two
-different backends are in progress:
-
-```
-Backends           Request slots          Communicator process
----------          -------------          --------------------
-
-Backend 1          1: Idle
-                   2: Idle
-                   3: Processing          tokio task handling request 3
-
-Backend 2          4: Completed
-                   5: Processing          tokio task handling request 5
-                   6: Idle
-
-...                ...
-```
-
-To submit an IO request, the backend first picks one of its Idle
-slots, writes the IO request in the slot, and updates it to
-'Submitted' state. That transfers the ownership of the slot to the
-worker process, until the worker process marks the request as
-Completed. The worker process spawns a separate Tokio task for each
-request.
-
-To inform the worker process that a request slot has a pending IO
-request, there's a pipe shared by the worker process and all backend
-processes. The backend writes the index of the request slot to the
-pipe after changing the slot's state to Submitted. This wakes up the
-worker process.
-
-(Note that the pipe is just used for wakeups, but the worker process
-is free to pick up Submitted IO requests even without receiving the
-wakeup. As of this writing, it doesn't do that, but it might be useful
-in the future to reduce latency even further, for example.)
-
-When the worker process has completed processing the request, it
-writes the result back in the request slot. A GetPage request can also
-contain a pointer to buffer in the shared buffer cache. In that case,
-the worker process writes the resulting page contents directly to the
-buffer, and just a result code in the request slot. It then updates
-the 'state' field to Completed, which passes the owner ship back to
-the originating backend. Finally, it signals the process Latch of the
-originating backend, waking it up.
-
-### Differences between PostgreSQL v16, v17 and v18
-
-PostgreSQL v18 introduced the new AIO mechanism. The PostgreSQL AIO
-mechanism uses a very similar mechanism as described in the previous
-section, for the communication between AIO worker processes and
-backends. With our communicator, the AIO worker processes are not
-used, but we use the same PgAioHandle request slots as in upstream.
-For Neon-specific IO requests like GetDbSize, a neon request slot is
-used. But for the actual IO requests, the request slot merely contains
-a pointer to the PgAioHandle slot. The worker process updates the
-status of that, calls the IO callbacks upon completionetc, just like
-the upstream AIO worker processes do.
-
-## Sequence diagram
-
-                      neon
-    PostgreSQL     extension       backend_interface.rs  worker_process.rs    processor    tonic
-       |               .                    .                   .                 .
-	   | smgr_read()   .                    .                   .                 .
-	   +-------------> +                    .                   .                 .
-	   .               |                    .                   .                 .
-	   .               |  rcommunicator_    .                   .                 .
-	   .               | get_page_at_lsn    .                   .                 .
-	   .               +------------------> +                   .                 .
-                                            |                   .                 .
-                                            | write request to  .                 .                 .
-                                            | slot              .                 .
-                                            |                   .                 .
-                                            |                   .                 .
-											| submit_request()  .                 .
-											+-----------------> +                 .
-											|                   |                 .
-											|					| db_size_request .               .
-																+---------------->.
-																                  . TODO
-
-
-
-### Compute <-> pageserver protocol
-
-The protocol between Compute and the pageserver is based on gRPC. See `protos/`.
-

pgxn/neon/communicator/src/backend_comms.rs

@@ -1,224 +0,0 @@
-//! This module implements a request/response "slot" for submitting
-//! requests from backends to the communicator process.
-//!
-//! NB: The "backend" side of this code runs in Postgres backend processes,
-//! which means that it is not safe to use the 'tracing' crate for logging, nor
-//! to launch threads or use tokio tasks!
-
-use std::cell::UnsafeCell;
-use std::sync::atomic::{AtomicI32, Ordering};
-
-use crate::neon_request::{NeonIORequest, NeonIOResult};
-
-use atomic_enum::atomic_enum;
-
-/// One request/response slot. Each backend has its own set of slots that it
-/// uses.
-///
-/// This is the moral equivalent of PgAioHandle for Postgres AIO requests
-/// Like PgAioHandle, try to keep this small.
-///
-/// There is an array of these in shared memory. Therefore, this must be Sized.
-///
-/// ## Lifecycle of a request
-///
-/// A slot is always owned by either the backend process or the communicator
-/// process, depending on the 'state'. Only the owning process is allowed to
-/// read or modify the slot, except for reading the 'state' itself to check who
-/// owns it.
-///
-/// A slot begins in the Idle state, where it is owned by the backend process.
-/// To submit a request, the backend process fills the slot with the request
-/// data, and changes it to the Submitted state. After changing the state, the
-/// slot is owned by the communicator process, and the backend is not allowed
-/// to access it until the communicator process marks it as Completed.
-///
-/// When the communicator process sees that the slot is in Submitted state, it
-/// starts to process the request. After processing the request, it stores the
-/// result in the slot, and changes the state to Completed. It is now owned by
-/// the backend process again, which may now read the result, and reuse the
-/// slot for a new request.
-///
-/// For correctness of the above protocol, we really only need two states:
-/// "owned by backend" and "owned by communicator process". But to help with
-/// debugging and better assertions, there are a few more states. When the
-/// backend starts to fill in the request details in the slot, it first sets the
-/// state from Idle to Filling, and when it's done with that, from Filling to
-/// Submitted. In the Filling state, the slot is still owned by the
-/// backend. Similarly, when the communicator process starts to process a
-/// request, it sets it to Processing state first, but the slot is still owned
-/// by the communicator process.
-///
-/// This struct doesn't handle waking up the communicator process when a request
-/// has been submitted or when a response is ready. The 'owner_procno' is used
-/// for waking up the backend on completion, but that happens elsewhere.
-pub struct NeonIORequestSlot {
-    /// similar to PgAioHandleState
-    state: AtomicNeonIORequestSlotState,
-
-    /// The owning process's ProcNumber. The worker process uses this to set the
-    /// process's latch on completion.
-    ///
-    /// (This could be calculated from num_neon_request_slots_per_backend and
-    /// the index of this slot in the overall 'neon_requst_slots array'. But we
-    /// prefer the communicator process to not know how the request slots are
-    /// divided between the backends.)
-    owner_procno: AtomicI32,
-
-    /// SAFETY: This is modified by submit_request(), after it has established
-    /// ownership of the slot by setting state from Idle to Filling
-    request: UnsafeCell<NeonIORequest>,
-
-    /// Valid when state is Completed
-    ///
-    /// SAFETY: This is modified by RequestProcessingGuard::complete(). There
-    /// can be only one RequestProcessingGuard outstanding for a slot at a time,
-    /// because it is returned by start_processing_request() which checks the
-    /// state, so RequestProcessingGuard has exclusive access to the slot.
-    result: UnsafeCell<NeonIOResult>,
-}
-
-// The protocol described in the "Lifecycle of a request" section above ensures
-// the safe access to the fields
-unsafe impl Send for NeonIORequestSlot {}
-unsafe impl Sync for NeonIORequestSlot {}
-
-impl Default for NeonIORequestSlot {
-    fn default() -> NeonIORequestSlot {
-        NeonIORequestSlot {
-            owner_procno: AtomicI32::new(-1),
-            request: UnsafeCell::new(NeonIORequest::Empty),
-            result: UnsafeCell::new(NeonIOResult::Empty),
-            state: AtomicNeonIORequestSlotState::new(NeonIORequestSlotState::Idle),
-        }
-    }
-}
-
-#[atomic_enum]
-#[derive(Eq, PartialEq)]
-pub enum NeonIORequestSlotState {
-    Idle,
-
-    /// Backend is filling in the request
-    Filling,
-
-    /// Backend has submitted the request to the communicator, but the
-    /// communicator process has not yet started processing it.
-    Submitted,
-
-    /// Communicator is processing the request
-    Processing,
-
-    /// Communicator has completed the request, and the 'result' field is now
-    /// valid, but the backend has not read the result yet.
-    Completed,
-}
-
-impl NeonIORequestSlot {
-    /// Write a request to the slot, and mark it as Submitted.
-    ///
-    /// Note: This does not wake up the worker process to actually process
-    /// the request. It's the caller's responsibility to do that.
-    pub fn submit_request(&self, request: &NeonIORequest, proc_number: i32) {
-        // Verify that the slot is in Idle state previously, and put it in
-        // Filling state.
-        //
-        // XXX: This step isn't strictly necessary. Assuming the caller didn't
-        // screw up and try to use a slot that's already in use, we could fill
-        // the slot and switch it directly from Idle to Submitted state.
-        if let Err(s) = self.state.compare_exchange(
-            NeonIORequestSlotState::Idle,
-            NeonIORequestSlotState::Filling,
-            Ordering::Relaxed,
-            Ordering::Relaxed,
-        ) {
-            panic!("unexpected state in request slot: {s:?}");
-        }
-
-        // Fill in the request details
-        self.owner_procno.store(proc_number, Ordering::Relaxed);
-        unsafe { *self.request.get() = *request }
-
-        // This synchronizes-with store/swap in [`start_processing_request`].
-        // Note that this ensures that the previous non-atomic writes visible
-        // to other threads too.
-        self.state
-            .store(NeonIORequestSlotState::Submitted, Ordering::Release);
-    }
-
-    pub fn get_state(&self) -> NeonIORequestSlotState {
-        self.state.load(Ordering::Relaxed)
-    }
-
-    pub fn try_get_result(&self) -> Option<NeonIOResult> {
-        // This synchronizes-with the store/swap in [`RequestProcessingGuard::completed`]
-        let state = self.state.load(Ordering::Acquire);
-        if state == NeonIORequestSlotState::Completed {
-            let result = unsafe { *self.result.get() };
-            self.state
-                .store(NeonIORequestSlotState::Idle, Ordering::Relaxed);
-            Some(result)
-        } else {
-            None
-        }
-    }
-
-    /// Read the IO request from the slot indicated in the wakeup
-    pub fn start_processing_request<'a>(&'a self) -> Option<RequestProcessingGuard<'a>> {
-        // XXX: using atomic load rather than compare_exchange would be
-        // sufficient here, as long as the communicator process has _some_ means
-        // of tracking which requests it's already processing. That could be a
-        // flag somewhere in communicator's private memory, for example.
-        //
-        // This synchronizes-with the store in [`submit_request`].
-        if let Err(s) = self.state.compare_exchange(
-            NeonIORequestSlotState::Submitted,
-            NeonIORequestSlotState::Processing,
-            Ordering::Acquire,
-            Ordering::Relaxed,
-        ) {
-            // FIXME surprising state. This is unexpected at the moment, but if we
-            // started to process requests more aggressively, without waiting for the
-            // read from the pipe, then this could happen
-            panic!("unexpected state in request slot: {s:?}");
-        }
-
-        Some(RequestProcessingGuard(self))
-    }
-}
-
-/// [`NeonIORequestSlot::start_processing_request`] returns this guard object to
-/// indicate that the the caller now "owns" the slot, until it calls
-/// [`RequestProcessingGuard::completed`].
-///
-/// TODO: implement Drop on this, to mark the request as Aborted or Errored
-/// if [`RequestProcessingGuard::completed`] is not called.
-pub struct RequestProcessingGuard<'a>(&'a NeonIORequestSlot);
-
-unsafe impl<'a> Send for RequestProcessingGuard<'a> {}
-unsafe impl<'a> Sync for RequestProcessingGuard<'a> {}
-
-impl<'a> RequestProcessingGuard<'a> {
-    pub fn get_request(&self) -> &NeonIORequest {
-        unsafe { &*self.0.request.get() }
-    }
-
-    pub fn get_owner_procno(&self) -> i32 {
-        self.0.owner_procno.load(Ordering::Relaxed)
-    }
-
-    pub fn completed(self, result: NeonIOResult) {
-        // Store the result to the slot.
-        unsafe {
-            *self.0.result.get() = result;
-        };
-
-        // Mark the request as completed. After that, we no longer have
-        // ownership of the slot, and must not modify it.
-        let old_state = self
-            .0
-            .state
-            .swap(NeonIORequestSlotState::Completed, Ordering::Release);
-        assert!(old_state == NeonIORequestSlotState::Processing);
-    }
-}

pgxn/neon/communicator/src/backend_interface.rs

@@ -1,296 +0,0 @@
-//! This code runs in each backend process. That means that launching Rust threads, panicking
-//! etc. is forbidden!
-
-use std::os::fd::OwnedFd;
-
-use crate::backend_comms::NeonIORequestSlot;
-use crate::init::CommunicatorInitStruct;
-use crate::integrated_cache::{BackendCacheReadOp, IntegratedCacheReadAccess};
-use crate::neon_request::{CCachedGetPageVResult, CLsn, COid};
-use crate::neon_request::{NeonIORequest, NeonIOResult};
-
-use utils::lsn::Lsn;
-
-pub struct CommunicatorBackendStruct<'t> {
-    my_proc_number: i32,
-
-    neon_request_slots: &'t [NeonIORequestSlot],
-
-    submission_pipe_write_fd: OwnedFd,
-
-    pending_cache_read_op: Option<BackendCacheReadOp<'t>>,
-
-    integrated_cache: &'t IntegratedCacheReadAccess<'t>,
-}
-
-#[unsafe(no_mangle)]
-pub extern "C" fn rcommunicator_backend_init(
-    cis: Box<CommunicatorInitStruct>,
-    my_proc_number: i32,
-) -> &'static mut CommunicatorBackendStruct<'static> {
-    if my_proc_number < 0 {
-        panic!("cannot attach to communicator shared memory with procnumber {my_proc_number}");
-    }
-
-    let integrated_cache = Box::leak(Box::new(cis.integrated_cache_init_struct.backend_init()));
-
-    let bs: &'static mut CommunicatorBackendStruct =
-        Box::leak(Box::new(CommunicatorBackendStruct {
-            my_proc_number,
-            neon_request_slots: cis.neon_request_slots,
-
-            submission_pipe_write_fd: cis.submission_pipe_write_fd,
-            pending_cache_read_op: None,
-
-            integrated_cache,
-        }));
-    bs
-}
-
-/// Start a request. You can poll for its completion and get the result by
-/// calling bcomm_poll_dbsize_request_completion(). The communicator will wake
-/// us up by setting our process latch, so to wait for the completion, wait on
-/// the latch and call bcomm_poll_dbsize_request_completion() every time the
-/// latch is set.
-///
-/// Safety: The C caller must ensure that the references are valid.
-/// The requested slot must be free, or this panics.
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_start_io_request(
-    bs: &'_ mut CommunicatorBackendStruct,
-    slot_idx: i32,
-    request: &NeonIORequest,
-    immediate_result_ptr: &mut NeonIOResult,
-) -> i32 {
-    assert!(bs.pending_cache_read_op.is_none());
-
-    // Check if the request can be satisfied from the cache first
-    if let NeonIORequest::RelSize(req) = request {
-        if let Some(nblocks) = bs.integrated_cache.get_rel_size(&req.reltag()) {
-            *immediate_result_ptr = NeonIOResult::RelSize(nblocks);
-            return -1;
-        }
-    }
-
-    // Create neon request and submit it
-    bs.start_neon_io_request(slot_idx, request);
-
-    slot_idx
-}
-
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_start_get_page_v_request(
-    bs: &mut CommunicatorBackendStruct,
-    slot_idx: i32,
-    request: &NeonIORequest,
-    immediate_result_ptr: &mut CCachedGetPageVResult,
-) -> i32 {
-    let NeonIORequest::GetPageV(get_pagev_request) = request else {
-        panic!("invalid request passed to bcomm_start_get_page_v_request()");
-    };
-    assert!(matches!(request, NeonIORequest::GetPageV(_)));
-    assert!(bs.pending_cache_read_op.is_none());
-
-    // Check if the request can be satisfied from the cache first
-    let mut all_cached = true;
-    let mut read_op = bs.integrated_cache.start_read_op();
-    for i in 0..get_pagev_request.nblocks {
-        if let Some(cache_block) = read_op.get_page(
-            &get_pagev_request.reltag(),
-            get_pagev_request.block_number + i as u32,
-        ) {
-            immediate_result_ptr.cache_block_numbers[i as usize] = cache_block;
-        } else {
-            // not found in cache
-            all_cached = false;
-            break;
-        }
-    }
-    if all_cached {
-        bs.pending_cache_read_op = Some(read_op);
-        return -1;
-    }
-
-    // Create neon request and submit it
-    bs.start_neon_io_request(slot_idx, request);
-
-    slot_idx
-}
-
-/// Check if a request has completed. Returns:
-///
-/// -1 if the request is still being processed
-/// 0 on success
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_poll_request_completion(
-    bs: &mut CommunicatorBackendStruct,
-    request_slot_idx: u32,
-    result_p: &mut NeonIOResult,
-) -> i32 {
-    match bs.neon_request_slots[request_slot_idx as usize].try_get_result() {
-        None => -1, // still processing
-        Some(result) => {
-            *result_p = result;
-            0
-        }
-    }
-}
-
-/// Check if a request has completed. Returns:
-///
-/// 'false' if the slot is Idle. The backend process has ownership.
-/// 'true' if the slot is busy, and should be polled for result.
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_get_request_slot_status(
-    bs: &mut CommunicatorBackendStruct,
-    request_slot_idx: u32,
-) -> bool {
-    use crate::backend_comms::NeonIORequestSlotState;
-    match bs.neon_request_slots[request_slot_idx as usize].get_state() {
-        NeonIORequestSlotState::Idle => false,
-        NeonIORequestSlotState::Filling => {
-            // 'false' would be the right result here. However, this
-            // is a very transient state. The C code should never
-            // leave a slot in this state, so if it sees that,
-            // something's gone wrong and it's not clear what to do
-            // with it.
-            panic!("unexpected Filling state in request slot {request_slot_idx}");
-        }
-        NeonIORequestSlotState::Submitted => true,
-        NeonIORequestSlotState::Processing => true,
-        NeonIORequestSlotState::Completed => true,
-    }
-}
-
-// LFC functions
-
-/// Finish a local file cache read
-///
-//
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_finish_cache_read(bs: &mut CommunicatorBackendStruct) -> bool {
-    if let Some(op) = bs.pending_cache_read_op.take() {
-        op.finish()
-    } else {
-        panic!("bcomm_finish_cache_read() called with no cached read pending");
-    }
-}
-
-/// Check if LFC contains the given buffer, and update its last-written LSN if not.
-///
-/// This is used in WAL replay in read replica, to skip updating pages that are
-/// not in cache.
-#[unsafe(no_mangle)]
-pub extern "C" fn bcomm_update_lw_lsn_for_block_if_not_cached(
-    bs: &mut CommunicatorBackendStruct,
-    spc_oid: COid,
-    db_oid: COid,
-    rel_number: u32,
-    fork_number: u8,
-    block_number: u32,
-    lsn: CLsn,
-) -> bool {
-    bs.integrated_cache.update_lw_lsn_for_block_if_not_cached(
-        &pageserver_page_api::RelTag {
-            spcnode: spc_oid,
-            dbnode: db_oid,
-            relnode: rel_number,
-            forknum: fork_number,
-        },
-        block_number,
-        Lsn(lsn),
-    )
-}
-
-#[repr(C)]
-#[derive(Clone, Debug)]
-pub struct FileCacheIterator {
-    next_bucket: u64,
-
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-}
-
-/// Iterate over LFC contents
-#[allow(clippy::missing_safety_doc)]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn bcomm_cache_iterate_begin(
-    _bs: &mut CommunicatorBackendStruct,
-    iter: *mut FileCacheIterator,
-) {
-    unsafe { (*iter).next_bucket = 0 };
-}
-
-#[allow(clippy::missing_safety_doc)]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn bcomm_cache_iterate_next(
-    bs: &mut CommunicatorBackendStruct,
-    iter: *mut FileCacheIterator,
-) -> bool {
-    use crate::integrated_cache::GetBucketResult;
-    loop {
-        let next_bucket = unsafe { (*iter).next_bucket } as usize;
-        match bs.integrated_cache.get_bucket(next_bucket) {
-            GetBucketResult::Occupied(rel, blk) => {
-                unsafe {
-                    (*iter).spc_oid = rel.spcnode;
-                    (*iter).db_oid = rel.dbnode;
-                    (*iter).rel_number = rel.relnode;
-                    (*iter).fork_number = rel.forknum;
-                    (*iter).block_number = blk;
-
-                    (*iter).next_bucket += 1;
-                }
-                break true;
-            }
-            GetBucketResult::Vacant => {
-                unsafe {
-                    (*iter).next_bucket += 1;
-                }
-                continue;
-            }
-            GetBucketResult::OutOfBounds => {
-                break false;
-            }
-        }
-    }
-}
-
-#[allow(clippy::missing_safety_doc)]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn bcomm_cache_get_num_pages_used(bs: &mut CommunicatorBackendStruct) -> u64 {
-    bs.integrated_cache.get_num_buckets_in_use() as u64
-}
-
-impl<'t> CommunicatorBackendStruct<'t> {
-    /// The slot must be free, or this panics.
-    pub(crate) fn start_neon_io_request(&mut self, request_slot_idx: i32, request: &NeonIORequest) {
-        let my_proc_number = self.my_proc_number;
-
-        self.neon_request_slots[request_slot_idx as usize].submit_request(request, my_proc_number);
-
-        // Tell the communicator about it
-        self.notify_about_request(request_slot_idx);
-    }
-
-    /// Send a wakeup to the communicator process
-    fn notify_about_request(self: &CommunicatorBackendStruct<'t>, request_slot_idx: i32) {
-        // wake up communicator by writing the idx to the submission pipe
-        //
-
-        // This can block, if the pipe is full. That should be very rare,
-        // because the communicator tries hard to drain the pipe to prevent
-        // that. Also, there's a natural upper bound on how many wakeups can be
-        // queued up: there is only a limited number of request slots for each
-        // backend.
-        //
-        // If it does block very briefly, that's not too serious.
-        let idxbuf = request_slot_idx.to_ne_bytes();
-
-        let _res = nix::unistd::write(&self.submission_pipe_write_fd, &idxbuf);
-        // FIXME: check result, return any errors
-    }
-}

pgxn/neon/communicator/src/file_cache.rs

@@ -1,299 +0,0 @@
-//! Implement the "low-level" parts of the file cache.
-//!
-//! This module just deals with reading and writing the file, and keeping track
-//! which blocks in the cache file are in use and which are free. The "high
-//! level" parts of tracking which block in the cache file corresponds to which
-//! relation block is handled in 'integrated_cache' instead.
-//!
-//! This module is only used to access the file from the communicator
-//! process. The backend processes *also* read the file (and sometimes also
-//! write it? ), but the backends use direct C library calls for that.
-use std::fs::File;
-use std::os::unix::fs::FileExt;
-use std::path::{Path, PathBuf};
-use std::sync::Arc;
-use std::sync::Mutex;
-use std::sync::atomic::{AtomicU64, Ordering};
-
-use measured::metric;
-use measured::metric::MetricEncoding;
-use measured::metric::gauge::GaugeState;
-use measured::{Gauge, MetricGroup};
-
-use crate::BLCKSZ;
-
-use tokio::task::spawn_blocking;
-
-pub type CacheBlock = u64;
-
-pub const INVALID_CACHE_BLOCK: CacheBlock = u64::MAX;
-
-pub struct FileCache {
-    file: Arc<File>,
-    free_list: Mutex<FreeList>,
-
-	/// The true number of writable blocks within the LFC file.
-	///
-	/// The `max_blocks` field of `FreeList` isn't sufficient once holes are
-	/// punched, so we track this manually.
-	pub size: AtomicU64,
-
-	/// The path to the LFC file.
-	///
-	/// The `fiemap-rs` library doesn't expose any way to issue a FIEMAP ioctl
-	/// on an existing file descriptor, so we have to save the path.
-	path: PathBuf,
-
-    metrics: FileCacheMetricGroup,
-}
-
-#[derive(MetricGroup)]
-#[metric(new())]
-struct FileCacheMetricGroup {
-    /// Local File Cache size in 8KiB blocks
-    max_blocks: Gauge,
-
-    /// Number of free 8KiB blocks in Local File Cache
-    num_free_blocks: Gauge,
-}
-
-// TODO: We keep track of all free blocks in this vec. That doesn't really scale.
-// Idea: when free_blocks fills up with more than 1024 entries, write them all to
-// one block on disk.
-#[derive(Debug)]
-struct FreeList {
-    next_free_block: CacheBlock,
-    max_blocks: u64,
-    free_blocks: Vec<CacheBlock>,
-}
-
-impl FileCache {
-    pub fn new(file_cache_path: &Path, mut initial_size: u64) -> Result<FileCache, std::io::Error> {
-        if initial_size < 100 {
-            tracing::warn!(
-                "min size for file cache is 100 blocks, {} requested",
-                initial_size
-            );
-            initial_size = 100;
-        }
-
-        let file = std::fs::OpenOptions::new()
-            .read(true)
-            .write(true)
-            .truncate(true)
-            .create(true)
-            .open(file_cache_path)?;
-
-        Ok(FileCache {
-            file: Arc::new(file),
-			size: initial_size.into(),
-            free_list: Mutex::new(FreeList {
-                next_free_block: 0,
-                max_blocks: initial_size,
-                free_blocks: Vec::new(),
-            }),
-			path: file_cache_path.to_path_buf(),
-            metrics: FileCacheMetricGroup::new(),
-        })
-    }
-
-    pub async fn read_block(
-        &self,
-        cache_block: CacheBlock,
-        mut dst: impl uring_common::buf::IoBufMut + Send + Sync,
-    ) -> Result<(), std::io::Error> {
-        assert!(dst.bytes_total() == BLCKSZ);
-        let file = self.file.clone();
-
-        let dst_ref = unsafe { std::slice::from_raw_parts_mut(dst.stable_mut_ptr(), BLCKSZ) };
-
-        spawn_blocking(move || file.read_exact_at(dst_ref, cache_block * BLCKSZ as u64)).await??;
-        Ok(())
-    }
-
-    pub async fn write_block(
-        &self,
-        cache_block: CacheBlock,
-        src: impl uring_common::buf::IoBuf + Send + Sync,
-    ) -> Result<(), std::io::Error> {
-        assert!(src.bytes_init() == BLCKSZ);
-        let file = self.file.clone();
-
-        let src_ref = unsafe { std::slice::from_raw_parts(src.stable_ptr(), BLCKSZ) };
-
-        spawn_blocking(move || file.write_all_at(src_ref, cache_block * BLCKSZ as u64)).await??;
-
-        Ok(())
-    }
-
-	/// Allocate a block within the LFC file for use by the LFC.	
-    pub fn alloc_block(&self) -> Option<CacheBlock> {		
-        let mut free_list = self.free_list.lock().unwrap();
-        if let Some(x) = free_list.free_blocks.pop() {
-            return Some(x);
-        }
-        if free_list.next_free_block < free_list.max_blocks {
-            let result = free_list.next_free_block;
-            free_list.next_free_block += 1;
-            return Some(result);
-        }
-        None
-    }
-
-	/// Mark a block used by the LFC as free for allocation.
-    pub fn dealloc_block(&self, cache_block: CacheBlock) {
-        let mut free_list = self.free_list.lock().unwrap();
-        free_list.free_blocks.push(cache_block);
-    }
-
-	/// Attempt to let the filesystem reclaim `num_blocks` of free blocks within the LFC.
-	/// Returns the number of blocks not reclaimed by the filesystem.
-	pub fn reclaim_blocks(&self, num_blocks: u64) -> u64 {
-		let mut free_list = self.free_list.lock().unwrap();
-
-		// Try to limit the maximum first so that we can shrink without doing any I/O
-		let unused_space = num_blocks.min(free_list.max_blocks - free_list.next_free_block);
-		free_list.max_blocks -= unused_space;
-		self.size.fetch_sub(unused_space, Ordering::Relaxed);
-
-		let punched = (free_list.free_blocks.len() as u64).min(num_blocks - unused_space);
-		for _ in 0..punched {
-			self.punch_block(free_list.free_blocks.pop().unwrap());
-		}
-		
-		num_blocks - unused_space - punched
-	}
-	
-	// "Delete" a block via fallocate's hole punching feature.
-	// TODO(quantumish): possibly implement some batching? lots of syscalls...
-	// unfortunately should be at odds with our access pattern as entries in the hashmap
-	// should have no correlation with the location of blocks in the actual LFC file.
-
-	/// "Un-punch" a block by re-allocating it with `fallocate` and update LFC size.
-	fn unpunch_block(&self, block: CacheBlock) {
-		use nix::fcntl as nix;
-		self.size.fetch_add(1, Ordering::Relaxed);
-		if let Err(e) = nix::fallocate(
-			self.file.clone(),
-			nix::FallocateFlags::FALLOC_FL_ZERO_RANGE
-				.union(nix::FallocateFlags::FALLOC_FL_KEEP_SIZE),
-			(block as usize * BLCKSZ) as libc::off_t,
-			BLCKSZ as libc::off_t
-		) {
-			tracing::error!("failed to un-punch hole in LFC at {block}: {e}");
-			return;
-		}
-	}
-
-	/// "Punch" a block out of the LFC file by using `fallocate` and update LFC size.
-	pub fn punch_block(&self, block: CacheBlock) {
-		use nix::fcntl as nix;
-		self.size.fetch_sub(1, Ordering::Relaxed);
-		if let Err(e) = nix::fallocate(
-			self.file.clone(),
-			nix::FallocateFlags::FALLOC_FL_PUNCH_HOLE
-				.union(nix::FallocateFlags::FALLOC_FL_KEEP_SIZE),
-			(block as usize * BLCKSZ) as libc::off_t,
-			BLCKSZ as libc::off_t
-		) {
-			tracing::error!("failed to punch hole in LFC at {block}: {e}");
-			return;
-		}
-	}
-
-	/// Attempt to unpunch `num_blocks` of previously hole-punched blocks.
-	///
-	/// Similarly named to `unpunch_block` but does not punch a series of blocks in a row.
-	/// Instead uses FIEMAP ioctl to locate holes in the file and unpunch them!
-	#[cfg(target_os = "linux")]
-	pub fn unpunch_blocks(&self, num_blocks: u64) -> u64 {
-		use itertools::Itertools;
-		let mut pushed = 0;
-		let mut free_list = self.free_list.lock().unwrap();
-		let res = fiemap::fiemap(self.path.as_path()).unwrap();
-		for (prev, cur) in res.map(|x| x.unwrap()).tuple_windows() {
-			if (prev.fe_logical + prev.fe_length) < cur.fe_logical {
-				let mut end = prev.fe_logical + prev.fe_length;
-				while end < cur.fe_logical {					
-					free_list.free_blocks.push(end / BLCKSZ as u64);
-					self.unpunch_block(end / BLCKSZ as u64);
-					pushed += 1;
-					if pushed == num_blocks {
-						return 0;
-					}
-					end += BLCKSZ as u64;
-				}
-			}
-		}
-		num_blocks - pushed
-	}
-	
-	/// Attempt to unpunch `num_blocks` of previously hole-punched blocks.
-	///
-	/// Much more expensive than the Linux variant as each hole must be located
-	/// by a separate call to `lseek`.
-	///
-	/// FIXME: Sometimes this function provides inaccurate counts of the number
-	/// of holes within a file. Whether we need this function at all is unclear,
-	/// as seemingly this part of the codebase only targets a system with ext4?
-	#[cfg(target_os = "macos")]
-	pub fn unpunch_blocks(&self, num_blocks: u64) -> u64 {
-		use nix::unistd as nix;
-		let mut free_list = self.free_list.lock().unwrap();
-		let num_bytes = (free_list.next_free_block * BLOCKSZ) as i64;
-		let mut cur_pos = 0;
-		let mut pushed = 0;
-		while cur_pos < num_bytes {
-			let res = nix::lseek(
-				file.clone(),
-				cur_pos,
-				nix::Whence::SeekHole
-			).unwrap();
-			if res >= num_bytes {
-				break;
-			}
-			self.unpunch_block(res);
-			free_list.free_blocks.push(res);
-			pushed += 1;
-			if pushed == num_blocks {
-				return 0;
-			}
-			cur_pos = res + BLOCKSZ as i64;
-		}
-		num_blocks - pushed
-	}
-
-	/// Physically grows the file and expands the freelist.
-	pub fn grow(&self, num_blocks: u64) {
-		let mut free_list = self.free_list.lock().unwrap();
-		self.size.fetch_add(num_blocks, Ordering::Relaxed);
-		free_list.max_blocks += num_blocks;
-	}
-
-	/// Returns number of blocks in the remaining space.
-	pub fn free_space(&self) -> u64 {
-		let free_list = self.free_list.lock().unwrap();
-		let slab = free_list.max_blocks - free_list.next_free_block.min(free_list.max_blocks);
-		let fragments = free_list.free_blocks.len() as u64;
-		slab + fragments
-	}
-}
-
-impl<T: metric::group::Encoding> MetricGroup<T> for FileCache
-where
-    GaugeState: MetricEncoding<T>,
-{
-    fn collect_group_into(&self, enc: &mut T) -> Result<(), <T as metric::group::Encoding>::Err> {
-        // Update the gauges with fresh values first
-        {
-            let free_list = self.free_list.lock().unwrap();
-            self.metrics.max_blocks.set(free_list.max_blocks as i64);
-
-            let total_free_blocks: i64 = free_list.free_blocks.len() as i64
-                + (free_list.max_blocks as i64 - free_list.next_free_block as i64);
-            self.metrics.num_free_blocks.set(total_free_blocks);
-        }
-
-        self.metrics.collect_group_into(enc)
-    }
-}

pgxn/neon/communicator/src/global_allocator.rs

@@ -1,107 +0,0 @@
-//! Global allocator, for tracking memory usage of the Rust parts
-//!
-//! Postgres is designed to handle allocation failure (ie. malloc() returning NULL) gracefully.  It
-//! rolls backs the transaction and gives the user an "ERROR: out of memory" error. Rust code
-//! however panics if an allocation fails. We don't want that to ever happen, because an unhandled
-//! panic leads to Postgres crash and restart. Our strategy is to pre-allocate a large enough chunk
-//! of memory for use by the Rust code, so that the allocations never fail.
-//!
-//! To pick the size for the pre-allocated chunk, we have a metric to track the high watermark
-//! memory usage of all the Rust allocations in total.
-//!
-//! TODO:
-//!
-//! - Currently we just export the metrics. Actual allocations are still just passed through to
-//!   the system allocator.
-//! - Take padding etc. overhead into account
-
-use std::alloc::{GlobalAlloc, Layout, System};
-use std::sync::atomic::{AtomicU64, AtomicUsize, Ordering};
-
-use measured::metric;
-use measured::metric::MetricEncoding;
-use measured::metric::gauge::GaugeState;
-use measured::{Gauge, MetricGroup};
-
-pub(crate) struct MyAllocator {
-    allocations: AtomicU64,
-    deallocations: AtomicU64,
-
-    allocated: AtomicUsize,
-    high: AtomicUsize,
-}
-
-#[derive(MetricGroup)]
-#[metric(new())]
-struct MyAllocatorMetricGroup {
-    /// Number of allocations in Rust code
-    communicator_mem_allocations: Gauge,
-
-    /// Number of deallocations in Rust code
-    communicator_mem_deallocations: Gauge,
-
-    /// Bytes currently allocated
-    communicator_mem_allocated: Gauge,
-
-    /// High watermark of allocated bytes
-    communicator_mem_high: Gauge,
-}
-
-unsafe impl GlobalAlloc for MyAllocator {
-    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
-        self.allocations.fetch_add(1, Ordering::Relaxed);
-        let mut allocated = self.allocated.fetch_add(layout.size(), Ordering::Relaxed);
-        allocated += layout.size();
-        self.high.fetch_max(allocated, Ordering::Relaxed);
-        unsafe { System.alloc(layout) }
-    }
-
-    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
-        self.deallocations.fetch_add(1, Ordering::Relaxed);
-        self.allocated.fetch_sub(layout.size(), Ordering::Relaxed);
-        unsafe { System.dealloc(ptr, layout) }
-    }
-}
-
-#[global_allocator]
-static GLOBAL: MyAllocator = MyAllocator {
-    allocations: AtomicU64::new(0),
-    deallocations: AtomicU64::new(0),
-    allocated: AtomicUsize::new(0),
-    high: AtomicUsize::new(0),
-};
-
-pub(crate) struct MyAllocatorCollector {
-    metrics: MyAllocatorMetricGroup,
-}
-
-impl MyAllocatorCollector {
-    pub(crate) fn new() -> Self {
-        Self {
-            metrics: MyAllocatorMetricGroup::new(),
-        }
-    }
-}
-
-impl<T: metric::group::Encoding> MetricGroup<T> for MyAllocatorCollector
-where
-    GaugeState: MetricEncoding<T>,
-{
-    fn collect_group_into(&self, enc: &mut T) -> Result<(), <T as metric::group::Encoding>::Err> {
-        // Update the gauges with fresh values first
-        self.metrics
-            .communicator_mem_allocations
-            .set(GLOBAL.allocations.load(Ordering::Relaxed) as i64);
-        self.metrics
-            .communicator_mem_deallocations
-            .set(GLOBAL.allocations.load(Ordering::Relaxed) as i64);
-        self.metrics
-            .communicator_mem_allocated
-            .set(GLOBAL.allocated.load(Ordering::Relaxed) as i64);
-        self.metrics
-            .communicator_mem_high
-            .set(GLOBAL.high.load(Ordering::Relaxed) as i64);
-
-        self.metrics.collect_group_into(enc)
-    }
-}

pgxn/neon/communicator/src/init.rs

@@ -1,166 +0,0 @@
-//! Initialization functions. These are executed in the postmaster process,
-//! at different stages of server startup.
-//!
-//!
-//! Communicator initialization steps:
-//!
-//! 1. At postmaster startup, before shared memory is allocated,
-//!    rcommunicator_shmem_size() is called to get the amount of
-//!    shared memory that this module needs.
-//!
-//! 2. Later, after the shared memory has been allocated,
-//!    rcommunicator_shmem_init() is called to initialize the shmem
-//!    area.
-//!
-//! Per process initialization:
-//!
-//! When a backend process starts up, it calls rcommunicator_backend_init().
-//! In the communicator worker process, other functions are called, see
-//! `worker_process` module.
-
-use std::ffi::c_int;
-use std::mem;
-use std::mem::MaybeUninit;
-use std::os::fd::OwnedFd;
-
-use crate::backend_comms::NeonIORequestSlot;
-use crate::integrated_cache::IntegratedCacheInitStruct;
-
-/// This struct is created in the postmaster process, and inherited to
-/// the communicator process and all backend processes through fork()
-#[repr(C)]
-pub struct CommunicatorInitStruct {
-    pub submission_pipe_read_fd: OwnedFd,
-    pub submission_pipe_write_fd: OwnedFd,
-
-    // Shared memory data structures
-    pub num_neon_request_slots: u32,
-
-    pub neon_request_slots: &'static [NeonIORequestSlot],
-
-    pub integrated_cache_init_struct: IntegratedCacheInitStruct<'static>,
-}
-
-impl std::fmt::Debug for CommunicatorInitStruct {
-    fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
-        fmt.debug_struct("CommunicatorInitStruct")
-            .field("submission_pipe_read_fd", &self.submission_pipe_read_fd)
-            .field("submission_pipe_write_fd", &self.submission_pipe_write_fd)
-            .field("num_neon_request_slots", &self.num_neon_request_slots)
-            .field("neon_request_slots length", &self.neon_request_slots.len())
-            .finish()
-    }
-}
-
-#[unsafe(no_mangle)]
-pub extern "C" fn rcommunicator_shmem_size(num_neon_request_slots: u32) -> u64 {
-    let mut size = 0;
-
-    size += mem::size_of::<NeonIORequestSlot>() * num_neon_request_slots as usize;
-
-    // For integrated_cache's Allocator. TODO: make this adjustable
-    size += IntegratedCacheInitStruct::shmem_size();
-
-    size as u64
-}
-
-/// Initialize the shared memory segment. Returns a backend-private
-/// struct, which will be inherited by backend processes through fork
-#[unsafe(no_mangle)]
-pub extern "C" fn rcommunicator_shmem_init(
-    submission_pipe_read_fd: c_int,
-    submission_pipe_write_fd: c_int,
-    num_neon_request_slots: u32,
-    shmem_area_ptr: *mut MaybeUninit<u8>,
-    shmem_area_len: u64,
-    initial_file_cache_size: u64,
-    max_file_cache_size: u64,
-) -> &'static mut CommunicatorInitStruct {
-    let shmem_area: &'static mut [MaybeUninit<u8>] =
-        unsafe { std::slice::from_raw_parts_mut(shmem_area_ptr, shmem_area_len as usize) };
-
-    let (neon_request_slots, remaining_area) =
-        alloc_array_from_slice::<NeonIORequestSlot>(shmem_area, num_neon_request_slots as usize);
-
-    for slot in neon_request_slots.iter_mut() {
-        slot.write(NeonIORequestSlot::default());
-    }
-
-    // 'neon_request_slots' is initialized now. (MaybeUninit::slice_assume_init_mut() is nightly-only
-    // as of this writing.)
-    let neon_request_slots = unsafe {
-        std::mem::transmute::<&mut [MaybeUninit<NeonIORequestSlot>], &mut [NeonIORequestSlot]>(
-            neon_request_slots,
-        )
-    };
-
-    // Give the rest of the area to the integrated cache
-    let integrated_cache_init_struct = IntegratedCacheInitStruct::shmem_init(
-        remaining_area,
-        initial_file_cache_size,
-        max_file_cache_size,
-    );
-
-    let (submission_pipe_read_fd, submission_pipe_write_fd) = unsafe {
-        use std::os::fd::FromRawFd;
-        (
-            OwnedFd::from_raw_fd(submission_pipe_read_fd),
-            OwnedFd::from_raw_fd(submission_pipe_write_fd),
-        )
-    };
-
-    let cis: &'static mut CommunicatorInitStruct = Box::leak(Box::new(CommunicatorInitStruct {
-        submission_pipe_read_fd,
-        submission_pipe_write_fd,
-
-        num_neon_request_slots,
-        neon_request_slots,
-
-        integrated_cache_init_struct,
-    }));
-
-    cis
-}
-
-pub fn alloc_from_slice<T>(
-    area: &mut [MaybeUninit<u8>],
-) -> (&mut MaybeUninit<T>, &mut [MaybeUninit<u8>]) {
-    let layout = std::alloc::Layout::new::<T>();
-
-    let area_start = area.as_mut_ptr();
-
-    // pad to satisfy alignment requirements
-    let padding = area_start.align_offset(layout.align());
-    if padding + layout.size() > area.len() {
-        panic!("out of memory");
-    }
-    let area = &mut area[padding..];
-    let (result_area, remain) = area.split_at_mut(layout.size());
-
-    let result_ptr: *mut MaybeUninit<T> = result_area.as_mut_ptr().cast();
-    let result = unsafe { result_ptr.as_mut().unwrap() };
-
-    (result, remain)
-}
-
-pub fn alloc_array_from_slice<T>(
-    area: &mut [MaybeUninit<u8>],
-    len: usize,
-) -> (&mut [MaybeUninit<T>], &mut [MaybeUninit<u8>]) {
-    let layout = std::alloc::Layout::new::<T>();
-
-    let area_start = area.as_mut_ptr();
-
-    // pad to satisfy alignment requirements
-    let padding = area_start.align_offset(layout.align());
-    if padding + layout.size() * len > area.len() {
-        panic!("out of memory");
-    }
-    let area = &mut area[padding..];
-    let (result_area, remain) = area.split_at_mut(layout.size() * len);
-
-    let result_ptr: *mut MaybeUninit<T> = result_area.as_mut_ptr().cast();
-    let result = unsafe { std::slice::from_raw_parts_mut(result_ptr.as_mut().unwrap(), len) };
-
-    (result, remain)
-}

pgxn/neon/communicator/src/lib.rs

@@ -1,29 +1,5 @@
-//! Three main parts:
-//! - async tokio communicator core, which receives requests and processes them.
-//! - Main loop and requests queues, which routes requests from backends to the core
-//! - the per-backend glue code, which submits requests
-
-mod backend_comms;
-
-// mark this 'pub', because these functions are called from C code. Otherwise, the compiler
-// complains about a bunch of structs and enum variants being unused, because it thinkgs
-// the functions that use them are never called. There are some C-callable functions in
-// other modules too, but marking this as pub is currently enough to silence the warnings
-//
-// TODO: perhaps collect *all* the extern "C" functions to one module?
-pub mod backend_interface;
-
-mod file_cache;
-mod init;
-mod integrated_cache;
-mod neon_request;
 mod worker_process;
 
-mod global_allocator;
-
 /// Name of the Unix Domain Socket that serves the metrics, and other APIs in the
 /// future. This is within the Postgres data directory.
 const NEON_COMMUNICATOR_SOCKET_NAME: &str = "neon-communicator.socket";
-
-// FIXME: get this from postgres headers somehow
-pub const BLCKSZ: usize = 8192;

pgxn/neon/communicator/src/neon_request.rs

@@ -1,466 +0,0 @@
-// Definitions of some core PostgreSQL datatypes.
-
-/// XLogRecPtr is defined in "access/xlogdefs.h" as:
-///
-/// ```
-/// typedef uint64 XLogRecPtr;
-/// ```
-/// cbindgen:no-export
-pub type XLogRecPtr = u64;
-
-pub type CLsn = XLogRecPtr;
-pub type COid = u32;
-
-// This conveniently matches PG_IOV_MAX
-pub const MAX_GETPAGEV_PAGES: usize = 32;
-
-pub const INVALID_BLOCK_NUMBER: u32 = u32::MAX;
-
-use std::ffi::CStr;
-
-use pageserver_page_api::{self as page_api, SlruKind};
-
-/// Request from a Postgres backend to the communicator process
-#[allow(clippy::large_enum_variant)]
-#[repr(C)]
-#[derive(Copy, Clone, Debug, strum_macros::EnumDiscriminants)]
-#[strum_discriminants(derive(measured::FixedCardinalityLabel))]
-pub enum NeonIORequest {
-    Empty,
-
-    // Read requests. These are C-friendly variants of the corresponding structs in
-    // pageserver_page_api.
-    RelSize(CRelSizeRequest),
-    GetPageV(CGetPageVRequest),
-    ReadSlruSegment(CReadSlruSegmentRequest),
-    PrefetchV(CPrefetchVRequest),
-    DbSize(CDbSizeRequest),
-
-    /// This is like GetPageV, but bypasses the LFC and allows specifiying the
-    /// request LSNs directly. For debugging purposes only.
-    GetPageVUncached(CGetPageVUncachedRequest),
-
-    // Write requests. These are needed to keep the relation size cache and LFC up-to-date.
-    // They are not sent to the pageserver.
-    WritePage(CWritePageRequest),
-    RelExtend(CRelExtendRequest),
-    RelZeroExtend(CRelZeroExtendRequest),
-    RelCreate(CRelCreateRequest),
-    RelTruncate(CRelTruncateRequest),
-    RelUnlink(CRelUnlinkRequest),
-
-    // Other requests
-    UpdateCachedRelSize(CUpdateCachedRelSizeRequest),
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub enum NeonIOResult {
-    Empty,
-    /// InvalidBlockNumber == 0xffffffff means "rel does not exist"
-    RelSize(u32),
-
-    /// the result pages are written to the shared memory addresses given in the request
-    GetPageV,
-    /// The result is written to the file, path to which is provided
-    /// in the request. The [`u64`] value here is the number of blocks.
-    ReadSlruSegment(u64),
-
-    /// A prefetch request returns as soon as the request has been received by the communicator.
-    /// It is processed in the background.
-    PrefetchVLaunched,
-
-    DbSize(u64),
-
-    // FIXME design compact error codes. Can't easily pass a string or other dynamic data.
-    // currently, this is 'errno'
-    Error(i32),
-
-    Aborted,
-
-    /// used for all write requests
-    WriteOK,
-}
-
-impl NeonIORequest {
-    /// All requests include a unique request ID, which can be used to trace the execution
-    /// of a request all the way to the pageservers. The request ID needs to be unique
-    /// within the lifetime of the Postgres instance (but not across servers or across
-    /// restarts of the same server).
-    pub fn request_id(&self) -> u64 {
-        use NeonIORequest::*;
-        match self {
-            Empty => 0,
-            RelSize(req) => req.request_id,
-            GetPageV(req) => req.request_id,
-            GetPageVUncached(req) => req.request_id,
-            ReadSlruSegment(req) => req.request_id,
-            PrefetchV(req) => req.request_id,
-            DbSize(req) => req.request_id,
-            WritePage(req) => req.request_id,
-            RelExtend(req) => req.request_id,
-            RelZeroExtend(req) => req.request_id,
-            RelCreate(req) => req.request_id,
-            RelTruncate(req) => req.request_id,
-            RelUnlink(req) => req.request_id,
-            UpdateCachedRelSize(req) => req.request_id,
-        }
-    }
-}
-
-/// Special quick result to a CGetPageVRequest request, indicating that the
-/// the requested pages are present in the local file cache. The backend can
-/// read the blocks directly from the given LFC blocks.
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CCachedGetPageVResult {
-    pub cache_block_numbers: [u64; MAX_GETPAGEV_PAGES],
-}
-
-/// ShmemBuf represents a buffer in shared memory.
-///
-/// SAFETY: The pointer must point to an area in shared memory. The functions allow you to liberally
-/// get a mutable pointer to the contents; it is the caller's responsibility to ensure that you
-/// don't access a buffer that's you're not allowed to. Inappropriate access to the buffer doesn't
-/// violate Rust's safety semantics, but it will mess up and crash Postgres.
-///
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct ShmemBuf {
-    // Pointer to where the result is written or where to read from. Must point into a buffer in shared memory!
-    pub ptr: *mut u8,
-}
-
-unsafe impl Send for ShmemBuf {}
-unsafe impl Sync for ShmemBuf {}
-
-unsafe impl uring_common::buf::IoBuf for ShmemBuf {
-    fn stable_ptr(&self) -> *const u8 {
-        self.ptr
-    }
-
-    fn bytes_init(&self) -> usize {
-        crate::BLCKSZ
-    }
-
-    fn bytes_total(&self) -> usize {
-        crate::BLCKSZ
-    }
-}
-
-unsafe impl uring_common::buf::IoBufMut for ShmemBuf {
-    fn stable_mut_ptr(&mut self) -> *mut u8 {
-        self.ptr
-    }
-
-    unsafe fn set_init(&mut self, pos: usize) {
-        if pos > crate::BLCKSZ {
-            panic!(
-                "set_init called past end of buffer, pos {}, buffer size {}",
-                pos,
-                crate::BLCKSZ
-            );
-        }
-    }
-}
-
-impl ShmemBuf {
-    pub fn as_mut_ptr(&self) -> *mut u8 {
-        self.ptr
-    }
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelSizeRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub allow_missing: bool,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CGetPageVRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub nblocks: u8,
-
-    // These fields define where the result is written. Must point into a buffer in shared memory!
-    pub dest: [ShmemBuf; MAX_GETPAGEV_PAGES],
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CGetPageVUncachedRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub nblocks: u8,
-
-    pub request_lsn: CLsn,
-    pub not_modified_since: CLsn,
-
-    // These fields define where the result is written. Must point into a buffer in shared memory!
-    pub dest: [ShmemBuf; MAX_GETPAGEV_PAGES],
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CReadSlruSegmentRequest {
-    pub request_id: u64,
-    pub slru_kind: SlruKind,
-    pub segment_number: u32,
-    pub request_lsn: CLsn,
-    /// Must be a null-terminated C string containing the file path
-    /// where the communicator will write the SLRU segment.
-    pub destination_file_path: ShmemBuf,
-}
-
-impl CReadSlruSegmentRequest {
-    /// Returns the file path where the communicator will write the
-    /// SLRU segment.
-    pub(crate) fn destination_file_path(&self) -> String {
-        unsafe { CStr::from_ptr(self.destination_file_path.as_mut_ptr() as *const _) }
-            .to_string_lossy()
-            .into_owned()
-    }
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CPrefetchVRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub nblocks: u8,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CDbSizeRequest {
-    pub request_id: u64,
-    pub db_oid: COid,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CWritePageRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub lsn: CLsn,
-
-    // `src` defines the new page contents. Must point into a buffer in shared memory!
-    pub src: ShmemBuf,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelExtendRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub lsn: CLsn,
-
-    // `src` defines the new page contents. Must point into a buffer in shared memory!
-    pub src: ShmemBuf,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelZeroExtendRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub block_number: u32,
-    pub nblocks: u32,
-    pub lsn: CLsn,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelCreateRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub lsn: CLsn,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelTruncateRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub nblocks: u32,
-    pub lsn: CLsn,
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CRelUnlinkRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub lsn: CLsn,
-}
-
-impl CRelSizeRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CGetPageVRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CGetPageVUncachedRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CPrefetchVRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CWritePageRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CRelExtendRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CRelZeroExtendRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CRelCreateRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CRelTruncateRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-impl CRelUnlinkRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}
-
-#[repr(C)]
-#[derive(Copy, Clone, Debug)]
-pub struct CUpdateCachedRelSizeRequest {
-    pub request_id: u64,
-    pub spc_oid: COid,
-    pub db_oid: COid,
-    pub rel_number: u32,
-    pub fork_number: u8,
-    pub nblocks: u32,
-    pub lsn: CLsn,
-}
-
-impl CUpdateCachedRelSizeRequest {
-    pub fn reltag(&self) -> page_api::RelTag {
-        page_api::RelTag {
-            spcnode: self.spc_oid,
-            dbnode: self.db_oid,
-            relnode: self.rel_number,
-            forknum: self.fork_number,
-        }
-    }
-}

pgxn/neon/communicator/src/worker_process/callbacks.rs

@@ -4,13 +4,10 @@
 //!
 //! These are called from the communicator threads! Careful what you do, most Postgres
 //! functions are not safe to call in that context.
-use utils::lsn::Lsn;
 
 #[cfg(not(test))]
 unsafe extern "C" {
-    pub fn notify_proc_unsafe(procno: std::ffi::c_int);
     pub fn callback_set_my_latch_unsafe();
-    pub fn callback_get_request_lsn_unsafe() -> crate::neon_request::CLsn;
     pub fn callback_get_lfc_metrics_unsafe() -> LfcMetrics;
 }
 
@@ -19,36 +16,20 @@ unsafe extern "C" {
 // package, but the code coverage build still builds these and tries to link with the
 // external C code.)
 #[cfg(test)]
-unsafe fn notify_proc_unsafe(_procno: std::ffi::c_int) {
-    panic!("not usable in unit tests");
-}
-#[cfg(test)]
 unsafe fn callback_set_my_latch_unsafe() {
     panic!("not usable in unit tests");
 }
 #[cfg(test)]
-unsafe fn callback_get_request_lsn_unsafe() -> crate::neon_request::CLsn {
-    panic!("not usable in unit tests");
-}
-#[cfg(test)]
 unsafe fn callback_get_lfc_metrics_unsafe() -> LfcMetrics {
     panic!("not usable in unit tests");
 }
 
 // safe wrappers
 
-pub(super) fn notify_proc(procno: std::ffi::c_int) {
-    unsafe { notify_proc_unsafe(procno) };
-}
-
 pub(super) fn callback_set_my_latch() {
     unsafe { callback_set_my_latch_unsafe() };
 }
 
-pub(super) fn get_request_lsn() -> Lsn {
-    Lsn(unsafe { callback_get_request_lsn_unsafe() })
-}
-
 pub(super) fn callback_get_lfc_metrics() -> LfcMetrics {
     unsafe { callback_get_lfc_metrics_unsafe() }
 }

pgxn/neon/communicator/src/worker_process/control_socket.rs

@@ -19,105 +19,71 @@ use http::StatusCode;
 use http::header::CONTENT_TYPE;
 
 use measured::MetricGroup;
-use measured::metric::MetricEncoding;
-use measured::metric::gauge::GaugeState;
-use measured::metric::group::Encoding;
 use measured::text::BufferedTextEncoder;
 
 use std::io::ErrorKind;
-use std::sync::Arc;
 
 use tokio::net::UnixListener;
 
 use crate::NEON_COMMUNICATOR_SOCKET_NAME;
-use crate::worker_process::lfc_metrics::LfcMetricsCollector;
 use crate::worker_process::main_loop::CommunicatorWorkerProcessStruct;
 
-enum ControlSocketState<'a> {
-    Full(&'a CommunicatorWorkerProcessStruct<'a>),
-    Legacy(LegacyControlSocketState),
-}
+impl CommunicatorWorkerProcessStruct {
+    /// Launch the listener
+    pub(crate) async fn launch_control_socket_listener(
+        &'static self,
+    ) -> Result<(), std::io::Error> {
+        use axum::routing::get;
+        let app = Router::new()
+            .route("/metrics", get(get_metrics))
+            .route("/autoscaling_metrics", get(get_autoscaling_metrics))
+            .route("/debug/panic", get(handle_debug_panic))
+            .with_state(self);
 
-struct LegacyControlSocketState {
-    pub(crate) lfc_metrics: LfcMetricsCollector,
-}
+        // If the server is restarted, there might be an old socket still
+        // lying around. Remove it first.
+        match std::fs::remove_file(NEON_COMMUNICATOR_SOCKET_NAME) {
+            Ok(()) => {
+                tracing::warn!("removed stale control socket");
+            }
+            Err(e) if e.kind() == ErrorKind::NotFound => {}
+            Err(e) => {
+                tracing::error!("could not remove stale control socket: {e:#}");
+                // Try to proceed anyway. It will likely fail below though.
+            }
+        };
+
+        // Create the unix domain socket and start listening on it
+        let listener = UnixListener::bind(NEON_COMMUNICATOR_SOCKET_NAME)?;
+
+        tokio::spawn(async {
+            tracing::info!("control socket listener spawned");
+            axum::serve(listener, app)
+                .await
+                .expect("axum::serve never returns")
+        });
 
-impl<T> MetricGroup<T> for LegacyControlSocketState
-where
-    T: Encoding,
-    GaugeState: MetricEncoding<T>,
-{
-    fn collect_group_into(&self, enc: &mut T) -> Result<(), T::Err> {
-        self.lfc_metrics.collect_group_into(enc)?;
         Ok(())
     }
 }
 
-/// Launch the listener
-pub(crate) async fn launch_listener(
-    worker: Option<&'static CommunicatorWorkerProcessStruct<'static>>,
-) -> Result<(), std::io::Error> {
-    use axum::routing::get;
-
-    let state = match worker {
-        Some(worker) => ControlSocketState::Full(worker),
-        None => ControlSocketState::Legacy(LegacyControlSocketState {
-            lfc_metrics: LfcMetricsCollector,
-        }),
-    };
-
-    let app = Router::new()
-        .route("/metrics", get(get_metrics))
-        .route("/autoscaling_metrics", get(get_autoscaling_metrics))
-        .route("/debug/panic", get(handle_debug_panic))
-        .route("/debug/dump_cache_map", get(dump_cache_map))
-        .with_state(Arc::new(state));
-
-    // If the server is restarted, there might be an old socket still
-    // lying around. Remove it first.
-    match std::fs::remove_file(NEON_COMMUNICATOR_SOCKET_NAME) {
-        Ok(()) => {
-            tracing::warn!("removed stale control socket");
-        }
-        Err(e) if e.kind() == ErrorKind::NotFound => {}
-        Err(e) => {
-            tracing::error!("could not remove stale control socket: {e:#}");
-            // Try to proceed anyway. It will likely fail below though.
-        }
-    };
-
-    // Create the unix domain socket and start listening on it
-    let listener = UnixListener::bind(NEON_COMMUNICATOR_SOCKET_NAME)?;
-
-    tokio::spawn(async {
-        tracing::info!("control socket listener spawned");
-        axum::serve(listener, app)
-            .await
-            .expect("axum::serve never returns")
-    });
-
-    Ok(())
-}
-
 /// Expose all Prometheus metrics.
-async fn get_metrics(State(state): State<Arc<ControlSocketState<'_>>>) -> Response {
-    match state.as_ref() {
-        ControlSocketState::Full(worker) => metrics_to_response(&worker).await,
-        ControlSocketState::Legacy(legacy) => metrics_to_response(&legacy).await,
-    }
+async fn get_metrics(State(state): State<&CommunicatorWorkerProcessStruct>) -> Response {
+    tracing::trace!("/metrics requested");
+    metrics_to_response(&state).await
 }
 
 /// Expose Prometheus metrics, for use by the autoscaling agent.
 ///
 /// This is a subset of all the metrics.
-async fn get_autoscaling_metrics(State(state): State<Arc<ControlSocketState<'_>>>) -> Response {
-    match state.as_ref() {
-        ControlSocketState::Full(worker) => metrics_to_response(&worker.lfc_metrics).await,
-        ControlSocketState::Legacy(legacy) => metrics_to_response(&legacy.lfc_metrics).await,
-    }
+async fn get_autoscaling_metrics(
+    State(state): State<&CommunicatorWorkerProcessStruct>,
+) -> Response {
+    tracing::trace!("/metrics requested");
+    metrics_to_response(&state.lfc_metrics).await
 }
 
-async fn handle_debug_panic(State(_state): State<Arc<ControlSocketState<'_>>>) -> Response {
+async fn handle_debug_panic(State(_state): State<&CommunicatorWorkerProcessStruct>) -> Response {
     panic!("test HTTP handler task panic");
 }
 
@@ -134,23 +100,3 @@ async fn metrics_to_response(metrics: &(dyn MetricGroup<BufferedTextEncoder> + S
         .body(Body::from(enc.finish()))
         .unwrap()
 }
-
-async fn dump_cache_map(State(state): State<Arc<ControlSocketState<'_>>>) -> Response {
-    match state.as_ref() {
-        ControlSocketState::Full(worker) => {
-            let mut buf: Vec<u8> = Vec::new();
-            worker.cache.dump_map(&mut buf);
-
-            Response::builder()
-                .status(StatusCode::OK)
-                .header(CONTENT_TYPE, "application/text")
-                .body(Body::from(buf))
-                .unwrap()
-        }
-        ControlSocketState::Legacy(_) => Response::builder()
-            .status(StatusCode::NOT_FOUND)
-            .header(CONTENT_TYPE, "application/text")
-            .body(Body::from(Vec::new()))
-            .unwrap(),
-    }
-}

pgxn/neon/communicator/src/worker_process/in_progress_ios.rs

@@ -1,95 +0,0 @@
-//! Lock table to ensure that only one IO request is in flight for a given
-//! block (or relation or database metadata) at a time
-
-use std::cmp::Eq;
-use std::hash::Hash;
-use std::sync::Arc;
-
-use tokio::sync::{Mutex, OwnedMutexGuard};
-
-use clashmap::ClashMap;
-use clashmap::Entry;
-
-use pageserver_page_api::RelTag;
-
-#[derive(Clone, Eq, Hash, PartialEq)]
-pub enum RequestInProgressKey {
-    Db(u32),
-    Rel(RelTag),
-    Block(RelTag, u32),
-}
-
-type RequestId = u64;
-
-pub type RequestInProgressTable = MutexHashMap<RequestInProgressKey, RequestId>;
-
-// more primitive locking thingie:
-
-pub struct MutexHashMap<K, V>
-where
-    K: Clone + Eq + Hash,
-{
-    lock_table: ClashMap<K, (V, Arc<Mutex<()>>)>,
-}
-
-pub struct MutexHashMapGuard<'a, K, V>
-where
-    K: Clone + Eq + Hash,
-{
-    pub key: K,
-    map: &'a MutexHashMap<K, V>,
-    mutex: Arc<Mutex<()>>,
-    _guard: OwnedMutexGuard<()>,
-}
-
-impl<'a, K, V> Drop for MutexHashMapGuard<'a, K, V>
-where
-    K: Clone + Eq + Hash,
-{
-    fn drop(&mut self) {
-        let (_old_key, old_val) = self.map.lock_table.remove(&self.key).unwrap();
-        assert!(Arc::ptr_eq(&old_val.1, &self.mutex));
-
-        // the guard will be dropped as we return
-    }
-}
-
-impl<K, V> MutexHashMap<K, V>
-where
-    K: Clone + Eq + Hash,
-    V: std::fmt::Display + Copy,
-{
-    pub fn new() -> MutexHashMap<K, V> {
-        MutexHashMap {
-            lock_table: ClashMap::new(),
-        }
-    }
-
-    pub async fn lock<'a>(&'a self, key: K, val: V) -> MutexHashMapGuard<'a, K, V> {
-        let my_mutex = Arc::new(Mutex::new(()));
-        let my_guard = Arc::clone(&my_mutex).lock_owned().await;
-
-        loop {
-            let (request_id, lock) = match self.lock_table.entry(key.clone()) {
-                Entry::Occupied(e) => {
-                    let e = e.get();
-                    (e.0, Arc::clone(&e.1))
-                }
-                Entry::Vacant(e) => {
-                    e.insert((val, Arc::clone(&my_mutex)));
-                    break;
-                }
-            };
-            tracing::info!("waiting for conflicting IO {request_id} to complete");
-            let _ = lock.lock().await;
-            tracing::info!("conflicting IO {request_id} completed");
-        }
-
-        MutexHashMapGuard {
-            key,
-            map: self,
-            mutex: my_mutex,
-            _guard: my_guard,
-        }
-    }
-}

pgxn/neon/communicator/src/worker_process/main_loop.rs

@@ -1,126 +1,34 @@
-use std::collections::HashMap;
-use std::os::fd::AsRawFd;
-use std::os::fd::OwnedFd;
-use std::path::PathBuf;
 use std::str::FromStr as _;
 
-use crate::backend_comms::NeonIORequestSlot;
-use crate::file_cache::FileCache;
-use crate::global_allocator::MyAllocatorCollector;
-use crate::init::CommunicatorInitStruct;
-use crate::integrated_cache::{CacheResult, IntegratedCacheWriteAccess};
-use crate::neon_request::{CGetPageVRequest, CGetPageVUncachedRequest, CPrefetchVRequest};
-use crate::neon_request::{INVALID_BLOCK_NUMBER, NeonIORequest, NeonIOResult};
-use crate::worker_process::control_socket;
-use crate::worker_process::in_progress_ios::{RequestInProgressKey, RequestInProgressTable};
 use crate::worker_process::lfc_metrics::LfcMetricsCollector;
-use pageserver_client_grpc::{PageserverClient, ShardSpec, ShardStripeSize};
-use pageserver_page_api as page_api;
-
-use tokio::io::AsyncReadExt;
-use tokio_pipe::PipeRead;
-use uring_common::buf::IoBuf;
 
 use measured::MetricGroup;
 use measured::metric::MetricEncoding;
-use measured::metric::counter::CounterState;
 use measured::metric::gauge::GaugeState;
 use measured::metric::group::Encoding;
-use measured::{Gauge, GaugeVec};
 use utils::id::{TenantId, TimelineId};
 
-use super::callbacks::{get_request_lsn, notify_proc};
-
-use tracing::{error, info, info_span, trace};
-
-use utils::lsn::Lsn;
-
-pub struct CommunicatorWorkerProcessStruct<'a> {
-    /// Tokio runtime that the main loop and any other related tasks runs in.
-    pub(crate) runtime: tokio::runtime::Runtime,
-
-    /// Client to communicate with the pageserver
-    client: PageserverClient,
-
-    /// Request slots that backends use to send IO requests to the communicator.
-    neon_request_slots: &'a [NeonIORequestSlot],
-
-    /// Notification pipe. Backends use this to notify the communicator that a request is waiting to
-    /// be processed in one of the request slots.
-    submission_pipe_read_fd: OwnedFd,
-
-    /// Locking table for all in-progress IO requests.
-    in_progress_table: RequestInProgressTable,
-
-    /// Local File Cache, relation size tracking, last-written LSN tracking
-    pub(crate) cache: IntegratedCacheWriteAccess<'a>,
+pub struct CommunicatorWorkerProcessStruct {
+    runtime: tokio::runtime::Runtime,
 
     /*** Metrics ***/
     pub(crate) lfc_metrics: LfcMetricsCollector,
-
-    request_counters: GaugeVec<RequestTypeLabelGroupSet>,
-
-    getpage_cache_misses_counter: Gauge,
-    getpage_cache_hits_counter: Gauge,
-
-    // For the requests that affect multiple blocks, have separate counters for the # of blocks affected
-    request_nblocks_counters: GaugeVec<RequestTypeLabelGroupSet>,
-
-    allocator_metrics: MyAllocatorCollector,
-}
-
-// Define a label group, consisting of 1 or more label values
-#[derive(measured::LabelGroup)]
-#[label(set = RequestTypeLabelGroupSet)]
-struct RequestTypeLabelGroup {
-    request_type: crate::neon_request::NeonIORequestDiscriminants,
-}
-
-impl RequestTypeLabelGroup {
-    fn from_req(req: &NeonIORequest) -> Self {
-        RequestTypeLabelGroup {
-            request_type: req.into(),
-        }
-    }
 }
 
 /// Launch the communicator process's Rust subsystems
-#[allow(clippy::too_many_arguments)]
-pub(super) fn init_legacy() -> Result<(), String> {
-    let runtime = tokio::runtime::Builder::new_multi_thread()
-        .enable_all()
-        .thread_name("communicator thread")
-        .build()
-        .unwrap();
-
-    // Start the listener on the control socket
-    runtime
-        .block_on(control_socket::launch_listener(None))
-        .map_err(|e| e.to_string())?;
-
-    Box::leak(Box::new(runtime));
-
-    Ok(())
-}
-
-/// Launch the communicator process's Rust subsystems
-#[allow(clippy::too_many_arguments)]
 pub(super) fn init(
-    cis: CommunicatorInitStruct,
-    tenant_id: &str,
-    timeline_id: &str,
-    auth_token: Option<&str>,
-    shard_map: HashMap<utils::shard::ShardIndex, String>,
-    stripe_size: Option<ShardStripeSize>,
-    initial_file_cache_size: u64,
-    file_cache_path: Option<PathBuf>,
-) -> Result<&'static CommunicatorWorkerProcessStruct<'static>, String> {
+    tenant_id: Option<&str>,
+    timeline_id: Option<&str>,
+) -> Result<&'static CommunicatorWorkerProcessStruct, String> {
     // The caller validated these already
-    let tenant_id = TenantId::from_str(tenant_id).map_err(|e| format!("invalid tenant ID: {e}"))?;
-    let timeline_id =
-        TimelineId::from_str(timeline_id).map_err(|e| format!("invalid timeline ID: {e}"))?;
-    let shard_spec =
-        ShardSpec::new(shard_map, stripe_size).map_err(|e| format!("invalid shard spec: {e}:"))?;
+    let _tenant_id = tenant_id
+        .map(TenantId::from_str)
+        .transpose()
+        .map_err(|e| format!("invalid tenant ID: {e}"))?;
+    let _timeline_id = timeline_id
+        .map(TimelineId::from_str)
+        .transpose()
+        .map_err(|e| format!("invalid timeline ID: {e}"))?;
 
     let runtime = tokio::runtime::Builder::new_multi_thread()
         .enable_all()
@@ -128,716 +36,31 @@ pub(super) fn init(
         .build()
         .unwrap();
 
-    let last_lsn = get_request_lsn();
-
-    let file_cache = if let Some(path) = file_cache_path {
-        Some(FileCache::new(&path, initial_file_cache_size).expect("could not create cache file"))
-    } else {
-        // FIXME: temporarily for testing, use LFC even if disabled
-        Some(
-            FileCache::new(&PathBuf::from("new_filecache"), 1000)
-                .expect("could not create cache file"),
-        )
-    };
-
-    // Initialize subsystems
-    let cache = cis
-        .integrated_cache_init_struct
-        .worker_process_init(last_lsn, file_cache);
-
-    let client = {
-        let _guard = runtime.enter();
-        PageserverClient::new(
-            tenant_id,
-            timeline_id,
-            shard_spec,
-            auth_token.map(|s| s.to_string()),
-            None,
-        )
-        .expect("could not create client")
-    };
-
     let worker_struct = CommunicatorWorkerProcessStruct {
         // Note: it's important to not drop the runtime, or all the tasks are dropped
         // too. Including it in the returned struct is one way to keep it around.
         runtime,
-        neon_request_slots: cis.neon_request_slots,
-        client,
-        cache,
-        submission_pipe_read_fd: cis.submission_pipe_read_fd,
-        in_progress_table: RequestInProgressTable::new(),
 
         // metrics
         lfc_metrics: LfcMetricsCollector,
-
-        request_counters: GaugeVec::new(),
-
-        getpage_cache_misses_counter: Gauge::new(),
-        getpage_cache_hits_counter: Gauge::new(),
-
-        request_nblocks_counters: GaugeVec::new(),
-
-        allocator_metrics: MyAllocatorCollector::new(),
     };
-
     let worker_struct = Box::leak(Box::new(worker_struct));
 
-    let main_loop_handle = worker_struct.runtime.spawn(worker_struct.run());
-    worker_struct.runtime.spawn(async {
-        let err = main_loop_handle.await.unwrap_err();
-        error!("error: {err:?}");
-    });
-
     // Start the listener on the control socket
     worker_struct
         .runtime
-        .block_on(control_socket::launch_listener(Some(worker_struct)))
+        .block_on(worker_struct.launch_control_socket_listener())
         .map_err(|e| e.to_string())?;
 
     Ok(worker_struct)
 }
 
-impl<'t> CommunicatorWorkerProcessStruct<'t> {
-    /// Update the configuration
-    pub(super) fn update_shard_map(
-        &self,
-        new_shard_map: HashMap<utils::shard::ShardIndex, String>,
-        stripe_size: Option<ShardStripeSize>,
-    ) {
-        let shard_spec = ShardSpec::new(new_shard_map, stripe_size).expect("invalid shard spec");
-
-        {
-            let _in_runtime = self.runtime.enter();
-            if let Err(err) = self.client.update_shards(shard_spec) {
-                tracing::error!("could not update shard map: {err:?}");
-            }
-        }
-    }
-
-    /// Main loop of the worker process. Receive requests from the backends and process them.
-    pub(super) async fn run(&'static self) {
-        let mut idxbuf: [u8; 4] = [0; 4];
-
-        let mut submission_pipe_read =
-            PipeRead::try_from(self.submission_pipe_read_fd.as_raw_fd()).expect("invalid pipe fd");
-
-        loop {
-            // Wait for a backend to ring the doorbell
-            match submission_pipe_read.read(&mut idxbuf).await {
-                Ok(4) => {}
-                Ok(nbytes) => panic!("short read ({nbytes} bytes) on communicator pipe"),
-                Err(e) => panic!("error reading from communicator pipe: {e}"),
-            }
-            let slot_idx = u32::from_ne_bytes(idxbuf) as usize;
-
-            // Read the IO request from the slot indicated in the wakeup
-            let Some(slot) = self.neon_request_slots[slot_idx].start_processing_request() else {
-                // This currently should not happen. But if we had multiple threads picking up
-                // requests, and without waiting for the notifications, it could.
-                panic!("no request in slot");
-            };
-
-            // Ok, we have ownership of this request now. We must process it now, there's no going
-            // back.
-            //
-            // Spawn a separate task for every request. That's a little excessive for requests that
-            // can be quickly satisfied from the cache, but we expect that to be rare, because the
-            // requesting backend would have already checked the cache.
-            tokio::spawn(async move {
-                use tracing::Instrument;
-
-                let request_id = slot.get_request().request_id();
-                let owner_procno = slot.get_owner_procno();
-
-                let span = info_span!(
-                    "processing",
-                    request_id = request_id,
-                    slot_idx = slot_idx,
-                    procno = owner_procno,
-                );
-                async {
-                    // FIXME: as a temporary hack, abort the request if we don't get a response
-                    // promptly.
-                    //
-                    // Lots of regression tests are getting stuck and failing at the moment,
-                    // this makes them fail a little faster, which it faster to iterate.
-                    // This needs to be removed once more regression tests are passing.
-                    // See also similar hack in the backend code, in wait_request_completion()
-                    let result = tokio::time::timeout(
-                        tokio::time::Duration::from_secs(60),
-                        self.handle_request(slot.get_request()),
-                    )
-                    .await
-                    .unwrap_or_else(|_elapsed| {
-                        info!("request {request_id} timed out");
-                        NeonIOResult::Error(libc::ETIMEDOUT)
-                    });
-                    trace!("request {request_id} at slot {slot_idx} completed");
-
-                    // Ok, we have completed the IO. Mark the request as completed. After that,
-                    // we no longer have ownership of the slot, and must not modify it.
-                    slot.completed(result);
-
-                    // Notify the backend about the completion. (Note that the backend might see
-                    // the completed status even before this; this is just a wakeup)
-                    notify_proc(owner_procno);
-                }
-                .instrument(span)
-                .await
-            });
-        }
-    }
-
-    /// Compute the 'request_lsn' to use for a pageserver request
-    fn request_lsns(&self, not_modified_since_lsn: Lsn) -> page_api::ReadLsn {
-        let mut request_lsn = get_request_lsn();
-
-        // Is it possible that the last-written LSN is ahead of last flush LSN? Generally not, we
-        // shouldn't evict a page from the buffer cache before all its modifications have been
-        // safely flushed. That's the "WAL before data" rule. However, there are a few exceptions:
-        //
-        // - when creation an index: _bt_blwritepage logs the full page without flushing WAL before
-        // smgrextend (files are fsynced before build ends).
-        //
-        // XXX: If we make a request LSN greater than the current WAL flush LSN, the pageserver would
-        // block waiting for the WAL arrive, until we flush it and it propagates through the
-        // safekeepers to the pageserver. If there's nothing that forces the WAL to be flushed,
-        // the pageserver would get stuck waiting forever. To avoid that, all the write-
-        // functions in communicator_new.c call XLogSetAsyncXactLSN(). That nudges the WAL writer to
-        // perform the flush relatively soon.
-        //
-        // It would perhaps be nicer to do the WAL flush here, but it's tricky to call back into
-        // Postgres code to do that from here. That's why we rely on communicator_new.c to do the
-        // calls "pre-emptively".
-        //
-        // FIXME: Because of the above, it can still happen that the flush LSN is ahead of
-        // not_modified_since, if the WAL writer hasn't done the flush yet. It would be nice to know
-        // if there are other cases like that that we have mised, but unfortunately we cannot turn
-        // this into an assertion because of that legit case.
-        //
-        // See also the old logic in neon_get_request_lsns() C function
-        if not_modified_since_lsn > request_lsn {
-            tracing::info!(
-                "not_modified_since_lsn {} is ahead of last flushed LSN {}",
-                not_modified_since_lsn,
-                request_lsn
-            );
-            request_lsn = not_modified_since_lsn;
-        }
-
-        page_api::ReadLsn {
-            request_lsn,
-            not_modified_since_lsn: Some(not_modified_since_lsn),
-        }
-    }
-
-    /// Handle one IO request
-    async fn handle_request(&'static self, request: &'_ NeonIORequest) -> NeonIOResult {
-        self.request_counters
-            .inc(RequestTypeLabelGroup::from_req(request));
-        match request {
-            NeonIORequest::Empty => {
-                error!("unexpected Empty IO request");
-                NeonIOResult::Error(0)
-            }
-            NeonIORequest::RelSize(req) => {
-                let rel = req.reltag();
-
-                let _in_progress_guard = self
-                    .in_progress_table
-                    .lock(RequestInProgressKey::Rel(rel), req.request_id)
-                    .await;
-
-                // Check the cache first
-                let not_modified_since = match self.cache.get_rel_size(&rel) {
-                    CacheResult::Found(nblocks) => {
-                        tracing::trace!("found relsize for {:?} in cache: {}", rel, nblocks);
-                        return NeonIOResult::RelSize(nblocks);
-                    }
-                    // XXX: we don't cache negative entries, so if there's no entry in the cache, it could mean
-                    // that the relation doesn't exist or that we don't have it cached.
-                    CacheResult::NotFound(lsn) => lsn,
-                };
-
-                let read_lsn = self.request_lsns(not_modified_since);
-                match self
-                    .client
-                    .get_rel_size(page_api::GetRelSizeRequest {
-                        read_lsn,
-                        rel,
-                        allow_missing: req.allow_missing,
-                    })
-                    .await
-                {
-                    Ok(Some(nblocks)) => {
-                        // update the cache
-                        tracing::trace!(
-                            "updated relsize for {:?} in cache: {}, lsn {}",
-                            rel,
-                            nblocks,
-                            read_lsn
-                        );
-                        self.cache
-                            .remember_rel_size(&rel, nblocks, not_modified_since);
-
-                        NeonIOResult::RelSize(nblocks)
-                    }
-                    Ok(None) => {
-                        // TODO: cache negative entry?
-                        NeonIOResult::RelSize(INVALID_BLOCK_NUMBER)
-                    }
-                    Err(err) => {
-                        // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                        info!("tonic error: {err:?}");
-                        NeonIOResult::Error(libc::EIO)
-                    }
-                }
-            }
-            NeonIORequest::GetPageV(req) => match self.handle_get_pagev_request(req).await {
-                Ok(()) => NeonIOResult::GetPageV,
-                Err(errno) => NeonIOResult::Error(errno),
-            },
-            NeonIORequest::GetPageVUncached(req) => {
-                match self.handle_get_pagev_uncached_request(req).await {
-                    Ok(()) => NeonIOResult::GetPageV,
-                    Err(errno) => NeonIOResult::Error(errno),
-                }
-            }
-            NeonIORequest::ReadSlruSegment(req) => {
-                let lsn = Lsn(req.request_lsn);
-                let file_path = req.destination_file_path();
-
-                match self
-                    .client
-                    .get_slru_segment(page_api::GetSlruSegmentRequest {
-                        read_lsn: self.request_lsns(lsn),
-                        kind: req.slru_kind,
-                        segno: req.segment_number,
-                    })
-                    .await
-                {
-                    Ok(slru_bytes) => {
-                        if let Err(e) = tokio::fs::write(&file_path, &slru_bytes).await {
-                            error!("could not write slru segment to file {file_path}: {e}");
-                            return NeonIOResult::Error(e.raw_os_error().unwrap_or(libc::EIO));
-                        }
-
-                        let blocks_count = slru_bytes.len() / crate::BLCKSZ;
-
-                        NeonIOResult::ReadSlruSegment(blocks_count as _)
-                    }
-                    Err(err) => {
-                        // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                        info!("tonic error: {err:?}");
-                        NeonIOResult::Error(libc::EIO)
-                    }
-                }
-            }
-            NeonIORequest::PrefetchV(req) => {
-                self.request_nblocks_counters
-                    .inc_by(RequestTypeLabelGroup::from_req(request), req.nblocks as i64);
-                let req = *req;
-                // FIXME: handle_request() runs in a separate task already, do we really need to spawn a new one here?
-                tokio::spawn(async move { self.handle_prefetchv_request(&req).await });
-                NeonIOResult::PrefetchVLaunched
-            }
-            NeonIORequest::DbSize(req) => {
-                let _in_progress_guard = self
-                    .in_progress_table
-                    .lock(RequestInProgressKey::Db(req.db_oid), req.request_id)
-                    .await;
-
-                // Check the cache first
-                let not_modified_since = match self.cache.get_db_size(req.db_oid) {
-                    CacheResult::Found(db_size) => {
-                        // get_page already copied the block content to the destination
-                        return NeonIOResult::DbSize(db_size);
-                    }
-                    CacheResult::NotFound(lsn) => lsn,
-                };
-
-                match self
-                    .client
-                    .get_db_size(page_api::GetDbSizeRequest {
-                        read_lsn: self.request_lsns(not_modified_since),
-                        db_oid: req.db_oid,
-                    })
-                    .await
-                {
-                    Ok(db_size) => NeonIOResult::DbSize(db_size),
-                    Err(err) => {
-                        // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                        info!("tonic error: {err:?}");
-                        NeonIOResult::Error(libc::EIO)
-                    }
-                }
-            }
-
-            // Write requests
-            NeonIORequest::WritePage(req) => {
-                let rel = req.reltag();
-                let _in_progress_guard = self
-                    .in_progress_table
-                    .lock(
-                        RequestInProgressKey::Block(rel, req.block_number),
-                        req.request_id,
-                    )
-                    .await;
-
-                // We must at least update the last-written LSN on the page, but also store the page
-                // image in the LFC while we still have it
-                self.cache
-                    .remember_page(&rel, req.block_number, req.src, Lsn(req.lsn), true)
-                    .await;
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::RelExtend(req) => {
-                let rel = req.reltag();
-                let _in_progress_guard = self
-                    .in_progress_table
-                    .lock(
-                        RequestInProgressKey::Block(rel, req.block_number),
-                        req.request_id,
-                    )
-                    .await;
-
-                // We must at least update the last-written LSN on the page and the relation size,
-                // but also store the page image in the LFC while we still have it
-                self.cache
-                    .remember_page(&rel, req.block_number, req.src, Lsn(req.lsn), true)
-                    .await;
-                self.cache
-                    .remember_rel_size(&req.reltag(), req.block_number + 1, Lsn(req.lsn));
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::RelZeroExtend(req) => {
-                self.request_nblocks_counters
-                    .inc_by(RequestTypeLabelGroup::from_req(request), req.nblocks as i64);
-
-                // TODO: need to grab an io-in-progress lock for this? I guess not
-                // TODO: We could put the empty pages to the cache. Maybe have
-                // a marker on the block entries for all-zero pages, instead of
-                // actually storing the empty pages.
-                self.cache.remember_rel_size(
-                    &req.reltag(),
-                    req.block_number + req.nblocks,
-                    Lsn(req.lsn),
-                );
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::RelCreate(req) => {
-                // TODO: need to grab an io-in-progress lock for this? I guess not
-                self.cache.remember_rel_size(&req.reltag(), 0, Lsn(req.lsn));
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::RelTruncate(req) => {
-                // TODO: need to grab an io-in-progress lock for this? I guess not
-                self.cache
-                    .remember_rel_size(&req.reltag(), req.nblocks, Lsn(req.lsn));
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::RelUnlink(req) => {
-                // TODO: need to grab an io-in-progress lock for this? I guess not
-                self.cache.forget_rel(&req.reltag(), None, Lsn(req.lsn));
-                NeonIOResult::WriteOK
-            }
-            NeonIORequest::UpdateCachedRelSize(req) => {
-                // TODO: need to grab an io-in-progress lock for this? I guess not
-                self.cache
-                    .remember_rel_size(&req.reltag(), req.nblocks, Lsn(req.lsn));
-                NeonIOResult::WriteOK
-            }
-        }
-    }
-
-    /// Subroutine to handle a GetPageV request, since it's a little more complicated than
-    /// others.
-    async fn handle_get_pagev_request(&'t self, req: &CGetPageVRequest) -> Result<(), i32> {
-        let rel = req.reltag();
-
-        // Check the cache first
-        //
-        // Note: Because the backends perform a direct lookup in the cache before sending
-        // the request to the communicator process, we expect the pages to almost never
-        // be already in cache. It could happen if:
-        // 1. two backends try to read the same page at the same time, but that should never
-        //    happen because there's higher level locking in the Postgres buffer manager, or
-        // 2. a prefetch request finished at the same time as a backend requested the
-        //    page. That's much more likely.
-        let mut cache_misses = Vec::with_capacity(req.nblocks as usize);
-        for i in 0..req.nblocks {
-            let blkno = req.block_number + i as u32;
-
-            // note: this is deadlock-safe even though we hold multiple locks at the same time,
-            // because they're always acquired in the same order.
-            let in_progress_guard = self
-                .in_progress_table
-                .lock(RequestInProgressKey::Block(rel, blkno), req.request_id)
-                .await;
-
-            let dest = req.dest[i as usize];
-            let not_modified_since = match self.cache.get_page(&rel, blkno, dest).await {
-                Ok(CacheResult::Found(_)) => {
-                    // get_page already copied the block content to the destination
-                    trace!("found blk {} in rel {:?} in LFC", blkno, rel);
-                    continue;
-                }
-                Ok(CacheResult::NotFound(lsn)) => lsn,
-                Err(_io_error) => return Err(libc::EIO), // FIXME print the error?
-            };
-            cache_misses.push((blkno, not_modified_since, dest, in_progress_guard));
-        }
-        self.getpage_cache_misses_counter
-            .inc_by(cache_misses.len() as i64);
-        self.getpage_cache_hits_counter
-            .inc_by(req.nblocks as i64 - cache_misses.len() as i64);
-
-        if cache_misses.is_empty() {
-            return Ok(());
-        }
-        let not_modified_since = cache_misses
-            .iter()
-            .map(|(_blkno, lsn, _dest, _guard)| *lsn)
-            .max()
-            .unwrap();
-
-        // Construct a pageserver request for the cache misses
-        let block_numbers: Vec<u32> = cache_misses
-            .iter()
-            .map(|(blkno, _lsn, _dest, _guard)| *blkno)
-            .collect();
-        let read_lsn = self.request_lsns(not_modified_since);
-        trace!(
-            "sending getpage request for blocks {:?} in rel {:?} lsns {}",
-            block_numbers, rel, read_lsn
-        );
-        match self
-            .client
-            .get_page(page_api::GetPageRequest {
-                request_id: req.request_id.into(),
-                request_class: page_api::GetPageClass::Normal,
-                read_lsn,
-                rel,
-                block_numbers: block_numbers.clone(),
-            })
-            .await
-        {
-            Ok(resp) => {
-                // Write the received page images directly to the shared memory location
-                // that the backend requested.
-                if resp.pages.len() != block_numbers.len() {
-                    error!(
-                        "received unexpected response with {} page images from pageserver for a request for {} pages",
-                        resp.pages.len(),
-                        block_numbers.len(),
-                    );
-                    return Err(libc::EIO);
-                }
-
-                trace!(
-                    "received getpage response for blocks {:?} in rel {:?} lsns {}",
-                    block_numbers, rel, read_lsn
-                );
-
-                for (page, (blkno, _lsn, dest, _guard)) in resp.pages.into_iter().zip(cache_misses)
-                {
-                    let src: &[u8] = page.image.as_ref();
-                    let len = std::cmp::min(src.len(), dest.bytes_total());
-                    unsafe {
-                        std::ptr::copy_nonoverlapping(src.as_ptr(), dest.as_mut_ptr(), len);
-                    };
-
-                    // Also store it in the LFC while we have it
-                    self.cache
-                        .remember_page(
-                            &rel,
-                            blkno,
-                            page.image,
-                            read_lsn.not_modified_since_lsn.unwrap(),
-                            false,
-                        )
-                        .await;
-                }
-            }
-            Err(err) => {
-                // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                info!("tonic error: {err:?}");
-                return Err(libc::EIO);
-            }
-        }
-        Ok(())
-    }
-
-    /// Subroutine to handle an GetPageVUncached request.
-    ///
-    /// Note: this bypasses the cache, in-progress IO locking, and all other side-effects.
-    /// This request type is only used in tests.
-    async fn handle_get_pagev_uncached_request(
-        &'t self,
-        req: &CGetPageVUncachedRequest,
-    ) -> Result<(), i32> {
-        let rel = req.reltag();
-
-        // Construct a pageserver request
-        let block_numbers: Vec<u32> =
-            (req.block_number..(req.block_number + (req.nblocks as u32))).collect();
-        let read_lsn = page_api::ReadLsn {
-            request_lsn: Lsn(req.request_lsn),
-            not_modified_since_lsn: Some(Lsn(req.not_modified_since)),
-        };
-        trace!(
-            "sending (uncached) getpage request for blocks {:?} in rel {:?} lsns {}",
-            block_numbers, rel, read_lsn
-        );
-        match self
-            .client
-            .get_page(page_api::GetPageRequest {
-                request_id: req.request_id.into(),
-                request_class: page_api::GetPageClass::Normal,
-                read_lsn,
-                rel,
-                block_numbers: block_numbers.clone(),
-            })
-            .await
-        {
-            Ok(resp) => {
-                // Write the received page images directly to the shared memory location
-                // that the backend requested.
-                if resp.pages.len() != block_numbers.len() {
-                    error!(
-                        "received unexpected response with {} page images from pageserver for a request for {} pages",
-                        resp.pages.len(),
-                        block_numbers.len(),
-                    );
-                    return Err(libc::EIO);
-                }
-
-                trace!(
-                    "received getpage response for blocks {:?} in rel {:?} lsns {}",
-                    block_numbers, rel, read_lsn
-                );
-
-                for (page, dest) in resp.pages.into_iter().zip(req.dest) {
-                    let src: &[u8] = page.image.as_ref();
-                    let len = std::cmp::min(src.len(), dest.bytes_total());
-                    unsafe {
-                        std::ptr::copy_nonoverlapping(src.as_ptr(), dest.as_mut_ptr(), len);
-                    };
-                }
-            }
-            Err(err) => {
-                // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                info!("tonic error: {err:?}");
-                return Err(libc::EIO);
-            }
-        }
-        Ok(())
-    }
-
-    /// Subroutine to handle a PrefetchV request, since it's a little more complicated than
-    /// others.
-    ///
-    /// This is very similar to a GetPageV request, but the results are only stored in the cache.
-    async fn handle_prefetchv_request(&'static self, req: &CPrefetchVRequest) -> Result<(), i32> {
-        let rel = req.reltag();
-
-        // Check the cache first
-        let mut cache_misses = Vec::with_capacity(req.nblocks as usize);
-        for i in 0..req.nblocks {
-            let blkno = req.block_number + i as u32;
-
-            // note: this is deadlock-safe even though we hold multiple locks at the same time,
-            // because they're always acquired in the same order.
-            let in_progress_guard = self
-                .in_progress_table
-                .lock(RequestInProgressKey::Block(rel, blkno), req.request_id)
-                .await;
-
-            let not_modified_since = match self.cache.page_is_cached(&rel, blkno).await {
-                Ok(CacheResult::Found(_)) => {
-                    trace!("found blk {} in rel {:?} in LFC", blkno, rel);
-                    continue;
-                }
-                Ok(CacheResult::NotFound(lsn)) => lsn,
-                Err(_io_error) => return Err(libc::EIO), // FIXME print the error?
-            };
-            cache_misses.push((blkno, not_modified_since, in_progress_guard));
-        }
-        if cache_misses.is_empty() {
-            return Ok(());
-        }
-        let not_modified_since = cache_misses
-            .iter()
-            .map(|(_blkno, lsn, _guard)| *lsn)
-            .max()
-            .unwrap();
-        let block_numbers: Vec<u32> = cache_misses
-            .iter()
-            .map(|(blkno, _lsn, _guard)| *blkno)
-            .collect();
-
-        // TODO: spawn separate tasks for these. Use the integrated cache to keep track of the
-        // in-flight requests
-
-        match self
-            .client
-            .get_page(page_api::GetPageRequest {
-                request_id: req.request_id.into(),
-                request_class: page_api::GetPageClass::Prefetch,
-                read_lsn: self.request_lsns(not_modified_since),
-                rel,
-                block_numbers: block_numbers.clone(),
-            })
-            .await
-        {
-            Ok(resp) => {
-                trace!(
-                    "prefetch completed, remembering blocks {:?} in rel {:?} in LFC",
-                    block_numbers, rel
-                );
-                if resp.pages.len() != block_numbers.len() {
-                    error!(
-                        "received unexpected response with {} page images from pageserver for a request for {} pages",
-                        resp.pages.len(),
-                        block_numbers.len(),
-                    );
-                    return Err(libc::EIO);
-                }
-
-                for (page, (blkno, _lsn, _guard)) in resp.pages.into_iter().zip(cache_misses) {
-                    self.cache
-                        .remember_page(&rel, blkno, page.image, not_modified_since, false)
-                        .await;
-                }
-            }
-            Err(err) => {
-                // FIXME: Could we map the tonic StatusCode to a libc errno in a more fine-grained way? Or pass the error message to the backend
-                info!("tonic error: {err:?}");
-                return Err(libc::EIO);
-            }
-        }
-        Ok(())
-    }
-}
-
-impl<T> MetricGroup<T> for CommunicatorWorkerProcessStruct<'_>
+impl<T> MetricGroup<T> for CommunicatorWorkerProcessStruct
 where
     T: Encoding,
-    CounterState: MetricEncoding<T>,
     GaugeState: MetricEncoding<T>,
 {
     fn collect_group_into(&self, enc: &mut T) -> Result<(), T::Err> {
-        use measured::metric::MetricFamilyEncoding;
-        use measured::metric::name::MetricName;
-
-        self.lfc_metrics.collect_group_into(enc)?;
-        self.cache.collect_group_into(enc)?;
-        self.request_counters
-            .collect_family_into(MetricName::from_str("request_counters"), enc)?;
-        self.request_nblocks_counters
-            .collect_family_into(MetricName::from_str("request_nblocks_counters"), enc)?;
-        self.allocator_metrics.collect_group_into(enc)?;
-
-        Ok(())
+        self.lfc_metrics.collect_group_into(enc)
     }
 }

pgxn/neon/communicator/src/worker_process/mod.rs

@@ -4,9 +4,9 @@
 //! - launch the main loop,
 //! - receive IO requests from backends and process them,
 //! - write results back to backends.
+
 mod callbacks;
 mod control_socket;
-mod in_progress_ios;
 mod lfc_metrics;
 mod logging;
 mod main_loop;

pgxn/neon/communicator/src/worker_process/worker_interface.rs

@@ -1,21 +1,14 @@
 //! Functions called from the C code in the worker process
 
-use std::collections::HashMap;
 use std::ffi::{CStr, CString, c_char};
-use std::path::PathBuf;
 
-use crate::init::CommunicatorInitStruct;
 use crate::worker_process::main_loop;
 use crate::worker_process::main_loop::CommunicatorWorkerProcessStruct;
 
-use pageserver_client_grpc::ShardStripeSize;
-
 /// Launch the communicator's tokio tasks, which do most of the work.
 ///
 /// The caller has initialized the process as a regular PostgreSQL background worker
-/// process. The shared memory segment used to communicate with the backends has been
-/// allocated and initialized earlier, at postmaster startup, in
-/// rcommunicator_shmem_init().
+/// process.
 ///
 /// Inputs:
 ///   `tenant_id` and `timeline_id` can be NULL, if we're been launched in "non-Neon" mode,
@@ -30,63 +23,27 @@ use pageserver_client_grpc::ShardStripeSize;
 /// This is called only once in the process, so the returned struct, and error message in
 /// case of failure, are simply leaked.
 #[unsafe(no_mangle)]
-pub extern "C" fn communicator_worker_process_launch(
-    cis: Box<CommunicatorInitStruct>,
+pub extern "C" fn communicator_worker_launch(
     tenant_id: *const c_char,
     timeline_id: *const c_char,
-    auth_token: *const c_char,
-    shard_map: *mut *mut c_char,
-    nshards: u32,
-    stripe_size: u32,
-    file_cache_path: *const c_char,
-    initial_file_cache_size: u64,
     error_p: *mut *const c_char,
-) -> Option<&'static CommunicatorWorkerProcessStruct<'static>> {
-    tracing::warn!("starting threads in rust code");
+) -> Option<&'static CommunicatorWorkerProcessStruct> {
     // Convert the arguments into more convenient Rust types
-    let tenant_id = {
-        let cstr = unsafe { CStr::from_ptr(tenant_id) };
-        cstr.to_str().expect("assume UTF-8")
-    };
-    let timeline_id = {
-        let cstr = unsafe { CStr::from_ptr(timeline_id) };
-        cstr.to_str().expect("assume UTF-8")
-    };
-    let auth_token = if auth_token.is_null() {
+    let tenant_id = if tenant_id.is_null() {
         None
     } else {
-        let cstr = unsafe { CStr::from_ptr(auth_token) };
+        let cstr = unsafe { CStr::from_ptr(tenant_id) };
         Some(cstr.to_str().expect("assume UTF-8"))
     };
-    let file_cache_path = {
-        if file_cache_path.is_null() {
-            None
-        } else {
-            let c_str = unsafe { CStr::from_ptr(file_cache_path) };
-            Some(PathBuf::from(c_str.to_str().unwrap()))
-        }
-    };
-    let shard_map = shard_map_to_hash(nshards, shard_map);
-    // FIXME: distinguish between unsharded, and sharded with 1 shard
-    // Also, we might go from unsharded to sharded while the system
-    // is running.
-    let stripe_size = if stripe_size > 0 && nshards > 1 {
-        Some(ShardStripeSize(stripe_size))
-    } else {
+    let timeline_id = if timeline_id.is_null() {
         None
+    } else {
+        let cstr = unsafe { CStr::from_ptr(timeline_id) };
+        Some(cstr.to_str().expect("assume UTF-8"))
     };
 
     // The `init` function does all the work.
-    let result = main_loop::init(
-        *cis,
-        tenant_id,
-        timeline_id,
-        auth_token,
-        shard_map,
-        stripe_size,
-        initial_file_cache_size,
-        file_cache_path,
-    );
+    let result = main_loop::init(tenant_id, timeline_id);
 
     // On failure, return the error message to the C caller in *error_p.
     match result {
@@ -101,68 +58,3 @@ pub extern "C" fn communicator_worker_process_launch(
         }
     }
 }
-
-#[unsafe(no_mangle)]
-pub extern "C" fn communicator_worker_process_launch_legacy(error_p: *mut *const c_char) -> bool {
-    // The `init` function does all the work.
-    let result = main_loop::init_legacy();
-
-    // On failure, return the error message to the C caller in *error_p.
-    match result {
-        Ok(()) => true,
-        Err(errmsg) => {
-            let errmsg = CString::new(errmsg).expect("no nuls within error message");
-            let errmsg = Box::leak(errmsg.into_boxed_c_str());
-            let p: *const c_char = errmsg.as_ptr();
-
-            unsafe { *error_p = p };
-            false
-        }
-    }
-}
-
-/// Convert the "shard map" from an array of C strings, indexed by shard no to a rust HashMap
-fn shard_map_to_hash(
-    nshards: u32,
-    shard_map: *mut *mut c_char,
-) -> HashMap<utils::shard::ShardIndex, String> {
-    use utils::shard::*;
-
-    assert!(nshards <= u8::MAX as u32);
-
-    let mut result: HashMap<ShardIndex, String> = HashMap::new();
-    let mut p = shard_map;
-
-    for i in 0..nshards {
-        let c_str = unsafe { CStr::from_ptr(*p) };
-
-        p = unsafe { p.add(1) };
-
-        let s = c_str.to_str().unwrap();
-        let k = if nshards > 1 {
-            ShardIndex::new(ShardNumber(i as u8), ShardCount(nshards as u8))
-        } else {
-            ShardIndex::unsharded()
-        };
-        result.insert(k, s.into());
-    }
-    result
-}
-
-/// Inform the rust code about a configuration change
-#[unsafe(no_mangle)]
-pub extern "C" fn communicator_worker_config_reload(
-    proc_handle: &'static CommunicatorWorkerProcessStruct<'static>,
-    file_cache_size: u64,
-    shard_map: *mut *mut c_char,
-    nshards: u32,
-    stripe_size: u32,
-) {
-	proc_handle.runtime.spawn_blocking(move || {
-		proc_handle.cache.resize_file_cache(file_cache_size as u32);
-	});
-
-    let shard_map = shard_map_to_hash(nshards, shard_map);
-    let stripe_size = (nshards > 1).then_some(ShardStripeSize(stripe_size));
-    proc_handle.update_shard_map(shard_map, stripe_size);
-}

pgxn/neon/communicator_new.h

@@ -1,69 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * communicator_new.h
- *	  new implementation
- *
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *-------------------------------------------------------------------------
- */
-#ifndef COMMUNICATOR_NEW_H
-#define COMMUNICATOR_NEW_H
-
-#include "storage/buf_internals.h"
-
-#include "lfc_prewarm.h"
-#include "neon.h"
-#include "neon_pgversioncompat.h"
-#include "pagestore_client.h"
-
-/* initialization at postmaster startup */
-extern void CommunicatorNewShmemRequest(void);
-extern void CommunicatorNewShmemInit(void);
-
-/* initialization at backend startup */
-extern void communicator_new_init(void);
-
-/* Read requests */
-extern bool communicator_new_rel_exists(NRelFileInfo rinfo, ForkNumber forkNum);
-extern BlockNumber communicator_new_rel_nblocks(NRelFileInfo rinfo, ForkNumber forknum);
-extern int64 communicator_new_dbsize(Oid dbNode);
-extern void communicator_new_readv(NRelFileInfo rinfo, ForkNumber forkNum,
-								   BlockNumber base_blockno,
-								   void **buffers, BlockNumber nblocks);
-extern void communicator_new_read_at_lsn_uncached(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blockno,
-												  void *buffer, XLogRecPtr request_lsn, XLogRecPtr not_modified_since);
-extern void communicator_new_prefetch_register_bufferv(NRelFileInfo rinfo, ForkNumber forkNum,
-													   BlockNumber blockno,
-													   BlockNumber nblocks);
-extern bool communicator_new_update_lwlsn_for_block_if_not_cached(NRelFileInfo rinfo, ForkNumber forkNum,
-																  BlockNumber blockno, XLogRecPtr lsn);
-extern int	communicator_new_read_slru_segment(
-											   SlruKind kind,
-											   uint32_t segno,
-											   neon_request_lsns * request_lsns,
-											   const char *path
-);
-
-/* Write requests, to keep the caches up-to-date */
-extern void communicator_new_write_page(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blockno,
-										const void *buffer, XLogRecPtr lsn);
-extern void communicator_new_rel_extend(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blockno,
-										const void *buffer, XLogRecPtr lsn);
-extern void communicator_new_rel_zeroextend(NRelFileInfo rinfo, ForkNumber forkNum,
-											BlockNumber blockno, BlockNumber nblocks,
-											XLogRecPtr lsn);
-extern void communicator_new_rel_create(NRelFileInfo rinfo, ForkNumber forkNum, XLogRecPtr lsn);
-extern void communicator_new_rel_truncate(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks, XLogRecPtr lsn);
-extern void communicator_new_rel_unlink(NRelFileInfo rinfo, ForkNumber forkNum, XLogRecPtr lsn);
-extern void communicator_new_update_cached_rel_size(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks, XLogRecPtr lsn);
-
-/* other functions */
-extern int32 communicator_new_approximate_working_set_size_seconds(time_t duration, bool reset);
-extern struct LfcMetrics communicator_new_get_lfc_metrics_unsafe(void);
-extern FileCacheState *communicator_new_get_lfc_state(size_t max_entries);
-extern struct LfcStatsEntry *communicator_new_lfc_get_stats(size_t *num_entries);
-
-#endif							/* COMMUNICATOR_NEW_H */

pgxn/neon/communicator_process.c

@@ -18,9 +18,6 @@
 #include <unistd.h>
 
 #include "miscadmin.h"
-#if PG_VERSION_NUM >= 150000
-#include "access/xlogrecovery.h"
-#endif
 #include "postmaster/bgworker.h"
 #include "postmaster/interrupt.h"
 #include "postmaster/postmaster.h"
@@ -32,18 +29,14 @@
 #include "tcop/tcopprot.h"
 #include "utils/timestamp.h"
 
-#include "communicator_new.h"
 #include "communicator_process.h"
 #include "file_cache.h"
 #include "neon.h"
 #include "neon_perf_counters.h"
-#include "pagestore_client.h"
 
 /* the rust bindings, generated by cbindgen */
 #include "communicator/communicator_bindings.h"
 
-struct CommunicatorInitStruct *cis;
-
 static void pump_logging(struct LoggingReceiver *logging);
 PGDLLEXPORT void communicator_new_bgworker_main(Datum main_arg);
 
@@ -77,13 +70,9 @@ pg_init_communicator_process(void)
 void
 communicator_new_bgworker_main(Datum main_arg)
 {
-	char	  **connstrings;
-	ShardMap	shard_map;
-	uint64		file_cache_size;
 	struct LoggingReceiver *logging;
 	const char *errmsg = NULL;
 	const struct CommunicatorWorkerProcessStruct *proc_handle;
-	bool		success;
 
 	/*
 	 * Pretend that this process is a WAL sender. That affects the shutdown
@@ -119,43 +108,12 @@ communicator_new_bgworker_main(Datum main_arg)
 
 	logging = communicator_worker_configure_logging();
 
-	if (cis != NULL)
-	{
-		/* lfc_size_limit is in MBs */
-		file_cache_size = lfc_size_limit * (1024 * 1024 / BLCKSZ);
-		if (file_cache_size < 100)
-			file_cache_size = 100;
-
-		if (!parse_shard_map(pageserver_grpc_urls, &shard_map))
-		{
-			/* shouldn't happen, as the GUC was verified already */
-			elog(FATAL, "could not parse neon.pageserver_grpcs_urls");
-		}
-		connstrings = palloc(shard_map.num_shards * sizeof(char *));
-		for (int i = 0; i < shard_map.num_shards; i++)
-			connstrings[i] = shard_map.connstring[i];
-		AssignNumShards(shard_map.num_shards);
-		proc_handle = communicator_worker_process_launch(
-			cis,
-			neon_tenant,
-			neon_timeline,
-			neon_auth_token,
-			connstrings,
-			shard_map.num_shards,
-			neon_stripe_size,
-			lfc_path,
-			file_cache_size,
-			&errmsg);
-		pfree(connstrings);
-		cis = NULL;
-		success = proc_handle != NULL;
-	}
-	else
-	{
-		proc_handle = NULL;
-		success = communicator_worker_process_launch_legacy(&errmsg);
-	}
-	if (!success)
+	proc_handle = communicator_worker_launch(
+		neon_tenant[0] == '\0' ? NULL : neon_tenant,
+		neon_timeline[0] == '\0' ? NULL : neon_timeline,
+		&errmsg
+		);
+	if (proc_handle == NULL)
 	{
 		/*
 		 * Something went wrong. Before exiting, forward any log messages that
@@ -215,32 +173,6 @@ communicator_new_bgworker_main(Datum main_arg)
 		{
 			ConfigReloadPending = false;
 			ProcessConfigFile(PGC_SIGHUP);
-
-			if (proc_handle)
-			{
-				/* lfc_size_limit is in MBs */
-				file_cache_size = lfc_size_limit * (1024 * 1024 / BLCKSZ);
-				if (file_cache_size < 100)
-					file_cache_size = 100;
-
-				/* Reload pageserver URLs */
-				if (!parse_shard_map(pageserver_grpc_urls, &shard_map))
-				{
-					/* shouldn't happen, as the GUC was verified already */
-					elog(FATAL, "could not parse neon.pageserver_grpcs_urls");
-				}
-				connstrings = palloc(shard_map.num_shards * sizeof(char *));
-				for (int i = 0; i < shard_map.num_shards; i++)
-					connstrings[i] = shard_map.connstring[i];
-
-				AssignNumShards(shard_map.num_shards);
-				communicator_worker_config_reload(proc_handle,
-												  file_cache_size,
-												  connstrings,
-												  shard_map.num_shards,
-												  neon_stripe_size);
-				pfree(connstrings);
-			}
 		}
 
 		duration = TimestampDifferenceMilliseconds(before, GetCurrentTimestamp());
@@ -339,49 +271,3 @@ callback_set_my_latch_unsafe(void)
 {
 	SetLatch(MyLatch);
 }
-
-/*
- * FIXME: The logic from neon_get_request_lsns() needs to go here, except for
- * the last-written LSN cache stuff, which is managed by the rust code now.
- */
-XLogRecPtr
-callback_get_request_lsn_unsafe(void)
-{
-	/*
-	 * NB: be very careful with what you do here! This is called from tokio
-	 * threads, so anything tha tries to take LWLocks is unsafe, for example.
-	 *
-	 * RecoveryInProgress() is OK
-	 */
-	if (RecoveryInProgress())
-	{
-		XLogRecPtr	replay_lsn = GetXLogReplayRecPtr(NULL);
-
-		return replay_lsn;
-	}
-	else
-	{
-		XLogRecPtr	flushlsn;
-
-#if PG_VERSION_NUM >= 150000
-		flushlsn = GetFlushRecPtr(NULL);
-#else
-		flushlsn = GetFlushRecPtr();
-#endif
-
-		return flushlsn;
-	}
-}
-
-/*
- * Get metrics, for the built-in metrics exporter that's part of the
- * communicator process.
- */
-struct LfcMetrics
-callback_get_lfc_metrics_unsafe(void)
-{
-	if (neon_use_communicator_worker)
-		return communicator_new_get_lfc_metrics_unsafe();
-	else
-		return lfc_get_metrics_unsafe();
-}

pgxn/neon/communicator_process.h

@@ -12,9 +12,6 @@
 #ifndef COMMUNICATOR_PROCESS_H
 #define COMMUNICATOR_PROCESS_H
 
-extern struct CommunicatorInitStruct *cis;
-
-/* initialization early at postmaster startup */
 extern void pg_init_communicator_process(void);
 
 #endif			/* COMMUNICATOR_PROCESS_H */

pgxn/neon/file_cache.c

@@ -137,6 +137,15 @@ typedef struct FileCacheEntry
 #define N_COND_VARS 	64
 #define CV_WAIT_TIMEOUT	10
 
+#define MAX_PREWARM_WORKERS 8
+
+typedef struct PrewarmWorkerState
+{
+	uint32		prewarmed_pages;
+	uint32		skipped_pages;
+	TimestampTz completed;
+} PrewarmWorkerState;
+
 typedef struct FileCacheControl
 {
 	uint64		generation;		/* generation is needed to handle correct hash
@@ -182,27 +191,47 @@ typedef struct FileCacheControl
 	 *   again.
 	 */
 	HyperLogLogState wss_estimation;
+
+	/* Prewarmer state */
+	PrewarmWorkerState prewarm_workers[MAX_PREWARM_WORKERS];
+	size_t n_prewarm_workers;
+	size_t n_prewarm_entries;
+	size_t total_prewarm_pages;
+	size_t prewarm_batch;
+	bool   prewarm_active;
+	bool   prewarm_canceled;
+	dsm_handle prewarm_lfc_state_handle;
 } FileCacheControl;
 
+#define FILE_CACHE_STATE_MAGIC 0xfcfcfcfc
+
+#define FILE_CACHE_STATE_BITMAP(fcs)	((uint8*)&(fcs)->chunks[(fcs)->n_chunks])
+#define FILE_CACHE_STATE_SIZE_FOR_CHUNKS(n_chunks)	(sizeof(FileCacheState) + (n_chunks)*sizeof(BufferTag) + (((n_chunks) * lfc_blocks_per_chunk)+7)/8)
+#define FILE_CACHE_STATE_SIZE(fcs)		(sizeof(FileCacheState) + (fcs->n_chunks)*sizeof(BufferTag) + (((fcs->n_chunks) << fcs->chunk_size_log)+7)/8)
+
 static HTAB *lfc_hash;
 static int	lfc_desc = -1;
 static LWLockId lfc_lock;
-int	lfc_max_size;
-int	lfc_size_limit;
+static int	lfc_max_size;
+static int	lfc_size_limit;
+static int	lfc_prewarm_limit;
+static int	lfc_prewarm_batch;
 static int	lfc_chunk_size_log = MAX_BLOCKS_PER_CHUNK_LOG;
 static int	lfc_blocks_per_chunk = MAX_BLOCKS_PER_CHUNK;
-char *lfc_path;
+static char *lfc_path;
 static uint64 lfc_generation;
 static FileCacheControl *lfc_ctl;
+static bool lfc_do_prewarm;
 
 bool lfc_store_prefetch_result;
 bool lfc_prewarm_update_ws_estimation;
 
-bool lfc_do_prewarm;
-bool lfc_prewarm_cancel;
+bool AmPrewarmWorker;
 
 #define LFC_ENABLED() (lfc_ctl->limit != 0)
 
+PGDLLEXPORT void lfc_prewarm_main(Datum main_arg);
+
 /*
  * Close LFC file if opened.
  * All backends should close their LFC files once LFC is disabled.
@@ -228,8 +257,6 @@ lfc_switch_off(void)
 {
 	int			fd;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (LFC_ENABLED())
 	{
 		HASH_SEQ_STATUS status;
@@ -295,8 +322,6 @@ lfc_maybe_disabled(void)
 static bool
 lfc_ensure_opened(void)
 {
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_generation != lfc_ctl->generation)
 	{
 		lfc_close_file();
@@ -322,9 +347,6 @@ LfcShmemInit(void)
 	bool		found;
 	static HASHCTL info;
 
-	if (neon_use_communicator_worker)
-		return;
-
 	if (lfc_max_size <= 0)
 		return;
 
@@ -514,6 +536,7 @@ lfc_init(void)
 	if (!process_shared_preload_libraries_in_progress)
 		neon_log(ERROR, "Neon module should be loaded via shared_preload_libraries");
 
+
 	DefineCustomBoolVariable("neon.store_prefetch_result_in_lfc",
 							"Immediately store received prefetch result in LFC",
 							NULL,
@@ -585,6 +608,32 @@ lfc_init(void)
 							lfc_check_chunk_size,
 							lfc_change_chunk_size,
 							NULL);
+
+	DefineCustomIntVariable("neon.file_cache_prewarm_limit",
+							"Maximal number of prewarmed chunks",
+							NULL,
+							&lfc_prewarm_limit,
+							INT_MAX,	/* no limit by default */
+							0,
+							INT_MAX,
+							PGC_SIGHUP,
+							0,
+							NULL,
+							NULL,
+							NULL);
+
+	DefineCustomIntVariable("neon.file_cache_prewarm_batch",
+							"Number of pages retrivied by prewarm from page server",
+							NULL,
+							&lfc_prewarm_batch,
+							64,
+							1,
+							INT_MAX,
+							PGC_SIGHUP,
+							0,
+							NULL,
+							NULL,
+							NULL);
 }
 
 /*
@@ -609,7 +658,7 @@ lfc_get_state(size_t max_entries)
 		uint8* bitmap;
 		size_t n_pages = 0;
 		size_t n_entries = Min(max_entries, lfc_ctl->used - lfc_ctl->pinned);
-		size_t state_size = FILE_CACHE_STATE_SIZE_FOR_CHUNKS(n_entries, lfc_blocks_per_chunk);
+		size_t state_size = FILE_CACHE_STATE_SIZE_FOR_CHUNKS(n_entries);
 		fcs = (FileCacheState*)palloc0(state_size);
 		SET_VARSIZE(fcs, state_size);
 		fcs->magic = FILE_CACHE_STATE_MAGIC;
@@ -654,6 +703,278 @@ lfc_get_state(size_t max_entries)
 	return fcs;
 }
 
+/*
+ * Prewarm LFC cache to the specified state. It uses lfc_prefetch function to load prewarmed page without hoilding shared buffer lock
+ * and avoid race conditions with other backends.
+ */
+void
+lfc_prewarm(FileCacheState* fcs, uint32 n_workers)
+{
+	size_t fcs_chunk_size_log;
+	size_t n_entries;
+	size_t prewarm_batch = Min(lfc_prewarm_batch, readahead_buffer_size);
+	size_t fcs_size;
+	uint32_t max_prefetch_pages;
+	dsm_segment *seg;
+	BackgroundWorkerHandle* bgw_handle[MAX_PREWARM_WORKERS];
+
+
+	if (!lfc_ensure_opened())
+		return;
+
+	if (prewarm_batch == 0 || lfc_prewarm_limit == 0 || n_workers == 0)
+	{
+		elog(LOG, "LFC: prewarm is disabled");
+		return;
+	}
+
+	if (n_workers > MAX_PREWARM_WORKERS)
+	{
+		elog(ERROR, "LFC: Too much prewarm workers, maximum is %d", MAX_PREWARM_WORKERS);
+	}
+
+	if (fcs == NULL || fcs->n_chunks == 0)
+	{
+		elog(LOG, "LFC: nothing to prewarm");
+		return;
+	}
+
+	if (fcs->magic != FILE_CACHE_STATE_MAGIC)
+	{
+		elog(ERROR, "LFC: Invalid file cache state magic: %X", fcs->magic);
+	}
+
+	fcs_size = VARSIZE(fcs);
+	if (FILE_CACHE_STATE_SIZE(fcs) != fcs_size)
+	{
+		elog(ERROR, "LFC: Invalid file cache state size: %u vs. %u", (unsigned)FILE_CACHE_STATE_SIZE(fcs), VARSIZE(fcs));
+	}
+
+	fcs_chunk_size_log = fcs->chunk_size_log;
+	if (fcs_chunk_size_log > MAX_BLOCKS_PER_CHUNK_LOG)
+	{
+		elog(ERROR, "LFC: Invalid chunk size log: %u", fcs->chunk_size_log);
+	}
+
+	n_entries = Min(fcs->n_chunks, lfc_prewarm_limit);
+	Assert(n_entries != 0);
+
+	max_prefetch_pages = n_entries << fcs_chunk_size_log;
+	if (fcs->n_pages > max_prefetch_pages) {
+		elog(ERROR, "LFC: Number of pages in file cache state (%d) is more than the limit (%d)", fcs->n_pages, max_prefetch_pages);
+	}
+
+	LWLockAcquire(lfc_lock, LW_EXCLUSIVE);
+
+	/* Do not prewarm more entries than LFC limit */
+	if (lfc_ctl->limit <= lfc_ctl->size)
+	{
+		elog(LOG, "LFC: skip prewarm because LFC is already filled");
+		LWLockRelease(lfc_lock);
+		return;
+	}
+
+	if (lfc_ctl->prewarm_active)
+	{
+		LWLockRelease(lfc_lock);
+		elog(ERROR, "LFC: skip prewarm because another prewarm is still active");
+	}
+	lfc_ctl->n_prewarm_entries = n_entries;
+	lfc_ctl->n_prewarm_workers = n_workers;
+	lfc_ctl->prewarm_active = true;
+	lfc_ctl->prewarm_canceled = false;
+	lfc_ctl->prewarm_batch = prewarm_batch;
+	memset(lfc_ctl->prewarm_workers, 0, n_workers*sizeof(PrewarmWorkerState));
+
+	LWLockRelease(lfc_lock);
+
+	/* Calculate total number of pages to be prewarmed */
+	lfc_ctl->total_prewarm_pages = fcs->n_pages;
+
+	seg = dsm_create(fcs_size, 0);
+	memcpy(dsm_segment_address(seg), fcs, fcs_size);
+	lfc_ctl->prewarm_lfc_state_handle = dsm_segment_handle(seg);
+
+	/* Spawn background workers */
+	for (uint32 i = 0; i < n_workers; i++)
+	{
+		BackgroundWorker worker = {0};
+
+		worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
+		worker.bgw_start_time = BgWorkerStart_ConsistentState;
+		worker.bgw_restart_time = BGW_NEVER_RESTART;
+		strcpy(worker.bgw_library_name, "neon");
+		strcpy(worker.bgw_function_name, "lfc_prewarm_main");
+		snprintf(worker.bgw_name, BGW_MAXLEN, "LFC prewarm worker %d", i+1);
+		strcpy(worker.bgw_type, "LFC prewarm worker");
+		worker.bgw_main_arg = Int32GetDatum(i);
+		/* must set notify PID to wait for shutdown */
+		worker.bgw_notify_pid = MyProcPid;
+
+		if (!RegisterDynamicBackgroundWorker(&worker, &bgw_handle[i]))
+		{
+			ereport(LOG,
+					(errcode(ERRCODE_INSUFFICIENT_RESOURCES),
+					 errmsg("LFC: registering dynamic bgworker prewarm failed"),
+					 errhint("Consider increasing the configuration parameter \"%s\".", "max_worker_processes")));
+			n_workers = i;
+			lfc_ctl->prewarm_canceled = true;
+			break;
+		}
+	}
+
+	for (uint32 i = 0; i < n_workers; i++)
+	{
+		bool interrupted;
+		do
+		{
+			interrupted = false;
+			PG_TRY();
+			{
+				BgwHandleStatus status = WaitForBackgroundWorkerShutdown(bgw_handle[i]);
+				if (status != BGWH_STOPPED && status != BGWH_POSTMASTER_DIED)
+				{
+					elog(LOG, "LFC: Unexpected status of prewarm worker termination: %d", status);
+				}
+			}
+			PG_CATCH();
+			{
+				elog(LOG, "LFC: cancel prewarm");
+				lfc_ctl->prewarm_canceled = true;
+				interrupted = true;
+			}
+			PG_END_TRY();
+		} while (interrupted);
+
+		if (!lfc_ctl->prewarm_workers[i].completed)
+		{
+			/* Background worker doesn't set completion time: it means that it was abnormally terminated */
+			elog(LOG, "LFC: prewarm worker %d failed", i+1);
+			/* Set completion time to prevent get_prewarm_info from considering this worker as active */
+			lfc_ctl->prewarm_workers[i].completed = GetCurrentTimestamp();
+		}
+	}
+	dsm_detach(seg);
+
+	LWLockAcquire(lfc_lock, LW_EXCLUSIVE);
+	lfc_ctl->prewarm_active = false;
+	LWLockRelease(lfc_lock);
+}
+
+void
+lfc_prewarm_main(Datum main_arg)
+{
+	size_t snd_idx = 0, rcv_idx = 0;
+	size_t n_sent = 0, n_received = 0;
+	size_t fcs_chunk_size_log;
+	size_t max_prefetch_pages;
+	size_t prewarm_batch;
+	size_t n_workers;
+	dsm_segment *seg;
+	FileCacheState* fcs;
+	uint8* bitmap;
+	BufferTag tag;
+	PrewarmWorkerState* ws;
+	uint32 worker_id = DatumGetInt32(main_arg);
+
+	AmPrewarmWorker = true;
+
+	pqsignal(SIGTERM, die);
+	BackgroundWorkerUnblockSignals();
+
+	seg = dsm_attach(lfc_ctl->prewarm_lfc_state_handle);
+	if (seg == NULL)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("could not map dynamic shared memory segment")));
+
+	fcs = (FileCacheState*) dsm_segment_address(seg);
+	prewarm_batch = lfc_ctl->prewarm_batch;
+	fcs_chunk_size_log = fcs->chunk_size_log;
+	n_workers = lfc_ctl->n_prewarm_workers;
+	max_prefetch_pages = lfc_ctl->n_prewarm_entries << fcs_chunk_size_log;
+	ws = &lfc_ctl->prewarm_workers[worker_id];
+	bitmap = FILE_CACHE_STATE_BITMAP(fcs);
+
+	/* enable prefetch in LFC */
+	lfc_store_prefetch_result = true;
+	lfc_do_prewarm = true; /* Flag for lfc_prefetch preventing replacement of existed entries if LFC cache is full */
+
+	elog(LOG, "LFC: worker %d start prewarming", worker_id);
+	while (!lfc_ctl->prewarm_canceled)
+	{
+		if (snd_idx < max_prefetch_pages)
+		{
+			if ((snd_idx >> fcs_chunk_size_log) % n_workers != worker_id)
+			{
+				/* If there are multiple workers, split chunks between them */
+				snd_idx += 1 << fcs_chunk_size_log;
+			}
+			else
+			{
+				if (BITMAP_ISSET(bitmap, snd_idx))
+				{
+					tag = fcs->chunks[snd_idx >> fcs_chunk_size_log];
+					tag.blockNum += snd_idx & ((1 << fcs_chunk_size_log) - 1);
+
+					if (!BufferTagIsValid(&tag)) {
+						elog(ERROR, "LFC: Invalid buffer tag: %u", tag.blockNum);
+					}
+
+					if (!lfc_cache_contains(BufTagGetNRelFileInfo(tag), tag.forkNum, tag.blockNum))
+					{
+						(void)communicator_prefetch_register_bufferv(tag, NULL, 1, NULL);
+						n_sent += 1;
+					}
+					else
+					{
+						ws->skipped_pages += 1;
+						BITMAP_CLR(bitmap, snd_idx);
+					}
+				}
+				snd_idx += 1;
+			}
+		}
+		if (n_sent >= n_received + prewarm_batch || snd_idx == max_prefetch_pages)
+		{
+			if (n_received == n_sent && snd_idx == max_prefetch_pages)
+			{
+				break;
+			}
+			if ((rcv_idx >> fcs_chunk_size_log) % n_workers != worker_id)
+			{
+				/* Skip chunks processed by other workers */
+				rcv_idx += 1 << fcs_chunk_size_log;
+				continue;
+			}
+
+			/* Locate next block to prefetch */
+			while (!BITMAP_ISSET(bitmap, rcv_idx))
+			{
+				rcv_idx += 1;
+			}
+			tag = fcs->chunks[rcv_idx >> fcs_chunk_size_log];
+			tag.blockNum += rcv_idx & ((1 << fcs_chunk_size_log) - 1);
+			if (communicator_prefetch_receive(tag))
+			{
+				ws->prewarmed_pages += 1;
+			}
+			else
+			{
+				ws->skipped_pages += 1;
+			}
+			rcv_idx += 1;
+			n_received += 1;
+		}
+	}
+	/* No need to perform prefetch cleanup here because prewarm worker will be terminated and
+	 * connection to PS dropped just after return from this function.
+	 */
+	Assert(n_sent == n_received || lfc_ctl->prewarm_canceled);
+	elog(LOG, "LFC: worker %d complete prewarming: loaded %ld pages", worker_id, (long)n_received);
+	lfc_ctl->prewarm_workers[worker_id].completed = GetCurrentTimestamp();
+}
+
 void
 lfc_invalidate(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks)
 {
@@ -661,8 +982,6 @@ lfc_invalidate(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks)
 	FileCacheEntry *entry;
 	uint32		hash;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return;
 
@@ -708,8 +1027,6 @@ lfc_cache_contains(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno)
 	bool		found = false;
 	uint32		hash;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return false;
 
@@ -745,8 +1062,6 @@ lfc_cache_containsv(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 	uint32		hash;
 	int			i = 0;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return 0;
 
@@ -854,8 +1169,6 @@ lfc_readv_select(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 	int			blocks_read = 0;
 	int			buf_offset = 0;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return -1;
 
@@ -1166,7 +1479,7 @@ lfc_init_new_entry(FileCacheEntry* entry, uint32 hash)
 		/* Can't add this chunk - we don't have the space for it */
 		hash_search_with_hash_value(lfc_hash, &entry->key, hash,
 									HASH_REMOVE, NULL);
-		lfc_prewarm_cancel = true; /* cancel prewarm if LFC limit is reached */
+		lfc_ctl->prewarm_canceled = true; /* cancel prewarm if LFC limit is reached */
 		return false;
 	}
 
@@ -1221,8 +1534,6 @@ lfc_prefetch(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 
 	int		chunk_offs = BLOCK_TO_CHUNK_OFF(blkno);
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return false;
 
@@ -1368,8 +1679,6 @@ lfc_writev(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 	uint32		entry_offset;
 	int			buf_offset = 0;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lfc_maybe_disabled())	/* fast exit if file cache is disabled */
 		return;
 
@@ -1588,6 +1897,7 @@ lfc_get_stats(size_t *num_entries)
 	return entries;
 }
 
+
 /*
  * Function returning data from the local file cache
  * relation node/tablespace/database/blocknum and access_counter
@@ -1691,15 +2001,15 @@ lfc_approximate_working_set_size_seconds(time_t duration, bool reset)
 }
 
 /*
- * Get metrics, for the built-in metrics exporter that's part of the
- * communicator process.
+ * Get metrics, for the built-in metrics exporter that's part of the communicator
+ * process.
  *
  * NB: This is called from a Rust tokio task inside the communicator process.
  * Acquiring lwlocks, elog(), allocating memory or anything else non-trivial
  * is strictly prohibited here!
  */
 struct LfcMetrics
-lfc_get_metrics_unsafe(void)
+callback_get_lfc_metrics_unsafe(void)
 {
 	struct LfcMetrics result = {
 		.lfc_cache_size_limit = (int64) lfc_size_limit * 1024 * 1024,
@@ -1720,3 +2030,82 @@ lfc_get_metrics_unsafe(void)
 
 	return result;
 }
+
+
+PG_FUNCTION_INFO_V1(get_local_cache_state);
+
+Datum
+get_local_cache_state(PG_FUNCTION_ARGS)
+{
+	size_t max_entries = PG_ARGISNULL(0) ? lfc_prewarm_limit : PG_GETARG_INT32(0);
+	FileCacheState* fcs = lfc_get_state(max_entries);
+	if (fcs != NULL)
+		PG_RETURN_BYTEA_P((bytea*)fcs);
+	else
+		PG_RETURN_NULL();
+}
+
+PG_FUNCTION_INFO_V1(prewarm_local_cache);
+
+Datum
+prewarm_local_cache(PG_FUNCTION_ARGS)
+{
+	bytea* state = PG_GETARG_BYTEA_PP(0);
+	uint32 n_workers =  PG_GETARG_INT32(1);
+	FileCacheState* fcs = (FileCacheState*)state;
+
+	lfc_prewarm(fcs, n_workers);
+
+	PG_RETURN_NULL();
+}
+
+PG_FUNCTION_INFO_V1(get_prewarm_info);
+
+Datum
+get_prewarm_info(PG_FUNCTION_ARGS)
+{
+	Datum		values[4];
+	bool		nulls[4];
+	TupleDesc	tupdesc;
+	uint32 prewarmed_pages = 0;
+	uint32 skipped_pages = 0;
+	uint32 active_workers = 0;
+	uint32 total_pages;
+	size_t n_workers;
+
+	if (lfc_size_limit == 0)
+		PG_RETURN_NULL();
+
+	LWLockAcquire(lfc_lock, LW_SHARED);
+	if (!lfc_ctl || lfc_ctl->n_prewarm_workers == 0)
+	{
+		LWLockRelease(lfc_lock);
+		PG_RETURN_NULL();
+	}
+	n_workers = lfc_ctl->n_prewarm_workers;
+	total_pages = lfc_ctl->total_prewarm_pages;
+	for (size_t i = 0; i < n_workers; i++)
+	{
+		PrewarmWorkerState* ws = &lfc_ctl->prewarm_workers[i];
+		prewarmed_pages += ws->prewarmed_pages;
+		skipped_pages += ws->skipped_pages;
+		active_workers += ws->completed != 0;
+	}
+	LWLockRelease(lfc_lock);
+
+	tupdesc = CreateTemplateTupleDesc(4);
+	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "total_pages", INT4OID, -1, 0);
+	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "prewarmed_pages", INT4OID, -1, 0);
+	TupleDescInitEntry(tupdesc, (AttrNumber) 3, "skipped_pages", INT4OID, -1, 0);
+	TupleDescInitEntry(tupdesc, (AttrNumber) 4, "active_workers", INT4OID, -1, 0);
+	tupdesc = BlessTupleDesc(tupdesc);
+
+	MemSet(nulls, 0, sizeof(nulls));
+
+	values[0] = Int32GetDatum(total_pages);
+	values[1] = Int32GetDatum(prewarmed_pages);
+	values[2] = Int32GetDatum(skipped_pages);
+	values[3] = Int32GetDatum(active_workers);
+
+	PG_RETURN_DATUM(HeapTupleGetDatum(heap_form_tuple(tupdesc, values, nulls)));
+}

pgxn/neon/file_cache.h

@@ -11,19 +11,21 @@
 #ifndef FILE_CACHE_h
 #define FILE_CACHE_h
 
-#include "lfc_prewarm.h"
-#include "neon.h"
-
 #include "neon_pgversioncompat.h"
 
+typedef struct FileCacheState
+{
+	int32		vl_len_;		/* varlena header (do not touch directly!) */
+	uint32		magic;
+	uint32		n_chunks;
+	uint32		n_pages;
+	uint16		chunk_size_log;
+	BufferTag	chunks[FLEXIBLE_ARRAY_MEMBER];
+	/* followed by bitmap */
+} FileCacheState;
+
 /* GUCs */
 extern bool lfc_store_prefetch_result;
-extern int	lfc_max_size;
-extern int	lfc_size_limit;
-extern char *lfc_path;
-
-extern bool lfc_do_prewarm;
-extern bool lfc_prewarm_cancel;
 
 /* functions for local file cache */
 extern void lfc_invalidate(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber nblocks);
@@ -42,12 +44,16 @@ extern int lfc_cache_containsv(NRelFileInfo rinfo, ForkNumber forkNum,
 extern void lfc_init(void);
 extern bool lfc_prefetch(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 						 const void* buffer, XLogRecPtr lsn);
-
 extern FileCacheState* lfc_get_state(size_t max_entries);
-extern LfcStatsEntry *lfc_get_stats(size_t *num_entries);
+extern void lfc_prewarm(FileCacheState* fcs, uint32 n_workers);
 
-struct LfcMetrics; /* defined in communicator_bindings.h */
-extern struct LfcMetrics lfc_get_metrics_unsafe(void);
+typedef struct LfcStatsEntry
+{
+	const char *metric_name;
+	bool		isnull;
+	uint64		value;
+} LfcStatsEntry;
+extern LfcStatsEntry *lfc_get_stats(size_t *num_entries);
 
 typedef struct
 {
@@ -63,6 +69,7 @@ extern LocalCachePagesRec *lfc_local_cache_pages(size_t *num_entries);
 
 extern int32 lfc_approximate_working_set_size_seconds(time_t duration, bool reset);
 
+
 static inline bool
 lfc_read(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 		 void *buffer)

pgxn/neon/lfc_prewarm.c

@@ -1,671 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * lfc_prewarm.c
- *		Functions related to LFC prewarming
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *-------------------------------------------------------------------------
- */
-
-#include "postgres.h"
-
-#include "bitmap.h"
-#include "communicator.h"
-#include "communicator_new.h"
-#include "file_cache.h"
-#include "lfc_prewarm.h"
-#include "neon.h"
-#include "neon_utils.h"
-#include "pagestore_client.h"
-
-#include "funcapi.h"
-#include "miscadmin.h"
-#include "postmaster/bgworker.h"
-#include "storage/dsm.h"
-#include "tcop/tcopprot.h"
-#include "utils/timestamp.h"
-
-#define MAX_PREWARM_WORKERS 8
-
-typedef struct PrewarmWorkerState
-{
-	uint32		prewarmed_pages;
-	uint32		skipped_pages;
-	TimestampTz completed;
-} PrewarmWorkerState;
-
-typedef struct PrewarmControl
-{
-	/* -1 when not using workers, 0 when no prewarm has been performed */
-	size_t		n_prewarm_workers;
-	size_t		total_prewarm_pages;
-	bool		prewarm_active;
-	bool		prewarm_canceled;
-
-	/* These are used in the non-worker mode */
-	uint32		prewarmed_pages;
-	uint32		skipped_pages;
-	TimestampTz completed;
-
-	/* These are used with workers */
-	PrewarmWorkerState prewarm_workers[MAX_PREWARM_WORKERS];
-	dsm_handle	prewarm_lfc_state_handle;
-	size_t		prewarm_batch;
-	size_t		n_prewarm_entries;
-} PrewarmControl;
-
-static PrewarmControl *prewarm_ctl;
-
-static int	lfc_prewarm_limit;
-static int	lfc_prewarm_batch;
-
-static LWLockId prewarm_lock;
-
-bool AmPrewarmWorker;
-
-static void lfc_prewarm_with_workers(FileCacheState *fcs, uint32 n_workers);
-static void lfc_prewarm_with_async_requests(FileCacheState *fcs);
-PGDLLEXPORT void lfc_prewarm_main(Datum main_arg);
-
-void
-pg_init_prewarm(void)
-{
-	DefineCustomIntVariable("neon.file_cache_prewarm_limit",
-							"Maximal number of prewarmed chunks",
-							NULL,
-							&lfc_prewarm_limit,
-							INT_MAX,	/* no limit by default */
-							0,
-							INT_MAX,
-							PGC_SIGHUP,
-							0,
-							NULL,
-							NULL,
-							NULL);
-
-	DefineCustomIntVariable("neon.file_cache_prewarm_batch",
-							"Number of pages retrivied by prewarm from page server",
-							NULL,
-							&lfc_prewarm_batch,
-							64,
-							1,
-							INT_MAX,
-							PGC_SIGHUP,
-							0,
-							NULL,
-							NULL,
-							NULL);
-}
-
-static size_t
-PrewarmShmemSize(void)
-{
-	return sizeof(PrewarmControl);
-}
-
-void
-PrewarmShmemRequest(void)
-{
-	RequestAddinShmemSpace(PrewarmShmemSize());
-	RequestNamedLWLockTranche("prewarm_lock", 1);
-}
-
-void
-PrewarmShmemInit(void)
-{
-	bool		found;
-
-	prewarm_ctl = (PrewarmControl *) ShmemInitStruct("Prewarmer shmem state",
-								PrewarmShmemSize(),
-								&found);
-	if (!found)
-	{
-		/* it's zeroed already */
-
-		prewarm_lock = (LWLockId) GetNamedLWLockTranche("prewarm_lock");
-	}
-}
-
-static void
-validate_fcs(FileCacheState *fcs)
-{
-	size_t fcs_size;
-#if 0
-	size_t fcs_chunk_size_log;
-#endif
-
-	if (fcs->magic != FILE_CACHE_STATE_MAGIC)
-	{
-		elog(ERROR, "LFC: Invalid file cache state magic: %X", fcs->magic);
-	}
-
-	fcs_size = VARSIZE(fcs);
-	if (FILE_CACHE_STATE_SIZE(fcs) != fcs_size)
-	{
-		elog(ERROR, "LFC: Invalid file cache state size: %u vs. %u", (unsigned)FILE_CACHE_STATE_SIZE(fcs), VARSIZE(fcs));
-	}
-
-	/* FIXME */
-#if 0
-	fcs_chunk_size_log = fcs->chunk_size_log;
-	if (fcs_chunk_size_log > MAX_BLOCKS_PER_CHUNK_LOG)
-	{
-		elog(ERROR, "LFC: Invalid chunk size log: %u", fcs->chunk_size_log);
-	}
-#endif
-}
-
-/*
- * Prewarm LFC cache to the specified state. It uses lfc_prefetch function to
- * load prewarmed page without hoilding shared buffer lock and avoid race
- * conditions with other backends.
- */
-void
-lfc_prewarm_with_workers(FileCacheState *fcs, uint32 n_workers)
-{
-	size_t n_entries;
-	size_t prewarm_batch = Min(lfc_prewarm_batch, readahead_buffer_size);
-	size_t fcs_size = VARSIZE(fcs);
-	dsm_segment *seg;
-	BackgroundWorkerHandle* bgw_handle[MAX_PREWARM_WORKERS];
-
-	Assert(!neon_use_communicator_worker);
-
-	if (prewarm_batch == 0 || lfc_prewarm_limit == 0 || n_workers == 0)
-	{
-		elog(LOG, "LFC: prewarm is disabled");
-		return;
-	}
-
-	if (n_workers > MAX_PREWARM_WORKERS)
-	{
-		elog(ERROR, "LFC: too many prewarm workers, maximum is %d", MAX_PREWARM_WORKERS);
-	}
-
-	if (fcs == NULL || fcs->n_chunks == 0)
-	{
-		elog(LOG, "LFC: nothing to prewarm");
-		return;
-	}
-
-	n_entries = Min(fcs->n_chunks, lfc_prewarm_limit);
-	Assert(n_entries != 0);
-
-	LWLockAcquire(prewarm_lock, LW_EXCLUSIVE);
-
-	/* Do not prewarm more entries than LFC limit */
-	/* FIXME */
-#if 0
-	if (prewarm_ctl->limit <= prewarm_ctl->size)
-	{
-		elog(LOG, "LFC: skip prewarm because LFC is already filled");
-		LWLockRelease(prewarm_lock);
-		return;
-	}
-#endif
-	
-	if (prewarm_ctl->prewarm_active)
-	{
-		LWLockRelease(prewarm_lock);
-		elog(ERROR, "LFC: skip prewarm because another prewarm is still active");
-	}
-	prewarm_ctl->n_prewarm_entries = n_entries;
-	prewarm_ctl->n_prewarm_workers = n_workers;
-	prewarm_ctl->prewarm_active = true;
-	prewarm_ctl->prewarm_canceled = false;
-	prewarm_ctl->prewarm_batch = prewarm_batch;
-	memset(prewarm_ctl->prewarm_workers, 0, n_workers*sizeof(PrewarmWorkerState));
-
-	/* Calculate total number of pages to be prewarmed */
-	prewarm_ctl->total_prewarm_pages = fcs->n_pages;
-
-	LWLockRelease(prewarm_lock);
-
-	seg = dsm_create(fcs_size, 0);
-	memcpy(dsm_segment_address(seg), fcs, fcs_size);
-	prewarm_ctl->prewarm_lfc_state_handle = dsm_segment_handle(seg);
-
-	/* Spawn background workers */
-	for (uint32 i = 0; i < n_workers; i++)
-	{
-		BackgroundWorker worker = {0};
-
-		worker.bgw_flags = BGWORKER_SHMEM_ACCESS;
-		worker.bgw_start_time = BgWorkerStart_ConsistentState;
-		worker.bgw_restart_time = BGW_NEVER_RESTART;
-		strcpy(worker.bgw_library_name, "neon");
-		strcpy(worker.bgw_function_name, "lfc_prewarm_main");
-		snprintf(worker.bgw_name, BGW_MAXLEN, "LFC prewarm worker %d", i+1);
-		strcpy(worker.bgw_type, "LFC prewarm worker");
-		worker.bgw_main_arg = Int32GetDatum(i);
-		/* must set notify PID to wait for shutdown */
-		worker.bgw_notify_pid = MyProcPid;
-
-		if (!RegisterDynamicBackgroundWorker(&worker, &bgw_handle[i]))
-		{
-			ereport(LOG,
-					(errcode(ERRCODE_INSUFFICIENT_RESOURCES),
-					 errmsg("LFC: registering dynamic bgworker prewarm failed"),
-					 errhint("Consider increasing the configuration parameter \"%s\".", "max_worker_processes")));
-			n_workers = i;
-			prewarm_ctl->prewarm_canceled = true;
-			break;
-		}
-	}
-
-	for (uint32 i = 0; i < n_workers; i++)
-	{
-		bool interrupted;
-		do
-		{
-			interrupted = false;
-			PG_TRY();
-			{
-				BgwHandleStatus status = WaitForBackgroundWorkerShutdown(bgw_handle[i]);
-				if (status != BGWH_STOPPED && status != BGWH_POSTMASTER_DIED)
-				{
-					elog(LOG, "LFC: Unexpected status of prewarm worker termination: %d", status);
-				}
-			}
-			PG_CATCH();
-			{
-				elog(LOG, "LFC: cancel prewarm");
-				prewarm_ctl->prewarm_canceled = true;
-				interrupted = true;
-			}
-			PG_END_TRY();
-		} while (interrupted);
-
-		if (!prewarm_ctl->prewarm_workers[i].completed)
-		{
-			/* Background worker doesn't set completion time: it means that it was abnormally terminated */
-			elog(LOG, "LFC: prewarm worker %d failed", i+1);
-			/* Set completion time to prevent get_prewarm_info from considering this worker as active */
-			prewarm_ctl->prewarm_workers[i].completed = GetCurrentTimestamp();
-		}
-	}
-	dsm_detach(seg);
-
-	LWLockAcquire(prewarm_lock, LW_EXCLUSIVE);
-	prewarm_ctl->prewarm_active = false;
-	LWLockRelease(prewarm_lock);
-}
-
-
-void
-lfc_prewarm_main(Datum main_arg)
-{
-	size_t snd_idx = 0, rcv_idx = 0;
-	size_t n_sent = 0, n_received = 0;
-	size_t fcs_chunk_size_log;
-	size_t max_prefetch_pages;
-	size_t prewarm_batch;
-	size_t n_workers;
-	dsm_segment *seg;
-	FileCacheState* fcs;
-	uint8* bitmap;
-	BufferTag tag;
-	PrewarmWorkerState* ws;
-	uint32 worker_id = DatumGetInt32(main_arg);
-
-	Assert(!neon_use_communicator_worker);
-
-	AmPrewarmWorker = true;
-
-	pqsignal(SIGTERM, die);
-	BackgroundWorkerUnblockSignals();
-
-	seg = dsm_attach(prewarm_ctl->prewarm_lfc_state_handle);
-	if (seg == NULL)
-		ereport(ERROR,
-				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
-				 errmsg("could not map dynamic shared memory segment")));
-
-	fcs = (FileCacheState*) dsm_segment_address(seg);
-	prewarm_batch = prewarm_ctl->prewarm_batch;
-	fcs_chunk_size_log = fcs->chunk_size_log;
-	n_workers = prewarm_ctl->n_prewarm_workers;
-	max_prefetch_pages = prewarm_ctl->n_prewarm_entries << fcs_chunk_size_log;
-	ws = &prewarm_ctl->prewarm_workers[worker_id];
-	bitmap = FILE_CACHE_STATE_BITMAP(fcs);
-
-	/* enable prefetch in LFC */
-	lfc_store_prefetch_result = true;
-	lfc_do_prewarm = true; /* Flag for lfc_prefetch preventing replacement of existed entries if LFC cache is full */
-
-	elog(LOG, "LFC: worker %d start prewarming", worker_id);
-	while (!prewarm_ctl->prewarm_canceled)
-	{
-		if (snd_idx < max_prefetch_pages)
-		{
-			if ((snd_idx >> fcs_chunk_size_log) % n_workers != worker_id)
-			{
-				/* If there are multiple workers, split chunks between them */
-				snd_idx += 1 << fcs_chunk_size_log;
-			}
-			else
-			{
-				if (BITMAP_ISSET(bitmap, snd_idx))
-				{
-					tag = fcs->chunks[snd_idx >> fcs_chunk_size_log];
-					tag.blockNum += snd_idx & ((1 << fcs_chunk_size_log) - 1);
-
-					if (!BufferTagIsValid(&tag))
-						elog(ERROR, "LFC: Invalid buffer tag: %u", tag.blockNum);
-
-					if (!lfc_cache_contains(BufTagGetNRelFileInfo(tag), tag.forkNum, tag.blockNum))
-					{
-						(void) communicator_prefetch_register_bufferv(tag, NULL, 1, NULL);
-						n_sent += 1;
-					}
-					else
-					{
-						ws->skipped_pages += 1;
-						BITMAP_CLR(bitmap, snd_idx);
-					}
-				}
-				snd_idx += 1;
-			}
-		}
-		if (n_sent >= n_received + prewarm_batch || snd_idx == max_prefetch_pages)
-		{
-			if (n_received == n_sent && snd_idx == max_prefetch_pages)
-			{
-				break;
-			}
-			if ((rcv_idx >> fcs_chunk_size_log) % n_workers != worker_id)
-			{
-				/* Skip chunks processed by other workers */
-				rcv_idx += 1 << fcs_chunk_size_log;
-				continue;
-			}
-
-			/* Locate next block to prefetch */
-			while (!BITMAP_ISSET(bitmap, rcv_idx))
-			{
-				rcv_idx += 1;
-			}
-			tag = fcs->chunks[rcv_idx >> fcs_chunk_size_log];
-			tag.blockNum += rcv_idx & ((1 << fcs_chunk_size_log) - 1);
-			if (communicator_prefetch_receive(tag))
-			{
-				ws->prewarmed_pages += 1;
-			}
-			else
-			{
-				ws->skipped_pages += 1;
-			}
-			rcv_idx += 1;
-			n_received += 1;
-		}
-	}
-	/* No need to perform prefetch cleanup here because prewarm worker will be terminated and
-	 * connection to PS dropped just after return from this function.
-	 */
-	Assert(n_sent == n_received || prewarm_ctl->prewarm_canceled);
-	elog(LOG, "LFC: worker %d complete prewarming: loaded %ld pages", worker_id, (long)n_received);
-	prewarm_ctl->prewarm_workers[worker_id].completed = GetCurrentTimestamp();
-}
-
-/*
- * Prewarm LFC cache to the specified state. Uses the new communicator
- *
- * FIXME: Is there a race condition because we're not holding Postgres
- * buffer manager locks?
- */
-static void
-lfc_prewarm_with_async_requests(FileCacheState *fcs)
-{
-	size_t n_entries;
-	uint8	   *bitmap;
-	uint64		bitno;
-	int			blocks_per_chunk;
-
-	Assert(neon_use_communicator_worker);
-
-	if (lfc_prewarm_limit == 0)
-	{
-		elog(LOG, "LFC: prewarm is disabled");
-		return;
-	}
-
-	if (fcs == NULL || fcs->n_chunks == 0)
-	{
-		elog(LOG, "LFC: nothing to prewarm");
-		return;
-	}
-
-	n_entries = Min(fcs->n_chunks, lfc_prewarm_limit);
-	Assert(n_entries != 0);
-
-	PG_TRY();
-	{
-		LWLockAcquire(prewarm_lock, LW_EXCLUSIVE);
-
-		/* Do not prewarm more entries than LFC limit */
-		/* FIXME */
-#if 0
-		if (prewarm_ctl->limit <= prewarm_ctl->size)
-		{
-			elog(LOG, "LFC: skip prewarm because LFC is already filled");
-			LWLockRelease(prewarm_lock);
-			return;
-		}
-#endif
-
-		if (prewarm_ctl->prewarm_active)
-		{
-			LWLockRelease(prewarm_lock);
-			elog(ERROR, "LFC: skip prewarm because another prewarm is still active");
-		}
-		prewarm_ctl->n_prewarm_entries = n_entries;
-		prewarm_ctl->n_prewarm_workers = -1;
-		prewarm_ctl->prewarm_active = true;
-		prewarm_ctl->prewarm_canceled = false;
-
-		/* Calculate total number of pages to be prewarmed */
-		prewarm_ctl->total_prewarm_pages = fcs->n_pages;
-
-		LWLockRelease(prewarm_lock);
-
-		elog(LOG, "LFC: start prewarming");
-		lfc_do_prewarm = true;
-		lfc_prewarm_cancel = false;
-
-		bitmap = FILE_CACHE_STATE_BITMAP(fcs);
-
-		blocks_per_chunk = 1 << fcs->chunk_size_log;
-
-		bitno = 0;
-		for (uint32 chunkno = 0; chunkno < fcs->n_chunks; chunkno++)
-		{
-			BufferTag *chunk_tag = &fcs->chunks[chunkno];
-			BlockNumber request_startblkno = InvalidBlockNumber;
-			BlockNumber request_endblkno;
-
-			if (!BufferTagIsValid(chunk_tag))
-				elog(ERROR, "LFC: Invalid buffer tag: %u", chunk_tag->blockNum);
-
-			if (lfc_prewarm_cancel)
-			{
-				prewarm_ctl->prewarm_canceled = true;
-				break;
-			}
-
-			/* take next chunk */
-			for (int j = 0; j < blocks_per_chunk; j++)
-			{
-				BlockNumber blkno = chunk_tag->blockNum + j;
-
-				if (BITMAP_ISSET(bitmap, bitno))
-				{
-					if (request_startblkno != InvalidBlockNumber)
-					{
-						if (request_endblkno == blkno)
-						{
-							/* append this block to the request */
-							request_endblkno++;
-						}
-						else
-						{
-							/* flush this request, and start new one */
-							communicator_new_prefetch_register_bufferv(
-								BufTagGetNRelFileInfo(*chunk_tag),
-								chunk_tag->forkNum,
-								request_startblkno,
-								request_endblkno - request_startblkno
-								);
-							request_startblkno = blkno;
-							request_endblkno = blkno + 1;
-						}
-					}
-					else
-					{
-						/* flush this request, if any, and start new one */
-						if (request_startblkno != InvalidBlockNumber)
-						{
-							communicator_new_prefetch_register_bufferv(
-								BufTagGetNRelFileInfo(*chunk_tag),
-								chunk_tag->forkNum,
-								request_startblkno,
-								request_endblkno - request_startblkno
-								);
-						}
-						request_startblkno = blkno;
-						request_endblkno = blkno + 1;
-					}
-					prewarm_ctl->prewarmed_pages += 1;
-				}
-				bitno++;
-			}
-
-			/* flush this request */
-			communicator_new_prefetch_register_bufferv(
-				BufTagGetNRelFileInfo(*chunk_tag),
-				chunk_tag->forkNum,
-				request_startblkno,
-				request_endblkno - request_startblkno
-				);
-			request_startblkno = request_endblkno = InvalidBlockNumber;
-		}
-
-		elog(LOG, "LFC: complete prewarming: loaded %lu pages", (unsigned long) prewarm_ctl->prewarmed_pages);
-		prewarm_ctl->completed = GetCurrentTimestamp();
-
-		LWLockAcquire(prewarm_lock, LW_EXCLUSIVE);
-		prewarm_ctl->prewarm_active = false;
-		LWLockRelease(prewarm_lock);
-	}
-	PG_CATCH();
-	{
-		elog(LOG, "LFC: cancel prewarm");
-		prewarm_ctl->prewarm_canceled = true;
-		prewarm_ctl->prewarm_active = false;
-	}
-	PG_END_TRY();
-}
-
-PG_FUNCTION_INFO_V1(get_local_cache_state);
-
-Datum
-get_local_cache_state(PG_FUNCTION_ARGS)
-{
-	size_t max_entries = PG_ARGISNULL(0) ? lfc_prewarm_limit : PG_GETARG_INT32(0);
-	FileCacheState* fcs;
-
-	if (neon_use_communicator_worker)
-		fcs = communicator_new_get_lfc_state(max_entries);
-	else
-		fcs = lfc_get_state(max_entries);
-
-	if (fcs != NULL)
-		PG_RETURN_BYTEA_P((bytea*)fcs);
-	else
-		PG_RETURN_NULL();
-}
-
-PG_FUNCTION_INFO_V1(prewarm_local_cache);
-
-Datum
-prewarm_local_cache(PG_FUNCTION_ARGS)
-{
-	bytea* state = PG_GETARG_BYTEA_PP(0);
-	uint32 n_workers =  PG_GETARG_INT32(1);
-	FileCacheState* fcs;
-
-	fcs = (FileCacheState *)state;
-	validate_fcs(fcs);
-
-	if (neon_use_communicator_worker)
-		lfc_prewarm_with_async_requests(fcs);
-	else
-		lfc_prewarm_with_workers(fcs, n_workers);
-
-	PG_RETURN_NULL();
-}
-
-PG_FUNCTION_INFO_V1(get_prewarm_info);
-
-Datum
-get_prewarm_info(PG_FUNCTION_ARGS)
-{
-	Datum		values[4];
-	bool		nulls[4];
-	TupleDesc	tupdesc;
-	uint32		prewarmed_pages = 0;
-	uint32		skipped_pages = 0;
-	uint32		active_workers = 0;
-	uint32		total_pages;
-
-	if (lfc_size_limit == 0)
-		PG_RETURN_NULL();
-
-	LWLockAcquire(prewarm_lock, LW_SHARED);
-	if (!prewarm_ctl || prewarm_ctl->n_prewarm_workers == 0)
-	{
-		LWLockRelease(prewarm_lock);
-		PG_RETURN_NULL();
-	}
-
-	if (prewarm_ctl->n_prewarm_workers == -1)
-	{
-		total_pages = prewarm_ctl->total_prewarm_pages;
-		prewarmed_pages = prewarm_ctl->prewarmed_pages;
-		skipped_pages = prewarm_ctl->skipped_pages;
-		active_workers = 1;
-	}
-	else
-	{
-		size_t		n_workers;
-
-		n_workers = prewarm_ctl->n_prewarm_workers;
-		total_pages = prewarm_ctl->total_prewarm_pages;
-		for (size_t i = 0; i < n_workers; i++)
-		{
-			PrewarmWorkerState *ws = &prewarm_ctl->prewarm_workers[i];
-
-			prewarmed_pages += ws->prewarmed_pages;
-			skipped_pages += ws->skipped_pages;
-			active_workers += ws->completed != 0;
-		}
-	}
-	LWLockRelease(prewarm_lock);
-
-	tupdesc = CreateTemplateTupleDesc(4);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 1, "total_pages", INT4OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 2, "prewarmed_pages", INT4OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 3, "skipped_pages", INT4OID, -1, 0);
-	TupleDescInitEntry(tupdesc, (AttrNumber) 4, "active_workers", INT4OID, -1, 0);
-	tupdesc = BlessTupleDesc(tupdesc);
-
-	MemSet(nulls, 0, sizeof(nulls));
-
-	values[0] = Int32GetDatum(total_pages);
-	values[1] = Int32GetDatum(prewarmed_pages);
-	values[2] = Int32GetDatum(skipped_pages);
-	values[3] = Int32GetDatum(active_workers);
-
-	PG_RETURN_DATUM(HeapTupleGetDatum(heap_form_tuple(tupdesc, values, nulls)));
-}

pgxn/neon/lfc_prewarm.h

@@ -1,39 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * lfc_prewarm.h
- *	  Local File Cache prewarmer
- *
- * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- *-------------------------------------------------------------------------
- */
-#ifndef LFC_PREWARM_H
-#define LFC_PREWARM_H
-
-#include "storage/buf_internals.h"
-
-typedef struct FileCacheState
-{
-	int32		vl_len_;		/* varlena header (do not touch directly!) */
-	uint32		magic;
-	uint32		n_chunks;
-	uint32		n_pages;
-	uint16		chunk_size_log;
-	BufferTag	chunks[FLEXIBLE_ARRAY_MEMBER];
-	/* followed by bitmap */
-} FileCacheState;
-
-#define FILE_CACHE_STATE_MAGIC 0xfcfcfcfc
-
-#define FILE_CACHE_STATE_BITMAP(fcs)	((uint8*)&(fcs)->chunks[(fcs)->n_chunks])
-#define FILE_CACHE_STATE_SIZE_FOR_CHUNKS(n_chunks, blocks_per_chunk)	(sizeof(FileCacheState) + (n_chunks)*sizeof(BufferTag) + (((n_chunks) * blocks_per_chunk)+7)/8)
-#define FILE_CACHE_STATE_SIZE(fcs)		(sizeof(FileCacheState) + (fcs->n_chunks)*sizeof(BufferTag) + (((fcs->n_chunks) << fcs->chunk_size_log)+7)/8)
-
-extern void pg_init_prewarm(void);
-extern void PrewarmShmemRequest(void);
-extern void PrewarmShmemInit(void);
-
-#endif							/* LFC_PREWARM_H */
-
-

pgxn/neon/libpagestore.c

@@ -72,7 +72,6 @@ char	   *neon_branch_id;
 char	   *neon_endpoint_id;
 int32		max_cluster_size;
 char	   *pageserver_connstring;
-char	   *pageserver_grpc_urls;
 char	   *neon_auth_token;
 
 int			readahead_buffer_size = 128;
@@ -82,7 +81,7 @@ int         neon_protocol_version = 3;
 
 static int	neon_compute_mode = 0;
 static int	max_reconnect_attempts = 60;
-int		neon_stripe_size;
+static int	stripe_size;
 static int	max_sockets;
 
 static int pageserver_response_log_timeout = 10000;
@@ -93,6 +92,13 @@ static int	conf_refresh_reconnect_attempt_threshold = 16;
 // Hadron: timeout for refresh errors (1 minute)
 static uint64 	kRefreshErrorTimeoutUSec = 1 * USECS_PER_MINUTE;
 
+typedef struct
+{
+	char		connstring[MAX_SHARDS][MAX_PAGESERVER_CONNSTRING_SIZE];
+	size_t		num_shards;
+	size_t		stripe_size;
+} ShardMap;
+
 /*
  * PagestoreShmemState is kept in shared memory. It contains the connection
  * strings for each shard.
@@ -181,8 +187,6 @@ static void pageserver_disconnect_shard(shardno_t shard_no);
 // HADRON
 shardno_t get_num_shards(void);
 
-static void AssignShardMap(const char *newval);
-
 static bool
 PagestoreShmemIsValid(void)
 {
@@ -196,8 +200,8 @@ PagestoreShmemIsValid(void)
  * not valid, returns false. The contents of *result are undefined in
  * that case, and must not be relied on.
  */
-bool
-parse_shard_map(const char *connstr, ShardMap *result)
+static bool
+ParseShardMap(const char *connstr, ShardMap *result)
 {
 	const char *p;
 	int			nshards = 0;
@@ -242,31 +246,24 @@ parse_shard_map(const char *connstr, ShardMap *result)
 	if (result)
 	{
 		result->num_shards = nshards;
-		result->stripe_size = neon_stripe_size;
+		result->stripe_size = stripe_size;
 	}
 
 	return true;
 }
 
-/* GUC hooks for neon.pageserver_connstring */
 static bool
 CheckPageserverConnstring(char **newval, void **extra, GucSource source)
 {
 	char	   *p = *newval;
 
-	return parse_shard_map(p, NULL);
+	return ParseShardMap(p, NULL);
 }
 
 static void
 AssignPageserverConnstring(const char *newval, void *extra)
 {
-	/*
-	 * 'neon.pageserver_connstring' is ignored if the new communicator is used.
-	 * In that case, the shard map is loaded from 'neon.pageserver_grpc_urls'
-	 * instead, and that happens in the communicator process only.
-	 */
-	if (neon_use_communicator_worker)
-		return;
+	ShardMap	shard_map;
 
 	/*
 	 * Only postmaster updates the copy in shared memory.
@@ -274,29 +271,11 @@ AssignPageserverConnstring(const char *newval, void *extra)
 	if (!PagestoreShmemIsValid() || IsUnderPostmaster)
 		return;
 
-	AssignShardMap(newval);
-}
-
-
-/* GUC hooks for neon.pageserver_connstring */
-static bool
-CheckPageserverGrpcUrls(char **newval, void **extra, GucSource source)
-{
-	char	   *p = *newval;
-
-	return parse_shard_map(p, NULL);
-}
-
-static void
-AssignShardMap(const char *newval)
-{
-	ShardMap	shard_map;
-
-	if (!parse_shard_map(newval, &shard_map))
+	if (!ParseShardMap(newval, &shard_map))
 	{
 		/*
 		 * shouldn't happen, because we already checked the value in
-		 * CheckPageserverConnstring/CheckPageserverGrpcUrls
+		 * CheckPageserverConnstring
 		 */
 		elog(ERROR, "could not parse shard map");
 	}
@@ -315,27 +294,6 @@ AssignShardMap(const char *newval)
 	}
 }
 
-/*
- * Set the 'num_shards' variable in shared memory.
- *
- * This is only used with the new communicator. The new communicator doesn't
- * use the shard_map in shared memory, except for the shard count, which is
- * needed by get_num_shards() calls in the walproposer. This is called to set
- * that. This is only called from the communicator process, at process startup
- * or if the configuration is reloaded.
- */
-void
-AssignNumShards(shardno_t num_shards)
-{
-	Assert(neon_use_communicator_worker);
-
-	pg_atomic_add_fetch_u64(&pagestore_shared->begin_update_counter, 1);
-	pg_write_barrier();
-	pagestore_shared->shard_map.num_shards = num_shards;
-	pg_write_barrier();
-	pg_atomic_add_fetch_u64(&pagestore_shared->end_update_counter, 1);
-}
-
 /* BEGIN_HADRON */
 /**
  * Return the total number of shards seen in the shard map.
@@ -439,10 +397,10 @@ get_shard_number(BufferTag *tag)
 
 #if PG_MAJORVERSION_NUM < 16
 	hash = murmurhash32(tag->rnode.relNode);
-	hash = hash_combine(hash, murmurhash32(tag->blockNum / neon_stripe_size));
+	hash = hash_combine(hash, murmurhash32(tag->blockNum / stripe_size));
 #else
 	hash = murmurhash32(tag->relNumber);
-	hash = hash_combine(hash, murmurhash32(tag->blockNum / neon_stripe_size));
+	hash = hash_combine(hash, murmurhash32(tag->blockNum / stripe_size));
 #endif
 
 	return hash % n_shards;
@@ -1520,15 +1478,6 @@ pg_init_libpagestore(void)
 							   0,	/* no flags required */
 							   CheckPageserverConnstring, AssignPageserverConnstring, NULL);
 
-	DefineCustomStringVariable("neon.pageserver_grpc_urls",
-							   "list of gRPC URLs for the page servers",
-							   NULL,
-							   &pageserver_grpc_urls,
-							   "",
-							   PGC_SIGHUP,
-							   0,	/* no flags required */
-							   CheckPageserverGrpcUrls, NULL, NULL);
-
 	DefineCustomStringVariable("neon.timeline_id",
 							   "Neon timeline_id the server is running on",
 							   NULL,
@@ -1575,7 +1524,7 @@ pg_init_libpagestore(void)
 	DefineCustomIntVariable("neon.stripe_size",
 							"sharding stripe size",
 							NULL,
-							&neon_stripe_size,
+							&stripe_size,
 							2048, 1, INT_MAX,
 							PGC_SIGHUP,
 							GUC_UNIT_BLOCKS,
@@ -1694,7 +1643,7 @@ pg_init_libpagestore(void)
 	if (neon_auth_token)
 		neon_log(LOG, "using storage auth token from NEON_AUTH_TOKEN environment variable");
 
-	if (pageserver_connstring[0] || pageserver_grpc_urls[0])
+	if (pageserver_connstring[0])
 	{
 		neon_log(PageStoreTrace, "set neon_smgr hook");
 		smgr_hook = smgr_neon;

pgxn/neon/neon.c

@@ -21,7 +21,6 @@
 #include "replication/logicallauncher.h"
 #include "replication/slot.h"
 #include "replication/walsender.h"
-#include "storage/ipc.h"
 #include "storage/proc.h"
 #include "storage/ipc.h"
 #include "funcapi.h"
@@ -32,7 +31,6 @@
 #include "utils/guc_tables.h"
 
 #include "communicator.h"
-#include "communicator_new.h"
 #include "communicator_process.h"
 #include "extension_server.h"
 #include "file_cache.h"
@@ -475,16 +473,6 @@ _PG_init(void)
 	load_file("$libdir/neon_rmgr", false);
 #endif
 
-	DefineCustomBoolVariable(
-							"neon.use_communicator_worker",
-							"Uses the communicator worker implementation",
-							NULL,
-							&neon_use_communicator_worker,
-							true,
-							PGC_POSTMASTER,
-							0,
-							NULL, NULL, NULL);
-
 	if (lakebase_mode) {
 		prev_emit_log_hook = emit_log_hook;
 		emit_log_hook = DatabricksSqlErrorHookImpl;
@@ -524,14 +512,12 @@ _PG_init(void)
 	pg_init_libpagestore();
 	relsize_hash_init();
 	lfc_init();
-	pg_init_prewarm();
 	pg_init_walproposer();
-	pg_init_lwlsncache();
+	init_lwlsncache();
 
 	pg_init_communicator_process();
 
 	pg_init_communicator();
-
 	Custom_XLogReaderRoutines = NeonOnDemandXLogReaderRoutines;
 
 	InitUnstableExtensionsSupport();
@@ -737,10 +723,7 @@ approximate_working_set_size_seconds(PG_FUNCTION_ARGS)
 
 	duration = PG_ARGISNULL(0) ? (time_t) -1 : PG_GETARG_INT32(0);
 
-	if (neon_use_communicator_worker)
-		dc = communicator_new_approximate_working_set_size_seconds(duration, false);
-	else
-		dc = lfc_approximate_working_set_size_seconds(duration, false);
+	dc = lfc_approximate_working_set_size_seconds(duration, false);
 	if (dc < 0)
 		PG_RETURN_NULL();
 	else
@@ -753,10 +736,7 @@ approximate_working_set_size(PG_FUNCTION_ARGS)
 	bool		reset = PG_GETARG_BOOL(0);
 	int32		dc;
 
-	if (neon_use_communicator_worker)
-		dc = communicator_new_approximate_working_set_size_seconds(-1, reset);
-	else
-		dc = lfc_approximate_working_set_size_seconds(-1, reset);
+	dc = lfc_approximate_working_set_size_seconds(-1, reset);
 	if (dc < 0)
 		PG_RETURN_NULL();
 	else
@@ -774,10 +754,7 @@ neon_get_lfc_stats(PG_FUNCTION_ARGS)
 	InitMaterializedSRF(fcinfo, 0);
 
 	/* lfc_get_stats() does all the heavy lifting */
-	if (neon_use_communicator_worker)
-		entries = communicator_new_lfc_get_stats(&num_entries);
-	else
-		entries = lfc_get_stats(&num_entries);
+	entries = lfc_get_stats(&num_entries);
 
 	/* Convert the LfcStatsEntrys to a result set */
 	for (size_t i = 0; i < num_entries; i++)
@@ -851,13 +828,11 @@ neon_shmem_request_hook(void)
 #endif
 
 	LfcShmemRequest();
-	PrewarmShmemRequest();
 	NeonPerfCountersShmemRequest();
 	PagestoreShmemRequest();
 	RelsizeCacheShmemRequest();
 	WalproposerShmemRequest();
 	LwLsnCacheShmemRequest();
-	CommunicatorNewShmemRequest();
 }
 
 
@@ -875,7 +850,6 @@ neon_shmem_startup_hook(void)
 	LWLockAcquire(AddinShmemInitLock, LW_EXCLUSIVE);
 
 	LfcShmemInit();
-	PrewarmShmemInit();
 	NeonPerfCountersShmemInit();
 	if (lakebase_mode) {
 		DatabricksMetricsShmemInit();
@@ -884,7 +858,6 @@ neon_shmem_startup_hook(void)
 	RelsizeCacheShmemInit();
 	WalproposerShmemInit();
 	LwLsnCacheShmemInit();
-	CommunicatorNewShmemInit();
 
 #if PG_MAJORVERSION_NUM >= 17
 	WAIT_EVENT_NEON_LFC_MAINTENANCE = WaitEventExtensionNew("Neon/FileCache_Maintenance");

pgxn/neon/neon.h

@@ -85,11 +85,5 @@ extern void WalproposerShmemInit(void);
 extern void LwLsnCacheShmemInit(void);
 extern void NeonPerfCountersShmemInit(void);
 
-typedef struct LfcStatsEntry
-{
-	const char *metric_name;
-	bool		isnull;
-	uint64		value;
-} LfcStatsEntry;
 
 #endif							/* NEON_H */

pgxn/neon/neon_lwlsncache.c

@@ -85,54 +85,12 @@ static set_lwlsn_db_hook_type prev_set_lwlsn_db_hook = NULL;
 static void neon_set_max_lwlsn(XLogRecPtr lsn);
 
 void
-pg_init_lwlsncache(void)
+init_lwlsncache(void)
 {
 	if (!process_shared_preload_libraries_in_progress)
 		ereport(ERROR, errcode(ERRCODE_INTERNAL_ERROR), errmsg("Loading of shared preload libraries is not in progress. Exiting"));
 	
 	lwlc_register_gucs();
-}
-
-
-void
-LwLsnCacheShmemRequest(void)
-{
-	Size		requested_size;
-
-	if (neon_use_communicator_worker)
-		return;
-
-	requested_size = sizeof(LwLsnCacheCtl);
-	requested_size += hash_estimate_size(lwlsn_cache_size, sizeof(LastWrittenLsnCacheEntry));
-
-	RequestAddinShmemSpace(requested_size);
-}
-
-void
-LwLsnCacheShmemInit(void)
-{
-	static HASHCTL info;
-	bool		found;
-
-	if (neon_use_communicator_worker)
-		return;
-
-	Assert(lwlsn_cache_size > 0);
-
-	info.keysize = sizeof(BufferTag);
-	info.entrysize = sizeof(LastWrittenLsnCacheEntry);
-	lastWrittenLsnCache = ShmemInitHash("last_written_lsn_cache",
-										lwlsn_cache_size, lwlsn_cache_size,
-										&info,
-										HASH_ELEM | HASH_BLOBS);
-	LwLsnCache = ShmemInitStruct("neon/LwLsnCacheCtl", sizeof(LwLsnCacheCtl), &found);
-	// Now set the size in the struct
-	LwLsnCache->lastWrittenLsnCacheSize = lwlsn_cache_size;
-	if (found) {
-		return;
-	}
-	dlist_init(&LwLsnCache->lastWrittenLsnLRU);
-    LwLsnCache->maxLastWrittenLsn = GetRedoRecPtr();
 
 	prev_set_lwlsn_block_range_hook = set_lwlsn_block_range_hook;
 	set_lwlsn_block_range_hook = neon_set_lwlsn_block_range;
@@ -148,6 +106,41 @@ LwLsnCacheShmemInit(void)
 	set_lwlsn_db_hook = neon_set_lwlsn_db;
 }
 
+
+void
+LwLsnCacheShmemRequest(void)
+{
+	Size requested_size = sizeof(LwLsnCacheCtl);
+
+	requested_size += hash_estimate_size(lwlsn_cache_size, sizeof(LastWrittenLsnCacheEntry));
+
+	RequestAddinShmemSpace(requested_size);
+}
+
+void
+LwLsnCacheShmemInit(void)
+{
+	static HASHCTL info;
+	bool found;
+	if (lwlsn_cache_size > 0)
+	{
+		info.keysize = sizeof(BufferTag);
+		info.entrysize = sizeof(LastWrittenLsnCacheEntry);
+		lastWrittenLsnCache = ShmemInitHash("last_written_lsn_cache",
+			lwlsn_cache_size, lwlsn_cache_size,
+										&info,
+										HASH_ELEM | HASH_BLOBS);
+		LwLsnCache = ShmemInitStruct("neon/LwLsnCacheCtl", sizeof(LwLsnCacheCtl), &found);
+		// Now set the size in the struct
+		LwLsnCache->lastWrittenLsnCacheSize = lwlsn_cache_size;
+		if (found) {
+			return;
+		}
+	}
+	dlist_init(&LwLsnCache->lastWrittenLsnLRU);
+    LwLsnCache->maxLastWrittenLsn = GetRedoRecPtr();
+}
+
 /*
  * neon_get_lwlsn -- Returns maximal LSN of written page.
  * It returns an upper bound for the last written LSN of a given page,
@@ -162,7 +155,6 @@ neon_get_lwlsn(NRelFileInfo rlocator, ForkNumber forknum, BlockNumber blkno)
 	XLogRecPtr lsn;
 	LastWrittenLsnCacheEntry* entry;
 
-	Assert(!neon_use_communicator_worker);
 	Assert(LwLsnCache->lastWrittenLsnCacheSize != 0);
 
 	LWLockAcquire(LastWrittenLsnLock, LW_SHARED);
@@ -215,10 +207,7 @@ neon_get_lwlsn(NRelFileInfo rlocator, ForkNumber forknum, BlockNumber blkno)
 	return lsn;
 }
 
-static void
-neon_set_max_lwlsn(XLogRecPtr lsn)
-{
-	Assert(!neon_use_communicator_worker);
+static void neon_set_max_lwlsn(XLogRecPtr lsn) {
 	LWLockAcquire(LastWrittenLsnLock, LW_EXCLUSIVE);
 	LwLsnCache->maxLastWrittenLsn = lsn;
 	LWLockRelease(LastWrittenLsnLock);
@@ -239,7 +228,6 @@ neon_get_lwlsn_v(NRelFileInfo relfilenode, ForkNumber forknum,
 	LastWrittenLsnCacheEntry* entry;
 	XLogRecPtr lsn;
 
-	Assert(!neon_use_communicator_worker);
 	Assert(LwLsnCache->lastWrittenLsnCacheSize != 0);
 	Assert(nblocks > 0);
 	Assert(PointerIsValid(lsns));
@@ -388,8 +376,6 @@ SetLastWrittenLSNForBlockRangeInternal(XLogRecPtr lsn,
 XLogRecPtr
 neon_set_lwlsn_block_range(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumber forknum, BlockNumber from, BlockNumber n_blocks)
 {
-	Assert(!neon_use_communicator_worker);
-
 	if (lsn == InvalidXLogRecPtr || n_blocks == 0 || LwLsnCache->lastWrittenLsnCacheSize == 0)
 		return lsn;
 
@@ -426,8 +412,6 @@ neon_set_lwlsn_block_v(const XLogRecPtr *lsns, NRelFileInfo relfilenode,
 	Oid dbOid = NInfoGetDbOid(relfilenode);
 	Oid relNumber = NInfoGetRelNumber(relfilenode);
 
-	Assert(!neon_use_communicator_worker);
-
 	if (lsns == NULL || nblocks == 0 || LwLsnCache->lastWrittenLsnCacheSize == 0 ||
 		NInfoGetRelNumber(relfilenode) == InvalidOid)
 		return InvalidXLogRecPtr;
@@ -485,7 +469,6 @@ neon_set_lwlsn_block_v(const XLogRecPtr *lsns, NRelFileInfo relfilenode,
 XLogRecPtr
 neon_set_lwlsn_block(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumber forknum, BlockNumber blkno)
 {
-	Assert(!neon_use_communicator_worker);
 	return neon_set_lwlsn_block_range(lsn, rlocator, forknum, blkno, 1);
 }
 
@@ -495,7 +478,6 @@ neon_set_lwlsn_block(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumber forknum,
 XLogRecPtr
 neon_set_lwlsn_relation(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumber forknum)
 {
-	Assert(!neon_use_communicator_worker);
 	return neon_set_lwlsn_block(lsn, rlocator, forknum, REL_METADATA_PSEUDO_BLOCKNO);
 }
 
@@ -506,8 +488,6 @@ XLogRecPtr
 neon_set_lwlsn_db(XLogRecPtr lsn)
 {
 	NRelFileInfo dummyNode = {InvalidOid, InvalidOid, InvalidOid};
-
-	Assert(!neon_use_communicator_worker);
 	return neon_set_lwlsn_block(lsn, dummyNode, MAIN_FORKNUM, 0);
 }
 

pgxn/neon/neon_lwlsncache.h

@@ -3,7 +3,7 @@
 
 #include "neon_pgversioncompat.h"
 
-extern void pg_init_lwlsncache(void);
+void init_lwlsncache(void);
 
 /* Hooks */
 XLogRecPtr neon_get_lwlsn(NRelFileInfo rlocator, ForkNumber forknum, BlockNumber blkno);
@@ -14,4 +14,4 @@ XLogRecPtr neon_set_lwlsn_block(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumbe
 XLogRecPtr neon_set_lwlsn_relation(XLogRecPtr lsn, NRelFileInfo rlocator, ForkNumber forknum);
 XLogRecPtr neon_set_lwlsn_db(XLogRecPtr lsn);
 
-#endif /* NEON_LWLSNCACHE_H */
+#endif /* NEON_LWLSNCACHE_H */

pgxn/neon/pagestore_client.h

@@ -237,27 +237,15 @@ extern void prefetch_on_ps_disconnect(void);
 extern page_server_api *page_server;
 
 extern char *pageserver_connstring;
-extern char *pageserver_grpc_urls;
 extern int	flush_every_n_requests;
 extern int	readahead_buffer_size;
 extern char *neon_timeline;
 extern char *neon_tenant;
 extern int32 max_cluster_size;
 extern int  neon_protocol_version;
-extern int	neon_stripe_size;
 
-typedef struct
-{
-	char		connstring[MAX_SHARDS][MAX_PAGESERVER_CONNSTRING_SIZE];
-	size_t		num_shards;
-	size_t		stripe_size;
-} ShardMap;
-
-extern bool parse_shard_map(const char *connstr, ShardMap *result);
 extern shardno_t get_shard_number(BufferTag* tag);
 
-extern void AssignNumShards(shardno_t num_shards);
-
 extern const f_smgr *smgr_neon(ProcNumber backend, NRelFileInfo rinfo);
 extern void smgr_init_neon(void);
 extern void readahead_buffer_resize(int newsize, void *extra);
@@ -302,7 +290,6 @@ extern int64 neon_dbsize(Oid dbNode);
 extern void neon_get_request_lsns(NRelFileInfo rinfo, ForkNumber forknum,
 								  BlockNumber blkno, neon_request_lsns *output,
 								  BlockNumber nblocks);
-extern XLogRecPtr neon_get_write_lsn(void);
 
 /* utils for neon relsize cache */
 extern void relsize_hash_init(void);

pgxn/neon/pagestore_smgr.c

@@ -62,7 +62,6 @@
 
 #include "bitmap.h"
 #include "communicator.h"
-#include "communicator_new.h"
 #include "file_cache.h"
 #include "neon.h"
 #include "neon_lwlsncache.h"
@@ -302,7 +301,7 @@ neon_wallog_pagev(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 		 */
 		lsns[batch_size++] = lsn;
 
-		if (batch_size >= BLOCK_BATCH_SIZE && !neon_use_communicator_worker)
+		if (batch_size >= BLOCK_BATCH_SIZE)
 		{
 			neon_set_lwlsn_block_v(lsns, InfoFromSMgrRel(reln), forknum,
 									   batch_blockno,
@@ -312,7 +311,7 @@ neon_wallog_pagev(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 		}
 	}
 
-	if (batch_size != 0 && !neon_use_communicator_worker)
+	if (batch_size != 0)
 	{
 		neon_set_lwlsn_block_v(lsns, InfoFromSMgrRel(reln), forknum,
 								   batch_blockno,
@@ -437,17 +436,11 @@ neon_wallog_page(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum, co
 						forknum, LSN_FORMAT_ARGS(lsn))));
 	}
 
-	if (!neon_use_communicator_worker)
-	{
-		/*
-		 * Remember the LSN on this page. When we read the page again, we must
-		 * read the same or newer version of it.
-		 *
-		 * (With the new communicator, the caller will make a write-request
-		 * for this page, which updates the last-written LSN too)
-		 */
-		neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forknum, blocknum);
-	}
+	/*
+	 * Remember the LSN on this page. When we read the page again, we must
+	 * read the same or newer version of it.
+	 */
+	neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forknum, blocknum);
 }
 
 /*
@@ -504,60 +497,6 @@ nm_adjust_lsn(XLogRecPtr lsn)
 	return lsn;
 }
 
-/*
- * Get a LSN to use to stamp an operation like relation create or truncate.
- * On operations on individual pages we use the LSN of the page, but when
- * e.g. smgrcreate() is called, we have to do something else.
- */
-XLogRecPtr
-neon_get_write_lsn(void)
-{
-	XLogRecPtr	lsn;
-
-	if (RecoveryInProgress())
-	{
-		/*
-		 * FIXME: v14 doesn't have GetCurrentReplayRecPtr(). Options:
-		 * - add it in our fork
-		 * - store a magic value that means that you must use
-		 *   current latest possible LSN at the time that the request
-		 *   on this thing is made again (or some other recent enough
-		 *   lsn).
-		 */
-#if PG_VERSION_NUM >= 150000
-		lsn = GetCurrentReplayRecPtr(NULL);
-#else
-		lsn = GetXLogReplayRecPtr(NULL); /* FIXME: this is wrong, see above */
-#endif
-	}
-	else
-		lsn = GetXLogInsertRecPtr();
-
-	/*
-	 * If the insert LSN points to just after page header, round it down to
-	 * the beginning of the page, because the page header might not have been
-	 * inserted to the WAL yet, and if we tried to flush it, the WAL flushing
-	 * code gets upset.
-	 */
-	{
-		int			segoff;
-
-		segoff = XLogSegmentOffset(lsn, wal_segment_size);
-		if (segoff == SizeOfXLogLongPHD)
-		{
-			lsn = lsn - segoff;
-		}
-		else
-		{
-			int			offset = lsn % XLOG_BLCKSZ;
-
-			if (offset == SizeOfXLogShortPHD)
-				lsn = lsn - offset;
-		}
-	}
-
-	return lsn;
-}
 
 /*
  * Return LSN for requesting pages and number of blocks from page server
@@ -570,7 +509,6 @@ neon_get_request_lsns(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 {
 	XLogRecPtr	last_written_lsns[PG_IOV_MAX];
 
-	Assert(!neon_use_communicator_worker);
 	Assert(nblocks <= PG_IOV_MAX);
 
 	neon_get_lwlsn_v(rinfo, forknum, blkno, (int) nblocks, last_written_lsns);
@@ -802,6 +740,11 @@ neon_exists(SMgrRelation reln, ForkNumber forkNum)
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
+	if (get_cached_relsize(InfoFromSMgrRel(reln), forkNum, &n_blocks))
+	{
+		return true;
+	}
+
 	/*
 	 * \d+ on a view calls smgrexists with 0/0/0 relfilenode. The page server
 	 * will error out if you check that, because the whole dbdir for
@@ -825,20 +768,10 @@ neon_exists(SMgrRelation reln, ForkNumber forkNum)
 		return false;
 	}
 
-	if (neon_use_communicator_worker)
-		return communicator_new_rel_exists(InfoFromSMgrRel(reln), forkNum);
-	else
-	{
-		if (get_cached_relsize(InfoFromSMgrRel(reln), forkNum, &n_blocks))
-		{
-			return true;
-		}
+	neon_get_request_lsns(InfoFromSMgrRel(reln), forkNum,
+						  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
 
-		neon_get_request_lsns(InfoFromSMgrRel(reln), forkNum,
-							  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
-
-		return communicator_exists(InfoFromSMgrRel(reln), forkNum, &request_lsns);
-	}
+	return communicator_exists(InfoFromSMgrRel(reln), forkNum, &request_lsns);
 }
 
 /*
@@ -896,53 +829,16 @@ neon_create(SMgrRelation reln, ForkNumber forkNum, bool isRedo)
 	 * relation. Currently, we don't call SetLastWrittenLSN() when a new
 	 * relation created, so if we didn't remember the size in the relsize
 	 * cache, we might call smgrnblocks() on the newly-created relation before
-	 * the creation WAL record has been received by the page server.
-	 *
-	 * XXX: with the new communicator, similar considerations apply. However,
-	 * during replay, neon_get_write_lsn() returns the (end-)LSN of the record
-	 * that's being replayed, so we should not have the correctness issue
-	 * mentioned in previous paragraph.
+	 * the creation WAL record hass been received by the page server.
 	 */
-	if (neon_use_communicator_worker)
+	if (isRedo)
 	{
-		XLogRecPtr	lsn = neon_get_write_lsn();
-
-		if (isRedo)
-		{
-			/*
-			 * TODO: the protocol can check for existence and get the relsize
-			 * in one roundtrip. Add a similar call to the
-			 * backend<->communicator API. (The size is cached on the
-			 * rel_exists call, so this does only one roundtrip to the
-			 * pageserver, but two function calls and two cache lookups.)
-			 */
-			if (!communicator_new_rel_exists(InfoFromSMgrRel(reln), forkNum))
-			{
-				communicator_new_rel_create(InfoFromSMgrRel(reln), forkNum, lsn);
-				reln->smgr_cached_nblocks[forkNum] = 0;
-			}
-			else
-			{
-				BlockNumber nblocks;
-
-				nblocks = communicator_new_rel_nblocks(InfoFromSMgrRel(reln), forkNum);
-				reln->smgr_cached_nblocks[forkNum] = nblocks;
-			}
-		}
-		else
-			communicator_new_rel_create(InfoFromSMgrRel(reln), forkNum, lsn);
+		update_cached_relsize(InfoFromSMgrRel(reln), forkNum, 0);
+		get_cached_relsize(InfoFromSMgrRel(reln), forkNum,
+						   &reln->smgr_cached_nblocks[forkNum]);
 	}
 	else
-	{
-		if (isRedo)
-		{
-			update_cached_relsize(InfoFromSMgrRel(reln), forkNum, 0);
-			get_cached_relsize(InfoFromSMgrRel(reln), forkNum,
-							   &reln->smgr_cached_nblocks[forkNum]);
-		}
-		else
-			set_cached_relsize(InfoFromSMgrRel(reln), forkNum, 0);
-	}
+		set_cached_relsize(InfoFromSMgrRel(reln), forkNum, 0);
 
 	if (debug_compare_local)
 	{
@@ -978,17 +874,9 @@ neon_unlink(NRelFileInfoBackend rinfo, ForkNumber forkNum, bool isRedo)
 	 * unlink, it won't do any harm if the file doesn't exist.
 	 */
 	mdunlink(rinfo, forkNum, isRedo);
-
 	if (!NRelFileInfoBackendIsTemp(rinfo))
 	{
-		if (neon_use_communicator_worker)
-		{
-			XLogRecPtr	lsn = neon_get_write_lsn();
-
-			communicator_new_rel_unlink(InfoFromNInfoB(rinfo), forkNum, lsn);
-		}
-		else
-			forget_cached_relsize(InfoFromNInfoB(rinfo), forkNum);
+		forget_cached_relsize(InfoFromNInfoB(rinfo), forkNum);
 	}
 }
 
@@ -1011,7 +899,6 @@ neon_extend(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno,
 #endif
 {
 	XLogRecPtr	lsn;
-	bool		lsn_was_zero;
 	BlockNumber n_blocks = 0;
 
 	switch (reln->smgr_relpersistence)
@@ -1069,6 +956,7 @@ neon_extend(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno,
 		neon_wallog_page(reln, forkNum, n_blocks++, buffer, true);
 
 	neon_wallog_page(reln, forkNum, blkno, buffer, false);
+	set_cached_relsize(InfoFromSMgrRel(reln), forkNum, blkno + 1);
 
 	lsn = PageGetLSN((Page) buffer);
 	neon_log(SmgrTrace, "smgrextend called for %u/%u/%u.%u blk %u, page LSN: %X/%08X",
@@ -1076,6 +964,14 @@ neon_extend(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno,
 		 forkNum, blkno,
 		 (uint32) (lsn >> 32), (uint32) lsn);
 
+	lfc_write(InfoFromSMgrRel(reln), forkNum, blkno, buffer);
+
+	if (debug_compare_local)
+	{
+		if (IS_LOCAL_REL(reln))
+			mdextend(reln, forkNum, blkno, buffer, skipFsync);
+	}
+
 	/*
 	 * smgr_extend is often called with an all-zeroes page, so
 	 * lsn==InvalidXLogRecPtr. An smgr_write() call will come for the buffer
@@ -1083,51 +979,20 @@ neon_extend(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno,
 	 * it is eventually evicted from the buffer cache. But we need a valid LSN
 	 * to the relation metadata update now.
 	 */
-	lsn_was_zero = (lsn == InvalidXLogRecPtr);
-	if (lsn_was_zero)
+	if (lsn == InvalidXLogRecPtr)
+	{
 		lsn = GetXLogInsertRecPtr();
-
-	if (neon_use_communicator_worker)
-	{
-		communicator_new_rel_extend(InfoFromSMgrRel(reln), forkNum, blkno, (const void *) buffer, lsn);
-
-		if (debug_compare_local)
-		{
-			if (IS_LOCAL_REL(reln))
-				mdextend(reln, forkNum, blkno, buffer, skipFsync);
-		}
-	}
-	else
-	{
-		set_cached_relsize(InfoFromSMgrRel(reln), forkNum, blkno + 1);
-		lfc_write(InfoFromSMgrRel(reln), forkNum, blkno, buffer);
-
-		if (debug_compare_local)
-		{
-			if (IS_LOCAL_REL(reln))
-				mdextend(reln, forkNum, blkno, buffer, skipFsync);
-		}
-
-		/*
-		 * smgr_extend is often called with an all-zeroes page, so
-		 * lsn==InvalidXLogRecPtr. An smgr_write() call will come for the buffer
-		 * later, after it has been initialized with the real page contents, and
-		 * it is eventually evicted from the buffer cache. But we need a valid LSN
-		 * to the relation metadata update now.
-		 */
-		if (lsn_was_zero)
-			neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forkNum, blkno);
-		neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forkNum);
+		neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forkNum, blkno);
 	}
+	neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forkNum);
 }
 
 #if PG_MAJORVERSION_NUM >= 16
 static void
-neon_zeroextend(SMgrRelation reln, ForkNumber forkNum, BlockNumber start_block,
+neon_zeroextend(SMgrRelation reln, ForkNumber forkNum, BlockNumber blocknum,
 				int nblocks, bool skipFsync)
 {
 	const PGIOAlignedBlock buffer = {0};
-	BlockNumber blocknum = start_block;
 	int			remblocks = nblocks;
 	XLogRecPtr	lsn = 0;
 
@@ -1210,14 +1075,11 @@ neon_zeroextend(SMgrRelation reln, ForkNumber forkNum, BlockNumber start_block,
 
 		lsn = XLogInsert(RM_XLOG_ID, XLOG_FPI);
 
-		if (!neon_use_communicator_worker)
+		for (int i = 0; i < count; i++)
 		{
-			for (int i = 0; i < count; i++)
-			{
-				lfc_write(InfoFromSMgrRel(reln), forkNum, blocknum + i, buffer.data);
-				neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forkNum,
-									 blocknum + i);
-			}
+			lfc_write(InfoFromSMgrRel(reln), forkNum, blocknum + i, buffer.data);
+			neon_set_lwlsn_block(lsn, InfoFromSMgrRel(reln), forkNum,
+									  blocknum + i);
 		}
 
 		blocknum += count;
@@ -1226,15 +1088,8 @@ neon_zeroextend(SMgrRelation reln, ForkNumber forkNum, BlockNumber start_block,
 
 	Assert(lsn != 0);
 
-	if (neon_use_communicator_worker)
-	{
-		communicator_new_rel_zeroextend(InfoFromSMgrRel(reln), forkNum, start_block, nblocks, lsn);
-	}
-	else
-	{
-		neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forkNum);
-		set_cached_relsize(InfoFromSMgrRel(reln), forkNum, blocknum);
-	}
+	neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forkNum);
+	set_cached_relsize(InfoFromSMgrRel(reln), forkNum, blocknum);
 }
 #endif
 
@@ -1294,12 +1149,6 @@ neon_prefetch(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
-	if (neon_use_communicator_worker)
-	{
-		communicator_new_prefetch_register_bufferv(InfoFromSMgrRel(reln), forknum, blocknum, nblocks);
-		return false;
-	}
-
 	tag.spcOid = reln->smgr_rlocator.locator.spcOid;
 	tag.dbOid = reln->smgr_rlocator.locator.dbOid;
 	tag.relNumber = reln->smgr_rlocator.locator.relNumber;
@@ -1326,8 +1175,7 @@ neon_prefetch(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 		blocknum += iterblocks;
 	}
 
-	if (!neon_use_communicator_worker)
-		communicator_prefetch_pump_state();
+	communicator_prefetch_pump_state();
 
 	return false;
 }
@@ -1340,6 +1188,8 @@ neon_prefetch(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 static bool
 neon_prefetch(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum)
 {
+	BufferTag	tag;
+
 	switch (reln->smgr_relpersistence)
 	{
 		case 0:					/* probably shouldn't happen, but ignore it */
@@ -1354,25 +1204,17 @@ neon_prefetch(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum)
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
-	if (neon_use_communicator_worker)
-	{
-		communicator_new_prefetch_register_bufferv(InfoFromSMgrRel(reln), forknum, blocknum, 1);
-	}
-	else
-	{
-		BufferTag	tag;
+	if (lfc_cache_contains(InfoFromSMgrRel(reln), forknum, blocknum))
+		return false;
 
-		if (lfc_cache_contains(InfoFromSMgrRel(reln), forknum, blocknum))
-			return false;
+	tag.forkNum = forknum;
+	tag.blockNum = blocknum;
 
-		tag.forkNum = forknum;
-		tag.blockNum = blocknum;
+	CopyNRelFileInfoToBufTag(tag, InfoFromSMgrRel(reln));
 
-		CopyNRelFileInfoToBufTag(tag, InfoFromSMgrRel(reln));
-		communicator_prefetch_register_bufferv(tag, NULL, 1, NULL);
+	communicator_prefetch_register_bufferv(tag, NULL, 1, NULL);
 
-		communicator_prefetch_pump_state();
-	}
+	communicator_prefetch_pump_state();
 
 	return false;
 }
@@ -1416,8 +1258,7 @@ neon_writeback(SMgrRelation reln, ForkNumber forknum,
 	 */
 	neon_log(SmgrTrace, "writeback noop");
 
-	if (!neon_use_communicator_worker)
-		communicator_prefetch_pump_state();
+	communicator_prefetch_pump_state();
 
 	if (debug_compare_local)
 	{
@@ -1434,14 +1275,7 @@ void
 neon_read_at_lsn(NRelFileInfo rinfo, ForkNumber forkNum, BlockNumber blkno,
 				 neon_request_lsns request_lsns, void *buffer)
 {
-	if (neon_use_communicator_worker)
-	{
-		// FIXME: request_lsns is ignored. That affects the neon_test_utils callers.
-		// Add the capability to specify the LSNs explicitly, for the sake of neon_test_utils ?
-		communicator_new_read_at_lsn_uncached(rinfo, forkNum, blkno, buffer, request_lsns.request_lsn, request_lsns.not_modified_since);
-	}
-	else
-		communicator_read_at_lsnv(rinfo, forkNum, blkno, &request_lsns, &buffer, 1, NULL);
+	communicator_read_at_lsnv(rinfo, forkNum, blkno, &request_lsns, &buffer, 1, NULL);
 }
 
 static void
@@ -1567,55 +1401,47 @@ neon_read(SMgrRelation reln, ForkNumber forkNum, BlockNumber blkno, void *buffer
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
-	if (neon_use_communicator_worker)
+	/* Try to read PS results if they are available */
+	communicator_prefetch_pump_state();
+
+	neon_get_request_lsns(InfoFromSMgrRel(reln), forkNum, blkno, &request_lsns, 1);
+
+	present = 0;
+	bufferp = buffer;
+	if (communicator_prefetch_lookupv(InfoFromSMgrRel(reln), forkNum, blkno, &request_lsns, 1, &bufferp, &present))
 	{
-		communicator_new_readv(InfoFromSMgrRel(reln), forkNum, blkno,
-							   (void *) &buffer, 1);
+		/* Prefetch hit */
+		if (debug_compare_local >= DEBUG_COMPARE_LOCAL_PREFETCH)
+		{
+			compare_with_local(reln, forkNum, blkno, buffer, request_lsns.request_lsn);
+		}
+		if (debug_compare_local <= DEBUG_COMPARE_LOCAL_PREFETCH)
+		{
+			return;
+		}
 	}
-	else
+
+	/* Try to read from local file cache */
+	if (lfc_read(InfoFromSMgrRel(reln), forkNum, blkno, buffer))
 	{
-		/* Try to read PS results if they are available */
-		communicator_prefetch_pump_state();
-
-		neon_get_request_lsns(InfoFromSMgrRel(reln), forkNum, blkno, &request_lsns, 1);
-
-		present = 0;
-		bufferp = buffer;
-		if (communicator_prefetch_lookupv(InfoFromSMgrRel(reln), forkNum, blkno, &request_lsns, 1, &bufferp, &present))
+		MyNeonCounters->file_cache_hits_total++;
+		if (debug_compare_local >= DEBUG_COMPARE_LOCAL_LFC)
 		{
-			/* Prefetch hit */
-			if (debug_compare_local >= DEBUG_COMPARE_LOCAL_PREFETCH)
-			{
-				compare_with_local(reln, forkNum, blkno, buffer, request_lsns.request_lsn);
-			}
-			if (debug_compare_local <= DEBUG_COMPARE_LOCAL_PREFETCH)
-			{
-				return;
-			}
+			compare_with_local(reln, forkNum, blkno, buffer, request_lsns.request_lsn);
 		}
-
-		/* Try to read from local file cache */
-		if (lfc_read(InfoFromSMgrRel(reln), forkNum, blkno, buffer))
+		if (debug_compare_local <= DEBUG_COMPARE_LOCAL_LFC)
 		{
-			MyNeonCounters->file_cache_hits_total++;
-			if (debug_compare_local >= DEBUG_COMPARE_LOCAL_LFC)
-			{
-				compare_with_local(reln, forkNum, blkno, buffer, request_lsns.request_lsn);
-			}
-			if (debug_compare_local <= DEBUG_COMPARE_LOCAL_LFC)
-			{
-				return;
-			}
+			return;
 		}
-
-		neon_read_at_lsn(InfoFromSMgrRel(reln), forkNum, blkno, request_lsns, buffer);
-
-		/*
-		 * Try to receive prefetch results once again just to make sure we don't leave the smgr code while the OS might still have buffered bytes.
-		 */
-		communicator_prefetch_pump_state();
 	}
 
+	neon_read_at_lsn(InfoFromSMgrRel(reln), forkNum, blkno, request_lsns, buffer);
+
+	/*
+	 * Try to receive prefetch results once again just to make sure we don't leave the smgr code while the OS might still have buffered bytes.
+	 */
+	communicator_prefetch_pump_state();
+
 	if (debug_compare_local)
 	{
 		compare_with_local(reln, forkNum, blkno, buffer, request_lsns.request_lsn);
@@ -1678,67 +1504,59 @@ neon_readv(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum,
 				 nblocks, PG_IOV_MAX);
 
 	/* Try to read PS results if they are available */
-	if (!neon_use_communicator_worker)
-		communicator_prefetch_pump_state();
+	communicator_prefetch_pump_state();
+
+	neon_get_request_lsns(InfoFromSMgrRel(reln), forknum, blocknum,
+						  request_lsns, nblocks);
 
 	memset(read_pages, 0, sizeof(read_pages));
 
-	if (neon_use_communicator_worker)
+	prefetch_result = communicator_prefetch_lookupv(InfoFromSMgrRel(reln), forknum,
+													blocknum, request_lsns, nblocks,
+													buffers, read_pages);
+
+	if (debug_compare_local >= DEBUG_COMPARE_LOCAL_PREFETCH)
 	{
-		communicator_new_readv(InfoFromSMgrRel(reln), forknum, blocknum,
-							   buffers, nblocks);
+		compare_with_localv(reln, forknum, blocknum, buffers, nblocks, request_lsns, read_pages);
 	}
-	else
+	if (debug_compare_local <= DEBUG_COMPARE_LOCAL_PREFETCH && prefetch_result == nblocks)
 	{
-		neon_get_request_lsns(InfoFromSMgrRel(reln), forknum, blocknum,
-							  request_lsns, nblocks);
-
-		prefetch_result = communicator_prefetch_lookupv(InfoFromSMgrRel(reln), forknum,
-														blocknum, request_lsns, nblocks,
-														buffers, read_pages);
-
-		if (debug_compare_local >= DEBUG_COMPARE_LOCAL_PREFETCH)
-		{
-			compare_with_localv(reln, forknum, blocknum, buffers, nblocks, request_lsns, read_pages);
-		}
-		if (debug_compare_local <= DEBUG_COMPARE_LOCAL_PREFETCH && prefetch_result == nblocks)
-		{
-			return;
-		}
-		if (debug_compare_local > DEBUG_COMPARE_LOCAL_PREFETCH)
-		{
-			memset(read_pages, 0, sizeof(read_pages));
-		}
-
-		/* Try to read from local file cache */
-		lfc_result = lfc_readv_select(InfoFromSMgrRel(reln), forknum, blocknum, buffers,
-									  nblocks, read_pages);
-
-		if (lfc_result > 0)
-			MyNeonCounters->file_cache_hits_total += lfc_result;
-
-		if (debug_compare_local >= DEBUG_COMPARE_LOCAL_LFC)
-		{
-			compare_with_localv(reln, forknum, blocknum, buffers, nblocks, request_lsns, read_pages);
-		}
-		if (debug_compare_local <= DEBUG_COMPARE_LOCAL_LFC && prefetch_result + lfc_result == nblocks)
-		{
-			/* Read all blocks from LFC, so we're done */
-			return;
-		}
-		if (debug_compare_local > DEBUG_COMPARE_LOCAL_LFC)
-		{
-			memset(read_pages, 0, sizeof(read_pages));
-		}
-
-		communicator_read_at_lsnv(InfoFromSMgrRel(reln), forknum, blocknum, request_lsns,
-								  buffers, nblocks, read_pages);
-
-		/*
-		 * Try to receive prefetch results once again just to make sure we don't leave the smgr code while the OS might still have buffered bytes.
-		 */
-		communicator_prefetch_pump_state();
+		return;
 	}
+	if (debug_compare_local > DEBUG_COMPARE_LOCAL_PREFETCH)
+	{
+		memset(read_pages, 0, sizeof(read_pages));
+	}
+
+
+	/* Try to read from local file cache */
+	lfc_result = lfc_readv_select(InfoFromSMgrRel(reln), forknum, blocknum, buffers,
+								  nblocks, read_pages);
+
+	if (lfc_result > 0)
+		MyNeonCounters->file_cache_hits_total += lfc_result;
+
+	if (debug_compare_local >= DEBUG_COMPARE_LOCAL_LFC)
+	{
+		compare_with_localv(reln, forknum, blocknum, buffers, nblocks, request_lsns, read_pages);
+	}
+	if (debug_compare_local <= DEBUG_COMPARE_LOCAL_LFC && prefetch_result + lfc_result == nblocks)
+	{
+		/* Read all blocks from LFC, so we're done */
+		return;
+	}
+	if (debug_compare_local > DEBUG_COMPARE_LOCAL_LFC)
+	{
+		memset(read_pages, 0, sizeof(read_pages));
+	}
+
+	communicator_read_at_lsnv(InfoFromSMgrRel(reln), forknum, blocknum, request_lsns,
+							  buffers, nblocks, read_pages);
+
+	/*
+	 * Try to receive prefetch results once again just to make sure we don't leave the smgr code while the OS might still have buffered bytes.
+	 */
+	communicator_prefetch_pump_state();
 
 	if (debug_compare_local)
 	{
@@ -1839,16 +1657,9 @@ neon_write(SMgrRelation reln, ForkNumber forknum, BlockNumber blocknum, const vo
 		 forknum, blocknum,
 		 (uint32) (lsn >> 32), (uint32) lsn);
 
-	if (neon_use_communicator_worker)
-	{
-		communicator_new_write_page(InfoFromSMgrRel(reln), forknum, blocknum, buffer, lsn);
-	}
-	else
-	{
-		lfc_write(InfoFromSMgrRel(reln), forknum, blocknum, buffer);
+	lfc_write(InfoFromSMgrRel(reln), forknum, blocknum, buffer);
 
-		communicator_prefetch_pump_state();
-	}
+	communicator_prefetch_pump_state();
 
 	if (debug_compare_local)
 	{
@@ -1909,21 +1720,9 @@ neon_writev(SMgrRelation reln, ForkNumber forknum, BlockNumber blkno,
 
 	neon_wallog_pagev(reln, forknum, blkno, nblocks, (const char **) buffers, false);
 
-	if (neon_use_communicator_worker)
-	{
-		for (int i = 0; i < nblocks; i++)
-		{
-			XLogRecPtr lsn = PageGetLSN((Page) buffers[i]);
+	lfc_writev(InfoFromSMgrRel(reln), forknum, blkno, buffers, nblocks);
 
-			communicator_new_write_page(InfoFromSMgrRel(reln), forknum, blkno + i, buffers[i], lsn);
-		}
-	}
-	else
-	{
-		lfc_writev(InfoFromSMgrRel(reln), forknum, blkno, buffers, nblocks);
-
-		communicator_prefetch_pump_state();
-	}
+	communicator_prefetch_pump_state();
 
 	if (debug_compare_local)
 	{
@@ -1964,26 +1763,19 @@ neon_nblocks(SMgrRelation reln, ForkNumber forknum)
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
-	if (neon_use_communicator_worker)
+	if (get_cached_relsize(InfoFromSMgrRel(reln), forknum, &n_blocks))
 	{
-		n_blocks = communicator_new_rel_nblocks(InfoFromSMgrRel(reln), forknum);
+		neon_log(SmgrTrace, "cached nblocks for %u/%u/%u.%u: %u blocks",
+			 RelFileInfoFmt(InfoFromSMgrRel(reln)),
+			 forknum, n_blocks);
+		return n_blocks;
 	}
-	else
-	{
-		if (get_cached_relsize(InfoFromSMgrRel(reln), forknum, &n_blocks))
-		{
-			neon_log(SmgrTrace, "cached nblocks for %u/%u/%u.%u: %u blocks",
-					 RelFileInfoFmt(InfoFromSMgrRel(reln)),
-					 forknum, n_blocks);
-			return n_blocks;
-		}
 
-		neon_get_request_lsns(InfoFromSMgrRel(reln), forknum,
-							  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
+	neon_get_request_lsns(InfoFromSMgrRel(reln), forknum,
+						  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
 
-		n_blocks = communicator_nblocks(InfoFromSMgrRel(reln), forknum, &request_lsns);
-		update_cached_relsize(InfoFromSMgrRel(reln), forknum, n_blocks);
-	}
+	n_blocks = communicator_nblocks(InfoFromSMgrRel(reln), forknum, &request_lsns);
+	update_cached_relsize(InfoFromSMgrRel(reln), forknum, n_blocks);
 
 	neon_log(SmgrTrace, "neon_nblocks: rel %u/%u/%u fork %u (request LSN %X/%08X): %u blocks",
 			 RelFileInfoFmt(InfoFromSMgrRel(reln)),
@@ -2004,17 +1796,10 @@ neon_dbsize(Oid dbNode)
 	neon_request_lsns request_lsns;
 	NRelFileInfo dummy_node = {0};
 
-	if (neon_use_communicator_worker)
-	{
-		db_size = communicator_new_dbsize(dbNode);
-	}
-	else
-	{
-		neon_get_request_lsns(dummy_node, MAIN_FORKNUM,
-							  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
+	neon_get_request_lsns(dummy_node, MAIN_FORKNUM,
+						  REL_METADATA_PSEUDO_BLOCKNO, &request_lsns, 1);
 
-		db_size = communicator_dbsize(dbNode, &request_lsns);
-	}
+	db_size = communicator_dbsize(dbNode, &request_lsns);
 
 	neon_log(SmgrTrace, "neon_dbsize: db %u (request LSN %X/%08X): %ld bytes",
 			 dbNode, LSN_FORMAT_ARGS(request_lsns.effective_request_lsn), db_size);
@@ -2028,6 +1813,8 @@ neon_dbsize(Oid dbNode)
 static void
 neon_truncate(SMgrRelation reln, ForkNumber forknum, BlockNumber old_blocks, BlockNumber nblocks)
 {
+	XLogRecPtr	lsn;
+
 	switch (reln->smgr_relpersistence)
 	{
 		case 0:
@@ -2051,45 +1838,34 @@ neon_truncate(SMgrRelation reln, ForkNumber forknum, BlockNumber old_blocks, Blo
 			neon_log(ERROR, "unknown relpersistence '%c'", reln->smgr_relpersistence);
 	}
 
-	if (neon_use_communicator_worker)
-	{
-		XLogRecPtr	lsn = neon_get_write_lsn();
+	set_cached_relsize(InfoFromSMgrRel(reln), forknum, nblocks);
 
-		communicator_new_rel_truncate(InfoFromSMgrRel(reln), forknum, nblocks, lsn);
-	}
-	else
-	{
-		XLogRecPtr	lsn;
+	/*
+	 * Truncating a relation drops all its buffers from the buffer cache
+	 * without calling smgrwrite() on them. But we must account for that in
+	 * our tracking of last-written-LSN all the same: any future smgrnblocks()
+	 * request must return the new size after the truncation. We don't know
+	 * what the LSN of the truncation record was, so be conservative and use
+	 * the most recently inserted WAL record's LSN.
+	 */
+	lsn = GetXLogInsertRecPtr();
+	lsn = nm_adjust_lsn(lsn);
 
-		set_cached_relsize(InfoFromSMgrRel(reln), forknum, nblocks);
+	/*
+	 * Flush it, too. We don't actually care about it here, but let's uphold
+	 * the invariant that last-written LSN <= flush LSN.
+	 */
+	XLogFlush(lsn);
 
-		/*
-		 * Truncating a relation drops all its buffers from the buffer cache
-		 * without calling smgrwrite() on them. But we must account for that in
-		 * our tracking of last-written-LSN all the same: any future smgrnblocks()
-		 * request must return the new size after the truncation. We don't know
-		 * what the LSN of the truncation record was, so be conservative and use
-		 * the most recently inserted WAL record's LSN.
-		 */
-		lsn = GetXLogInsertRecPtr();
-		lsn = nm_adjust_lsn(lsn);
-
-		/*
-		 * Flush it, too. We don't actually care about it here, but let's uphold
-		 * the invariant that last-written LSN <= flush LSN.
-		 */
-		XLogFlush(lsn);
-
-		/*
-		 * Truncate may affect several chunks of relations. So we should either
-		 * update last written LSN for all of them, or update LSN for "dummy"
-		 * metadata block. Second approach seems more efficient. If the relation
-		 * is extended again later, the extension will update the last-written LSN
-		 * for the extended pages, so there's no harm in leaving behind obsolete
-		 * entries for the truncated chunks.
-		 */
-		neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forknum);
-	}
+	/*
+	 * Truncate may affect several chunks of relations. So we should either
+	 * update last written LSN for all of them, or update LSN for "dummy"
+	 * metadata block. Second approach seems more efficient. If the relation
+	 * is extended again later, the extension will update the last-written LSN
+	 * for the extended pages, so there's no harm in leaving behind obsolete
+	 * entries for the truncated chunks.
+	 */
+	neon_set_lwlsn_relation(lsn, InfoFromSMgrRel(reln), forknum);
 
 	if (debug_compare_local)
 	{
@@ -2132,8 +1908,7 @@ neon_immedsync(SMgrRelation reln, ForkNumber forknum)
 
 	neon_log(SmgrTrace, "[NEON_SMGR] immedsync noop");
 
-	if (!neon_use_communicator_worker)
-		communicator_prefetch_pump_state();
+	communicator_prefetch_pump_state();
 
 	if (debug_compare_local)
 	{
@@ -2319,15 +2094,12 @@ neon_end_unlogged_build(SMgrRelation reln)
 		nblocks = mdnblocks(reln, MAIN_FORKNUM);
 		recptr = GetXLogInsertRecPtr();
 
-		if (!neon_use_communicator_worker)
-		{
-			neon_set_lwlsn_block_range(recptr,
-									   InfoFromNInfoB(rinfob),
-									   MAIN_FORKNUM, 0, nblocks);
-			neon_set_lwlsn_relation(recptr,
-									InfoFromNInfoB(rinfob),
-									MAIN_FORKNUM);
-		}
+		neon_set_lwlsn_block_range(recptr,
+								   InfoFromNInfoB(rinfob),
+								   MAIN_FORKNUM, 0, nblocks);
+		neon_set_lwlsn_relation(recptr,
+								InfoFromNInfoB(rinfob),
+								MAIN_FORKNUM);
 
 		/* Remove local copy */
 		for (int forknum = 0; forknum <= MAX_FORKNUM; forknum++)
@@ -2336,15 +2108,8 @@ neon_end_unlogged_build(SMgrRelation reln)
 				 RelFileInfoFmt(InfoFromNInfoB(rinfob)),
 				 forknum);
 
-			if (neon_use_communicator_worker)
-			{
-				communicator_new_update_cached_rel_size(InfoFromSMgrRel(reln), forknum, nblocks, recptr);
-			}
-			else
-			{
-				forget_cached_relsize(InfoFromNInfoB(rinfob), forknum);
-				lfc_invalidate(InfoFromNInfoB(rinfob), forknum, nblocks);
-			}
+			forget_cached_relsize(InfoFromNInfoB(rinfob), forknum);
+			lfc_invalidate(InfoFromNInfoB(rinfob), forknum, nblocks);
 
 			mdclose(reln, forknum);
 			if (!debug_compare_local)
@@ -2412,10 +2177,7 @@ neon_read_slru_segment(SMgrRelation reln, const char* path, int segno, void* buf
 	request_lsns.not_modified_since = not_modified_since;
 	request_lsns.effective_request_lsn = request_lsn;
 
-	if (neon_use_communicator_worker)
-		n_blocks = communicator_new_read_slru_segment(kind, (uint32_t)segno, &request_lsns, path);
-	else
-		n_blocks = communicator_read_slru_segment(kind, segno, &request_lsns, buffer);
+	n_blocks = communicator_read_slru_segment(kind, segno, &request_lsns, buffer);
 
 	return n_blocks;
 }
@@ -2452,8 +2214,7 @@ AtEOXact_neon(XactEvent event, void *arg)
 			}
 			break;
 	}
-	if (!neon_use_communicator_worker)
-		communicator_reconfigure_timeout_if_needed();
+	communicator_reconfigure_timeout_if_needed();
 }
 
 static const struct f_smgr neon_smgr =
@@ -2511,10 +2272,7 @@ smgr_init_neon(void)
 
 	smgr_init_standard();
 	neon_init();
-	if (neon_use_communicator_worker)
-		communicator_new_init();
-	else
-		communicator_init();
+	communicator_init();
 }
 
 
@@ -2526,16 +2284,6 @@ neon_extend_rel_size(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber blkno,
 	/* This is only used in WAL replay */
 	Assert(RecoveryInProgress());
 
-	if (neon_use_communicator_worker)
-	{
-		relsize = communicator_new_rel_nblocks(rinfo, forknum);
-
-		if (blkno >= relsize)
-			communicator_new_rel_zeroextend(rinfo, forknum, relsize, (blkno - relsize) + 1, end_recptr);
-
-		return;
-	}
-
 	/* Extend the relation if we know its size */
 	if (get_cached_relsize(rinfo, forknum, &relsize))
 	{
@@ -2690,27 +2438,18 @@ neon_redo_read_buffer_filter(XLogReaderState *record, uint8 block_id)
 	}
 
 	/*
-	 * We don't have the buffer in shared buffers. Check if it's in the LFC.
-	 * If it's not there either, update the lwLsn past this record.
+	 * we don't have the buffer in memory, update lwLsn past this record, also
+	 * evict page from file cache
 	 */
 	if (no_redo_needed)
 	{
-		bool		in_cache;
-
+		neon_set_lwlsn_block(end_recptr, rinfo, forknum, blkno);
 		/*
-		 * Redo changes if the page is present in the LFC.
+		 * Redo changes if page exists in LFC.
+		 * We should perform this check after assigning LwLSN to prevent
+		 * prefetching of some older version of the page by some other backend.
 		 */
-		if (neon_use_communicator_worker)
-		{
-			in_cache = communicator_new_update_lwlsn_for_block_if_not_cached(rinfo, forknum, blkno, end_recptr);
-		}
-		else
-		{
-			in_cache = lfc_cache_contains(rinfo, forknum, blkno);
-			neon_set_lwlsn_block(end_recptr, rinfo, forknum, blkno);
-		}
-
-		no_redo_needed = !in_cache;
+		no_redo_needed = !lfc_cache_contains(rinfo, forknum, blkno);
 	}
 
 	LWLockRelease(partitionLock);

pgxn/neon/relsize_cache.c

@@ -87,8 +87,6 @@ get_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber *size)
 {
 	bool		found = false;
 
-	Assert(!neon_use_communicator_worker);
-
 	if (relsize_hash_size > 0)
 	{
 		RelTag		tag;
@@ -120,8 +118,6 @@ get_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber *size)
 void
 set_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber size)
 {
-	Assert(!neon_use_communicator_worker);
-
 	if (relsize_hash_size > 0)
 	{
 		RelTag		tag;
@@ -170,8 +166,6 @@ set_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber size)
 void
 update_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber size)
 {
-	Assert(!neon_use_communicator_worker);
-
 	if (relsize_hash_size > 0)
 	{
 		RelTag		tag;
@@ -206,8 +200,6 @@ update_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum, BlockNumber size)
 void
 forget_cached_relsize(NRelFileInfo rinfo, ForkNumber forknum)
 {
-	Assert(!neon_use_communicator_worker);
-
 	if (relsize_hash_size > 0)
 	{
 		RelTag		tag;

proxy/src/serverless/rest.rs

@@ -5,12 +5,17 @@ use std::sync::Arc;
 
 use bytes::Bytes;
 use http::Method;
-use http::header::{AUTHORIZATION, CONTENT_TYPE, HOST};
+use http::header::{
+    ACCESS_CONTROL_ALLOW_HEADERS, ACCESS_CONTROL_ALLOW_METHODS, ACCESS_CONTROL_ALLOW_ORIGIN,
+    ACCESS_CONTROL_EXPOSE_HEADERS, ACCESS_CONTROL_MAX_AGE, ACCESS_CONTROL_REQUEST_HEADERS, ALLOW,
+    AUTHORIZATION, CONTENT_TYPE, HOST, ORIGIN,
+};
 use http_body_util::combinators::BoxBody;
-use http_body_util::{BodyExt, Full};
+use http_body_util::{BodyExt, Empty, Full};
 use http_utils::error::ApiError;
 use hyper::body::Incoming;
-use hyper::http::{HeaderName, HeaderValue};
+use hyper::http::response::Builder;
+use hyper::http::{HeaderMap, HeaderName, HeaderValue};
 use hyper::{Request, Response, StatusCode};
 use indexmap::IndexMap;
 use moka::sync::Cache;
@@ -67,6 +72,15 @@ use crate::util::deserialize_json_string;
 
 static EMPTY_JSON_SCHEMA: &str = r#"{"schemas":[]}"#;
 const INTROSPECTION_SQL: &str = POSTGRESQL_INTROSPECTION_SQL;
+const HEADER_VALUE_ALLOW_ALL_ORIGINS: HeaderValue = HeaderValue::from_static("*");
+// CORS headers values
+const ACCESS_CONTROL_ALLOW_METHODS_VALUE: HeaderValue =
+    HeaderValue::from_static("GET, POST, PATCH, PUT, DELETE, OPTIONS");
+const ACCESS_CONTROL_MAX_AGE_VALUE: HeaderValue = HeaderValue::from_static("86400");
+const ACCESS_CONTROL_EXPOSE_HEADERS_VALUE: HeaderValue = HeaderValue::from_static(
+    "Content-Encoding, Content-Location, Content-Range, Content-Type, Date, Location, Server, Transfer-Encoding, Range-Unit",
+);
+const ACCESS_CONTROL_ALLOW_HEADERS_VALUE: HeaderValue = HeaderValue::from_static("Authorization");
 
 // A wrapper around the DbSchema that allows for self-referencing
 #[self_referencing]
@@ -137,6 +151,8 @@ pub struct ApiConfig {
     pub role_claim_key: String,
     #[serde(default, deserialize_with = "deserialize_comma_separated_option")]
     pub db_extra_search_path: Option<Vec<String>>,
+    #[serde(default, deserialize_with = "deserialize_comma_separated_option")]
+    pub server_cors_allowed_origins: Option<Vec<String>>,
 }
 
 // The DbSchemaCache is a cache of the ApiConfig and DbSchemaOwned for each endpoint
@@ -165,7 +181,13 @@ impl DbSchemaCache {
         }
     }
 
-    pub async fn get_cached_or_remote(
+    pub fn get_cached(
+        &self,
+        endpoint_id: &EndpointCacheKey,
+    ) -> Option<Arc<(ApiConfig, DbSchemaOwned)>> {
+        count_cache_outcome(CacheKind::Schema, self.0.get(endpoint_id))
+    }
+    pub async fn get_remote(
         &self,
         endpoint_id: &EndpointCacheKey,
         auth_header: &HeaderValue,
@@ -174,47 +196,42 @@ impl DbSchemaCache {
         ctx: &RequestContext,
         config: &'static ProxyConfig,
     ) -> Result<Arc<(ApiConfig, DbSchemaOwned)>, RestError> {
-        let cache_result = count_cache_outcome(CacheKind::Schema, self.0.get(endpoint_id));
-        match cache_result {
-            Some(v) => Ok(v),
-            None => {
-                info!("db_schema cache miss for endpoint: {:?}", endpoint_id);
-                let remote_value = self
-                    .get_remote(auth_header, connection_string, client, ctx, config)
-                    .await;
-                let (api_config, schema_owned) = match remote_value {
-                    Ok((api_config, schema_owned)) => (api_config, schema_owned),
-                    Err(e @ RestError::SchemaTooLarge) => {
-                        // for the case where the schema is too large, we cache an empty dummy value
-                        // all the other requests will fail without triggering the introspection query
-                        let schema_owned = serde_json::from_str::<DbSchemaOwned>(EMPTY_JSON_SCHEMA)
-                            .map_err(|e| JsonDeserialize { source: e })?;
+        info!("db_schema cache miss for endpoint: {:?}", endpoint_id);
+        let remote_value = self
+            .internal_get_remote(auth_header, connection_string, client, ctx, config)
+            .await;
+        let (api_config, schema_owned) = match remote_value {
+            Ok((api_config, schema_owned)) => (api_config, schema_owned),
+            Err(e @ RestError::SchemaTooLarge) => {
+                // for the case where the schema is too large, we cache an empty dummy value
+                // all the other requests will fail without triggering the introspection query
+                let schema_owned = serde_json::from_str::<DbSchemaOwned>(EMPTY_JSON_SCHEMA)
+                    .map_err(|e| JsonDeserialize { source: e })?;
 
-                        let api_config = ApiConfig {
-                            db_schemas: vec![],
-                            db_anon_role: None,
-                            db_max_rows: None,
-                            db_allowed_select_functions: vec![],
-                            role_claim_key: String::new(),
-                            db_extra_search_path: None,
-                        };
-                        let value = Arc::new((api_config, schema_owned));
-                        count_cache_insert(CacheKind::Schema);
-                        self.0.insert(endpoint_id.clone(), value);
-                        return Err(e);
-                    }
-                    Err(e) => {
-                        return Err(e);
-                    }
+                let api_config = ApiConfig {
+                    db_schemas: vec![],
+                    db_anon_role: None,
+                    db_max_rows: None,
+                    db_allowed_select_functions: vec![],
+                    role_claim_key: String::new(),
+                    db_extra_search_path: None,
+                    server_cors_allowed_origins: None,
                 };
                 let value = Arc::new((api_config, schema_owned));
                 count_cache_insert(CacheKind::Schema);
-                self.0.insert(endpoint_id.clone(), value.clone());
-                Ok(value)
+                self.0.insert(endpoint_id.clone(), value);
+                return Err(e);
             }
-        }
+            Err(e) => {
+                return Err(e);
+            }
+        };
+        let value = Arc::new((api_config, schema_owned));
+        count_cache_insert(CacheKind::Schema);
+        self.0.insert(endpoint_id.clone(), value.clone());
+        Ok(value)
     }
-    pub async fn get_remote(
+    async fn internal_get_remote(
         &self,
         auth_header: &HeaderValue,
         connection_string: &str,
@@ -531,7 +548,7 @@ pub(crate) async fn handle(
 ) -> Result<Response<BoxBody<Bytes, hyper::Error>>, ApiError> {
     let result = handle_inner(cancel, config, &ctx, request, backend).await;
 
-    let mut response = match result {
+    let response = match result {
         Ok(r) => {
             ctx.set_success();
 
@@ -640,9 +657,6 @@ pub(crate) async fn handle(
         }
     };
 
-    response
-        .headers_mut()
-        .insert("Access-Control-Allow-Origin", HeaderValue::from_static("*"));
     Ok(response)
 }
 
@@ -722,6 +736,37 @@ async fn handle_inner(
     }
 }
 
+fn apply_common_cors_headers(
+    response: &mut Builder,
+    request_headers: &HeaderMap,
+    allowed_origins: Option<&Vec<String>>,
+) {
+    let request_origin = request_headers
+        .get(ORIGIN)
+        .map(|v| v.to_str().unwrap_or(""));
+
+    let response_allow_origin = match (request_origin, allowed_origins) {
+        (Some(or), Some(allowed_origins)) => {
+            if allowed_origins.iter().any(|o| o == or) {
+                Some(HeaderValue::from_str(or).unwrap_or(HEADER_VALUE_ALLOW_ALL_ORIGINS))
+            } else {
+                None
+            }
+        }
+        (Some(_), None) => Some(HEADER_VALUE_ALLOW_ALL_ORIGINS),
+        _ => None,
+    };
+    if let Some(h) = response.headers_mut() {
+        h.insert(
+            ACCESS_CONTROL_EXPOSE_HEADERS,
+            ACCESS_CONTROL_EXPOSE_HEADERS_VALUE,
+        );
+        if let Some(origin) = response_allow_origin {
+            h.insert(ACCESS_CONTROL_ALLOW_ORIGIN, origin);
+        }
+    }
+}
+
 #[allow(clippy::too_many_arguments)]
 async fn handle_rest_inner(
     config: &'static ProxyConfig,
@@ -733,12 +778,6 @@ async fn handle_rest_inner(
     jwt: String,
     backend: Arc<PoolingBackend>,
 ) -> Result<Response<BoxBody<Bytes, hyper::Error>>, RestError> {
-    // validate the jwt token
-    let jwt_parsed = backend
-        .authenticate_with_jwt(ctx, &conn_info.user_info, jwt)
-        .await
-        .map_err(HttpConnError::from)?;
-
     let db_schema_cache =
         config
             .rest_config
@@ -754,28 +793,83 @@ async fn handle_rest_inner(
             message: "Failed to get endpoint cache key".to_string(),
         }))?;
 
-    let mut client = backend.connect_to_local_proxy(ctx, conn_info).await?;
-
     let (parts, originial_body) = request.into_parts();
 
+    // try and get the cached entry for this endpoint
+    // it contains the api config and the introspected db schema
+    let cached_entry = db_schema_cache.get_cached(&endpoint_cache_key);
+
+    let allowed_origins = cached_entry
+        .as_ref()
+        .and_then(|arc| arc.0.server_cors_allowed_origins.as_ref());
+
+    let mut response = Response::builder();
+    apply_common_cors_headers(&mut response, &parts.headers, allowed_origins);
+
+    // handle the OPTIONS request
+    if parts.method == Method::OPTIONS {
+        let allowed_headers = parts
+            .headers
+            .get(ACCESS_CONTROL_REQUEST_HEADERS)
+            .and_then(|a| a.to_str().ok())
+            .filter(|v| !v.is_empty())
+            .map_or_else(
+                || "Authorization".to_string(),
+                |v| format!("{v}, Authorization"),
+            );
+        return response
+            .status(StatusCode::OK)
+            .header(
+                ACCESS_CONTROL_ALLOW_METHODS,
+                ACCESS_CONTROL_ALLOW_METHODS_VALUE,
+            )
+            .header(ACCESS_CONTROL_MAX_AGE, ACCESS_CONTROL_MAX_AGE_VALUE)
+            .header(
+                ACCESS_CONTROL_ALLOW_HEADERS,
+                HeaderValue::from_str(&allowed_headers)
+                    .unwrap_or(ACCESS_CONTROL_ALLOW_HEADERS_VALUE),
+            )
+            .header(ALLOW, ACCESS_CONTROL_ALLOW_METHODS_VALUE)
+            .body(Empty::new().map_err(|x| match x {}).boxed())
+            .map_err(|e| {
+                RestError::SubzeroCore(InternalError {
+                    message: e.to_string(),
+                })
+            });
+    }
+
+    // validate the jwt token
+    let jwt_parsed = backend
+        .authenticate_with_jwt(ctx, &conn_info.user_info, jwt)
+        .await
+        .map_err(HttpConnError::from)?;
+
     let auth_header = parts
         .headers
         .get(AUTHORIZATION)
         .ok_or(RestError::SubzeroCore(InternalError {
             message: "Authorization header is required".to_string(),
         }))?;
+    let mut client = backend.connect_to_local_proxy(ctx, conn_info).await?;
 
-    let entry = db_schema_cache
-        .get_cached_or_remote(
-            &endpoint_cache_key,
-            auth_header,
-            connection_string,
-            &mut client,
-            ctx,
-            config,
-        )
-        .await?;
+    let entry = match cached_entry {
+        Some(e) => e,
+        None => {
+            // if not cached, get the remote entry (will run the introspection query)
+            db_schema_cache
+                .get_remote(
+                    &endpoint_cache_key,
+                    auth_header,
+                    connection_string,
+                    &mut client,
+                    ctx,
+                    config,
+                )
+                .await?
+        }
+    };
     let (api_config, db_schema_owned) = entry.as_ref();
+
     let db_schema = db_schema_owned.borrow_schema();
 
     let db_schemas = &api_config.db_schemas; // list of schemas available for the api
@@ -999,8 +1093,8 @@ async fn handle_rest_inner(
     let _metrics = client.metrics(ctx); // FIXME: is everything in the context set correctly?
 
     // send the request to the local proxy
-    let response = make_raw_local_proxy_request(&mut client, headers, req_body).await?;
-    let (parts, body) = response.into_parts();
+    let proxy_response = make_raw_local_proxy_request(&mut client, headers, req_body).await?;
+    let (response_parts, body) = proxy_response.into_parts();
 
     let max_response = config.http_config.max_response_size_bytes;
     let bytes = read_body_with_limit(body, max_response)
@@ -1009,7 +1103,7 @@ async fn handle_rest_inner(
 
     // if the response status is greater than 399, then it is an error
     // FIXME: check if there are other error codes or shapes of the response
-    if parts.status.as_u16() > 399 {
+    if response_parts.status.as_u16() > 399 {
         // turn this postgres error from the json into PostgresError
         let postgres_error = serde_json::from_slice(&bytes)
             .map_err(|e| RestError::SubzeroCore(JsonDeserialize { source: e }))?;
@@ -1175,7 +1269,7 @@ async fn handle_rest_inner(
         .boxed();
 
     // build the response
-    let mut response = Response::builder()
+    response = response
         .status(StatusCode::from_u16(status).unwrap_or(StatusCode::INTERNAL_SERVER_ERROR))
         .header(CONTENT_TYPE, http_content_type);
 

storage_controller/src/compute_hook.rs

@@ -510,7 +510,6 @@ impl ApiMethod for ComputeHookTenant {
                 tracing::info!("Reconfiguring pageservers for endpoint {endpoint_name}");
 
                 let shard_count = match shards.len() {
-                    0 => panic!("no shards"),
                     1 => ShardCount::unsharded(),
                     n => ShardCount(n.try_into().expect("too many shards")),
                 };

storage_controller/src/http.rs

@@ -644,6 +644,7 @@ async fn handle_tenant_timeline_safekeeper_migrate(
     req: Request<Body>,
 ) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&req, "tenant_id")?;
+    // TODO(diko): it's not PS operation, there should be a different permission scope.
     check_permissions(&req, Scope::PageServerApi)?;
     maybe_rate_limit(&req, tenant_id).await;
 
@@ -665,6 +666,23 @@ async fn handle_tenant_timeline_safekeeper_migrate(
     json_response(StatusCode::OK, ())
 }
 
+async fn handle_tenant_timeline_safekeeper_migrate_abort(
+    service: Arc<Service>,
+    req: Request<Body>,
+) -> Result<Response<Body>, ApiError> {
+    let tenant_id: TenantId = parse_request_param(&req, "tenant_id")?;
+    let timeline_id: TimelineId = parse_request_param(&req, "timeline_id")?;
+    // TODO(diko): it's not PS operation, there should be a different permission scope.
+    check_permissions(&req, Scope::PageServerApi)?;
+    maybe_rate_limit(&req, tenant_id).await;
+
+    service
+        .tenant_timeline_safekeeper_migrate_abort(tenant_id, timeline_id)
+        .await?;
+
+    json_response(StatusCode::OK, ())
+}
+
 async fn handle_tenant_timeline_lsn_lease(
     service: Arc<Service>,
     req: Request<Body>,
@@ -2611,6 +2629,16 @@ pub fn make_router(
                 )
             },
         )
+        .post(
+            "/v1/tenant/:tenant_id/timeline/:timeline_id/safekeeper_migrate_abort",
+            |r| {
+                tenant_service_handler(
+                    r,
+                    handle_tenant_timeline_safekeeper_migrate_abort,
+                    RequestName("v1_tenant_timeline_safekeeper_migrate_abort"),
+                )
+            },
+        )
         // LSN lease passthrough to all shards
         .post(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/lsn_lease",

storage_controller/src/service/safekeeper_service.rs

@@ -1230,10 +1230,7 @@ impl Service {
             }
             // It it is the same new_sk_set, we can continue the migration (retry).
         } else {
-            let prev_finished = timeline.cplane_notified_generation == timeline.generation
-                && timeline.sk_set_notified_generation == timeline.generation;
-
-            if !prev_finished {
+            if !is_migration_finished(&timeline) {
                 // The previous migration is committed, but the finish step failed.
                 // Safekeepers/cplane might not know about the last membership configuration.
                 // Retry the finish step to ensure smooth migration.
@@ -1545,6 +1542,8 @@ impl Service {
         timeline_id: TimelineId,
         timeline: &TimelinePersistence,
     ) -> Result<(), ApiError> {
+        tracing::info!(generation=?timeline.generation, sk_set=?timeline.sk_set, new_sk_set=?timeline.new_sk_set, "retrying finish safekeeper migration");
+
         if timeline.new_sk_set.is_some() {
             // Logical error, should never happen.
             return Err(ApiError::InternalServerError(anyhow::anyhow!(
@@ -1624,4 +1623,120 @@ impl Service {
 
         Ok(wal_positions[quorum_size - 1])
     }
+
+    /// Abort ongoing safekeeper migration.
+    pub(crate) async fn tenant_timeline_safekeeper_migrate_abort(
+        self: &Arc<Self>,
+        tenant_id: TenantId,
+        timeline_id: TimelineId,
+    ) -> Result<(), ApiError> {
+        // TODO(diko): per-tenant lock is too wide. Consider introducing per-timeline locks.
+        let _tenant_lock = trace_shared_lock(
+            &self.tenant_op_locks,
+            tenant_id,
+            TenantOperations::TimelineSafekeeperMigrate,
+        )
+        .await;
+
+        // Fetch current timeline configuration from the configuration storage.
+        let timeline = self
+            .persistence
+            .get_timeline(tenant_id, timeline_id)
+            .await?;
+
+        let Some(timeline) = timeline else {
+            return Err(ApiError::NotFound(
+                anyhow::anyhow!(
+                    "timeline {tenant_id}/{timeline_id} doesn't exist in timelines table"
+                )
+                .into(),
+            ));
+        };
+
+        let mut generation = SafekeeperGeneration::new(timeline.generation as u32);
+
+        let Some(new_sk_set) = &timeline.new_sk_set else {
+            // No new_sk_set -> no active migration that we can abort.
+            tracing::info!("timeline has no active migration");
+
+            if !is_migration_finished(&timeline) {
+                // The last migration is committed, but the finish step failed.
+                // Safekeepers/cplane might not know about the last membership configuration.
+                // Retry the finish step to make the timeline state clean.
+                self.finish_safekeeper_migration_retry(tenant_id, timeline_id, &timeline)
+                    .await?;
+            }
+            return Ok(());
+        };
+
+        tracing::info!(sk_set=?timeline.sk_set, ?new_sk_set, ?generation, "aborting timeline migration");
+
+        let cur_safekeepers = self.get_safekeepers(&timeline.sk_set)?;
+        let new_safekeepers = self.get_safekeepers(new_sk_set)?;
+
+        let cur_sk_member_set =
+            Self::make_member_set(&cur_safekeepers).map_err(ApiError::InternalServerError)?;
+
+        // Increment current generation and remove new_sk_set from the timeline to abort the migration.
+        generation = generation.next();
+
+        let mconf = membership::Configuration {
+            generation,
+            members: cur_sk_member_set,
+            new_members: None,
+        };
+
+        // Exclude safekeepers which were added during the current migration.
+        let cur_ids: HashSet<NodeId> = cur_safekeepers.iter().map(|sk| sk.get_id()).collect();
+        let exclude_safekeepers = new_safekeepers
+            .into_iter()
+            .filter(|sk| !cur_ids.contains(&sk.get_id()))
+            .collect::<Vec<_>>();
+
+        let exclude_requests = exclude_safekeepers
+            .iter()
+            .map(|sk| TimelinePendingOpPersistence {
+                sk_id: sk.skp.id,
+                tenant_id: tenant_id.to_string(),
+                timeline_id: timeline_id.to_string(),
+                generation: generation.into_inner() as i32,
+                op_kind: SafekeeperTimelineOpKind::Exclude,
+            })
+            .collect::<Vec<_>>();
+
+        let cur_sk_set = cur_safekeepers
+            .iter()
+            .map(|sk| sk.get_id())
+            .collect::<Vec<_>>();
+
+        // Persist new mconf and exclude requests.
+        self.persistence
+            .update_timeline_membership(
+                tenant_id,
+                timeline_id,
+                generation,
+                &cur_sk_set,
+                None,
+                &exclude_requests,
+            )
+            .await?;
+
+        // At this point we have already commited the abort, but still need to notify
+        // cplane/safekeepers with the new mconf. That's what finish_safekeeper_migration does.
+        self.finish_safekeeper_migration(
+            tenant_id,
+            timeline_id,
+            &cur_safekeepers,
+            &mconf,
+            &exclude_safekeepers,
+        )
+        .await?;
+
+        Ok(())
+    }
+}
+
+fn is_migration_finished(timeline: &TimelinePersistence) -> bool {
+    timeline.cplane_notified_generation == timeline.generation
+        && timeline.sk_set_notified_generation == timeline.generation
 }

test_runner/fixtures/neon_cli.py

@@ -530,10 +530,7 @@ class NeonLocalCli(AbstractNeonCli):
             args.extend(["--external-http-port", str(external_http_port)])
         if internal_http_port is not None:
             args.extend(["--internal-http-port", str(internal_http_port)])
-
-        # XXX: By checking for None, we enable the new communicator for all tests
-        # by default
-        if grpc or grpc is None:
+        if grpc:
             args.append("--grpc")
         if endpoint_id is not None:
             args.append(endpoint_id)

test_runner/fixtures/neon_fixtures.py

@@ -2323,6 +2323,19 @@ class NeonStorageController(MetricsGetter, LogUtils):
         response.raise_for_status()
         log.info(f"migrate_safekeepers success: {response.json()}")
 
+    def abort_safekeeper_migration(
+        self,
+        tenant_id: TenantId,
+        timeline_id: TimelineId,
+    ):
+        response = self.request(
+            "POST",
+            f"{self.api}/v1/tenant/{tenant_id}/timeline/{timeline_id}/safekeeper_migrate_abort",
+            headers=self.headers(TokenScope.PAGE_SERVER_API),
+        )
+        response.raise_for_status()
+        log.info(f"abort_safekeeper_migration success: {response.json()}")
+
     def locate(self, tenant_id: TenantId) -> list[dict[str, Any]]:
         """
         :return: list of {"shard_id": "", "node_id": int, "listen_pg_addr": str, "listen_pg_port": int, "listen_http_addr": str, "listen_http_port": int}
@@ -4778,7 +4791,7 @@ class Endpoint(PgProtocol, LogUtils):
 
         # set small 'max_replication_write_lag' to enable backpressure
         # and make tests more stable.
-        config_lines += ["max_replication_write_lag=15MB"]
+        config_lines = ["max_replication_write_lag=15MB"] + config_lines
 
         # Delete file cache if it exists (and we're recreating the endpoint)
         if USE_LFC:

test_runner/fixtures/pageserver/allowed_errors.py

@@ -90,8 +90,6 @@ DEFAULT_PAGESERVER_ALLOWED_ERRORS = (
     # During shutdown, DownloadError::Cancelled may be logged as an error.  Cleaning this
     # up is tracked in https://github.com/neondatabase/neon/issues/6096
     ".*Cancelled, shutting down.*",
-    # gRPC request failures during shutdown.
-    ".*grpc:pageservice.*request failed with Unavailable: timeline is shutting down.*",
     # Open layers are only rolled at Lsn boundaries to avoid name clashses.
     # Hence, we can overshoot the soft limit set by checkpoint distance.
     # This is especially pronounced in tests that set small checkpoint

test_runner/regress/test_branching.py

@@ -157,7 +157,6 @@ def test_cannot_create_endpoint_on_non_uploaded_timeline(neon_env_builder: NeonE
         [
             ".*request{method=POST path=/v1/tenant/.*/timeline request_id=.*}: request was dropped before completing.*",
             ".*page_service_conn_main.*: query handler for 'basebackup .* ERROR: Not found: Timeline",
-            ".*request failed with Unavailable: Timeline .* is not active",
         ]
     )
     ps_http = env.pageserver.http_client()
@@ -195,10 +194,7 @@ def test_cannot_create_endpoint_on_non_uploaded_timeline(neon_env_builder: NeonE
 
         env.neon_cli.mappings_map_branch(initial_branch, env.initial_tenant, env.initial_timeline)
 
-        with pytest.raises(
-            RuntimeError,
-            match=f"Timeline {env.initial_tenant}/{env.initial_timeline} is not active",
-        ):
+        with pytest.raises(RuntimeError, match="ERROR: Not found: Timeline"):
             env.endpoints.create_start(
                 initial_branch, tenant_id=env.initial_tenant, basebackup_request_tries=2
             )

test_runner/regress/test_lfc_prewarm.py

@@ -101,37 +101,20 @@ def check_prewarmed_contains(
 
 
 @pytest.mark.skipif(not USE_LFC, reason="LFC is disabled, skipping")
-@pytest.mark.parametrize("grpc", [True, False])
 @pytest.mark.parametrize("method", METHOD_VALUES, ids=METHOD_IDS)
-def test_lfc_prewarm(neon_simple_env: NeonEnv, method: PrewarmMethod, grpc: bool):
+def test_lfc_prewarm(neon_simple_env: NeonEnv, method: PrewarmMethod):
     """
     Test we can offload endpoint's LFC cache to endpoint storage.
     Test we can prewarm endpoint with LFC cache loaded from endpoint storage.
     """
     env = neon_simple_env
     n_records = 1000000
-
-    # The `neon.file_cache_prewarm_limit` GUC sets the max number of *chunks* to
-    # load. So the number of *pages* loaded depends on the chunk size. With the
-    # new communicator, the new LFC implementation doesn't do chunking so the
-    # limit is the number of pages, while with the old implementation, the
-    # default chunk size 1 MB chunks.
-    #
-    # Therefore with the old implementation, 1000 chunks equals 128000 pages, if
-    # all the chunks are fully dense. In practice they are sparse, but should
-    # amount to > 10000 pages anyway. (We have an assertion below that at least
-    # 10000 LFC pages are in use after prewarming)
-    if grpc:
-        prewarm_limit = 15000
-    else:
-        prewarm_limit = 1000
-
     cfg = [
         "autovacuum = off",
         "shared_buffers=1MB",
         "neon.max_file_cache_size=1GB",
         "neon.file_cache_size_limit=1GB",
-        f"neon.file_cache_prewarm_limit={prewarm_limit}",
+        "neon.file_cache_prewarm_limit=1000",
     ]
 
     if method == PrewarmMethod.AUTOPREWARM:
@@ -140,10 +123,9 @@ def test_lfc_prewarm(neon_simple_env: NeonEnv, method: PrewarmMethod, grpc: bool
             config_lines=cfg,
             autoprewarm=True,
             offload_lfc_interval_seconds=AUTOOFFLOAD_INTERVAL_SECS,
-            grpc=grpc,
         )
     else:
-        endpoint = env.endpoints.create_start(branch_name="main", config_lines=cfg, grpc=grpc)
+        endpoint = env.endpoints.create_start(branch_name="main", config_lines=cfg)
 
     pg_conn = endpoint.connect()
     pg_cur = pg_conn.cursor()
@@ -180,7 +162,7 @@ def test_lfc_prewarm(neon_simple_env: NeonEnv, method: PrewarmMethod, grpc: bool
     log.info(f"Used LFC size: {lfc_used_pages}")
     pg_cur.execute("select * from neon.get_prewarm_info()")
     total, prewarmed, skipped, _ = pg_cur.fetchall()[0]
-    assert lfc_used_pages >= 10000
+    assert lfc_used_pages > 10000
     assert total > 0
     assert prewarmed > 0
     assert total == prewarmed + skipped
@@ -204,7 +186,7 @@ def test_lfc_prewarm_cancel(neon_simple_env: NeonEnv):
         "shared_buffers=1MB",
         "neon.max_file_cache_size=1GB",
         "neon.file_cache_size_limit=1GB",
-        "neon.file_cache_prewarm_limit=2000000",
+        "neon.file_cache_prewarm_limit=1000",
     ]
     endpoint = env.endpoints.create_start(branch_name="main", config_lines=cfg)
 

test_runner/regress/test_lfc_resize.py

@@ -35,23 +35,8 @@ def test_lfc_resize(neon_simple_env: NeonEnv, pg_bin: PgBin):
     n_resize = 10
     scale = 20
 
-    def get_lfc_size() -> tuple[int, int]:
-        lfc_file_path = endpoint.lfc_path()
-        lfc_file_size = lfc_file_path.stat().st_size
-        res = subprocess.run(
-            ["ls", "-sk", lfc_file_path], check=True, text=True, capture_output=True
-        )
-        lfc_file_blocks = re.findall("([0-9A-F]+)", res.stdout)[0]
-        log.info(f"Size of LFC file {lfc_file_size / (1024 * 1024)}MB, alloc'd KB {lfc_file_blocks}, blocks {int(lfc_file_blocks)/8}")
-
-        return (lfc_file_size, lfc_file_blocks)
-
-    log.info("Original LFC size")
-    get_lfc_size()
-    
     def run_pgbench(connstr: str):
         log.info(f"Start a pgbench workload on pg {connstr}")
-        get_lfc_size()
         pg_bin.run_capture(["pgbench", "-i", f"-s{scale}", connstr])
         pg_bin.run_capture(["pgbench", "-c10", f"-T{n_resize}", "-Mprepared", "-S", connstr])
 
@@ -65,7 +50,18 @@ def test_lfc_resize(neon_simple_env: NeonEnv, pg_bin: PgBin):
     cur = conn.cursor()
 
     cur.execute("create extension neon")
-    
+
+    def get_lfc_size() -> tuple[int, int]:
+        lfc_file_path = endpoint.lfc_path()
+        lfc_file_size = lfc_file_path.stat().st_size
+        res = subprocess.run(
+            ["ls", "-sk", lfc_file_path], check=True, text=True, capture_output=True
+        )
+        lfc_file_blocks = re.findall("([0-9A-F]+)", res.stdout)[0]
+        log.info(f"Size of LFC file {lfc_file_size}, blocks {lfc_file_blocks}")
+
+        return (lfc_file_size, lfc_file_blocks)
+
     # For as long as pgbench is running, twiddle the LFC size once a second.
     # Note that we launch this immediately, already while the "pgbench -i"
     # initialization step is still running. That's quite a different workload
@@ -76,14 +72,11 @@ def test_lfc_resize(neon_simple_env: NeonEnv, pg_bin: PgBin):
         # is really doing something.
         size = random.randint(192, 512)
         cur.execute(f"alter system set neon.file_cache_size_limit='{size}MB'")
-        log.info(f"alter system set neon.file_cache_size_limit='{size}MB'")
         cur.execute("select pg_reload_conf()")
         time.sleep(1)
-        get_lfc_size()
 
     thread.join()
 
-    log.info("Running seqscan.")
     # Fill LFC: seqscan should fetch the whole table in cache.
     # It is needed for further correct evaluation of LFC file size
     # (a sparse chunk of LFC takes less than 1 MB on disk).
@@ -93,13 +86,6 @@ def test_lfc_resize(neon_simple_env: NeonEnv, pg_bin: PgBin):
     (lfc_file_size, lfc_file_blocks) = get_lfc_size()
     assert int(lfc_file_blocks) > 128 * 1024
 
-    time.sleep(2)
-    cur.execute("select count(*) from local_cache")
-    log.info(f"local_cache size: {cur.fetchall()[0][0]}")
-
-    
-    log.info("Beginning actual shrink.")
-    
     # At the end, set it at 100 MB, and perform a final check that the disk usage
     # of the file is in that ballbark.
     #
@@ -138,4 +124,4 @@ def test_lfc_resize(neon_simple_env: NeonEnv, pg_bin: PgBin):
         nretries = nretries - 1
         time.sleep(1)
 
-    # assert local_cache_size == used_pages
+    assert local_cache_size == used_pages

test_runner/regress/test_normal_work.py

@@ -17,9 +17,7 @@ def check_tenant(
     config_lines = [
         f"neon.safekeeper_proto_version = {safekeeper_proto_version}",
     ]
-    endpoint = env.endpoints.create_start(
-        "main", tenant_id=tenant_id, config_lines=config_lines, grpc=True
-    )
+    endpoint = env.endpoints.create_start("main", tenant_id=tenant_id, config_lines=config_lines)
     # we rely upon autocommit after each statement
     res_1 = endpoint.safe_psql_many(
         queries=[

test_runner/regress/test_replica_promotes.py

@@ -145,6 +145,7 @@ def test_replica_promote(neon_simple_env: NeonEnv, method: PromoteMethod):
         stop_and_check_lsn(secondary, None)
 
     if method == PromoteMethod.COMPUTE_CTL:
+        log.info("Restarting primary to check new config")
         secondary.stop()
         # In production, compute ultimately receives new compute spec from cplane.
         secondary.respec(mode="Primary")

test_runner/regress/test_safekeeper_migration.py

@@ -460,3 +460,91 @@ def test_pull_from_most_advanced_sk(neon_env_builder: NeonEnvBuilder):
 
     ep.start(safekeeper_generation=5, safekeepers=new_sk_set2)
     assert ep.safe_psql("SELECT * FROM t") == [(0,), (1,)]
+
+
+def test_abort_safekeeper_migration(neon_env_builder: NeonEnvBuilder):
+    """
+    Test that safekeeper migration can be aborted.
+    1. Insert failpoints and ensure the abort successfully reverts the timeline state.
+    2. Check that endpoint is operational after the abort.
+    """
+    neon_env_builder.num_safekeepers = 2
+    neon_env_builder.storage_controller_config = {
+        "timelines_onto_safekeepers": True,
+        "timeline_safekeeper_count": 1,
+    }
+    env = neon_env_builder.init_start()
+    env.pageserver.allowed_errors.extend(PAGESERVER_ALLOWED_ERRORS)
+
+    mconf = env.storage_controller.timeline_locate(env.initial_tenant, env.initial_timeline)
+    assert len(mconf["sk_set"]) == 1
+    cur_sk = mconf["sk_set"][0]
+    cur_gen = 1
+
+    ep = env.endpoints.create("main", tenant_id=env.initial_tenant)
+    ep.start(safekeeper_generation=1, safekeepers=mconf["sk_set"])
+    ep.safe_psql("CREATE EXTENSION neon_test_utils;")
+    ep.safe_psql("CREATE TABLE t(a int)")
+    ep.safe_psql("INSERT INTO t VALUES (1)")
+
+    another_sk = [sk.id for sk in env.safekeepers if sk.id != cur_sk][0]
+
+    failpoints = [
+        "sk-migration-after-step-3",
+        "sk-migration-after-step-4",
+        "sk-migration-after-step-5",
+        "sk-migration-after-step-7",
+    ]
+
+    for fp in failpoints:
+        env.storage_controller.configure_failpoints((fp, "return(1)"))
+
+        with pytest.raises(StorageControllerApiException, match=f"failpoint {fp}"):
+            env.storage_controller.migrate_safekeepers(
+                env.initial_tenant, env.initial_timeline, [another_sk]
+            )
+        cur_gen += 1
+
+        env.storage_controller.configure_failpoints((fp, "off"))
+
+        # We should have a joint mconf after the failure.
+        mconf = env.storage_controller.timeline_locate(env.initial_tenant, env.initial_timeline)
+        assert mconf["generation"] == cur_gen
+        assert mconf["sk_set"] == [cur_sk]
+        assert mconf["new_sk_set"] == [another_sk]
+
+        env.storage_controller.abort_safekeeper_migration(env.initial_tenant, env.initial_timeline)
+        cur_gen += 1
+
+        # Abort should revert the timeline to the previous sk_set and increment the generation.
+        mconf = env.storage_controller.timeline_locate(env.initial_tenant, env.initial_timeline)
+        assert mconf["generation"] == cur_gen
+        assert mconf["sk_set"] == [cur_sk]
+        assert mconf["new_sk_set"] is None
+
+        assert ep.safe_psql("SHOW neon.safekeepers")[0][0].startswith(f"g#{cur_gen}:")
+        ep.safe_psql(f"INSERT INTO t VALUES ({cur_gen})")
+
+    # After step-8 the final mconf is committed and the migration is not abortable anymore.
+    # So the abort should not abort anything.
+    env.storage_controller.configure_failpoints(("sk-migration-after-step-8", "return(1)"))
+
+    with pytest.raises(StorageControllerApiException, match="failpoint sk-migration-after-step-8"):
+        env.storage_controller.migrate_safekeepers(
+            env.initial_tenant, env.initial_timeline, [another_sk]
+        )
+    cur_gen += 2
+
+    env.storage_controller.configure_failpoints((fp, "off"))
+
+    env.storage_controller.abort_safekeeper_migration(env.initial_tenant, env.initial_timeline)
+
+    # The migration is fully committed, no abort should have been performed.
+    mconf = env.storage_controller.timeline_locate(env.initial_tenant, env.initial_timeline)
+    assert mconf["generation"] == cur_gen
+    assert mconf["sk_set"] == [another_sk]
+    assert mconf["new_sk_set"] is None
+
+    ep.safe_psql(f"INSERT INTO t VALUES ({cur_gen})")
+    ep.clear_buffers()
+    assert ep.safe_psql("SELECT * FROM t") == [(i + 1,) for i in range(cur_gen) if i % 2 == 0]

workspace_hack/Cargo.toml

@@ -28,8 +28,8 @@ chrono = { version = "0.4", default-features = false, features = ["clock", "serd
 clap = { version = "4", features = ["derive", "env", "string"] }
 clap_builder = { version = "4", default-features = false, features = ["color", "env", "help", "std", "string", "suggestions", "usage"] }
 const-oid = { version = "0.9", default-features = false, features = ["db", "std"] }
-criterion = { version = "0.5", features = ["html_reports"] }
 crossbeam-epoch = { version = "0.9" }
+crossbeam-utils = { version = "0.8" }
 crypto-bigint = { version = "0.5", features = ["generic-array", "zeroize"] }
 der = { version = "0.7", default-features = false, features = ["derive", "flagset", "oid", "pem", "std"] }
 deranged = { version = "0.3", default-features = false, features = ["powerfmt", "serde", "std"] }
@@ -72,6 +72,7 @@ num-integer = { version = "0.1", features = ["i128"] }
 num-iter = { version = "0.1", default-features = false, features = ["i128", "std"] }
 num-rational = { version = "0.4", default-features = false, features = ["num-bigint-std", "std"] }
 num-traits = { version = "0.2", features = ["i128", "libm"] }
+once_cell = { version = "1" }
 p256 = { version = "0.13", features = ["jwk"] }
 parquet = { version = "53", default-features = false, features = ["zstd"] }
 portable-atomic = { version = "1", features = ["require-cas"] }
@@ -104,7 +105,7 @@ tokio-rustls = { version = "0.26", default-features = false, features = ["loggin
 tokio-stream = { version = "0.1", features = ["net", "sync"] }
 tokio-util = { version = "0.7", features = ["codec", "compat", "io-util", "rt"] }
 toml_edit = { version = "0.22", features = ["serde"] }
-tonic = { version = "0.13", default-features = false, features = ["codegen", "gzip", "prost", "router", "tls-native-roots", "tls-ring", "transport", "zstd"] }
+tonic = { version = "0.13", default-features = false, features = ["codegen", "gzip", "prost", "router", "server", "tls-native-roots", "tls-ring", "zstd"] }
 tower = { version = "0.5", default-features = false, features = ["balance", "buffer", "limit", "log"] }
 tracing = { version = "0.1", features = ["log"] }
 tracing-core = { version = "0.1" }
@@ -142,6 +143,7 @@ num-integer = { version = "0.1", features = ["i128"] }
 num-iter = { version = "0.1", default-features = false, features = ["i128", "std"] }
 num-rational = { version = "0.4", default-features = false, features = ["num-bigint-std", "std"] }
 num-traits = { version = "0.2", features = ["i128", "libm"] }
+once_cell = { version = "1" }
 parquet = { version = "53", default-features = false, features = ["zstd"] }
 prettyplease = { version = "0.2", default-features = false, features = ["verbatim"] }
 proc-macro2 = { version = "1" }