diff --git a/Dockerfile.compute-node b/Dockerfile.compute-node
index de8a904c02..f8429e72b8 100644
--- a/Dockerfile.compute-node
+++ b/Dockerfile.compute-node
@@ -517,6 +517,22 @@ RUN wget https://github.com/kelvich/pg_tiktoken/archive/801f84f08c6881c8aa30f405
     cargo pgx install --release && \
     echo "trusted = true" >> /usr/local/pgsql/share/extension/pg_tiktoken.control
 
+#########################################################################################
+#
+# Layer "pg-pgx-ulid-build"
+# Compile "pgx_ulid" extension
+#
+#########################################################################################
+
+FROM rust-extensions-build AS pg-pgx-ulid-build
+
+RUN wget https://github.com/pksunkara/pgx_ulid/archive/refs/tags/v0.1.0.tar.gz -O pgx_ulid.tar.gz && \
+    echo "908b7358e6f846e87db508ae5349fb56a88ee6305519074b12f3d5b0ff09f791 pgx_ulid.tar.gz" | sha256sum --check && \
+    mkdir pgx_ulid-src && cd pgx_ulid-src && tar xvzf ../pgx_ulid.tar.gz --strip-components=1 -C . && \
+    sed -i 's/pgx        = "=0.7.3"/pgx = { version = "0.7.3", features = [ "unsafe-postgres" ] }/g' Cargo.toml && \
+    cargo pgx install --release && \
+    echo "trusted = true" >> /usr/local/pgsql/share/extension/pgx_ulid.control
+
 #########################################################################################
 #
 # Layer "neon-pg-ext-build"
@@ -547,6 +563,7 @@ COPY --from=timescaledb-pg-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=pg-hint-plan-pg-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=kq-imcx-pg-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=pg-cron-pg-build /usr/local/pgsql/ /usr/local/pgsql/
+COPY --from=pg-pgx-ulid-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY pgxn/ pgxn/
 
 RUN make -j $(getconf _NPROCESSORS_ONLN) \
@@ -556,6 +573,10 @@ RUN make -j $(getconf _NPROCESSORS_ONLN) \
     make -j $(getconf _NPROCESSORS_ONLN) \
         PG_CONFIG=/usr/local/pgsql/bin/pg_config \
         -C pgxn/neon_utils \
+        -s install && \
+    make -j $(getconf _NPROCESSORS_ONLN) \
+        PG_CONFIG=/usr/local/pgsql/bin/pg_config \
+        -C pgxn/hnsw \
         -s install
 
 #########################################################################################
diff --git a/Makefile b/Makefile
index 9d78c5d0fc..ae979b8b4c 100644
--- a/Makefile
+++ b/Makefile
@@ -138,6 +138,11 @@ neon-pg-ext-%: postgres-%
 	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/$*/bin/pg_config CFLAGS='$(PG_CFLAGS) $(COPT)' \
 		-C $(POSTGRES_INSTALL_DIR)/build/neon-utils-$* \
 		-f $(ROOT_PROJECT_DIR)/pgxn/neon_utils/Makefile install
+	+@echo "Compiling hnsw $*"
+	mkdir -p $(POSTGRES_INSTALL_DIR)/build/hnsw-$*
+	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/$*/bin/pg_config CFLAGS='$(PG_CFLAGS) $(COPT)' \
+		-C $(POSTGRES_INSTALL_DIR)/build/hnsw-$* \
+		-f $(ROOT_PROJECT_DIR)/pgxn/hnsw/Makefile install
 
 .PHONY: neon-pg-ext-clean-%
 neon-pg-ext-clean-%:
@@ -153,6 +158,9 @@ neon-pg-ext-clean-%:
 	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/$*/bin/pg_config \
 	-C $(POSTGRES_INSTALL_DIR)/build/neon-utils-$* \
 	-f $(ROOT_PROJECT_DIR)/pgxn/neon_utils/Makefile clean
+	$(MAKE) PG_CONFIG=$(POSTGRES_INSTALL_DIR)/$*/bin/pg_config \
+	-C $(POSTGRES_INSTALL_DIR)/build/hnsw-$* \
+	-f $(ROOT_PROJECT_DIR)/pgxn/hnsw/Makefile clean
 
 .PHONY: neon-pg-ext
 neon-pg-ext: \
diff --git a/README.md b/README.md
index 8e6f2cda81..efa714e5be 100644
--- a/README.md
+++ b/README.md
@@ -28,18 +28,19 @@ See developer documentation in [SUMMARY.md](/docs/SUMMARY.md) for more informati
 * On Ubuntu or Debian, this set of packages should be sufficient to build the code:
 ```bash
 apt install build-essential libtool libreadline-dev zlib1g-dev flex bison libseccomp-dev \
-libssl-dev clang pkg-config libpq-dev cmake postgresql-client protobuf-compiler
+libssl-dev clang pkg-config libpq-dev cmake postgresql-client protobuf-compiler \
+libcurl4-openssl-dev
 ```
 * On Fedora, these packages are needed:
 ```bash
 dnf install flex bison readline-devel zlib-devel openssl-devel \
   libseccomp-devel perl clang cmake postgresql postgresql-contrib protobuf-compiler \
-  protobuf-devel
+  protobuf-devel libcurl-devel
 ```
 * On Arch based systems, these packages are needed:
 ```bash
 pacman -S base-devel readline zlib libseccomp openssl clang \
-postgresql-libs cmake postgresql protobuf
+postgresql-libs cmake postgresql protobuf curl
 ```
 
 Building Neon requires 3.15+ version of `protoc` (protobuf-compiler). If your distribution provides an older version, you can install a newer version from [here](https://github.com/protocolbuffers/protobuf/releases).
diff --git a/compute_tools/src/logger.rs b/compute_tools/src/logger.rs
index 1b5cf647b0..f6fc882968 100644
--- a/compute_tools/src/logger.rs
+++ b/compute_tools/src/logger.rs
@@ -33,5 +33,7 @@ pub fn init_tracing_and_logging(default_log_level: &str) -> anyhow::Result<()> {
         .init();
     tracing::info!("logging and tracing started");
 
+    utils::logging::replace_panic_hook_with_tracing_panic_hook().forget();
+
     Ok(())
 }
diff --git a/docs/pageserver-thread-mgmt.md b/docs/pageserver-thread-mgmt.md
index 0cc897f154..b911933528 100644
--- a/docs/pageserver-thread-mgmt.md
+++ b/docs/pageserver-thread-mgmt.md
@@ -52,9 +52,7 @@ completion, or shield the rest of the code from surprise cancellations
 by spawning a separate task. The code that handles incoming HTTP
 requests, for example, spawns a separate task for each request,
 because Hyper will drop the request-handling Future if the HTTP
-connection is lost.  (FIXME: our HTTP handlers do not do that
-currently, but we should fix that. See [issue
-3478](https://github.com/neondatabase/neon/issues/3478)).
+connection is lost.
 
 
 #### How to cancel, then?
diff --git a/libs/utils/src/http/endpoint.rs b/libs/utils/src/http/endpoint.rs
index db3642b507..7cb96d9094 100644
--- a/libs/utils/src/http/endpoint.rs
+++ b/libs/utils/src/http/endpoint.rs
@@ -40,6 +40,12 @@ struct RequestId(String);
 ///
 /// This also handles errors, logging them and converting them to an HTTP error response.
 ///
+/// NB: If the client disconnects, Hyper will drop the Future, without polling it to
+/// completion. In other words, the handler must be async cancellation safe! request_span
+/// prints a warning to the log when that happens, so that you have some trace of it in
+/// the log.
+///
+///
 /// There could be other ways to implement similar functionality:
 ///
 /// * procmacros placed on top of all handler methods
diff --git a/pageserver/src/bin/pageserver.rs b/pageserver/src/bin/pageserver.rs
index a2cebffc83..e0731ba79b 100644
--- a/pageserver/src/bin/pageserver.rs
+++ b/pageserver/src/bin/pageserver.rs
@@ -335,9 +335,13 @@ fn start_pageserver(
     // Set up remote storage client
     let remote_storage = create_remote_storage_client(conf)?;
 
-    // All tenant load operations carry this while they are ongoing; it will be dropped once those
-    // operations finish either successfully or in some other manner. However, the initial load
-    // will be then done, and we can start the global background tasks.
+    // Startup staging or optimizing:
+    //
+    // (init_done_tx, init_done_rx) are used to control when do background loops start. This is to
+    // avoid starving out the BACKGROUND_RUNTIME async worker threads doing heavy work, like
+    // initial repartitioning while we still have Loading tenants.
+    //
+    // init_done_rx is a barrier which stops waiting once all init_done_tx clones are dropped.
     let (init_done_tx, init_done_rx) = utils::completion::channel();
 
     // Scan the local 'tenants/' directory and start loading the tenants
diff --git a/pageserver/src/http/routes.rs b/pageserver/src/http/routes.rs
index 61028e23fe..22dedbe5b2 100644
--- a/pageserver/src/http/routes.rs
+++ b/pageserver/src/http/routes.rs
@@ -1,3 +1,6 @@
+//!
+//! Management HTTP API
+//!
 use std::collections::HashMap;
 use std::sync::Arc;
 
@@ -46,7 +49,6 @@ use utils::{
 };
 
 // Imports only used for testing APIs
-#[cfg(feature = "testing")]
 use super::models::ConfigureFailpointsRequest;
 
 struct State {
@@ -290,13 +292,19 @@ fn build_timeline_info_common(
 }
 
 // healthcheck handler
-async fn status_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn status_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     check_permission(&request, None)?;
     let config = get_config(&request);
     json_response(StatusCode::OK, StatusResponse { id: config.id })
 }
 
-async fn timeline_create_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_create_handler(
+    mut request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let request_data: TimelineCreateRequest = json_request(&mut request).await?;
     check_permission(&request, Some(tenant_id))?;
@@ -332,7 +340,10 @@ async fn timeline_create_handler(mut request: Request<Body>) -> Result<Response<
     .await
 }
 
-async fn timeline_list_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_list_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let include_non_incremental_logical_size: Option<bool> =
         parse_query_param(&request, "include-non-incremental-logical-size")?;
@@ -366,7 +377,10 @@ async fn timeline_list_handler(request: Request<Body>) -> Result<Response<Body>,
     json_response(StatusCode::OK, response_data)
 }
 
-async fn timeline_detail_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_detail_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     let include_non_incremental_logical_size: Option<bool> =
@@ -400,7 +414,10 @@ async fn timeline_detail_handler(request: Request<Body>) -> Result<Response<Body
     json_response(StatusCode::OK, timeline_info)
 }
 
-async fn get_lsn_by_timestamp_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn get_lsn_by_timestamp_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -424,7 +441,10 @@ async fn get_lsn_by_timestamp_handler(request: Request<Body>) -> Result<Response
     json_response(StatusCode::OK, result)
 }
 
-async fn tenant_attach_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_attach_handler(
+    mut request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -460,7 +480,10 @@ async fn tenant_attach_handler(mut request: Request<Body>) -> Result<Response<Bo
     json_response(StatusCode::ACCEPTED, ())
 }
 
-async fn timeline_delete_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_delete_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
@@ -474,7 +497,10 @@ async fn timeline_delete_handler(request: Request<Body>) -> Result<Response<Body
     json_response(StatusCode::OK, ())
 }
 
-async fn tenant_detach_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_detach_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
     let detach_ignored: Option<bool> = parse_query_param(&request, "detach_ignored")?;
@@ -488,7 +514,10 @@ async fn tenant_detach_handler(request: Request<Body>) -> Result<Response<Body>,
     json_response(StatusCode::OK, ())
 }
 
-async fn tenant_load_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_load_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -508,7 +537,10 @@ async fn tenant_load_handler(request: Request<Body>) -> Result<Response<Body>, A
     json_response(StatusCode::ACCEPTED, ())
 }
 
-async fn tenant_ignore_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_ignore_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -521,7 +553,10 @@ async fn tenant_ignore_handler(request: Request<Body>) -> Result<Response<Body>,
     json_response(StatusCode::OK, ())
 }
 
-async fn tenant_list_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_list_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     check_permission(&request, None)?;
 
     let response_data = mgr::list_tenants()
@@ -541,7 +576,10 @@ async fn tenant_list_handler(request: Request<Body>) -> Result<Response<Body>, A
     json_response(StatusCode::OK, response_data)
 }
 
-async fn tenant_status(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_status(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -581,7 +619,10 @@ async fn tenant_status(request: Request<Body>) -> Result<Response<Body>, ApiErro
 /// Note: we don't update the cached size and prometheus metric here.
 /// The retention period might be different, and it's nice to have a method to just calculate it
 /// without modifying anything anyway.
-async fn tenant_size_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_size_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
     let inputs_only: Option<bool> = parse_query_param(&request, "inputs_only")?;
@@ -646,7 +687,10 @@ async fn tenant_size_handler(request: Request<Body>) -> Result<Response<Body>, A
     )
 }
 
-async fn layer_map_info_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn layer_map_info_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     let reset: LayerAccessStatsReset =
@@ -660,7 +704,10 @@ async fn layer_map_info_handler(request: Request<Body>) -> Result<Response<Body>
     json_response(StatusCode::OK, layer_map_info)
 }
 
-async fn layer_download_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn layer_download_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
@@ -683,7 +730,10 @@ async fn layer_download_handler(request: Request<Body>) -> Result<Response<Body>
     }
 }
 
-async fn evict_timeline_layer_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn evict_timeline_layer_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
@@ -761,7 +811,10 @@ pub fn html_response(status: StatusCode, data: String) -> Result<Response<Body>,
     Ok(response)
 }
 
-async fn tenant_create_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn tenant_create_handler(
+    mut request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let request_data: TenantCreateRequest = json_request(&mut request).await?;
     let target_tenant_id = request_data.new_tenant_id;
     check_permission(&request, None)?;
@@ -808,7 +861,10 @@ async fn tenant_create_handler(mut request: Request<Body>) -> Result<Response<Bo
     )
 }
 
-async fn get_tenant_config_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn get_tenant_config_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
@@ -834,6 +890,7 @@ async fn get_tenant_config_handler(request: Request<Body>) -> Result<Response<Bo
 
 async fn update_tenant_config_handler(
     mut request: Request<Body>,
+    _cancel: CancellationToken,
 ) -> Result<Response<Body>, ApiError> {
     let request_data: TenantConfigRequest = json_request(&mut request).await?;
     let tenant_id = request_data.tenant_id;
@@ -851,8 +908,10 @@ async fn update_tenant_config_handler(
 }
 
 /// Testing helper to transition a tenant to [`crate::tenant::TenantState::Broken`].
-#[cfg(feature = "testing")]
-async fn handle_tenant_break(r: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn handle_tenant_break(
+    r: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&r, "tenant_id")?;
 
     let tenant = crate::tenant::mgr::get_tenant(tenant_id, true)
@@ -864,8 +923,10 @@ async fn handle_tenant_break(r: Request<Body>) -> Result<Response<Body>, ApiErro
     json_response(StatusCode::OK, ())
 }
 
-#[cfg(feature = "testing")]
-async fn failpoints_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn failpoints_handler(
+    mut request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     if !fail::has_failpoints() {
         return Err(ApiError::BadRequest(anyhow!(
             "Cannot manage failpoints because pageserver was compiled without failpoints support"
@@ -898,7 +959,10 @@ async fn failpoints_handler(mut request: Request<Body>) -> Result<Response<Body>
 }
 
 // Run GC immediately on given timeline.
-async fn timeline_gc_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_gc_handler(
+    mut request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
@@ -917,8 +981,10 @@ async fn timeline_gc_handler(mut request: Request<Body>) -> Result<Response<Body
 }
 
 // Run compaction immediately on given timeline.
-#[cfg(feature = "testing")]
-async fn timeline_compact_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_compact_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
@@ -939,8 +1005,10 @@ async fn timeline_compact_handler(request: Request<Body>) -> Result<Response<Bod
 }
 
 // Run checkpoint immediately on given timeline.
-#[cfg(feature = "testing")]
-async fn timeline_checkpoint_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn timeline_checkpoint_handler(
+    request: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
@@ -964,6 +1032,7 @@ async fn timeline_checkpoint_handler(request: Request<Body>) -> Result<Response<
 
 async fn timeline_download_remote_layers_handler_post(
     mut request: Request<Body>,
+    _cancel: CancellationToken,
 ) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
@@ -979,6 +1048,7 @@ async fn timeline_download_remote_layers_handler_post(
 
 async fn timeline_download_remote_layers_handler_get(
     request: Request<Body>,
+    _cancel: CancellationToken,
 ) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
@@ -1002,7 +1072,10 @@ async fn active_timeline_of_active_tenant(
         .map_err(ApiError::NotFound)
 }
 
-async fn always_panic_handler(req: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn always_panic_handler(
+    req: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     // Deliberately cause a panic to exercise the panic hook registered via std::panic::set_hook().
     // For pageserver, the relevant panic hook is `tracing_panic_hook` , and the `sentry` crate's wrapper around it.
     // Use catch_unwind to ensure that tokio nor hyper are distracted by our panic.
@@ -1013,7 +1086,10 @@ async fn always_panic_handler(req: Request<Body>) -> Result<Response<Body>, ApiE
     json_response(StatusCode::NO_CONTENT, ())
 }
 
-async fn disk_usage_eviction_run(mut r: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn disk_usage_eviction_run(
+    mut r: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     check_permission(&r, None)?;
 
     #[derive(Debug, Clone, Copy, serde::Serialize, serde::Deserialize)]
@@ -1103,8 +1179,10 @@ async fn handler_404(_: Request<Body>) -> Result<Response<Body>, ApiError> {
     )
 }
 
-#[cfg(feature = "testing")]
-async fn post_tracing_event_handler(mut r: Request<Body>) -> Result<Response<Body>, ApiError> {
+async fn post_tracing_event_handler(
+    mut r: Request<Body>,
+    _cancel: CancellationToken,
+) -> Result<Response<Body>, ApiError> {
     #[derive(Debug, serde::Deserialize)]
     #[serde(rename_all = "lowercase")]
     enum Level {
@@ -1134,6 +1212,85 @@ async fn post_tracing_event_handler(mut r: Request<Body>) -> Result<Response<Bod
     json_response(StatusCode::OK, ())
 }
 
+/// Common functionality of all the HTTP API handlers.
+///
+/// - Adds a tracing span to each request (by `request_span`)
+/// - Logs the request depending on the request method (by `request_span`)
+/// - Logs the response if it was not successful (by `request_span`
+/// - Shields the handler function from async cancellations. Hyper can drop the handler
+///   Future if the connection to the client is lost, but most of the pageserver code is
+///   not async cancellation safe. This converts the dropped future into a graceful cancellation
+///   request with a CancellationToken.
+async fn api_handler<R, H>(request: Request<Body>, handler: H) -> Result<Response<Body>, ApiError>
+where
+    R: std::future::Future<Output = Result<Response<Body>, ApiError>> + Send + 'static,
+    H: FnOnce(Request<Body>, CancellationToken) -> R + Send + Sync + 'static,
+{
+    // Spawn a new task to handle the request, to protect the handler from unexpected
+    // async cancellations. Most pageserver functions are not async cancellation safe.
+    // We arm a drop-guard, so that if Hyper drops the Future, we signal the task
+    // with the cancellation token.
+    let token = CancellationToken::new();
+    let cancel_guard = token.clone().drop_guard();
+    let result = request_span(request, move |r| async {
+        let handle = tokio::spawn(
+            async {
+                let token_cloned = token.clone();
+                let result = handler(r, token).await;
+                if token_cloned.is_cancelled() {
+                    info!("Cancelled request finished");
+                }
+                result
+            }
+            .in_current_span(),
+        );
+
+        match handle.await {
+            Ok(result) => result,
+            Err(e) => {
+                // The handler task panicked. We have a global panic handler that logs the
+                // panic with its backtrace, so no need to log that here. Only log a brief
+                // message to make it clear that we returned the error to the client.
+                error!("HTTP request handler task panicked: {e:#}");
+
+                // Don't return an Error here, because then fallback error handler that was
+                // installed in make_router() will print the error. Instead, construct the
+                // HTTP error response and return that.
+                Ok(
+                    ApiError::InternalServerError(anyhow!("HTTP request handler task panicked"))
+                        .into_response(),
+                )
+            }
+        }
+    })
+    .await;
+
+    cancel_guard.disarm();
+
+    result
+}
+
+/// Like api_handler, but returns an error response if the server is built without
+/// the 'testing' feature.
+async fn testing_api_handler<R, H>(
+    desc: &str,
+    request: Request<Body>,
+    handler: H,
+) -> Result<Response<Body>, ApiError>
+where
+    R: std::future::Future<Output = Result<Response<Body>, ApiError>> + Send + 'static,
+    H: FnOnce(Request<Body>, CancellationToken) -> R + Send + Sync + 'static,
+{
+    if cfg!(feature = "testing") {
+        api_handler(request, handler).await
+    } else {
+        std::future::ready(Err(ApiError::BadRequest(anyhow!(
+            "Cannot {desc} because pageserver was compiled without testing APIs",
+        ))))
+        .await
+    }
+}
+
 pub fn make_router(
     conf: &'static PageServerConf,
     launch_ts: &'static LaunchTimestamp,
@@ -1163,26 +1320,6 @@ pub fn make_router(
         .expect("construct launch timestamp header middleware"),
     );
 
-    macro_rules! testing_api {
-        ($handler_desc:literal, $handler:path $(,)?) => {{
-            #[cfg(not(feature = "testing"))]
-            async fn cfg_disabled(_req: Request<Body>) -> Result<Response<Body>, ApiError> {
-                Err(ApiError::BadRequest(anyhow!(concat!(
-                    "Cannot ",
-                    $handler_desc,
-                    " because pageserver was compiled without testing APIs",
-                ))))
-            }
-
-            #[cfg(feature = "testing")]
-            let handler = $handler;
-            #[cfg(not(feature = "testing"))]
-            let handler = cfg_disabled;
-
-            move |r| request_span(r, handler)
-        }};
-    }
-
     Ok(router
         .data(Arc::new(
             State::new(
@@ -1194,92 +1331,88 @@ pub fn make_router(
             )
             .context("Failed to initialize router state")?,
         ))
-        .get("/v1/status", |r| request_span(r, status_handler))
-        .put(
-            "/v1/failpoints",
-            testing_api!("manage failpoints", failpoints_handler),
-        )
-        .get("/v1/tenant", |r| request_span(r, tenant_list_handler))
-        .post("/v1/tenant", |r| request_span(r, tenant_create_handler))
-        .get("/v1/tenant/:tenant_id", |r| request_span(r, tenant_status))
+        .get("/v1/status", |r| api_handler(r, status_handler))
+        .put("/v1/failpoints", |r| {
+            testing_api_handler("manage failpoints", r, failpoints_handler)
+        })
+        .get("/v1/tenant", |r| api_handler(r, tenant_list_handler))
+        .post("/v1/tenant", |r| api_handler(r, tenant_create_handler))
+        .get("/v1/tenant/:tenant_id", |r| api_handler(r, tenant_status))
         .get("/v1/tenant/:tenant_id/synthetic_size", |r| {
-            request_span(r, tenant_size_handler)
+            api_handler(r, tenant_size_handler)
         })
         .put("/v1/tenant/config", |r| {
-            request_span(r, update_tenant_config_handler)
+            api_handler(r, update_tenant_config_handler)
         })
         .get("/v1/tenant/:tenant_id/config", |r| {
-            request_span(r, get_tenant_config_handler)
+            api_handler(r, get_tenant_config_handler)
         })
         .get("/v1/tenant/:tenant_id/timeline", |r| {
-            request_span(r, timeline_list_handler)
+            api_handler(r, timeline_list_handler)
         })
         .post("/v1/tenant/:tenant_id/timeline", |r| {
-            request_span(r, timeline_create_handler)
+            api_handler(r, timeline_create_handler)
         })
         .post("/v1/tenant/:tenant_id/attach", |r| {
-            request_span(r, tenant_attach_handler)
+            api_handler(r, tenant_attach_handler)
         })
         .post("/v1/tenant/:tenant_id/detach", |r| {
-            request_span(r, tenant_detach_handler)
+            api_handler(r, tenant_detach_handler)
         })
         .post("/v1/tenant/:tenant_id/load", |r| {
-            request_span(r, tenant_load_handler)
+            api_handler(r, tenant_load_handler)
         })
         .post("/v1/tenant/:tenant_id/ignore", |r| {
-            request_span(r, tenant_ignore_handler)
+            api_handler(r, tenant_ignore_handler)
         })
         .get("/v1/tenant/:tenant_id/timeline/:timeline_id", |r| {
-            request_span(r, timeline_detail_handler)
+            api_handler(r, timeline_detail_handler)
         })
         .get(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/get_lsn_by_timestamp",
-            |r| request_span(r, get_lsn_by_timestamp_handler),
+            |r| api_handler(r, get_lsn_by_timestamp_handler),
         )
         .put("/v1/tenant/:tenant_id/timeline/:timeline_id/do_gc", |r| {
-            request_span(r, timeline_gc_handler)
+            api_handler(r, timeline_gc_handler)
+        })
+        .put("/v1/tenant/:tenant_id/timeline/:timeline_id/compact", |r| {
+            testing_api_handler("run timeline compaction", r, timeline_compact_handler)
         })
-        .put(
-            "/v1/tenant/:tenant_id/timeline/:timeline_id/compact",
-            testing_api!("run timeline compaction", timeline_compact_handler),
-        )
         .put(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/checkpoint",
-            testing_api!("run timeline checkpoint", timeline_checkpoint_handler),
+            |r| testing_api_handler("run timeline checkpoint", r, timeline_checkpoint_handler),
         )
         .post(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/download_remote_layers",
-            |r| request_span(r, timeline_download_remote_layers_handler_post),
+            |r| api_handler(r, timeline_download_remote_layers_handler_post),
         )
         .get(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/download_remote_layers",
-            |r| request_span(r, timeline_download_remote_layers_handler_get),
+            |r| api_handler(r, timeline_download_remote_layers_handler_get),
         )
         .delete("/v1/tenant/:tenant_id/timeline/:timeline_id", |r| {
-            request_span(r, timeline_delete_handler)
+            api_handler(r, timeline_delete_handler)
         })
         .get("/v1/tenant/:tenant_id/timeline/:timeline_id/layer", |r| {
-            request_span(r, layer_map_info_handler)
+            api_handler(r, layer_map_info_handler)
         })
         .get(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/layer/:layer_file_name",
-            |r| request_span(r, layer_download_handler),
+            |r| api_handler(r, layer_download_handler),
         )
         .delete(
             "/v1/tenant/:tenant_id/timeline/:timeline_id/layer/:layer_file_name",
-            |r| request_span(r, evict_timeline_layer_handler),
+            |r| api_handler(r, evict_timeline_layer_handler),
         )
         .put("/v1/disk_usage_eviction/run", |r| {
-            request_span(r, disk_usage_eviction_run)
+            api_handler(r, disk_usage_eviction_run)
+        })
+        .put("/v1/tenant/:tenant_id/break", |r| {
+            testing_api_handler("set tenant state to broken", r, handle_tenant_break)
+        })
+        .get("/v1/panic", |r| api_handler(r, always_panic_handler))
+        .post("/v1/tracing/event", |r| {
+            testing_api_handler("emit a tracing event", r, post_tracing_event_handler)
         })
-        .put(
-            "/v1/tenant/:tenant_id/break",
-            testing_api!("set tenant state to broken", handle_tenant_break),
-        )
-        .get("/v1/panic", |r| request_span(r, always_panic_handler))
-        .post(
-            "/v1/tracing/event",
-            testing_api!("emit a tracing event", post_tracing_event_handler),
-        )
         .any(handler_404))
 }
diff --git a/pageserver/src/metrics.rs b/pageserver/src/metrics.rs
index 75bea9dbab..cc444c479a 100644
--- a/pageserver/src/metrics.rs
+++ b/pageserver/src/metrics.rs
@@ -84,6 +84,16 @@ pub static STORAGE_TIME_GLOBAL: Lazy<HistogramVec> = Lazy::new(|| {
     .expect("failed to define a metric")
 });
 
+static READ_NUM_FS_LAYERS: Lazy<HistogramVec> = Lazy::new(|| {
+    register_histogram_vec!(
+        "pageserver_read_num_fs_layers",
+        "Number of persistent layers accessed for processing a read request, including those in the cache",
+        &["tenant_id", "timeline_id"],
+        vec![1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 10.0, 20.0, 50.0, 100.0],
+    )
+    .expect("failed to define a metric")
+});
+
 // Metrics collected on operations on the storage repository.
 static RECONSTRUCT_TIME: Lazy<HistogramVec> = Lazy::new(|| {
     register_histogram_vec!(
@@ -95,6 +105,25 @@ static RECONSTRUCT_TIME: Lazy<HistogramVec> = Lazy::new(|| {
     .expect("failed to define a metric")
 });
 
+static MATERIALIZED_PAGE_CACHE_HIT_DIRECT: Lazy<IntCounterVec> = Lazy::new(|| {
+    register_int_counter_vec!(
+        "pageserver_materialized_cache_hits_direct_total",
+        "Number of cache hits from materialized page cache without redo",
+        &["tenant_id", "timeline_id"]
+    )
+    .expect("failed to define a metric")
+});
+
+static GET_RECONSTRUCT_DATA_TIME: Lazy<HistogramVec> = Lazy::new(|| {
+    register_histogram_vec!(
+        "pageserver_getpage_get_reconstruct_data_seconds",
+        "Time spent in get_reconstruct_value_data",
+        &["tenant_id", "timeline_id"],
+        CRITICAL_OP_BUCKETS.into(),
+    )
+    .expect("failed to define a metric")
+});
+
 static MATERIALIZED_PAGE_CACHE_HIT: Lazy<IntCounterVec> = Lazy::new(|| {
     register_int_counter_vec!(
         "pageserver_materialized_cache_hits_total",
@@ -354,6 +383,7 @@ const STORAGE_IO_TIME_BUCKETS: &[f64] = &[
     0.001000, // 1000 usec
     0.030,    // 30 ms
     1.000,    // 1000 ms
+    30.000,   // 30000 ms
 ];
 
 const STORAGE_IO_TIME_OPERATIONS: &[&str] = &[
@@ -622,7 +652,7 @@ pub static WAL_REDO_TIME: Lazy<Histogram> = Lazy::new(|| {
 pub static WAL_REDO_WAIT_TIME: Lazy<Histogram> = Lazy::new(|| {
     register_histogram!(
         "pageserver_wal_redo_wait_seconds",
-        "Time spent waiting for access to the WAL redo process",
+        "Time spent waiting for access to the Postgres WAL redo process",
         redo_histogram_time_buckets!(),
     )
     .expect("failed to define a metric")
@@ -631,7 +661,7 @@ pub static WAL_REDO_WAIT_TIME: Lazy<Histogram> = Lazy::new(|| {
 pub static WAL_REDO_RECORDS_HISTOGRAM: Lazy<Histogram> = Lazy::new(|| {
     register_histogram!(
         "pageserver_wal_redo_records_histogram",
-        "Histogram of number of records replayed per redo",
+        "Histogram of number of records replayed per redo in the Postgres WAL redo process",
         redo_histogram_count_buckets!(),
     )
     .expect("failed to define a metric")
@@ -640,7 +670,7 @@ pub static WAL_REDO_RECORDS_HISTOGRAM: Lazy<Histogram> = Lazy::new(|| {
 pub static WAL_REDO_BYTES_HISTOGRAM: Lazy<Histogram> = Lazy::new(|| {
     register_histogram!(
         "pageserver_wal_redo_bytes_histogram",
-        "Histogram of number of records replayed per redo",
+        "Histogram of number of records replayed per redo sent to Postgres",
         redo_bytes_histogram_count_buckets!(),
     )
     .expect("failed to define a metric")
@@ -723,7 +753,9 @@ pub struct TimelineMetrics {
     tenant_id: String,
     timeline_id: String,
     pub reconstruct_time_histo: Histogram,
+    pub get_reconstruct_data_time_histo: Histogram,
     pub materialized_page_cache_hit_counter: GenericCounter<AtomicU64>,
+    pub materialized_page_cache_hit_upon_request_counter: GenericCounter<AtomicU64>,
     pub flush_time_histo: StorageTimeMetrics,
     pub compact_time_histo: StorageTimeMetrics,
     pub create_images_time_histo: StorageTimeMetrics,
@@ -734,6 +766,7 @@ pub struct TimelineMetrics {
     pub last_record_gauge: IntGauge,
     pub wait_lsn_time_histo: Histogram,
     pub resident_physical_size_gauge: UIntGauge,
+    pub read_num_fs_layers: Histogram,
     /// copy of LayeredTimeline.current_logical_size
     pub current_logical_size_gauge: UIntGauge,
     pub num_persistent_files_created: IntCounter,
@@ -753,6 +786,9 @@ impl TimelineMetrics {
         let reconstruct_time_histo = RECONSTRUCT_TIME
             .get_metric_with_label_values(&[&tenant_id, &timeline_id])
             .unwrap();
+        let get_reconstruct_data_time_histo = GET_RECONSTRUCT_DATA_TIME
+            .get_metric_with_label_values(&[&tenant_id, &timeline_id])
+            .unwrap();
         let materialized_page_cache_hit_counter = MATERIALIZED_PAGE_CACHE_HIT
             .get_metric_with_label_values(&[&tenant_id, &timeline_id])
             .unwrap();
@@ -794,6 +830,12 @@ impl TimelineMetrics {
         let evictions = EVICTIONS
             .get_metric_with_label_values(&[&tenant_id, &timeline_id])
             .unwrap();
+        let read_num_fs_layers = READ_NUM_FS_LAYERS
+            .get_metric_with_label_values(&[&tenant_id, &timeline_id])
+            .unwrap();
+        let materialized_page_cache_hit_upon_request_counter = MATERIALIZED_PAGE_CACHE_HIT_DIRECT
+            .get_metric_with_label_values(&[&tenant_id, &timeline_id])
+            .unwrap();
         let evictions_with_low_residence_duration =
             evictions_with_low_residence_duration_builder.build(&tenant_id, &timeline_id);
 
@@ -801,7 +843,9 @@ impl TimelineMetrics {
             tenant_id,
             timeline_id,
             reconstruct_time_histo,
+            get_reconstruct_data_time_histo,
             materialized_page_cache_hit_counter,
+            materialized_page_cache_hit_upon_request_counter,
             flush_time_histo,
             compact_time_histo,
             create_images_time_histo,
@@ -819,6 +863,7 @@ impl TimelineMetrics {
             evictions_with_low_residence_duration: std::sync::RwLock::new(
                 evictions_with_low_residence_duration,
             ),
+            read_num_fs_layers,
         }
     }
 }
@@ -828,7 +873,9 @@ impl Drop for TimelineMetrics {
         let tenant_id = &self.tenant_id;
         let timeline_id = &self.timeline_id;
         let _ = RECONSTRUCT_TIME.remove_label_values(&[tenant_id, timeline_id]);
+        let _ = GET_RECONSTRUCT_DATA_TIME.remove_label_values(&[tenant_id, timeline_id]);
         let _ = MATERIALIZED_PAGE_CACHE_HIT.remove_label_values(&[tenant_id, timeline_id]);
+        let _ = MATERIALIZED_PAGE_CACHE_HIT_DIRECT.remove_label_values(&[tenant_id, timeline_id]);
         let _ = LAST_RECORD_LSN.remove_label_values(&[tenant_id, timeline_id]);
         let _ = WAIT_LSN_TIME.remove_label_values(&[tenant_id, timeline_id]);
         let _ = RESIDENT_PHYSICAL_SIZE.remove_label_values(&[tenant_id, timeline_id]);
@@ -836,6 +883,8 @@ impl Drop for TimelineMetrics {
         let _ = NUM_PERSISTENT_FILES_CREATED.remove_label_values(&[tenant_id, timeline_id]);
         let _ = PERSISTENT_BYTES_WRITTEN.remove_label_values(&[tenant_id, timeline_id]);
         let _ = EVICTIONS.remove_label_values(&[tenant_id, timeline_id]);
+        let _ = READ_NUM_FS_LAYERS.remove_label_values(&[tenant_id, timeline_id]);
+
         self.evictions_with_low_residence_duration
             .write()
             .unwrap()
diff --git a/pageserver/src/tenant.rs b/pageserver/src/tenant.rs
index af6a70c4f2..bcf4495ac2 100644
--- a/pageserver/src/tenant.rs
+++ b/pageserver/src/tenant.rs
@@ -267,7 +267,7 @@ impl UninitializedTimeline<'_> {
         // updated it for the layers that we created during the import.
         let mut timelines = self.owning_tenant.timelines.lock().unwrap();
         let tl = self.initialize_with_lock(ctx, &mut timelines, false)?;
-        tl.activate(broker_client, ctx);
+        tl.activate(broker_client, None, ctx);
         Ok(tl)
     }
 
@@ -879,7 +879,6 @@ impl Tenant {
         ))
     }
 
-    ///
     /// Load a tenant that's available on local disk
     ///
     /// This is used at pageserver startup, to rebuild the in-memory
@@ -890,6 +889,8 @@ impl Tenant {
     /// If the loading fails for some reason, the Tenant will go into Broken
     /// state.
     ///
+    /// `init_done` is an optional channel used during initial load to delay background task
+    /// start. It is not used later.
     #[instrument(skip_all, fields(tenant_id=%tenant_id))]
     pub fn spawn_load(
         conf: &'static PageServerConf,
@@ -1358,7 +1359,7 @@ impl Tenant {
             }
         };
 
-        loaded_timeline.activate(broker_client, ctx);
+        loaded_timeline.activate(broker_client, None, ctx);
 
         if let Some(remote_client) = loaded_timeline.remote_client.as_ref() {
             // Wait for the upload of the 'index_part.json` file to finish, so that when we return
@@ -1394,6 +1395,7 @@ impl Tenant {
         pitr: Duration,
         ctx: &RequestContext,
     ) -> anyhow::Result<GcResult> {
+        // there is a global allowed_error for this
         anyhow::ensure!(
             self.is_active(),
             "Cannot run GC iteration on inactive tenant"
@@ -1682,6 +1684,9 @@ impl Tenant {
     }
 
     /// Changes tenant status to active, unless shutdown was already requested.
+    ///
+    /// `init_done` is an optional channel used during initial load to delay background task
+    /// start. It is not used later.
     fn activate(
         self: &Arc<Self>,
         broker_client: BrokerClientChannel,
@@ -1723,7 +1728,7 @@ impl Tenant {
             let mut activated_timelines = 0;
 
             for timeline in not_broken_timelines {
-                timeline.activate(broker_client.clone(), ctx);
+                timeline.activate(broker_client.clone(), init_done, ctx);
                 activated_timelines += 1;
             }
 
diff --git a/pageserver/src/tenant/mgr.rs b/pageserver/src/tenant/mgr.rs
index d3cd914037..05874bdd72 100644
--- a/pageserver/src/tenant/mgr.rs
+++ b/pageserver/src/tenant/mgr.rs
@@ -155,6 +155,8 @@ pub async fn init_tenant_mgr(
     Ok(())
 }
 
+/// `init_done` is an optional channel used during initial load to delay background task
+/// start. It is not used later.
 pub fn schedule_local_tenant_processing(
     conf: &'static PageServerConf,
     tenant_path: &Path,
@@ -779,7 +781,6 @@ pub async fn immediate_gc(
     Ok(wait_task_done)
 }
 
-#[cfg(feature = "testing")]
 pub async fn immediate_compact(
     tenant_id: TenantId,
     timeline_id: TimelineId,
diff --git a/pageserver/src/tenant/storage_layer.rs b/pageserver/src/tenant/storage_layer.rs
index 3ca8e28c16..7c071463de 100644
--- a/pageserver/src/tenant/storage_layer.rs
+++ b/pageserver/src/tenant/storage_layer.rs
@@ -4,6 +4,7 @@ pub mod delta_layer;
 mod filename;
 mod image_layer;
 mod inmemory_layer;
+mod layer_desc;
 mod remote_layer;
 
 use crate::config::PageServerConf;
@@ -37,6 +38,7 @@ pub use delta_layer::{DeltaLayer, DeltaLayerWriter};
 pub use filename::{DeltaFileName, ImageFileName, LayerFileName};
 pub use image_layer::{ImageLayer, ImageLayerWriter};
 pub use inmemory_layer::InMemoryLayer;
+pub use layer_desc::PersistentLayerDesc;
 pub use remote_layer::RemoteLayer;
 
 use super::layer_map::BatchedUpdates;
@@ -406,14 +408,23 @@ pub type LayerKeyIter<'i> = Box<dyn Iterator<Item = (Key, Lsn, u64)> + 'i>;
 /// An image layer is a snapshot of all the data in a key-range, at a single
 /// LSN.
 pub trait PersistentLayer: Layer {
-    fn get_tenant_id(&self) -> TenantId;
+    /// Get the layer descriptor.
+    fn layer_desc(&self) -> &PersistentLayerDesc;
+
+    fn get_tenant_id(&self) -> TenantId {
+        self.layer_desc().tenant_id
+    }
 
     /// Identify the timeline this layer belongs to
-    fn get_timeline_id(&self) -> TimelineId;
+    fn get_timeline_id(&self) -> TimelineId {
+        self.layer_desc().timeline_id
+    }
 
     /// File name used for this layer, both in the pageserver's local filesystem
     /// state as well as in the remote storage.
-    fn filename(&self) -> LayerFileName;
+    fn filename(&self) -> LayerFileName {
+        self.layer_desc().filename()
+    }
 
     // Path to the layer file in the local filesystem.
     // `None` for `RemoteLayer`.
diff --git a/pageserver/src/tenant/storage_layer/delta_layer.rs b/pageserver/src/tenant/storage_layer/delta_layer.rs
index 63b8e57bb0..5f2fb1ebea 100644
--- a/pageserver/src/tenant/storage_layer/delta_layer.rs
+++ b/pageserver/src/tenant/storage_layer/delta_layer.rs
@@ -56,8 +56,8 @@ use utils::{
 };
 
 use super::{
-    DeltaFileName, Layer, LayerAccessStats, LayerAccessStatsReset, LayerFileName, LayerIter,
-    LayerKeyIter, PathOrConf,
+    DeltaFileName, Layer, LayerAccessStats, LayerAccessStatsReset, LayerIter, LayerKeyIter,
+    PathOrConf, PersistentLayerDesc,
 };
 
 ///
@@ -89,10 +89,10 @@ impl From<&DeltaLayer> for Summary {
             magic: DELTA_FILE_MAGIC,
             format_version: STORAGE_FORMAT_VERSION,
 
-            tenant_id: layer.tenant_id,
-            timeline_id: layer.timeline_id,
-            key_range: layer.key_range.clone(),
-            lsn_range: layer.lsn_range.clone(),
+            tenant_id: layer.desc.tenant_id,
+            timeline_id: layer.desc.timeline_id,
+            key_range: layer.desc.key_range.clone(),
+            lsn_range: layer.desc.lsn_range.clone(),
 
             index_start_blk: 0,
             index_root_blk: 0,
@@ -180,10 +180,7 @@ impl DeltaKey {
 pub struct DeltaLayer {
     path_or_conf: PathOrConf,
 
-    pub tenant_id: TenantId,
-    pub timeline_id: TimelineId,
-    pub key_range: Range<Key>,
-    pub lsn_range: Range<Lsn>,
+    pub desc: PersistentLayerDesc,
 
     pub file_size: u64,
 
@@ -197,8 +194,8 @@ impl std::fmt::Debug for DeltaLayer {
         use super::RangeDisplayDebug;
 
         f.debug_struct("DeltaLayer")
-            .field("key_range", &RangeDisplayDebug(&self.key_range))
-            .field("lsn_range", &self.lsn_range)
+            .field("key_range", &RangeDisplayDebug(&self.desc.key_range))
+            .field("lsn_range", &self.desc.lsn_range)
             .field("file_size", &self.file_size)
             .field("inner", &self.inner)
             .finish()
@@ -228,30 +225,16 @@ impl std::fmt::Debug for DeltaLayerInner {
 }
 
 impl Layer for DeltaLayer {
-    fn get_key_range(&self) -> Range<Key> {
-        self.key_range.clone()
-    }
-
-    fn get_lsn_range(&self) -> Range<Lsn> {
-        self.lsn_range.clone()
-    }
-    fn is_incremental(&self) -> bool {
-        true
-    }
-
-    fn short_id(&self) -> String {
-        self.filename().file_name()
-    }
     /// debugging function to print out the contents of the layer
     fn dump(&self, verbose: bool, ctx: &RequestContext) -> Result<()> {
         println!(
             "----- delta layer for ten {} tli {} keys {}-{} lsn {}-{} ----",
-            self.tenant_id,
-            self.timeline_id,
-            self.key_range.start,
-            self.key_range.end,
-            self.lsn_range.start,
-            self.lsn_range.end
+            self.desc.tenant_id,
+            self.desc.timeline_id,
+            self.desc.key_range.start,
+            self.desc.key_range.end,
+            self.desc.lsn_range.start,
+            self.desc.lsn_range.end
         );
 
         if !verbose {
@@ -324,10 +307,10 @@ impl Layer for DeltaLayer {
         reconstruct_state: &mut ValueReconstructState,
         ctx: &RequestContext,
     ) -> anyhow::Result<ValueReconstructResult> {
-        ensure!(lsn_range.start >= self.lsn_range.start);
+        ensure!(lsn_range.start >= self.desc.lsn_range.start);
         let mut need_image = true;
 
-        ensure!(self.key_range.contains(&key));
+        ensure!(self.desc.key_range.contains(&key));
 
         {
             // Open the file and lock the metadata in memory
@@ -402,19 +385,31 @@ impl Layer for DeltaLayer {
             Ok(ValueReconstructResult::Complete)
         }
     }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_key_range(&self) -> Range<Key> {
+        self.layer_desc().key_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_lsn_range(&self) -> Range<Lsn> {
+        self.layer_desc().lsn_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn is_incremental(&self) -> bool {
+        self.layer_desc().is_incremental
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn short_id(&self) -> String {
+        self.layer_desc().short_id()
+    }
 }
 
 impl PersistentLayer for DeltaLayer {
-    fn get_tenant_id(&self) -> TenantId {
-        self.tenant_id
-    }
-
-    fn get_timeline_id(&self) -> TimelineId {
-        self.timeline_id
-    }
-
-    fn filename(&self) -> LayerFileName {
-        self.layer_name().into()
+    fn layer_desc(&self) -> &PersistentLayerDesc {
+        &self.desc
     }
 
     fn local_path(&self) -> Option<PathBuf> {
@@ -602,10 +597,12 @@ impl DeltaLayer {
     ) -> DeltaLayer {
         DeltaLayer {
             path_or_conf: PathOrConf::Conf(conf),
-            timeline_id,
-            tenant_id,
-            key_range: filename.key_range.clone(),
-            lsn_range: filename.lsn_range.clone(),
+            desc: PersistentLayerDesc::new_delta(
+                tenant_id,
+                timeline_id,
+                filename.key_range.clone(),
+                filename.lsn_range.clone(),
+            ),
             file_size,
             access_stats,
             inner: RwLock::new(DeltaLayerInner {
@@ -632,10 +629,12 @@ impl DeltaLayer {
 
         Ok(DeltaLayer {
             path_or_conf: PathOrConf::Path(path.to_path_buf()),
-            timeline_id: summary.timeline_id,
-            tenant_id: summary.tenant_id,
-            key_range: summary.key_range,
-            lsn_range: summary.lsn_range,
+            desc: PersistentLayerDesc::new_delta(
+                summary.tenant_id,
+                summary.timeline_id,
+                summary.key_range,
+                summary.lsn_range,
+            ),
             file_size: metadata.len(),
             access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
             inner: RwLock::new(DeltaLayerInner {
@@ -648,18 +647,14 @@ impl DeltaLayer {
     }
 
     fn layer_name(&self) -> DeltaFileName {
-        DeltaFileName {
-            key_range: self.key_range.clone(),
-            lsn_range: self.lsn_range.clone(),
-        }
+        self.desc.delta_file_name()
     }
-
     /// Path to the layer file in pageserver workdir.
     pub fn path(&self) -> PathBuf {
         Self::path_for(
             &self.path_or_conf,
-            self.timeline_id,
-            self.tenant_id,
+            self.desc.timeline_id,
+            self.desc.tenant_id,
             &self.layer_name(),
         )
     }
@@ -803,10 +798,12 @@ impl DeltaLayerWriterInner {
         // set inner.file here. The first read will have to re-open it.
         let layer = DeltaLayer {
             path_or_conf: PathOrConf::Conf(self.conf),
-            tenant_id: self.tenant_id,
-            timeline_id: self.timeline_id,
-            key_range: self.key_start..key_end,
-            lsn_range: self.lsn_range.clone(),
+            desc: PersistentLayerDesc::new_delta(
+                self.tenant_id,
+                self.timeline_id,
+                self.key_start..key_end,
+                self.lsn_range.clone(),
+            ),
             file_size: metadata.len(),
             access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
             inner: RwLock::new(DeltaLayerInner {
diff --git a/pageserver/src/tenant/storage_layer/filename.rs b/pageserver/src/tenant/storage_layer/filename.rs
index e2112fc388..5dcd54689e 100644
--- a/pageserver/src/tenant/storage_layer/filename.rs
+++ b/pageserver/src/tenant/storage_layer/filename.rs
@@ -9,6 +9,8 @@ use std::str::FromStr;
 
 use utils::lsn::Lsn;
 
+use super::PersistentLayerDesc;
+
 // Note: Timeline::load_layer_map() relies on this sort order
 #[derive(PartialEq, Eq, Clone, Hash)]
 pub struct DeltaFileName {
@@ -153,7 +155,7 @@ impl Ord for ImageFileName {
 impl ImageFileName {
     pub fn lsn_as_range(&self) -> Range<Lsn> {
         // Saves from having to copypaste this all over
-        self.lsn..(self.lsn + 1)
+        PersistentLayerDesc::image_layer_lsn_range(self.lsn)
     }
 }
 
diff --git a/pageserver/src/tenant/storage_layer/image_layer.rs b/pageserver/src/tenant/storage_layer/image_layer.rs
index a5dd16fae2..b55dd08a6d 100644
--- a/pageserver/src/tenant/storage_layer/image_layer.rs
+++ b/pageserver/src/tenant/storage_layer/image_layer.rs
@@ -52,8 +52,8 @@ use utils::{
     lsn::Lsn,
 };
 
-use super::filename::{ImageFileName, LayerFileName};
-use super::{Layer, LayerAccessStatsReset, LayerIter, PathOrConf};
+use super::filename::ImageFileName;
+use super::{Layer, LayerAccessStatsReset, LayerIter, PathOrConf, PersistentLayerDesc};
 
 ///
 /// Header stored in the beginning of the file
@@ -84,9 +84,9 @@ impl From<&ImageLayer> for Summary {
         Self {
             magic: IMAGE_FILE_MAGIC,
             format_version: STORAGE_FORMAT_VERSION,
-            tenant_id: layer.tenant_id,
-            timeline_id: layer.timeline_id,
-            key_range: layer.key_range.clone(),
+            tenant_id: layer.desc.tenant_id,
+            timeline_id: layer.desc.timeline_id,
+            key_range: layer.desc.key_range.clone(),
             lsn: layer.lsn,
 
             index_start_blk: 0,
@@ -104,14 +104,13 @@ impl From<&ImageLayer> for Summary {
 /// and it needs to be loaded before using it in queries.
 pub struct ImageLayer {
     path_or_conf: PathOrConf,
-    pub tenant_id: TenantId,
-    pub timeline_id: TimelineId,
-    pub key_range: Range<Key>,
-    pub file_size: u64,
 
-    // This entry contains an image of all pages as of this LSN
+    pub desc: PersistentLayerDesc,
+    // This entry contains an image of all pages as of this LSN, should be the same as desc.lsn
     pub lsn: Lsn,
 
+    pub file_size: u64,
+
     access_stats: LayerAccessStats,
 
     inner: RwLock<ImageLayerInner>,
@@ -122,7 +121,7 @@ impl std::fmt::Debug for ImageLayer {
         use super::RangeDisplayDebug;
 
         f.debug_struct("ImageLayer")
-            .field("key_range", &RangeDisplayDebug(&self.key_range))
+            .field("key_range", &RangeDisplayDebug(&self.desc.key_range))
             .field("file_size", &self.file_size)
             .field("lsn", &self.lsn)
             .field("inner", &self.inner)
@@ -153,27 +152,15 @@ impl std::fmt::Debug for ImageLayerInner {
 }
 
 impl Layer for ImageLayer {
-    fn get_key_range(&self) -> Range<Key> {
-        self.key_range.clone()
-    }
-
-    fn get_lsn_range(&self) -> Range<Lsn> {
-        // End-bound is exclusive
-        self.lsn..(self.lsn + 1)
-    }
-    fn is_incremental(&self) -> bool {
-        false
-    }
-
-    fn short_id(&self) -> String {
-        self.filename().file_name()
-    }
-
     /// debugging function to print out the contents of the layer
     fn dump(&self, verbose: bool, ctx: &RequestContext) -> Result<()> {
         println!(
             "----- image layer for ten {} tli {} key {}-{} at {} ----",
-            self.tenant_id, self.timeline_id, self.key_range.start, self.key_range.end, self.lsn
+            self.desc.tenant_id,
+            self.desc.timeline_id,
+            self.desc.key_range.start,
+            self.desc.key_range.end,
+            self.lsn
         );
 
         if !verbose {
@@ -203,7 +190,7 @@ impl Layer for ImageLayer {
         reconstruct_state: &mut ValueReconstructState,
         ctx: &RequestContext,
     ) -> anyhow::Result<ValueReconstructResult> {
-        assert!(self.key_range.contains(&key));
+        assert!(self.desc.key_range.contains(&key));
         assert!(lsn_range.start >= self.lsn);
         assert!(lsn_range.end >= self.lsn);
 
@@ -230,24 +217,37 @@ impl Layer for ImageLayer {
             Ok(ValueReconstructResult::Missing)
         }
     }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_key_range(&self) -> Range<Key> {
+        self.layer_desc().key_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_lsn_range(&self) -> Range<Lsn> {
+        self.layer_desc().lsn_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn is_incremental(&self) -> bool {
+        self.layer_desc().is_incremental
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn short_id(&self) -> String {
+        self.layer_desc().short_id()
+    }
 }
 
 impl PersistentLayer for ImageLayer {
-    fn filename(&self) -> LayerFileName {
-        self.layer_name().into()
+    fn layer_desc(&self) -> &PersistentLayerDesc {
+        &self.desc
     }
 
     fn local_path(&self) -> Option<PathBuf> {
         Some(self.path())
     }
 
-    fn get_tenant_id(&self) -> TenantId {
-        self.tenant_id
-    }
-
-    fn get_timeline_id(&self) -> TimelineId {
-        self.timeline_id
-    }
     fn iter(&self, _ctx: &RequestContext) -> Result<LayerIter<'_>> {
         unimplemented!();
     }
@@ -405,9 +405,13 @@ impl ImageLayer {
     ) -> ImageLayer {
         ImageLayer {
             path_or_conf: PathOrConf::Conf(conf),
-            timeline_id,
-            tenant_id,
-            key_range: filename.key_range.clone(),
+            desc: PersistentLayerDesc::new_img(
+                tenant_id,
+                timeline_id,
+                filename.key_range.clone(),
+                filename.lsn,
+                false,
+            ), // Now we assume image layer ALWAYS covers the full range. This may change in the future.
             lsn: filename.lsn,
             file_size,
             access_stats,
@@ -433,9 +437,13 @@ impl ImageLayer {
             .context("get file metadata to determine size")?;
         Ok(ImageLayer {
             path_or_conf: PathOrConf::Path(path.to_path_buf()),
-            timeline_id: summary.timeline_id,
-            tenant_id: summary.tenant_id,
-            key_range: summary.key_range,
+            desc: PersistentLayerDesc::new_img(
+                summary.tenant_id,
+                summary.timeline_id,
+                summary.key_range,
+                summary.lsn,
+                false,
+            ), // Now we assume image layer ALWAYS covers the full range. This may change in the future.
             lsn: summary.lsn,
             file_size: metadata.len(),
             access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
@@ -449,18 +457,15 @@ impl ImageLayer {
     }
 
     fn layer_name(&self) -> ImageFileName {
-        ImageFileName {
-            key_range: self.key_range.clone(),
-            lsn: self.lsn,
-        }
+        self.desc.image_file_name()
     }
 
     /// Path to the layer file in pageserver workdir.
     pub fn path(&self) -> PathBuf {
         Self::path_for(
             &self.path_or_conf,
-            self.timeline_id,
-            self.tenant_id,
+            self.desc.timeline_id,
+            self.desc.tenant_id,
             &self.layer_name(),
         )
     }
@@ -484,6 +489,7 @@ struct ImageLayerWriterInner {
     tenant_id: TenantId,
     key_range: Range<Key>,
     lsn: Lsn,
+    is_incremental: bool,
 
     blob_writer: WriteBlobWriter<VirtualFile>,
     tree: DiskBtreeBuilder<BlockBuf, KEY_SIZE>,
@@ -499,6 +505,7 @@ impl ImageLayerWriterInner {
         tenant_id: TenantId,
         key_range: &Range<Key>,
         lsn: Lsn,
+        is_incremental: bool,
     ) -> anyhow::Result<Self> {
         // Create the file initially with a temporary filename.
         // We'll atomically rename it to the final name when we're done.
@@ -533,6 +540,7 @@ impl ImageLayerWriterInner {
             lsn,
             tree: tree_builder,
             blob_writer,
+            is_incremental,
         };
 
         Ok(writer)
@@ -570,6 +578,14 @@ impl ImageLayerWriterInner {
             file.write_all(buf.as_ref())?;
         }
 
+        let desc = PersistentLayerDesc::new_img(
+            self.tenant_id,
+            self.timeline_id,
+            self.key_range.clone(),
+            self.lsn,
+            self.is_incremental, // for now, image layer ALWAYS covers the full range
+        );
+
         // Fill in the summary on blk 0
         let summary = Summary {
             magic: IMAGE_FILE_MAGIC,
@@ -593,9 +609,7 @@ impl ImageLayerWriterInner {
         // set inner.file here. The first read will have to re-open it.
         let layer = ImageLayer {
             path_or_conf: PathOrConf::Conf(self.conf),
-            timeline_id: self.timeline_id,
-            tenant_id: self.tenant_id,
-            key_range: self.key_range.clone(),
+            desc,
             lsn: self.lsn,
             file_size: metadata.len(),
             access_stats: LayerAccessStats::empty_will_record_residence_event_later(),
@@ -667,6 +681,7 @@ impl ImageLayerWriter {
         tenant_id: TenantId,
         key_range: &Range<Key>,
         lsn: Lsn,
+        is_incremental: bool,
     ) -> anyhow::Result<ImageLayerWriter> {
         Ok(Self {
             inner: Some(ImageLayerWriterInner::new(
@@ -675,6 +690,7 @@ impl ImageLayerWriter {
                 tenant_id,
                 key_range,
                 lsn,
+                is_incremental,
             )?),
         })
     }
diff --git a/pageserver/src/tenant/storage_layer/layer_desc.rs b/pageserver/src/tenant/storage_layer/layer_desc.rs
new file mode 100644
index 0000000000..a9859681d3
--- /dev/null
+++ b/pageserver/src/tenant/storage_layer/layer_desc.rs
@@ -0,0 +1,109 @@
+use std::ops::Range;
+use utils::{
+    id::{TenantId, TimelineId},
+    lsn::Lsn,
+};
+
+use crate::repository::Key;
+
+use super::{DeltaFileName, ImageFileName, LayerFileName};
+
+/// A unique identifier of a persistent layer. This is different from `LayerDescriptor`, which is only used in the
+/// benchmarks. This struct contains all necessary information to find the image / delta layer. It also provides
+/// a unified way to generate layer information like file name.
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct PersistentLayerDesc {
+    pub tenant_id: TenantId,
+    pub timeline_id: TimelineId,
+    pub key_range: Range<Key>,
+    /// For image layer, this is `[lsn, lsn+1)`.
+    pub lsn_range: Range<Lsn>,
+    /// Whether this is a delta layer.
+    pub is_delta: bool,
+    /// Whether this layer only contains page images for part of the keys in the range. In the current implementation, this should
+    /// always be equal to `is_delta`. If we land the partial image layer PR someday, image layer could also be
+    /// incremental.
+    pub is_incremental: bool,
+}
+
+impl PersistentLayerDesc {
+    pub fn short_id(&self) -> String {
+        self.filename().file_name()
+    }
+
+    pub fn new_img(
+        tenant_id: TenantId,
+        timeline_id: TimelineId,
+        key_range: Range<Key>,
+        lsn: Lsn,
+        is_incremental: bool,
+    ) -> Self {
+        Self {
+            tenant_id,
+            timeline_id,
+            key_range,
+            lsn_range: Self::image_layer_lsn_range(lsn),
+            is_delta: false,
+            is_incremental,
+        }
+    }
+
+    pub fn new_delta(
+        tenant_id: TenantId,
+        timeline_id: TimelineId,
+        key_range: Range<Key>,
+        lsn_range: Range<Lsn>,
+    ) -> Self {
+        Self {
+            tenant_id,
+            timeline_id,
+            key_range,
+            lsn_range,
+            is_delta: true,
+            is_incremental: true,
+        }
+    }
+
+    /// Get the LSN that the image layer covers.
+    pub fn image_layer_lsn(&self) -> Lsn {
+        assert!(!self.is_delta);
+        assert!(self.lsn_range.start + 1 == self.lsn_range.end);
+        self.lsn_range.start
+    }
+
+    /// Get the LSN range corresponding to a single image layer LSN.
+    pub fn image_layer_lsn_range(lsn: Lsn) -> Range<Lsn> {
+        lsn..(lsn + 1)
+    }
+
+    /// Get a delta file name for this layer.
+    ///
+    /// Panic: if this is not a delta layer.
+    pub fn delta_file_name(&self) -> DeltaFileName {
+        assert!(self.is_delta);
+        DeltaFileName {
+            key_range: self.key_range.clone(),
+            lsn_range: self.lsn_range.clone(),
+        }
+    }
+
+    /// Get a delta file name for this layer.
+    ///
+    /// Panic: if this is not an image layer, or the lsn range is invalid
+    pub fn image_file_name(&self) -> ImageFileName {
+        assert!(!self.is_delta);
+        assert!(self.lsn_range.start + 1 == self.lsn_range.end);
+        ImageFileName {
+            key_range: self.key_range.clone(),
+            lsn: self.lsn_range.start,
+        }
+    }
+
+    pub fn filename(&self) -> LayerFileName {
+        if self.is_delta {
+            self.delta_file_name().into()
+        } else {
+            self.image_file_name().into()
+        }
+    }
+}
diff --git a/pageserver/src/tenant/storage_layer/remote_layer.rs b/pageserver/src/tenant/storage_layer/remote_layer.rs
index 2106587ab2..ff0f44da92 100644
--- a/pageserver/src/tenant/storage_layer/remote_layer.rs
+++ b/pageserver/src/tenant/storage_layer/remote_layer.rs
@@ -18,11 +18,10 @@ use utils::{
     lsn::Lsn,
 };
 
-use super::filename::{DeltaFileName, ImageFileName, LayerFileName};
-use super::image_layer::ImageLayer;
+use super::filename::{DeltaFileName, ImageFileName};
 use super::{
-    DeltaLayer, LayerAccessStats, LayerAccessStatsReset, LayerIter, LayerKeyIter,
-    LayerResidenceStatus, PersistentLayer,
+    DeltaLayer, ImageLayer, LayerAccessStats, LayerAccessStatsReset, LayerIter, LayerKeyIter,
+    LayerResidenceStatus, PersistentLayer, PersistentLayerDesc,
 };
 
 /// RemoteLayer is a not yet downloaded [`ImageLayer`] or
@@ -34,19 +33,10 @@ use super::{
 ///
 /// See: [`crate::context::RequestContext`] for authorization to download
 pub struct RemoteLayer {
-    tenantid: TenantId,
-    timelineid: TimelineId,
-    key_range: Range<Key>,
-    lsn_range: Range<Lsn>,
-
-    pub file_name: LayerFileName,
+    pub desc: PersistentLayerDesc,
 
     pub layer_metadata: LayerFileMetadata,
 
-    is_delta: bool,
-
-    is_incremental: bool,
-
     access_stats: LayerAccessStats,
 
     pub(crate) ongoing_download: Arc<tokio::sync::Semaphore>,
@@ -66,22 +56,14 @@ pub struct RemoteLayer {
 impl std::fmt::Debug for RemoteLayer {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("RemoteLayer")
-            .field("file_name", &self.file_name)
+            .field("file_name", &self.desc.filename())
             .field("layer_metadata", &self.layer_metadata)
-            .field("is_incremental", &self.is_incremental)
+            .field("is_incremental", &self.desc.is_incremental)
             .finish()
     }
 }
 
 impl Layer for RemoteLayer {
-    fn get_key_range(&self) -> Range<Key> {
-        self.key_range.clone()
-    }
-
-    fn get_lsn_range(&self) -> Range<Lsn> {
-        self.lsn_range.clone()
-    }
-
     fn get_value_reconstruct_data(
         &self,
         _key: Key,
@@ -95,53 +77,45 @@ impl Layer for RemoteLayer {
         );
     }
 
-    fn is_incremental(&self) -> bool {
-        self.is_incremental
-    }
-
     /// debugging function to print out the contents of the layer
     fn dump(&self, _verbose: bool, _ctx: &RequestContext) -> Result<()> {
         println!(
             "----- remote layer for ten {} tli {} keys {}-{} lsn {}-{} ----",
-            self.tenantid,
-            self.timelineid,
-            self.key_range.start,
-            self.key_range.end,
-            self.lsn_range.start,
-            self.lsn_range.end
+            self.desc.tenant_id,
+            self.desc.timeline_id,
+            self.desc.key_range.start,
+            self.desc.key_range.end,
+            self.desc.lsn_range.start,
+            self.desc.lsn_range.end
         );
 
         Ok(())
     }
 
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_key_range(&self) -> Range<Key> {
+        self.layer_desc().key_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn get_lsn_range(&self) -> Range<Lsn> {
+        self.layer_desc().lsn_range.clone()
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
+    fn is_incremental(&self) -> bool {
+        self.layer_desc().is_incremental
+    }
+
+    /// Boilerplate to implement the Layer trait, always use layer_desc for persistent layers.
     fn short_id(&self) -> String {
-        self.filename().file_name()
+        self.layer_desc().short_id()
     }
 }
 
 impl PersistentLayer for RemoteLayer {
-    fn get_tenant_id(&self) -> TenantId {
-        self.tenantid
-    }
-
-    fn get_timeline_id(&self) -> TimelineId {
-        self.timelineid
-    }
-
-    fn filename(&self) -> LayerFileName {
-        if self.is_delta {
-            DeltaFileName {
-                key_range: self.key_range.clone(),
-                lsn_range: self.lsn_range.clone(),
-            }
-            .into()
-        } else {
-            ImageFileName {
-                key_range: self.key_range.clone(),
-                lsn: self.lsn_range.start,
-            }
-            .into()
-        }
+    fn layer_desc(&self) -> &PersistentLayerDesc {
+        &self.desc
     }
 
     fn local_path(&self) -> Option<PathBuf> {
@@ -176,7 +150,7 @@ impl PersistentLayer for RemoteLayer {
         let layer_file_name = self.filename().file_name();
         let lsn_range = self.get_lsn_range();
 
-        if self.is_delta {
+        if self.desc.is_delta {
             HistoricLayerInfo::Delta {
                 layer_file_name,
                 layer_file_size: self.layer_metadata.file_size(),
@@ -210,13 +184,13 @@ impl RemoteLayer {
         access_stats: LayerAccessStats,
     ) -> RemoteLayer {
         RemoteLayer {
-            tenantid,
-            timelineid,
-            key_range: fname.key_range.clone(),
-            lsn_range: fname.lsn_as_range(),
-            is_delta: false,
-            is_incremental: false,
-            file_name: fname.to_owned().into(),
+            desc: PersistentLayerDesc::new_img(
+                tenantid,
+                timelineid,
+                fname.key_range.clone(),
+                fname.lsn,
+                false,
+            ),
             layer_metadata: layer_metadata.clone(),
             ongoing_download: Arc::new(tokio::sync::Semaphore::new(1)),
             download_replacement_failure: std::sync::atomic::AtomicBool::default(),
@@ -232,13 +206,12 @@ impl RemoteLayer {
         access_stats: LayerAccessStats,
     ) -> RemoteLayer {
         RemoteLayer {
-            tenantid,
-            timelineid,
-            key_range: fname.key_range.clone(),
-            lsn_range: fname.lsn_range.clone(),
-            is_delta: true,
-            is_incremental: true,
-            file_name: fname.to_owned().into(),
+            desc: PersistentLayerDesc::new_delta(
+                tenantid,
+                timelineid,
+                fname.key_range.clone(),
+                fname.lsn_range.clone(),
+            ),
             layer_metadata: layer_metadata.clone(),
             ongoing_download: Arc::new(tokio::sync::Semaphore::new(1)),
             download_replacement_failure: std::sync::atomic::AtomicBool::default(),
@@ -256,15 +229,12 @@ impl RemoteLayer {
     where
         L: ?Sized + Layer,
     {
-        if self.is_delta {
-            let fname = DeltaFileName {
-                key_range: self.key_range.clone(),
-                lsn_range: self.lsn_range.clone(),
-            };
+        if self.desc.is_delta {
+            let fname = self.desc.delta_file_name();
             Arc::new(DeltaLayer::new(
                 conf,
-                self.timelineid,
-                self.tenantid,
+                self.desc.timeline_id,
+                self.desc.tenant_id,
                 &fname,
                 file_size,
                 self.access_stats.clone_for_residence_change(
@@ -273,14 +243,11 @@ impl RemoteLayer {
                 ),
             ))
         } else {
-            let fname = ImageFileName {
-                key_range: self.key_range.clone(),
-                lsn: self.lsn_range.start,
-            };
+            let fname = self.desc.image_file_name();
             Arc::new(ImageLayer::new(
                 conf,
-                self.timelineid,
-                self.tenantid,
+                self.desc.timeline_id,
+                self.desc.tenant_id,
                 &fname,
                 file_size,
                 self.access_stats.clone_for_residence_change(
diff --git a/pageserver/src/tenant/tasks.rs b/pageserver/src/tenant/tasks.rs
index 02aed11114..1bbc1b1c08 100644
--- a/pageserver/src/tenant/tasks.rs
+++ b/pageserver/src/tenant/tasks.rs
@@ -14,6 +14,10 @@ use tokio_util::sync::CancellationToken;
 use tracing::*;
 use utils::completion;
 
+/// Start per tenant background loops: compaction and gc.
+///
+/// `init_done` is an optional channel used during initial load to delay background task
+/// start. It is not used later.
 pub fn start_background_loops(tenant: &Arc<Tenant>, init_done: Option<&completion::Barrier>) {
     let tenant_id = tenant.tenant_id;
     task_mgr::spawn(
diff --git a/pageserver/src/tenant/timeline.rs b/pageserver/src/tenant/timeline.rs
index 36c4b0bcd4..fdaad58e16 100644
--- a/pageserver/src/tenant/timeline.rs
+++ b/pageserver/src/tenant/timeline.rs
@@ -57,6 +57,7 @@ use pageserver_api::reltag::RelTag;
 use postgres_connection::PgConnectionConfig;
 use postgres_ffi::to_pg_timestamp;
 use utils::{
+    completion,
     id::{TenantId, TimelineId},
     lsn::{AtomicLsn, Lsn, RecordLsn},
     seqwait::SeqWait,
@@ -525,7 +526,12 @@ impl Timeline {
             Some((cached_lsn, cached_img)) => {
                 match cached_lsn.cmp(&lsn) {
                     Ordering::Less => {} // there might be WAL between cached_lsn and lsn, we need to check
-                    Ordering::Equal => return Ok(cached_img), // exact LSN match, return the image
+                    Ordering::Equal => {
+                        self.metrics
+                            .materialized_page_cache_hit_upon_request_counter
+                            .inc();
+                        return Ok(cached_img); // exact LSN match, return the image
+                    }
                     Ordering::Greater => {
                         unreachable!("the returned lsn should never be after the requested lsn")
                     }
@@ -540,8 +546,10 @@ impl Timeline {
             img: cached_page_img,
         };
 
+        let timer = self.metrics.get_reconstruct_data_time_histo.start_timer();
         self.get_reconstruct_data(key, lsn, &mut reconstruct_state, ctx)
             .await?;
+        timer.stop_and_record();
 
         self.metrics
             .reconstruct_time_histo
@@ -921,10 +929,15 @@ impl Timeline {
         Ok(())
     }
 
-    pub fn activate(self: &Arc<Self>, broker_client: BrokerClientChannel, ctx: &RequestContext) {
+    pub fn activate(
+        self: &Arc<Self>,
+        broker_client: BrokerClientChannel,
+        init_done: Option<&completion::Barrier>,
+        ctx: &RequestContext,
+    ) {
         self.launch_wal_receiver(ctx, broker_client);
         self.set_state(TimelineState::Active);
-        self.launch_eviction_task();
+        self.launch_eviction_task(init_done);
     }
 
     pub fn set_state(&self, new_state: TimelineState) {
@@ -2261,6 +2274,9 @@ impl Timeline {
         let mut timeline_owned;
         let mut timeline = self;
 
+        let mut read_count =
+            scopeguard::guard(0, |cnt| self.metrics.read_num_fs_layers.observe(cnt as f64));
+
         // For debugging purposes, collect the path of layers that we traversed
         // through. It's included in the error message if we fail to find the key.
         let mut traversal_path = Vec::<TraversalPathItem>::new();
@@ -2395,6 +2411,7 @@ impl Timeline {
                                 Err(e) => return Err(PageReconstructError::from(e)),
                             };
                             cont_lsn = lsn_floor;
+                            // metrics: open_layer does not count as fs access, so we are not updating `read_count`
                             traversal_path.push((
                                 result,
                                 cont_lsn,
@@ -2421,6 +2438,7 @@ impl Timeline {
                                 Err(e) => return Err(PageReconstructError::from(e)),
                             };
                             cont_lsn = lsn_floor;
+                            // metrics: open_layer does not count as fs access, so we are not updating `read_count`
                             traversal_path.push((
                                 result,
                                 cont_lsn,
@@ -2455,6 +2473,7 @@ impl Timeline {
                                 Err(e) => return Err(PageReconstructError::from(e)),
                             };
                             cont_lsn = lsn_floor;
+                            *read_count += 1;
                             traversal_path.push((
                                 result,
                                 cont_lsn,
@@ -2520,7 +2539,7 @@ impl Timeline {
                     (DownloadBehavior::Error, false) => {
                         return Err(PageReconstructError::NeedsDownload(
                             TenantTimelineId::new(self.tenant_id, self.timeline_id),
-                            remote_layer.file_name.clone(),
+                            remote_layer.filename(),
                         ))
                     }
                 }
@@ -3053,6 +3072,7 @@ impl Timeline {
                     self.tenant_id,
                     &img_range,
                     lsn,
+                    false, // image layer always covers the full range
                 )?;
 
                 fail_point!("image-layer-writer-fail-before-finish", |_| {
@@ -3729,6 +3749,7 @@ impl Timeline {
         // Is the timeline being deleted?
         let state = *self.state.borrow();
         if state == TimelineState::Stopping {
+            // there's a global allowed_error for this
             anyhow::bail!("timeline is Stopping");
         }
 
@@ -4113,7 +4134,7 @@ impl Timeline {
                 // Does retries + exponential back-off internally.
                 // When this fails, don't layer further retry attempts here.
                 let result = remote_client
-                    .download_layer_file(&remote_layer.file_name, &remote_layer.layer_metadata)
+                    .download_layer_file(&remote_layer.filename(), &remote_layer.layer_metadata)
                     .await;
 
                 if let Ok(size) = &result {
diff --git a/pageserver/src/tenant/timeline/eviction_task.rs b/pageserver/src/tenant/timeline/eviction_task.rs
index 558600692e..7029d75d63 100644
--- a/pageserver/src/tenant/timeline/eviction_task.rs
+++ b/pageserver/src/tenant/timeline/eviction_task.rs
@@ -34,6 +34,8 @@ use crate::{
     },
 };
 
+use utils::completion;
+
 use super::Timeline;
 
 #[derive(Default)]
@@ -47,8 +49,9 @@ pub struct EvictionTaskTenantState {
 }
 
 impl Timeline {
-    pub(super) fn launch_eviction_task(self: &Arc<Self>) {
+    pub(super) fn launch_eviction_task(self: &Arc<Self>, init_done: Option<&completion::Barrier>) {
         let self_clone = Arc::clone(self);
+        let init_done = init_done.cloned();
         task_mgr::spawn(
             BACKGROUND_RUNTIME.handle(),
             TaskKind::Eviction,
@@ -57,6 +60,7 @@ impl Timeline {
             &format!("layer eviction for {}/{}", self.tenant_id, self.timeline_id),
             false,
             async move {
+                completion::Barrier::maybe_wait(init_done).await;
                 self_clone.eviction_task(task_mgr::shutdown_token()).await;
                 info!("eviction task finishing");
                 Ok(())
diff --git a/pageserver/src/tenant/timeline/walreceiver.rs b/pageserver/src/tenant/timeline/walreceiver.rs
index 7ebf3cf172..ccff735c3c 100644
--- a/pageserver/src/tenant/timeline/walreceiver.rs
+++ b/pageserver/src/tenant/timeline/walreceiver.rs
@@ -25,6 +25,7 @@ mod walreceiver_connection;
 
 use crate::context::{DownloadBehavior, RequestContext};
 use crate::task_mgr::{self, TaskKind, WALRECEIVER_RUNTIME};
+use crate::tenant::debug_assert_current_span_has_tenant_and_timeline_id;
 use crate::tenant::timeline::walreceiver::connection_manager::{
     connection_manager_loop_step, ConnectionManagerState,
 };
@@ -85,7 +86,8 @@ impl WalReceiver {
             &format!("walreceiver for timeline {tenant_id}/{timeline_id}"),
             false,
             async move {
-                info!("WAL receiver manager started, connecting to broker");
+                debug_assert_current_span_has_tenant_and_timeline_id();
+                debug!("WAL receiver manager started, connecting to broker");
                 let mut connection_manager_state = ConnectionManagerState::new(
                     timeline,
                     conf,
@@ -93,7 +95,7 @@ impl WalReceiver {
                 loop {
                     select! {
                         _ = task_mgr::shutdown_watcher() => {
-                            info!("WAL receiver shutdown requested, shutting down");
+                            trace!("WAL receiver shutdown requested, shutting down");
                             break;
                         },
                         loop_step_result = connection_manager_loop_step(
@@ -104,7 +106,7 @@ impl WalReceiver {
                         ) => match loop_step_result {
                             ControlFlow::Continue(()) => continue,
                             ControlFlow::Break(()) => {
-                                info!("Connection manager loop ended, shutting down");
+                                trace!("Connection manager loop ended, shutting down");
                                 break;
                             }
                         },
@@ -115,7 +117,7 @@ impl WalReceiver {
                 *loop_status.write().unwrap() = None;
                 Ok(())
             }
-            .instrument(info_span!(parent: None, "wal_connection_manager", tenant = %tenant_id, timeline = %timeline_id))
+            .instrument(info_span!(parent: None, "wal_connection_manager", tenant_id = %tenant_id, timeline_id = %timeline_id))
         );
 
         Self {
@@ -198,29 +200,19 @@ impl<E: Clone> TaskHandle<E> {
                 TaskEvent::End(match self.join_handle.as_mut() {
                     Some(jh) => {
                         if !jh.is_finished() {
-                            // Barring any implementation errors in this module, we can
-                            // only arrive here while the task that executes the future
-                            // passed to `Self::spawn()` is still execution. Cf the comment
-                            // in Self::spawn().
-                            //
-                            // This was logging at warning level in earlier versions, presumably
-                            // to leave some breadcrumbs in case we had an implementation
-                            // error that would would make us get stuck in `jh.await`.
-                            //
-                            // There hasn't been such a bug so far.
-                            // But in a busy system, e.g., during pageserver restart,
-                            // we arrive here often enough that the warning-level logs
-                            // became a distraction.
-                            // So, tone them down to info-level.
-                            //
-                            // XXX: rewrite this module to eliminate the race condition.
-                            info!("sender is dropped while join handle is still alive");
+                            // See: https://github.com/neondatabase/neon/issues/2885
+                            trace!("sender is dropped while join handle is still alive");
                         }
 
-                        let res = jh
-                            .await
-                            .map_err(|e| anyhow::anyhow!("Failed to join task: {e}"))
-                            .and_then(|x| x);
+                        let res = match jh.await {
+                            Ok(res) => res,
+                            Err(je) if je.is_cancelled() => unreachable!("not used"),
+                            Err(je) if je.is_panic() => {
+                                // already logged
+                                Ok(())
+                            }
+                            Err(je) => Err(anyhow::Error::new(je).context("join walreceiver task")),
+                        };
 
                         // For cancellation-safety, drop join_handle only after successful .await.
                         self.join_handle = None;
@@ -243,12 +235,12 @@ impl<E: Clone> TaskHandle<E> {
             match jh.await {
                 Ok(Ok(())) => debug!("Shutdown success"),
                 Ok(Err(e)) => error!("Shutdown task error: {e:?}"),
-                Err(join_error) => {
-                    if join_error.is_cancelled() {
-                        error!("Shutdown task was cancelled");
-                    } else {
-                        error!("Shutdown task join error: {join_error}")
-                    }
+                Err(je) if je.is_cancelled() => unreachable!("not used"),
+                Err(je) if je.is_panic() => {
+                    // already logged
+                }
+                Err(je) => {
+                    error!("Shutdown task join error: {je}")
                 }
             }
         }
diff --git a/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs b/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs
index 6b65e1fd42..e235fab425 100644
--- a/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs
+++ b/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs
@@ -18,7 +18,7 @@ use crate::metrics::{
     WALRECEIVER_CANDIDATES_REMOVED, WALRECEIVER_SWITCHES,
 };
 use crate::task_mgr::TaskKind;
-use crate::tenant::Timeline;
+use crate::tenant::{debug_assert_current_span_has_tenant_and_timeline_id, Timeline};
 use anyhow::Context;
 use chrono::{NaiveDateTime, Utc};
 use pageserver_api::models::TimelineState;
@@ -55,8 +55,11 @@ pub(super) async fn connection_manager_loop_step(
         .await
     {
         Ok(()) => {}
-        Err(_) => {
-            info!("Timeline dropped state updates sender before becoming active, stopping wal connection manager loop");
+        Err(new_state) => {
+            debug!(
+                ?new_state,
+                "state changed, stopping wal connection manager loop"
+            );
             return ControlFlow::Break(());
         }
     }
@@ -79,7 +82,7 @@ pub(super) async fn connection_manager_loop_step(
     // with other streams on this client (other connection managers). When
     // object goes out of scope, stream finishes in drop() automatically.
     let mut broker_subscription = subscribe_for_timeline_updates(broker_client, id).await;
-    info!("Subscribed for broker timeline updates");
+    debug!("Subscribed for broker timeline updates");
 
     loop {
         let time_until_next_retry = connection_manager_state.time_until_next_retry();
@@ -151,12 +154,12 @@ pub(super) async fn connection_manager_loop_step(
                                 // we're already active as walreceiver, no need to reactivate
                                 TimelineState::Active => continue,
                                 TimelineState::Broken | TimelineState::Stopping => {
-                                    info!("timeline entered terminal state {new_state:?}, stopping wal connection manager loop");
+                                    debug!("timeline entered terminal state {new_state:?}, stopping wal connection manager loop");
                                     return ControlFlow::Break(());
                                 }
                                 TimelineState::Loading => {
                                     warn!("timeline transitioned back to Loading state, that should not happen");
-                                    return ControlFlow::Continue(new_state);
+                                    return ControlFlow::Continue(());
                                 }
                             }
                         }
@@ -164,12 +167,11 @@ pub(super) async fn connection_manager_loop_step(
                     }
                 }
             } => match new_event {
-                ControlFlow::Continue(new_state) => {
-                    info!("observed timeline state change, new state is {new_state:?}");
+                ControlFlow::Continue(()) => {
                     return ControlFlow::Continue(());
                 }
                 ControlFlow::Break(()) => {
-                    info!("Timeline dropped state updates sender, stopping wal connection manager loop");
+                    debug!("Timeline is no longer active, stopping wal connection manager loop");
                     return ControlFlow::Break(());
                 }
             },
@@ -390,7 +392,6 @@ impl ConnectionManagerState {
 
         self.drop_old_connection(true).await;
 
-        let id = self.id;
         let node_id = new_sk.safekeeper_id;
         let connect_timeout = self.conf.wal_connect_timeout;
         let timeline = Arc::clone(&self.timeline);
@@ -398,9 +399,13 @@ impl ConnectionManagerState {
             TaskKind::WalReceiverConnectionHandler,
             DownloadBehavior::Download,
         );
+
+        let span = info_span!("connection", %node_id);
         let connection_handle = TaskHandle::spawn(move |events_sender, cancellation| {
             async move {
-                super::walreceiver_connection::handle_walreceiver_connection(
+                debug_assert_current_span_has_tenant_and_timeline_id();
+
+                let res = super::walreceiver_connection::handle_walreceiver_connection(
                     timeline,
                     new_sk.wal_source_connconf,
                     events_sender,
@@ -409,12 +414,23 @@ impl ConnectionManagerState {
                     ctx,
                     node_id,
                 )
-                .await
-                .context("walreceiver connection handling failure")
+                .await;
+
+                match res {
+                    Ok(()) => Ok(()),
+                    Err(e) => {
+                        use super::walreceiver_connection::ExpectedError;
+                        if e.is_expected() {
+                            info!("walreceiver connection handling ended: {e:#}");
+                            Ok(())
+                        } else {
+                            // give out an error to have task_mgr give it a really verbose logging
+                            Err(e).context("walreceiver connection handling failure")
+                        }
+                    }
+                }
             }
-            .instrument(
-                info_span!("walreceiver_connection", tenant_id = %id.tenant_id, timeline_id = %id.timeline_id, %node_id),
-            )
+            .instrument(span)
         });
 
         let now = Utc::now().naive_utc();
diff --git a/pageserver/src/tenant/timeline/walreceiver/walreceiver_connection.rs b/pageserver/src/tenant/timeline/walreceiver/walreceiver_connection.rs
index 1cbed3416c..41f6c63d40 100644
--- a/pageserver/src/tenant/timeline/walreceiver/walreceiver_connection.rs
+++ b/pageserver/src/tenant/timeline/walreceiver/walreceiver_connection.rs
@@ -21,16 +21,16 @@ use postgres_types::PgLsn;
 use tokio::{select, sync::watch, time};
 use tokio_postgres::{replication::ReplicationStream, Client};
 use tokio_util::sync::CancellationToken;
-use tracing::{debug, error, info, trace, warn};
+use tracing::{debug, error, info, trace, warn, Instrument};
 
 use super::TaskStateUpdate;
-use crate::metrics::LIVE_CONNECTIONS_COUNT;
-use crate::{context::RequestContext, metrics::WALRECEIVER_STARTED_CONNECTIONS};
 use crate::{
+    context::RequestContext,
+    metrics::{LIVE_CONNECTIONS_COUNT, WALRECEIVER_STARTED_CONNECTIONS},
     task_mgr,
     task_mgr::TaskKind,
     task_mgr::WALRECEIVER_RUNTIME,
-    tenant::{Timeline, WalReceiverInfo},
+    tenant::{debug_assert_current_span_has_tenant_and_timeline_id, Timeline, WalReceiverInfo},
     walingest::WalIngest,
     walrecord::DecodedWALRecord,
 };
@@ -81,13 +81,8 @@ pub(super) async fn handle_walreceiver_connection(
         config.application_name("pageserver");
         config.replication_mode(tokio_postgres::config::ReplicationMode::Physical);
         match time::timeout(connect_timeout, config.connect(postgres::NoTls)).await {
-            Ok(Ok(client_and_conn)) => client_and_conn,
-            Ok(Err(conn_err)) => {
-                let expected_error = ignore_expected_errors(conn_err)?;
-                info!("DB connection stream finished: {expected_error}");
-                return Ok(());
-            }
-            Err(_) => {
+            Ok(client_and_conn) => client_and_conn?,
+            Err(_elapsed) => {
                 // Timing out to connect to a safekeeper node could happen long time, due to
                 // many reasons that pageserver cannot control.
                 // Do not produce an error, but make it visible, that timeouts happen by logging the `event.
@@ -97,7 +92,7 @@ pub(super) async fn handle_walreceiver_connection(
         }
     };
 
-    info!("connected!");
+    debug!("connected!");
     let mut connection_status = WalConnectionStatus {
         is_connected: true,
         has_processed_wal: false,
@@ -127,20 +122,24 @@ pub(super) async fn handle_walreceiver_connection(
         "walreceiver connection",
         false,
         async move {
+            debug_assert_current_span_has_tenant_and_timeline_id();
+
             select! {
                 connection_result = connection => match connection_result {
-                    Ok(()) => info!("Walreceiver db connection closed"),
+                    Ok(()) => debug!("Walreceiver db connection closed"),
                     Err(connection_error) => {
-                        if let Err(e) = ignore_expected_errors(connection_error) {
-                            warn!("Connection aborted: {e:#}")
+                        if connection_error.is_expected() {
+                            // silence
+                        } else {
+                            warn!("Connection aborted: {connection_error:#}")
                         }
                     }
                 },
-                // Future: replace connection_cancellation with connection_ctx cancellation
-                _ = connection_cancellation.cancelled() => info!("Connection cancelled"),
+                _ = connection_cancellation.cancelled() => debug!("Connection cancelled"),
             }
             Ok(())
-        },
+        }
+        .instrument(tracing::info_span!("poller")),
     );
 
     // Immediately increment the gauge, then create a job to decrement it on task exit.
@@ -203,20 +202,13 @@ pub(super) async fn handle_walreceiver_connection(
     while let Some(replication_message) = {
         select! {
             _ = cancellation.cancelled() => {
-                info!("walreceiver interrupted");
+                debug!("walreceiver interrupted");
                 None
             }
             replication_message = physical_stream.next() => replication_message,
         }
     } {
-        let replication_message = match replication_message {
-            Ok(message) => message,
-            Err(replication_error) => {
-                let expected_error = ignore_expected_errors(replication_error)?;
-                info!("Replication stream finished: {expected_error}");
-                return Ok(());
-            }
-        };
+        let replication_message = replication_message?;
 
         let now = Utc::now().naive_utc();
         let last_rec_lsn_before_msg = last_rec_lsn;
@@ -261,8 +253,6 @@ pub(super) async fn handle_walreceiver_connection(
                     let mut decoded = DecodedWALRecord::default();
                     let mut modification = timeline.begin_modification(endlsn);
                     while let Some((lsn, recdata)) = waldecoder.poll_decode()? {
-                        // let _enter = info_span!("processing record", lsn = %lsn).entered();
-
                         // It is important to deal with the aligned records as lsn in getPage@LSN is
                         // aligned and can be several bytes bigger. Without this alignment we are
                         // at risk of hitting a deadlock.
@@ -421,31 +411,50 @@ async fn identify_system(client: &mut Client) -> anyhow::Result<IdentifySystem>
     }
 }
 
-/// We don't want to report connectivity problems as real errors towards connection manager because
-/// 1. they happen frequently enough to make server logs hard to read and
-/// 2. the connection manager can retry other safekeeper.
-///
-/// If this function returns `Ok(pg_error)`, it's such an error.
-/// The caller should log it at info level and then report to connection manager that we're done handling this connection.
-/// Connection manager will then handle reconnections.
-///
-/// If this function returns an `Err()`, the caller can bubble it up using `?`.
-/// The connection manager will log the error at ERROR level.
-fn ignore_expected_errors(pg_error: postgres::Error) -> anyhow::Result<postgres::Error> {
-    if pg_error.is_closed()
-        || pg_error
-            .source()
-            .and_then(|source| source.downcast_ref::<std::io::Error>())
-            .map(is_expected_io_error)
-            .unwrap_or(false)
-    {
-        return Ok(pg_error);
-    } else if let Some(db_error) = pg_error.as_db_error() {
-        if db_error.code() == &SqlState::SUCCESSFUL_COMPLETION
-            && db_error.message().contains("ending streaming")
-        {
-            return Ok(pg_error);
-        }
+/// Trait for avoid reporting walreceiver specific expected or "normal" or "ok" errors.
+pub(super) trait ExpectedError {
+    /// Test if this error is an ok error.
+    ///
+    /// We don't want to report connectivity problems as real errors towards connection manager because
+    /// 1. they happen frequently enough to make server logs hard to read and
+    /// 2. the connection manager can retry other safekeeper.
+    ///
+    /// If this function returns `true`, it's such an error.
+    /// The caller should log it at info level and then report to connection manager that we're done handling this connection.
+    /// Connection manager will then handle reconnections.
+    ///
+    /// If this function returns an `false` the error should be propagated and the connection manager
+    /// will log the error at ERROR level.
+    fn is_expected(&self) -> bool;
+}
+
+impl ExpectedError for postgres::Error {
+    fn is_expected(&self) -> bool {
+        self.is_closed()
+            || self
+                .source()
+                .and_then(|source| source.downcast_ref::<std::io::Error>())
+                .map(is_expected_io_error)
+                .unwrap_or(false)
+            || self
+                .as_db_error()
+                .filter(|db_error| {
+                    db_error.code() == &SqlState::SUCCESSFUL_COMPLETION
+                        && db_error.message().contains("ending streaming")
+                })
+                .is_some()
     }
-    Err(pg_error).context("connection error")
+}
+
+impl ExpectedError for anyhow::Error {
+    fn is_expected(&self) -> bool {
+        let head = self.downcast_ref::<postgres::Error>();
+
+        let tail = self
+            .chain()
+            .filter_map(|e| e.downcast_ref::<postgres::Error>());
+
+        // check if self or any of the chained/sourced errors are expected
+        head.into_iter().chain(tail).any(|e| e.is_expected())
+    }
 }
diff --git a/pgxn/hnsw/Makefile b/pgxn/hnsw/Makefile
new file mode 100644
index 0000000000..66436b5920
--- /dev/null
+++ b/pgxn/hnsw/Makefile
@@ -0,0 +1,26 @@
+EXTENSION = hnsw
+EXTVERSION = 0.1.0
+
+MODULE_big = hnsw
+DATA = $(wildcard *--*.sql)
+OBJS = hnsw.o hnswalg.o
+
+TESTS = $(wildcard test/sql/*.sql)
+REGRESS = $(patsubst test/sql/%.sql,%,$(TESTS))
+REGRESS_OPTS = --inputdir=test --load-extension=hnsw
+
+# For auto-vectorization:
+# - GCC (needs -ftree-vectorize OR -O3) - https://gcc.gnu.org/projects/tree-ssa/vectorization.html
+PG_CFLAGS += -O3
+PG_CXXFLAGS +=  -O3 -std=c++11
+PG_LDFLAGS += -lstdc++
+
+all: $(EXTENSION)--$(EXTVERSION).sql
+
+PG_CONFIG ?= pg_config
+PGXS := $(shell $(PG_CONFIG) --pgxs)
+include $(PGXS)
+
+dist:
+	mkdir -p dist
+	git archive --format zip --prefix=$(EXTENSION)-$(EXTVERSION)/ --output dist/$(EXTENSION)-$(EXTVERSION).zip master
diff --git a/pgxn/hnsw/README.md b/pgxn/hnsw/README.md
new file mode 100644
index 0000000000..bc9c8d571c
--- /dev/null
+++ b/pgxn/hnsw/README.md
@@ -0,0 +1,25 @@
+# Revisiting the Inverted Indices for Billion-Scale Approximate Nearest Neighbors
+
+This ANN extension of Postgres is based
+on [ivf-hnsw](https://github.com/dbaranchuk/ivf-hnsw.git) implementation of [HNSW](https://www.pinecone.io/learn/hnsw),
+the code for the current state-of-the-art billion-scale nearest neighbor search system presented in the paper:
+
+[Revisiting the Inverted Indices for Billion-Scale Approximate Nearest Neighbors](http://openaccess.thecvf.com/content_ECCV_2018/html/Dmitry_Baranchuk_Revisiting_the_Inverted_ECCV_2018_paper.html),
+<br>
+Dmitry Baranchuk, Artem Babenko, Yury Malkov
+
+# Postgres extension
+
+HNSW index is hold in memory (built on demand) and it's maxial size is limited
+by `maxelements` index parameter. Another required parameter is nubmer of dimensions (if it is not specified in column type).
+Optional parameter `ef` specifies number of neighbors which are considered during index construction and search (corresponds `efConstruction` and `efSearch` parameters
+described in the article).
+
+# Example of usage:
+
+```
+create extension hnsw;
+create table embeddings(id integer primary key, payload real[]);
+create index on embeddings using hnsw(payload) with (maxelements=1000000, dims=100, m=32);
+select id from embeddings order by payload <-> array[1.0, 2.0,...] limit 100;
+```
\ No newline at end of file
diff --git a/pgxn/hnsw/hnsw--0.1.0.sql b/pgxn/hnsw/hnsw--0.1.0.sql
new file mode 100644
index 0000000000..ebf424326d
--- /dev/null
+++ b/pgxn/hnsw/hnsw--0.1.0.sql
@@ -0,0 +1,29 @@
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "CREATE EXTENSION hnsw" to load this file. \quit
+
+-- functions
+
+CREATE FUNCTION l2_distance(real[], real[]) RETURNS real
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
+-- operators
+
+CREATE OPERATOR <-> (
+	LEFTARG = real[], RIGHTARG = real[], PROCEDURE = l2_distance,
+	COMMUTATOR = '<->'
+);
+
+-- access method
+
+CREATE FUNCTION hnsw_handler(internal) RETURNS index_am_handler
+	AS 'MODULE_PATHNAME' LANGUAGE C;
+
+CREATE ACCESS METHOD hnsw TYPE INDEX HANDLER hnsw_handler;
+
+COMMENT ON ACCESS METHOD hnsw IS 'hnsw index access method';
+
+-- opclasses
+
+CREATE OPERATOR CLASS knn_ops
+	DEFAULT FOR TYPE real[] USING hnsw AS
+	OPERATOR 1 <-> (real[], real[]) FOR ORDER BY float_ops;
diff --git a/pgxn/hnsw/hnsw.c b/pgxn/hnsw/hnsw.c
new file mode 100644
index 0000000000..434f4986f8
--- /dev/null
+++ b/pgxn/hnsw/hnsw.c
@@ -0,0 +1,551 @@
+#include "postgres.h"
+
+#include "access/amapi.h"
+#include "access/generic_xlog.h"
+#include "access/relation.h"
+#include "access/reloptions.h"
+#include "access/tableam.h"
+#include "catalog/index.h"
+#include "commands/vacuum.h"
+#include "nodes/execnodes.h"
+#include "storage/bufmgr.h"
+#include "utils/guc.h"
+#include "utils/selfuncs.h"
+
+#include <math.h>
+#include <float.h>
+
+#include "hnsw.h"
+
+PG_MODULE_MAGIC;
+
+typedef struct {
+	int32 vl_len_;		/* varlena header (do not touch directly!) */
+	int dims;
+	int maxelements;
+	int efConstruction;
+	int efSearch;
+	int M;
+} HnswOptions;
+
+static relopt_kind hnsw_relopt_kind;
+
+typedef struct {
+	HierarchicalNSW* hnsw;
+	size_t curr;
+	size_t n_results;
+	ItemPointer results;
+} HnswScanOpaqueData;
+
+typedef HnswScanOpaqueData* HnswScanOpaque;
+
+typedef struct {
+	Oid relid;
+	uint32 status;
+	HierarchicalNSW* hnsw;
+} HnswHashEntry;
+
+
+#define SH_PREFIX			 hnsw_index
+#define SH_ELEMENT_TYPE		 HnswHashEntry
+#define SH_KEY_TYPE			 Oid
+#define SH_KEY				 relid
+#define SH_STORE_HASH
+#define SH_GET_HASH(tb, a)	 ((a)->relid)
+#define SH_HASH_KEY(tb, key) (key)
+#define SH_EQUAL(tb, a, b)	((a) == (b))
+#define SH_SCOPE			static inline
+#define SH_DEFINE
+#define SH_DECLARE
+#include "lib/simplehash.h"
+
+#define INDEX_HASH_SIZE     11
+
+#define DEFAULT_EF_SEARCH   64
+
+PGDLLEXPORT void _PG_init(void);
+
+static hnsw_index_hash *hnsw_indexes;
+
+/*
+ * Initialize index options and variables
+ */
+void
+_PG_init(void)
+{
+	hnsw_relopt_kind = add_reloption_kind();
+	add_int_reloption(hnsw_relopt_kind, "dims", "Number of dimensions",
+					  0, 0, INT_MAX, AccessExclusiveLock);
+	add_int_reloption(hnsw_relopt_kind, "maxelements", "Maximal number of elements",
+					  0, 0, INT_MAX, AccessExclusiveLock);
+	add_int_reloption(hnsw_relopt_kind, "m", "Number of neighbors of each vertex",
+					  100, 0, INT_MAX, AccessExclusiveLock);
+	add_int_reloption(hnsw_relopt_kind, "efconstruction", "Number of inspected neighbors during index construction",
+					  16, 1, INT_MAX, AccessExclusiveLock);
+	add_int_reloption(hnsw_relopt_kind, "efsearch", "Number of inspected neighbors during index search",
+					  64, 1, INT_MAX, AccessExclusiveLock);
+	hnsw_indexes = hnsw_index_create(TopMemoryContext, INDEX_HASH_SIZE, NULL);
+}
+
+
+static void
+hnsw_build_callback(Relation index, ItemPointer tid, Datum *values,
+					bool *isnull, bool tupleIsAlive, void *state)
+{
+	HierarchicalNSW* hnsw = (HierarchicalNSW*) state;
+	ArrayType* array;
+	int n_items;
+	label_t label = 0;
+
+	/* Skip nulls */
+	if (isnull[0])
+		return;
+
+	array = DatumGetArrayTypeP(values[0]);
+	n_items = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+	if (n_items != hnsw_dimensions(hnsw))
+	{
+		elog(ERROR, "Wrong number of dimensions: %d instead of %d expected",
+			 n_items, hnsw_dimensions(hnsw));
+	}
+
+	memcpy(&label, tid, sizeof(*tid));
+	hnsw_add_point(hnsw, (coord_t*)ARR_DATA_PTR(array), label);
+}
+
+static void
+hnsw_populate(HierarchicalNSW* hnsw, Relation indexRel, Relation heapRel)
+{
+	IndexInfo* indexInfo = BuildIndexInfo(indexRel);
+	Assert(indexInfo->ii_NumIndexAttrs == 1);
+	table_index_build_scan(heapRel, indexRel, indexInfo,
+						   true, true, hnsw_build_callback, (void *) hnsw, NULL);
+}
+
+static HierarchicalNSW*
+hnsw_get_index(Relation indexRel, Relation heapRel)
+{
+	HierarchicalNSW* hnsw;
+	Oid indexoid = RelationGetRelid(indexRel);
+	HnswHashEntry* entry = hnsw_index_lookup(hnsw_indexes, indexoid);
+	if (entry == NULL)
+	{
+		size_t dims, maxelements;
+		size_t M;
+		size_t maxM;
+		size_t size_links_level0;
+		size_t size_data_per_element;
+		size_t data_size;
+		dsm_handle handle = indexoid << 1; /* make it even */
+		void* impl_private = NULL;
+		void* mapped_address = NULL;
+		Size  mapped_size = 0;
+		Size  shmem_size;
+		bool exists = true;
+		bool found;
+		HnswOptions *opts = (HnswOptions *) indexRel->rd_options;
+		if (opts == NULL || opts->maxelements == 0 || opts->dims == 0) {
+			elog(ERROR, "HNSW index requires 'maxelements' and 'dims' to be specified");
+		}
+		dims = opts->dims;
+		maxelements = opts->maxelements;
+		M = opts->M;
+		maxM = M * 2;
+		data_size = dims * sizeof(coord_t);
+		size_links_level0 = (maxM + 1) * sizeof(idx_t);
+		size_data_per_element = size_links_level0 + data_size + sizeof(label_t);
+		shmem_size =  hnsw_sizeof() + maxelements * size_data_per_element;
+
+		/* first try to attach to existed index */
+		if (!dsm_impl_op(DSM_OP_ATTACH, handle, 0, &impl_private,
+						 &mapped_address, &mapped_size, DEBUG1))
+		{
+			/* index doesn't exists: try to create it */
+			if (!dsm_impl_op(DSM_OP_CREATE, handle, shmem_size, &impl_private,
+							 &mapped_address, &mapped_size, DEBUG1))
+			{
+				/* We can do it under shared lock, so some other backend may
+				 * try to initialize index. If create is failed because index already
+				 * created by somebody else, then try to attach to it once again
+				 */
+				if (!dsm_impl_op(DSM_OP_ATTACH, handle, 0, &impl_private,
+								 &mapped_address, &mapped_size, ERROR))
+				{
+					return NULL;
+				}
+			}
+			else
+			{
+				exists = false;
+			}
+		}
+		Assert(mapped_size == shmem_size);
+		hnsw = (HierarchicalNSW*)mapped_address;
+
+		if (!exists)
+		{
+			hnsw_init(hnsw, dims, maxelements, M, maxM, opts->efConstruction);
+			hnsw_populate(hnsw, indexRel, heapRel);
+		}
+		entry = hnsw_index_insert(hnsw_indexes, indexoid, &found);
+		Assert(!found);
+		entry->hnsw = hnsw;
+	}
+	else
+	{
+		hnsw = entry->hnsw;
+	}
+	return hnsw;
+}
+
+/*
+ * Start or restart an index scan
+ */
+static IndexScanDesc
+hnsw_beginscan(Relation index, int nkeys, int norderbys)
+{
+	IndexScanDesc scan = RelationGetIndexScan(index, nkeys, norderbys);
+	HnswScanOpaque so = (HnswScanOpaque) palloc(sizeof(HnswScanOpaqueData));
+	Relation heap = relation_open(index->rd_index->indrelid, NoLock);
+	so->hnsw = hnsw_get_index(index, heap);
+	relation_close(heap, NoLock);
+	so->curr = 0;
+	so->n_results = 0;
+	so->results = NULL;
+	scan->opaque = so;
+	return scan;
+}
+
+/*
+ * Start or restart an index scan
+ */
+static void
+hnsw_rescan(IndexScanDesc scan, ScanKey keys, int nkeys, ScanKey orderbys, int norderbys)
+{
+	HnswScanOpaque so = (HnswScanOpaque) scan->opaque;
+	if (so->results)
+	{
+		pfree(so->results);
+		so->results = NULL;
+	}
+	so->curr = 0;
+	if (orderbys && scan->numberOfOrderBys > 0)
+		memmove(scan->orderByData, orderbys, scan->numberOfOrderBys * sizeof(ScanKeyData));
+}
+
+/*
+ * Fetch the next tuple in the given scan
+ */
+static bool
+hnsw_gettuple(IndexScanDesc scan, ScanDirection dir)
+{
+	HnswScanOpaque so = (HnswScanOpaque) scan->opaque;
+
+	/*
+	 * Index can be used to scan backward, but Postgres doesn't support
+	 * backward scan on operators
+	 */
+	Assert(ScanDirectionIsForward(dir));
+
+	if (so->curr == 0)
+	{
+		Datum		value;
+		ArrayType*	array;
+		int         n_items;
+		size_t      n_results;
+		label_t*    results;
+		HnswOptions *opts = (HnswOptions *) scan->indexRelation->rd_options;
+		size_t      efSearch = opts ? opts->efSearch : DEFAULT_EF_SEARCH;
+
+		/* Safety check */
+		if (scan->orderByData == NULL)
+			elog(ERROR, "cannot scan HNSW index without order");
+
+		/* No items will match if null */
+		if (scan->orderByData->sk_flags & SK_ISNULL)
+			return false;
+
+		value = scan->orderByData->sk_argument;
+		array = DatumGetArrayTypeP(value);
+		n_items = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+		if (n_items != hnsw_dimensions(so->hnsw))
+		{
+			elog(ERROR, "Wrong number of dimensions: %d instead of %d expected",
+				 n_items, hnsw_dimensions(so->hnsw));
+		}
+
+		if (!hnsw_search(so->hnsw, (coord_t*)ARR_DATA_PTR(array), efSearch, &n_results, &results))
+			elog(ERROR, "HNSW index search failed");
+		so->results = (ItemPointer)palloc(n_results*sizeof(ItemPointerData));
+		so->n_results = n_results;
+		for (size_t i = 0; i < n_results; i++)
+		{
+			memcpy(&so->results[i], &results[i], sizeof(so->results[i]));
+		}
+		free(results);
+	}
+	if (so->curr >= so->n_results)
+	{
+		return false;
+	}
+	else
+	{
+		scan->xs_heaptid = so->results[so->curr++];
+		scan->xs_recheckorderby = false;
+		return true;
+	}
+}
+
+/*
+ * End a scan and release resources
+ */
+static void
+hnsw_endscan(IndexScanDesc scan)
+{
+	HnswScanOpaque so = (HnswScanOpaque) scan->opaque;
+	if (so->results)
+		pfree(so->results);
+	pfree(so);
+	scan->opaque = NULL;
+}
+
+
+/*
+ * Estimate the cost of an index scan
+ */
+static void
+hnsw_costestimate(PlannerInfo *root, IndexPath *path, double loop_count,
+				 Cost *indexStartupCost, Cost *indexTotalCost,
+				 Selectivity *indexSelectivity, double *indexCorrelation
+				 ,double *indexPages
+)
+{
+	GenericCosts costs;
+
+	/* Never use index without order */
+	if (path->indexorderbys == NULL)
+	{
+		*indexStartupCost = DBL_MAX;
+		*indexTotalCost = DBL_MAX;
+		*indexSelectivity = 0;
+		*indexCorrelation = 0;
+		*indexPages = 0;
+		return;
+	}
+
+	MemSet(&costs, 0, sizeof(costs));
+
+	genericcostestimate(root, path, loop_count, &costs);
+
+	/* Startup cost and total cost are same */
+	*indexStartupCost = costs.indexTotalCost;
+	*indexTotalCost = costs.indexTotalCost;
+	*indexSelectivity = costs.indexSelectivity;
+	*indexCorrelation = costs.indexCorrelation;
+	*indexPages = costs.numIndexPages;
+}
+
+/*
+ * Parse and validate the reloptions
+ */
+static bytea *
+hnsw_options(Datum reloptions, bool validate)
+{
+	static const relopt_parse_elt tab[] = {
+		{"dims", RELOPT_TYPE_INT, offsetof(HnswOptions, dims)},
+		{"maxelements", RELOPT_TYPE_INT, offsetof(HnswOptions, maxelements)},
+		{"efconstruction", RELOPT_TYPE_INT, offsetof(HnswOptions, efConstruction)},
+		{"efsearch", RELOPT_TYPE_INT, offsetof(HnswOptions, efSearch)},
+		{"m", RELOPT_TYPE_INT, offsetof(HnswOptions, M)}
+	};
+
+	return (bytea *) build_reloptions(reloptions, validate,
+									  hnsw_relopt_kind,
+									  sizeof(HnswOptions),
+									  tab, lengthof(tab));
+}
+
+/*
+ * Validate catalog entries for the specified operator class
+ */
+static bool
+hnsw_validate(Oid opclassoid)
+{
+	return true;
+}
+
+/*
+ * Build the index for a logged table
+ */
+static IndexBuildResult *
+hnsw_build(Relation heap, Relation index, IndexInfo *indexInfo)
+{
+	HierarchicalNSW* hnsw = hnsw_get_index(index, heap);
+	IndexBuildResult* result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
+	result->heap_tuples = result->index_tuples = hnsw_count(hnsw);
+
+	return result;
+}
+
+/*
+ * Insert a tuple into the index
+ */
+static bool
+hnsw_insert(Relation index, Datum *values, bool *isnull, ItemPointer heap_tid,
+			  Relation heap, IndexUniqueCheck checkUnique,
+			  bool indexUnchanged,
+			  IndexInfo *indexInfo)
+{
+	HierarchicalNSW* hnsw = hnsw_get_index(index, heap);
+	Datum value;
+	ArrayType* array;
+	int n_items;
+	label_t label = 0;
+
+	/* Skip nulls */
+	if (isnull[0])
+		return false;
+
+	/* Detoast value */
+	value = PointerGetDatum(PG_DETOAST_DATUM(values[0]));
+	array = DatumGetArrayTypeP(value);
+	n_items = ArrayGetNItems(ARR_NDIM(array), ARR_DIMS(array));
+	if (n_items != hnsw_dimensions(hnsw))
+	{
+		elog(ERROR, "Wrong number of dimensions: %d instead of %d expected",
+			 n_items, hnsw_dimensions(hnsw));
+	}
+	memcpy(&label, heap_tid, sizeof(*heap_tid));
+	if (!hnsw_add_point(hnsw, (coord_t*)ARR_DATA_PTR(array), label))
+		elog(ERROR, "HNSW index insert failed");
+	return true;
+}
+
+/*
+ * Build the index for an unlogged table
+ */
+static void
+hnsw_buildempty(Relation index)
+{
+	/* index will be constructed on dema nd when accessed */
+}
+
+/*
+ * Clean up after a VACUUM operation
+ */
+static IndexBulkDeleteResult *
+hnsw_vacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
+{
+	Relation	rel = info->index;
+
+	if (stats == NULL)
+		return NULL;
+
+	stats->num_pages = RelationGetNumberOfBlocks(rel);
+
+	return stats;
+}
+
+/*
+ * Bulk delete tuples from the index
+ */
+static IndexBulkDeleteResult *
+hnsw_bulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
+				IndexBulkDeleteCallback callback, void *callback_state)
+{
+	if (stats == NULL)
+		stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
+	return stats;
+}
+
+/*
+ * Define index handler
+ *
+ * See https://www.postgresql.org/docs/current/index-api.html
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(hnsw_handler);
+Datum
+hnsw_handler(PG_FUNCTION_ARGS)
+{
+	IndexAmRoutine *amroutine = makeNode(IndexAmRoutine);
+
+	amroutine->amstrategies = 0;
+	amroutine->amsupport = 0;
+	amroutine->amoptsprocnum = 0;
+	amroutine->amcanorder = false;
+	amroutine->amcanorderbyop = true;
+	amroutine->amcanbackward = false;	/* can change direction mid-scan */
+	amroutine->amcanunique = false;
+	amroutine->amcanmulticol = false;
+	amroutine->amoptionalkey = true;
+	amroutine->amsearcharray = false;
+	amroutine->amsearchnulls = false;
+	amroutine->amstorage = false;
+	amroutine->amclusterable = false;
+	amroutine->ampredlocks = false;
+	amroutine->amcanparallel = false;
+	amroutine->amcaninclude = false;
+	amroutine->amusemaintenanceworkmem = false; /* not used during VACUUM */
+	amroutine->amparallelvacuumoptions = VACUUM_OPTION_PARALLEL_BULKDEL;
+	amroutine->amkeytype = InvalidOid;
+
+	/* Interface functions */
+	amroutine->ambuild = hnsw_build;
+	amroutine->ambuildempty = hnsw_buildempty;
+	amroutine->aminsert = hnsw_insert;
+	amroutine->ambulkdelete = hnsw_bulkdelete;
+	amroutine->amvacuumcleanup = hnsw_vacuumcleanup;
+	amroutine->amcanreturn = NULL;	/* tuple not included in heapsort */
+	amroutine->amcostestimate = hnsw_costestimate;
+	amroutine->amoptions = hnsw_options;
+	amroutine->amproperty = NULL;	/* TODO AMPROP_DISTANCE_ORDERABLE */
+	amroutine->ambuildphasename = NULL;
+	amroutine->amvalidate = hnsw_validate;
+	amroutine->amadjustmembers = NULL;
+	amroutine->ambeginscan = hnsw_beginscan;
+	amroutine->amrescan = hnsw_rescan;
+	amroutine->amgettuple = hnsw_gettuple;
+	amroutine->amgetbitmap = NULL;
+	amroutine->amendscan = hnsw_endscan;
+	amroutine->ammarkpos = NULL;
+	amroutine->amrestrpos = NULL;
+
+	/* Interface functions to support parallel index scans */
+	amroutine->amestimateparallelscan = NULL;
+	amroutine->aminitparallelscan = NULL;
+	amroutine->amparallelrescan = NULL;
+
+	PG_RETURN_POINTER(amroutine);
+}
+
+/*
+ * Get the L2 distance between vectors
+ */
+PGDLLEXPORT PG_FUNCTION_INFO_V1(l2_distance);
+Datum
+l2_distance(PG_FUNCTION_ARGS)
+{
+	ArrayType  *a = PG_GETARG_ARRAYTYPE_P(0);
+	ArrayType  *b = PG_GETARG_ARRAYTYPE_P(1);
+	int         a_dim = ArrayGetNItems(ARR_NDIM(a), ARR_DIMS(a));
+	int         b_dim = ArrayGetNItems(ARR_NDIM(b), ARR_DIMS(b));
+	dist_t 		distance = 0.0;
+	dist_t		diff;
+	coord_t	   *ax = (coord_t*)ARR_DATA_PTR(a);
+	coord_t	   *bx = (coord_t*)ARR_DATA_PTR(b);
+
+	if (a_dim != b_dim)
+	{
+		ereport(ERROR,
+				(errcode(ERRCODE_DATA_EXCEPTION),
+				 errmsg("different array dimensions %d and %d", a_dim, b_dim)));
+	}
+
+	for (int i = 0; i < a_dim; i++)
+	{
+		diff = ax[i] - bx[i];
+		distance += diff * diff;
+	}
+
+	PG_RETURN_FLOAT4((dist_t)sqrt(distance));
+}
diff --git a/pgxn/hnsw/hnsw.control b/pgxn/hnsw/hnsw.control
new file mode 100644
index 0000000000..b292b96026
--- /dev/null
+++ b/pgxn/hnsw/hnsw.control
@@ -0,0 +1,5 @@
+comment = 'hNsw index'
+default_version = '0.1.0'
+module_pathname = '$libdir/hnsw'
+relocatable = true
+trusted = true
diff --git a/pgxn/hnsw/hnsw.h b/pgxn/hnsw/hnsw.h
new file mode 100644
index 0000000000..d4065ab8fe
--- /dev/null
+++ b/pgxn/hnsw/hnsw.h
@@ -0,0 +1,15 @@
+#pragma once
+
+typedef float    coord_t;
+typedef float    dist_t;
+typedef uint32_t idx_t;
+typedef uint64_t label_t;
+
+typedef struct HierarchicalNSW HierarchicalNSW;
+
+bool hnsw_search(HierarchicalNSW* hnsw, const coord_t *point, size_t efSearch, size_t* n_results, label_t** results);
+bool hnsw_add_point(HierarchicalNSW* hnsw, const coord_t *point, label_t label);
+void hnsw_init(HierarchicalNSW* hnsw, size_t dim, size_t maxelements, size_t M, size_t maxM, size_t efConstruction);
+int  hnsw_dimensions(HierarchicalNSW* hnsw);
+size_t hnsw_count(HierarchicalNSW* hnsw);
+size_t hnsw_sizeof(void);
diff --git a/pgxn/hnsw/hnswalg.cpp b/pgxn/hnsw/hnswalg.cpp
new file mode 100644
index 0000000000..f6de3b8314
--- /dev/null
+++ b/pgxn/hnsw/hnswalg.cpp
@@ -0,0 +1,379 @@
+#include "hnswalg.h"
+
+#if defined(__GNUC__)
+#define PORTABLE_ALIGN32 __attribute__((aligned(32)))
+#define PREFETCH(addr,hint) __builtin_prefetch(addr, 0, hint)
+#else
+#define PORTABLE_ALIGN32 __declspec(align(32))
+#define PREFETCH(addr,hint)
+#endif
+
+HierarchicalNSW::HierarchicalNSW(size_t dim_, size_t maxelements_, size_t M_, size_t maxM_, size_t efConstruction_)
+{
+    dim = dim_;
+    data_size = dim * sizeof(coord_t);
+
+    efConstruction = efConstruction_;
+
+    maxelements = maxelements_;
+    M = M_;
+    maxM = maxM_;
+    size_links_level0 = (maxM + 1) * sizeof(idx_t);
+    size_data_per_element = size_links_level0 + data_size  + sizeof(label_t);
+    offset_data = size_links_level0;
+	offset_label = offset_data + data_size;
+
+    enterpoint_node = 0;
+    cur_element_count = 0;
+#ifdef __x86_64__
+    use_avx2 = __builtin_cpu_supports("avx2");
+#endif
+}
+
+std::priority_queue<std::pair<dist_t, idx_t>> HierarchicalNSW::searchBaseLayer(const coord_t *point, size_t ef)
+{
+	std::vector<uint32_t> visited;
+	visited.resize((cur_element_count + 31) >> 5);
+
+    std::priority_queue<std::pair<dist_t, idx_t >> topResults;
+    std::priority_queue<std::pair<dist_t, idx_t >> candidateSet;
+
+    dist_t dist = fstdistfunc(point, getDataByInternalId(enterpoint_node));
+
+    topResults.emplace(dist, enterpoint_node);
+    candidateSet.emplace(-dist, enterpoint_node);
+    visited[enterpoint_node >> 5] = 1 << (enterpoint_node & 31);
+    dist_t lowerBound = dist;
+
+    while (!candidateSet.empty())
+    {
+        std::pair<dist_t, idx_t> curr_el_pair = candidateSet.top();
+        if (-curr_el_pair.first > lowerBound)
+            break;
+
+        candidateSet.pop();
+        idx_t curNodeNum = curr_el_pair.second;
+
+        idx_t* data = get_linklist0(curNodeNum);
+        size_t size = *data++;
+
+        PREFETCH(getDataByInternalId(*data), 0);
+
+        for (size_t j = 0; j < size; ++j) {
+            size_t tnum = *(data + j);
+
+            PREFETCH(getDataByInternalId(*(data + j + 1)), 0);
+
+            if (!(visited[tnum >> 5] & (1 << (tnum & 31)))) {
+				visited[tnum >> 5] |= 1 << (tnum & 31);
+
+                dist = fstdistfunc(point, getDataByInternalId(tnum));
+
+                if (topResults.top().first > dist || topResults.size() < ef) {
+                    candidateSet.emplace(-dist, tnum);
+
+                    PREFETCH(get_linklist0(candidateSet.top().second), 0);
+                    topResults.emplace(dist, tnum);
+
+                    if (topResults.size() > ef)
+                        topResults.pop();
+
+                    lowerBound = topResults.top().first;
+                }
+            }
+        }
+    }
+    return topResults;
+}
+
+
+void HierarchicalNSW::getNeighborsByHeuristic(std::priority_queue<std::pair<dist_t, idx_t>> &topResults, size_t NN)
+{
+    if (topResults.size() < NN)
+        return;
+
+    std::priority_queue<std::pair<dist_t, idx_t>> resultSet;
+    std::vector<std::pair<dist_t, idx_t>> returnlist;
+
+    while (topResults.size() > 0) {
+        resultSet.emplace(-topResults.top().first, topResults.top().second);
+        topResults.pop();
+    }
+
+    while (resultSet.size()) {
+        if (returnlist.size() >= NN)
+            break;
+        std::pair<dist_t, idx_t> curen = resultSet.top();
+        dist_t dist_to_query = -curen.first;
+        resultSet.pop();
+        bool good = true;
+        for (std::pair<dist_t, idx_t> curen2 : returnlist) {
+            dist_t curdist = fstdistfunc(getDataByInternalId(curen2.second),
+                                         getDataByInternalId(curen.second));
+            if (curdist < dist_to_query) {
+                good = false;
+                break;
+            }
+        }
+        if (good) returnlist.push_back(curen);
+    }
+    for (std::pair<dist_t, idx_t> elem : returnlist)
+        topResults.emplace(-elem.first, elem.second);
+}
+
+void HierarchicalNSW::mutuallyConnectNewElement(const coord_t *point, idx_t cur_c,
+                               std::priority_queue<std::pair<dist_t, idx_t>> topResults)
+{
+    getNeighborsByHeuristic(topResults, M);
+
+    std::vector<idx_t> res;
+    res.reserve(M);
+    while (topResults.size() > 0) {
+        res.push_back(topResults.top().second);
+        topResults.pop();
+    }
+    {
+        idx_t* data = get_linklist0(cur_c);
+        if (*data)
+            throw std::runtime_error("Should be blank");
+
+        *data++ = res.size();
+
+        for (size_t idx = 0; idx < res.size(); idx++) {
+            if (data[idx])
+                throw std::runtime_error("Should be blank");
+            data[idx] = res[idx];
+        }
+    }
+    for (size_t idx = 0; idx < res.size(); idx++) {
+        if (res[idx] == cur_c)
+            throw std::runtime_error("Connection to the same element");
+
+        size_t resMmax = maxM;
+        idx_t *ll_other = get_linklist0(res[idx]);
+        idx_t sz_link_list_other = *ll_other;
+
+        if (sz_link_list_other > resMmax || sz_link_list_other < 0)
+            throw std::runtime_error("Bad sz_link_list_other");
+
+        if (sz_link_list_other < resMmax) {
+            idx_t *data = ll_other + 1;
+            data[sz_link_list_other] = cur_c;
+            *ll_other = sz_link_list_other + 1;
+        } else {
+            // finding the "weakest" element to replace it with the new one
+            idx_t *data = ll_other + 1;
+            dist_t d_max = fstdistfunc(getDataByInternalId(cur_c), getDataByInternalId(res[idx]));
+            // Heuristic:
+            std::priority_queue<std::pair<dist_t, idx_t>> candidates;
+            candidates.emplace(d_max, cur_c);
+
+            for (size_t j = 0; j < sz_link_list_other; j++)
+                candidates.emplace(fstdistfunc(getDataByInternalId(data[j]), getDataByInternalId(res[idx])), data[j]);
+
+            getNeighborsByHeuristic(candidates, resMmax);
+
+            size_t indx = 0;
+            while (!candidates.empty()) {
+                data[indx] = candidates.top().second;
+                candidates.pop();
+                indx++;
+            }
+            *ll_other = indx;
+        }
+    }
+}
+
+void HierarchicalNSW::addPoint(const coord_t *point, label_t label)
+{
+    if (cur_element_count >= maxelements) {
+        throw std::runtime_error("The number of elements exceeds the specified limit");
+    }
+    idx_t cur_c = cur_element_count++;
+    memset((char *) get_linklist0(cur_c), 0, size_data_per_element);
+    memcpy(getDataByInternalId(cur_c), point, data_size);
+    memcpy(getExternalLabel(cur_c), &label, sizeof label);
+
+    // Do nothing for the first element
+    if (cur_c != 0) {
+        std::priority_queue <std::pair<dist_t, idx_t>> topResults = searchBaseLayer(point, efConstruction);
+        mutuallyConnectNewElement(point, cur_c, topResults);
+    }
+};
+
+std::priority_queue<std::pair<dist_t, label_t>> HierarchicalNSW::searchKnn(const coord_t *query, size_t k)
+{
+	std::priority_queue<std::pair<dist_t, label_t>> topResults;
+	auto topCandidates = searchBaseLayer(query, k);
+    while (topCandidates.size() > k) {
+        topCandidates.pop();
+	}
+	while (!topCandidates.empty()) {
+		std::pair<dist_t, idx_t> rez = topCandidates.top();
+		label_t label;
+		memcpy(&label, getExternalLabel(rez.second), sizeof(label));
+		topResults.push(std::pair<dist_t, label_t>(rez.first, label));
+		topCandidates.pop();
+	}
+
+    return topResults;
+};
+
+dist_t fstdistfunc_scalar(const coord_t *x, const coord_t *y, size_t n)
+{
+    dist_t 	distance = 0.0;
+
+    for (size_t i = 0; i < n; i++)
+    {
+        dist_t diff = x[i] - y[i];
+        distance += diff * diff;
+    }
+    return distance;
+
+}
+
+#ifdef __x86_64__
+#include <immintrin.h>
+
+__attribute__((target("avx2")))
+dist_t fstdistfunc_avx2(const coord_t *x, const coord_t *y, size_t n)
+{
+    const size_t TmpResSz = sizeof(__m256) / sizeof(float);
+    float PORTABLE_ALIGN32 TmpRes[TmpResSz];
+    size_t qty16 = n / 16;
+    const float *pEnd1 = x + (qty16 * 16);
+    __m256 diff, v1, v2;
+    __m256 sum = _mm256_set1_ps(0);
+
+    while (x < pEnd1) {
+        v1 = _mm256_loadu_ps(x);
+        x += 8;
+        v2 = _mm256_loadu_ps(y);
+        y += 8;
+        diff = _mm256_sub_ps(v1, v2);
+        sum = _mm256_add_ps(sum, _mm256_mul_ps(diff, diff));
+
+        v1 = _mm256_loadu_ps(x);
+        x += 8;
+        v2 = _mm256_loadu_ps(y);
+        y += 8;
+        diff = _mm256_sub_ps(v1, v2);
+        sum = _mm256_add_ps(sum, _mm256_mul_ps(diff, diff));
+    }
+    _mm256_store_ps(TmpRes, sum);
+    float res = TmpRes[0] + TmpRes[1] + TmpRes[2] + TmpRes[3] + TmpRes[4] + TmpRes[5] + TmpRes[6] + TmpRes[7];
+    return (res);
+}
+
+dist_t fstdistfunc_sse(const coord_t *x, const coord_t *y, size_t n)
+{
+    const size_t TmpResSz = sizeof(__m128) / sizeof(float);
+    float PORTABLE_ALIGN32 TmpRes[TmpResSz];
+    size_t qty16 = n / 16;
+    const float *pEnd1 = x + (qty16 * 16);
+
+    __m128 diff, v1, v2;
+    __m128 sum = _mm_set1_ps(0);
+
+    while (x < pEnd1) {
+        v1 = _mm_loadu_ps(x);
+        x += 4;
+        v2 = _mm_loadu_ps(y);
+        y += 4;
+        diff = _mm_sub_ps(v1, v2);
+        sum = _mm_add_ps(sum, _mm_mul_ps(diff, diff));
+
+        v1 = _mm_loadu_ps(x);
+        x += 4;
+        v2 = _mm_loadu_ps(y);
+        y += 4;
+        diff = _mm_sub_ps(v1, v2);
+        sum = _mm_add_ps(sum, _mm_mul_ps(diff, diff));
+
+        v1 = _mm_loadu_ps(x);
+        x += 4;
+        v2 = _mm_loadu_ps(y);
+        y += 4;
+        diff = _mm_sub_ps(v1, v2);
+        sum = _mm_add_ps(sum, _mm_mul_ps(diff, diff));
+
+        v1 = _mm_loadu_ps(x);
+        x += 4;
+        v2 = _mm_loadu_ps(y);
+        y += 4;
+        diff = _mm_sub_ps(v1, v2);
+        sum = _mm_add_ps(sum, _mm_mul_ps(diff, diff));
+    }
+    _mm_store_ps(TmpRes, sum);
+    float res = TmpRes[0] + TmpRes[1] + TmpRes[2] + TmpRes[3];
+    return res;
+}
+#endif
+
+dist_t HierarchicalNSW::fstdistfunc(const coord_t *x, const coord_t *y)
+{
+#ifndef __x86_64__
+    return fstdistfunc_scalar(x, y, dim);
+#else
+    if(use_avx2)
+        return fstdistfunc_avx2(x, y, dim);
+
+    return fstdistfunc_sse(x, y, dim);
+#endif
+}
+
+bool hnsw_search(HierarchicalNSW* hnsw, const coord_t *point, size_t efSearch, size_t* n_results, label_t** results)
+{
+	try
+	{
+		auto result = hnsw->searchKnn(point, efSearch);
+		size_t nResults = result.size();
+		*results = (label_t*)malloc(nResults*sizeof(label_t));
+		for (size_t i = nResults; i-- != 0;)
+		{
+			(*results)[i] = result.top().second;
+			result.pop();
+		}
+		*n_results = nResults;
+		return true;
+	}
+	catch (std::exception& x)
+	{
+		return false;
+	}
+}
+
+bool hnsw_add_point(HierarchicalNSW* hnsw, const coord_t *point, label_t label)
+{
+	try
+	{
+		hnsw->addPoint(point, label);
+		return true;
+	}
+	catch (std::exception& x)
+	{
+		fprintf(stderr, "Catch %s\n", x.what());
+		return false;
+	}
+}
+
+void hnsw_init(HierarchicalNSW* hnsw, size_t dims, size_t maxelements, size_t M, size_t maxM, size_t efConstruction)
+{
+	new ((void*)hnsw) HierarchicalNSW(dims, maxelements, M, maxM, efConstruction);
+}
+
+
+int hnsw_dimensions(HierarchicalNSW* hnsw)
+{
+	return (int)hnsw->dim;
+}
+
+size_t hnsw_count(HierarchicalNSW* hnsw)
+{
+	return hnsw->cur_element_count;
+}
+
+size_t hnsw_sizeof(void)
+{
+	return sizeof(HierarchicalNSW);
+}
diff --git a/pgxn/hnsw/hnswalg.h b/pgxn/hnsw/hnswalg.h
new file mode 100644
index 0000000000..f38aeac362
--- /dev/null
+++ b/pgxn/hnsw/hnswalg.h
@@ -0,0 +1,69 @@
+#pragma once
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <unordered_map>
+#include <unordered_set>
+#include <map>
+#include <cmath>
+#include <queue>
+#include <stdexcept>
+
+extern "C" {
+#include "hnsw.h"
+}
+
+struct HierarchicalNSW
+{
+	size_t maxelements;
+	size_t cur_element_count;
+
+	idx_t  enterpoint_node;
+
+	size_t dim;
+	size_t data_size;
+	size_t offset_data;
+	size_t offset_label;
+	size_t size_data_per_element;
+	size_t M;
+	size_t maxM;
+	size_t size_links_level0;
+	size_t efConstruction;
+
+#ifdef __x86_64__
+	bool	use_avx2;
+#endif
+
+	char   data_level0_memory[0]; // varying size
+
+  public:
+	HierarchicalNSW(size_t dim, size_t maxelements, size_t M, size_t maxM, size_t efConstruction);
+	~HierarchicalNSW();
+
+
+	inline coord_t *getDataByInternalId(idx_t internal_id) const {
+		return (coord_t *)&data_level0_memory[internal_id * size_data_per_element + offset_data];
+	}
+
+	inline idx_t *get_linklist0(idx_t internal_id) const {
+		return (idx_t*)&data_level0_memory[internal_id * size_data_per_element];
+	}
+
+	inline label_t *getExternalLabel(idx_t internal_id) const {
+		return (label_t *)&data_level0_memory[internal_id * size_data_per_element + offset_label];
+	}
+
+	std::priority_queue<std::pair<dist_t, idx_t>> searchBaseLayer(const coord_t *x, size_t ef);
+
+	void getNeighborsByHeuristic(std::priority_queue<std::pair<dist_t, idx_t>> &topResults, size_t NN);
+
+	void mutuallyConnectNewElement(const coord_t *x, idx_t id, std::priority_queue<std::pair<dist_t, idx_t>> topResults);
+
+	void addPoint(const coord_t *point, label_t label);
+
+	std::priority_queue<std::pair<dist_t, label_t>> searchKnn(const coord_t *query_data, size_t k);
+
+	dist_t fstdistfunc(const coord_t *x, const coord_t *y);
+};
diff --git a/pgxn/hnsw/test/expected/knn.out b/pgxn/hnsw/test/expected/knn.out
new file mode 100644
index 0000000000..a1cee4525e
--- /dev/null
+++ b/pgxn/hnsw/test/expected/knn.out
@@ -0,0 +1,28 @@
+SET enable_seqscan = off;
+CREATE TABLE t (val real[]);
+INSERT INTO t (val) VALUES ('{0,0,0}'), ('{1,2,3}'), ('{1,1,1}'), (NULL);
+CREATE INDEX ON t USING hnsw (val) WITH (maxelements = 10, dims=3, m=3);
+INSERT INTO t (val) VALUES (array[1,2,4]);
+explain SELECT * FROM t ORDER BY val <-> array[3,3,3];
+                             QUERY PLAN                             
+--------------------------------------------------------------------
+ Index Scan using t_val_idx on t  (cost=4.02..8.06 rows=3 width=36)
+   Order By: (val <-> '{3,3,3}'::real[])
+(2 rows)
+
+SELECT * FROM t ORDER BY val <-> array[3,3,3];
+   val   
+---------
+ {1,2,3}
+ {1,2,4}
+ {1,1,1}
+ {0,0,0}
+(4 rows)
+
+SELECT COUNT(*) FROM t;
+ count 
+-------
+     5
+(1 row)
+
+DROP TABLE t;
diff --git a/pgxn/hnsw/test/sql/knn.sql b/pgxn/hnsw/test/sql/knn.sql
new file mode 100644
index 0000000000..0635bda4a2
--- /dev/null
+++ b/pgxn/hnsw/test/sql/knn.sql
@@ -0,0 +1,13 @@
+SET enable_seqscan = off;
+
+CREATE TABLE t (val real[]);
+INSERT INTO t (val) VALUES ('{0,0,0}'), ('{1,2,3}'), ('{1,1,1}'), (NULL);
+CREATE INDEX ON t USING hnsw (val) WITH (maxelements = 10, dims=3, m=3);
+
+INSERT INTO t (val) VALUES (array[1,2,4]);
+
+explain SELECT * FROM t ORDER BY val <-> array[3,3,3];
+SELECT * FROM t ORDER BY val <-> array[3,3,3];
+SELECT COUNT(*) FROM t;
+
+DROP TABLE t;
diff --git a/proxy/src/bin/pg_sni_router.rs b/proxy/src/bin/pg_sni_router.rs
index bba2d51caf..a5f50cc7c1 100644
--- a/proxy/src/bin/pg_sni_router.rs
+++ b/proxy/src/bin/pg_sni_router.rs
@@ -17,7 +17,7 @@ use tokio::io::{AsyncRead, AsyncWrite};
 use tokio_util::sync::CancellationToken;
 use utils::{project_git_version, sentry_init::init_sentry};
 
-use tracing::{error, info, warn};
+use tracing::{error, info, warn, Instrument};
 
 project_git_version!(GIT_VERSION);
 
@@ -141,7 +141,6 @@ async fn task_main(
         tokio::select! {
             accept_result = listener.accept() => {
                 let (socket, peer_addr) = accept_result?;
-                info!("accepted postgres client connection from {peer_addr}");
 
                 let session_id = uuid::Uuid::new_v4();
                 let tls_config = Arc::clone(&tls_config);
@@ -149,18 +148,18 @@ async fn task_main(
 
                 connections.spawn(
                     async move {
-                        info!("spawned a task for {peer_addr}");
-
                         socket
                             .set_nodelay(true)
                             .context("failed to set socket option")?;
 
-                        handle_client(dest_suffix, tls_config, session_id, socket).await
+                        info!(%peer_addr, "serving");
+                        handle_client(dest_suffix, tls_config, socket).await
                     }
                     .unwrap_or_else(|e| {
                         // Acknowledge that the task has finished with an error.
                         error!("per-client task finished with an error: {e:#}");
-                    }),
+                    })
+                    .instrument(tracing::info_span!("handle_client", ?session_id))
                 );
             }
             _ = cancellation_token.cancelled() => {
@@ -192,7 +191,6 @@ async fn ssl_handshake<S: AsyncRead + AsyncWrite + Unpin>(
     let mut stream = PqStream::new(Stream::from_raw(raw_stream));
 
     let msg = stream.read_startup_packet().await?;
-    info!("received {msg:?}");
     use pq_proto::FeStartupPacket::*;
 
     match msg {
@@ -215,15 +213,19 @@ async fn ssl_handshake<S: AsyncRead + AsyncWrite + Unpin>(
             }
             Ok(raw.upgrade(tls_config).await?)
         }
-        _ => stream.throw_error_str(ERR_INSECURE_CONNECTION).await?,
+        unexpected => {
+            info!(
+                ?unexpected,
+                "unexpected startup packet, rejecting connection"
+            );
+            stream.throw_error_str(ERR_INSECURE_CONNECTION).await?
+        }
     }
 }
 
-#[tracing::instrument(fields(session_id = ?session_id), skip_all)]
 async fn handle_client(
     dest_suffix: Arc<String>,
     tls_config: Arc<rustls::ServerConfig>,
-    session_id: uuid::Uuid,
     stream: impl AsyncRead + AsyncWrite + Unpin,
 ) -> anyhow::Result<()> {
     let tls_stream = ssl_handshake(stream, tls_config).await?;
diff --git a/proxy/src/console.rs b/proxy/src/console.rs
index 1f3ef99555..0e5eaaf845 100644
--- a/proxy/src/console.rs
+++ b/proxy/src/console.rs
@@ -1,5 +1,5 @@
-///! Various stuff for dealing with the Neon Console.
-///! Later we might move some API wrappers here.
+//! Various stuff for dealing with the Neon Console.
+//! Later we might move some API wrappers here.
 
 /// Payloads used in the console's APIs.
 pub mod messages;
diff --git a/proxy/src/proxy/tests.rs b/proxy/src/proxy/tests.rs
index 60acb588dc..3373c49676 100644
--- a/proxy/src/proxy/tests.rs
+++ b/proxy/src/proxy/tests.rs
@@ -1,4 +1,4 @@
-///! A group of high-level tests for connection establishing logic and auth.
+//! A group of high-level tests for connection establishing logic and auth.
 use super::*;
 use crate::{auth, sasl, scram};
 use async_trait::async_trait;
diff --git a/test_runner/fixtures/metrics.py b/test_runner/fixtures/metrics.py
index 0e958ddd06..b4c237cfa6 100644
--- a/test_runner/fixtures/metrics.py
+++ b/test_runner/fixtures/metrics.py
@@ -65,12 +65,19 @@ PAGESERVER_PER_TENANT_METRICS: Tuple[str, ...] = (
     "pageserver_getpage_reconstruct_seconds_bucket",
     "pageserver_getpage_reconstruct_seconds_count",
     "pageserver_getpage_reconstruct_seconds_sum",
+    "pageserver_getpage_get_reconstruct_data_seconds_bucket",
+    "pageserver_getpage_get_reconstruct_data_seconds_count",
+    "pageserver_getpage_get_reconstruct_data_seconds_sum",
     "pageserver_io_operations_bytes_total",
     "pageserver_io_operations_seconds_bucket",
     "pageserver_io_operations_seconds_count",
     "pageserver_io_operations_seconds_sum",
     "pageserver_last_record_lsn",
     "pageserver_materialized_cache_hits_total",
+    "pageserver_materialized_cache_hits_direct_total",
+    "pageserver_read_num_fs_layers_bucket",
+    "pageserver_read_num_fs_layers_count",
+    "pageserver_read_num_fs_layers_sum",
     "pageserver_smgr_query_seconds_bucket",
     "pageserver_smgr_query_seconds_count",
     "pageserver_smgr_query_seconds_sum",
diff --git a/test_runner/fixtures/neon_fixtures.py b/test_runner/fixtures/neon_fixtures.py
index 1007cb11b5..e23ed12878 100644
--- a/test_runner/fixtures/neon_fixtures.py
+++ b/test_runner/fixtures/neon_fixtures.py
@@ -629,7 +629,7 @@ class NeonEnvBuilder:
         assert self.env is not None, "environment is not already initialized, call init() first"
         self.env.start()
 
-    def init_start(self) -> NeonEnv:
+    def init_start(self, initial_tenant_conf: Optional[Dict[str, str]] = None) -> NeonEnv:
         env = self.init_configs()
         self.start()
 
@@ -638,7 +638,9 @@ class NeonEnvBuilder:
         log.info(
             f"Services started, creating initial tenant {env.initial_tenant} and its initial timeline"
         )
-        initial_tenant, initial_timeline = env.neon_cli.create_tenant(tenant_id=env.initial_tenant)
+        initial_tenant, initial_timeline = env.neon_cli.create_tenant(
+            tenant_id=env.initial_tenant, conf=initial_tenant_conf
+        )
         env.initial_timeline = initial_timeline
         log.info(f"Initial timeline {initial_tenant}/{initial_timeline} created successfully")
 
@@ -1583,13 +1585,10 @@ class NeonPageserver(PgProtocol):
             ".*serving compute connection task.*exited with error: Postgres connection error.*",
             ".*serving compute connection task.*exited with error: Connection reset by peer.*",
             ".*serving compute connection task.*exited with error: Postgres query error.*",
-            ".*Connection aborted: connection error: error communicating with the server: Broken pipe.*",
-            ".*Connection aborted: connection error: error communicating with the server: Transport endpoint is not connected.*",
-            ".*Connection aborted: connection error: error communicating with the server: Connection reset by peer.*",
             # FIXME: replication patch for tokio_postgres regards  any but CopyDone/CopyData message in CopyBoth stream as unexpected
-            ".*Connection aborted: connection error: unexpected message from server*",
+            ".*Connection aborted: unexpected message from server*",
             ".*kill_and_wait_impl.*: wait successful.*",
-            ".*Replication stream finished: db error:.*ending streaming to Some*",
+            ".*: db error:.*ending streaming to Some.*",
             ".*query handler for 'pagestream.*failed: Broken pipe.*",  # pageserver notices compute shut down
             ".*query handler for 'pagestream.*failed: Connection reset by peer.*",  # pageserver notices compute shut down
             # safekeeper connection can fail with this, in the window between timeline creation
@@ -1606,13 +1605,12 @@ class NeonPageserver(PgProtocol):
             ".*manual_gc.*is_shutdown_requested\\(\\) called in an unexpected task or thread.*",
             ".*tenant_list: timeline is not found in remote index while it is present in the tenants registry.*",
             ".*Removing intermediate uninit mark file.*",
-            # FIXME: known race condition in TaskHandle: https://github.com/neondatabase/neon/issues/2885
-            ".*sender is dropped while join handle is still alive.*",
             # Tenant::delete_timeline() can cause any of the four following errors.
             # FIXME: we shouldn't be considering it an error: https://github.com/neondatabase/neon/issues/2946
             ".*could not flush frozen layer.*queue is in state Stopped",  # when schedule layer upload fails because queued got closed before compaction got killed
             ".*wait for layer upload ops to complete.*",  # .*Caused by:.*wait_completion aborted because upload queue was stopped
             ".*gc_loop.*Gc failed, retrying in.*timeline is Stopping",  # When gc checks timeline state after acquiring layer_removal_cs
+            ".*gc_loop.*Gc failed, retrying in.*: Cannot run GC iteration on inactive tenant",  # Tenant::gc precondition
             ".*compaction_loop.*Compaction failed, retrying in.*timeline is Stopping",  # When compaction checks timeline state after acquiring layer_removal_cs
             ".*query handler for 'pagestream.*failed: Timeline .* was not found",  # postgres reconnects while timeline_delete doesn't hold the tenant's timelines.lock()
             ".*query handler for 'pagestream.*failed: Timeline .* is not active",  # timeline delete in progress
diff --git a/test_runner/regress/test_attach_tenant_config.py b/test_runner/regress/test_attach_tenant_config.py
index 6261ec28db..4df5ae18d6 100644
--- a/test_runner/regress/test_attach_tenant_config.py
+++ b/test_runner/regress/test_attach_tenant_config.py
@@ -20,6 +20,11 @@ def positive_env(neon_env_builder: NeonEnvBuilder) -> NeonEnv:
         test_name="test_attach_tenant_config",
     )
     env = neon_env_builder.init_start()
+
+    # eviction might be the first one after an attach to access the layers
+    env.pageserver.allowed_errors.append(
+        ".*unexpectedly on-demand downloading remote layer remote.* for task kind Eviction"
+    )
     assert isinstance(env.remote_storage, LocalFsStorage)
     return env
 
diff --git a/test_runner/regress/test_ondemand_download.py b/test_runner/regress/test_ondemand_download.py
index 1414b4ed8e..c26ec76172 100644
--- a/test_runner/regress/test_ondemand_download.py
+++ b/test_runner/regress/test_ondemand_download.py
@@ -58,11 +58,8 @@ def test_ondemand_download_large_rel(
     )
 
     ##### First start, insert secret data and upload it to the remote storage
-    env = neon_env_builder.init_start()
-
-    # Override defaults, to create more layers
-    tenant, _ = env.neon_cli.create_tenant(
-        conf={
+    env = neon_env_builder.init_start(
+        initial_tenant_conf={
             # disable background GC
             "gc_period": "0s",
             "gc_horizon": f"{10 * 1024 ** 3}",  # 10 GB
@@ -75,7 +72,6 @@ def test_ondemand_download_large_rel(
             "compaction_period": "0s",
         }
     )
-    env.initial_tenant = tenant
 
     endpoint = env.endpoints.create_start("main")
 
diff --git a/test_runner/regress/test_pageserver_restarts_under_workload.py b/test_runner/regress/test_pageserver_restarts_under_workload.py
index bc3f3f2be4..fc93dcffbb 100644
--- a/test_runner/regress/test_pageserver_restarts_under_workload.py
+++ b/test_runner/regress/test_pageserver_restarts_under_workload.py
@@ -17,12 +17,6 @@ def test_pageserver_restarts_under_worload(neon_simple_env: NeonEnv, pg_bin: PgB
     n_restarts = 10
     scale = 10
 
-    # the background task may complete the init task delay after finding an
-    # active tenant, but shutdown starts right before Tenant::gc_iteration
-    env.pageserver.allowed_errors.append(
-        r".*Gc failed, retrying in \S+: Cannot run GC iteration on inactive tenant"
-    )
-
     def run_pgbench(connstr: str):
         log.info(f"Start a pgbench workload on pg {connstr}")
         pg_bin.run_capture(["pgbench", "-i", f"-s{scale}", connstr])
diff --git a/test_runner/regress/test_sni_router.py b/test_runner/regress/test_sni_router.py
index f3aa429c49..9b78e8287e 100644
--- a/test_runner/regress/test_sni_router.py
+++ b/test_runner/regress/test_sni_router.py
@@ -37,6 +37,7 @@ class PgSniRouter(PgProtocol):
         destination: str,
         tls_cert: Path,
         tls_key: Path,
+        test_output_dir: Path,
     ):
         # Must use a hostname rather than IP here, for SNI to work
         host = "localhost"
@@ -49,6 +50,7 @@ class PgSniRouter(PgProtocol):
         self.tls_cert = tls_cert
         self.tls_key = tls_key
         self._popen: Optional[subprocess.Popen[bytes]] = None
+        self.test_output_dir = test_output_dir
 
     def start(self) -> "PgSniRouter":
         assert self._popen is None
@@ -60,8 +62,12 @@ class PgSniRouter(PgProtocol):
             *["--destination", self.destination],
         ]
 
-        self._popen = subprocess.Popen(args)
+        router_log_path = self.test_output_dir / "pg_sni_router.log"
+        router_log = open(router_log_path, "w")
+
+        self._popen = subprocess.Popen(args, stderr=router_log)
         self._wait_until_ready()
+        log.info(f"pg_sni_router started, log file: {router_log_path}")
         return self
 
     @backoff.on_exception(backoff.expo, OSError, max_time=10)
@@ -121,6 +127,7 @@ def test_pg_sni_router(
         destination="localtest.me",
         tls_cert=test_output_dir / "router.crt",
         tls_key=test_output_dir / "router.key",
+        test_output_dir=test_output_dir,
     ) as router:
         router.start()
 
diff --git a/test_runner/regress/test_timeline_delete.py b/test_runner/regress/test_timeline_delete.py
index 99bf400207..1e15a8e7cb 100644
--- a/test_runner/regress/test_timeline_delete.py
+++ b/test_runner/regress/test_timeline_delete.py
@@ -437,12 +437,22 @@ def test_delete_timeline_client_hangup(neon_env_builder: NeonEnvBuilder):
 
     wait_until(50, 0.1, got_hangup_log_message)
 
-    # ok, retry without failpoint, it should succeed
+    # check that the timeline is still present
+    ps_http.timeline_detail(env.initial_tenant, child_timeline_id)
+
+    # ok, disable the failpoint to let the deletion finish
     ps_http.configure_failpoints((failpoint_name, "off"))
 
-    # this should succeed
-    ps_http.timeline_delete(env.initial_tenant, child_timeline_id, timeout=2)
-    # the second call will try to transition the timeline into Stopping state, but it's already in that state
-    env.pageserver.allowed_errors.append(
-        f".*{child_timeline_id}.*Ignoring new state, equal to the existing one: Stopping"
-    )
+    def first_request_finished():
+        message = f".*DELETE.*{child_timeline_id}.*Cancelled request finished"
+        assert env.pageserver.log_contains(message)
+
+    wait_until(50, 0.1, first_request_finished)
+
+    # check that the timeline is gone
+    notfound_message = f"Timeline {env.initial_tenant}/{child_timeline_id} was not found"
+    env.pageserver.allowed_errors.append(".*" + notfound_message)
+    with pytest.raises(PageserverApiException, match=notfound_message) as exc:
+        ps_http.timeline_detail(env.initial_tenant, child_timeline_id)
+
+    assert exc.value.status_code == 404