Refactor common parts of handle_client and handle_ws_client to function.

There was a lot of duplicated code.

The resulting shared function now uses two tracing spans, one for
establishing the connections, and a separate span for forwarding the
traffic after that. This makes for nicer traces in the future, because
you can dig into how long the startup phase takes, and where the time
is spent.

.config/hakari.toml

@@ -4,7 +4,7 @@
 hakari-package = "workspace_hack"
 
 # Format for `workspace-hack = ...` lines in other Cargo.tomls. Requires cargo-hakari 0.9.8 or above.
-dep-format-version = "2"
+dep-format-version = "3"
 
 # Setting workspace.resolver = "2" in the root Cargo.toml is HIGHLY recommended.
 # Hakari works much better with the new feature resolver.

.github/actions/run-python-test-set/action.yml

@@ -123,8 +123,8 @@ runs:
           exit 1
         fi
         if [[ "${{ inputs.run_in_parallel }}" == "true" ]]; then
-          # -n4 uses four processes to run tests via pytest-xdist
-          EXTRA_PARAMS="-n4 $EXTRA_PARAMS"
+          # -n16 uses sixteen processes to run tests via pytest-xdist
+          EXTRA_PARAMS="-n16 $EXTRA_PARAMS"
 
           # --dist=loadgroup points tests marked with @pytest.mark.xdist_group
           # to the same worker to make @pytest.mark.order work with xdist

.github/ansible/deploy.yaml

@@ -117,7 +117,8 @@
       shell:
         cmd: |
           INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
-          curl -sfS -d '{"version": {{ current_version }} }' -X PATCH {{ console_mgmt_base_url }}/api/v1/pageservers/$INSTANCE_ID
+          curl -sfS -H "Authorization: Bearer {{ CONSOLE_API_TOKEN }}" {{ console_mgmt_base_url }}/management/api/v2/pageservers/$INSTANCE_ID | jq '.version = {{ current_version }}' > /tmp/new_version
+          curl -sfS -H "Authorization: Bearer {{ CONSOLE_API_TOKEN }}" -X POST -d@/tmp/new_version {{ console_mgmt_base_url }}/management/api/v2/pageservers
       tags:
       - pageserver
 
@@ -186,6 +187,7 @@
       shell:
         cmd: |
           INSTANCE_ID=$(curl -s http://169.254.169.254/latest/meta-data/instance-id)
-          curl -sfS -d '{"version": {{ current_version }} }' -X PATCH {{ console_mgmt_base_url }}/api/v1/safekeepers/$INSTANCE_ID
+          curl -sfS -H "Authorization: Bearer {{ CONSOLE_API_TOKEN }}" {{ console_mgmt_base_url }}/management/api/v2/safekeepers/$INSTANCE_ID | jq '.version = {{ current_version }}' > /tmp/new_version
+          curl -sfS -H "Authorization: Bearer {{ CONSOLE_API_TOKEN }}" -X POST -d@/tmp/new_version {{ console_mgmt_base_url }}/management/api/v2/safekeepers
       tags:
       - safekeeper

.github/ansible/prod.ap-southeast-1.hosts.yaml

@@ -6,6 +6,8 @@ storage:
     broker_endpoint: http://storage-broker-lb.epsilon.ap-southeast-1.internal.aws.neon.tech:50051
     pageserver_config_stub:
       pg_distrib_dir: /usr/local
+      metric_collection_endpoint: http://console-release.local/billing/api/v1/usage_events
+      metric_collection_interval: 10min
       remote_storage:
         bucket_name: "{{ bucket_name }}"
         bucket_region: "{{ bucket_region }}"

.github/ansible/prod.eu-central-1.hosts.yaml

@@ -6,6 +6,8 @@ storage:
     broker_endpoint: http://storage-broker-lb.gamma.eu-central-1.internal.aws.neon.tech:50051
     pageserver_config_stub:
       pg_distrib_dir: /usr/local
+      metric_collection_endpoint: http://console-release.local/billing/api/v1/usage_events
+      metric_collection_interval: 10min
       remote_storage:
         bucket_name: "{{ bucket_name }}"
         bucket_region: "{{ bucket_region }}"

.github/ansible/prod.us-east-2.hosts.yaml

@@ -6,6 +6,8 @@ storage:
     broker_endpoint: http://storage-broker-lb.delta.us-east-2.internal.aws.neon.tech:50051
     pageserver_config_stub:
       pg_distrib_dir: /usr/local
+      metric_collection_endpoint: http://console-release.local/billing/api/v1/usage_events
+      metric_collection_interval: 10min
       remote_storage:
         bucket_name: "{{ bucket_name }}"
         bucket_region: "{{ bucket_region }}"
@@ -34,4 +36,4 @@ storage:
           ansible_host:  i-06d113fb73bfddeb0
         safekeeper-2.us-east-2.aws.neon.tech:
           ansible_host:  i-09f66c8e04afff2e8
-          
+

.github/ansible/prod.us-west-2.hosts.yaml

@@ -6,6 +6,8 @@ storage:
     broker_endpoint: http://storage-broker-lb.eta.us-west-2.internal.aws.neon.tech:50051
     pageserver_config_stub:
       pg_distrib_dir: /usr/local
+      metric_collection_endpoint: http://console-release.local/billing/api/v1/usage_events
+      metric_collection_interval: 10min
       remote_storage:
         bucket_name: "{{ bucket_name }}"
         bucket_region: "{{ bucket_region }}"

.github/ansible/production.hosts.yaml

@@ -7,6 +7,8 @@ storage:
     broker_endpoint: http://storage-broker.prod.local:50051
     pageserver_config_stub:
       pg_distrib_dir: /usr/local
+      metric_collection_endpoint: http://console-release.local/billing/api/v1/usage_events
+      metric_collection_interval: 10min
       remote_storage:
         bucket_name: "{{ bucket_name }}"
         bucket_region: "{{ bucket_region }}"

.github/ansible/staging.eu-west-1.hosts.yaml

@@ -18,7 +18,7 @@ storage:
     ansible_aws_ssm_region: eu-west-1
     ansible_aws_ssm_bucket_name: neon-dev-storage-eu-west-1
     console_region_id: aws-eu-west-1
-    sentry_environment: development
+    sentry_environment: staging
 
   children:
     pageservers:

.github/ansible/staging.us-east-2.hosts.yaml

@@ -18,7 +18,7 @@ storage:
     ansible_aws_ssm_region: us-east-2
     ansible_aws_ssm_bucket_name: neon-staging-storage-us-east-2
     console_region_id: aws-us-east-2
-    sentry_environment: development
+    sentry_environment: staging
 
   children:
     pageservers:
@@ -29,6 +29,8 @@ storage:
           ansible_host: i-0565a8b4008aa3f40
         pageserver-2.us-east-2.aws.neon.build:
           ansible_host: i-01e31cdf7e970586a
+        pageserver-3.us-east-2.aws.neon.build:
+          ansible_host: i-0602a0291365ef7cc
 
     safekeepers:
       hosts:

.github/helm-values/dev-eu-west-1-zeta.neon-proxy-scram.yaml

@@ -8,8 +8,10 @@ settings:
   authBackend: "console"
   authEndpoint: "http://console-staging.local/management/api/v2"
   domain: "*.eu-west-1.aws.neon.build"
-  sentryEnvironment: "development"
+  sentryEnvironment: "staging"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-staging.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "1min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/dev-eu-west-1-zeta.neon-storage-broker.yaml

@@ -49,4 +49,4 @@ extraManifests:
           - "{{ .Release.Namespace }}"
 
 settings:
-  sentryEnvironment: "development"
+  sentryEnvironment: "staging"

.github/helm-values/dev-us-east-2-beta.neon-proxy-link.yaml

@@ -8,7 +8,10 @@ settings:
   authBackend: "link"
   authEndpoint: "https://console.stage.neon.tech/authenticate_proxy_request/"
   uri: "https://console.stage.neon.tech/psql_session/"
-  sentryEnvironment: "development"
+  domain: "pg.neon.build"
+  sentryEnvironment: "staging"
+  metricCollectionEndpoint: "http://console-staging.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "1min"
 
 # -- Additional labels for neon-proxy-link pods
 podLabels:

.github/helm-values/dev-us-east-2-beta.neon-proxy-scram-legacy.yaml

@@ -8,8 +8,10 @@ settings:
   authBackend: "console"
   authEndpoint: "http://console-staging.local/management/api/v2"
   domain: "*.cloud.stage.neon.tech"
-  sentryEnvironment: "development"
+  sentryEnvironment: "staging"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-staging.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "1min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/dev-us-east-2-beta.neon-proxy-scram.yaml

@@ -8,8 +8,10 @@ settings:
   authBackend: "console"
   authEndpoint: "http://console-staging.local/management/api/v2"
   domain: "*.us-east-2.aws.neon.build"
-  sentryEnvironment: "development"
+  sentryEnvironment: "staging"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-staging.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "1min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/dev-us-east-2-beta.neon-storage-broker.yaml

@@ -49,4 +49,4 @@ extraManifests:
           - "{{ .Release.Namespace }}"
 
 settings:
-  sentryEnvironment: "development"
+  sentryEnvironment: "staging"

.github/helm-values/prod-ap-southeast-1-epsilon.neon-proxy-scram.yaml

@@ -10,6 +10,8 @@ settings:
   domain: "*.ap-southeast-1.aws.neon.tech"
   sentryEnvironment: "production"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-release.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "10min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/prod-eu-central-1-gamma.neon-proxy-scram.yaml

@@ -10,6 +10,8 @@ settings:
   domain: "*.eu-central-1.aws.neon.tech"
   sentryEnvironment: "production"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-release.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "10min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/prod-us-east-2-delta.neon-proxy-link.yaml

@@ -0,0 +1,59 @@
+# Helm chart values for neon-proxy-link.
+# This is a YAML-formatted file.
+
+image:
+  repository: neondatabase/neon
+
+settings:
+  authBackend: "link"
+  authEndpoint: "https://console.neon.tech/authenticate_proxy_request/"
+  uri: "https://console.neon.tech/psql_session/"
+  domain: "pg.neon.tech"
+  sentryEnvironment: "production"
+
+# -- Additional labels for zenith-proxy pods
+podLabels:
+  zenith_service: proxy
+  zenith_env: production
+  zenith_region: us-east-2
+  zenith_region_slug: us-east-2
+
+service:
+  type: LoadBalancer
+  annotations:
+    service.beta.kubernetes.io/aws-load-balancer-type: external
+    service.beta.kubernetes.io/aws-load-balancer-nlb-target-type: ip
+    service.beta.kubernetes.io/aws-load-balancer-scheme: internal
+    external-dns.alpha.kubernetes.io/hostname: neon-proxy-link-mgmt.delta.us-east-2.aws.neon.tech
+
+exposedService:
+  annotations:
+    service.beta.kubernetes.io/aws-load-balancer-type: external
+    service.beta.kubernetes.io/aws-load-balancer-nlb-target-type: ip
+    service.beta.kubernetes.io/aws-load-balancer-scheme: internet-facing
+    external-dns.alpha.kubernetes.io/hostname: neon-proxy-link.delta.us-east-2.aws.neon.tech
+
+extraManifests:
+  - apiVersion: operator.victoriametrics.com/v1beta1
+    kind: VMServiceScrape
+    metadata:
+      name: "{{ include \"neon-proxy.fullname\" . }}"
+      labels:
+        helm.sh/chart: neon-proxy-{{ .Chart.Version }}
+        app.kubernetes.io/name: neon-proxy
+        app.kubernetes.io/instance: "{{ include \"neon-proxy.fullname\" . }}"
+        app.kubernetes.io/version: "{{ .Chart.AppVersion }}"
+        app.kubernetes.io/managed-by: Helm
+      namespace: "{{ .Release.Namespace }}"
+    spec:
+      selector:
+        matchLabels:
+          app.kubernetes.io/name: "neon-proxy"
+      endpoints:
+        - port: http
+          path: /metrics
+          interval: 10s
+          scrapeTimeout: 10s
+      namespaceSelector:
+        matchNames:
+          - "{{ .Release.Namespace }}"

.github/helm-values/prod-us-east-2-delta.neon-proxy-scram.yaml

@@ -10,6 +10,8 @@ settings:
   domain: "*.us-east-2.aws.neon.tech"
   sentryEnvironment: "production"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-release.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "10min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/prod-us-west-2-eta.neon-proxy-scram.yaml

@@ -10,6 +10,8 @@ settings:
   domain: "*.us-west-2.aws.neon.tech"
   sentryEnvironment: "production"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-release.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "10min"
 
 # -- Additional labels for neon-proxy pods
 podLabels:

.github/helm-values/production.proxy-scram.yaml

@@ -4,6 +4,8 @@ settings:
   domain: "*.cloud.neon.tech"
   sentryEnvironment: "production"
   wssPort: 8443
+  metricCollectionEndpoint: "http://console-release.local/billing/api/v1/usage_events"
+  metricCollectionInterval: "10min"
 
 podLabels:
   zenith_service: proxy-scram

.github/workflows/benchmarking.yml

@@ -489,3 +489,108 @@ jobs:
         slack-message: "Periodic TPC-H perf testing ${{ matrix.platform }}: ${{ job.status }}\n${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
       env:
         SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}
+
+  user-examples-compare:
+    if: success() || failure()
+    needs: [ tpch-compare ]
+
+    strategy:
+      fail-fast: false
+      matrix:
+        # neon-captest-prefetch: We have pre-created projects with prefetch enabled
+        # rds-aurora: Aurora Postgres Serverless v2 with autoscaling from 0.5 to 2 ACUs
+        # rds-postgres: RDS Postgres db.m5.large instance (2 vCPU, 8 GiB) with gp3 EBS storage
+        platform: [ neon-captest-prefetch, rds-postgres, rds-aurora ]
+
+    env:
+      POSTGRES_DISTRIB_DIR: /tmp/neon/pg_install
+      DEFAULT_PG_VERSION: 14
+      TEST_OUTPUT: /tmp/test_output
+      BUILD_TYPE: remote
+      SAVE_PERF_REPORT: ${{ github.event.inputs.save_perf_report || ( github.ref == 'refs/heads/main' ) }}
+      PLATFORM: ${{ matrix.platform }}
+
+    runs-on: [ self-hosted, us-east-2, x64 ]
+    container:
+      image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
+      options: --init
+
+    timeout-minutes: 360 # 6h
+
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Download Neon artifact
+      uses: ./.github/actions/download
+      with:
+        name: neon-${{ runner.os }}-release-artifact
+        path: /tmp/neon/
+        prefix: latest
+
+    - name: Add Postgres binaries to PATH
+      run: |
+        ${POSTGRES_DISTRIB_DIR}/v${DEFAULT_PG_VERSION}/bin/pgbench --version
+        echo "${POSTGRES_DISTRIB_DIR}/v${DEFAULT_PG_VERSION}/bin" >> $GITHUB_PATH
+
+    - name: Set up Connection String
+      id: set-up-connstr
+      run: |
+        case "${PLATFORM}" in
+          neon-captest-prefetch)
+            CONNSTR=${{ secrets.BENCHMARK_USER_EXAMPLE_CAPTEST_CONNSTR }}
+            ;;
+          rds-aurora)
+            CONNSTR=${{ secrets.BENCHMARK_USER_EXAMPLE_RDS_AURORA_CONNSTR }}
+            ;;
+          rds-postgres)
+            CONNSTR=${{ secrets.BENCHMARK_USER_EXAMPLE_RDS_POSTGRES_CONNSTR }}
+            ;;
+          *)
+            echo 2>&1 "Unknown PLATFORM=${PLATFORM}. Allowed only 'neon-captest-prefetch', 'rds-aurora', or 'rds-postgres'"
+            exit 1
+            ;;
+        esac
+
+        echo "connstr=${CONNSTR}" >> $GITHUB_OUTPUT
+
+        psql ${CONNSTR} -c "SELECT version();"
+
+    - name: Set database options
+      if: matrix.platform == 'neon-captest-prefetch'
+      run: |
+        DB_NAME=$(psql ${BENCHMARK_CONNSTR} --no-align --quiet -t -c "SELECT current_database()")
+
+        psql ${BENCHMARK_CONNSTR} -c "ALTER DATABASE ${DB_NAME} SET enable_seqscan_prefetch=on"
+        psql ${BENCHMARK_CONNSTR} -c "ALTER DATABASE ${DB_NAME} SET effective_io_concurrency=32"
+        psql ${BENCHMARK_CONNSTR} -c "ALTER DATABASE ${DB_NAME} SET maintenance_io_concurrency=32"
+      env:
+        BENCHMARK_CONNSTR: ${{ steps.set-up-connstr.outputs.connstr }}
+
+    - name: Run user examples
+      uses: ./.github/actions/run-python-test-set
+      with:
+        build_type: ${{ env.BUILD_TYPE }}
+        test_selection: performance/test_perf_olap.py
+        run_in_parallel: false
+        save_perf_report: ${{ env.SAVE_PERF_REPORT }}
+        extra_params: -m remote_cluster --timeout 21600 -k test_user_examples
+      env:
+        VIP_VAP_ACCESS_TOKEN: "${{ secrets.VIP_VAP_ACCESS_TOKEN }}"
+        PERF_TEST_RESULT_CONNSTR: "${{ secrets.PERF_TEST_RESULT_CONNSTR }}"
+        BENCHMARK_CONNSTR: ${{ steps.set-up-connstr.outputs.connstr }}
+
+    - name: Create Allure report
+      if: success() || failure()
+      uses: ./.github/actions/allure-report
+      with:
+        action: generate
+        build_type: ${{ env.BUILD_TYPE }}
+
+    - name: Post to a Slack channel
+      if: ${{ github.event.schedule && failure() }}
+      uses: slackapi/slack-github-action@v1
+      with:
+        channel-id: "C033QLM5P7D" # dev-staging-stream
+        slack-message: "Periodic TPC-H perf testing ${{ matrix.platform }}: ${{ job.status }}\n${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
+      env:
+        SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}

.github/workflows/build_and_test.yml

@@ -19,10 +19,12 @@ concurrency:
 env:
   RUST_BACKTRACE: 1
   COPT: '-Werror'
+  AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_DEV }}
+  AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_KEY_DEV }}
 
 jobs:
   tag:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/base:pinned
     outputs:
       build-tag: ${{steps.build-tag.outputs.tag}}
@@ -50,7 +52,7 @@ jobs:
         id: build-tag
 
   check-codestyle-python:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cloud:pinned
       options: --init
@@ -85,7 +87,7 @@ jobs:
         run: poetry run mypy .
 
   check-codestyle-rust:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -97,16 +99,16 @@ jobs:
           submodules: true
           fetch-depth: 1
 
-      - name: Restore cargo deps cache
-        id: cache_cargo
-        uses: actions/cache@v3
-        with:
-          path: |
-            ~/.cargo/registry/
-            !~/.cargo/registry/src
-            ~/.cargo/git/
-            target/
-          key: v1-${{ runner.os }}-cargo-clippy-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
+#      Disabled for now
+#      - name: Restore cargo deps cache
+#        id: cache_cargo
+#        uses: actions/cache@v3
+#        with:
+#          path: |
+#            !~/.cargo/registry/src
+#            ~/.cargo/git/
+#            target/
+#          key: v1-${{ runner.os }}-cargo-clippy-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
 
       # Some of our rust modules use FFI and need those to be checked
       - name: Get postgres headers
@@ -133,7 +135,7 @@ jobs:
         run: cargo deny check
 
   build-neon:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -141,7 +143,6 @@ jobs:
       fail-fast: false
       matrix:
         build_type: [ debug, release ]
-
     env:
       BUILD_TYPE: ${{ matrix.build_type }}
       GIT_VERSION: ${{ github.sha }}
@@ -194,24 +195,26 @@ jobs:
           echo "cov_prefix=${cov_prefix}" >> $GITHUB_ENV
           echo "CARGO_FEATURES=${CARGO_FEATURES}" >> $GITHUB_ENV
           echo "CARGO_FLAGS=${CARGO_FLAGS}" >> $GITHUB_ENV
+          echo "CARGO_HOME=${GITHUB_WORKSPACE}/.cargo" >> $GITHUB_ENV
 
+      # Disabled for now
       # Don't include the ~/.cargo/registry/src directory. It contains just
       # uncompressed versions of the crates in ~/.cargo/registry/cache
       # directory, and it's faster to let 'cargo' to rebuild it from the
       # compressed crates.
-      - name: Cache cargo deps
-        id: cache_cargo
-        uses: actions/cache@v3
-        with:
-          path: |
-            ~/.cargo/registry/
-            !~/.cargo/registry/src
-            ~/.cargo/git/
-            target/
-          # Fall back to older versions of the key, if no cache for current Cargo.lock was found
-          key: |
-            v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
-            v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-
+#      - name: Cache cargo deps
+#        id: cache_cargo
+#        uses: actions/cache@v3
+#        with:
+#          path: |
+#            ~/.cargo/registry/
+#            !~/.cargo/registry/src
+#            ~/.cargo/git/
+#            target/
+#          # Fall back to older versions of the key, if no cache for current Cargo.lock was found
+#          key: |
+#            v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
+#            v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-
 
       - name: Cache postgres v14 build
         id: cache_pg_14
@@ -301,7 +304,7 @@ jobs:
         uses: ./.github/actions/save-coverage-data
 
   regress-tests:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -334,7 +337,7 @@ jobs:
         uses: ./.github/actions/save-coverage-data
 
   benchmarks:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -365,7 +368,7 @@ jobs:
       # while coverage is currently collected for the debug ones
 
   merge-allure-report:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -402,7 +405,7 @@ jobs:
           DATABASE_URL="$TEST_RESULT_CONNSTR" poetry run python3 scripts/ingest_regress_test_result.py --revision ${SHA} --reference ${GITHUB_REF} --build-type ${BUILD_TYPE} --ingest suites.json
 
   coverage-report:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init
@@ -418,16 +421,17 @@ jobs:
           submodules: true
           fetch-depth: 1
 
-      - name: Restore cargo deps cache
-        id: cache_cargo
-        uses: actions/cache@v3
-        with:
-          path: |
-            ~/.cargo/registry/
-            !~/.cargo/registry/src
-            ~/.cargo/git/
-            target/
-          key: v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
+#      Disabled for now
+#      - name: Restore cargo deps cache
+#        id: cache_cargo
+#        uses: actions/cache@v3
+#        with:
+#          path: |
+#            ~/.cargo/registry/
+#            !~/.cargo/registry/src
+#            ~/.cargo/git/
+#            target/
+#          key: v1-${{ runner.os }}-${{ matrix.build_type }}-cargo-${{ hashFiles('rust-toolchain.toml') }}-${{ hashFiles('Cargo.lock') }}
 
       - name: Get Neon artifact
         uses: ./.github/actions/download
@@ -477,7 +481,7 @@ jobs:
             }"
 
   trigger-e2e-tests:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/base:pinned
       options: --init
@@ -522,9 +526,10 @@ jobs:
             }"
 
   neon-image:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     needs: [ tag ]
-    container: gcr.io/kaniko-project/executor:v1.9.0-debug
+    # https://github.com/GoogleContainerTools/kaniko/issues/2005
+    container: gcr.io/kaniko-project/executor:v1.7.0-debug
     defaults:
       run:
         shell: sh -eu {0}
@@ -540,12 +545,16 @@ jobs:
         run: echo "{\"credsStore\":\"ecr-login\"}" > /kaniko/.docker/config.json
 
       - name: Kaniko build neon
-        run: /kaniko/executor --snapshotMode=redo --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache --snapshotMode=redo --context . --build-arg GIT_VERSION=${{ github.sha }} --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/neon:${{needs.tag.outputs.build-tag}}
+        run: /kaniko/executor --reproducible --snapshotMode=redo --skip-unused-stages --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache --context . --build-arg GIT_VERSION=${{ github.sha }} --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/neon:${{needs.tag.outputs.build-tag}}
+
+      # Cleanup script fails otherwise - rm: cannot remove '/nvme/actions-runner/_work/_temp/_github_home/.ecr': Permission denied
+      - name: Cleanup ECR folder
+        run: rm -rf ~/.ecr
 
   compute-tools-image:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     needs: [ tag ]
-    container: gcr.io/kaniko-project/executor:v1.9.0-debug
+    container: gcr.io/kaniko-project/executor:v1.7.0-debug
     defaults:
       run:
         shell: sh -eu {0}
@@ -558,11 +567,14 @@ jobs:
         run: echo "{\"credsStore\":\"ecr-login\"}" > /kaniko/.docker/config.json
 
       - name: Kaniko build compute tools
-        run: /kaniko/executor --snapshotMode=redo --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache --snapshotMode=redo --context . --build-arg GIT_VERSION=${{ github.sha }} --dockerfile Dockerfile.compute-tools --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-tools:${{needs.tag.outputs.build-tag}}
+        run: /kaniko/executor --reproducible --snapshotMode=redo --skip-unused-stages --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache --context . --build-arg GIT_VERSION=${{ github.sha }} --dockerfile Dockerfile.compute-tools --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-tools:${{needs.tag.outputs.build-tag}}
+
+      - name: Cleanup ECR folder
+        run: rm -rf ~/.ecr
 
   compute-node-image:
-    runs-on: [ self-hosted, dev, x64 ]
-    container: gcr.io/kaniko-project/executor:v1.9.0-debug
+    runs-on: [ self-hosted, gen3, large ]
+    container: gcr.io/kaniko-project/executor:v1.7.0-debug
     needs: [ tag ]
     strategy:
       fail-fast: false
@@ -583,10 +595,13 @@ jobs:
         run: echo "{\"credsStore\":\"ecr-login\"}" > /kaniko/.docker/config.json
 
       - name: Kaniko build compute node with extensions
-        run: /kaniko/executor --skip-unused-stages  --snapshotMode=redo --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache  --context . --build-arg GIT_VERSION=${{ github.sha }} --dockerfile Dockerfile.compute-node-${{ matrix.version }} --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}}
+        run: /kaniko/executor --reproducible --snapshotMode=redo --skip-unused-stages --cache=true --cache-repo 369495373322.dkr.ecr.eu-central-1.amazonaws.com/cache  --context . --build-arg GIT_VERSION=${{ github.sha }} --build-arg PG_VERSION=${{ matrix.version }} --dockerfile Dockerfile.compute-node --destination 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}}
+
+      - name: Cleanup ECR folder
+        run: rm -rf ~/.ecr
 
   vm-compute-node-image:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, large ]
     needs: [ tag, compute-node-image ]
     strategy:
       fail-fast: false
@@ -595,6 +610,8 @@ jobs:
     defaults:
       run:
         shell: sh -eu {0}
+    env:
+      VM_INFORMANT_VERSION: 0.1.1
 
     steps:
       - name: Downloading latest vm-builder
@@ -606,9 +623,22 @@ jobs:
         run: |
           docker pull 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}}
 
+      - name: Downloading VM informant version ${{ env.VM_INFORMANT_VERSION }}
+        run: |
+          curl -fL https://github.com/neondatabase/autoscaling/releases/download/${{ env.VM_INFORMANT_VERSION }}/vm-informant -o vm-informant
+          chmod +x vm-informant
+
+      - name: Adding VM informant to compute-node image
+        run: |
+          ID=$(docker create 369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}})
+          docker cp vm-informant $ID:/bin/vm-informant
+          docker commit $ID temp-vm-compute-node
+          docker rm -f $ID
+
       - name: Build vm image
         run: |
-          ./vm-builder -src=369495373322.dkr.ecr.eu-central-1.amazonaws.com/compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}} -dst=369495373322.dkr.ecr.eu-central-1.amazonaws.com/vm-compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}}
+          # note: as of 2023-01-12, vm-builder requires a trailing ":latest" for local images
+          ./vm-builder -src=temp-vm-compute-node:latest -dst=369495373322.dkr.ecr.eu-central-1.amazonaws.com/vm-compute-node-${{ matrix.version }}:${{needs.tag.outputs.build-tag}}
 
       - name: Pushing vm-compute-node image
         run: |
@@ -616,7 +646,7 @@ jobs:
 
   test-images:
     needs: [ tag, neon-image, compute-node-image, compute-tools-image ]
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
 
     steps:
       - name: Checkout
@@ -658,7 +688,7 @@ jobs:
           docker compose -f ./docker-compose/docker-compose.yml down
 
   promote-images:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     needs: [ tag, test-images, vm-compute-node-image ]
     if: github.event_name != 'workflow_dispatch'
     container: amazon/aws-cli
@@ -666,6 +696,8 @@ jobs:
       fail-fast: false
       matrix:
         name: [ neon, compute-node-v14, vm-compute-node-v14, compute-node-v15, vm-compute-node-v15, compute-tools]
+    env:
+      AWS_DEFAULT_REGION: eu-central-1
 
     steps:
       - name: Promote image to latest
@@ -761,8 +793,11 @@ jobs:
           crane tag neondatabase/compute-node-v15:${{needs.tag.outputs.build-tag}} latest
           crane tag neondatabase/vm-compute-node-v15:${{needs.tag.outputs.build-tag}} latest
 
+      - name: Cleanup ECR folder
+        run: rm -rf ~/.ecr
+
   calculate-deploy-targets:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     if: |
       github.ref_name == 'release' &&
       github.event_name != 'workflow_dispatch'
@@ -780,7 +815,7 @@ jobs:
           fi
 
   deploy:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/ansible:pinned
     # We need both storage **and** compute images for deploy, because control plane picks the compute version based on the storage version.
     # If it notices a fresh storage it may bump the compute version. And if compute image failed to build it may break things badly
@@ -828,7 +863,7 @@ jobs:
           rm -f neon_install.tar.gz .neon_current_version
 
   deploy-new:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/ansible:pinned
     # We need both storage **and** compute images for deploy, because control plane picks the compute version based on the storage version.
     # If it notices a fresh storage it may bump the compute version. And if compute image failed to build it may break things badly
@@ -868,7 +903,7 @@ jobs:
           rm -f neon_install.tar.gz .neon_current_version
 
   deploy-pr-test-new:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/ansible:pinned
     # We need both storage **and** compute images for deploy, because control plane picks the compute version based on the storage version.
     # If it notices a fresh storage it may bump the compute version. And if compute image failed to build it may break things badly
@@ -943,7 +978,7 @@ jobs:
           rm -f neon_install.tar.gz .neon_current_version
 
   deploy-proxy:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/base:pinned
     # Compute image isn't strictly required for proxy deploy, but let's still wait for it to run all deploy jobs consistently.
     needs: [ push-docker-hub, calculate-deploy-targets, tag, regress-tests ]
@@ -988,7 +1023,7 @@ jobs:
 
   deploy-storage-broker:
     name: deploy storage broker on old staging and old prod
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/base:pinned
     # Compute image isn't strictly required for proxy deploy, but let's still wait for it to run all deploy jobs consistently.
     needs: [ push-docker-hub, calculate-deploy-targets, tag, regress-tests ]
@@ -1030,7 +1065,7 @@ jobs:
           helm upgrade neon-storage-broker neondatabase/neon-storage-broker --namespace ${{ matrix.storage_broker_ns }} --create-namespace --install --atomic -f .github/helm-values/${{ matrix.storage_broker_config }}.yaml --set image.tag=${{ needs.tag.outputs.build-tag }} --set settings.sentryUrl=${{ secrets.SENTRY_URL_BROKER }} --wait --timeout 5m0s
 
   deploy-proxy-new:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/ansible:pinned
     # Compute image isn't strictly required for proxy deploy, but let's still wait for it to run all deploy jobs consistently.
     needs: [ push-docker-hub, tag, regress-tests ]
@@ -1083,7 +1118,7 @@ jobs:
           helm upgrade neon-proxy-scram-legacy neondatabase/neon-proxy --namespace neon-proxy --create-namespace --install --atomic -f .github/helm-values/${{ matrix.target_cluster }}.neon-proxy-scram-legacy.yaml --set image.tag=${DOCKER_TAG} --set settings.sentryUrl=${{ secrets.SENTRY_URL_PROXY }} --wait --timeout 15m0s
 
   deploy-storage-broker-dev-new:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/ansible:pinned
     # Compute image isn't strictly required for proxy deploy, but let's still wait for it to run all deploy jobs consistently.
     needs: [ push-docker-hub, tag, regress-tests ]
@@ -1134,12 +1169,16 @@ jobs:
         include:
           - target_region:  us-east-2
             target_cluster: prod-us-east-2-delta
+            deploy_link_proxy: true
           - target_region:  us-west-2
             target_cluster: prod-us-west-2-eta
+            deploy_link_proxy: false
           - target_region: eu-central-1
             target_cluster: prod-eu-central-1-gamma
+            deploy_link_proxy: false
           - target_region: ap-southeast-1
             target_cluster: prod-ap-southeast-1-epsilon
+            deploy_link_proxy: false
     environment:
       name: prod-${{ matrix.target_region }}
     steps:
@@ -1154,11 +1193,17 @@ jobs:
           helm repo add neondatabase https://neondatabase.github.io/helm-charts
           aws --region ${{ matrix.target_region }} eks update-kubeconfig --name  ${{ matrix.target_cluster }}
 
-      - name: Re-deploy proxy
+      - name: Re-deploy scram proxy
         run: |
           DOCKER_TAG=${{needs.tag.outputs.build-tag}}
           helm upgrade neon-proxy-scram neondatabase/neon-proxy --namespace neon-proxy --create-namespace --install --atomic -f .github/helm-values/${{ matrix.target_cluster }}.neon-proxy-scram.yaml --set image.tag=${DOCKER_TAG} --set settings.sentryUrl=${{ secrets.SENTRY_URL_PROXY }} --wait --timeout 15m0s
 
+      - name: Re-deploy link proxy
+        if: matrix.deploy_link_proxy
+        run: |
+          DOCKER_TAG=${{needs.tag.outputs.build-tag}}
+          helm upgrade neon-proxy-link neondatabase/neon-proxy --namespace neon-proxy --create-namespace --install --atomic -f .github/helm-values/${{ matrix.target_cluster }}.neon-proxy-link.yaml --set image.tag=${DOCKER_TAG} --set settings.sentryUrl=${{ secrets.SENTRY_URL_PROXY }} --wait --timeout 15m0s
+
   deploy-storage-broker-prod-new:
     runs-on: prod
     container: 093970136003.dkr.ecr.eu-central-1.amazonaws.com/ansible:latest
@@ -1200,7 +1245,7 @@ jobs:
           helm upgrade neon-storage-broker-lb neondatabase/neon-storage-broker --namespace neon-storage-broker-lb --create-namespace --install --atomic -f .github/helm-values/${{ matrix.target_cluster }}.neon-storage-broker.yaml --set image.tag=${{ needs.tag.outputs.build-tag }} --set settings.sentryUrl=${{ secrets.SENTRY_URL_BROKER }} --wait --timeout 5m0s
 
   promote-compatibility-data:
-    runs-on: [ self-hosted, dev, x64 ]
+    runs-on: [ self-hosted, gen3, small ]
     container:
       image: 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:pinned
       options: --init

Cargo.toml

@@ -10,6 +10,145 @@ members = [
     "libs/*",
 ]
 
+[workspace.package]
+edition = "2021"
+license = "Apache-2.0"
+
+## All dependency versions, used in the project
+[workspace.dependencies]
+anyhow = { version = "1.0", features = ["backtrace"] }
+async-stream = "0.3"
+async-trait = "0.1"
+atty = "0.2.14"
+aws-config = { version = "0.51.0", default-features = false, features=["rustls"] }
+aws-sdk-s3 = "0.21.0"
+aws-smithy-http = "0.51.0"
+aws-types = "0.51.0"
+base64 = "0.13.0"
+bincode = "1.3"
+bindgen = "0.61"
+bstr = "1.0"
+byteorder = "1.4"
+bytes = "1.0"
+chrono = { version = "0.4", default-features = false, features = ["clock"] }
+clap = "4.0"
+close_fds = "0.3.2"
+comfy-table = "6.1"
+const_format = "0.2"
+crc32c = "0.6"
+crossbeam-utils = "0.8.5"
+fail = "0.5.0"
+fs2 = "0.4.3"
+futures = "0.3"
+futures-core = "0.3"
+futures-util = "0.3"
+git-version = "0.3"
+hashbrown = "0.13"
+hex = "0.4"
+hex-literal = "0.3"
+hmac = "0.12.1"
+hostname = "0.3.1"
+humantime = "2.1"
+humantime-serde = "1.1.1"
+hyper = "0.14"
+hyper-tungstenite = "0.9"
+itertools = "0.10"
+jsonwebtoken = "8"
+libc = "0.2"
+md5 = "0.7.0"
+memoffset = "0.8"
+nix = "0.26"
+notify = "5.0.0"
+num-traits = "0.2.15"
+once_cell = "1.13"
+opentelemetry = "0.18.0"
+opentelemetry-otlp = { version = "0.11.0", default_features=false, features = ["http-proto", "trace", "http", "reqwest-client"] }
+opentelemetry-semantic-conventions = "0.10.0"
+tracing-opentelemetry = "0.18.0"
+parking_lot = "0.12"
+pin-project-lite = "0.2"
+prometheus = {version = "0.13", default_features=false, features = ["process"]} # removes protobuf dependency
+prost = "0.11"
+rand = "0.8"
+regex = "1.4"
+reqwest = { version = "0.11", default-features = false, features = ["rustls-tls"] }
+routerify = "3"
+rpds = "0.12.0"
+rustls = "0.20"
+rustls-pemfile = "1"
+rustls-split = "0.3"
+scopeguard = "1.1"
+sentry = { version = "0.29", default-features = false, features = ["backtrace", "contexts", "panic", "rustls", "reqwest" ] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1"
+serde_with = "2.0"
+sha2 = "0.10.2"
+signal-hook = "0.3"
+socket2 = "0.4.4"
+strum = "0.24"
+strum_macros = "0.24"
+svg_fmt = "0.4.1"
+tar = "0.4"
+thiserror = "1.0"
+tls-listener = { version = "0.6", features = ["rustls", "hyper-h1"] }
+tokio = { version = "1.17", features = ["macros"] }
+tokio-postgres-rustls = "0.9.0"
+tokio-rustls = "0.23"
+tokio-stream = "0.1"
+tokio-util = { version = "0.7", features = ["io"] }
+toml = "0.5"
+toml_edit = { version = "0.17", features = ["easy"] }
+tonic = {version = "0.8", features = ["tls", "tls-roots"]}
+tracing = "0.1"
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }
+url = "2.2"
+uuid = { version = "1.2", features = ["v4", "serde"] }
+walkdir = "2.3.2"
+webpki-roots = "0.22.5"
+x509-parser = "0.14"
+
+## TODO replace this with tracing
+env_logger = "0.10"
+log = "0.4"
+
+## Libraries from neondatabase/ git forks, ideally with changes to be upstreamed
+postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+postgres-types = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+tokio-tar = { git = "https://github.com/neondatabase/tokio-tar.git", rev="404df61437de0feef49ba2ccdbdd94eb8ad6e142" }
+
+## Local libraries
+consumption_metrics = { version = "0.1", path = "./libs/consumption_metrics/" }
+metrics = { version = "0.1", path = "./libs/metrics/" }
+pageserver_api = { version = "0.1", path = "./libs/pageserver_api/" }
+postgres_connection = { version = "0.1", path = "./libs/postgres_connection/" }
+postgres_ffi = { version = "0.1", path = "./libs/postgres_ffi/" }
+pq_proto = { version = "0.1", path = "./libs/pq_proto/" }
+remote_storage = { version = "0.1", path = "./libs/remote_storage/" }
+safekeeper_api = { version = "0.1", path = "./libs/safekeeper_api" }
+storage_broker = { version = "0.1", path = "./storage_broker/" } # Note: main broker code is inside the binary crate, so linking with the library shouldn't be heavy.
+tenant_size_model = { version = "0.1", path = "./libs/tenant_size_model/" }
+tracing-utils = { version = "0.1", path = "./libs/tracing-utils/" }
+utils = { version = "0.1", path = "./libs/utils/" }
+
+## Common library dependency
+workspace_hack = { version = "0.1", path = "./workspace_hack/" }
+
+## Build dependencies
+criterion = "0.4"
+rcgen = "0.10"
+rstest = "0.16"
+tempfile = "3.2"
+tonic-build = "0.8"
+
+# This is only needed for proxy's tests.
+# TODO: we should probably fork `tokio-postgres-rustls` instead.
+[patch.crates-io]
+tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+
+################# Binary contents sections
+
 [profile.release]
 # This is useful for profiling and, to some extent, debug.
 # Besides, debug info should not affect the performance.
@@ -70,9 +209,3 @@ inherits = "release"
 debug = false # true = 2 = all symbols, 1 = line only
 opt-level = "z"
 lto = true
-
-
-# This is only needed for proxy's tests.
-# TODO: we should probably fork `tokio-postgres-rustls` instead.
-[patch.crates-io]
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }

Dockerfile.compute-node

@@ -1,8 +1,5 @@
-#
-# This file is identical to the Dockerfile.compute-node-v15 file
-# except for the version of Postgres that is built.
-#
-
+ARG REPOSITORY=369495373322.dkr.ecr.eu-central-1.amazonaws.com
+ARG IMAGE=rust
 ARG TAG=pinned
 
 #########################################################################################
@@ -22,7 +19,8 @@ RUN apt update &&  \
 #
 #########################################################################################
 FROM build-deps AS pg-build
-COPY vendor/postgres-v14 postgres
+ARG PG_VERSION
+COPY vendor/postgres-${PG_VERSION} postgres
 RUN cd postgres && \
     ./configure CFLAGS='-O2 -g3' --enable-debug --with-openssl --with-uuid=ossp && \
     make MAKELEVEL=0 -j $(getconf _NPROCESSORS_ONLN) -s install && \
@@ -34,7 +32,8 @@ RUN cd postgres && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/bloom.control && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/pgrowlocks.control && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/intagg.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/pgstattuple.control
+    echo 'trusted = true' >> /usr/local/pgsql/share/extension/pgstattuple.control && \
+    echo 'trusted = true' >> /usr/local/pgsql/share/extension/earthdistance.control
 
 #########################################################################################
 #
@@ -62,8 +61,7 @@ RUN wget https://download.osgeo.org/postgis/source/postgis-3.3.1.tar.gz && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_tiger_geocoder.control && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_topology.control && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/address_standardizer.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/address_standardizer_data_us.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_sfcgal.control
+    echo 'trusted = true' >> /usr/local/pgsql/share/extension/address_standardizer_data_us.control
 
 #########################################################################################
 #
@@ -135,6 +133,27 @@ RUN wget https://github.com/zachasme/h3-pg/archive/refs/tags/v4.0.1.tar.gz -O h3
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/h3.control && \
     echo 'trusted = true' >> /usr/local/pgsql/share/extension/h3_postgis.control
 
+#########################################################################################
+#
+# Layer "unit-pg-build"
+# compile unit extension
+#
+#########################################################################################
+FROM build-deps AS unit-pg-build
+COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/
+
+RUN wget https://github.com/df7cb/postgresql-unit/archive/refs/tags/7.7.tar.gz && \
+    tar xvzf 7.7.tar.gz && \
+    cd postgresql-unit-7.7 && \
+    make -j $(getconf _NPROCESSORS_ONLN) PG_CONFIG=/usr/local/pgsql/bin/pg_config && \
+    make -j $(getconf _NPROCESSORS_ONLN) install PG_CONFIG=/usr/local/pgsql/bin/pg_config && \
+    # unit extension's "create extension" script relies on absolute install path to fill some reference tables.
+    # We move the extension from '/usr/local/pgsql/' to '/usr/local/'  after it is build. So we need to adjust the path.
+    # This one-liner removes pgsql/ part of the path.
+    # NOTE: Other extensions that rely on MODULEDIR variable after building phase will need the same fix.
+    find /usr/local/pgsql/share/extension/ -name "unit*.sql" -print0 | xargs -0 sed -i "s|pgsql/||g" && \
+    echo 'trusted = true' >> /usr/local/pgsql/share/extension/unit.control
+
 #########################################################################################
 #
 # Layer "neon-pg-ext-build"
@@ -146,6 +165,7 @@ COPY --from=postgis-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=plv8-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=h3-pg-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY --from=h3-pg-build /h3/usr /
+COPY --from=unit-pg-build /usr/local/pgsql/ /usr/local/pgsql/
 COPY pgxn/ pgxn/
 
 RUN make -j $(getconf _NPROCESSORS_ONLN) \
@@ -158,7 +178,7 @@ RUN make -j $(getconf _NPROCESSORS_ONLN) \
 # Compile and run the Neon-specific `compute_ctl` binary
 #
 #########################################################################################
-FROM 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:$TAG AS compute-tools
+FROM $REPOSITORY/$IMAGE:$TAG AS compute-tools
 USER nonroot
 # Copy entire project to get Cargo.* files with proper dependencies for the whole project
 COPY --chown=nonroot . .

Dockerfile.compute-node-v15

@@ -1,220 +0,0 @@
-#
-# This file is identical to the Dockerfile.compute-node-v14 file
-# except for the version of Postgres that is built.
-#
-
-ARG TAG=pinned
-
-#########################################################################################
-#
-# Layer "build-deps"
-#
-#########################################################################################
-FROM debian:bullseye-slim AS build-deps
-RUN apt update &&  \
-    apt install -y git autoconf automake libtool build-essential bison flex libreadline-dev \
-    zlib1g-dev libxml2-dev libcurl4-openssl-dev libossp-uuid-dev wget pkg-config libssl-dev
-
-#########################################################################################
-#
-# Layer "pg-build"
-# Build Postgres from the neon postgres repository.
-#
-#########################################################################################
-FROM build-deps AS pg-build
-COPY vendor/postgres-v15 postgres
-RUN cd postgres && \
-    ./configure CFLAGS='-O2 -g3' --enable-debug --with-openssl --with-uuid=ossp && \
-    make MAKELEVEL=0 -j $(getconf _NPROCESSORS_ONLN) -s install && \
-    make MAKELEVEL=0 -j $(getconf _NPROCESSORS_ONLN) -s -C contrib/ install && \
-    # Install headers
-    make MAKELEVEL=0 -j $(getconf _NPROCESSORS_ONLN) -s -C src/include install && \
-    make MAKELEVEL=0 -j $(getconf _NPROCESSORS_ONLN) -s -C src/interfaces/libpq install && \
-    # Enable some of contrib extensions
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/bloom.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/pgrowlocks.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/intagg.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/pgstattuple.control
-
-#########################################################################################
-#
-# Layer "postgis-build"
-# Build PostGIS from the upstream PostGIS mirror.
-#
-#########################################################################################
-FROM build-deps AS postgis-build
-COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/
-RUN apt update && \
-    apt install -y gdal-bin libgdal-dev libprotobuf-c-dev protobuf-c-compiler xsltproc
-
-RUN wget https://download.osgeo.org/postgis/source/postgis-3.3.1.tar.gz && \
-    tar xvzf postgis-3.3.1.tar.gz && \
-    cd postgis-3.3.1 && \
-    ./autogen.sh && \
-    export PATH="/usr/local/pgsql/bin:$PATH" && \
-    ./configure && \
-    make -j $(getconf _NPROCESSORS_ONLN) install && \
-    cd extensions/postgis && \
-    make clean && \
-    make -j $(getconf _NPROCESSORS_ONLN) install && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_raster.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_tiger_geocoder.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_topology.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/address_standardizer.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/address_standardizer_data_us.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/postgis_sfcgal.control
-
-#########################################################################################
-#
-# Layer "plv8-build"
-# Build plv8
-#
-#########################################################################################
-FROM build-deps AS plv8-build
-COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/
-RUN apt update && \
-    apt install -y ninja-build python3-dev libc++-dev libc++abi-dev libncurses5 binutils
-
-# https://github.com/plv8/plv8/issues/475:
-#   v8 uses gold for linking and sets `--thread-count=4` which breaks
-#   gold version <= 1.35 (https://sourceware.org/bugzilla/show_bug.cgi?id=23607)
-# Install newer gold version manually as debian-testing binutils version updates
-# libc version, which in turn breaks other extension built against non-testing libc.
-RUN wget https://ftp.gnu.org/gnu/binutils/binutils-2.38.tar.gz && \
-    tar xvzf binutils-2.38.tar.gz && \
-    cd binutils-2.38 && \
-    cd libiberty && ./configure && make -j $(getconf _NPROCESSORS_ONLN) && \
-    cd ../bfd && ./configure && make bfdver.h && \
-    cd ../gold && ./configure && make -j $(getconf _NPROCESSORS_ONLN) && make install && \
-    cp /usr/local/bin/ld.gold /usr/bin/gold
-
-# Sed is used to patch for https://github.com/plv8/plv8/issues/503
-RUN wget https://github.com/plv8/plv8/archive/refs/tags/v3.1.4.tar.gz && \
-    tar xvzf v3.1.4.tar.gz && \
-    cd plv8-3.1.4 && \
-    export PATH="/usr/local/pgsql/bin:$PATH" && \
-    sed -i 's/MemoryContextAlloc(/MemoryContextAllocZero(/' plv8.cc && \
-    make DOCKER=1 -j $(getconf _NPROCESSORS_ONLN) install && \
-    rm -rf /plv8-* && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/plv8.control
-
-#########################################################################################
-#
-# Layer "h3-pg-build"
-# Build h3_pg
-#
-#########################################################################################
-FROM build-deps AS h3-pg-build
-COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/
-
-# packaged cmake is too old
-RUN wget https://github.com/Kitware/CMake/releases/download/v3.24.2/cmake-3.24.2-linux-x86_64.sh \
-      -q -O /tmp/cmake-install.sh \
-      && chmod u+x /tmp/cmake-install.sh \
-      && /tmp/cmake-install.sh --skip-license --prefix=/usr/local/ \
-      && rm /tmp/cmake-install.sh
-
-RUN wget https://github.com/uber/h3/archive/refs/tags/v4.0.1.tar.gz -O h3.tgz && \
-    tar xvzf h3.tgz  && \
-    cd h3-4.0.1 && \
-    mkdir build && \
-    cd build && \
-    cmake .. -DCMAKE_BUILD_TYPE=Release && \
-    make -j $(getconf _NPROCESSORS_ONLN) && \
-    DESTDIR=/h3 make install && \
-    cp -R /h3/usr / && \
-    rm -rf build
-
-RUN wget https://github.com/zachasme/h3-pg/archive/refs/tags/v4.0.1.tar.gz -O h3-pg.tgz && \
-    tar xvzf h3-pg.tgz && \
-    cd h3-pg-4.0.1 && \
-    export PATH="/usr/local/pgsql/bin:$PATH" && \
-    make -j $(getconf _NPROCESSORS_ONLN) && \
-    make -j $(getconf _NPROCESSORS_ONLN) install && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/h3.control && \
-    echo 'trusted = true' >> /usr/local/pgsql/share/extension/h3_postgis.control
-
-#########################################################################################
-#
-# Layer "neon-pg-ext-build"
-# compile neon extensions
-#
-#########################################################################################
-FROM build-deps AS neon-pg-ext-build
-COPY --from=postgis-build /usr/local/pgsql/ /usr/local/pgsql/
-COPY --from=plv8-build /usr/local/pgsql/ /usr/local/pgsql/
-COPY --from=h3-pg-build /usr/local/pgsql/ /usr/local/pgsql/
-COPY --from=h3-pg-build /h3/usr /
-COPY pgxn/ pgxn/
-
-RUN make -j $(getconf _NPROCESSORS_ONLN) \
-        PG_CONFIG=/usr/local/pgsql/bin/pg_config \
-        -C pgxn/neon \
-        -s install
-
-#########################################################################################
-#
-# Compile and run the Neon-specific `compute_ctl` binary
-#
-#########################################################################################
-FROM 369495373322.dkr.ecr.eu-central-1.amazonaws.com/rust:$TAG AS compute-tools
-USER nonroot
-# Copy entire project to get Cargo.* files with proper dependencies for the whole project
-COPY --chown=nonroot . .
-RUN cd compute_tools && cargo build --locked --profile release-line-debug-size-lto
-
-#########################################################################################
-#
-# Clean up postgres folder before inclusion
-#
-#########################################################################################
-FROM neon-pg-ext-build AS postgres-cleanup-layer
-COPY --from=neon-pg-ext-build /usr/local/pgsql /usr/local/pgsql
-
-# Remove binaries from /bin/ that we won't use (or would manually copy & install otherwise)
-RUN cd /usr/local/pgsql/bin && rm ecpg raster2pgsql shp2pgsql pgtopo_export pgtopo_import pgsql2shp
-
-# Remove headers that we won't need anymore - we've completed installation of all extensions
-RUN rm -r /usr/local/pgsql/include
-
-# Remove static postgresql libraries - all compilation is finished, so we
-# can now remove these files - they must be included in other binaries by now
-# if they were to be used by other libraries.
-RUN rm /usr/local/pgsql/lib/lib*.a
-
-#########################################################################################
-#
-# Final layer
-# Put it all together into the final image
-#
-#########################################################################################
-FROM debian:bullseye-slim
-# Add user postgres
-RUN mkdir /var/db && useradd -m -d /var/db/postgres postgres && \
-    echo "postgres:test_console_pass" | chpasswd && \
-    mkdir /var/db/postgres/compute && mkdir /var/db/postgres/specs && \
-    chown -R postgres:postgres /var/db/postgres && \
-    chmod 0750 /var/db/postgres/compute && \
-    echo '/usr/local/lib' >> /etc/ld.so.conf && /sbin/ldconfig
-
-COPY --from=postgres-cleanup-layer --chown=postgres /usr/local/pgsql /usr/local
-COPY --from=compute-tools --chown=postgres /home/nonroot/target/release-line-debug-size-lto/compute_ctl /usr/local/bin/compute_ctl
-
-# Install:
-# libreadline8 for psql
-# libossp-uuid16 for extension ossp-uuid
-# libgeos, libgdal, libproj and libprotobuf-c1 for PostGIS
-RUN apt update &&  \
-    apt install --no-install-recommends -y \
-        libreadline8 \
-        libossp-uuid16 \
-        libgeos-c1v5 \
-        libgdal28 \
-        libproj19 \
-        libprotobuf-c1 \
-        gdb && \
-    rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
-
-USER postgres
-ENTRYPOINT ["/usr/local/bin/compute_ctl"]

compute_tools/Cargo.toml

@@ -1,24 +1,28 @@
 [package]
 name = "compute_tools"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = "1.0"
-chrono = { version = "0.4", default-features = false, features = ["clock"] }
-clap = "4.0"
-env_logger = "0.9"
-futures = "0.3.13"
-hyper = { version = "0.14", features = ["full"] }
-log = { version = "0.4", features = ["std", "serde"] }
-notify = "5.0.0"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-regex = "1"
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1"
-tar = "0.4"
-tokio = { version = "1.17", features = ["macros", "rt", "rt-multi-thread"] }
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-url = "2.2.2"
-workspace_hack = { version = "0.1", path = "../workspace_hack" }
+anyhow.workspace = true
+chrono.workspace = true
+clap.workspace = true
+futures.workspace = true
+hyper = { workspace = true, features = ["full"] }
+notify.workspace = true
+opentelemetry.workspace = true
+postgres.workspace = true
+regex.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+tar.workspace = true
+tokio = { workspace = true, features = ["rt", "rt-multi-thread"] }
+tokio-postgres.workspace = true
+tracing.workspace = true
+tracing-opentelemetry.workspace = true
+tracing-subscriber.workspace = true
+tracing-utils.workspace = true
+url.workspace = true
+
+workspace_hack.workspace = true

compute_tools/README.md

@@ -19,6 +19,10 @@ Also `compute_ctl` spawns two separate service threads:
 - `http-endpoint` runs a Hyper HTTP API server, which serves readiness and the
   last activity requests.
 
+If the `vm-informant` binary is present at `/bin/vm-informant`, it will also be started. For VM
+compute nodes, `vm-informant` communicates with the VM autoscaling system. It coordinates
+downscaling and (eventually) will request immediate upscaling under resource pressure.
+
 Usage example:
 ```sh
 compute_ctl -D /var/db/postgres/compute \

compute_tools/src/bin/compute_ctl.rs

@@ -18,6 +18,10 @@
 //! - `http-endpoint` runs a Hyper HTTP API server, which serves readiness and the
 //!   last activity requests.
 //!
+//! If the `vm-informant` binary is present at `/bin/vm-informant`, it will also be started. For VM
+//! compute nodes, `vm-informant` communicates with the VM autoscaling system. It coordinates
+//! downscaling and (eventually) will request immediate upscaling under resource pressure.
+//!
 //! Usage example:
 //! ```sh
 //! compute_ctl -D /var/db/postgres/compute \
@@ -36,10 +40,11 @@ use std::{thread, time::Duration};
 use anyhow::{Context, Result};
 use chrono::Utc;
 use clap::Arg;
-use log::{error, info};
+use tracing::{error, info};
 
 use compute_tools::compute::{ComputeMetrics, ComputeNode, ComputeState, ComputeStatus};
 use compute_tools::http::api::launch_http_server;
+use compute_tools::informant::spawn_vm_informant_if_present;
 use compute_tools::logger::*;
 use compute_tools::monitor::launch_monitor;
 use compute_tools::params::*;
@@ -48,8 +53,7 @@ use compute_tools::spec::*;
 use url::Url;
 
 fn main() -> Result<()> {
-    // TODO: re-use `utils::logging` later
-    init_logger(DEFAULT_LOG_LEVEL)?;
+    init_tracing_and_logging(DEFAULT_LOG_LEVEL)?;
 
     let matches = cli().get_matches();
 
@@ -80,6 +84,29 @@ fn main() -> Result<()> {
         }
     };
 
+    // Extract OpenTelemetry context for the startup actions from the spec, and
+    // attach it to the current tracing context.
+    //
+    // This is used to propagate the context for the 'start_compute' operation
+    // from the neon control plane. This allows linking together the wider
+    // 'start_compute' operation that creates the compute container, with the
+    // startup actions here within the container.
+    //
+    // Switch to the startup context here, and exit it once the startup has
+    // completed and Postgres is up and running.
+    //
+    // NOTE: This is supposed to only cover the *startup* actions. Once
+    // postgres is configured and up-and-running, we exit this span. Any other
+    // actions that are performed on incoming HTTP requests, for example, are
+    // performed in separate spans.
+    let startup_context_guard = if let Some(ref carrier) = spec.startup_tracing_context {
+        use opentelemetry::propagation::TextMapPropagator;
+        use opentelemetry::sdk::propagation::TraceContextPropagator;
+        Some(TraceContextPropagator::new().extract(carrier).attach())
+    } else {
+        None
+    };
+
     let pageserver_connstr = spec
         .cluster
         .settings
@@ -114,30 +141,55 @@ fn main() -> Result<()> {
     // requests, while configuration is still in progress.
     let _http_handle = launch_http_server(&compute).expect("cannot launch http endpoint thread");
     let _monitor_handle = launch_monitor(&compute).expect("cannot launch compute monitor thread");
+    // Also spawn the thread responsible for handling the VM informant -- if it's present
+    let _vm_informant_handle = spawn_vm_informant_if_present().expect("cannot launch VM informant");
 
-    // Run compute (Postgres) and hang waiting on it.
-    match compute.prepare_and_run() {
-        Ok(ec) => {
-            let code = ec.code().unwrap_or(1);
-            info!("Postgres exited with code {}, shutting down", code);
-            exit(code)
-        }
-        Err(error) => {
-            error!("could not start the compute node: {:?}", error);
-
+    // Start Postgres
+    let mut delay_exit = false;
+    let mut exit_code = None;
+    let pg = match compute.start_compute() {
+        Ok(pg) => Some(pg),
+        Err(err) => {
+            error!("could not start the compute node: {:?}", err);
             let mut state = compute.state.write().unwrap();
-            state.error = Some(format!("{:?}", error));
+            state.error = Some(format!("{:?}", err));
             state.status = ComputeStatus::Failed;
             drop(state);
-
-            // Keep serving HTTP requests, so the cloud control plane was able to
-            // get the actual error.
-            info!("giving control plane 30s to collect the error before shutdown");
-            thread::sleep(Duration::from_secs(30));
-            info!("shutting down");
-            Err(error)
+            delay_exit = true;
+            None
         }
+    };
+
+    // Wait for the child Postgres process forever. In this state Ctrl+C will
+    // propagate to Postgres and it will be shut down as well.
+    if let Some(mut pg) = pg {
+        // Startup is finished, exit the startup tracing span
+        drop(startup_context_guard);
+
+        let ecode = pg
+            .wait()
+            .expect("failed to start waiting on Postgres process");
+        info!("Postgres exited with code {}, shutting down", ecode);
+        exit_code = ecode.code()
     }
+
+    if let Err(err) = compute.check_for_core_dumps() {
+        error!("error while checking for core dumps: {err:?}");
+    }
+
+    // If launch failed, keep serving HTTP requests for a while, so the cloud
+    // control plane can get the actual error.
+    if delay_exit {
+        info!("giving control plane 30s to collect the error before shutdown");
+        thread::sleep(Duration::from_secs(30));
+        info!("shutting down");
+    }
+
+    // Shutdown trace pipeline gracefully, so that it has a chance to send any
+    // pending traces before we exit.
+    tracing_utils::shutdown_tracing();
+
+    exit(exit_code.unwrap_or(1))
 }
 
 fn cli() -> clap::Command {

compute_tools/src/checker.rs

@@ -1,10 +1,11 @@
 use anyhow::{anyhow, Result};
-use log::error;
 use postgres::Client;
 use tokio_postgres::NoTls;
+use tracing::{error, instrument};
 
 use crate::compute::ComputeNode;
 
+#[instrument(skip_all)]
 pub fn create_writability_check_data(client: &mut Client) -> Result<()> {
     let query = "
     CREATE TABLE IF NOT EXISTS health_check (
@@ -21,6 +22,7 @@ pub fn create_writability_check_data(client: &mut Client) -> Result<()> {
     Ok(())
 }
 
+#[instrument(skip_all)]
 pub async fn check_writability(compute: &ComputeNode) -> Result<()> {
     let (client, connection) = tokio_postgres::connect(compute.connstr.as_str(), NoTls).await?;
     if client.is_closed() {

compute_tools/src/compute.rs

@@ -17,15 +17,15 @@
 use std::fs;
 use std::os::unix::fs::PermissionsExt;
 use std::path::Path;
-use std::process::{Command, ExitStatus, Stdio};
+use std::process::{Command, Stdio};
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::sync::RwLock;
 
 use anyhow::{Context, Result};
 use chrono::{DateTime, Utc};
-use log::{info, warn};
 use postgres::{Client, NoTls};
 use serde::{Serialize, Serializer};
+use tracing::{info, instrument, warn};
 
 use crate::checker::create_writability_check_data;
 use crate::config;
@@ -121,6 +121,7 @@ impl ComputeNode {
 
     // Get basebackup from the libpq connection to pageserver using `connstr` and
     // unarchive it to `pgdata` directory overriding all its previous content.
+    #[instrument(skip(self))]
     fn get_basebackup(&self, lsn: &str) -> Result<()> {
         let start_time = Utc::now();
 
@@ -154,6 +155,7 @@ impl ComputeNode {
 
     // Run `postgres` in a special mode with `--sync-safekeepers` argument
     // and return the reported LSN back to the caller.
+    #[instrument(skip(self))]
     fn sync_safekeepers(&self) -> Result<String> {
         let start_time = Utc::now();
 
@@ -196,6 +198,7 @@ impl ComputeNode {
 
     /// Do all the preparations like PGDATA directory creation, configuration,
     /// safekeepers sync, basebackup, etc.
+    #[instrument(skip(self))]
     pub fn prepare_pgdata(&self) -> Result<()> {
         let spec = &self.spec;
         let pgdata_path = Path::new(&self.pgdata);
@@ -229,9 +232,8 @@ impl ComputeNode {
 
     /// Start Postgres as a child process and manage DBs/roles.
     /// After that this will hang waiting on the postmaster process to exit.
-    pub fn run(&self) -> Result<ExitStatus> {
-        let start_time = Utc::now();
-
+    #[instrument(skip(self))]
+    pub fn start_postgres(&self) -> Result<std::process::Child> {
         let pgdata_path = Path::new(&self.pgdata);
 
         // Run postgres as a child process.
@@ -242,10 +244,15 @@ impl ComputeNode {
 
         wait_for_postgres(&mut pg, pgdata_path)?;
 
+        Ok(pg)
+    }
+
+    #[instrument(skip(self))]
+    pub fn apply_config(&self) -> Result<()> {
         // If connection fails,
         // it may be the old node with `zenith_admin` superuser.
         //
-        // In this case we need to connect with old `zenith_admin`name
+        // In this case we need to connect with old `zenith_admin` name
         // and create new user. We cannot simply rename connected user,
         // but we can create a new one and grant it all privileges.
         let mut client = match Client::connect(self.connstr.as_str(), NoTls) {
@@ -271,6 +278,7 @@ impl ComputeNode {
             Ok(client) => client,
         };
 
+        // Proceed with post-startup configuration. Note, that order of operations is important.
         handle_roles(&self.spec, &mut client)?;
         handle_databases(&self.spec, &mut client)?;
         handle_role_deletions(self, &mut client)?;
@@ -279,8 +287,34 @@ impl ComputeNode {
 
         // 'Close' connection
         drop(client);
-        let startup_end_time = Utc::now();
 
+        info!(
+            "finished configuration of compute for project {}",
+            self.spec.cluster.cluster_id
+        );
+
+        Ok(())
+    }
+
+    #[instrument(skip(self))]
+    pub fn start_compute(&self) -> Result<std::process::Child> {
+        info!(
+            "starting compute for project {}, operation {}, tenant {}, timeline {}",
+            self.spec.cluster.cluster_id,
+            self.spec.operation_uuid.as_ref().unwrap(),
+            self.tenant,
+            self.timeline,
+        );
+
+        self.prepare_pgdata()?;
+
+        let start_time = Utc::now();
+
+        let pg = self.start_postgres()?;
+
+        self.apply_config()?;
+
+        let startup_end_time = Utc::now();
         self.metrics.config_ms.store(
             startup_end_time
                 .signed_duration_since(start_time)
@@ -300,34 +334,7 @@ impl ComputeNode {
 
         self.set_status(ComputeStatus::Running);
 
-        info!(
-            "finished configuration of compute for project {}",
-            self.spec.cluster.cluster_id
-        );
-
-        // Wait for child Postgres process basically forever. In this state Ctrl+C
-        // will propagate to Postgres and it will be shut down as well.
-        let ecode = pg
-            .wait()
-            .expect("failed to start waiting on Postgres process");
-
-        self.check_for_core_dumps()
-            .expect("failed to check for core dumps");
-
-        Ok(ecode)
-    }
-
-    pub fn prepare_and_run(&self) -> Result<ExitStatus> {
-        info!(
-            "starting compute for project {}, operation {}, tenant {}, timeline {}",
-            self.spec.cluster.cluster_id,
-            self.spec.operation_uuid.as_ref().unwrap(),
-            self.tenant,
-            self.timeline,
-        );
-
-        self.prepare_pgdata()?;
-        self.run()
+        Ok(pg)
     }
 
     // Look for core dumps and collect backtraces.
@@ -340,7 +347,7 @@ impl ComputeNode {
     //
     // Use that as a default location and pattern, except macos where core dumps are written
     // to /cores/ directory by default.
-    fn check_for_core_dumps(&self) -> Result<()> {
+    pub fn check_for_core_dumps(&self) -> Result<()> {
         let core_dump_dir = match std::env::consts::OS {
             "macos" => Path::new("/cores/"),
             _ => Path::new(&self.pgdata),

compute_tools/src/http/api.rs

@@ -6,13 +6,19 @@ use std::thread;
 use anyhow::Result;
 use hyper::service::{make_service_fn, service_fn};
 use hyper::{Body, Method, Request, Response, Server, StatusCode};
-use log::{error, info};
 use serde_json;
+use tracing::{error, info};
+use tracing_utils::http::OtelName;
 
 use crate::compute::ComputeNode;
 
 // Service function to handle all available routes.
-async fn routes(req: Request<Body>, compute: Arc<ComputeNode>) -> Response<Body> {
+async fn routes(req: Request<Body>, compute: &Arc<ComputeNode>) -> Response<Body> {
+    //
+    // NOTE: The URI path is currently included in traces. That's OK because
+    // it doesn't contain any variable parts or sensitive information. But
+    // please keep that in mind if you change the routing here.
+    //
     match (req.method(), req.uri().path()) {
         // Serialized compute state.
         (&Method::GET, "/status") => {
@@ -30,7 +36,7 @@ async fn routes(req: Request<Body>, compute: Arc<ComputeNode>) -> Response<Body>
 
         (&Method::POST, "/check_writability") => {
             info!("serving /check_writability POST request");
-            let res = crate::checker::check_writability(&compute).await;
+            let res = crate::checker::check_writability(compute).await;
             match res {
                 Ok(_) => Response::new(Body::from("true")),
                 Err(e) => Response::new(Body::from(e.to_string())),
@@ -56,7 +62,19 @@ async fn serve(state: Arc<ComputeNode>) {
         async move {
             Ok::<_, Infallible>(service_fn(move |req: Request<Body>| {
                 let state = state.clone();
-                async move { Ok::<_, Infallible>(routes(req, state).await) }
+                async move {
+                    Ok::<_, Infallible>(
+                        // NOTE: We include the URI path in the string. It
+                        // doesn't contain any variable parts or sensitive
+                        // information in this API.
+                        tracing_utils::http::tracing_handler(
+                            req,
+                            |req| routes(req, &state),
+                            OtelName::UriPath,
+                        )
+                        .await,
+                    )
+                }
             }))
         }
     });

compute_tools/src/informant.rs

@@ -0,0 +1,50 @@
+use std::path::Path;
+use std::process;
+use std::thread;
+use std::time::Duration;
+use tracing::{info, warn};
+
+use anyhow::{Context, Result};
+
+const VM_INFORMANT_PATH: &str = "/bin/vm-informant";
+const RESTART_INFORMANT_AFTER_MILLIS: u64 = 5000;
+
+/// Launch a thread to start the VM informant if it's present (and restart, on failure)
+pub fn spawn_vm_informant_if_present() -> Result<Option<thread::JoinHandle<()>>> {
+    let exists = Path::new(VM_INFORMANT_PATH)
+        .try_exists()
+        .context("could not check if path exists")?;
+
+    if !exists {
+        return Ok(None);
+    }
+
+    Ok(Some(
+        thread::Builder::new()
+            .name("run-vm-informant".into())
+            .spawn(move || run_informant())?,
+    ))
+}
+
+fn run_informant() -> ! {
+    let restart_wait = Duration::from_millis(RESTART_INFORMANT_AFTER_MILLIS);
+
+    info!("starting VM informant");
+
+    loop {
+        let mut cmd = process::Command::new(VM_INFORMANT_PATH);
+        // Block on subprocess:
+        let result = cmd.status();
+
+        match result {
+            Err(e) => warn!("failed to run VM informant at {VM_INFORMANT_PATH:?}: {e}"),
+            Ok(status) if !status.success() => {
+                warn!("{VM_INFORMANT_PATH} exited with code {status:?}, retrying")
+            }
+            Ok(_) => info!("{VM_INFORMANT_PATH} ended gracefully (unexpectedly). Retrying"),
+        }
+
+        // Wait before retrying
+        thread::sleep(restart_wait);
+    }
+}

compute_tools/src/lib.rs

@@ -8,6 +8,7 @@ pub mod http;
 #[macro_use]
 pub mod logger;
 pub mod compute;
+pub mod informant;
 pub mod monitor;
 pub mod params;
 pub mod pg_helpers;

compute_tools/src/logger.rs

@@ -1,43 +1,37 @@
-use std::io::Write;
+use tracing_opentelemetry::OpenTelemetryLayer;
+use tracing_subscriber::layer::SubscriberExt;
+use tracing_subscriber::prelude::*;
 
-use anyhow::Result;
-use chrono::Utc;
-use env_logger::{Builder, Env};
-
-macro_rules! info_println {
-    ($($tts:tt)*) => {
-        if log_enabled!(Level::Info) {
-            println!($($tts)*);
-        }
-    }
-}
-
-macro_rules! info_print {
-    ($($tts:tt)*) => {
-        if log_enabled!(Level::Info) {
-            print!($($tts)*);
-        }
-    }
-}
-
-/// Initialize `env_logger` using either `default_level` or
+/// Initialize logging to stderr, and OpenTelemetry tracing and exporter.
+///
+/// Logging is configured using either `default_log_level` or
 /// `RUST_LOG` environment variable as default log level.
-pub fn init_logger(default_level: &str) -> Result<()> {
-    let env = Env::default().filter_or("RUST_LOG", default_level);
+///
+/// OpenTelemetry is configured with OTLP/HTTP exporter. It picks up
+/// configuration from environment variables. For example, to change the destination,
+/// set `OTEL_EXPORTER_OTLP_ENDPOINT=http://jaeger:4318`. See
+/// `tracing-utils` package description.
+///
+pub fn init_tracing_and_logging(default_log_level: &str) -> anyhow::Result<()> {
+    // Initialize Logging
+    let env_filter = tracing_subscriber::EnvFilter::try_from_default_env()
+        .unwrap_or_else(|_| tracing_subscriber::EnvFilter::new(default_log_level));
 
-    Builder::from_env(env)
-        .format(|buf, record| {
-            let thread_handle = std::thread::current();
-            writeln!(
-                buf,
-                "{} [{}] {}: {}",
-                Utc::now().format("%Y-%m-%d %H:%M:%S%.3f %Z"),
-                thread_handle.name().unwrap_or("main"),
-                record.level(),
-                record.args()
-            )
-        })
+    let fmt_layer = tracing_subscriber::fmt::layer()
+        .with_target(false)
+        .with_writer(std::io::stderr);
+
+    // Initialize OpenTelemetry
+    let otlp_layer =
+        tracing_utils::init_tracing_without_runtime("compute_ctl").map(OpenTelemetryLayer::new);
+
+    // Put it all together
+    tracing_subscriber::registry()
+        .with(env_filter)
+        .with(otlp_layer)
+        .with(fmt_layer)
         .init();
+    tracing::info!("logging and tracing started");
 
     Ok(())
 }

compute_tools/src/monitor.rs

@@ -3,8 +3,8 @@ use std::{thread, time};
 
 use anyhow::Result;
 use chrono::{DateTime, Utc};
-use log::{debug, info};
 use postgres::{Client, NoTls};
+use tracing::{debug, info};
 
 use crate::compute::ComputeNode;
 

compute_tools/src/params.rs

@@ -1,3 +1,9 @@
 pub const DEFAULT_LOG_LEVEL: &str = "info";
-pub const DEFAULT_CONNSTRING: &str = "host=localhost user=postgres";
+// From Postgres docs:
+//   To ease transition from the md5 method to the newer SCRAM method, if md5 is specified
+//   as a method in pg_hba.conf but the user's password on the server is encrypted for SCRAM
+//   (see below), then SCRAM-based authentication will automatically be chosen instead.
+//   https://www.postgresql.org/docs/15/auth-password.html
+//
+// So it's safe to set md5 here, as `control-plane` anyway uses SCRAM for all roles.
 pub const PG_HBA_ALL_MD5: &str = "host\tall\t\tall\t\t0.0.0.0/0\t\tmd5";

compute_tools/src/pg_helpers.rs

@@ -11,6 +11,7 @@ use anyhow::{bail, Result};
 use notify::{RecursiveMode, Watcher};
 use postgres::{Client, Transaction};
 use serde::Deserialize;
+use tracing::{debug, instrument};
 
 const POSTGRES_WAIT_TIMEOUT: Duration = Duration::from_millis(60 * 1000); // milliseconds
 
@@ -129,8 +130,8 @@ impl Role {
     /// Serialize a list of role parameters into a Postgres-acceptable
     /// string of arguments.
     pub fn to_pg_options(&self) -> String {
-        // XXX: consider putting LOGIN as a default option somewhere higher, e.g. in Rails.
-        // For now we do not use generic `options` for roles. Once used, add
+        // XXX: consider putting LOGIN as a default option somewhere higher, e.g. in control-plane.
+        // For now, we do not use generic `options` for roles. Once used, add
         // `self.options.as_pg_options()` somewhere here.
         let mut params: String = "LOGIN".to_string();
 
@@ -229,6 +230,7 @@ pub fn get_existing_dbs(client: &mut Client) -> Result<Vec<Database>> {
 /// Wait for Postgres to become ready to accept connections. It's ready to
 /// accept connections when the state-field in `pgdata/postmaster.pid` says
 /// 'ready'.
+#[instrument(skip(pg))]
 pub fn wait_for_postgres(pg: &mut Child, pgdata: &Path) -> Result<()> {
     let pid_path = pgdata.join("postmaster.pid");
 
@@ -287,18 +289,18 @@ pub fn wait_for_postgres(pg: &mut Child, pgdata: &Path) -> Result<()> {
         }
 
         let res = rx.recv_timeout(Duration::from_millis(100));
-        log::debug!("woken up by notify: {res:?}");
+        debug!("woken up by notify: {res:?}");
         // If there are multiple events in the channel already, we only need to be
         // check once. Swallow the extra events before we go ahead to check the
         // pid file.
         while let Ok(res) = rx.try_recv() {
-            log::debug!("swallowing extra event: {res:?}");
+            debug!("swallowing extra event: {res:?}");
         }
 
         // Check that we can open pid file first.
         if let Ok(file) = File::open(&pid_path) {
             if !postmaster_pid_seen {
-                log::debug!("postmaster.pid appeared");
+                debug!("postmaster.pid appeared");
                 watcher
                     .unwatch(pgdata)
                     .expect("Failed to remove pgdata dir watch");
@@ -314,7 +316,7 @@ pub fn wait_for_postgres(pg: &mut Child, pgdata: &Path) -> Result<()> {
             // Pid file could be there and we could read it, but it could be empty, for example.
             if let Some(Ok(line)) = last_line {
                 let status = line.trim();
-                log::debug!("last line of postmaster.pid: {status:?}");
+                debug!("last line of postmaster.pid: {status:?}");
 
                 // Now Postgres is ready to accept connections
                 if status == "ready" {
@@ -330,7 +332,7 @@ pub fn wait_for_postgres(pg: &mut Child, pgdata: &Path) -> Result<()> {
         }
     }
 
-    log::info!("PostgreSQL is now running, continuing to configure it");
+    tracing::info!("PostgreSQL is now running, continuing to configure it");
 
     Ok(())
 }

compute_tools/src/spec.rs

@@ -1,12 +1,12 @@
+use std::collections::HashMap;
 use std::path::Path;
 use std::str::FromStr;
-use std::time::Instant;
 
 use anyhow::Result;
-use log::{info, log_enabled, warn, Level};
 use postgres::config::Config;
 use postgres::{Client, NoTls};
 use serde::Deserialize;
+use tracing::{info, info_span, instrument, span_enabled, warn, Level};
 
 use crate::compute::ComputeNode;
 use crate::config;
@@ -23,6 +23,8 @@ pub struct ComputeSpec {
     /// Expected cluster state at the end of transition process.
     pub cluster: Cluster,
     pub delta_operations: Option<Vec<DeltaOp>>,
+
+    pub startup_tracing_context: Option<HashMap<String, String>>,
 }
 
 /// Cluster state seen from the perspective of the external tools
@@ -80,23 +82,25 @@ pub fn update_pg_hba(pgdata_path: &Path) -> Result<()> {
 
 /// Given a cluster spec json and open transaction it handles roles creation,
 /// deletion and update.
+#[instrument(skip_all)]
 pub fn handle_roles(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
     let mut xact = client.transaction()?;
     let existing_roles: Vec<Role> = get_existing_roles(&mut xact)?;
 
     // Print a list of existing Postgres roles (only in debug mode)
-    info!("postgres roles:");
-    for r in &existing_roles {
-        info_println!(
-            "{} - {}:{}",
-            " ".repeat(27 + 5),
-            r.name,
-            if r.encrypted_password.is_some() {
-                "[FILTERED]"
-            } else {
-                "(null)"
-            }
-        );
+    if span_enabled!(Level::INFO) {
+        info!("postgres roles:");
+        for r in &existing_roles {
+            info!(
+                "    - {}:{}",
+                r.name,
+                if r.encrypted_password.is_some() {
+                    "[FILTERED]"
+                } else {
+                    "(null)"
+                }
+            );
+        }
     }
 
     // Process delta operations first
@@ -137,58 +141,80 @@ pub fn handle_roles(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
     info!("cluster spec roles:");
     for role in &spec.cluster.roles {
         let name = &role.name;
-
-        info_print!(
-            "{} - {}:{}",
-            " ".repeat(27 + 5),
-            name,
-            if role.encrypted_password.is_some() {
-                "[FILTERED]"
-            } else {
-                "(null)"
-            }
-        );
-
         // XXX: with a limited number of roles it is fine, but consider making it a HashMap
         let pg_role = existing_roles.iter().find(|r| r.name == *name);
 
-        if let Some(r) = pg_role {
-            let mut update_role = false;
-
+        enum RoleAction {
+            None,
+            Update,
+            Create,
+        }
+        let action = if let Some(r) = pg_role {
             if (r.encrypted_password.is_none() && role.encrypted_password.is_some())
                 || (r.encrypted_password.is_some() && role.encrypted_password.is_none())
             {
-                update_role = true;
+                RoleAction::Update
             } else if let Some(pg_pwd) = &r.encrypted_password {
-                // Check whether password changed or not (trim 'md5:' prefix first)
-                update_role = pg_pwd[3..] != *role.encrypted_password.as_ref().unwrap();
+                // Check whether password changed or not (trim 'md5' prefix first if any)
+                //
+                // This is a backward compatibility hack, which comes from the times when we were using
+                // md5 for everyone and hashes were stored in the console db without md5 prefix. So when
+                // role comes from the control-plane (json spec) `Role.encrypted_password` doesn't have md5 prefix,
+                // but when role comes from Postgres (`get_existing_roles` / `existing_roles`) it has this prefix.
+                // Here is the only place so far where we compare hashes, so it seems to be the best candidate
+                // to place this compatibility layer.
+                let pg_pwd = if let Some(stripped) = pg_pwd.strip_prefix("md5") {
+                    stripped
+                } else {
+                    pg_pwd
+                };
+                if pg_pwd != *role.encrypted_password.as_ref().unwrap() {
+                    RoleAction::Update
+                } else {
+                    RoleAction::None
+                }
+            } else {
+                RoleAction::None
             }
+        } else {
+            RoleAction::Create
+        };
 
-            if update_role {
+        match action {
+            RoleAction::None => {}
+            RoleAction::Update => {
                 let mut query: String = format!("ALTER ROLE {} ", name.pg_quote());
-                info_print!(" -> update");
-
                 query.push_str(&role.to_pg_options());
                 xact.execute(query.as_str(), &[])?;
             }
-        } else {
-            info!("role name: '{}'", &name);
-            let mut query: String = format!("CREATE ROLE {} ", name.pg_quote());
-            info!("role create query: '{}'", &query);
-            info_print!(" -> create");
+            RoleAction::Create => {
+                let mut query: String = format!("CREATE ROLE {} ", name.pg_quote());
+                info!("role create query: '{}'", &query);
+                query.push_str(&role.to_pg_options());
+                xact.execute(query.as_str(), &[])?;
 
-            query.push_str(&role.to_pg_options());
-            xact.execute(query.as_str(), &[])?;
-
-            let grant_query = format!(
-                "GRANT pg_read_all_data, pg_write_all_data TO {}",
-                name.pg_quote()
-            );
-            xact.execute(grant_query.as_str(), &[])?;
-            info!("role grant query: '{}'", &grant_query);
+                let grant_query = format!(
+                    "GRANT pg_read_all_data, pg_write_all_data TO {}",
+                    name.pg_quote()
+                );
+                xact.execute(grant_query.as_str(), &[])?;
+                info!("role grant query: '{}'", &grant_query);
+            }
         }
 
-        info_print!("\n");
+        if span_enabled!(Level::INFO) {
+            let pwd = if role.encrypted_password.is_some() {
+                "[FILTERED]"
+            } else {
+                "(null)"
+            };
+            let action_str = match action {
+                RoleAction::None => "",
+                RoleAction::Create => " -> create",
+                RoleAction::Update => " -> update",
+            };
+            info!("   - {}:{}{}", name, pwd, action_str);
+        }
     }
 
     xact.commit()?;
@@ -197,12 +223,25 @@ pub fn handle_roles(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
 }
 
 /// Reassign all dependent objects and delete requested roles.
+#[instrument(skip_all)]
 pub fn handle_role_deletions(node: &ComputeNode, client: &mut Client) -> Result<()> {
     if let Some(ops) = &node.spec.delta_operations {
         // First, reassign all dependent objects to db owners.
         info!("reassigning dependent objects of to-be-deleted roles");
+
+        // Fetch existing roles. We could've exported and used `existing_roles` from
+        // `handle_roles()`, but we only make this list there before creating new roles.
+        // Which is probably fine as we never create to-be-deleted roles, but that'd
+        // just look a bit untidy. Anyway, the entire `pg_roles` should be in shared
+        // buffers already, so this shouldn't be a big deal.
+        let mut xact = client.transaction()?;
+        let existing_roles: Vec<Role> = get_existing_roles(&mut xact)?;
+        xact.commit()?;
+
         for op in ops {
-            if op.action == "delete_role" {
+            // Check that role is still present in Postgres, as this could be a
+            // restart with the same spec after role deletion.
+            if op.action == "delete_role" && existing_roles.iter().any(|r| r.name == op.name) {
                 reassign_owned_objects(node, &op.name)?;
             }
         }
@@ -261,13 +300,16 @@ fn reassign_owned_objects(node: &ComputeNode, role_name: &PgIdent) -> Result<()>
 /// like `CREATE DATABASE` and `DROP DATABASE` do not support it. Statement-level
 /// atomicity should be enough here due to the order of operations and various checks,
 /// which together provide us idempotency.
+#[instrument(skip_all)]
 pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
     let existing_dbs: Vec<Database> = get_existing_dbs(client)?;
 
     // Print a list of existing Postgres databases (only in debug mode)
-    info!("postgres databases:");
-    for r in &existing_dbs {
-        info_println!("{} - {}:{}", " ".repeat(27 + 5), r.name, r.owner);
+    if span_enabled!(Level::INFO) {
+        info!("postgres databases:");
+        for r in &existing_dbs {
+            info!("    {}:{}", r.name, r.owner);
+        }
     }
 
     // Process delta operations first
@@ -310,13 +352,15 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
     for db in &spec.cluster.databases {
         let name = &db.name;
 
-        info_print!("{} - {}:{}", " ".repeat(27 + 5), db.name, db.owner);
-
         // XXX: with a limited number of databases it is fine, but consider making it a HashMap
         let pg_db = existing_dbs.iter().find(|r| r.name == *name);
 
-        let start_time = Instant::now();
-        if let Some(r) = pg_db {
+        enum DatabaseAction {
+            None,
+            Update,
+            Create,
+        }
+        let action = if let Some(r) = pg_db {
             // XXX: db owner name is returned as quoted string from Postgres,
             // when quoting is needed.
             let new_owner = if r.owner.starts_with('"') {
@@ -326,29 +370,42 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
             };
 
             if new_owner != r.owner {
+                // Update the owner
+                DatabaseAction::Update
+            } else {
+                DatabaseAction::None
+            }
+        } else {
+            DatabaseAction::Create
+        };
+
+        match action {
+            DatabaseAction::None => {}
+            DatabaseAction::Update => {
                 let query: String = format!(
                     "ALTER DATABASE {} OWNER TO {}",
                     name.pg_quote(),
                     db.owner.pg_quote()
                 );
-                info_print!(" -> update");
-
+                let _ = info_span!("executing", query).entered();
                 client.execute(query.as_str(), &[])?;
-                let elapsed = start_time.elapsed().as_millis();
-                info_print!(" ({} ms)", elapsed);
             }
-        } else {
-            let mut query: String = format!("CREATE DATABASE {} ", name.pg_quote());
-            info_print!(" -> create");
+            DatabaseAction::Create => {
+                let mut query: String = format!("CREATE DATABASE {} ", name.pg_quote());
+                query.push_str(&db.to_pg_options());
+                let _ = info_span!("executing", query).entered();
+                client.execute(query.as_str(), &[])?;
+            }
+        };
 
-            query.push_str(&db.to_pg_options());
-            client.execute(query.as_str(), &[])?;
-
-            let elapsed = start_time.elapsed().as_millis();
-            info_print!(" ({} ms)", elapsed);
+        if span_enabled!(Level::INFO) {
+            let action_str = match action {
+                DatabaseAction::None => "",
+                DatabaseAction::Create => " -> create",
+                DatabaseAction::Update => " -> update",
+            };
+            info!("   - {}:{}{}", db.name, db.owner, action_str);
         }
-
-        info_print!("\n");
     }
 
     Ok(())
@@ -356,6 +413,7 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
 
 /// Grant CREATE ON DATABASE to the database owner and do some other alters and grants
 /// to allow users creating trusted extensions and re-creating `public` schema, for example.
+#[instrument(skip_all)]
 pub fn handle_grants(node: &ComputeNode, client: &mut Client) -> Result<()> {
     let spec = &node.spec;
 

control_plane/Cargo.toml

@@ -1,32 +1,31 @@
 [package]
 name = "control_plane"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = "1.0"
-clap = "4.0"
-comfy-table = "6.1"
-git-version = "0.3.5"
-nix = "0.25"
-once_cell = "1.13.0"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev = "43e6db254a97fdecbce33d8bc0890accfd74495e" }
-regex = "1"
-reqwest = { version = "0.11", default-features = false, features = ["blocking", "json", "rustls-tls"] }
-serde = { version = "1.0", features = ["derive"] }
-serde_with = "2.0"
-tar = "0.4.38"
-thiserror = "1"
-toml = "0.5"
-url = "2.2.2"
-
+anyhow.workspace = true
+clap.workspace = true
+comfy-table.workspace = true
+git-version.workspace = true
+nix.workspace = true
+once_cell.workspace = true
+postgres.workspace = true
+regex.workspace = true
+reqwest = { workspace = true, features = ["blocking", "json"] }
+serde.workspace = true
+serde_with.workspace = true
+tar.workspace = true
+thiserror.workspace = true
+toml.workspace = true
+url.workspace = true
 # Note: Do not directly depend on pageserver or safekeeper; use pageserver_api or safekeeper_api
 # instead, so that recompile times are better.
-pageserver_api = { path = "../libs/pageserver_api" }
-postgres_connection = { path = "../libs/postgres_connection" }
-safekeeper_api = { path = "../libs/safekeeper_api" }
-# Note: main broker code is inside the binary crate, so linking with the library shouldn't be heavy.
-storage_broker = { version = "0.1", path = "../storage_broker" }
-utils = { path = "../libs/utils" }
-workspace_hack = { version = "0.1", path = "../workspace_hack" }
+pageserver_api.workspace = true
+safekeeper_api.workspace = true
+postgres_connection.workspace = true
+storage_broker.workspace = true
+utils.workspace = true
+
+workspace_hack.workspace = true

deny.toml

@@ -52,7 +52,7 @@ name = "ring"
 version = "*"
 expression = "MIT AND ISC AND OpenSSL"
 license-files = [
-    { path = "LICENSE", hash = 0xbd0eed23 },
+    { path = "LICENSE", hash = 0xbd0eed23 }
 ]
 
 [licenses.private]

docs/consumption_metrics.md

@@ -0,0 +1,115 @@
+### Overview
+Pageserver and proxy periodically collect consumption metrics and push them to a HTTP endpoint.
+
+This doc describes current implementation details.
+For design details see [the RFC](./rfcs/021-metering.md) and [the discussion on Github](https://github.com/neondatabase/neon/pull/2884).
+
+- The metrics are collected in a separate thread, and the collection interval and endpoint are configurable.
+
+- Metrics are cached, so that we don't send unchanged metrics on every iteration.
+
+- Metrics are sent in batches of 1000 (see CHUNK_SIZE const) metrics max with no particular grouping guarantees.
+
+batch format is
+```json
+
+{ "events" : [metric1, metric2, ...]]}
+
+```
+See metric format examples below.
+
+- All metrics values are in bytes, unless otherwise specified.
+
+- Currently no retries are implemented.
+
+### Pageserver metrics
+
+#### Configuration
+The endpoint and the collection interval are specified in the pageserver config file (or can be passed as command line arguments):
+`metric_collection_endpoint` defaults to None, which means that metric collection is disabled by default.
+`metric_collection_interval` defaults to 10min
+
+#### Metrics
+
+Currently, the following metrics are collected:
+
+- `written_size`
+
+Amount of WAL produced , by a timeline, i.e. last_record_lsn
+This is an absolute, per-timeline metric.
+
+- `resident_size`
+
+Size of all the layer files in the tenant's directory on disk on the pageserver.
+This is an absolute, per-tenant metric.
+
+- `remote_storage_size`
+
+Size of the remote storage (S3) directory.
+This is an absolute, per-tenant metric.
+
+- `timeline_logical_size`
+Logical size of the data in the timeline
+This is an absolute, per-timeline metric.
+
+- `synthetic_storage_size`
+Size of all tenant's branches including WAL
+This is the same metric that `tenant/{tenant_id}/size` endpoint returns.
+This is an absolute, per-tenant metric.
+
+Synthetic storage size is calculated in a separate thread, so it might be slightly outdated.
+
+#### Format example
+
+```json
+{
+"metric": "remote_storage_size",
+"type": "absolute",
+"time": "2022-12-28T11:07:19.317310284Z",
+"idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
+"value": 12345454,
+"tenant_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
+"timeline_id": "a03ebb4f5922a1c56ff7485cc8854143",
+}
+```
+
+`idempotency_key` is a unique key for each metric, so that we can deduplicate metrics.
+It is a combination of the time, node_id and a random number.
+
+### Proxy consumption metrics
+
+#### Configuration
+The endpoint and the collection interval can be passed as command line arguments for proxy:
+`metric_collection_endpoint` no default, which means that metric collection is disabled by default.
+`metric_collection_interval` no default
+
+#### Metrics
+
+Currently, only one proxy metric is collected:
+
+- `proxy_io_bytes_per_client`
+Outbound traffic per client.
+This is an incremental, per-endpoint metric.
+
+#### Format example
+
+```json
+{
+"metric": "proxy_io_bytes_per_client",
+"type": "incremental",
+"start_time": "2022-12-28T11:07:19.317310284Z",
+"stop_time": "2022-12-28T11:07:19.317310284Z",
+"idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
+"value": 12345454,
+"endpoint_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
+}
+```
+
+The metric is incremental, so the value is the difference between the current and the previous value.
+If there is no previous value, the value, the value is the current value and the `start_time` equals `stop_time`.
+
+### TODO
+
+- [ ] Handle errors better: currently if one tenant fails to gather metrics, the whole iteration fails and metrics are not sent for any tenant.
+- [ ] Add retries
+- [ ] Tune the interval

docs/rfcs/021-metering.md

@@ -0,0 +1,186 @@
+# Consumption tracking
+
+
+# Goals
+
+This proposal is made with two mostly but not entirely overlapping goals:
+
+* Collect info that is needed for consumption-based billing
+* Cross-check AWS bills
+
+
+# Metrics
+
+There are six metrics to collect:
+
+* CPU time. Wall clock seconds * the current number of cores. We have a fixed ratio of memory to cores, so the current memory size is the function of the number of cores. Measured per each `endpoint`.
+
+* Traffic. In/out traffic on the proxy. Measured per each `endpoint`.
+
+* Written size. Amount of data we write. That is different from both traffic and storage size, as only during the writing we
+
+  a) occupy some disk bandwidth on safekeepers
+
+  b) necessarily cross AZ boundaries delivering WAL to all safekeepers
+
+  Each timeline/branch has at most one writer, so the data is collected per branch.
+
+* Synthetic storage size. That is what is exposed now with pageserver's `/v1/tenant/{}/size`. Looks like now it is per-tenant. (Side note: can we make it per branch to show as branch physical size in UI?)
+
+* Real storage size. That is the size of the tenant directory on the pageservers disk. Per-tenant.
+
+* S3 storage size. That is the size of the tenant data on S3. Per-tenant.
+
+That info should be enough to build an internal model that predicts AWS price (hence tracking `written data` and `real storage size`). As for the billing model we probably can get away with mentioning only `CPU time`, `synthetic storage size`, and `traffic` consumption.
+
+# Services participating in metrics collection
+
+## Proxy
+
+For actual implementation details check `/docs/consumption_metrics.md`
+
+Proxy is the only place that knows about traffic flow, so it tracks it and reports it with quite a small interval, let's say 1 minute. A small interval is needed here since the proxy is stateless, and any restart will reset accumulated consumption. Also proxy should report deltas since the last report, not an absolute value of the counter. Such kind of events is easier to integrate over a period of time to get the amount of traffic during some time interval.
+
+Example event:
+
+```json
+{
+"metric": "proxy_io_bytes_per_client",
+"type": "incremental",
+"start_time": "2022-12-28T11:07:19.317310284Z",
+"stop_time": "2022-12-28T11:07:19.317310284Z",
+"idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
+"value": 12345454,
+"endpoint_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
+}
+```
+
+Since we report deltas over some period of time, it makes sense to include `event_start_time`/`event_stop_time` where `event_start_time` is the time of the previous report. That will allow us to identify metering gaps better (e.g., failed send/delivery).
+
+When there is no active connection proxy can avoid reporting anything. Also, deltas are additive, so several console instances serving the same user and endpoint can report traffic without coordination.
+
+## Console
+
+The console knows about start/stop events, so it knows the amount of CPU time allocated to each endpoint. It also knows about operation successes and failures and can avoid billing clients after unsuccessful 'suspend' events. The console doesn't know the current compute size within the allowed limits on the endpoint. So with CPU time, we do the following:
+
+* While we don't yet have the autoscaling console can report `cpu time` as the number of seconds since the last `start_compute` event.
+
+* When we have autoscaling, `autoscaler-agent` can report `cpu time`*`compute_units_count` in the same increments as the proxy reports traffic.
+
+Example event:
+
+```json
+{
+    "metric": "effective_compute_seconds",
+    "type": "increment",
+    "endpoint_id": "blazing-warrior-34",
+    "event_start_time": ...,
+    "event_stop_time": ...,
+    "value": 12345454,
+}
+```
+
+I'd also suggest reporting one value, `cpu time`*`compute_units_count`, instead of two separate fields as it makes event schema simpler (it is possible to treat it the same way as traffic) and preserves additivity.
+
+## Pageserver
+
+For actual implementation details check `/docs/consumption_metrics.md`
+
+Pageserver knows / has access to / can calculate the rest of the metrics:
+
+* Written size -- that is basically `last_received_lsn`,
+* Synthetic storage size -- there is a way to calculate it, albeit a costly one,
+* Real storage size -- there is a way to calculate it using a layer map or filesystem,
+* S3 storage size -- can calculate it by S3 API calls
+
+Some of those metrics are expensive to calculate, so the reporting period here is driven mainly by implementation details. We can set it to, for example, once per hour. Not a big deal since the pageserver is stateful, and all metrics can be reported as an absolute value, not increments. At the same time, a smaller reporting period improves UX, so it would be good to have something more real-time.
+
+`written size` is primarily a safekeeper-related metric, but since it is available on both pageserver and safekeeper, we can avoid reporting anything from the safekeeper.
+
+Example event:
+
+```json
+{
+"metric": "remote_storage_size",
+"type": "absolute",
+"time": "2022-12-28T11:07:19.317310284Z",
+"idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
+"value": 12345454,
+"tenant_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
+"timeline_id": "a03ebb4f5922a1c56ff7485cc8854143",
+}
+```
+
+# Data collection
+
+## Push vs. pull
+
+We already have pull-based Prometheus metrics, so it is tempting to use them here too. However, in our setup, it is hard to tell when some metric changes. For example, garbage collection will constantly free some disk space over a week, even if the project is down for that week. We could also iterate through all existing tenants/branches/endpoints, but that means some amount of code to do that properly and most likely we will end up with some per-metric hacks in the collector to cut out some of the tenants that are surely not changing that metric.
+
+With the push model, it is easier to publish data only about actively changing metrics -- pageserver knows when it performs s3 offloads, garbage collection and starts/stops consuming data from the safekeeper; proxy knows about connected clients; console / autoscaler-agent knows about active cpu time.
+
+Hence, let's go with a push-based model.
+
+## Common bus vs. proxying through the console
+
+We can implement such push systems in a few ways:
+
+a. Each component pushes its metrics to the "common bus", namely segment, Kafka, or something similar. That approach scales well, but it would be harder to test it locally, will introduce new dependencies, we will have to distribute secrets for that connection to all of the components, etc. We would also have to loop back some of the events and their aggregates to the console, as we want to show some that metrics to the user in real-time.
+
+b. Each component can call HTTP `POST` with its events to the console, and the console can forward it to the segment for later integration with metronome / orb / onebill / etc. With that approach, only the console has to speak with segment. Also since that data passes through the console, the console can save the latest metrics values, so there is no need for constant feedback of that events back from the segment.
+
+# Implementation
+
+Each (proxy|pageserver|autoscaler-agent) sends consumption events to the single endpoint in the console:
+
+```json
+POST /usage_events HTTP/1.1
+Content-Type: application/json
+
+[
+{
+"metric": "remote_storage_size",
+"type": "absolute",
+"time": "2022-12-28T11:07:19.317310284Z",
+"idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
+"value": 12345454,
+"tenant_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
+"timeline_id": "a03ebb4f5922a1c56ff7485cc8854143",
+},
+...
+]
+```
+
+![data flow](./images/metering.jpg)
+
+Events could be either:
+* `incremental` -- change in consumption since the previous event or service restart. That is `effective_cpu_seconds`, `traffic_in_bytes`, and `traffic_out_bytes`.
+* `absolute` -- that is the current value of a metric. All of the size-related metrics are absolute.
+
+Each service can post events at its own pace and bundle together data from different tenants/endpoints.
+
+The console algorithm upon receive of events could be the following:
+
+1. Create and send a segment event with the same content (possibly enriching it with tenant/timeline data for endpoint-based events).
+2. Update the latest state of per-tenant and per-endpoint metrics in the database.
+3. Check whether any of that metrics is above the allowed threshold and stop the project if necessary.
+
+Since all the data comes in batches, we can do the batch update to reduce the number of queries in the database. Proxy traffic is probably the most frequent metric, so with batching, we will have extra `number_of_proxies` requests to the database each minute. This is most likely fine for now but will generate many dead tuples in the console database. If that is the case, we can change step 2 to the following:
+
+2.1. Check if there $tenant_$metric / $endpoint_$metric key in Redis
+
+2.2. If no stored value is found and the metric is incremental, then fetch the current value from DWH (which keeps aggregated value for all the events) and publish it.
+
+2.3. Publish a new value (absolute metric) or add an increment to the stored value (incremental metric)
+
+## Consumption watchdog
+
+Since all the data goes through the console, we don't have to run any background thread/coroutines to check whether consumption is within the allowed limits. We only change consumption with `POST /usage_events`, so limit checks could be applied in the same handler.
+
+## Extensibility
+
+If we need to add a new metric (e.g. s3 traffic or something else), the console code should, by default, process it and publish segment event, even if the metric name is unknown to the console.
+
+## Naming & schema
+
+Each metric name should end up with units -- now `_seconds` and `_bytes`, and segment event should always have `tenant_id` and `timeline_id`/`endpoint_id` where applicable.

docs/sourcetree.md

@@ -18,10 +18,6 @@ Intended to be used in integration tests and in CLI tools for local installation
 Documentation of the Neon features and concepts.
 Now it is mostly dev documentation.
 
-`/monitoring`:
-
-TODO
-
 `/pageserver`:
 
 Neon storage service.
@@ -98,6 +94,13 @@ cargo hakari manage-deps
 
 If you don't have hakari installed (`error: no such subcommand: hakari`), install it by running `cargo install cargo-hakari`.
 
+### Checking Rust 3rd-parties
+[Cargo deny](https://embarkstudios.github.io/cargo-deny/index.html) is a cargo plugin that lets us lint project's dependency graph to ensure all dependencies conform to requirements. It detects security issues, matches licenses, and ensures crates only come from trusted sources.
+
+```bash
+cargo deny check
+```
+
 ## Using Python
 Note that Debian/Ubuntu Python packages are stale, as it commonly happens,
 so manual installation of dependencies is not recommended.

libs/consumption_metrics/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "consumption_metrics"
+version = "0.1.0"
+edition = "2021"
+license = "Apache-2.0"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+anyhow = "1.0.68"
+chrono = { version = "0.4", default-features = false, features = ["clock", "serde"] }
+rand = "0.8.3"
+serde = "1.0.152"
+serde_with = "2.1.0"
+utils = { version = "0.1.0", path = "../utils" }
+workspace_hack = { version = "0.1.0", path = "../../workspace_hack" }

libs/consumption_metrics/src/lib.rs

@@ -0,0 +1,50 @@
+//!
+//! Shared code for consumption metics collection
+//!
+use chrono::{DateTime, Utc};
+use rand::Rng;
+use serde::Serialize;
+
+#[derive(Serialize, Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
+#[serde(tag = "type")]
+pub enum EventType {
+    #[serde(rename = "absolute")]
+    Absolute { time: DateTime<Utc> },
+    #[serde(rename = "incremental")]
+    Incremental {
+        start_time: DateTime<Utc>,
+        stop_time: DateTime<Utc>,
+    },
+}
+
+#[derive(Serialize, Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
+pub struct Event<Extra> {
+    #[serde(flatten)]
+    #[serde(rename = "type")]
+    pub kind: EventType,
+
+    pub metric: &'static str,
+    pub idempotency_key: String,
+    pub value: u64,
+
+    #[serde(flatten)]
+    pub extra: Extra,
+}
+
+pub fn idempotency_key(node_id: String) -> String {
+    format!(
+        "{}-{}-{:04}",
+        Utc::now(),
+        node_id,
+        rand::thread_rng().gen_range(0..=9999)
+    )
+}
+
+pub const CHUNK_SIZE: usize = 1000;
+
+// Just a wrapper around a slice of events
+// to serialize it as `{"events" : [ ] }
+#[derive(serde::Serialize)]
+pub struct EventChunk<'a, T> {
+    pub events: &'a [T],
+}

libs/metrics/Cargo.toml

@@ -1,11 +1,12 @@
 [package]
 name = "metrics"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-prometheus = {version = "0.13", default_features=false, features = ["process"]} # removes protobuf dependency
-libc = "0.2"
-once_cell = "1.13.0"
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+prometheus.workspace = true
+libc.workspace = true
+once_cell.workspace = true
+
+workspace_hack.workspace = true

libs/pageserver_api/Cargo.toml

@@ -1,17 +1,17 @@
 [package]
 name = "pageserver_api"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-serde = { version = "1.0", features = ["derive"] }
-serde_with = "2.0"
-const_format = "0.2.21"
-anyhow = { version = "1.0", features = ["backtrace"] }
-bytes = "1.0.1"
-byteorder = "1.4.3"
+serde.workspace = true
+serde_with.workspace = true
+const_format.workspace = true
+anyhow.workspace = true
+bytes.workspace = true
+byteorder.workspace = true
+utils.workspace = true
+postgres_ffi.workspace = true
 
-utils = { path = "../utils" }
-postgres_ffi = { path = "../postgres_ffi" }
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+workspace_hack.workspace = true

libs/pageserver_api/src/models.rs

@@ -1,4 +1,4 @@
-use std::num::NonZeroU64;
+use std::num::{NonZeroU64, NonZeroUsize};
 
 use byteorder::{BigEndian, ReadBytesExt};
 use serde::{Deserialize, Serialize};
@@ -44,18 +44,17 @@ impl TenantState {
 /// A state of a timeline in pageserver's memory.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 pub enum TimelineState {
-    /// Timeline is fully operational. If the containing Tenant is Active, the timeline's
-    /// background jobs are running otherwise they will be launched when the tenant is activated.
+    /// The timeline is recognized by the pageserver but is not yet operational.
+    /// In particular, the walreceiver connection loop is not running for this timeline.
+    /// It will eventually transition to state Active or Broken.
+    Loading,
+    /// The timeline is fully operational.
+    /// It can be queried, and the walreceiver connection loop is running.
     Active,
-    /// A timeline is recognized by pageserver, but not yet ready to operate.
-    /// The status indicates, that the timeline could eventually go back to Active automatically:
-    /// for example, if the owning tenant goes back to Active again.
-    Suspended,
-    /// A timeline is recognized by pageserver, but not yet ready to operate and not allowed to
-    /// automatically become Active after certain events: only a management call can change this status.
+    /// The timeline was previously Loading or Active but is shutting down.
+    /// It cannot transition back into any other state.
     Stopping,
-    /// A timeline is recognized by the pageserver, but can no longer be used for
-    /// any operations, because it failed to be activated.
+    /// The timeline is broken and not operational (previous states: Loading or Active).
     Broken,
 }
 
@@ -210,6 +209,11 @@ pub struct TimelineInfo {
     pub state: TimelineState,
 }
 
+#[derive(Debug, Serialize, Deserialize)]
+pub struct DownloadRemoteLayersTaskSpawnRequest {
+    pub max_concurrent_downloads: NonZeroUsize,
+}
+
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub struct DownloadRemoteLayersTaskInfo {
     pub task_id: String,

libs/postgres_connection/Cargo.toml

@@ -1,18 +1,17 @@
 [package]
 name = "postgres_connection"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = "1.0"
-itertools = "0.10.3"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev = "43e6db254a97fdecbce33d8bc0890accfd74495e" }
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-url = "2.2.2"
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+anyhow.workspace = true
+itertools.workspace = true
+postgres.workspace = true
+tokio-postgres.workspace = true
+url.workspace = true
+
+workspace_hack.workspace = true
 
 [dev-dependencies]
-once_cell = "1.13.0"
+once_cell.workspace = true

libs/postgres_ffi/Cargo.toml

@@ -1,30 +1,31 @@
 [package]
 name = "postgres_ffi"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-rand = "0.8.3"
-regex = "1.4.5"
-bytes = "1.0.1"
-byteorder = "1.4.3"
-anyhow = "1.0"
-crc32c = "0.6.0"
-hex = "0.4.3"
-once_cell = "1.13.0"
-log = "0.4.14"
-memoffset = "0.7"
-thiserror = "1.0"
-serde = { version = "1.0", features = ["derive"] }
-utils = { path = "../utils" }
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+rand.workspace = true
+regex.workspace = true
+bytes.workspace = true
+byteorder.workspace = true
+anyhow.workspace = true
+crc32c.workspace = true
+hex.workspace = true
+once_cell.workspace = true
+log.workspace = true
+memoffset.workspace = true
+thiserror.workspace = true
+serde.workspace = true
+utils.workspace = true
+
+workspace_hack.workspace = true
 
 [dev-dependencies]
-env_logger = "0.9"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
+env_logger.workspace = true
+postgres.workspace = true
 wal_craft = { path = "wal_craft" }
 
 [build-dependencies]
-anyhow = "1.0"
-bindgen = "0.61"
+anyhow.workspace = true
+bindgen.workspace = true

libs/postgres_ffi/wal_craft/Cargo.toml

@@ -1,17 +1,17 @@
 [package]
 name = "wal_craft"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = "1.0"
-clap = "4.0"
-env_logger = "0.9"
-log = "0.4"
-once_cell = "1.13.0"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-postgres_ffi = { path = "../" }
-tempfile = "3.2"
-workspace_hack = { version = "0.1", path = "../../../workspace_hack" }
+anyhow.workspace = true
+clap.workspace = true
+env_logger.workspace = true
+log.workspace = true
+once_cell.workspace = true
+postgres.workspace = true
+postgres_ffi.workspace = true
+tempfile.workspace = true
+
+workspace_hack.workspace = true

libs/pq_proto/Cargo.toml

@@ -1,18 +1,18 @@
 [package]
 name = "pq_proto"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = "1.0"
-bytes = "1.0.1"
-pin-project-lite = "0.2.7"
-postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-rand = "0.8.3"
-serde = { version = "1.0", features = ["derive"] }
-tokio = { version = "1.17", features = ["macros"] }
-tracing = "0.1"
-thiserror = "1.0"
+anyhow.workspace = true
+bytes.workspace = true
+pin-project-lite.workspace = true
+postgres-protocol.workspace = true
+rand.workspace = true
+serde.workspace = true
+tokio.workspace = true
+tracing.workspace = true
+thiserror.workspace = true
 
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+workspace_hack.workspace = true

libs/remote_storage/Cargo.toml

@@ -1,28 +1,28 @@
 [package]
 name = "remote_storage"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-anyhow = { version = "1.0", features = ["backtrace"] }
-async-trait = "0.1"
-metrics = { version = "0.1", path = "../metrics" }
-utils = { version = "0.1", path = "../utils" }
-once_cell = "1.13.0"
-aws-smithy-http = "0.51.0"
-aws-types = "0.51.0"
-aws-config = { version = "0.51.0", default-features = false, features=["rustls"] }
-aws-sdk-s3 = "0.21.0"
-hyper = { version = "0.14", features = ["stream"] }
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1"
-tokio = { version = "1.17", features = ["sync", "macros", "fs", "io-util"] }
-tokio-util = { version = "0.7", features = ["io"] }
-toml_edit = { version = "0.14", features = ["easy"] }
-tracing = "0.1.27"
+anyhow.workspace = true
+async-trait.workspace = true
+once_cell.workspace = true
+aws-smithy-http.workspace = true
+aws-types.workspace = true
+aws-config.workspace = true
+aws-sdk-s3.workspace = true
+hyper = { workspace = true, features = ["stream"] }
+serde.workspace = true
+serde_json.workspace = true
+tokio = { workspace = true, features = ["sync", "fs", "io-util"] }
+tokio-util.workspace = true
+toml_edit.workspace = true
+tracing.workspace = true
+metrics.workspace = true
+utils.workspace = true
 
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+workspace_hack.workspace = true
 
 [dev-dependencies]
-tempfile = "3.2"
+tempfile.workspace = true

libs/safekeeper_api/Cargo.toml

@@ -1,13 +1,13 @@
 [package]
 name = "safekeeper_api"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-serde = { version = "1.0", features = ["derive"] }
-serde_with = "2.0"
-const_format = "0.2.21"
+serde.workspace = true
+serde_with.workspace = true
+const_format.workspace = true
+utils.workspace = true
 
-utils = { path = "../utils" }
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+workspace_hack.workspace = true

libs/tenant_size_model/Cargo.toml

@@ -1,9 +1,11 @@
 [package]
 name = "tenant_size_model"
 version = "0.1.0"
-edition = "2021"
+edition.workspace = true
 publish = false
-license = "Apache-2.0"
+license.workspace = true
 
 [dependencies]
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+anyhow.workspace = true
+
+workspace_hack.workspace = true

libs/tenant_size_model/src/lib.rs

@@ -1,6 +1,8 @@
 use std::borrow::Cow;
 use std::collections::HashMap;
 
+use anyhow::Context;
+
 /// Pricing model or history size builder.
 ///
 /// Maintains knowledge of the branches and their modifications. Generic over the branch name key
@@ -132,22 +134,25 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
         op: Cow<'static, str>,
         lsn: u64,
         size: Option<u64>,
-    ) where
+    ) -> anyhow::Result<()>
+    where
         K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
-        let lastseg_id = *self.branches.get(branch).unwrap();
+        let Some(lastseg_id) = self.branches.get(branch).copied() else { anyhow::bail!("branch not found: {branch:?}") };
         let newseg_id = self.segments.len();
         let lastseg = &mut self.segments[lastseg_id];
 
         assert!(lsn > lastseg.end_lsn);
 
+        let Some(start_size) = lastseg.end_size else { anyhow::bail!("no end_size on latest segment for {branch:?}") };
+
         let newseg = Segment {
             op,
             parent: Some(lastseg_id),
             start_lsn: lastseg.end_lsn,
             end_lsn: lsn,
-            start_size: lastseg.end_size.unwrap(),
+            start_size,
             end_size: size,
             children_after: Vec::new(),
             needed: false,
@@ -156,6 +161,8 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
 
         self.segments.push(newseg);
         *self.branches.get_mut(branch).expect("read already") = newseg_id;
+
+        Ok(())
     }
 
     /// Advances the branch with the named operation, by the relative LSN and logical size bytes.
@@ -165,21 +172,24 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
         op: Cow<'static, str>,
         lsn_bytes: u64,
         size_bytes: i64,
-    ) where
+    ) -> anyhow::Result<()>
+    where
         K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
-        let lastseg_id = *self.branches.get(branch).unwrap();
+        let Some(lastseg_id) = self.branches.get(branch).copied() else { anyhow::bail!("branch not found: {branch:?}") };
         let newseg_id = self.segments.len();
         let lastseg = &mut self.segments[lastseg_id];
 
+        let Some(last_end_size) = lastseg.end_size else { anyhow::bail!("no end_size on latest segment for {branch:?}") };
+
         let newseg = Segment {
             op,
             parent: Some(lastseg_id),
             start_lsn: lastseg.end_lsn,
             end_lsn: lastseg.end_lsn + lsn_bytes,
-            start_size: lastseg.end_size.unwrap(),
-            end_size: Some((lastseg.end_size.unwrap() as i64 + size_bytes) as u64),
+            start_size: last_end_size,
+            end_size: Some((last_end_size as i64 + size_bytes) as u64),
             children_after: Vec::new(),
             needed: false,
         };
@@ -187,50 +197,54 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
 
         self.segments.push(newseg);
         *self.branches.get_mut(branch).expect("read already") = newseg_id;
+        Ok(())
     }
 
-    pub fn insert<Q: ?Sized>(&mut self, branch: &Q, bytes: u64)
+    pub fn insert<Q: ?Sized>(&mut self, branch: &Q, bytes: u64) -> anyhow::Result<()>
     where
         K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
-        self.modify_branch(branch, "insert".into(), bytes, bytes as i64);
+        self.modify_branch(branch, "insert".into(), bytes, bytes as i64)
     }
 
-    pub fn update<Q: ?Sized>(&mut self, branch: &Q, bytes: u64)
+    pub fn update<Q: ?Sized>(&mut self, branch: &Q, bytes: u64) -> anyhow::Result<()>
     where
         K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
-        self.modify_branch(branch, "update".into(), bytes, 0i64);
+        self.modify_branch(branch, "update".into(), bytes, 0i64)
     }
 
-    pub fn delete<Q: ?Sized>(&mut self, branch: &Q, bytes: u64)
+    pub fn delete<Q: ?Sized>(&mut self, branch: &Q, bytes: u64) -> anyhow::Result<()>
     where
         K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
-        self.modify_branch(branch, "delete".into(), bytes, -(bytes as i64));
+        self.modify_branch(branch, "delete".into(), bytes, -(bytes as i64))
     }
 
-    /// Panics if the parent branch cannot be found.
-    pub fn branch<Q: ?Sized>(&mut self, parent: &Q, name: K)
+    pub fn branch<Q: ?Sized>(&mut self, parent: &Q, name: K) -> anyhow::Result<()>
     where
-        K: std::borrow::Borrow<Q>,
-        Q: std::hash::Hash + Eq,
+        K: std::borrow::Borrow<Q> + std::fmt::Debug,
+        Q: std::hash::Hash + Eq + std::fmt::Debug,
     {
         // Find the right segment
-        let branchseg_id = *self
-            .branches
-            .get(parent)
-            .expect("should had found the parent by key");
+        let branchseg_id = *self.branches.get(parent).with_context(|| {
+            format!(
+                "should had found the parent {:?} by key. in branches {:?}",
+                parent, self.branches
+            )
+        })?;
+
         let _branchseg = &mut self.segments[branchseg_id];
 
         // Create branch name for it
         self.branches.insert(name, branchseg_id);
+        Ok(())
     }
 
-    pub fn calculate(&mut self, retention_period: u64) -> SegmentSize {
+    pub fn calculate(&mut self, retention_period: u64) -> anyhow::Result<SegmentSize> {
         // Phase 1: Mark all the segments that need to be retained
         for (_branch, &last_seg_id) in self.branches.iter() {
             let last_seg = &self.segments[last_seg_id];
@@ -255,7 +269,7 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
         self.size_from_snapshot_later(0)
     }
 
-    fn size_from_wal(&self, seg_id: usize) -> SegmentSize {
+    fn size_from_wal(&self, seg_id: usize) -> anyhow::Result<SegmentSize> {
         let seg = &self.segments[seg_id];
 
         let this_size = seg.end_lsn - seg.start_lsn;
@@ -266,10 +280,10 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
         for &child_id in seg.children_after.iter() {
             // try each child both ways
             let child = &self.segments[child_id];
-            let p1 = self.size_from_wal(child_id);
+            let p1 = self.size_from_wal(child_id)?;
 
             let p = if !child.needed {
-                let p2 = self.size_from_snapshot_later(child_id);
+                let p2 = self.size_from_snapshot_later(child_id)?;
                 if p1.total() < p2.total() {
                     p1
                 } else {
@@ -280,15 +294,15 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
             };
             children.push(p);
         }
-        SegmentSize {
+        Ok(SegmentSize {
             seg_id,
             method: if seg.needed { WalNeeded } else { Wal },
             this_size,
             children,
-        }
+        })
     }
 
-    fn size_from_snapshot_later(&self, seg_id: usize) -> SegmentSize {
+    fn size_from_snapshot_later(&self, seg_id: usize) -> anyhow::Result<SegmentSize> {
         // If this is needed, then it's time to do the snapshot and continue
         // with wal method.
         let seg = &self.segments[seg_id];
@@ -299,10 +313,10 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
             for &child_id in seg.children_after.iter() {
                 // try each child both ways
                 let child = &self.segments[child_id];
-                let p1 = self.size_from_wal(child_id);
+                let p1 = self.size_from_wal(child_id)?;
 
                 let p = if !child.needed {
-                    let p2 = self.size_from_snapshot_later(child_id);
+                    let p2 = self.size_from_snapshot_later(child_id)?;
                     if p1.total() < p2.total() {
                         p1
                     } else {
@@ -313,12 +327,12 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
                 };
                 children.push(p);
             }
-            SegmentSize {
+            Ok(SegmentSize {
                 seg_id,
                 method: WalNeeded,
                 this_size: seg.start_size,
                 children,
-            }
+            })
         } else {
             // If any of the direct children are "needed", need to be able to reconstruct here
             let mut children_needed = false;
@@ -333,7 +347,7 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
             let method1 = if !children_needed {
                 let mut children = Vec::new();
                 for child in seg.children_after.iter() {
-                    children.push(self.size_from_snapshot_later(*child));
+                    children.push(self.size_from_snapshot_later(*child)?);
                 }
                 Some(SegmentSize {
                     seg_id,
@@ -349,20 +363,25 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
             let method2 = if children_needed || seg.children_after.len() >= 2 {
                 let mut children = Vec::new();
                 for child in seg.children_after.iter() {
-                    children.push(self.size_from_wal(*child));
+                    children.push(self.size_from_wal(*child)?);
                 }
+                let Some(this_size) = seg.end_size else { anyhow::bail!("no end_size at junction {seg_id}") };
                 Some(SegmentSize {
                     seg_id,
                     method: SnapshotAfter,
-                    this_size: seg.end_size.unwrap(),
+                    this_size,
                     children,
                 })
             } else {
                 None
             };
 
-            match (method1, method2) {
-                (None, None) => panic!(),
+            Ok(match (method1, method2) {
+                (None, None) => anyhow::bail!(
+                    "neither method was applicable: children_after={}, children_needed={}",
+                    seg.children_after.len(),
+                    children_needed
+                ),
                 (Some(method), None) => method,
                 (None, Some(method)) => method,
                 (Some(method1), Some(method2)) => {
@@ -372,7 +391,7 @@ impl<K: std::hash::Hash + Eq + 'static> Storage<K> {
                         method2
                     }
                 }
-            }
+            })
         }
     }
 

libs/tenant_size_model/src/main.rs

@@ -7,118 +7,118 @@
 use tenant_size_model::{Segment, SegmentSize, Storage};
 
 // Main branch only. Some updates on it.
-fn scenario_1() -> (Vec<Segment>, SegmentSize) {
+fn scenario_1() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     // Create main branch
     let mut storage = Storage::new("main");
 
     // Bulk load 5 GB of data to it
-    storage.insert("main", 5_000);
+    storage.insert("main", 5_000)?;
 
     // Stream of updates
     for _ in 0..5 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
-    let size = storage.calculate(1000);
+    let size = storage.calculate(1000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
 // Main branch only. Some updates on it.
-fn scenario_2() -> (Vec<Segment>, SegmentSize) {
+fn scenario_2() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     // Create main branch
     let mut storage = Storage::new("main");
 
     // Bulk load 5 GB of data to it
-    storage.insert("main", 5_000);
+    storage.insert("main", 5_000)?;
 
     // Stream of updates
     for _ in 0..5 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
     // Branch
-    storage.branch("main", "child");
-    storage.update("child", 1_000);
+    storage.branch("main", "child")?;
+    storage.update("child", 1_000)?;
 
     // More updates on parent
-    storage.update("main", 1_000);
+    storage.update("main", 1_000)?;
 
-    let size = storage.calculate(1000);
+    let size = storage.calculate(1000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
 // Like 2, but more updates on main
-fn scenario_3() -> (Vec<Segment>, SegmentSize) {
+fn scenario_3() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     // Create main branch
     let mut storage = Storage::new("main");
 
     // Bulk load 5 GB of data to it
-    storage.insert("main", 5_000);
+    storage.insert("main", 5_000)?;
 
     // Stream of updates
     for _ in 0..5 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
     // Branch
-    storage.branch("main", "child");
-    storage.update("child", 1_000);
+    storage.branch("main", "child")?;
+    storage.update("child", 1_000)?;
 
     // More updates on parent
     for _ in 0..5 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
-    let size = storage.calculate(1000);
+    let size = storage.calculate(1000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
 // Diverged branches
-fn scenario_4() -> (Vec<Segment>, SegmentSize) {
+fn scenario_4() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     // Create main branch
     let mut storage = Storage::new("main");
 
     // Bulk load 5 GB of data to it
-    storage.insert("main", 5_000);
+    storage.insert("main", 5_000)?;
 
     // Stream of updates
     for _ in 0..5 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
     // Branch
-    storage.branch("main", "child");
-    storage.update("child", 1_000);
+    storage.branch("main", "child")?;
+    storage.update("child", 1_000)?;
 
     // More updates on parent
     for _ in 0..8 {
-        storage.update("main", 1_000);
+        storage.update("main", 1_000)?;
     }
 
-    let size = storage.calculate(1000);
+    let size = storage.calculate(1000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
-fn scenario_5() -> (Vec<Segment>, SegmentSize) {
+fn scenario_5() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     let mut storage = Storage::new("a");
-    storage.insert("a", 5000);
-    storage.branch("a", "b");
-    storage.update("b", 4000);
-    storage.update("a", 2000);
-    storage.branch("a", "c");
-    storage.insert("c", 4000);
-    storage.insert("a", 2000);
+    storage.insert("a", 5000)?;
+    storage.branch("a", "b")?;
+    storage.update("b", 4000)?;
+    storage.update("a", 2000)?;
+    storage.branch("a", "c")?;
+    storage.insert("c", 4000)?;
+    storage.insert("a", 2000)?;
 
-    let size = storage.calculate(5000);
+    let size = storage.calculate(5000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
-fn scenario_6() -> (Vec<Segment>, SegmentSize) {
+fn scenario_6() -> anyhow::Result<(Vec<Segment>, SegmentSize)> {
     use std::borrow::Cow;
 
     const NO_OP: Cow<'static, str> = Cow::Borrowed("");
@@ -133,18 +133,18 @@ fn scenario_6() -> (Vec<Segment>, SegmentSize) {
 
     let mut storage = Storage::new(None);
 
-    storage.branch(&None, branches[0]); // at 0
-    storage.modify_branch(&branches[0], NO_OP, 108951064, 43696128); // at 108951064
-    storage.branch(&branches[0], branches[1]); // at 108951064
-    storage.modify_branch(&branches[1], NO_OP, 15560408, -1851392); // at 124511472
-    storage.modify_branch(&branches[0], NO_OP, 174464360, -1531904); // at 283415424
-    storage.branch(&branches[0], branches[2]); // at 283415424
-    storage.modify_branch(&branches[2], NO_OP, 15906192, 8192); // at 299321616
-    storage.modify_branch(&branches[0], NO_OP, 18909976, 32768); // at 302325400
+    storage.branch(&None, branches[0])?; // at 0
+    storage.modify_branch(&branches[0], NO_OP, 108951064, 43696128)?; // at 108951064
+    storage.branch(&branches[0], branches[1])?; // at 108951064
+    storage.modify_branch(&branches[1], NO_OP, 15560408, -1851392)?; // at 124511472
+    storage.modify_branch(&branches[0], NO_OP, 174464360, -1531904)?; // at 283415424
+    storage.branch(&branches[0], branches[2])?; // at 283415424
+    storage.modify_branch(&branches[2], NO_OP, 15906192, 8192)?; // at 299321616
+    storage.modify_branch(&branches[0], NO_OP, 18909976, 32768)?; // at 302325400
 
-    let size = storage.calculate(100_000);
+    let size = storage.calculate(100_000)?;
 
-    (storage.into_segments(), size)
+    Ok((storage.into_segments(), size))
 }
 
 fn main() {
@@ -163,7 +163,8 @@ fn main() {
             eprintln!("invalid scenario {}", other);
             std::process::exit(1);
         }
-    };
+    }
+    .unwrap();
 
     graphviz_tree(&segments, &size);
 }
@@ -251,7 +252,7 @@ fn graphviz_tree(segments: &[Segment], tree: &SegmentSize) {
 
 #[test]
 fn scenarios_return_same_size() {
-    type ScenarioFn = fn() -> (Vec<Segment>, SegmentSize);
+    type ScenarioFn = fn() -> anyhow::Result<(Vec<Segment>, SegmentSize)>;
     let truths: &[(u32, ScenarioFn, _)] = &[
         (line!(), scenario_1, 8000),
         (line!(), scenario_2, 9000),
@@ -262,7 +263,7 @@ fn scenarios_return_same_size() {
     ];
 
     for (line, scenario, expected) in truths {
-        let (_, size) = scenario();
+        let (_, size) = scenario().unwrap();
         assert_eq!(*expected, size.total_children(), "scenario on line {line}");
     }
 }

libs/tracing-utils/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "tracing-utils"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+
+[dependencies]
+hyper.workspace = true
+opentelemetry = { workspace = true, features=["rt-tokio"] }
+opentelemetry-otlp = { workspace = true, default_features=false, features = ["http-proto", "trace", "http", "reqwest-client"] }
+opentelemetry-semantic-conventions.workspace = true
+reqwest = { workspace = true, default-features = false, features = ["rustls-tls"] }
+tokio = { workspace = true, features = ["rt", "rt-multi-thread"] }
+tracing.workspace = true
+tracing-opentelemetry.workspace = true
+tracing-subscriber.workspace = true
+workspace_hack = { version = "0.1", path = "../../workspace_hack" }

libs/tracing-utils/src/http.rs

@@ -0,0 +1,96 @@
+//! Tracing wrapper for Hyper HTTP server
+
+use hyper::HeaderMap;
+use hyper::{Body, Request, Response};
+use std::future::Future;
+use tracing::Instrument;
+use tracing_opentelemetry::OpenTelemetrySpanExt;
+
+/// Configuration option for what to use as the "otel.name" field in the traces.
+pub enum OtelName<'a> {
+    /// Use a constant string
+    Constant(&'a str),
+
+    /// Use the path from the request.
+    ///
+    /// That's very useful information, but is not appropriate if the
+    /// path contains parameters that differ on ever request, or worse,
+    /// sensitive information like usernames or email addresses.
+    ///
+    /// See <https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/http.md#name>
+    UriPath,
+}
+
+/// Handle an incoming HTTP request using the given handler function,
+/// with OpenTelemetry tracing.
+///
+/// This runs 'handler' on the request in a new span, with fields filled in
+/// from the request. Notably, if the request contains tracing information,
+/// it is propagated to the span, so that this request is traced as part of
+/// the same trace.
+///
+/// XXX: Usually, this is handled by existing libraries, or built
+/// directly into HTTP servers. However, I couldn't find one for Hyper,
+/// so I had to write our own. OpenTelemetry website has a registry of
+/// instrumentation libraries at:
+/// https://opentelemetry.io/registry/?language=rust&component=instrumentation
+/// If a Hyper crate appears, consider switching to that.
+pub async fn tracing_handler<F, R>(
+    req: Request<Body>,
+    handler: F,
+    otel_name: OtelName<'_>,
+) -> Response<Body>
+where
+    F: Fn(Request<Body>) -> R,
+    R: Future<Output = Response<Body>>,
+{
+    // Create a tracing span, with context propagated from the incoming
+    // request if any.
+    //
+    // See list of standard fields defined for HTTP requests at
+    // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/http.md
+    // We only fill in a few of the most useful ones here.
+    let otel_name = match otel_name {
+        OtelName::Constant(s) => s,
+        OtelName::UriPath => req.uri().path(),
+    };
+
+    let span = tracing::info_span!(
+        "http request",
+        otel.name= %otel_name,
+        http.method = %req.method(),
+        http.status_code = tracing::field::Empty,
+    );
+    let parent_ctx = extract_remote_context(req.headers());
+    span.set_parent(parent_ctx);
+
+    // Handle the request within the span
+    let response = handler(req).instrument(span.clone()).await;
+
+    // Fill in the fields from the response code
+    let status = response.status();
+    span.record("http.status_code", status.as_str());
+    span.record(
+        "otel.status_code",
+        if status.is_success() { "OK" } else { "ERROR" },
+    );
+
+    response
+}
+
+// Extract remote tracing context from the HTTP headers
+fn extract_remote_context(headers: &HeaderMap) -> opentelemetry::Context {
+    struct HeaderExtractor<'a>(&'a HeaderMap);
+
+    impl<'a> opentelemetry::propagation::Extractor for HeaderExtractor<'a> {
+        fn get(&self, key: &str) -> Option<&str> {
+            self.0.get(key).and_then(|value| value.to_str().ok())
+        }
+
+        fn keys(&self) -> Vec<&str> {
+            self.0.keys().map(|value| value.as_str()).collect()
+        }
+    }
+    let extractor = HeaderExtractor(headers);
+    opentelemetry::global::get_text_map_propagator(|propagator| propagator.extract(&extractor))
+}

libs/tracing-utils/src/lib.rs

@@ -0,0 +1,168 @@
+//! Helper functions to set up OpenTelemetry tracing.
+//!
+//! This comes in two variants, depending on whether you have a Tokio runtime available.
+//! If you do, call `init_tracing()`. It sets up the trace processor and exporter to use
+//! the current tokio runtime. If you don't have a runtime available, or you don't want
+//! to share the runtime with the tracing tasks, call `init_tracing_without_runtime()`
+//! instead. It sets up a dedicated single-threaded Tokio runtime for the tracing tasks.
+//!
+//! Example:
+//!
+//! ```rust,no_run
+//! use tracing_subscriber::prelude::*;
+//! use tracing_opentelemetry::OpenTelemetryLayer;
+//!
+//! #[tokio::main]
+//! async fn main() {
+//!     // Set up logging to stderr
+//!     let env_filter = tracing_subscriber::EnvFilter::try_from_default_env()
+//!         .unwrap_or_else(|_| tracing_subscriber::EnvFilter::new("info"));
+//!     let fmt_layer = tracing_subscriber::fmt::layer()
+//!         .with_target(false)
+//!         .with_writer(std::io::stderr);
+//!
+//!     // Initialize OpenTelemetry. Exports tracing spans as OpenTelemetry traces
+//!     let otlp_layer = tracing_utils::init_tracing("my_application").await.map(OpenTelemetryLayer::new);
+//!
+//!     // Put it all together
+//!     tracing_subscriber::registry()
+//!         .with(env_filter)
+//!         .with(otlp_layer)
+//!         .with(fmt_layer)
+//!         .init();
+//! }
+//! ```
+
+use opentelemetry::sdk::Resource;
+use opentelemetry::KeyValue;
+use opentelemetry_otlp::WithExportConfig;
+use opentelemetry_otlp::{OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_TRACES_ENDPOINT};
+
+pub use tracing_opentelemetry::OpenTelemetryLayer;
+
+pub mod http;
+
+/// Set up OpenTelemetry exporter, using configuration from environment variables.
+///
+/// `service_name` is set as the OpenTelemetry 'service.name' resource (see
+/// <https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/resource/semantic_conventions/README.md#service>)
+///
+/// We try to follow the conventions for the environment variables specified in
+/// <https://opentelemetry.io/docs/reference/specification/sdk-environment-variables/>
+///
+/// However, we only support a subset of those options:
+///
+/// - OTEL_SDK_DISABLED is supported. The default is "false", meaning tracing
+///   is enabled by default. Set it to "true" to disable.
+///
+/// - We use the OTLP exporter, with HTTP protocol. Most of the OTEL_EXPORTER_OTLP_*
+///   settings specified in
+///   <https://opentelemetry.io/docs/reference/specification/protocol/exporter/>
+///   are supported, as they are handled by the `opentelemetry-otlp` crate.
+///   Settings related to other exporters have no effect.
+///
+/// - Some other settings are supported by the `opentelemetry` crate.
+///
+/// If you need some other setting, please test if it works first. And perhaps
+/// add a comment in the list above to save the effort of testing for the next
+/// person.
+///
+/// This doesn't block, but is marked as 'async' to hint that this must be called in
+/// asynchronous execution context.
+pub async fn init_tracing(service_name: &str) -> Option<opentelemetry::sdk::trace::Tracer> {
+    if std::env::var("OTEL_SDK_DISABLED") == Ok("true".to_string()) {
+        return None;
+    };
+    Some(init_tracing_internal(service_name.to_string()))
+}
+
+/// Like `init_tracing`, but creates a separate tokio Runtime for the tracing
+/// tasks.
+pub fn init_tracing_without_runtime(
+    service_name: &str,
+) -> Option<opentelemetry::sdk::trace::Tracer> {
+    if std::env::var("OTEL_SDK_DISABLED") == Ok("true".to_string()) {
+        return None;
+    };
+
+    // The opentelemetry batch processor and the OTLP exporter needs a Tokio
+    // runtime. Create a dedicated runtime for them. One thread should be
+    // enough.
+    //
+    // (Alternatively, instead of batching, we could use the "simple
+    // processor", which doesn't need Tokio, and use "reqwest-blocking"
+    // feature for the OTLP exporter, which also doesn't need Tokio.  However,
+    // batching is considered best practice, and also I have the feeling that
+    // the non-Tokio codepaths in the opentelemetry crate are less used and
+    // might be more buggy, so better to stay on the well-beaten path.)
+    //
+    // We leak the runtime so that it keeps running after we exit the
+    // function.
+    let runtime = Box::leak(Box::new(
+        tokio::runtime::Builder::new_multi_thread()
+            .enable_all()
+            .thread_name("otlp runtime thread")
+            .worker_threads(1)
+            .build()
+            .unwrap(),
+    ));
+    let _guard = runtime.enter();
+
+    Some(init_tracing_internal(service_name.to_string()))
+}
+
+fn init_tracing_internal(service_name: String) -> opentelemetry::sdk::trace::Tracer {
+    // Set up exporter from the OTEL_EXPORTER_* environment variables
+    let mut exporter = opentelemetry_otlp::new_exporter().http().with_env();
+
+    // XXX opentelemetry-otlp v0.18.0 has a bug in how it uses the
+    // OTEL_EXPORTER_OTLP_ENDPOINT env variable. According to the
+    // OpenTelemetry spec at
+    // <https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#endpoint-urls-for-otlphttp>,
+    // the full exporter URL is formed by appending "/v1/traces" to the value
+    // of OTEL_EXPORTER_OTLP_ENDPOINT. However, opentelemetry-otlp only does
+    // that with the grpc-tonic exporter. Other exporters, like the HTTP
+    // exporter, use the URL from OTEL_EXPORTER_OTLP_ENDPOINT as is, without
+    // appending "/v1/traces".
+    //
+    // See https://github.com/open-telemetry/opentelemetry-rust/pull/950
+    //
+    // Work around that by checking OTEL_EXPORTER_OTLP_ENDPOINT, and setting
+    // the endpoint url with the "/v1/traces" path ourselves. If the bug is
+    // fixed in a later version, we can remove this code. But if we don't
+    // remember to remove this, it won't do any harm either, as the crate will
+    // just ignore the OTEL_EXPORTER_OTLP_ENDPOINT setting when the endpoint
+    // is set directly with `with_endpoint`.
+    if std::env::var(OTEL_EXPORTER_OTLP_TRACES_ENDPOINT).is_err() {
+        if let Ok(mut endpoint) = std::env::var(OTEL_EXPORTER_OTLP_ENDPOINT) {
+            if !endpoint.ends_with('/') {
+                endpoint.push('/');
+            }
+            endpoint.push_str("v1/traces");
+            exporter = exporter.with_endpoint(endpoint);
+        }
+    }
+
+    // Propagate trace information in the standard W3C TraceContext format.
+    opentelemetry::global::set_text_map_propagator(
+        opentelemetry::sdk::propagation::TraceContextPropagator::new(),
+    );
+
+    opentelemetry_otlp::new_pipeline()
+        .tracing()
+        .with_exporter(exporter)
+        .with_trace_config(
+            opentelemetry::sdk::trace::config().with_resource(Resource::new(vec![KeyValue::new(
+                opentelemetry_semantic_conventions::resource::SERVICE_NAME,
+                service_name,
+            )])),
+        )
+        .install_batch(opentelemetry::runtime::Tokio)
+        .expect("could not initialize opentelemetry exporter")
+}
+
+// Shutdown trace pipeline gracefully, so that it has a chance to send any
+// pending traces before we exit.
+pub fn shutdown_tracing() {
+    opentelemetry::global::shutdown_tracer_provider();
+}

libs/utils/Cargo.toml

@@ -1,48 +1,50 @@
 [package]
 name = "utils"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [dependencies]
-sentry = { version = "0.29.0", default-features = false, features = ["backtrace", "contexts", "panic", "rustls", "reqwest" ] }
-async-trait = "0.1"
-anyhow = "1.0"
-bincode = "1.3"
-bytes = "1.0.1"
-hyper = { version = "0.14.7", features = ["full"] }
-routerify = "3"
-serde = { version = "1.0", features = ["derive"] }
-serde_json = "1"
-thiserror = "1.0"
-tokio = { version = "1.17", features = ["macros"]}
-tokio-rustls = "0.23"
-tracing = "0.1"
-tracing-subscriber = { version = "0.3", features = ["env-filter", "json"] }
-nix = "0.25"
-signal-hook = "0.3.10"
-rand = "0.8.3"
-jsonwebtoken = "8"
-hex = { version = "0.4.3", features = ["serde"] }
-rustls = "0.20.2"
-rustls-split = "0.3.0"
-git-version = "0.3.5"
-serde_with = "2.0"
-once_cell = "1.13.0"
-strum = "0.24"
-strum_macros = "0.24"
+atty.workspace = true
+sentry.workspace = true
+async-trait.workspace = true
+anyhow.workspace = true
+bincode.workspace = true
+bytes.workspace = true
+hyper = { workspace = true, features = ["full"] }
+routerify.workspace = true
+serde.workspace = true
+serde_json.workspace = true
+thiserror.workspace = true
+tokio.workspace = true
+tokio-rustls.workspace = true
+tracing.workspace = true
+tracing-subscriber = { workspace = true, features = ["json"] }
+nix.workspace = true
+signal-hook.workspace = true
+rand.workspace = true
+jsonwebtoken.workspace = true
+hex = { workspace = true, features = ["serde"] }
+rustls.workspace = true
+rustls-split.workspace = true
+git-version.workspace = true
+serde_with.workspace = true
+once_cell.workspace = true
+strum.workspace = true
+strum_macros.workspace = true
 
-metrics = { path = "../metrics" }
-pq_proto = { path = "../pq_proto" }
-workspace_hack = { version = "0.1", path = "../../workspace_hack" }
+metrics.workspace = true
+pq_proto.workspace = true
+
+workspace_hack.workspace = true
 
 [dev-dependencies]
-byteorder = "1.4.3"
-bytes = "1.0.1"
-hex-literal = "0.3"
-tempfile = "3.2"
-criterion = "0.4"
-rustls-pemfile = "1"
+byteorder.workspace = true
+bytes.workspace = true
+hex-literal.workspace = true
+tempfile.workspace = true
+criterion.workspace = true
+rustls-pemfile.workspace = true
 
 [[bench]]
 name = "benchmarks"

libs/utils/src/http/error.rs

@@ -1,6 +1,7 @@
 use hyper::{header, Body, Response, StatusCode};
 use serde::{Deserialize, Serialize};
 use thiserror::Error;
+use tracing::error;
 
 #[derive(Debug, Error)]
 pub enum ApiError {
@@ -76,8 +77,16 @@ impl HttpErrorBody {
 }
 
 pub async fn handler(err: routerify::RouteError) -> Response<Body> {
-    tracing::error!("Error processing HTTP request: {:?}", err);
-    err.downcast::<ApiError>()
-        .expect("handler should always return api error")
-        .into_response()
+    let api_error = err
+        .downcast::<ApiError>()
+        .expect("handler should always return api error");
+
+    // Print a stack trace for Internal Server errors
+    if let ApiError::InternalServerError(_) = api_error.as_ref() {
+        error!("Error processing HTTP request: {api_error:?}");
+    } else {
+        error!("Error processing HTTP request: {api_error:#}");
+    }
+
+    api_error.into_response()
 }

libs/utils/src/logging.rs

@@ -8,6 +8,7 @@ use strum_macros::{EnumString, EnumVariantNames};
 pub enum LogFormat {
     Plain,
     Json,
+    Test,
 }
 
 impl LogFormat {
@@ -33,12 +34,13 @@ pub fn init(log_format: LogFormat) -> anyhow::Result<()> {
     let base_logger = tracing_subscriber::fmt()
         .with_env_filter(env_filter)
         .with_target(false)
-        .with_ansi(false)
+        .with_ansi(atty::is(atty::Stream::Stdout))
         .with_writer(std::io::stdout);
 
     match log_format {
         LogFormat::Json => base_logger.json().init(),
         LogFormat::Plain => base_logger.init(),
+        LogFormat::Test => base_logger.with_test_writer().init(),
     }
 
     Ok(())

libs/utils/src/postgres_backend_async.rs

@@ -7,12 +7,12 @@ use crate::postgres_backend::AuthType;
 use anyhow::Context;
 use bytes::{Buf, Bytes, BytesMut};
 use pq_proto::{BeMessage, ConnectionError, FeMessage, FeStartupPacket, SQLSTATE_INTERNAL_ERROR};
-use std::future::Future;
 use std::io;
 use std::net::SocketAddr;
 use std::pin::Pin;
 use std::sync::Arc;
 use std::task::Poll;
+use std::{future::Future, task::ready};
 use tracing::{debug, error, info, trace};
 
 use tokio::io::{AsyncRead, AsyncWrite, AsyncWriteExt, BufReader};
@@ -253,12 +253,9 @@ impl PostgresBackend {
         cx: &mut std::task::Context<'_>,
     ) -> Poll<Result<(), std::io::Error>> {
         while self.buf_out.has_remaining() {
-            match Pin::new(&mut self.stream).poll_write(cx, self.buf_out.chunk()) {
-                Poll::Ready(Ok(bytes_written)) => {
-                    self.buf_out.advance(bytes_written);
-                }
-                Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
-                Poll::Pending => return Poll::Pending,
+            match ready!(Pin::new(&mut self.stream).poll_write(cx, self.buf_out.chunk())) {
+                Ok(bytes_written) => self.buf_out.advance(bytes_written),
+                Err(err) => return Poll::Ready(Err(err)),
             }
         }
         Poll::Ready(Ok(()))
@@ -573,10 +570,9 @@ impl<'a> AsyncWrite for CopyDataWriter<'a> {
         // It's not strictly required to flush between each message, but makes it easier
         // to view in wireshark, and usually the messages that the callers write are
         // decently-sized anyway.
-        match this.pgb.poll_write_buf(cx) {
-            Poll::Ready(Ok(())) => {}
-            Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
-            Poll::Pending => return Poll::Pending,
+        match ready!(this.pgb.poll_write_buf(cx)) {
+            Ok(()) => {}
+            Err(err) => return Poll::Ready(Err(err)),
         }
 
         // CopyData
@@ -593,10 +589,9 @@ impl<'a> AsyncWrite for CopyDataWriter<'a> {
         cx: &mut std::task::Context<'_>,
     ) -> Poll<Result<(), std::io::Error>> {
         let this = self.get_mut();
-        match this.pgb.poll_write_buf(cx) {
-            Poll::Ready(Ok(())) => {}
-            Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
-            Poll::Pending => return Poll::Pending,
+        match ready!(this.pgb.poll_write_buf(cx)) {
+            Ok(()) => {}
+            Err(err) => return Poll::Ready(Err(err)),
         }
         this.pgb.poll_flush(cx)
     }
@@ -605,10 +600,9 @@ impl<'a> AsyncWrite for CopyDataWriter<'a> {
         cx: &mut std::task::Context<'_>,
     ) -> Poll<Result<(), std::io::Error>> {
         let this = self.get_mut();
-        match this.pgb.poll_write_buf(cx) {
-            Poll::Ready(Ok(())) => {}
-            Poll::Ready(Err(err)) => return Poll::Ready(Err(err)),
-            Poll::Pending => return Poll::Pending,
+        match ready!(this.pgb.poll_write_buf(cx)) {
+            Ok(()) => {}
+            Err(err) => return Poll::Ready(Err(err)),
         }
         this.pgb.poll_flush(cx)
     }

pageserver/Cargo.toml

@@ -1,8 +1,8 @@
 [package]
 name = "pageserver"
 version = "0.1.0"
-edition = "2021"
-license = "Apache-2.0"
+edition.workspace = true
+license.workspace = true
 
 [features]
 default = []
@@ -11,68 +11,67 @@ default = []
 testing = ["fail/failpoints"]
 
 [dependencies]
-amplify_num = { git = "https://github.com/hlinnaka/rust-amplify.git", branch = "unsigned-int-perf" }
-anyhow = { version = "1.0", features = ["backtrace"] }
-async-stream = "0.3"
-async-trait = "0.1"
-byteorder = "1.4.3"
-bytes = "1.0.1"
-chrono = { version = "0.4.23", default-features = false, features = ["clock", "serde"] }
-clap = { version = "4.0", features = ["string"] }
-close_fds = "0.3.2"
-const_format = "0.2.21"
-crc32c = "0.6.0"
-crossbeam-utils = "0.8.5"
-fail = "0.5.0"
-futures = "0.3.13"
-git-version = "0.3.5"
-hex = "0.4.3"
-humantime = "2.1.0"
-humantime-serde = "1.1.1"
-hyper = "0.14"
-itertools = "0.10.3"
-nix = "0.25"
-num-traits = "0.2.15"
-once_cell = "1.13.0"
-pin-project-lite = "0.2.7"
-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-postgres-protocol = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-postgres-types = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-rand = "0.8.3"
-regex = "1.4.5"
-rstar = "0.9.3"
-scopeguard = "1.1.0"
-serde = { version = "1.0", features = ["derive"] }
-serde_json = { version = "1.0", features = ["raw_value"] }
-serde_with = "2.0"
-signal-hook = "0.3.10"
-svg_fmt = "0.4.1"
-tokio-tar = { git = "https://github.com/neondatabase/tokio-tar.git", rev="404df61437de0feef49ba2ccdbdd94eb8ad6e142" }
-thiserror = "1.0"
-tokio = { version = "1.17", features = ["process", "sync", "macros", "fs", "rt", "io-util", "time"] }
-tokio-postgres = { git = "https://github.com/neondatabase/rust-postgres.git", rev="43e6db254a97fdecbce33d8bc0890accfd74495e" }
-tokio-util = { version = "0.7.3", features = ["io", "io-util"] }
-toml_edit = { version = "0.14", features = ["easy"] }
-tracing = "0.1.36"
-url = "2"
-walkdir = "2.3.2"
-
-metrics = { path = "../libs/metrics" }
-pageserver_api = { path = "../libs/pageserver_api" }
-postgres_connection = { path = "../libs/postgres_connection" }
-postgres_ffi = { path = "../libs/postgres_ffi" }
-pq_proto = { path = "../libs/pq_proto" }
-remote_storage = { path = "../libs/remote_storage" }
-storage_broker = { version = "0.1", path = "../storage_broker" }
-tenant_size_model = { path = "../libs/tenant_size_model" }
-utils = { path = "../libs/utils" }
-workspace_hack = { version = "0.1", path = "../workspace_hack" }
-reqwest = { version = "0.11", default-features = false, features = ["rustls-tls"] }
+anyhow.workspace = true
+async-stream.workspace = true
+async-trait.workspace = true
+byteorder.workspace = true
+bytes.workspace = true
+chrono = { workspace = true, features = ["serde"] }
+clap = { workspace = true, features = ["string"] }
+close_fds.workspace = true
+const_format.workspace = true
+consumption_metrics.workspace = true
+crc32c.workspace = true
+crossbeam-utils.workspace = true
+fail.workspace = true
+futures.workspace = true
+git-version.workspace = true
+hex.workspace = true
+humantime.workspace = true
+humantime-serde.workspace = true
+hyper.workspace = true
+itertools.workspace = true
+nix.workspace = true
+num-traits.workspace = true
+once_cell.workspace = true
+pin-project-lite.workspace = true
+postgres.workspace = true
+postgres-protocol.workspace = true
+postgres-types.workspace = true
+rand.workspace = true
+regex.workspace = true
+scopeguard.workspace = true
+serde.workspace = true
+serde_json = { workspace = true, features = ["raw_value"] }
+serde_with.workspace = true
+signal-hook.workspace = true
+svg_fmt.workspace = true
+tokio-tar.workspace = true
+thiserror.workspace = true
+tokio = { workspace = true, features = ["process", "sync", "fs", "rt", "io-util", "time"] }
+tokio-postgres.workspace = true
+tokio-util.workspace = true
+toml_edit.workspace = true
+tracing.workspace = true
+url.workspace = true
+walkdir.workspace = true
+metrics.workspace = true
+pageserver_api.workspace = true
+postgres_connection.workspace = true
+postgres_ffi.workspace = true
+pq_proto.workspace = true
+remote_storage.workspace = true
+storage_broker.workspace = true
+tenant_size_model.workspace = true
+utils.workspace = true
+workspace_hack.workspace = true
+reqwest.workspace = true
+rpds.workspace = true
 
 [dev-dependencies]
-criterion = "0.4"
-hex-literal = "0.3"
-tempfile = "3.2"
+criterion.workspace = true
+hex-literal.workspace = true
+tempfile.workspace = true
 
 [[bench]]
 name = "bench_layer_map"

pageserver/benches/bench_layer_map.rs

@@ -1,13 +1,12 @@
-use anyhow::Result;
+use pageserver::keyspace::{KeyPartitioning, KeySpace};
 use pageserver::repository::Key;
 use pageserver::tenant::layer_map::LayerMap;
-use pageserver::tenant::storage_layer::{DeltaFileName, ImageFileName, ValueReconstructState};
-use pageserver::tenant::storage_layer::{Layer, ValueReconstructResult};
+use pageserver::tenant::storage_layer::Layer;
+use pageserver::tenant::storage_layer::{DeltaFileName, ImageFileName, LayerDescriptor};
 use rand::prelude::{SeedableRng, SliceRandom, StdRng};
 use std::cmp::{max, min};
 use std::fs::File;
 use std::io::{BufRead, BufReader};
-use std::ops::Range;
 use std::path::PathBuf;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -17,102 +16,35 @@ use utils::lsn::Lsn;
 
 use criterion::{criterion_group, criterion_main, Criterion};
 
-struct DummyDelta {
-    key_range: Range<Key>,
-    lsn_range: Range<Lsn>,
-}
-
-impl Layer for DummyDelta {
-    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,
-        _lsn_range: Range<Lsn>,
-        _reconstruct_data: &mut ValueReconstructState,
-    ) -> Result<ValueReconstructResult> {
-        panic!()
-    }
-
-    fn is_incremental(&self) -> bool {
-        true
-    }
-
-    fn dump(&self, _verbose: bool) -> Result<()> {
-        unimplemented!()
-    }
-
-    fn short_id(&self) -> String {
-        unimplemented!()
-    }
-}
-
-struct DummyImage {
-    key_range: Range<Key>,
-    lsn: Lsn,
-}
-
-impl Layer for DummyImage {
-    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 get_value_reconstruct_data(
-        &self,
-        _key: Key,
-        _lsn_range: Range<Lsn>,
-        _reconstruct_data: &mut ValueReconstructState,
-    ) -> Result<ValueReconstructResult> {
-        panic!()
-    }
-
-    fn is_incremental(&self) -> bool {
-        false
-    }
-
-    fn dump(&self, _verbose: bool) -> Result<()> {
-        unimplemented!()
-    }
-
-    fn short_id(&self) -> String {
-        unimplemented!()
-    }
-}
-
-fn build_layer_map(filename_dump: PathBuf) -> LayerMap<dyn Layer> {
-    let mut layer_map = LayerMap::<dyn Layer>::default();
+fn build_layer_map(filename_dump: PathBuf) -> LayerMap<LayerDescriptor> {
+    let mut layer_map = LayerMap::<LayerDescriptor>::default();
 
     let mut min_lsn = Lsn(u64::MAX);
     let mut max_lsn = Lsn(0);
 
     let filenames = BufReader::new(File::open(filename_dump).unwrap()).lines();
 
+    let mut updates = layer_map.batch_update();
     for fname in filenames {
         let fname = &fname.unwrap();
         if let Some(imgfilename) = ImageFileName::parse_str(fname) {
-            let layer = DummyImage {
-                key_range: imgfilename.key_range,
-                lsn: imgfilename.lsn,
+            let layer = LayerDescriptor {
+                key: imgfilename.key_range,
+                lsn: imgfilename.lsn..(imgfilename.lsn + 1),
+                is_incremental: false,
+                short_id: fname.to_string(),
             };
-            layer_map.insert_historic(Arc::new(layer));
+            updates.insert_historic(Arc::new(layer));
             min_lsn = min(min_lsn, imgfilename.lsn);
             max_lsn = max(max_lsn, imgfilename.lsn);
         } else if let Some(deltafilename) = DeltaFileName::parse_str(fname) {
-            let layer = DummyDelta {
-                key_range: deltafilename.key_range,
-                lsn_range: deltafilename.lsn_range.clone(),
+            let layer = LayerDescriptor {
+                key: deltafilename.key_range.clone(),
+                lsn: deltafilename.lsn_range.clone(),
+                is_incremental: true,
+                short_id: fname.to_string(),
             };
-            layer_map.insert_historic(Arc::new(layer));
+            updates.insert_historic(Arc::new(layer));
             min_lsn = min(min_lsn, deltafilename.lsn_range.start);
             max_lsn = max(max_lsn, deltafilename.lsn_range.end);
         } else {
@@ -122,11 +54,12 @@ fn build_layer_map(filename_dump: PathBuf) -> LayerMap<dyn Layer> {
 
     println!("min: {min_lsn}, max: {max_lsn}");
 
+    updates.flush();
     layer_map
 }
 
 /// Construct a layer map query pattern for benchmarks
-fn uniform_query_pattern(layer_map: &LayerMap<dyn Layer>) -> Vec<(Key, Lsn)> {
+fn uniform_query_pattern(layer_map: &LayerMap<LayerDescriptor>) -> Vec<(Key, Lsn)> {
     // For each image layer we query one of the pages contained, at LSN right
     // before the image layer was created. This gives us a somewhat uniform
     // coverage of both the lsn and key space because image layers have
@@ -150,6 +83,41 @@ fn uniform_query_pattern(layer_map: &LayerMap<dyn Layer>) -> Vec<(Key, Lsn)> {
         .collect()
 }
 
+// Construct a partitioning for testing get_difficulty map when we
+// don't have an exact result of `collect_keyspace` to work with.
+fn uniform_key_partitioning(layer_map: &LayerMap<LayerDescriptor>, _lsn: Lsn) -> KeyPartitioning {
+    let mut parts = Vec::new();
+
+    // We add a partition boundary at the start of each image layer,
+    // no matter what lsn range it covers. This is just the easiest
+    // thing to do. A better thing to do would be to get a real
+    // partitioning from some database. Even better, remove the need
+    // for key partitions by deciding where to create image layers
+    // directly based on a coverage-based difficulty map.
+    let mut keys: Vec<_> = layer_map
+        .iter_historic_layers()
+        .filter_map(|l| {
+            if l.is_incremental() {
+                None
+            } else {
+                let kr = l.get_key_range();
+                Some(kr.start.next())
+            }
+        })
+        .collect();
+    keys.sort();
+
+    let mut current_key = Key::from_hex("000000000000000000000000000000000000").unwrap();
+    for key in keys {
+        parts.push(KeySpace {
+            ranges: vec![current_key..key],
+        });
+        current_key = key;
+    }
+
+    KeyPartitioning { parts }
+}
+
 // Benchmark using metadata extracted from our performance test environment, from
 // a project where we have run pgbench many timmes. The pgbench database was initialized
 // between each test run.
@@ -183,24 +151,68 @@ fn bench_from_captest_env(c: &mut Criterion) {
 // Benchmark using metadata extracted from a real project that was taknig
 // too long processing layer map queries.
 fn bench_from_real_project(c: &mut Criterion) {
-    // TODO consider compressing this file
+    // Init layer map
+    let now = Instant::now();
     let layer_map = build_layer_map(PathBuf::from("benches/odd-brook-layernames.txt"));
+    println!("Finished layer map init in {:?}", now.elapsed());
+
+    // Choose uniformly distributed queries
     let queries: Vec<(Key, Lsn)> = uniform_query_pattern(&layer_map);
 
-    // Test with uniform query pattern
-    c.bench_function("real_map_uniform_queries", |b| {
+    // Choose inputs for get_difficulty_map
+    let latest_lsn = layer_map
+        .iter_historic_layers()
+        .map(|l| l.get_lsn_range().end)
+        .max()
+        .unwrap();
+    let partitioning = uniform_key_partitioning(&layer_map, latest_lsn);
+
+    // Check correctness of get_difficulty_map
+    // TODO put this in a dedicated test outside of this mod
+    {
+        println!("running correctness check");
+
+        let now = Instant::now();
+        let result_bruteforce = layer_map.get_difficulty_map_bruteforce(latest_lsn, &partitioning);
+        assert!(result_bruteforce.len() == partitioning.parts.len());
+        println!("Finished bruteforce in {:?}", now.elapsed());
+
+        let now = Instant::now();
+        let result_fast = layer_map.get_difficulty_map(latest_lsn, &partitioning, None);
+        assert!(result_fast.len() == partitioning.parts.len());
+        println!("Finished fast in {:?}", now.elapsed());
+
+        // Assert results are equal. Manually iterate for easier debugging.
+        let zip = std::iter::zip(
+            &partitioning.parts,
+            std::iter::zip(result_bruteforce, result_fast),
+        );
+        for (_part, (bruteforce, fast)) in zip {
+            assert_eq!(bruteforce, fast);
+        }
+
+        println!("No issues found");
+    }
+
+    // Define and name the benchmark function
+    let mut group = c.benchmark_group("real_map");
+    group.bench_function("uniform_queries", |b| {
         b.iter(|| {
             for q in queries.clone().into_iter() {
                 layer_map.search(q.0, q.1);
             }
         });
     });
+    group.bench_function("get_difficulty_map", |b| {
+        b.iter(|| {
+            layer_map.get_difficulty_map(latest_lsn, &partitioning, Some(3));
+        });
+    });
+    group.finish();
 }
 
 // Benchmark using synthetic data. Arrange image layers on stacked diagonal lines.
 fn bench_sequential(c: &mut Criterion) {
-    let mut layer_map: LayerMap<dyn Layer> = LayerMap::default();
-
     // Init layer map. Create 100_000 layers arranged in 1000 diagonal lines.
     //
     // TODO This code is pretty slow and runs even if we're only running other
@@ -208,39 +220,39 @@ fn bench_sequential(c: &mut Criterion) {
     //      Putting it inside the `bench_function` closure is not a solution
     //      because then it runs multiple times during warmup.
     let now = Instant::now();
+    let mut layer_map = LayerMap::default();
+    let mut updates = layer_map.batch_update();
     for i in 0..100_000 {
-        // TODO try inserting a super-wide layer in between every 10 to reflect
-        //      what often happens with L1 layers that include non-rel changes.
-        //      Maybe do that as a separate test.
         let i32 = (i as u32) % 100;
         let zero = Key::from_hex("000000000000000000000000000000000000").unwrap();
-        let layer = DummyImage {
-            key_range: zero.add(10 * i32)..zero.add(10 * i32 + 1),
-            lsn: Lsn(10 * i),
+        let layer = LayerDescriptor {
+            key: zero.add(10 * i32)..zero.add(10 * i32 + 1),
+            lsn: Lsn(i)..Lsn(i + 1),
+            is_incremental: false,
+            short_id: format!("Layer {}", i),
         };
-        layer_map.insert_historic(Arc::new(layer));
+        updates.insert_historic(Arc::new(layer));
     }
-
-    // Manually measure runtime without criterion because criterion
-    // has a minimum sample size of 10 and I don't want to run it 10 times.
-    println!("Finished init in {:?}", now.elapsed());
+    updates.flush();
+    println!("Finished layer map init in {:?}", now.elapsed());
 
     // Choose 100 uniformly random queries
     let rng = &mut StdRng::seed_from_u64(1);
     let queries: Vec<(Key, Lsn)> = uniform_query_pattern(&layer_map)
-        .choose_multiple(rng, 1)
+        .choose_multiple(rng, 100)
         .copied()
         .collect();
 
     // Define and name the benchmark function
-    c.bench_function("sequential_uniform_queries", |b| {
-        // Run the search queries
+    let mut group = c.benchmark_group("sequential");
+    group.bench_function("uniform_queries", |b| {
         b.iter(|| {
             for q in queries.clone().into_iter() {
                 layer_map.search(q.0, q.1);
             }
         });
     });
+    group.finish();
 }
 
 criterion_group!(group_1, bench_from_captest_env);

pageserver/benches/bench_walredo.rs

@@ -30,33 +30,44 @@ fn redo_scenarios(c: &mut Criterion) {
     let conf = PageServerConf::dummy_conf(repo_dir.path().to_path_buf());
     let conf = Box::leak(Box::new(conf));
     let tenant_id = TenantId::generate();
-    // std::fs::create_dir_all(conf.tenant_path(&tenant_id)).unwrap();
-    let mut manager = PostgresRedoManager::new(conf, tenant_id);
-    manager.launch_process(14).unwrap();
+
+    let manager = PostgresRedoManager::new(conf, tenant_id);
 
     let manager = Arc::new(manager);
 
+    tracing::info!("executing first");
+    short().execute(&manager).unwrap();
+    tracing::info!("first executed");
+
     let thread_counts = [1, 2, 4, 8, 16];
 
-    for thread_count in thread_counts {
-        c.bench_with_input(
-            BenchmarkId::new("short-50record", thread_count),
-            &thread_count,
-            |b, thread_count| {
-                add_multithreaded_walredo_requesters(b, *thread_count, &manager, short, 50);
-            },
-        );
-    }
+    let mut group = c.benchmark_group("short");
+    group.sampling_mode(criterion::SamplingMode::Flat);
 
     for thread_count in thread_counts {
-        c.bench_with_input(
-            BenchmarkId::new("medium-10record", thread_count),
+        group.bench_with_input(
+            BenchmarkId::new("short", thread_count),
             &thread_count,
             |b, thread_count| {
-                add_multithreaded_walredo_requesters(b, *thread_count, &manager, medium, 10);
+                add_multithreaded_walredo_requesters(b, *thread_count, &manager, short);
             },
         );
     }
+    drop(group);
+
+    let mut group = c.benchmark_group("medium");
+    group.sampling_mode(criterion::SamplingMode::Flat);
+
+    for thread_count in thread_counts {
+        group.bench_with_input(
+            BenchmarkId::new("medium", thread_count),
+            &thread_count,
+            |b, thread_count| {
+                add_multithreaded_walredo_requesters(b, *thread_count, &manager, medium);
+            },
+        );
+    }
+    drop(group);
 }
 
 /// Sets up `threads` number of requesters to `request_redo`, with the given input.
@@ -65,46 +76,66 @@ fn add_multithreaded_walredo_requesters(
     threads: u32,
     manager: &Arc<PostgresRedoManager>,
     input_factory: fn() -> Request,
-    request_repeats: usize,
 ) {
-    b.iter_batched_ref(
-        || {
-            // barrier for all of the threads, and the benchmarked thread
-            let barrier = Arc::new(Barrier::new(threads as usize + 1));
+    assert_ne!(threads, 0);
 
-            let jhs = (0..threads)
-                .map(|_| {
-                    std::thread::spawn({
-                        let manager = manager.clone();
-                        let barrier = barrier.clone();
-                        move || {
-                            let input = std::iter::repeat(input_factory())
-                                .take(request_repeats)
-                                .collect::<Vec<_>>();
+    if threads == 1 {
+        b.iter_batched_ref(
+            || Some(input_factory()),
+            |input| execute_all(input.take(), manager),
+            criterion::BatchSize::PerIteration,
+        );
+    } else {
+        let (work_tx, work_rx) = std::sync::mpsc::sync_channel(threads as usize);
 
-                            barrier.wait();
+        let work_rx = std::sync::Arc::new(std::sync::Mutex::new(work_rx));
 
-                            execute_all(input, &manager).unwrap();
+        let barrier = Arc::new(Barrier::new(threads as usize + 1));
 
-                            barrier.wait();
+        let jhs = (0..threads)
+            .map(|_| {
+                std::thread::spawn({
+                    let manager = manager.clone();
+                    let barrier = barrier.clone();
+                    let work_rx = work_rx.clone();
+                    move || loop {
+                        // queue up and wait if we want to go another round
+                        if work_rx.lock().unwrap().recv().is_err() {
+                            break;
                         }
-                    })
+
+                        let input = Some(input_factory());
+
+                        barrier.wait();
+
+                        execute_all(input, &manager).unwrap();
+
+                        barrier.wait();
+                    }
                 })
-                .collect::<Vec<_>>();
+            })
+            .collect::<Vec<_>>();
 
-            (barrier, JoinOnDrop(jhs))
-        },
-        |input| {
-            let barrier = &input.0;
+        let _jhs = JoinOnDrop(jhs);
 
-            // start the work
-            barrier.wait();
+        b.iter_batched(
+            || {
+                for _ in 0..threads {
+                    work_tx.send(()).unwrap()
+                }
+            },
+            |()| {
+                // start the work
+                barrier.wait();
 
-            // wait for work to complete
-            barrier.wait();
-        },
-        criterion::BatchSize::PerIteration,
-    );
+                // wait for work to complete
+                barrier.wait();
+            },
+            criterion::BatchSize::PerIteration,
+        );
+
+        drop(work_tx);
+    }
 }
 
 struct JoinOnDrop(Vec<std::thread::JoinHandle<()>>);
@@ -121,7 +152,10 @@ impl Drop for JoinOnDrop {
     }
 }
 
-fn execute_all(input: Vec<Request>, manager: &PostgresRedoManager) -> Result<(), WalRedoError> {
+fn execute_all<I>(input: I, manager: &PostgresRedoManager) -> Result<(), WalRedoError>
+where
+    I: IntoIterator<Item = Request>,
+{
     // just fire all requests as fast as possible
     input.into_iter().try_for_each(|req| {
         let page = req.execute(manager)?;
@@ -143,6 +177,7 @@ macro_rules! lsn {
     }};
 }
 
+/// Short payload, 1132 bytes.
 // pg_records are copypasted from log, where they are put with Debug impl of Bytes, which uses \0
 // for null bytes.
 #[allow(clippy::octal_escapes)]
@@ -172,6 +207,7 @@ fn short() -> Request {
     }
 }
 
+/// Medium sized payload, serializes as 26393 bytes.
 // see [`short`]
 #[allow(clippy::octal_escapes)]
 fn medium() -> Request {

pageserver/src/basebackup.rs

@@ -27,6 +27,7 @@ use tracing::*;
 ///
 use tokio_tar::{Builder, EntryType, Header};
 
+use crate::context::RequestContext;
 use crate::tenant::Timeline;
 use pageserver_api::reltag::{RelTag, SlruKind};
 
@@ -52,6 +53,7 @@ pub async fn send_basebackup_tarball<'a, W>(
     req_lsn: Option<Lsn>,
     prev_lsn: Option<Lsn>,
     full_backup: bool,
+    ctx: &'a RequestContext,
 ) -> anyhow::Result<()>
 where
     W: AsyncWrite + Send + Sync + Unpin,
@@ -110,6 +112,7 @@ where
         lsn: backup_lsn,
         prev_record_lsn: prev_lsn,
         full_backup,
+        ctx,
     };
     basebackup
         .send_tarball()
@@ -129,6 +132,7 @@ where
     lsn: Lsn,
     prev_record_lsn: Lsn,
     full_backup: bool,
+    ctx: &'a RequestContext,
 }
 
 impl<'a, W> Basebackup<'a, W>
@@ -171,23 +175,37 @@ where
             SlruKind::MultiXactOffsets,
             SlruKind::MultiXactMembers,
         ] {
-            for segno in self.timeline.list_slru_segments(kind, self.lsn).await? {
+            for segno in self
+                .timeline
+                .list_slru_segments(kind, self.lsn, self.ctx)
+                .await?
+            {
                 self.add_slru_segment(kind, segno).await?;
             }
         }
 
         // Create tablespace directories
-        for ((spcnode, dbnode), has_relmap_file) in self.timeline.list_dbdirs(self.lsn).await? {
+        for ((spcnode, dbnode), has_relmap_file) in
+            self.timeline.list_dbdirs(self.lsn, self.ctx).await?
+        {
             self.add_dbdir(spcnode, dbnode, has_relmap_file).await?;
 
             // Gather and send relational files in each database if full backup is requested.
             if self.full_backup {
-                for rel in self.timeline.list_rels(spcnode, dbnode, self.lsn).await? {
+                for rel in self
+                    .timeline
+                    .list_rels(spcnode, dbnode, self.lsn, self.ctx)
+                    .await?
+                {
                     self.add_rel(rel).await?;
                 }
             }
         }
-        for xid in self.timeline.list_twophase_files(self.lsn).await? {
+        for xid in self
+            .timeline
+            .list_twophase_files(self.lsn, self.ctx)
+            .await?
+        {
             self.add_twophase_file(xid).await?;
         }
 
@@ -203,7 +221,10 @@ where
     }
 
     async fn add_rel(&mut self, tag: RelTag) -> anyhow::Result<()> {
-        let nblocks = self.timeline.get_rel_size(tag, self.lsn, false).await?;
+        let nblocks = self
+            .timeline
+            .get_rel_size(tag, self.lsn, false, self.ctx)
+            .await?;
 
         // If the relation is empty, create an empty file
         if nblocks == 0 {
@@ -223,7 +244,7 @@ where
             for blknum in startblk..endblk {
                 let img = self
                     .timeline
-                    .get_rel_page_at_lsn(tag, blknum, self.lsn, false)
+                    .get_rel_page_at_lsn(tag, blknum, self.lsn, false, self.ctx)
                     .await?;
                 segment_data.extend_from_slice(&img[..]);
             }
@@ -245,14 +266,14 @@ where
     async fn add_slru_segment(&mut self, slru: SlruKind, segno: u32) -> anyhow::Result<()> {
         let nblocks = self
             .timeline
-            .get_slru_segment_size(slru, segno, self.lsn)
+            .get_slru_segment_size(slru, segno, self.lsn, self.ctx)
             .await?;
 
         let mut slru_buf: Vec<u8> = Vec::with_capacity(nblocks as usize * BLCKSZ as usize);
         for blknum in 0..nblocks {
             let img = self
                 .timeline
-                .get_slru_page_at_lsn(slru, segno, blknum, self.lsn)
+                .get_slru_page_at_lsn(slru, segno, blknum, self.lsn, self.ctx)
                 .await?;
 
             if slru == SlruKind::Clog {
@@ -287,7 +308,7 @@ where
         let relmap_img = if has_relmap_file {
             let img = self
                 .timeline
-                .get_relmap_file(spcnode, dbnode, self.lsn)
+                .get_relmap_file(spcnode, dbnode, self.lsn, self.ctx)
                 .await?;
             ensure!(img.len() == 512);
             Some(img)
@@ -323,7 +344,7 @@ where
             if !has_relmap_file
                 && self
                     .timeline
-                    .list_rels(spcnode, dbnode, self.lsn)
+                    .list_rels(spcnode, dbnode, self.lsn, self.ctx)
                     .await?
                     .is_empty()
             {
@@ -356,7 +377,10 @@ where
     // Extract twophase state files
     //
     async fn add_twophase_file(&mut self, xid: TransactionId) -> anyhow::Result<()> {
-        let img = self.timeline.get_twophase_file(xid, self.lsn).await?;
+        let img = self
+            .timeline
+            .get_twophase_file(xid, self.lsn, self.ctx)
+            .await?;
 
         let mut buf = BytesMut::new();
         buf.extend_from_slice(&img[..]);
@@ -394,12 +418,12 @@ where
 
         let checkpoint_bytes = self
             .timeline
-            .get_checkpoint(self.lsn)
+            .get_checkpoint(self.lsn, self.ctx)
             .await
             .context("failed to get checkpoint bytes")?;
         let pg_control_bytes = self
             .timeline
-            .get_control_file(self.lsn)
+            .get_control_file(self.lsn, self.ctx)
             .await
             .context("failed get control bytes")?;
 

pageserver/src/bin/pageserver.rs

@@ -13,6 +13,7 @@ use tracing::*;
 use metrics::set_build_info_metric;
 use pageserver::{
     config::{defaults::*, PageServerConf},
+    context::{DownloadBehavior, RequestContext},
     http, page_cache, page_service, task_mgr,
     task_mgr::TaskKind,
     task_mgr::{
@@ -26,7 +27,7 @@ use utils::{
     logging,
     postgres_backend::AuthType,
     project_git_version,
-    sentry_init::{init_sentry, release_name},
+    sentry_init::init_sentry,
     signals::{self, Signal},
     tcp_listener,
 };
@@ -85,7 +86,10 @@ fn main() -> anyhow::Result<()> {
     };
 
     // initialize sentry if SENTRY_DSN is provided
-    let _sentry_guard = init_sentry(release_name!(), &[("node_id", &conf.id.to_string())]);
+    let _sentry_guard = init_sentry(
+        Some(GIT_VERSION.into()),
+        &[("node_id", &conf.id.to_string())],
+    );
 
     let tenants_path = conf.tenants_path();
     if !tenants_path.exists() {
@@ -325,6 +329,13 @@ fn start_pageserver(conf: &'static PageServerConf) -> anyhow::Result<()> {
         );
 
         if let Some(metric_collection_endpoint) = &conf.metric_collection_endpoint {
+            let metrics_ctx = RequestContext::todo_child(
+                TaskKind::MetricsCollection,
+                // This task itself shouldn't download anything.
+                // The actual size calculation does need downloads, and
+                // creates a child context with the right DownloadBehavior.
+                DownloadBehavior::Error,
+            );
             task_mgr::spawn(
                 MGMT_REQUEST_RUNTIME.handle(),
                 TaskKind::MetricsCollection,
@@ -336,7 +347,9 @@ fn start_pageserver(conf: &'static PageServerConf) -> anyhow::Result<()> {
                     pageserver::consumption_metrics::collect_metrics(
                         metric_collection_endpoint,
                         conf.metric_collection_interval,
+                        conf.synthetic_size_calculation_interval,
                         conf.id,
+                        metrics_ctx,
                     )
                     .instrument(info_span!("metrics_collection"))
                     .await?;
@@ -348,17 +361,34 @@ fn start_pageserver(conf: &'static PageServerConf) -> anyhow::Result<()> {
 
     // Spawn a task to listen for libpq connections. It will spawn further tasks
     // for each connection. We created the listener earlier already.
-    task_mgr::spawn(
-        COMPUTE_REQUEST_RUNTIME.handle(),
-        TaskKind::LibpqEndpointListener,
-        None,
-        None,
-        "libpq endpoint listener",
-        true,
-        async move {
-            page_service::libpq_listener_main(conf, auth, pageserver_listener, conf.auth_type).await
-        },
-    );
+    {
+        let libpq_ctx = RequestContext::todo_child(
+            TaskKind::LibpqEndpointListener,
+            // listener task shouldn't need to download anything. (We will
+            // create a separate sub-contexts for each connection, with their
+            // own download behavior. This context is used only to listen and
+            // accept connections.)
+            DownloadBehavior::Error,
+        );
+        task_mgr::spawn(
+            COMPUTE_REQUEST_RUNTIME.handle(),
+            TaskKind::LibpqEndpointListener,
+            None,
+            None,
+            "libpq endpoint listener",
+            true,
+            async move {
+                page_service::libpq_listener_main(
+                    conf,
+                    auth,
+                    pageserver_listener,
+                    conf.auth_type,
+                    libpq_ctx,
+                )
+                .await
+            },
+        );
+    }
 
     // All started up! Now just sit and wait for shutdown signal.
     signals.handle(|signal| match signal {

pageserver/src/config.rs

@@ -59,6 +59,8 @@ pub mod defaults {
 
     pub const DEFAULT_METRIC_COLLECTION_INTERVAL: &str = "10 min";
     pub const DEFAULT_METRIC_COLLECTION_ENDPOINT: Option<reqwest::Url> = None;
+    pub const DEFAULT_SYNTHETIC_SIZE_CALCULATION_INTERVAL: &str = "10 min";
+
     ///
     /// Default built-in configuration file.
     ///
@@ -83,6 +85,7 @@ pub mod defaults {
 #concurrent_tenant_size_logical_size_queries = '{DEFAULT_CONCURRENT_TENANT_SIZE_LOGICAL_SIZE_QUERIES}'
 
 #metric_collection_interval = '{DEFAULT_METRIC_COLLECTION_INTERVAL}'
+#synthetic_size_calculation_interval = '{DEFAULT_SYNTHETIC_SIZE_CALCULATION_INTERVAL}'
 
 # [tenant_config]
 #checkpoint_distance = {DEFAULT_CHECKPOINT_DISTANCE} # in bytes
@@ -152,8 +155,11 @@ pub struct PageServerConf {
     // How often to collect metrics and send them to the metrics endpoint.
     pub metric_collection_interval: Duration,
     pub metric_collection_endpoint: Option<Url>,
+    pub synthetic_size_calculation_interval: Duration,
 
     pub test_remote_failures: u64,
+
+    pub ondemand_download_behavior_treat_error_as_warn: bool,
 }
 
 /// We do not want to store this in a PageServerConf because the latter may be logged
@@ -215,8 +221,11 @@ struct PageServerConfigBuilder {
 
     metric_collection_interval: BuilderValue<Duration>,
     metric_collection_endpoint: BuilderValue<Option<Url>>,
+    synthetic_size_calculation_interval: BuilderValue<Duration>,
 
     test_remote_failures: BuilderValue<u64>,
+
+    ondemand_download_behavior_treat_error_as_warn: BuilderValue<bool>,
 }
 
 impl Default for PageServerConfigBuilder {
@@ -255,9 +264,15 @@ impl Default for PageServerConfigBuilder {
                 DEFAULT_METRIC_COLLECTION_INTERVAL,
             )
             .expect("cannot parse default metric collection interval")),
+            synthetic_size_calculation_interval: Set(humantime::parse_duration(
+                DEFAULT_SYNTHETIC_SIZE_CALCULATION_INTERVAL,
+            )
+            .expect("cannot parse default synthetic size calculation interval")),
             metric_collection_endpoint: Set(DEFAULT_METRIC_COLLECTION_ENDPOINT),
 
             test_remote_failures: Set(0),
+
+            ondemand_download_behavior_treat_error_as_warn: Set(false),
         }
     }
 }
@@ -342,10 +357,26 @@ impl PageServerConfigBuilder {
         self.metric_collection_endpoint = BuilderValue::Set(metric_collection_endpoint)
     }
 
+    pub fn synthetic_size_calculation_interval(
+        &mut self,
+        synthetic_size_calculation_interval: Duration,
+    ) {
+        self.synthetic_size_calculation_interval =
+            BuilderValue::Set(synthetic_size_calculation_interval)
+    }
+
     pub fn test_remote_failures(&mut self, fail_first: u64) {
         self.test_remote_failures = BuilderValue::Set(fail_first);
     }
 
+    pub fn ondemand_download_behavior_treat_error_as_warn(
+        &mut self,
+        ondemand_download_behavior_treat_error_as_warn: bool,
+    ) {
+        self.ondemand_download_behavior_treat_error_as_warn =
+            BuilderValue::Set(ondemand_download_behavior_treat_error_as_warn);
+    }
+
     pub fn build(self) -> anyhow::Result<PageServerConf> {
         Ok(PageServerConf {
             listen_pg_addr: self
@@ -399,9 +430,17 @@ impl PageServerConfigBuilder {
             metric_collection_endpoint: self
                 .metric_collection_endpoint
                 .ok_or(anyhow!("missing metric_collection_endpoint"))?,
+            synthetic_size_calculation_interval: self
+                .synthetic_size_calculation_interval
+                .ok_or(anyhow!("missing synthetic_size_calculation_interval"))?,
             test_remote_failures: self
                 .test_remote_failures
                 .ok_or(anyhow!("missing test_remote_failuers"))?,
+            ondemand_download_behavior_treat_error_as_warn: self
+                .ondemand_download_behavior_treat_error_as_warn
+                .ok_or(anyhow!(
+                    "missing ondemand_download_behavior_treat_error_as_warn"
+                ))?,
         })
     }
 }
@@ -577,8 +616,10 @@ impl PageServerConf {
                     let endpoint = parse_toml_string(key, item)?.parse().context("failed to parse metric_collection_endpoint")?;
                     builder.metric_collection_endpoint(Some(endpoint));
                 },
-
+                "synthetic_size_calculation_interval" =>
+                    builder.synthetic_size_calculation_interval(parse_toml_duration(key, item)?),
                 "test_remote_failures" => builder.test_remote_failures(parse_toml_u64(key, item)?),
+                "ondemand_download_behavior_treat_error_as_warn" => builder.ondemand_download_behavior_treat_error_as_warn(parse_toml_bool(key, item)?),
                 _ => bail!("unrecognized pageserver option '{key}'"),
             }
         }
@@ -701,7 +742,9 @@ impl PageServerConf {
             concurrent_tenant_size_logical_size_queries: ConfigurableSemaphore::default(),
             metric_collection_interval: Duration::from_secs(60),
             metric_collection_endpoint: defaults::DEFAULT_METRIC_COLLECTION_ENDPOINT,
+            synthetic_size_calculation_interval: Duration::from_secs(60),
             test_remote_failures: 0,
+            ondemand_download_behavior_treat_error_as_warn: false,
         }
     }
 }
@@ -727,6 +770,11 @@ fn parse_toml_u64(name: &str, item: &Item) -> Result<u64> {
     Ok(i as u64)
 }
 
+fn parse_toml_bool(name: &str, item: &Item) -> Result<bool> {
+    item.as_bool()
+        .with_context(|| format!("configure option {name} is not a bool"))
+}
+
 fn parse_toml_duration(name: &str, item: &Item) -> Result<Duration> {
     let s = item
         .as_str()
@@ -834,6 +882,7 @@ id = 10
 
 metric_collection_interval = '222 s'
 metric_collection_endpoint = 'http://localhost:80/metrics'
+synthetic_size_calculation_interval = '333 s'
 log_format = 'json'
 
 "#;
@@ -880,7 +929,11 @@ log_format = 'json'
                     defaults::DEFAULT_METRIC_COLLECTION_INTERVAL
                 )?,
                 metric_collection_endpoint: defaults::DEFAULT_METRIC_COLLECTION_ENDPOINT,
+                synthetic_size_calculation_interval: humantime::parse_duration(
+                    defaults::DEFAULT_SYNTHETIC_SIZE_CALCULATION_INTERVAL
+                )?,
                 test_remote_failures: 0,
+                ondemand_download_behavior_treat_error_as_warn: false,
             },
             "Correct defaults should be used when no config values are provided"
         );
@@ -926,7 +979,9 @@ log_format = 'json'
                 concurrent_tenant_size_logical_size_queries: ConfigurableSemaphore::default(),
                 metric_collection_interval: Duration::from_secs(222),
                 metric_collection_endpoint: Some(Url::parse("http://localhost:80/metrics")?),
+                synthetic_size_calculation_interval: Duration::from_secs(333),
                 test_remote_failures: 0,
+                ondemand_download_behavior_treat_error_as_warn: false,
             },
             "Should be able to parse all basic config values correctly"
         );

pageserver/src/consumption_metrics.rs

@@ -3,154 +3,78 @@
 //! and push them to a HTTP endpoint.
 //! Cache metrics to send only the updated ones.
 //!
-
-use anyhow;
-use tracing::*;
-use utils::id::NodeId;
-use utils::id::TimelineId;
-
-use crate::task_mgr;
+use crate::context::{DownloadBehavior, RequestContext};
+use crate::task_mgr::{self, TaskKind, BACKGROUND_RUNTIME};
 use crate::tenant::mgr;
+use anyhow;
+use chrono::Utc;
+use consumption_metrics::{idempotency_key, Event, EventChunk, EventType, CHUNK_SIZE};
 use pageserver_api::models::TenantState;
-use utils::id::TenantId;
-
-use serde::{Deserialize, Serialize};
+use reqwest::Url;
+use serde::Serialize;
 use serde_with::{serde_as, DisplayFromStr};
 use std::collections::HashMap;
-use std::fmt;
-use std::str::FromStr;
 use std::time::Duration;
+use tracing::*;
+use utils::id::{NodeId, TenantId, TimelineId};
 
-use chrono::{DateTime, Utc};
-use rand::Rng;
-use reqwest::Url;
+const WRITTEN_SIZE: &str = "written_size";
+const SYNTHETIC_STORAGE_SIZE: &str = "synthetic_storage_size";
+const RESIDENT_SIZE: &str = "resident_size";
+const REMOTE_STORAGE_SIZE: &str = "remote_storage_size";
+const TIMELINE_LOGICAL_SIZE: &str = "timeline_logical_size";
 
-/// ConsumptionMetric struct that defines the format for one metric entry
-/// i.e.
-///
-/// ```json
-/// {
-/// "metric": "remote_storage_size",
-/// "type": "absolute",
-/// "tenant_id": "5d07d9ce9237c4cd845ea7918c0afa7d",
-/// "timeline_id": "a03ebb4f5922a1c56ff7485cc8854143",
-/// "time": "2022-12-28T11:07:19.317310284Z",
-/// "idempotency_key": "2022-12-28 11:07:19.317310324 UTC-1-4019",
-/// "value": 12345454,
-/// }
-/// ```
 #[serde_as]
-#[derive(Serialize, Deserialize, Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
-pub struct ConsumptionMetric {
-    pub metric: ConsumptionMetricKind,
-    #[serde(rename = "type")]
-    pub metric_type: &'static str,
+#[derive(Serialize)]
+struct Ids {
     #[serde_as(as = "DisplayFromStr")]
-    pub tenant_id: TenantId,
+    tenant_id: TenantId,
     #[serde_as(as = "Option<DisplayFromStr>")]
     #[serde(skip_serializing_if = "Option::is_none")]
-    pub timeline_id: Option<TimelineId>,
-    pub time: DateTime<Utc>,
-    pub idempotency_key: String,
-    pub value: u64,
-}
-
-impl ConsumptionMetric {
-    pub fn new_absolute<R: Rng + ?Sized>(
-        metric: ConsumptionMetricKind,
-        tenant_id: TenantId,
-        timeline_id: Option<TimelineId>,
-        value: u64,
-        node_id: NodeId,
-        rng: &mut R,
-    ) -> Self {
-        Self {
-            metric,
-            metric_type: "absolute",
-            tenant_id,
-            timeline_id,
-            time: Utc::now(),
-            // key that allows metric collector to distinguish unique events
-            idempotency_key: format!("{}-{}-{:04}", Utc::now(), node_id, rng.gen_range(0..=9999)),
-            value,
-        }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Ord, PartialOrd, Serialize, Deserialize)]
-#[serde(rename_all = "snake_case")]
-pub enum ConsumptionMetricKind {
-    /// Amount of WAL produced , by a timeline, i.e. last_record_lsn
-    /// This is an absolute, per-timeline metric.
-    WrittenSize,
-    /// Size of all tenant branches including WAL
-    /// This is an absolute, per-tenant metric.
-    /// This is the same metric that tenant/tenant_id/size endpoint returns.
-    SyntheticStorageSize,
-    /// Size of all the layer files in the tenant's directory on disk on the pageserver.
-    /// This is an absolute, per-tenant metric.
-    /// See also prometheus metric RESIDENT_PHYSICAL_SIZE.
-    ResidentSize,
-    /// Size of the remote storage (S3) directory.
-    /// This is an absolute, per-tenant metric.
-    RemoteStorageSize,
-    /// Logical size of the data in the timeline
-    /// This is an absolute, per-timeline metric
-    TimelineLogicalSize,
-}
-
-impl FromStr for ConsumptionMetricKind {
-    type Err = anyhow::Error;
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        match s {
-            "written_size" => Ok(Self::WrittenSize),
-            "synthetic_storage_size" => Ok(Self::SyntheticStorageSize),
-            "resident_size" => Ok(Self::ResidentSize),
-            "remote_storage_size" => Ok(Self::RemoteStorageSize),
-            "timeline_logical_size" => Ok(Self::TimelineLogicalSize),
-            _ => anyhow::bail!("invalid value \"{s}\" for metric type"),
-        }
-    }
-}
-
-impl fmt::Display for ConsumptionMetricKind {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.write_str(match self {
-            ConsumptionMetricKind::WrittenSize => "written_size",
-            ConsumptionMetricKind::SyntheticStorageSize => "synthetic_storage_size",
-            ConsumptionMetricKind::ResidentSize => "resident_size",
-            ConsumptionMetricKind::RemoteStorageSize => "remote_storage_size",
-            ConsumptionMetricKind::TimelineLogicalSize => "timeline_logical_size",
-        })
-    }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct ConsumptionMetricsKey {
-    tenant_id: TenantId,
     timeline_id: Option<TimelineId>,
-    metric: ConsumptionMetricKind,
 }
 
-#[derive(serde::Serialize)]
-struct EventChunk<'a> {
-    events: &'a [ConsumptionMetric],
+/// Key that uniquely identifies the object, this metric describes.
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct PageserverConsumptionMetricsKey {
+    pub tenant_id: TenantId,
+    pub timeline_id: Option<TimelineId>,
+    pub metric: &'static str,
 }
 
 /// Main thread that serves metrics collection
 pub async fn collect_metrics(
     metric_collection_endpoint: &Url,
     metric_collection_interval: Duration,
+    synthetic_size_calculation_interval: Duration,
     node_id: NodeId,
+    ctx: RequestContext,
 ) -> anyhow::Result<()> {
     let mut ticker = tokio::time::interval(metric_collection_interval);
 
     info!("starting collect_metrics");
 
+    // spin up background worker that caclulates tenant sizes
+    let worker_ctx =
+        ctx.detached_child(TaskKind::CalculateSyntheticSize, DownloadBehavior::Download);
+    task_mgr::spawn(
+        BACKGROUND_RUNTIME.handle(),
+        TaskKind::CalculateSyntheticSize,
+        None,
+        None,
+        "synthetic size calculation",
+        false,
+        async move {
+            calculate_synthetic_size_worker(synthetic_size_calculation_interval, &worker_ctx)
+                .instrument(info_span!("synthetic_size_worker"))
+                .await?;
+            Ok(())
+        },
+    );
+
     // define client here to reuse it for all requests
     let client = reqwest::Client::new();
-    let mut cached_metrics: HashMap<ConsumptionMetricsKey, u64> = HashMap::new();
+    let mut cached_metrics: HashMap<PageserverConsumptionMetricsKey, u64> = HashMap::new();
 
     loop {
         tokio::select! {
@@ -159,7 +83,10 @@ pub async fn collect_metrics(
                 return Ok(());
             },
             _ = ticker.tick() => {
-                collect_metrics_task(&client, &mut cached_metrics, metric_collection_endpoint, node_id).await?;
+                if let Err(err) = collect_metrics_iteration(&client, &mut cached_metrics, metric_collection_endpoint, node_id, &ctx).await
+                {
+                    error!("metrics collection failed: {err:?}");
+                }
             }
         }
     }
@@ -169,20 +96,26 @@ pub async fn collect_metrics(
 ///
 /// Gather per-tenant and per-timeline metrics and send them to the `metric_collection_endpoint`.
 /// Cache metrics to avoid sending the same metrics multiple times.
-pub async fn collect_metrics_task(
+///
+/// TODO
+/// - refactor this function (chunking+sending part) to reuse it in proxy module;
+/// - improve error handling. Now if one tenant fails to collect metrics,
+/// the whole iteration fails and metrics for other tenants are not collected.
+pub async fn collect_metrics_iteration(
     client: &reqwest::Client,
-    cached_metrics: &mut HashMap<ConsumptionMetricsKey, u64>,
+    cached_metrics: &mut HashMap<PageserverConsumptionMetricsKey, u64>,
     metric_collection_endpoint: &reqwest::Url,
     node_id: NodeId,
+    ctx: &RequestContext,
 ) -> anyhow::Result<()> {
-    let mut current_metrics: Vec<(ConsumptionMetricsKey, u64)> = Vec::new();
+    let mut current_metrics: Vec<(PageserverConsumptionMetricsKey, u64)> = Vec::new();
     trace!(
-        "starting collect_metrics_task. metric_collection_endpoint: {}",
+        "starting collect_metrics_iteration. metric_collection_endpoint: {}",
         metric_collection_endpoint
     );
 
     // get list of tenants
-    let tenants = mgr::list_tenants().await;
+    let tenants = mgr::list_tenants().await?;
 
     // iterate through list of Active tenants and collect metrics
     for (tenant_id, tenant_state) in tenants {
@@ -201,22 +134,22 @@ pub async fn collect_metrics_task(
                 let timeline_written_size = u64::from(timeline.get_last_record_lsn());
 
                 current_metrics.push((
-                    ConsumptionMetricsKey {
+                    PageserverConsumptionMetricsKey {
                         tenant_id,
                         timeline_id: Some(timeline.timeline_id),
-                        metric: ConsumptionMetricKind::WrittenSize,
+                        metric: WRITTEN_SIZE,
                     },
                     timeline_written_size,
                 ));
 
-                let (timeline_logical_size, is_exact) = timeline.get_current_logical_size()?;
+                let (timeline_logical_size, is_exact) = timeline.get_current_logical_size(ctx)?;
                 // Only send timeline logical size when it is fully calculated.
                 if is_exact {
                     current_metrics.push((
-                        ConsumptionMetricsKey {
+                        PageserverConsumptionMetricsKey {
                             tenant_id,
                             timeline_id: Some(timeline.timeline_id),
-                            metric: ConsumptionMetricKind::TimelineLogicalSize,
+                            metric: TIMELINE_LOGICAL_SIZE,
                         },
                         timeline_logical_size,
                     ));
@@ -234,24 +167,34 @@ pub async fn collect_metrics_task(
         );
 
         current_metrics.push((
-            ConsumptionMetricsKey {
+            PageserverConsumptionMetricsKey {
                 tenant_id,
                 timeline_id: None,
-                metric: ConsumptionMetricKind::ResidentSize,
+                metric: RESIDENT_SIZE,
             },
             tenant_resident_size,
         ));
 
         current_metrics.push((
-            ConsumptionMetricsKey {
+            PageserverConsumptionMetricsKey {
                 tenant_id,
                 timeline_id: None,
-                metric: ConsumptionMetricKind::RemoteStorageSize,
+                metric: REMOTE_STORAGE_SIZE,
             },
             tenant_remote_size,
         ));
 
-        // TODO add SyntheticStorageSize metric
+        // Note that this metric is calculated in a separate bgworker
+        // Here we only use cached value, which may lag behind the real latest one
+        let tenant_synthetic_size = tenant.get_cached_synthetic_size();
+        current_metrics.push((
+            PageserverConsumptionMetricsKey {
+                tenant_id,
+                timeline_id: None,
+                metric: SYNTHETIC_STORAGE_SIZE,
+            },
+            tenant_synthetic_size,
+        ));
     }
 
     // Filter metrics
@@ -267,35 +210,29 @@ pub async fn collect_metrics_task(
 
     // Send metrics.
     // Split into chunks of 1000 metrics to avoid exceeding the max request size
-    const CHUNK_SIZE: usize = 1000;
     let chunks = current_metrics.chunks(CHUNK_SIZE);
 
-    let mut chunk_to_send: Vec<ConsumptionMetric> = Vec::with_capacity(1000);
+    let mut chunk_to_send: Vec<Event<Ids>> = Vec::with_capacity(CHUNK_SIZE);
 
     for chunk in chunks {
         chunk_to_send.clear();
 
-        // this code block is needed to convince compiler
-        // that rng is not reused aroung await point
-        {
-            // enrich metrics with timestamp and metric_kind before sending
-            let mut rng = rand::thread_rng();
-            chunk_to_send.extend(chunk.iter().map(|(curr_key, curr_val)| {
-                ConsumptionMetric::new_absolute(
-                    curr_key.metric,
-                    curr_key.tenant_id,
-                    curr_key.timeline_id,
-                    *curr_val,
-                    node_id,
-                    &mut rng,
-                )
-            }));
-        }
+        // enrich metrics with type,timestamp and idempotency key before sending
+        chunk_to_send.extend(chunk.iter().map(|(curr_key, curr_val)| Event {
+            kind: EventType::Absolute { time: Utc::now() },
+            metric: curr_key.metric,
+            idempotency_key: idempotency_key(node_id.to_string()),
+            value: *curr_val,
+            extra: Ids {
+                tenant_id: curr_key.tenant_id,
+                timeline_id: curr_key.timeline_id,
+            },
+        }));
 
         let chunk_json = serde_json::value::to_raw_value(&EventChunk {
             events: &chunk_to_send,
         })
-        .expect("ConsumptionMetric should not fail serialization");
+        .expect("PageserverConsumptionMetric should not fail serialization");
 
         let res = client
             .post(metric_collection_endpoint.clone())
@@ -322,3 +259,46 @@ pub async fn collect_metrics_task(
 
     Ok(())
 }
+
+/// Caclculate synthetic size for each active tenant
+pub async fn calculate_synthetic_size_worker(
+    synthetic_size_calculation_interval: Duration,
+    ctx: &RequestContext,
+) -> anyhow::Result<()> {
+    info!("starting calculate_synthetic_size_worker");
+
+    let mut ticker = tokio::time::interval(synthetic_size_calculation_interval);
+
+    loop {
+        tokio::select! {
+            _ = task_mgr::shutdown_watcher() => {
+                return Ok(());
+            },
+        _ = ticker.tick() => {
+
+                let tenants = match mgr::list_tenants().await {
+                    Ok(tenants) => tenants,
+                    Err(e) => {
+                        warn!("cannot get tenant list: {e:#}");
+                        continue;
+                    }
+                };
+                // iterate through list of Active tenants and collect metrics
+                for (tenant_id, tenant_state) in tenants {
+
+                    if tenant_state != TenantState::Active {
+                        continue;
+                    }
+
+                    if let Ok(tenant) = mgr::get_tenant(tenant_id, true).await
+                    {
+                        if let Err(e) = tenant.calculate_synthetic_size(ctx).await {
+                            error!("failed to calculate synthetic size for tenant {}: {}", tenant_id, e);
+                        }
+                    }
+
+                }
+            }
+        }
+    }
+}

pageserver/src/context.rs

@@ -0,0 +1,199 @@
+//! This module defines `RequestContext`, a structure that we use throughout
+//! the pageserver to propagate high-level context from places
+//! that _originate_ activity down to the shared code paths at the
+//! heart of the pageserver. It's inspired by Golang's `context.Context`.
+//!
+//! For example, in `Timeline::get(page_nr, lsn)` we need to answer the following questions:
+//! 1. What high-level activity ([`TaskKind`]) needs this page?
+//!    We need that information as a categorical dimension for page access
+//!    statistics, which we, in turn, need to guide layer eviction policy design.
+//! 2. How should we behave if, to produce the page image, we need to
+//!    on-demand download a layer file ([`DownloadBehavior`]).
+//!
+//! [`RequestContext`] satisfies those needs.
+//! The current implementation is a small `struct` that is passed through
+//! the call chain by reference.
+//!
+//! ### Future Work
+//!
+//! However, we do not intend to stop here, since there are other needs that
+//! require carrying information from high to low levels of the app.
+//!
+//! Most importantly, **cancellation signaling** in response to
+//! 1. timeouts (page_service max response time) and
+//! 2. lifecycle requests (detach tenant, delete timeline).
+//!
+//! Related to that, there is sometimes a need to ensure that all tokio tasks spawned
+//! by the transitive callees of a request have finished. The keyword here
+//! is **Structured Concurrency**, and right now, we use `task_mgr` in most places,
+//! `TaskHandle` in some places, and careful code review around `FuturesUnordered`
+//! or `JoinSet` in other places.
+//!
+//! We do not yet have a systematic cancellation story in pageserver, and it is
+//! pretty clear that [`RequestContext`] will be responsible for that.
+//! So, the API already prepares for this role through the
+//! [`RequestContext::detached_child`] and [`RequestContext::attached_child`]  methods.
+//! See their doc comments for details on how we will use them in the future.
+//!
+//! It is not clear whether or how we will enforce Structured Concurrency, and
+//! what role [`RequestContext`] will play there.
+//! So, the API doesn't prepare us for this topic.
+//!
+//! Other future uses of `RequestContext`:
+//! - Communicate compute & IO priorities (user-initiated request vs. background-loop)
+//! - Request IDs for distributed tracing
+//! - Request/Timeline/Tenant-scoped log levels
+//!
+//! RequestContext might look quite different once it supports those features.
+//! Likely, it will have a shape similar to Golang's `context.Context`.
+//!
+//! ### Why A Struct Instead Of Method Parameters
+//!
+//! What's typical about such information is that it needs to be passed down
+//! along the call chain from high level to low level, but few of the functions
+//! in the middle need to understand it.
+//! Further, it is to be expected that we will need to propagate more data
+//! in the future (see the earlier section on future work).
+//! Hence, for functions in the middle of the call chain, we have the following
+//! requirements:
+//! 1. It should be easy to forward the context to callees.
+//! 2. To propagate more data from high-level to low-level code, the functions in
+//!    the middle should not need to be modified.
+//! The solution is to have a container structure ([`RequestContext`]) that
+//! carries the information. Functions that don't care about what's in it
+//! pass it along to callees.
+//!
+//! ### Why Not Task-Local Variables
+//!
+//! One could use task-local variables (the equivalent of thread-local variables)
+//! to address the immediate needs outlined above.
+//! However, we reject task-local variables because:
+//! 1. they are implicit, thereby making it harder to trace the data flow in code
+//!    reviews and during debugging,
+//! 2. they can be mutable, which enables implicit return data flow,
+//! 3. they are restrictive in that code which fans out into multiple tasks,
+//!    or even threads, needs to carefully propagate the state.
+//!
+//! In contrast, information flow with [`RequestContext`] is
+//! 1. always explicit,
+//! 2. strictly uni-directional because RequestContext is immutable,
+//! 3. tangible because a [`RequestContext`] is just a value.
+//!    When creating child activities, regardless of whether it's a task,
+//!    thread, or even an RPC to another service, the value can
+//!    be used like any other argument.
+//!
+//! The solution is that all code paths are infected with precisely one
+//! [`RequestContext`] argument. Functions in the middle of the call chain
+//! only need to pass it on.
+use crate::task_mgr::TaskKind;
+
+// The main structure of this module, see module-level comment.
+pub struct RequestContext {
+    task_kind: TaskKind,
+    download_behavior: DownloadBehavior,
+}
+
+/// Desired behavior if the operation requires an on-demand download
+/// to proceed.
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub enum DownloadBehavior {
+    /// Download the layer file. It can take a while.
+    Download,
+
+    /// Download the layer file, but print a warning to the log. This should be used
+    /// in code where the layer file is expected to already exist locally.
+    Warn,
+
+    /// Return a PageReconstructError::NeedsDownload error
+    Error,
+}
+
+impl RequestContext {
+    /// Create a new RequestContext that has no parent.
+    ///
+    /// The function is called `new` because, once we add children
+    /// to it using `detached_child` or `attached_child`, the context
+    /// form a tree (not implemented yet since cancellation will be
+    /// the first feature that requires a tree).
+    ///
+    /// # Future: Cancellation
+    ///
+    /// The only reason why a context like this one can be canceled is
+    /// because someone explicitly canceled it.
+    /// It has no parent, so it cannot inherit cancellation from there.
+    pub fn new(task_kind: TaskKind, download_behavior: DownloadBehavior) -> Self {
+        RequestContext {
+            task_kind,
+            download_behavior,
+        }
+    }
+
+    /// Create a detached child context for a task that may outlive `self`.
+    ///
+    /// Use this when spawning new background activity that should complete
+    /// even if the current request is canceled.
+    ///
+    /// # Future: Cancellation
+    ///
+    /// Cancellation of `self` will not propagate to the child context returned
+    /// by this method.
+    ///
+    /// # Future: Structured Concurrency
+    ///
+    /// We could add the Future as a parameter to this function, spawn it as a task,
+    /// and pass to the new task the child context as an argument.
+    /// That would be an ergonomic improvement.
+    ///
+    /// We could make new calls to this function fail if `self` is already canceled.
+    pub fn detached_child(&self, task_kind: TaskKind, download_behavior: DownloadBehavior) -> Self {
+        self.child_impl(task_kind, download_behavior)
+    }
+
+    /// Create a child of context `self` for a task that shall not outlive `self`.
+    ///
+    /// Use this when fanning-out work to other async tasks.
+    ///
+    /// # Future: Cancellation
+    ///
+    /// Cancelling a context will propagate to its attached children.
+    ///
+    /// # Future: Structured Concurrency
+    ///
+    /// We could add the Future as a parameter to this function, spawn it as a task,
+    /// and track its `JoinHandle` inside the `RequestContext`.
+    ///
+    /// We could then provide another method to allow waiting for all child tasks
+    /// to finish.
+    ///
+    /// We could make new calls to this function fail if `self` is already canceled.
+    /// Alternatively, we could allow the creation but not spawn the task.
+    /// The method to wait for child tasks would return an error, indicating
+    /// that the child task was not started because the context was canceled.
+    pub fn attached_child(&self) -> Self {
+        self.child_impl(self.task_kind(), self.download_behavior())
+    }
+
+    /// Use this function when you should be creating a child context using
+    /// [`attached_child`] or [`detached_child`], but your caller doesn't provide
+    /// a context and you are unwilling to change all callers to provide one.
+    ///
+    /// Before we add cancellation, we should get rid of this method.
+    pub fn todo_child(task_kind: TaskKind, download_behavior: DownloadBehavior) -> Self {
+        Self::new(task_kind, download_behavior)
+    }
+
+    fn child_impl(&self, task_kind: TaskKind, download_behavior: DownloadBehavior) -> Self {
+        RequestContext {
+            task_kind,
+            download_behavior,
+        }
+    }
+
+    pub fn task_kind(&self) -> TaskKind {
+        self.task_kind
+    }
+
+    pub fn download_behavior(&self) -> DownloadBehavior {
+        self.download_behavior
+    }
+}

pageserver/src/http/openapi_spec.yml

@@ -430,6 +430,13 @@ paths:
         schema:
           type: string
           format: hex
+      - name: inputs_only
+        in: query
+        required: false
+        schema:
+          type: boolean
+        description: |
+          When true, skip calculation and only provide the model inputs (for debugging). Defaults to false.
     get:
       description: |
         Calculate tenant's size, which is a mixture of WAL (bytes) and logical_size (bytes).
@@ -449,8 +456,9 @@ paths:
                     format: hex
                   size:
                     type: integer
+                    nullable: true
                     description: |
-                      Size metric in bytes.
+                      Size metric in bytes or null if inputs_only=true was given.
         "401":
           description: Unauthorized Error
           content:

pageserver/src/http/routes.rs

@@ -3,6 +3,7 @@ use std::sync::Arc;
 use anyhow::{anyhow, Context, Result};
 use hyper::StatusCode;
 use hyper::{Body, Request, Response, Uri};
+use pageserver_api::models::DownloadRemoteLayersTaskSpawnRequest;
 use remote_storage::GenericRemoteStorage;
 use tokio_util::sync::CancellationToken;
 use tracing::*;
@@ -11,8 +12,11 @@ use super::models::{
     StatusResponse, TenantConfigRequest, TenantCreateRequest, TenantCreateResponse, TenantInfo,
     TimelineCreateRequest, TimelineInfo,
 };
+use crate::context::{DownloadBehavior, RequestContext};
 use crate::pgdatadir_mapping::LsnForTimestamp;
+use crate::task_mgr::TaskKind;
 use crate::tenant::config::TenantConfOpt;
+use crate::tenant::mgr::TenantMapInsertError;
 use crate::tenant::{PageReconstructError, Timeline};
 use crate::{config::PageServerConf, tenant::mgr};
 use utils::{
@@ -80,18 +84,41 @@ fn check_permission(request: &Request<Body>, tenant_id: Option<TenantId>) -> Res
 fn apierror_from_prerror(err: PageReconstructError) -> ApiError {
     match err {
         PageReconstructError::Other(err) => ApiError::InternalServerError(err),
+        PageReconstructError::NeedsDownload(_, _) => {
+            // This shouldn't happen, because we use a RequestContext that requests to
+            // download any missing layer files on-demand.
+            ApiError::InternalServerError(anyhow::anyhow!(
+                "would need to download remote layer file"
+            ))
+        }
+        PageReconstructError::Cancelled => {
+            ApiError::InternalServerError(anyhow::anyhow!("request was cancelled"))
+        }
         PageReconstructError::WalRedo(err) => {
             ApiError::InternalServerError(anyhow::Error::new(err))
         }
     }
 }
 
+fn apierror_from_tenant_map_insert_error(e: TenantMapInsertError) -> ApiError {
+    match e {
+        TenantMapInsertError::StillInitializing | TenantMapInsertError::ShuttingDown => {
+            ApiError::InternalServerError(anyhow::Error::new(e))
+        }
+        TenantMapInsertError::TenantAlreadyExists(id, state) => {
+            ApiError::Conflict(format!("tenant {id} already exists, state: {state:?}"))
+        }
+        TenantMapInsertError::Closure(e) => ApiError::InternalServerError(e),
+    }
+}
+
 // Helper function to construct a TimelineInfo struct for a timeline
 async fn build_timeline_info(
     timeline: &Arc<Timeline>,
     include_non_incremental_logical_size: bool,
+    ctx: &RequestContext,
 ) -> anyhow::Result<TimelineInfo> {
-    let mut info = build_timeline_info_common(timeline)?;
+    let mut info = build_timeline_info_common(timeline, ctx)?;
     if include_non_incremental_logical_size {
         // XXX we should be using spawn_ondemand_logical_size_calculation here.
         // Otherwise, if someone deletes the timeline / detaches the tenant while
@@ -101,6 +128,7 @@ async fn build_timeline_info(
                 .get_current_logical_size_non_incremental(
                     info.last_record_lsn,
                     CancellationToken::new(),
+                    ctx,
                 )
                 .await?,
         );
@@ -108,7 +136,10 @@ async fn build_timeline_info(
     Ok(info)
 }
 
-fn build_timeline_info_common(timeline: &Arc<Timeline>) -> anyhow::Result<TimelineInfo> {
+fn build_timeline_info_common(
+    timeline: &Arc<Timeline>,
+    ctx: &RequestContext,
+) -> anyhow::Result<TimelineInfo> {
     let last_record_lsn = timeline.get_last_record_lsn();
     let (wal_source_connstr, last_received_msg_lsn, last_received_msg_ts) = {
         let guard = timeline.last_received_wal.lock().unwrap();
@@ -128,7 +159,7 @@ fn build_timeline_info_common(timeline: &Arc<Timeline>) -> anyhow::Result<Timeli
         Lsn(0) => None,
         lsn @ Lsn(_) => Some(lsn),
     };
-    let current_logical_size = match timeline.get_current_logical_size() {
+    let current_logical_size = match timeline.get_current_logical_size(ctx) {
         Ok((size, _)) => Some(size),
         Err(err) => {
             error!("Timeline info creation failed to get current logical size: {err:?}");
@@ -179,6 +210,8 @@ async fn timeline_create_handler(mut request: Request<Body>) -> Result<Response<
         .new_timeline_id
         .unwrap_or_else(TimelineId::generate);
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Error);
+
     let tenant = mgr::get_tenant(tenant_id, true)
         .await
         .map_err(ApiError::NotFound)?;
@@ -186,13 +219,14 @@ async fn timeline_create_handler(mut request: Request<Body>) -> Result<Response<
         new_timeline_id,
         request_data.ancestor_timeline_id.map(TimelineId::from),
         request_data.ancestor_start_lsn,
-        request_data.pg_version.unwrap_or(crate::DEFAULT_PG_VERSION)
+        request_data.pg_version.unwrap_or(crate::DEFAULT_PG_VERSION),
+        &ctx,
     )
     .instrument(info_span!("timeline_create", tenant = %tenant_id, new_timeline = ?request_data.new_timeline_id, timeline_id = %new_timeline_id, lsn=?request_data.ancestor_start_lsn, pg_version=?request_data.pg_version))
     .await {
         Ok(Some(new_timeline)) => {
             // Created. Construct a TimelineInfo for it.
-            let timeline_info = build_timeline_info_common(&new_timeline)
+            let timeline_info = build_timeline_info_common(&new_timeline, &ctx)
                 .map_err(ApiError::InternalServerError)?;
             json_response(StatusCode::CREATED, timeline_info)
         }
@@ -207,6 +241,8 @@ async fn timeline_list_handler(request: Request<Body>) -> Result<Response<Body>,
         query_param_present(&request, "include-non-incremental-logical-size");
     check_permission(&request, Some(tenant_id))?;
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
+
     let response_data = async {
         let tenant = mgr::get_tenant(tenant_id, true)
             .await
@@ -216,7 +252,7 @@ async fn timeline_list_handler(request: Request<Body>) -> Result<Response<Body>,
         let mut response_data = Vec::with_capacity(timelines.len());
         for timeline in timelines {
             let timeline_info =
-                build_timeline_info(&timeline, include_non_incremental_logical_size)
+                build_timeline_info(&timeline, include_non_incremental_logical_size, &ctx)
                     .await
                     .context(
                         "Failed to convert tenant timeline {timeline_id} into the local one: {e:?}",
@@ -238,11 +274,7 @@ fn query_param_present(request: &Request<Body>, param: &str) -> bool {
     request
         .uri()
         .query()
-        .map(|v| {
-            url::form_urlencoded::parse(v.as_bytes())
-                .into_owned()
-                .any(|(p, _)| p == param)
-        })
+        .map(|v| url::form_urlencoded::parse(v.as_bytes()).any(|(p, _)| p == param))
         .unwrap_or(false)
 }
 
@@ -251,13 +283,12 @@ fn get_query_param(request: &Request<Body>, param_name: &str) -> Result<String,
         Err(ApiError::BadRequest(anyhow!("empty query in request"))),
         |v| {
             url::form_urlencoded::parse(v.as_bytes())
-                .into_owned()
                 .find(|(k, _)| k == param_name)
                 .map_or(
                     Err(ApiError::BadRequest(anyhow!(
                         "no {param_name} specified in query parameters"
                     ))),
-                    |(_, v)| Ok(v),
+                    |(_, v)| Ok(v.into_owned()),
                 )
         },
     )
@@ -270,6 +301,9 @@ async fn timeline_detail_handler(request: Request<Body>) -> Result<Response<Body
         query_param_present(&request, "include-non-incremental-logical-size");
     check_permission(&request, Some(tenant_id))?;
 
+    // Logical size calculation needs downloading.
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
+
     let timeline_info = async {
         let tenant = mgr::get_tenant(tenant_id, true)
             .await
@@ -279,10 +313,11 @@ async fn timeline_detail_handler(request: Request<Body>) -> Result<Response<Body
             .get_timeline(timeline_id, false)
             .map_err(ApiError::NotFound)?;
 
-        let timeline_info = build_timeline_info(&timeline, include_non_incremental_logical_size)
-            .await
-            .context("Failed to get local timeline info: {e:#}")
-            .map_err(ApiError::InternalServerError)?;
+        let timeline_info =
+            build_timeline_info(&timeline, include_non_incremental_logical_size, &ctx)
+                .await
+                .context("get local timeline info")
+                .map_err(ApiError::InternalServerError)?;
 
         Ok::<_, ApiError>(timeline_info)
     }
@@ -303,12 +338,13 @@ async fn get_lsn_by_timestamp_handler(request: Request<Body>) -> Result<Response
         .map_err(ApiError::BadRequest)?;
     let timestamp_pg = postgres_ffi::to_pg_timestamp(timestamp);
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
     let timeline = mgr::get_tenant(tenant_id, true)
         .await
         .and_then(|tenant| tenant.get_timeline(timeline_id, true))
         .map_err(ApiError::NotFound)?;
     let result = timeline
-        .find_lsn_for_timestamp(timestamp_pg)
+        .find_lsn_for_timestamp(timestamp_pg, &ctx)
         .await
         .map_err(apierror_from_prerror)?;
 
@@ -326,16 +362,17 @@ async fn tenant_attach_handler(request: Request<Body>) -> Result<Response<Body>,
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Warn);
+
     info!("Handling tenant attach {tenant_id}");
 
     let state = get_state(&request);
 
     if let Some(remote_storage) = &state.remote_storage {
-        // FIXME: distinguish between "Tenant already exists" and other errors
-        mgr::attach_tenant(state.conf, tenant_id, remote_storage.clone())
+        mgr::attach_tenant(state.conf, tenant_id, remote_storage.clone(), &ctx)
             .instrument(info_span!("tenant_attach", tenant = %tenant_id))
             .await
-            .map_err(ApiError::InternalServerError)?;
+            .map_err(apierror_from_tenant_map_insert_error)?;
     } else {
         return Err(ApiError::BadRequest(anyhow!(
             "attach_tenant is not possible because pageserver was configured without remote storage"
@@ -350,7 +387,9 @@ async fn timeline_delete_handler(request: Request<Body>) -> Result<Response<Body
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
 
-    mgr::delete_timeline(tenant_id, timeline_id)
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Warn);
+
+    mgr::delete_timeline(tenant_id, timeline_id, &ctx)
         .instrument(info_span!("timeline_delete", tenant = %tenant_id, timeline = %timeline_id))
         .await
         // FIXME: Errors from `delete_timeline` can occur for a number of reasons, incuding both
@@ -381,11 +420,13 @@ async fn tenant_load_handler(request: Request<Body>) -> Result<Response<Body>, A
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Warn);
+
     let state = get_state(&request);
-    mgr::load_tenant(state.conf, tenant_id, state.remote_storage.clone())
+    mgr::load_tenant(state.conf, tenant_id, state.remote_storage.clone(), &ctx)
         .instrument(info_span!("load", tenant = %tenant_id))
         .await
-        .map_err(ApiError::InternalServerError)?;
+        .map_err(apierror_from_tenant_map_insert_error)?;
 
     json_response(StatusCode::ACCEPTED, ())
 }
@@ -412,6 +453,8 @@ async fn tenant_list_handler(request: Request<Body>) -> Result<Response<Body>, A
     let response_data = mgr::list_tenants()
         .instrument(info_span!("tenant_list"))
         .await
+        .map_err(anyhow::Error::new)
+        .map_err(ApiError::InternalServerError)?
         .iter()
         .map(|(id, state)| TenantInfo {
             id: *id,
@@ -452,21 +495,40 @@ async fn tenant_status(request: Request<Body>) -> Result<Response<Body>, ApiErro
     json_response(StatusCode::OK, tenant_info)
 }
 
+/// HTTP endpoint to query the current tenant_size of a tenant.
+///
+/// This is not used by consumption metrics under [`crate::consumption_metrics`], but can be used
+/// to debug any of the calculations. Requires `tenant_id` request parameter, supports
+/// `inputs_only=true|false` (default false) which supports debugging failure to calculate model
+/// values.
 async fn tenant_size_handler(request: Request<Body>) -> Result<Response<Body>, ApiError> {
     let tenant_id: TenantId = parse_request_param(&request, "tenant_id")?;
     check_permission(&request, Some(tenant_id))?;
 
+    let inputs_only = if query_param_present(&request, "inputs_only") {
+        get_query_param(&request, "inputs_only")?
+            .parse()
+            .map_err(|_| ApiError::BadRequest(anyhow!("failed to parse inputs_only")))?
+    } else {
+        false
+    };
+
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
     let tenant = mgr::get_tenant(tenant_id, true)
         .await
         .map_err(ApiError::InternalServerError)?;
 
-    // this can be long operation, it currently is not backed by any request coalescing or similar
+    // this can be long operation
     let inputs = tenant
-        .gather_size_inputs()
+        .gather_size_inputs(&ctx)
         .await
         .map_err(ApiError::InternalServerError)?;
 
-    let size = inputs.calculate().map_err(ApiError::InternalServerError)?;
+    let size = if !inputs_only {
+        Some(inputs.calculate().map_err(ApiError::InternalServerError)?)
+    } else {
+        None
+    };
 
     /// Private response type with the additional "unstable" `inputs` field.
     ///
@@ -478,7 +540,9 @@ async fn tenant_size_handler(request: Request<Body>) -> Result<Response<Body>, A
         #[serde_as(as = "serde_with::DisplayFromStr")]
         id: TenantId,
         /// Size is a mixture of WAL and logical size, so the unit is bytes.
-        size: u64,
+        ///
+        /// Will be none if `?inputs_only=true` was given.
+        size: Option<u64>,
         inputs: crate::tenant::size::ModelInputs,
     }
 
@@ -505,6 +569,8 @@ fn bad_duration<'a>(field_name: &'static str, value: &'a str) -> impl 'a + Fn()
 async fn tenant_create_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
     check_permission(&request, None)?;
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Warn);
+
     let request_data: TenantCreateRequest = json_request(&mut request).await?;
 
     let mut tenant_conf = TenantConfOpt::default();
@@ -582,34 +648,28 @@ async fn tenant_create_handler(mut request: Request<Body>) -> Result<Response<Bo
         tenant_conf,
         target_tenant_id,
         state.remote_storage.clone(),
+        &ctx,
     )
     .instrument(info_span!("tenant_create", tenant = ?target_tenant_id))
     .await
-    // FIXME: `create_tenant` can fail from both user and internal errors. Replace this
-    // with better error handling once the type permits it
-    .map_err(ApiError::InternalServerError)?;
+    .map_err(apierror_from_tenant_map_insert_error)?;
 
-    Ok(match new_tenant {
-        Some(tenant) => {
-            // We created the tenant. Existing API semantics are that the tenant
-            // is Active when this function returns.
-            if let res @ Err(_) = tenant.wait_to_become_active().await {
-                // This shouldn't happen because we just created the tenant directory
-                // in tenant::mgr::create_tenant, and there aren't any remote timelines
-                // to load, so, nothing can really fail during load.
-                // Don't do cleanup because we don't know how we got here.
-                // The tenant will likely be in `Broken` state and subsequent
-                // calls will fail.
-                res.context("created tenant failed to become active")
-                    .map_err(ApiError::InternalServerError)?;
-            }
-            json_response(
-                StatusCode::CREATED,
-                TenantCreateResponse(tenant.tenant_id()),
-            )?
-        }
-        None => json_response(StatusCode::CONFLICT, ())?,
-    })
+    // We created the tenant. Existing API semantics are that the tenant
+    // is Active when this function returns.
+    if let res @ Err(_) = new_tenant.wait_to_become_active().await {
+        // This shouldn't happen because we just created the tenant directory
+        // in tenant::mgr::create_tenant, and there aren't any remote timelines
+        // to load, so, nothing can really fail during load.
+        // Don't do cleanup because we don't know how we got here.
+        // The tenant will likely be in `Broken` state and subsequent
+        // calls will fail.
+        res.context("created tenant failed to become active")
+            .map_err(ApiError::InternalServerError)?;
+    }
+    json_response(
+        StatusCode::CREATED,
+        TenantCreateResponse(new_tenant.tenant_id()),
+    )
 }
 
 async fn tenant_config_handler(mut request: Request<Body>) -> Result<Response<Body>, ApiError> {
@@ -731,7 +791,8 @@ async fn timeline_gc_handler(mut request: Request<Body>) -> Result<Response<Body
 
     let gc_req: TimelineGcRequest = json_request(&mut request).await?;
 
-    let wait_task_done = mgr::immediate_gc(tenant_id, timeline_id, gc_req).await?;
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
+    let wait_task_done = mgr::immediate_gc(tenant_id, timeline_id, gc_req, &ctx).await?;
     let gc_result = wait_task_done
         .await
         .context("wait for gc task")
@@ -748,7 +809,8 @@ async fn timeline_compact_handler(request: Request<Body>) -> Result<Response<Bod
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
 
-    let result_receiver = mgr::immediate_compact(tenant_id, timeline_id)
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
+    let result_receiver = mgr::immediate_compact(tenant_id, timeline_id, &ctx)
         .await
         .context("spawn compaction task")
         .map_err(ApiError::InternalServerError)?;
@@ -769,6 +831,7 @@ async fn timeline_checkpoint_handler(request: Request<Body>) -> Result<Response<
     let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
     check_permission(&request, Some(tenant_id))?;
 
+    let ctx = RequestContext::new(TaskKind::MgmtRequest, DownloadBehavior::Download);
     let tenant = mgr::get_tenant(tenant_id, true)
         .await
         .map_err(ApiError::NotFound)?;
@@ -780,7 +843,7 @@ async fn timeline_checkpoint_handler(request: Request<Body>) -> Result<Response<
         .await
         .map_err(ApiError::InternalServerError)?;
     timeline
-        .compact()
+        .compact(&ctx)
         .await
         .map_err(ApiError::InternalServerError)?;
 
@@ -788,10 +851,11 @@ async fn timeline_checkpoint_handler(request: Request<Body>) -> Result<Response<
 }
 
 async fn timeline_download_remote_layers_handler_post(
-    request: Request<Body>,
+    mut request: Request<Body>,
 ) -> 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 body: DownloadRemoteLayersTaskSpawnRequest = json_request(&mut request).await?;
     check_permission(&request, Some(tenant_id))?;
 
     let tenant = mgr::get_tenant(tenant_id, true)
@@ -800,7 +864,7 @@ async fn timeline_download_remote_layers_handler_post(
     let timeline = tenant
         .get_timeline(timeline_id, true)
         .map_err(ApiError::NotFound)?;
-    match timeline.spawn_download_all_remote_layers().await {
+    match timeline.spawn_download_all_remote_layers(body).await {
         Ok(st) => json_response(StatusCode::ACCEPTED, st),
         Err(st) => json_response(StatusCode::CONFLICT, st),
     }

pageserver/src/import_datadir.rs

@@ -12,6 +12,7 @@ use tokio_tar::Archive;
 use tracing::*;
 use walkdir::WalkDir;
 
+use crate::context::RequestContext;
 use crate::pgdatadir_mapping::*;
 use crate::tenant::Timeline;
 use crate::walingest::WalIngest;
@@ -47,6 +48,7 @@ pub async fn import_timeline_from_postgres_datadir(
     tline: &Timeline,
     pgdata_path: &Path,
     pgdata_lsn: Lsn,
+    ctx: &RequestContext,
 ) -> Result<()> {
     let mut pg_control: Option<ControlFileData> = None;
 
@@ -69,7 +71,7 @@ pub async fn import_timeline_from_postgres_datadir(
             let mut file = tokio::fs::File::open(absolute_path).await?;
             let len = metadata.len() as usize;
             if let Some(control_file) =
-                import_file(&mut modification, relative_path, &mut file, len).await?
+                import_file(&mut modification, relative_path, &mut file, len, ctx).await?
             {
                 pg_control = Some(control_file);
             }
@@ -99,6 +101,7 @@ pub async fn import_timeline_from_postgres_datadir(
         tline,
         Lsn(pg_control.checkPointCopy.redo),
         pgdata_lsn,
+        ctx,
     )
     .await?;
 
@@ -113,6 +116,7 @@ async fn import_rel(
     dboid: Oid,
     reader: &mut (impl AsyncRead + Send + Sync + Unpin),
     len: usize,
+    ctx: &RequestContext,
 ) -> anyhow::Result<()> {
     // Does it look like a relation file?
     trace!("importing rel file {}", path.display());
@@ -147,7 +151,10 @@ async fn import_rel(
     // FIXME: use proper error type for this, instead of parsing the error message.
     // Or better yet, keep track of which relations we've already created
     // https://github.com/neondatabase/neon/issues/3309
-    if let Err(e) = modification.put_rel_creation(rel, nblocks as u32).await {
+    if let Err(e) = modification
+        .put_rel_creation(rel, nblocks as u32, ctx)
+        .await
+    {
         if e.to_string().contains("already exists") {
             debug!("relation {} already exists. we must be extending it", rel);
         } else {
@@ -182,7 +189,7 @@ async fn import_rel(
     //
     // If we process rel segments out of order,
     // put_rel_extend will skip the update.
-    modification.put_rel_extend(rel, blknum).await?;
+    modification.put_rel_extend(rel, blknum, ctx).await?;
 
     Ok(())
 }
@@ -195,6 +202,7 @@ async fn import_slru(
     path: &Path,
     reader: &mut (impl AsyncRead + Send + Sync + Unpin),
     len: usize,
+    ctx: &RequestContext,
 ) -> anyhow::Result<()> {
     info!("importing slru file {path:?}");
 
@@ -211,7 +219,7 @@ async fn import_slru(
     ensure!(nblocks <= pg_constants::SLRU_PAGES_PER_SEGMENT as usize);
 
     modification
-        .put_slru_segment_creation(slru, segno, nblocks as u32)
+        .put_slru_segment_creation(slru, segno, nblocks as u32, ctx)
         .await?;
 
     let mut rpageno = 0;
@@ -252,15 +260,15 @@ async fn import_wal(
     tline: &Timeline,
     startpoint: Lsn,
     endpoint: Lsn,
+    ctx: &RequestContext,
 ) -> anyhow::Result<()> {
-    use std::io::Read;
     let mut waldecoder = WalStreamDecoder::new(startpoint, tline.pg_version);
 
     let mut segno = startpoint.segment_number(WAL_SEGMENT_SIZE);
     let mut offset = startpoint.segment_offset(WAL_SEGMENT_SIZE);
     let mut last_lsn = startpoint;
 
-    let mut walingest = WalIngest::new(tline, startpoint).await?;
+    let mut walingest = WalIngest::new(tline, startpoint, ctx).await?;
 
     while last_lsn <= endpoint {
         // FIXME: assume postgresql tli 1 for now
@@ -283,6 +291,7 @@ async fn import_wal(
             file.seek(std::io::SeekFrom::Start(offset as u64))?;
         }
 
+        use std::io::Read;
         let nread = file.read_to_end(&mut buf)?;
         if nread != WAL_SEGMENT_SIZE - offset {
             // Maybe allow this for .partial files?
@@ -297,7 +306,7 @@ async fn import_wal(
         while last_lsn <= endpoint {
             if let Some((lsn, recdata)) = waldecoder.poll_decode()? {
                 walingest
-                    .ingest_record(recdata, lsn, &mut modification, &mut decoded)
+                    .ingest_record(recdata, lsn, &mut modification, &mut decoded, ctx)
                     .await?;
                 last_lsn = lsn;
 
@@ -326,6 +335,7 @@ pub async fn import_basebackup_from_tar(
     tline: &Timeline,
     reader: &mut (impl AsyncRead + Send + Sync + Unpin),
     base_lsn: Lsn,
+    ctx: &RequestContext,
 ) -> Result<()> {
     info!("importing base at {base_lsn}");
     let mut modification = tline.begin_modification(base_lsn);
@@ -344,7 +354,7 @@ pub async fn import_basebackup_from_tar(
         match header.entry_type() {
             tokio_tar::EntryType::Regular => {
                 if let Some(res) =
-                    import_file(&mut modification, file_path.as_ref(), &mut entry, len).await?
+                    import_file(&mut modification, file_path.as_ref(), &mut entry, len, ctx).await?
                 {
                     // We found the pg_control file.
                     pg_control = Some(res);
@@ -376,13 +386,14 @@ pub async fn import_wal_from_tar(
     reader: &mut (impl AsyncRead + Send + Sync + Unpin),
     start_lsn: Lsn,
     end_lsn: Lsn,
+    ctx: &RequestContext,
 ) -> Result<()> {
     // Set up walingest mutable state
     let mut waldecoder = WalStreamDecoder::new(start_lsn, tline.pg_version);
     let mut segno = start_lsn.segment_number(WAL_SEGMENT_SIZE);
     let mut offset = start_lsn.segment_offset(WAL_SEGMENT_SIZE);
     let mut last_lsn = start_lsn;
-    let mut walingest = WalIngest::new(tline, start_lsn).await?;
+    let mut walingest = WalIngest::new(tline, start_lsn, ctx).await?;
 
     // Ingest wal until end_lsn
     info!("importing wal until {}", end_lsn);
@@ -431,7 +442,7 @@ pub async fn import_wal_from_tar(
         while last_lsn <= end_lsn {
             if let Some((lsn, recdata)) = waldecoder.poll_decode()? {
                 walingest
-                    .ingest_record(recdata, lsn, &mut modification, &mut decoded)
+                    .ingest_record(recdata, lsn, &mut modification, &mut decoded, ctx)
                     .await?;
                 last_lsn = lsn;
 
@@ -466,6 +477,7 @@ async fn import_file(
     file_path: &Path,
     reader: &mut (impl AsyncRead + Send + Sync + Unpin),
     len: usize,
+    ctx: &RequestContext,
 ) -> Result<Option<ControlFileData>> {
     let file_name = match file_path.file_name() {
         Some(name) => name.to_string_lossy(),
@@ -498,14 +510,16 @@ async fn import_file(
             }
             "pg_filenode.map" => {
                 let bytes = read_all_bytes(reader).await?;
-                modification.put_relmap_file(spcnode, dbnode, bytes).await?;
+                modification
+                    .put_relmap_file(spcnode, dbnode, bytes, ctx)
+                    .await?;
                 debug!("imported relmap file")
             }
             "PG_VERSION" => {
                 debug!("ignored PG_VERSION file");
             }
             _ => {
-                import_rel(modification, file_path, spcnode, dbnode, reader, len).await?;
+                import_rel(modification, file_path, spcnode, dbnode, reader, len, ctx).await?;
                 debug!("imported rel creation");
             }
         }
@@ -521,38 +535,40 @@ async fn import_file(
         match file_name.as_ref() {
             "pg_filenode.map" => {
                 let bytes = read_all_bytes(reader).await?;
-                modification.put_relmap_file(spcnode, dbnode, bytes).await?;
+                modification
+                    .put_relmap_file(spcnode, dbnode, bytes, ctx)
+                    .await?;
                 debug!("imported relmap file")
             }
             "PG_VERSION" => {
                 debug!("ignored PG_VERSION file");
             }
             _ => {
-                import_rel(modification, file_path, spcnode, dbnode, reader, len).await?;
+                import_rel(modification, file_path, spcnode, dbnode, reader, len, ctx).await?;
                 debug!("imported rel creation");
             }
         }
     } else if file_path.starts_with("pg_xact") {
         let slru = SlruKind::Clog;
 
-        import_slru(modification, slru, file_path, reader, len).await?;
+        import_slru(modification, slru, file_path, reader, len, ctx).await?;
         debug!("imported clog slru");
     } else if file_path.starts_with("pg_multixact/offsets") {
         let slru = SlruKind::MultiXactOffsets;
 
-        import_slru(modification, slru, file_path, reader, len).await?;
+        import_slru(modification, slru, file_path, reader, len, ctx).await?;
         debug!("imported multixact offsets slru");
     } else if file_path.starts_with("pg_multixact/members") {
         let slru = SlruKind::MultiXactMembers;
 
-        import_slru(modification, slru, file_path, reader, len).await?;
+        import_slru(modification, slru, file_path, reader, len, ctx).await?;
         debug!("imported multixact members slru");
     } else if file_path.starts_with("pg_twophase") {
         let xid = u32::from_str_radix(file_name.as_ref(), 16)?;
 
         let bytes = read_all_bytes(reader).await?;
         modification
-            .put_twophase_file(xid, Bytes::copy_from_slice(&bytes[..]))
+            .put_twophase_file(xid, Bytes::copy_from_slice(&bytes[..]), ctx)
             .await?;
         debug!("imported twophase file");
     } else if file_path.starts_with("pg_wal") {

pageserver/src/lib.rs

@@ -2,6 +2,7 @@ mod auth;
 pub mod basebackup;
 pub mod config;
 pub mod consumption_metrics;
+pub mod context;
 pub mod http;
 pub mod import_datadir;
 pub mod keyspace;

pageserver/src/page_service.rs

@@ -13,6 +13,7 @@ use anyhow::Context;
 use bytes::Buf;
 use bytes::Bytes;
 use futures::{Stream, StreamExt};
+use pageserver_api::models::TenantState;
 use pageserver_api::models::{
     PagestreamBeMessage, PagestreamDbSizeRequest, PagestreamDbSizeResponse,
     PagestreamErrorResponse, PagestreamExistsRequest, PagestreamExistsResponse,
@@ -30,19 +31,19 @@ use std::sync::Arc;
 use std::time::Duration;
 use tracing::*;
 use utils::id::ConnectionId;
-use utils::postgres_backend_async::QueryError;
 use utils::{
     auth::{Claims, JwtAuth, Scope},
     id::{TenantId, TimelineId},
     lsn::Lsn,
     postgres_backend::AuthType,
-    postgres_backend_async::{self, PostgresBackend},
+    postgres_backend_async::{self, is_expected_io_error, PostgresBackend, QueryError},
     simple_rcu::RcuReadGuard,
 };
 
 use crate::auth::check_permission;
 use crate::basebackup;
 use crate::config::PageServerConf;
+use crate::context::{DownloadBehavior, RequestContext};
 use crate::import_datadir::import_wal_from_tar;
 use crate::metrics::{LIVE_CONNECTIONS_COUNT, SMGR_QUERY_TIME};
 use crate::task_mgr;
@@ -123,6 +124,7 @@ pub async fn libpq_listener_main(
     auth: Option<Arc<JwtAuth>>,
     listener: TcpListener,
     auth_type: AuthType,
+    listener_ctx: RequestContext,
 ) -> anyhow::Result<()> {
     listener.set_nonblocking(true)?;
     let tokio_listener = tokio::net::TcpListener::from_std(listener)?;
@@ -146,6 +148,9 @@ pub async fn libpq_listener_main(
                 debug!("accepted connection from {}", peer_addr);
                 let local_auth = auth.clone();
 
+                let connection_ctx = listener_ctx
+                    .detached_child(TaskKind::PageRequestHandler, DownloadBehavior::Download);
+
                 // PageRequestHandler tasks are not associated with any particular
                 // timeline in the task manager. In practice most connections will
                 // only deal with a particular timeline, but we don't know which one
@@ -157,7 +162,7 @@ pub async fn libpq_listener_main(
                     None,
                     "serving compute connection task",
                     false,
-                    page_service_conn_main(conf, local_auth, socket, auth_type),
+                    page_service_conn_main(conf, local_auth, socket, auth_type, connection_ctx),
                 );
             }
             Err(err) => {
@@ -177,6 +182,7 @@ async fn page_service_conn_main(
     auth: Option<Arc<JwtAuth>>,
     socket: tokio::net::TcpStream,
     auth_type: AuthType,
+    connection_ctx: RequestContext,
 ) -> anyhow::Result<()> {
     // Immediately increment the gauge, then create a job to decrement it on task exit.
     // One of the pros of `defer!` is that this will *most probably*
@@ -191,24 +197,24 @@ async fn page_service_conn_main(
         .set_nodelay(true)
         .context("could not set TCP_NODELAY")?;
 
-    let mut conn_handler = PageServerHandler::new(conf, auth);
+    // XXX: pgbackend.run() should take the connection_ctx,
+    // and create a child per-query context when it invokes process_query.
+    // But it's in a shared crate, so, we store connection_ctx inside PageServerHandler
+    // and create the per-query context in process_query ourselves.
+    let mut conn_handler = PageServerHandler::new(conf, auth, connection_ctx);
     let pgbackend = PostgresBackend::new(socket, auth_type, None)?;
 
-    let result = pgbackend
+    match pgbackend
         .run(&mut conn_handler, task_mgr::shutdown_watcher)
-        .await;
-    match result {
+        .await
+    {
         Ok(()) => {
             // we've been requested to shut down
             Ok(())
         }
         Err(QueryError::Disconnected(ConnectionError::Socket(io_error))) => {
-            // `ConnectionReset` error happens when the Postgres client closes the connection.
-            // As this disconnection happens quite often and is expected,
-            // we decided to downgrade the logging level to `INFO`.
-            // See: https://github.com/neondatabase/neon/issues/1683.
-            if io_error.kind() == io::ErrorKind::ConnectionReset {
-                info!("Postgres client disconnected");
+            if is_expected_io_error(&io_error) {
+                info!("Postgres client disconnected ({io_error})");
                 Ok(())
             } else {
                 Err(io_error).context("Postgres connection error")
@@ -255,30 +261,42 @@ struct PageServerHandler {
     _conf: &'static PageServerConf,
     auth: Option<Arc<JwtAuth>>,
     claims: Option<Claims>,
+
+    /// The context created for the lifetime of the connection
+    /// services by this PageServerHandler.
+    /// For each query received over the connection,
+    /// `process_query` creates a child context from this one.
+    connection_ctx: RequestContext,
 }
 
 impl PageServerHandler {
-    pub fn new(conf: &'static PageServerConf, auth: Option<Arc<JwtAuth>>) -> Self {
+    pub fn new(
+        conf: &'static PageServerConf,
+        auth: Option<Arc<JwtAuth>>,
+        connection_ctx: RequestContext,
+    ) -> Self {
         PageServerHandler {
             _conf: conf,
             auth,
             claims: None,
+            connection_ctx,
         }
     }
 
-    #[instrument(skip(self, pgb))]
+    #[instrument(skip(self, pgb, ctx))]
     async fn handle_pagerequests(
         &self,
         pgb: &mut PostgresBackend,
         tenant_id: TenantId,
         timeline_id: TimelineId,
+        ctx: RequestContext,
     ) -> anyhow::Result<()> {
         // NOTE: pagerequests handler exits when connection is closed,
         //       so there is no need to reset the association
         task_mgr::associate_with(Some(tenant_id), Some(timeline_id));
 
         // Make request tracer if needed
-        let tenant = get_active_tenant_with_timeout(tenant_id).await?;
+        let tenant = get_active_tenant_with_timeout(tenant_id, &ctx).await?;
         let mut tracer = if tenant.get_trace_read_requests() {
             let connection_id = ConnectionId::generate();
             let path = tenant
@@ -329,22 +347,27 @@ impl PageServerHandler {
 
             let neon_fe_msg = PagestreamFeMessage::parse(&mut copy_data_bytes.reader())?;
 
+            // TODO: We could create a new per-request context here, with unique ID.
+            // Currently we use the same per-timeline context for all requests
+
             let response = match neon_fe_msg {
                 PagestreamFeMessage::Exists(req) => {
                     let _timer = metrics.get_rel_exists.start_timer();
-                    self.handle_get_rel_exists_request(&timeline, &req).await
+                    self.handle_get_rel_exists_request(&timeline, &req, &ctx)
+                        .await
                 }
                 PagestreamFeMessage::Nblocks(req) => {
                     let _timer = metrics.get_rel_size.start_timer();
-                    self.handle_get_nblocks_request(&timeline, &req).await
+                    self.handle_get_nblocks_request(&timeline, &req, &ctx).await
                 }
                 PagestreamFeMessage::GetPage(req) => {
                     let _timer = metrics.get_page_at_lsn.start_timer();
-                    self.handle_get_page_at_lsn_request(&timeline, &req).await
+                    self.handle_get_page_at_lsn_request(&timeline, &req, &ctx)
+                        .await
                 }
                 PagestreamFeMessage::DbSize(req) => {
                     let _timer = metrics.get_db_size.start_timer();
-                    self.handle_db_size_request(&timeline, &req).await
+                    self.handle_db_size_request(&timeline, &req, &ctx).await
                 }
             };
 
@@ -363,7 +386,8 @@ impl PageServerHandler {
         Ok(())
     }
 
-    #[instrument(skip(self, pgb))]
+    #[allow(clippy::too_many_arguments)]
+    #[instrument(skip(self, pgb, ctx))]
     async fn handle_import_basebackup(
         &self,
         pgb: &mut PostgresBackend,
@@ -372,12 +396,13 @@ impl PageServerHandler {
         base_lsn: Lsn,
         _end_lsn: Lsn,
         pg_version: u32,
+        ctx: RequestContext,
     ) -> Result<(), QueryError> {
         task_mgr::associate_with(Some(tenant_id), Some(timeline_id));
         // Create empty timeline
         info!("creating new timeline");
-        let tenant = get_active_tenant_with_timeout(tenant_id).await?;
-        let timeline = tenant.create_empty_timeline(timeline_id, base_lsn, pg_version)?;
+        let tenant = get_active_tenant_with_timeout(tenant_id, &ctx).await?;
+        let timeline = tenant.create_empty_timeline(timeline_id, base_lsn, pg_version, &ctx)?;
 
         // TODO mark timeline as not ready until it reaches end_lsn.
         // We might have some wal to import as well, and we should prevent compute
@@ -396,7 +421,7 @@ impl PageServerHandler {
 
         let mut copyin_stream = Box::pin(copyin_stream(pgb));
         timeline
-            .import_basebackup_from_tar(&mut copyin_stream, base_lsn)
+            .import_basebackup_from_tar(&mut copyin_stream, base_lsn, &ctx)
             .await?;
 
         // Drain the rest of the Copy data
@@ -418,7 +443,7 @@ impl PageServerHandler {
         Ok(())
     }
 
-    #[instrument(skip(self, pgb))]
+    #[instrument(skip(self, pgb, ctx))]
     async fn handle_import_wal(
         &self,
         pgb: &mut PostgresBackend,
@@ -426,10 +451,11 @@ impl PageServerHandler {
         timeline_id: TimelineId,
         start_lsn: Lsn,
         end_lsn: Lsn,
+        ctx: RequestContext,
     ) -> Result<(), QueryError> {
         task_mgr::associate_with(Some(tenant_id), Some(timeline_id));
 
-        let timeline = get_active_timeline_with_timeout(tenant_id, timeline_id).await?;
+        let timeline = get_active_tenant_timeline(tenant_id, timeline_id, &ctx).await?;
         let last_record_lsn = timeline.get_last_record_lsn();
         if last_record_lsn != start_lsn {
             return Err(QueryError::Other(
@@ -446,7 +472,7 @@ impl PageServerHandler {
         pgb.flush().await?;
         let mut copyin_stream = Box::pin(copyin_stream(pgb));
         let mut reader = tokio_util::io::StreamReader::new(&mut copyin_stream);
-        import_wal_from_tar(&timeline, &mut reader, start_lsn, end_lsn).await?;
+        import_wal_from_tar(&timeline, &mut reader, start_lsn, end_lsn, &ctx).await?;
         info!("wal import complete");
 
         // Drain the rest of the Copy data
@@ -492,6 +518,7 @@ impl PageServerHandler {
         mut lsn: Lsn,
         latest: bool,
         latest_gc_cutoff_lsn: &RcuReadGuard<Lsn>,
+        ctx: &RequestContext,
     ) -> anyhow::Result<Lsn> {
         if latest {
             // Latest page version was requested. If LSN is given, it is a hint
@@ -515,7 +542,7 @@ impl PageServerHandler {
             if lsn <= last_record_lsn {
                 lsn = last_record_lsn;
             } else {
-                timeline.wait_lsn(lsn).await?;
+                timeline.wait_lsn(lsn, ctx).await?;
                 // Since we waited for 'lsn' to arrive, that is now the last
                 // record LSN. (Or close enough for our purposes; the
                 // last-record LSN can advance immediately after we return
@@ -525,7 +552,7 @@ impl PageServerHandler {
             if lsn == Lsn(0) {
                 anyhow::bail!("invalid LSN(0) in request");
             }
-            timeline.wait_lsn(lsn).await?;
+            timeline.wait_lsn(lsn, ctx).await?;
         }
         anyhow::ensure!(
             lsn >= **latest_gc_cutoff_lsn,
@@ -535,52 +562,60 @@ impl PageServerHandler {
         Ok(lsn)
     }
 
-    #[instrument(skip(self, timeline, req), fields(rel = %req.rel, req_lsn = %req.lsn))]
+    #[instrument(skip(self, timeline, req, ctx), fields(rel = %req.rel, req_lsn = %req.lsn))]
     async fn handle_get_rel_exists_request(
         &self,
         timeline: &Timeline,
         req: &PagestreamExistsRequest,
+        ctx: &RequestContext,
     ) -> anyhow::Result<PagestreamBeMessage> {
         let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn)
-            .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;
 
-        let exists = timeline.get_rel_exists(req.rel, lsn, req.latest).await?;
+        let exists = timeline
+            .get_rel_exists(req.rel, lsn, req.latest, ctx)
+            .await?;
 
         Ok(PagestreamBeMessage::Exists(PagestreamExistsResponse {
             exists,
         }))
     }
 
-    #[instrument(skip(self, timeline, req), fields(rel = %req.rel, req_lsn = %req.lsn))]
+    #[instrument(skip(self, timeline, req, ctx), fields(rel = %req.rel, req_lsn = %req.lsn))]
     async fn handle_get_nblocks_request(
         &self,
         timeline: &Timeline,
         req: &PagestreamNblocksRequest,
+        ctx: &RequestContext,
     ) -> anyhow::Result<PagestreamBeMessage> {
         let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn)
-            .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;
 
-        let n_blocks = timeline.get_rel_size(req.rel, lsn, req.latest).await?;
+        let n_blocks = timeline.get_rel_size(req.rel, lsn, req.latest, ctx).await?;
 
         Ok(PagestreamBeMessage::Nblocks(PagestreamNblocksResponse {
             n_blocks,
         }))
     }
 
-    #[instrument(skip(self, timeline, req), fields(dbnode = %req.dbnode, req_lsn = %req.lsn))]
+    #[instrument(skip(self, timeline, req, ctx), fields(dbnode = %req.dbnode, req_lsn = %req.lsn))]
     async fn handle_db_size_request(
         &self,
         timeline: &Timeline,
         req: &PagestreamDbSizeRequest,
+        ctx: &RequestContext,
     ) -> anyhow::Result<PagestreamBeMessage> {
         let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn)
-            .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;
 
         let total_blocks = timeline
-            .get_db_size(DEFAULTTABLESPACE_OID, req.dbnode, lsn, req.latest)
+            .get_db_size(DEFAULTTABLESPACE_OID, req.dbnode, lsn, req.latest, ctx)
             .await?;
         let db_size = total_blocks as i64 * BLCKSZ as i64;
 
@@ -589,15 +624,17 @@ impl PageServerHandler {
         }))
     }
 
-    #[instrument(skip(self, timeline, req), fields(rel = %req.rel, blkno = %req.blkno, req_lsn = %req.lsn))]
+    #[instrument(skip(self, timeline, req, ctx), fields(rel = %req.rel, blkno = %req.blkno, req_lsn = %req.lsn))]
     async fn handle_get_page_at_lsn_request(
         &self,
         timeline: &Timeline,
         req: &PagestreamGetPageRequest,
+        ctx: &RequestContext,
     ) -> anyhow::Result<PagestreamBeMessage> {
         let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
-        let lsn = Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn)
-            .await?;
+        let lsn =
+            Self::wait_or_get_last_lsn(timeline, req.lsn, req.latest, &latest_gc_cutoff_lsn, ctx)
+                .await?;
         /*
         // Add a 1s delay to some requests. The delay helps the requests to
         // hit the race condition from github issue #1047 more easily.
@@ -608,7 +645,7 @@ impl PageServerHandler {
         */
 
         let page = timeline
-            .get_rel_page_at_lsn(req.rel, req.blkno, lsn, req.latest)
+            .get_rel_page_at_lsn(req.rel, req.blkno, lsn, req.latest, ctx)
             .await?;
 
         Ok(PagestreamBeMessage::GetPage(PagestreamGetPageResponse {
@@ -616,23 +653,25 @@ impl PageServerHandler {
         }))
     }
 
-    #[instrument(skip(self, pgb))]
+    #[allow(clippy::too_many_arguments)]
+    #[instrument(skip(self, pgb, ctx))]
     async fn handle_basebackup_request(
-        &self,
+        &mut self,
         pgb: &mut PostgresBackend,
         tenant_id: TenantId,
         timeline_id: TimelineId,
         lsn: Option<Lsn>,
         prev_lsn: Option<Lsn>,
         full_backup: bool,
+        ctx: RequestContext,
     ) -> anyhow::Result<()> {
         // check that the timeline exists
-        let timeline = get_active_timeline_with_timeout(tenant_id, timeline_id).await?;
+        let timeline = get_active_tenant_timeline(tenant_id, timeline_id, &ctx).await?;
         let latest_gc_cutoff_lsn = timeline.get_latest_gc_cutoff_lsn();
         if let Some(lsn) = lsn {
             // Backup was requested at a particular LSN. Wait for it to arrive.
             info!("waiting for {}", lsn);
-            timeline.wait_lsn(lsn).await?;
+            timeline.wait_lsn(lsn, &ctx).await?;
             timeline
                 .check_lsn_is_in_scope(lsn, &latest_gc_cutoff_lsn)
                 .context("invalid basebackup lsn")?;
@@ -645,8 +684,15 @@ impl PageServerHandler {
         // Send a tarball of the latest layer on the timeline
         {
             let mut writer = pgb.copyout_writer();
-            basebackup::send_basebackup_tarball(&mut writer, &timeline, lsn, prev_lsn, full_backup)
-                .await?;
+            basebackup::send_basebackup_tarball(
+                &mut writer,
+                &timeline,
+                lsn,
+                prev_lsn,
+                full_backup,
+                &ctx,
+            )
+            .await?;
         }
 
         pgb.write_message(&BeMessage::CopyDone)?;
@@ -717,6 +763,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
         pgb: &mut PostgresBackend,
         query_string: &str,
     ) -> Result<(), QueryError> {
+        let ctx = self.connection_ctx.attached_child();
         debug!("process query {query_string:?}");
 
         if query_string.starts_with("pagestream ") {
@@ -734,7 +781,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
 
             self.check_permission(Some(tenant_id))?;
 
-            self.handle_pagerequests(pgb, tenant_id, timeline_id)
+            self.handle_pagerequests(pgb, tenant_id, timeline_id, ctx)
                 .await?;
         } else if query_string.starts_with("basebackup ") {
             let (_, params_raw) = query_string.split_at("basebackup ".len());
@@ -763,7 +810,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
             };
 
             // Check that the timeline exists
-            self.handle_basebackup_request(pgb, tenant_id, timeline_id, lsn, None, false)
+            self.handle_basebackup_request(pgb, tenant_id, timeline_id, lsn, None, false, ctx)
                 .await?;
             pgb.write_message(&BeMessage::CommandComplete(b"SELECT 1"))?;
         }
@@ -784,7 +831,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
                 .with_context(|| format!("Failed to parse timeline id from {}", params[1]))?;
 
             self.check_permission(Some(tenant_id))?;
-            let timeline = get_active_timeline_with_timeout(tenant_id, timeline_id).await?;
+            let timeline = get_active_tenant_timeline(tenant_id, timeline_id, &ctx).await?;
 
             let end_of_timeline = timeline.get_last_record_rlsn();
 
@@ -835,7 +882,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
             self.check_permission(Some(tenant_id))?;
 
             // Check that the timeline exists
-            self.handle_basebackup_request(pgb, tenant_id, timeline_id, lsn, prev_lsn, true)
+            self.handle_basebackup_request(pgb, tenant_id, timeline_id, lsn, prev_lsn, true, ctx)
                 .await?;
             pgb.write_message(&BeMessage::CommandComplete(b"SELECT 1"))?;
         } else if query_string.starts_with("import basebackup ") {
@@ -878,6 +925,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
                     base_lsn,
                     end_lsn,
                     pg_version,
+                    ctx,
                 )
                 .await
             {
@@ -914,7 +962,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
             self.check_permission(Some(tenant_id))?;
 
             match self
-                .handle_import_wal(pgb, tenant_id, timeline_id, start_lsn, end_lsn)
+                .handle_import_wal(pgb, tenant_id, timeline_id, start_lsn, end_lsn, ctx)
                 .await
             {
                 Ok(()) => pgb.write_message(&BeMessage::CommandComplete(b"SELECT 1"))?,
@@ -944,7 +992,7 @@ impl postgres_backend_async::Handler for PageServerHandler {
 
             self.check_permission(Some(tenant_id))?;
 
-            let tenant = get_active_tenant_with_timeout(tenant_id).await?;
+            let tenant = get_active_tenant_with_timeout(tenant_id, &ctx).await?;
             pgb.write_message(&BeMessage::RowDescription(&[
                 RowDescriptor::int8_col(b"checkpoint_distance"),
                 RowDescriptor::int8_col(b"checkpoint_timeout"),
@@ -990,27 +1038,66 @@ impl postgres_backend_async::Handler for PageServerHandler {
     }
 }
 
+#[derive(thiserror::Error, Debug)]
+enum GetActiveTenantError {
+    #[error(
+        "Timed out waiting {wait_time:?} for tenant active state. Latest state: {latest_state:?}"
+    )]
+    WaitForActiveTimeout {
+        latest_state: TenantState,
+        wait_time: Duration,
+    },
+    #[error(transparent)]
+    Other(#[from] anyhow::Error),
+}
+
+impl From<GetActiveTenantError> for QueryError {
+    fn from(e: GetActiveTenantError) -> Self {
+        match e {
+            GetActiveTenantError::WaitForActiveTimeout { .. } => QueryError::Disconnected(
+                ConnectionError::Socket(io::Error::new(io::ErrorKind::TimedOut, e.to_string())),
+            ),
+            GetActiveTenantError::Other(e) => QueryError::Other(e),
+        }
+    }
+}
+
 /// Get active tenant.
 ///
 /// If the tenant is Loading, waits for it to become Active, for up to 30 s. That
 /// ensures that queries don't fail immediately after pageserver startup, because
 /// all tenants are still loading.
-async fn get_active_tenant_with_timeout(tenant_id: TenantId) -> anyhow::Result<Arc<Tenant>> {
+async fn get_active_tenant_with_timeout(
+    tenant_id: TenantId,
+    _ctx: &RequestContext, /* require get a context to support cancellation in the future */
+) -> Result<Arc<Tenant>, GetActiveTenantError> {
     let tenant = mgr::get_tenant(tenant_id, false).await?;
-    match tokio::time::timeout(Duration::from_secs(30), tenant.wait_to_become_active()).await {
-        Ok(wait_result) => wait_result
-            // no .context(), the error message is good enough and some tests depend on it
-            .map(move |()| tenant),
-        Err(_) => anyhow::bail!("Timeout waiting for tenant {tenant_id} to become Active"),
+    let wait_time = Duration::from_secs(30);
+    match tokio::time::timeout(wait_time, tenant.wait_to_become_active()).await {
+        Ok(Ok(())) => Ok(tenant),
+        // no .context(), the error message is good enough and some tests depend on it
+        Ok(Err(wait_error)) => Err(GetActiveTenantError::Other(wait_error)),
+        Err(_) => {
+            let latest_state = tenant.current_state();
+            if latest_state == TenantState::Active {
+                Ok(tenant)
+            } else {
+                Err(GetActiveTenantError::WaitForActiveTimeout {
+                    latest_state,
+                    wait_time,
+                })
+            }
+        }
     }
 }
 
 /// Shorthand for getting a reference to a Timeline of an Active tenant.
-async fn get_active_timeline_with_timeout(
+async fn get_active_tenant_timeline(
     tenant_id: TenantId,
     timeline_id: TimelineId,
-) -> anyhow::Result<Arc<Timeline>> {
-    get_active_tenant_with_timeout(tenant_id)
-        .await
-        .and_then(|tenant| tenant.get_timeline(timeline_id, true))
+    ctx: &RequestContext,
+) -> Result<Arc<Timeline>, GetActiveTenantError> {
+    let tenant = get_active_tenant_with_timeout(tenant_id, ctx).await?;
+    let timeline = tenant.get_timeline(timeline_id, true)?;
+    Ok(timeline)
 }

pageserver/src/pgdatadir_mapping.rs

@@ -7,6 +7,7 @@
 //! Clarify that)
 //!
 use super::tenant::{PageReconstructError, Timeline};
+use crate::context::RequestContext;
 use crate::keyspace::{KeySpace, KeySpaceAccum};
 use crate::repository::*;
 use crate::walrecord::NeonWalRecord;
@@ -97,6 +98,7 @@ impl Timeline {
         blknum: BlockNumber,
         lsn: Lsn,
         latest: bool,
+        ctx: &RequestContext,
     ) -> Result<Bytes, PageReconstructError> {
         if tag.relnode == 0 {
             return Err(PageReconstructError::Other(anyhow::anyhow!(
@@ -104,7 +106,7 @@ impl Timeline {
             )));
         }
 
-        let nblocks = self.get_rel_size(tag, lsn, latest).await?;
+        let nblocks = self.get_rel_size(tag, lsn, latest, ctx).await?;
         if blknum >= nblocks {
             debug!(
                 "read beyond EOF at {} blk {} at {}, size is {}: returning all-zeros page",
@@ -114,7 +116,7 @@ impl Timeline {
         }
 
         let key = rel_block_to_key(tag, blknum);
-        self.get(key, lsn).await
+        self.get(key, lsn, ctx).await
     }
 
     // Get size of a database in blocks
@@ -124,13 +126,14 @@ impl Timeline {
         dbnode: Oid,
         lsn: Lsn,
         latest: bool,
+        ctx: &RequestContext,
     ) -> Result<usize, PageReconstructError> {
         let mut total_blocks = 0;
 
-        let rels = self.list_rels(spcnode, dbnode, lsn).await?;
+        let rels = self.list_rels(spcnode, dbnode, lsn, ctx).await?;
 
         for rel in rels {
-            let n_blocks = self.get_rel_size(rel, lsn, latest).await?;
+            let n_blocks = self.get_rel_size(rel, lsn, latest, ctx).await?;
             total_blocks += n_blocks as usize;
         }
         Ok(total_blocks)
@@ -142,6 +145,7 @@ impl Timeline {
         tag: RelTag,
         lsn: Lsn,
         latest: bool,
+        ctx: &RequestContext,
     ) -> Result<BlockNumber, PageReconstructError> {
         if tag.relnode == 0 {
             return Err(PageReconstructError::Other(anyhow::anyhow!(
@@ -154,7 +158,7 @@ impl Timeline {
         }
 
         if (tag.forknum == FSM_FORKNUM || tag.forknum == VISIBILITYMAP_FORKNUM)
-            && !self.get_rel_exists(tag, lsn, latest).await?
+            && !self.get_rel_exists(tag, lsn, latest, ctx).await?
         {
             // FIXME: Postgres sometimes calls smgrcreate() to create
             // FSM, and smgrnblocks() on it immediately afterwards,
@@ -164,7 +168,7 @@ impl Timeline {
         }
 
         let key = rel_size_to_key(tag);
-        let mut buf = self.get(key, lsn).await?;
+        let mut buf = self.get(key, lsn, ctx).await?;
         let nblocks = buf.get_u32_le();
 
         if latest {
@@ -186,6 +190,7 @@ impl Timeline {
         tag: RelTag,
         lsn: Lsn,
         _latest: bool,
+        ctx: &RequestContext,
     ) -> Result<bool, PageReconstructError> {
         if tag.relnode == 0 {
             return Err(PageReconstructError::Other(anyhow::anyhow!(
@@ -199,7 +204,7 @@ impl Timeline {
         }
         // fetch directory listing
         let key = rel_dir_to_key(tag.spcnode, tag.dbnode);
-        let buf = self.get(key, lsn).await?;
+        let buf = self.get(key, lsn, ctx).await?;
 
         match RelDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => {
@@ -216,10 +221,11 @@ impl Timeline {
         spcnode: Oid,
         dbnode: Oid,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<HashSet<RelTag>, PageReconstructError> {
         // fetch directory listing
         let key = rel_dir_to_key(spcnode, dbnode);
-        let buf = self.get(key, lsn).await?;
+        let buf = self.get(key, lsn, ctx).await?;
 
         match RelDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => {
@@ -244,9 +250,10 @@ impl Timeline {
         segno: u32,
         blknum: BlockNumber,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<Bytes, PageReconstructError> {
         let key = slru_block_to_key(kind, segno, blknum);
-        self.get(key, lsn).await
+        self.get(key, lsn, ctx).await
     }
 
     /// Get size of an SLRU segment
@@ -255,9 +262,10 @@ impl Timeline {
         kind: SlruKind,
         segno: u32,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<BlockNumber, PageReconstructError> {
         let key = slru_segment_size_to_key(kind, segno);
-        let mut buf = self.get(key, lsn).await?;
+        let mut buf = self.get(key, lsn, ctx).await?;
         Ok(buf.get_u32_le())
     }
 
@@ -267,10 +275,11 @@ impl Timeline {
         kind: SlruKind,
         segno: u32,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<bool, PageReconstructError> {
         // fetch directory listing
         let key = slru_dir_to_key(kind);
-        let buf = self.get(key, lsn).await?;
+        let buf = self.get(key, lsn, ctx).await?;
 
         match SlruSegmentDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => {
@@ -291,6 +300,7 @@ impl Timeline {
     pub async fn find_lsn_for_timestamp(
         &self,
         search_timestamp: TimestampTz,
+        ctx: &RequestContext,
     ) -> Result<LsnForTimestamp, PageReconstructError> {
         let gc_cutoff_lsn_guard = self.get_latest_gc_cutoff_lsn();
         let min_lsn = *gc_cutoff_lsn_guard;
@@ -313,6 +323,7 @@ impl Timeline {
                     Lsn(mid * 8),
                     &mut found_smaller,
                     &mut found_larger,
+                    ctx,
                 )
                 .await?;
 
@@ -362,14 +373,18 @@ impl Timeline {
         probe_lsn: Lsn,
         found_smaller: &mut bool,
         found_larger: &mut bool,
+        ctx: &RequestContext,
     ) -> Result<bool, PageReconstructError> {
-        for segno in self.list_slru_segments(SlruKind::Clog, probe_lsn).await? {
+        for segno in self
+            .list_slru_segments(SlruKind::Clog, probe_lsn, ctx)
+            .await?
+        {
             let nblocks = self
-                .get_slru_segment_size(SlruKind::Clog, segno, probe_lsn)
+                .get_slru_segment_size(SlruKind::Clog, segno, probe_lsn, ctx)
                 .await?;
             for blknum in (0..nblocks).rev() {
                 let clog_page = self
-                    .get_slru_page_at_lsn(SlruKind::Clog, segno, blknum, probe_lsn)
+                    .get_slru_page_at_lsn(SlruKind::Clog, segno, blknum, probe_lsn, ctx)
                     .await?;
 
                 if clog_page.len() == BLCKSZ as usize + 8 {
@@ -394,11 +409,12 @@ impl Timeline {
         &self,
         kind: SlruKind,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<HashSet<u32>, PageReconstructError> {
         // fetch directory entry
         let key = slru_dir_to_key(kind);
 
-        let buf = self.get(key, lsn).await?;
+        let buf = self.get(key, lsn, ctx).await?;
         match SlruSegmentDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => Ok(dir.segments),
             Err(e) => Err(PageReconstructError::from(e)),
@@ -410,18 +426,21 @@ impl Timeline {
         spcnode: Oid,
         dbnode: Oid,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<Bytes, PageReconstructError> {
         let key = relmap_file_key(spcnode, dbnode);
 
-        self.get(key, lsn).await
+        let buf = self.get(key, lsn, ctx).await?;
+        Ok(buf)
     }
 
     pub async fn list_dbdirs(
         &self,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<HashMap<(Oid, Oid), bool>, PageReconstructError> {
         // fetch directory entry
-        let buf = self.get(DBDIR_KEY, lsn).await?;
+        let buf = self.get(DBDIR_KEY, lsn, ctx).await?;
 
         match DbDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => Ok(dir.dbdirs),
@@ -433,18 +452,20 @@ impl Timeline {
         &self,
         xid: TransactionId,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<Bytes, PageReconstructError> {
         let key = twophase_file_key(xid);
-        let buf = self.get(key, lsn).await?;
+        let buf = self.get(key, lsn, ctx).await?;
         Ok(buf)
     }
 
     pub async fn list_twophase_files(
         &self,
         lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<HashSet<TransactionId>, PageReconstructError> {
         // fetch directory entry
-        let buf = self.get(TWOPHASEDIR_KEY, lsn).await?;
+        let buf = self.get(TWOPHASEDIR_KEY, lsn, ctx).await?;
 
         match TwoPhaseDirectory::des(&buf).context("deserialization failure") {
             Ok(dir) => Ok(dir.xids),
@@ -452,12 +473,20 @@ impl Timeline {
         }
     }
 
-    pub async fn get_control_file(&self, lsn: Lsn) -> Result<Bytes, PageReconstructError> {
-        self.get(CONTROLFILE_KEY, lsn).await
+    pub async fn get_control_file(
+        &self,
+        lsn: Lsn,
+        ctx: &RequestContext,
+    ) -> Result<Bytes, PageReconstructError> {
+        self.get(CONTROLFILE_KEY, lsn, ctx).await
     }
 
-    pub async fn get_checkpoint(&self, lsn: Lsn) -> Result<Bytes, PageReconstructError> {
-        self.get(CHECKPOINT_KEY, lsn).await
+    pub async fn get_checkpoint(
+        &self,
+        lsn: Lsn,
+        ctx: &RequestContext,
+    ) -> Result<Bytes, PageReconstructError> {
+        self.get(CHECKPOINT_KEY, lsn, ctx).await
     }
 
     /// Does the same as get_current_logical_size but counted on demand.
@@ -469,15 +498,16 @@ impl Timeline {
         &self,
         lsn: Lsn,
         cancel: CancellationToken,
+        ctx: &RequestContext,
     ) -> Result<u64, CalculateLogicalSizeError> {
         // Fetch list of database dirs and iterate them
-        let buf = self.get(DBDIR_KEY, lsn).await.context("read dbdir")?;
+        let buf = self.get(DBDIR_KEY, lsn, ctx).await.context("read dbdir")?;
         let dbdir = DbDirectory::des(&buf).context("deserialize db directory")?;
 
         let mut total_size: u64 = 0;
         for (spcnode, dbnode) in dbdir.dbdirs.keys() {
             for rel in self
-                .list_rels(*spcnode, *dbnode, lsn)
+                .list_rels(*spcnode, *dbnode, lsn, ctx)
                 .await
                 .context("list rels")?
             {
@@ -486,9 +516,9 @@ impl Timeline {
                 }
                 let relsize_key = rel_size_to_key(rel);
                 let mut buf = self
-                    .get(relsize_key, lsn)
+                    .get(relsize_key, lsn, ctx)
                     .await
-                    .context("read relation size of {rel:?}")?;
+                    .with_context(|| format!("read relation size of {rel:?}"))?;
                 let relsize = buf.get_u32_le();
 
                 total_size += relsize as u64;
@@ -501,7 +531,11 @@ impl Timeline {
     /// Get a KeySpace that covers all the Keys that are in use at the given LSN.
     /// Anything that's not listed maybe removed from the underlying storage (from
     /// that LSN forwards).
-    pub async fn collect_keyspace(&self, lsn: Lsn) -> anyhow::Result<KeySpace> {
+    pub async fn collect_keyspace(
+        &self,
+        lsn: Lsn,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<KeySpace> {
         // Iterate through key ranges, greedily packing them into partitions
         let mut result = KeySpaceAccum::new();
 
@@ -509,7 +543,7 @@ impl Timeline {
         result.add_key(DBDIR_KEY);
 
         // Fetch list of database dirs and iterate them
-        let buf = self.get(DBDIR_KEY, lsn).await?;
+        let buf = self.get(DBDIR_KEY, lsn, ctx).await?;
         let dbdir = DbDirectory::des(&buf).context("deserialization failure")?;
 
         let mut dbs: Vec<(Oid, Oid)> = dbdir.dbdirs.keys().cloned().collect();
@@ -519,14 +553,14 @@ impl Timeline {
             result.add_key(rel_dir_to_key(spcnode, dbnode));
 
             let mut rels: Vec<RelTag> = self
-                .list_rels(spcnode, dbnode, lsn)
+                .list_rels(spcnode, dbnode, lsn, ctx)
                 .await?
                 .into_iter()
                 .collect();
             rels.sort_unstable();
             for rel in rels {
                 let relsize_key = rel_size_to_key(rel);
-                let mut buf = self.get(relsize_key, lsn).await?;
+                let mut buf = self.get(relsize_key, lsn, ctx).await?;
                 let relsize = buf.get_u32_le();
 
                 result.add_range(rel_block_to_key(rel, 0)..rel_block_to_key(rel, relsize));
@@ -542,13 +576,13 @@ impl Timeline {
         ] {
             let slrudir_key = slru_dir_to_key(kind);
             result.add_key(slrudir_key);
-            let buf = self.get(slrudir_key, lsn).await?;
+            let buf = self.get(slrudir_key, lsn, ctx).await?;
             let dir = SlruSegmentDirectory::des(&buf).context("deserialization failure")?;
             let mut segments: Vec<u32> = dir.segments.iter().cloned().collect();
             segments.sort_unstable();
             for segno in segments {
                 let segsize_key = slru_segment_size_to_key(kind, segno);
-                let mut buf = self.get(segsize_key, lsn).await?;
+                let mut buf = self.get(segsize_key, lsn, ctx).await?;
                 let segsize = buf.get_u32_le();
 
                 result.add_range(
@@ -560,7 +594,7 @@ impl Timeline {
 
         // Then pg_twophase
         result.add_key(TWOPHASEDIR_KEY);
-        let buf = self.get(TWOPHASEDIR_KEY, lsn).await?;
+        let buf = self.get(TWOPHASEDIR_KEY, lsn, ctx).await?;
         let twophase_dir = TwoPhaseDirectory::des(&buf).context("deserialization failure")?;
         let mut xids: Vec<TransactionId> = twophase_dir.xids.iter().cloned().collect();
         xids.sort_unstable();
@@ -723,9 +757,10 @@ impl<'a> DatadirModification<'a> {
         spcnode: Oid,
         dbnode: Oid,
         img: Bytes,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         // Add it to the directory (if it doesn't exist already)
-        let buf = self.get(DBDIR_KEY).await?;
+        let buf = self.get(DBDIR_KEY, ctx).await?;
         let mut dbdir = DbDirectory::des(&buf)?;
 
         let r = dbdir.dbdirs.insert((spcnode, dbnode), true);
@@ -755,9 +790,10 @@ impl<'a> DatadirModification<'a> {
         &mut self,
         xid: TransactionId,
         img: Bytes,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         // Add it to the directory entry
-        let buf = self.get(TWOPHASEDIR_KEY).await?;
+        let buf = self.get(TWOPHASEDIR_KEY, ctx).await?;
         let mut dir = TwoPhaseDirectory::des(&buf)?;
         if !dir.xids.insert(xid) {
             anyhow::bail!("twophase file for xid {} already exists", xid);
@@ -781,16 +817,21 @@ impl<'a> DatadirModification<'a> {
         Ok(())
     }
 
-    pub async fn drop_dbdir(&mut self, spcnode: Oid, dbnode: Oid) -> anyhow::Result<()> {
+    pub async fn drop_dbdir(
+        &mut self,
+        spcnode: Oid,
+        dbnode: Oid,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<()> {
         let req_lsn = self.tline.get_last_record_lsn();
 
         let total_blocks = self
             .tline
-            .get_db_size(spcnode, dbnode, req_lsn, true)
+            .get_db_size(spcnode, dbnode, req_lsn, true, ctx)
             .await?;
 
         // Remove entry from dbdir
-        let buf = self.get(DBDIR_KEY).await?;
+        let buf = self.get(DBDIR_KEY, ctx).await?;
         let mut dir = DbDirectory::des(&buf)?;
         if dir.dbdirs.remove(&(spcnode, dbnode)).is_some() {
             let buf = DbDirectory::ser(&dir)?;
@@ -817,11 +858,12 @@ impl<'a> DatadirModification<'a> {
         &mut self,
         rel: RelTag,
         nblocks: BlockNumber,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         anyhow::ensure!(rel.relnode != 0, "invalid relnode");
         // It's possible that this is the first rel for this db in this
         // tablespace.  Create the reldir entry for it if so.
-        let mut dbdir = DbDirectory::des(&self.get(DBDIR_KEY).await?)?;
+        let mut dbdir = DbDirectory::des(&self.get(DBDIR_KEY, ctx).await?)?;
         let rel_dir_key = rel_dir_to_key(rel.spcnode, rel.dbnode);
         let mut rel_dir = if dbdir.dbdirs.get(&(rel.spcnode, rel.dbnode)).is_none() {
             // Didn't exist. Update dbdir
@@ -833,7 +875,7 @@ impl<'a> DatadirModification<'a> {
             RelDirectory::default()
         } else {
             // reldir already exists, fetch it
-            RelDirectory::des(&self.get(rel_dir_key).await?)?
+            RelDirectory::des(&self.get(rel_dir_key, ctx).await?)?
         };
 
         // Add the new relation to the rel directory entry, and write it back
@@ -865,13 +907,14 @@ impl<'a> DatadirModification<'a> {
         &mut self,
         rel: RelTag,
         nblocks: BlockNumber,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         anyhow::ensure!(rel.relnode != 0, "invalid relnode");
         let last_lsn = self.tline.get_last_record_lsn();
-        if self.tline.get_rel_exists(rel, last_lsn, true).await? {
+        if self.tline.get_rel_exists(rel, last_lsn, true, ctx).await? {
             let size_key = rel_size_to_key(rel);
             // Fetch the old size first
-            let old_size = self.get(size_key).await?.get_u32_le();
+            let old_size = self.get(size_key, ctx).await?.get_u32_le();
 
             // Update the entry with the new size.
             let buf = nblocks.to_le_bytes();
@@ -895,12 +938,13 @@ impl<'a> DatadirModification<'a> {
         &mut self,
         rel: RelTag,
         nblocks: BlockNumber,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         anyhow::ensure!(rel.relnode != 0, "invalid relnode");
 
         // Put size
         let size_key = rel_size_to_key(rel);
-        let old_size = self.get(size_key).await?.get_u32_le();
+        let old_size = self.get(size_key, ctx).await?.get_u32_le();
 
         // only extend relation here. never decrease the size
         if nblocks > old_size {
@@ -916,12 +960,12 @@ impl<'a> DatadirModification<'a> {
     }
 
     /// Drop a relation.
-    pub async fn put_rel_drop(&mut self, rel: RelTag) -> anyhow::Result<()> {
+    pub async fn put_rel_drop(&mut self, rel: RelTag, ctx: &RequestContext) -> anyhow::Result<()> {
         anyhow::ensure!(rel.relnode != 0, "invalid relnode");
 
         // Remove it from the directory entry
         let dir_key = rel_dir_to_key(rel.spcnode, rel.dbnode);
-        let buf = self.get(dir_key).await?;
+        let buf = self.get(dir_key, ctx).await?;
         let mut dir = RelDirectory::des(&buf)?;
 
         if dir.rels.remove(&(rel.relnode, rel.forknum)) {
@@ -932,7 +976,7 @@ impl<'a> DatadirModification<'a> {
 
         // update logical size
         let size_key = rel_size_to_key(rel);
-        let old_size = self.get(size_key).await?.get_u32_le();
+        let old_size = self.get(size_key, ctx).await?.get_u32_le();
         self.pending_nblocks -= old_size as i64;
 
         // Remove enty from relation size cache
@@ -949,10 +993,11 @@ impl<'a> DatadirModification<'a> {
         kind: SlruKind,
         segno: u32,
         nblocks: BlockNumber,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         // Add it to the directory entry
         let dir_key = slru_dir_to_key(kind);
-        let buf = self.get(dir_key).await?;
+        let buf = self.get(dir_key, ctx).await?;
         let mut dir = SlruSegmentDirectory::des(&buf)?;
 
         if !dir.segments.insert(segno) {
@@ -988,10 +1033,15 @@ impl<'a> DatadirModification<'a> {
     }
 
     /// This method is used for marking truncated SLRU files
-    pub async fn drop_slru_segment(&mut self, kind: SlruKind, segno: u32) -> anyhow::Result<()> {
+    pub async fn drop_slru_segment(
+        &mut self,
+        kind: SlruKind,
+        segno: u32,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<()> {
         // Remove it from the directory entry
         let dir_key = slru_dir_to_key(kind);
-        let buf = self.get(dir_key).await?;
+        let buf = self.get(dir_key, ctx).await?;
         let mut dir = SlruSegmentDirectory::des(&buf)?;
 
         if !dir.segments.remove(&segno) {
@@ -1015,9 +1065,13 @@ impl<'a> DatadirModification<'a> {
     }
 
     /// This method is used for marking truncated SLRU files
-    pub async fn drop_twophase_file(&mut self, xid: TransactionId) -> anyhow::Result<()> {
+    pub async fn drop_twophase_file(
+        &mut self,
+        xid: TransactionId,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<()> {
         // Remove it from the directory entry
-        let buf = self.get(TWOPHASEDIR_KEY).await?;
+        let buf = self.get(TWOPHASEDIR_KEY, ctx).await?;
         let mut dir = TwoPhaseDirectory::des(&buf)?;
 
         if !dir.xids.remove(&xid) {
@@ -1111,7 +1165,7 @@ impl<'a> DatadirModification<'a> {
 
     // Internal helper functions to batch the modifications
 
-    async fn get(&self, key: Key) -> Result<Bytes, PageReconstructError> {
+    async fn get(&self, key: Key, ctx: &RequestContext) -> Result<Bytes, PageReconstructError> {
         // Have we already updated the same key? Read the pending updated
         // version in that case.
         //
@@ -1132,7 +1186,7 @@ impl<'a> DatadirModification<'a> {
             }
         } else {
             let lsn = Lsn::max(self.tline.get_last_record_lsn(), self.lsn);
-            self.tline.get(key, lsn).await
+            self.tline.get(key, lsn, ctx).await
         }
     }
 
@@ -1405,15 +1459,15 @@ fn slru_segment_key_range(kind: SlruKind, segno: u32) -> Range<Key> {
     Key {
         field1: 0x01,
         field2,
-        field3: segno,
-        field4: 0,
+        field3: 1,
+        field4: segno,
         field5: 0,
         field6: 0,
     }..Key {
         field1: 0x01,
         field2,
-        field3: segno,
-        field4: 0,
+        field3: 1,
+        field4: segno,
         field5: 1,
         field6: 0,
     }
@@ -1542,10 +1596,11 @@ pub fn create_test_timeline(
     tenant: &crate::tenant::Tenant,
     timeline_id: utils::id::TimelineId,
     pg_version: u32,
+    ctx: &RequestContext,
 ) -> anyhow::Result<std::sync::Arc<Timeline>> {
     let tline = tenant
-        .create_empty_timeline(timeline_id, Lsn(8), pg_version)?
-        .initialize()?;
+        .create_empty_timeline(timeline_id, Lsn(8), pg_version, ctx)?
+        .initialize(ctx)?;
     let mut m = tline.begin_modification(Lsn(8));
     m.init_empty()?;
     m.commit()?;

pageserver/src/repository.rs

@@ -37,6 +37,17 @@ impl Key {
             | self.field6 as i128
     }
 
+    pub fn from_i128(x: i128) -> Self {
+        Key {
+            field1: ((x >> 120) & 0xf) as u8,
+            field2: ((x >> 104) & 0xFFFF) as u32,
+            field3: (x >> 72) as u32,
+            field4: (x >> 40) as u32,
+            field5: (x >> 32) as u8,
+            field6: x as u32,
+        }
+    }
+
     pub fn next(&self) -> Key {
         self.add(1)
     }

pageserver/src/task_mgr.rs

@@ -171,6 +171,9 @@ task_local! {
 ///
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
 pub enum TaskKind {
+    // Pageserver startup, i.e., `main`
+    Startup,
+
     // libpq listener task. It just accepts connection and spawns a
     // PageRequestHandler task for each connection.
     LibpqEndpointListener,
@@ -183,13 +186,37 @@ pub enum TaskKind {
     // associated with one later, after receiving a command from the client.
     PageRequestHandler,
 
-    // Manages the WAL receiver connection for one timeline. It subscribes to
-    // events from storage_broker, decides which safekeeper to connect to. It spawns a
-    // separate WalReceiverConnection task to handle each connection.
+    /// Manages the WAL receiver connection for one timeline.
+    /// It subscribes to events from storage_broker and decides which safekeeper to connect to.
+    /// Once the decision has been made, it establishes the connection using the `tokio-postgres` library.
+    /// There is at most one connection at any given time.
+    ///
+    /// That `tokio-postgres` library represents a connection as two objects: a `Client` and a `Connection`.
+    /// The `Client` object is what library users use to make requests & get responses.
+    /// Internally, `Client` hands over requests to the `Connection` object.
+    /// The `Connection` object is responsible for speaking the wire protocol.
+    ///
+    /// Walreceiver uses its own abstraction called `TaskHandle` to represent the activity of establishing and handling a connection.
+    /// That abstraction doesn't use `task_mgr`.
+    /// The [`WalReceiverManager`] task ensures that this `TaskHandle` task does not outlive the [`WalReceiverManager`] task.
+    /// For the `RequestContext` that we hand to the TaskHandle, we use the [`WalReceiverConnectionHandler`] task kind.
+    ///
+    /// Once the connection is established, the `TaskHandle` task creates a
+    /// [`WalReceiverConnectionPoller`] task_mgr task that is responsible for polling
+    /// the `Connection` object.
+    /// A `CancellationToken` created by the `TaskHandle` task ensures
+    /// that the [`WalReceiverConnectionPoller`] task will cancel soon after as the `TaskHandle` is dropped.
     WalReceiverManager,
 
-    // Handles a connection to a safekeeper, to stream WAL to a timeline.
-    WalReceiverConnection,
+    /// The `TaskHandle` task that executes [`walreceiver_connection::handle_walreceiver_connection`].
+    /// Not a `task_mgr` task, but we use this `TaskKind` for its `RequestContext`.
+    /// See the comment on [`WalReceiverManager`].
+    WalReceiverConnectionHandler,
+
+    /// The task that polls the `tokio-postgres::Connection` object.
+    /// Spawned by task [`WalReceiverConnectionHandler`].
+    /// See the comment on [`WalReceiverManager`].
+    WalReceiverConnectionPoller,
 
     // Garbage collection worker. One per tenant
     GarbageCollector,
@@ -200,6 +227,8 @@ pub enum TaskKind {
     // Initial logical size calculation
     InitialLogicalSizeCalculation,
 
+    OndemandLogicalSizeCalculation,
+
     // Task that flushes frozen in-memory layers to disk
     LayerFlushTask,
 
@@ -220,6 +249,14 @@ pub enum TaskKind {
 
     // task that drives downloading layers
     DownloadAllRemoteLayers,
+    // Task that calculates synthetis size for all active tenants
+    CalculateSyntheticSize,
+
+    // A request that comes in via the pageserver HTTP API.
+    MgmtRequest,
+
+    #[cfg(test)]
+    UnitTest,
 }
 
 #[derive(Default)]

pageserver/src/tenant/config.rs

@@ -28,7 +28,12 @@ pub mod defaults {
     pub const DEFAULT_COMPACTION_THRESHOLD: usize = 10;
 
     pub const DEFAULT_GC_HORIZON: u64 = 64 * 1024 * 1024;
-    pub const DEFAULT_GC_PERIOD: &str = "100 s";
+
+    // Large DEFAULT_GC_PERIOD is fine as long as PITR_INTERVAL is larger.
+    // If there's a need to decrease this value, first make sure that GC
+    // doesn't hold a layer map write lock for non-trivial operations.
+    // Relevant: https://github.com/neondatabase/neon/issues/3394
+    pub const DEFAULT_GC_PERIOD: &str = "1 hr";
     pub const DEFAULT_IMAGE_CREATION_THRESHOLD: usize = 3;
     pub const DEFAULT_PITR_INTERVAL: &str = "7 days";
     pub const DEFAULT_WALRECEIVER_CONNECT_TIMEOUT: &str = "2 seconds";

pageserver/src/tenant/layer_map/historic_layer_coverage.rs

@@ -0,0 +1,583 @@
+use std::collections::BTreeMap;
+use std::ops::Range;
+
+use tracing::info;
+
+use super::layer_coverage::LayerCoverageTuple;
+
+/// Layers in this module are identified and indexed by this data.
+///
+/// This is a helper struct to enable sorting layers by lsn.start.
+///
+/// These three values are enough to uniquely identify a layer, since
+/// a layer is obligated to contain all contents within range, so two
+/// deltas (or images) with the same range have identical content.
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub struct LayerKey {
+    // TODO I use i128 and u64 because it was easy for prototyping,
+    //      testing, and benchmarking. If we can use the Lsn and Key
+    //      types without overhead that would be preferable.
+    pub key: Range<i128>,
+    pub lsn: Range<u64>,
+    pub is_image: bool,
+}
+
+impl PartialOrd for LayerKey {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+impl Ord for LayerKey {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        // NOTE we really care about comparing by lsn.start first
+        self.lsn
+            .start
+            .cmp(&other.lsn.start)
+            .then(self.lsn.end.cmp(&other.lsn.end))
+            .then(self.key.start.cmp(&other.key.start))
+            .then(self.key.end.cmp(&other.key.end))
+            .then(self.is_image.cmp(&other.is_image))
+    }
+}
+
+/// Efficiently queryable layer coverage for each LSN.
+///
+/// Allows answering layer map queries very efficiently,
+/// but doesn't allow retroactive insertion, which is
+/// sometimes necessary. See BufferedHistoricLayerCoverage.
+pub struct HistoricLayerCoverage<Value> {
+    /// The latest state
+    head: LayerCoverageTuple<Value>,
+
+    /// All previous states
+    historic: BTreeMap<u64, LayerCoverageTuple<Value>>,
+}
+
+impl<T: Clone> Default for HistoricLayerCoverage<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<Value: Clone> HistoricLayerCoverage<Value> {
+    pub fn new() -> Self {
+        Self {
+            head: LayerCoverageTuple::default(),
+            historic: BTreeMap::default(),
+        }
+    }
+
+    /// Add a layer
+    ///
+    /// Panics if new layer has older lsn.start than an existing layer.
+    /// See BufferedHistoricLayerCoverage for a more general insertion method.
+    pub fn insert(&mut self, layer_key: LayerKey, value: Value) {
+        // It's only a persistent map, not a retroactive one
+        if let Some(last_entry) = self.historic.iter().next_back() {
+            let last_lsn = last_entry.0;
+            if layer_key.lsn.start < *last_lsn {
+                panic!("unexpected retroactive insert");
+            }
+        }
+
+        // Insert into data structure
+        if layer_key.is_image {
+            self.head
+                .image_coverage
+                .insert(layer_key.key, layer_key.lsn.clone(), value);
+        } else {
+            self.head
+                .delta_coverage
+                .insert(layer_key.key, layer_key.lsn.clone(), value);
+        }
+
+        // Remember history. Clone is O(1)
+        self.historic.insert(layer_key.lsn.start, self.head.clone());
+    }
+
+    /// Query at a particular LSN, inclusive
+    pub fn get_version(&self, lsn: u64) -> Option<&LayerCoverageTuple<Value>> {
+        match self.historic.range(..=lsn).next_back() {
+            Some((_, v)) => Some(v),
+            None => None,
+        }
+    }
+
+    /// Remove all entries after a certain LSN (inclusive)
+    pub fn trim(&mut self, begin: &u64) {
+        self.historic.split_off(begin);
+        self.head = self
+            .historic
+            .iter()
+            .rev()
+            .next()
+            .map(|(_, v)| v.clone())
+            .unwrap_or_default();
+    }
+}
+
+/// This is the most basic test that demonstrates intended usage.
+/// All layers in this test have height 1.
+#[test]
+fn test_persistent_simple() {
+    let mut map = HistoricLayerCoverage::<String>::new();
+    map.insert(
+        LayerKey {
+            key: 0..5,
+            lsn: 100..101,
+            is_image: true,
+        },
+        "Layer 1".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 3..9,
+            lsn: 110..111,
+            is_image: true,
+        },
+        "Layer 2".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 5..6,
+            lsn: 120..121,
+            is_image: true,
+        },
+        "Layer 3".to_string(),
+    );
+
+    // After Layer 1 insertion
+    let version = map.get_version(105).unwrap();
+    assert_eq!(version.image_coverage.query(1), Some("Layer 1".to_string()));
+    assert_eq!(version.image_coverage.query(4), Some("Layer 1".to_string()));
+
+    // After Layer 2 insertion
+    let version = map.get_version(115).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Layer 2".to_string()));
+    assert_eq!(version.image_coverage.query(8), Some("Layer 2".to_string()));
+    assert_eq!(version.image_coverage.query(11), None);
+
+    // After Layer 3 insertion
+    let version = map.get_version(125).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Layer 2".to_string()));
+    assert_eq!(version.image_coverage.query(5), Some("Layer 3".to_string()));
+    assert_eq!(version.image_coverage.query(7), Some("Layer 2".to_string()));
+}
+
+/// Cover simple off-by-one edge cases
+#[test]
+fn test_off_by_one() {
+    let mut map = HistoricLayerCoverage::<String>::new();
+    map.insert(
+        LayerKey {
+            key: 3..5,
+            lsn: 100..110,
+            is_image: true,
+        },
+        "Layer 1".to_string(),
+    );
+
+    // Check different LSNs
+    let version = map.get_version(99);
+    assert!(version.is_none());
+    let version = map.get_version(100).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Layer 1".to_string()));
+    let version = map.get_version(110).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Layer 1".to_string()));
+
+    // Check different keys
+    let version = map.get_version(105).unwrap();
+    assert_eq!(version.image_coverage.query(2), None);
+    assert_eq!(version.image_coverage.query(3), Some("Layer 1".to_string()));
+    assert_eq!(version.image_coverage.query(4), Some("Layer 1".to_string()));
+    assert_eq!(version.image_coverage.query(5), None);
+}
+
+/// Cover edge cases where layers begin or end on the same key
+#[test]
+fn test_key_collision() {
+    let mut map = HistoricLayerCoverage::<String>::new();
+
+    map.insert(
+        LayerKey {
+            key: 3..5,
+            lsn: 100..110,
+            is_image: true,
+        },
+        "Layer 10".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 5..8,
+            lsn: 100..110,
+            is_image: true,
+        },
+        "Layer 11".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 3..4,
+            lsn: 200..210,
+            is_image: true,
+        },
+        "Layer 20".to_string(),
+    );
+
+    // Check after layer 11
+    let version = map.get_version(105).unwrap();
+    assert_eq!(version.image_coverage.query(2), None);
+    assert_eq!(
+        version.image_coverage.query(3),
+        Some("Layer 10".to_string())
+    );
+    assert_eq!(
+        version.image_coverage.query(5),
+        Some("Layer 11".to_string())
+    );
+    assert_eq!(
+        version.image_coverage.query(7),
+        Some("Layer 11".to_string())
+    );
+    assert_eq!(version.image_coverage.query(8), None);
+
+    // Check after layer 20
+    let version = map.get_version(205).unwrap();
+    assert_eq!(version.image_coverage.query(2), None);
+    assert_eq!(
+        version.image_coverage.query(3),
+        Some("Layer 20".to_string())
+    );
+    assert_eq!(
+        version.image_coverage.query(5),
+        Some("Layer 11".to_string())
+    );
+    assert_eq!(
+        version.image_coverage.query(7),
+        Some("Layer 11".to_string())
+    );
+    assert_eq!(version.image_coverage.query(8), None);
+}
+
+/// Test when rectangles have nontrivial height and possibly overlap
+#[test]
+fn test_persistent_overlapping() {
+    let mut map = HistoricLayerCoverage::<String>::new();
+
+    // Add 3 key-disjoint layers with varying LSN ranges
+    map.insert(
+        LayerKey {
+            key: 1..2,
+            lsn: 100..200,
+            is_image: true,
+        },
+        "Layer 1".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 4..5,
+            lsn: 110..200,
+            is_image: true,
+        },
+        "Layer 2".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 7..8,
+            lsn: 120..300,
+            is_image: true,
+        },
+        "Layer 3".to_string(),
+    );
+
+    // Add wide and short layer
+    map.insert(
+        LayerKey {
+            key: 0..9,
+            lsn: 130..199,
+            is_image: true,
+        },
+        "Layer 4".to_string(),
+    );
+
+    // Add wide layer taller than some
+    map.insert(
+        LayerKey {
+            key: 0..9,
+            lsn: 140..201,
+            is_image: true,
+        },
+        "Layer 5".to_string(),
+    );
+
+    // Add wide layer taller than all
+    map.insert(
+        LayerKey {
+            key: 0..9,
+            lsn: 150..301,
+            is_image: true,
+        },
+        "Layer 6".to_string(),
+    );
+
+    // After layer 4 insertion
+    let version = map.get_version(135).unwrap();
+    assert_eq!(version.image_coverage.query(0), Some("Layer 4".to_string()));
+    assert_eq!(version.image_coverage.query(1), Some("Layer 1".to_string()));
+    assert_eq!(version.image_coverage.query(2), Some("Layer 4".to_string()));
+    assert_eq!(version.image_coverage.query(4), Some("Layer 2".to_string()));
+    assert_eq!(version.image_coverage.query(5), Some("Layer 4".to_string()));
+    assert_eq!(version.image_coverage.query(7), Some("Layer 3".to_string()));
+    assert_eq!(version.image_coverage.query(8), Some("Layer 4".to_string()));
+
+    // After layer 5 insertion
+    let version = map.get_version(145).unwrap();
+    assert_eq!(version.image_coverage.query(0), Some("Layer 5".to_string()));
+    assert_eq!(version.image_coverage.query(1), Some("Layer 5".to_string()));
+    assert_eq!(version.image_coverage.query(2), Some("Layer 5".to_string()));
+    assert_eq!(version.image_coverage.query(4), Some("Layer 5".to_string()));
+    assert_eq!(version.image_coverage.query(5), Some("Layer 5".to_string()));
+    assert_eq!(version.image_coverage.query(7), Some("Layer 3".to_string()));
+    assert_eq!(version.image_coverage.query(8), Some("Layer 5".to_string()));
+
+    // After layer 6 insertion
+    let version = map.get_version(155).unwrap();
+    assert_eq!(version.image_coverage.query(0), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(1), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(2), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(4), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(5), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(7), Some("Layer 6".to_string()));
+    assert_eq!(version.image_coverage.query(8), Some("Layer 6".to_string()));
+}
+
+/// Wrapper for HistoricLayerCoverage that allows us to hack around the lack
+/// of support for retroactive insertion by rebuilding the map since the
+/// change.
+///
+/// Why is this needed? We most often insert new layers with newer LSNs,
+/// but during compaction we create layers with non-latest LSN, and during
+/// GC we delete historic layers.
+///
+/// Even though rebuilding is an expensive (N log N) solution to the problem,
+/// it's not critical since we do something equally expensive just to decide
+/// whether or not to create new image layers.
+/// TODO It's not expensive but it's not great to hold a layer map write lock
+///      for that long.
+///
+/// If this becomes an actual bottleneck, one solution would be to build a
+/// segment tree that holds PersistentLayerMaps. Though this would mean that
+/// we take an additional log(N) performance hit for queries, which will probably
+/// still be more critical.
+///
+/// See this for more on persistent and retroactive techniques:
+/// https://www.youtube.com/watch?v=WqCWghETNDc&t=581s
+pub struct BufferedHistoricLayerCoverage<Value> {
+    /// A persistent layer map that we rebuild when we need to retroactively update
+    historic_coverage: HistoricLayerCoverage<Value>,
+
+    /// We buffer insertion into the PersistentLayerMap to decrease the number of rebuilds.
+    buffer: BTreeMap<LayerKey, Option<Value>>,
+
+    /// All current layers. This is not used for search. Only to make rebuilds easier.
+    layers: BTreeMap<LayerKey, Value>,
+}
+
+impl<T: std::fmt::Debug> std::fmt::Debug for BufferedHistoricLayerCoverage<T> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("RetroactiveLayerMap")
+            .field("buffer", &self.buffer)
+            .field("layers", &self.layers)
+            .finish()
+    }
+}
+
+impl<T: Clone> Default for BufferedHistoricLayerCoverage<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<Value: Clone> BufferedHistoricLayerCoverage<Value> {
+    pub fn new() -> Self {
+        Self {
+            historic_coverage: HistoricLayerCoverage::<Value>::new(),
+            buffer: BTreeMap::new(),
+            layers: BTreeMap::new(),
+        }
+    }
+
+    pub fn insert(&mut self, layer_key: LayerKey, value: Value) {
+        self.buffer.insert(layer_key, Some(value));
+    }
+
+    pub fn remove(&mut self, layer_key: LayerKey) {
+        self.buffer.insert(layer_key, None);
+    }
+
+    pub fn rebuild(&mut self) {
+        // Find the first LSN that needs to be rebuilt
+        let rebuild_since: u64 = match self.buffer.iter().next() {
+            Some((LayerKey { lsn, .. }, _)) => lsn.start,
+            None => return, // No need to rebuild if buffer is empty
+        };
+
+        // Apply buffered updates to self.layers
+        let num_updates = self.buffer.len();
+        self.buffer.retain(|layer_key, layer| {
+            match layer {
+                Some(l) => {
+                    self.layers.insert(layer_key.clone(), l.clone());
+                }
+                None => {
+                    self.layers.remove(layer_key);
+                }
+            };
+            false
+        });
+
+        // Rebuild
+        let mut num_inserted = 0;
+        self.historic_coverage.trim(&rebuild_since);
+        for (layer_key, layer) in self.layers.range(
+            LayerKey {
+                lsn: rebuild_since..0,
+                key: 0..0,
+                is_image: false,
+            }..,
+        ) {
+            self.historic_coverage
+                .insert(layer_key.clone(), layer.clone());
+            num_inserted += 1;
+        }
+
+        // TODO maybe only warn if ratio is at least 10
+        info!(
+            "Rebuilt layer map. Did {} insertions to process a batch of {} updates.",
+            num_inserted, num_updates,
+        )
+    }
+
+    /// Iterate all the layers
+    pub fn iter(&self) -> impl '_ + Iterator<Item = Value> {
+        // NOTE we can actually perform this without rebuilding,
+        //      but it's not necessary for now.
+        if !self.buffer.is_empty() {
+            panic!("rebuild pls")
+        }
+
+        self.layers.values().cloned()
+    }
+
+    /// Return a reference to a queryable map, assuming all updates
+    /// have already been processed using self.rebuild()
+    pub fn get(&self) -> anyhow::Result<&HistoricLayerCoverage<Value>> {
+        // NOTE we error here instead of implicitly rebuilding because
+        //      rebuilding is somewhat expensive.
+        // TODO maybe implicitly rebuild and log/sentry an error?
+        if !self.buffer.is_empty() {
+            anyhow::bail!("rebuild required")
+        }
+
+        Ok(&self.historic_coverage)
+    }
+}
+
+#[test]
+fn test_retroactive_regression_1() {
+    let mut map = BufferedHistoricLayerCoverage::new();
+
+    map.insert(
+        LayerKey {
+            key: 0..21267647932558653966460912964485513215,
+            lsn: 23761336..23761457,
+            is_image: false,
+        },
+        "sdfsdfs".to_string(),
+    );
+
+    map.rebuild();
+
+    let version = map.get().unwrap().get_version(23761457).unwrap();
+    assert_eq!(
+        version.delta_coverage.query(100),
+        Some("sdfsdfs".to_string())
+    );
+}
+
+#[test]
+fn test_retroactive_simple() {
+    let mut map = BufferedHistoricLayerCoverage::new();
+
+    // Append some images in increasing LSN order
+    map.insert(
+        LayerKey {
+            key: 0..5,
+            lsn: 100..101,
+            is_image: true,
+        },
+        "Image 1".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 3..9,
+            lsn: 110..111,
+            is_image: true,
+        },
+        "Image 2".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 4..6,
+            lsn: 120..121,
+            is_image: true,
+        },
+        "Image 3".to_string(),
+    );
+    map.insert(
+        LayerKey {
+            key: 8..9,
+            lsn: 120..121,
+            is_image: true,
+        },
+        "Image 4".to_string(),
+    );
+
+    // Add a delta layer out of order
+    map.insert(
+        LayerKey {
+            key: 2..5,
+            lsn: 105..106,
+            is_image: true,
+        },
+        "Delta 1".to_string(),
+    );
+
+    // Rebuild so we can start querying
+    map.rebuild();
+
+    // Query key 4
+    let version = map.get().unwrap().get_version(90);
+    assert!(version.is_none());
+    let version = map.get().unwrap().get_version(102).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Image 1".to_string()));
+    let version = map.get().unwrap().get_version(107).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Delta 1".to_string()));
+    let version = map.get().unwrap().get_version(115).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Image 2".to_string()));
+    let version = map.get().unwrap().get_version(125).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Image 3".to_string()));
+
+    // Remove Image 3
+    map.remove(LayerKey {
+        key: 4..6,
+        lsn: 120..121,
+        is_image: true,
+    });
+    map.rebuild();
+
+    // Check deletion worked
+    let version = map.get().unwrap().get_version(125).unwrap();
+    assert_eq!(version.image_coverage.query(4), Some("Image 2".to_string()));
+    assert_eq!(version.image_coverage.query(8), Some("Image 4".to_string()));
+}

pageserver/src/tenant/layer_map/layer_coverage.rs

@@ -0,0 +1,154 @@
+use std::ops::Range;
+
+// TODO the `im` crate has 20x more downloads and also has
+// persistent/immutable BTree. It also runs a bit faster but
+// results are not the same on some tests.
+use rpds::RedBlackTreeMapSync;
+
+/// Data structure that can efficiently:
+/// - find the latest layer by lsn.end at a given key
+/// - iterate the latest layers in a key range
+/// - insert layers in non-decreasing lsn.start order
+///
+/// The struct is parameterized over Value for easier
+/// testing, but in practice it's some sort of layer.
+pub struct LayerCoverage<Value> {
+    /// For every change in coverage (as we sweep the key space)
+    /// we store (lsn.end, value).
+    ///
+    /// We use an immutable/persistent tree so that we can keep historic
+    /// versions of this coverage without cloning the whole thing and
+    /// incurring quadratic memory cost. See HistoricLayerCoverage.
+    ///
+    /// We use the Sync version of the map because we want Self to
+    /// be Sync. Using nonsync might be faster, if we can work with
+    /// that.
+    nodes: RedBlackTreeMapSync<i128, Option<(u64, Value)>>,
+}
+
+impl<T: Clone> Default for LayerCoverage<T> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<Value: Clone> LayerCoverage<Value> {
+    pub fn new() -> Self {
+        Self {
+            nodes: RedBlackTreeMapSync::default(),
+        }
+    }
+
+    /// Helper function to subdivide the key range without changing any values
+    ///
+    /// Complexity: O(log N)
+    fn add_node(&mut self, key: i128) {
+        let value = match self.nodes.range(..=key).last() {
+            Some((_, Some(v))) => Some(v.clone()),
+            Some((_, None)) => None,
+            None => None,
+        };
+        self.nodes.insert_mut(key, value);
+    }
+
+    /// Insert a layer.
+    ///
+    /// Complexity: worst case O(N), in practice O(log N). See NOTE in implementation.
+    pub fn insert(&mut self, key: Range<i128>, lsn: Range<u64>, value: Value) {
+        // Add nodes at endpoints
+        //
+        // NOTE The order of lines is important. We add nodes at the start
+        // and end of the key range **before updating any nodes** in order
+        // to pin down the current coverage outside of the relevant key range.
+        // Only the coverage inside the layer's key range should change.
+        self.add_node(key.start);
+        self.add_node(key.end);
+
+        // Raise the height where necessary
+        //
+        // NOTE This loop is worst case O(N), but amortized O(log N) in the special
+        // case when rectangles have no height. In practice I don't think we'll see
+        // the kind of layer intersections needed to trigger O(N) behavior. The worst
+        // case is N/2 horizontal layers overlapped with N/2 vertical layers in a
+        // grid pattern.
+        let mut to_update = Vec::new();
+        let mut to_remove = Vec::new();
+        let mut prev_covered = false;
+        for (k, node) in self.nodes.range(key.clone()) {
+            let needs_cover = match node {
+                None => true,
+                Some((h, _)) => h < &lsn.end,
+            };
+            if needs_cover {
+                match prev_covered {
+                    true => to_remove.push(*k),
+                    false => to_update.push(*k),
+                }
+            }
+            prev_covered = needs_cover;
+        }
+        if !prev_covered {
+            to_remove.push(key.end);
+        }
+        for k in to_update {
+            self.nodes.insert_mut(k, Some((lsn.end, value.clone())));
+        }
+        for k in to_remove {
+            self.nodes.remove_mut(&k);
+        }
+    }
+
+    /// Get the latest (by lsn.end) layer at a given key
+    ///
+    /// Complexity: O(log N)
+    pub fn query(&self, key: i128) -> Option<Value> {
+        self.nodes
+            .range(..=key)
+            .rev()
+            .next()?
+            .1
+            .as_ref()
+            .map(|(_, v)| v.clone())
+    }
+
+    /// Iterate the changes in layer coverage in a given range. You will likely
+    /// want to start with self.query(key.start), and then follow up with self.range
+    ///
+    /// Complexity: O(log N + result_size)
+    pub fn range(&self, key: Range<i128>) -> impl '_ + Iterator<Item = (i128, Option<Value>)> {
+        self.nodes
+            .range(key)
+            .map(|(k, v)| (*k, v.as_ref().map(|x| x.1.clone())))
+    }
+
+    /// O(1) clone
+    pub fn clone(&self) -> Self {
+        Self {
+            nodes: self.nodes.clone(),
+        }
+    }
+}
+
+/// Image and delta coverage at a specific LSN.
+pub struct LayerCoverageTuple<Value> {
+    pub image_coverage: LayerCoverage<Value>,
+    pub delta_coverage: LayerCoverage<Value>,
+}
+
+impl<T: Clone> Default for LayerCoverageTuple<T> {
+    fn default() -> Self {
+        Self {
+            image_coverage: LayerCoverage::default(),
+            delta_coverage: LayerCoverage::default(),
+        }
+    }
+}
+
+impl<Value: Clone> LayerCoverageTuple<Value> {
+    pub fn clone(&self) -> Self {
+        Self {
+            image_coverage: self.image_coverage.clone(),
+            delta_coverage: self.delta_coverage.clone(),
+        }
+    }
+}

pageserver/src/tenant/mgr.rs

@@ -16,6 +16,7 @@ use remote_storage::GenericRemoteStorage;
 use utils::crashsafe;
 
 use crate::config::PageServerConf;
+use crate::context::{DownloadBehavior, RequestContext};
 use crate::task_mgr::{self, TaskKind};
 use crate::tenant::config::TenantConfOpt;
 use crate::tenant::{Tenant, TenantState};
@@ -24,8 +25,35 @@ use crate::IGNORED_TENANT_FILE_NAME;
 use utils::fs_ext::PathExt;
 use utils::id::{TenantId, TimelineId};
 
-static TENANTS: Lazy<RwLock<HashMap<TenantId, Arc<Tenant>>>> =
-    Lazy::new(|| RwLock::new(HashMap::new()));
+/// The tenants known to the pageserver.
+/// The enum variants are used to distinguish the different states that the pageserver can be in.
+enum TenantsMap {
+    /// [`init_tenant_mgr`] is not done yet.
+    Initializing,
+    /// [`init_tenant_mgr`] is done, all on-disk tenants have been loaded.
+    /// New tenants can be added using [`tenant_map_insert`].
+    Open(HashMap<TenantId, Arc<Tenant>>),
+    /// The pageserver has entered shutdown mode via [`shutdown_all_tenants`].
+    /// Existing tenants are still accessible, but no new tenants can be created.
+    ShuttingDown(HashMap<TenantId, Arc<Tenant>>),
+}
+
+impl TenantsMap {
+    fn get(&self, tenant_id: &TenantId) -> Option<&Arc<Tenant>> {
+        match self {
+            TenantsMap::Initializing => None,
+            TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m.get(tenant_id),
+        }
+    }
+    fn remove(&mut self, tenant_id: &TenantId) -> Option<Arc<Tenant>> {
+        match self {
+            TenantsMap::Initializing => None,
+            TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m.remove(tenant_id),
+        }
+    }
+}
+
+static TENANTS: Lazy<RwLock<TenantsMap>> = Lazy::new(|| RwLock::new(TenantsMap::Initializing));
 
 /// Initialize repositories with locally available timelines.
 /// Timelines that are only partially available locally (remote storage has more data than this pageserver)
@@ -36,13 +64,16 @@ pub async fn init_tenant_mgr(
     remote_storage: Option<GenericRemoteStorage>,
 ) -> anyhow::Result<()> {
     // Scan local filesystem for attached tenants
-    let mut number_of_tenants = 0;
     let tenants_dir = conf.tenants_path();
 
+    let mut tenants = HashMap::new();
+
     let mut dir_entries = fs::read_dir(&tenants_dir)
         .await
         .with_context(|| format!("Failed to list tenants dir {tenants_dir:?}"))?;
 
+    let ctx = RequestContext::todo_child(TaskKind::Startup, DownloadBehavior::Warn);
+
     loop {
         match dir_entries.next_entry().await {
             Ok(None) => break,
@@ -86,10 +117,10 @@ pub async fn init_tenant_mgr(
                         conf,
                         &tenant_dir_path,
                         remote_storage.clone(),
+                        &ctx,
                     ) {
                         Ok(tenant) => {
-                            TENANTS.write().await.insert(tenant.tenant_id(), tenant);
-                            number_of_tenants += 1;
+                            tenants.insert(tenant.tenant_id(), tenant);
                         }
                         Err(e) => {
                             error!("Failed to collect tenant files from dir {tenants_dir:?} for entry {dir_entry:?}, reason: {e:#}");
@@ -108,7 +139,11 @@ pub async fn init_tenant_mgr(
         }
     }
 
-    info!("Processed {number_of_tenants} local tenants at startup");
+    info!("Processed {} local tenants at startup", tenants.len());
+
+    let mut tenants_map = TENANTS.write().await;
+    assert!(matches!(&*tenants_map, &TenantsMap::Initializing));
+    *tenants_map = TenantsMap::Open(tenants);
     Ok(())
 }
 
@@ -116,6 +151,7 @@ pub fn schedule_local_tenant_processing(
     conf: &'static PageServerConf,
     tenant_path: &Path,
     remote_storage: Option<GenericRemoteStorage>,
+    ctx: &RequestContext,
 ) -> anyhow::Result<Arc<Tenant>> {
     anyhow::ensure!(
         tenant_path.is_dir(),
@@ -150,7 +186,7 @@ pub fn schedule_local_tenant_processing(
     let tenant = if conf.tenant_attaching_mark_file_path(&tenant_id).exists() {
         info!("tenant {tenant_id} has attaching mark file, resuming its attach operation");
         if let Some(remote_storage) = remote_storage {
-            Tenant::spawn_attach(conf, tenant_id, remote_storage)
+            Tenant::spawn_attach(conf, tenant_id, remote_storage, ctx)
         } else {
             warn!("tenant {tenant_id} has attaching mark file, but pageserver has no remote storage configured");
             Tenant::create_broken_tenant(conf, tenant_id)
@@ -158,7 +194,7 @@ pub fn schedule_local_tenant_processing(
     } else {
         info!("tenant {tenant_id} is assumed to be loadable, starting load operation");
         // Start loading the tenant into memory. It will initially be in Loading state.
-        Tenant::spawn_load(conf, tenant_id, remote_storage)
+        Tenant::spawn_load(conf, tenant_id, remote_storage, ctx)
     };
     Ok(tenant)
 }
@@ -166,21 +202,44 @@ pub fn schedule_local_tenant_processing(
 ///
 /// Shut down all tenants. This runs as part of pageserver shutdown.
 ///
+/// NB: We leave the tenants in the map, so that they remain accessible through
+/// the management API until we shut it down. If we removed the shut-down tenants
+/// from the tenants map, the management API would return 404 for these tenants,
+/// because TenantsMap::get() now returns `None`.
+/// That could be easily misinterpreted by control plane, the consumer of the
+/// management API. For example, it could attach the tenant on a different pageserver.
+/// We would then be in split-brain once this pageserver restarts.
 pub async fn shutdown_all_tenants() {
+    // Prevent new tenants from being created.
     let tenants_to_shut_down = {
         let mut m = TENANTS.write().await;
-        let mut tenants_to_shut_down = Vec::with_capacity(m.len());
-        for (_, tenant) in m.drain() {
-            if tenant.is_active() {
-                // updates tenant state, forbidding new GC and compaction iterations from starting
-                tenant.set_stopping();
-                tenants_to_shut_down.push(tenant)
+        match &mut *m {
+            TenantsMap::Initializing => {
+                *m = TenantsMap::ShuttingDown(HashMap::default());
+                info!("tenants map is empty");
+                return;
+            }
+            TenantsMap::Open(tenants) => {
+                let tenants_clone = tenants.clone();
+                *m = TenantsMap::ShuttingDown(std::mem::take(tenants));
+                tenants_clone
+            }
+            TenantsMap::ShuttingDown(_) => {
+                error!("already shutting down, this function isn't supposed to be called more than once");
+                return;
             }
         }
-        drop(m);
-        tenants_to_shut_down
     };
 
+    let mut tenants_to_freeze_and_flush = Vec::with_capacity(tenants_to_shut_down.len());
+    for (_, tenant) in tenants_to_shut_down {
+        if tenant.is_active() {
+            // updates tenant state, forbidding new GC and compaction iterations from starting
+            tenant.set_stopping();
+            tenants_to_freeze_and_flush.push(tenant);
+        }
+    }
+
     // Shut down all existing walreceiver connections and stop accepting the new ones.
     task_mgr::shutdown_tasks(Some(TaskKind::WalReceiverManager), None, None).await;
 
@@ -192,7 +251,7 @@ pub async fn shutdown_all_tenants() {
     // should be no more activity in any of the repositories.
     //
     // On error, log it but continue with the shutdown for other tenants.
-    for tenant in tenants_to_shut_down {
+    for tenant in tenants_to_freeze_and_flush {
         let tenant_id = tenant.tenant_id();
         debug!("shutdown tenant {tenant_id}");
 
@@ -207,27 +266,23 @@ pub async fn create_tenant(
     tenant_conf: TenantConfOpt,
     tenant_id: TenantId,
     remote_storage: Option<GenericRemoteStorage>,
-) -> anyhow::Result<Option<Arc<Tenant>>> {
-    match TENANTS.write().await.entry(tenant_id) {
-        hash_map::Entry::Occupied(_) => {
-            debug!("tenant {tenant_id} already exists");
-            Ok(None)
-        }
-        hash_map::Entry::Vacant(v) => {
-            // Hold the write_tenants() lock, since all of this is local IO.
-            // If this section ever becomes contentious, introduce a new `TenantState::Creating`.
-            let tenant_directory = super::create_tenant_files(conf, tenant_conf, tenant_id)?;
-            let created_tenant =
-                schedule_local_tenant_processing(conf, &tenant_directory, remote_storage)?;
-            let crated_tenant_id = created_tenant.tenant_id();
-            anyhow::ensure!(
+    ctx: &RequestContext,
+) -> Result<Arc<Tenant>, TenantMapInsertError> {
+    tenant_map_insert(tenant_id, |vacant_entry| {
+        // We're holding the tenants lock in write mode while doing local IO.
+        // If this section ever becomes contentious, introduce a new `TenantState::Creating`
+        // and do the work in that state.
+        let tenant_directory = super::create_tenant_files(conf, tenant_conf, tenant_id)?;
+        let created_tenant =
+            schedule_local_tenant_processing(conf, &tenant_directory, remote_storage, ctx)?;
+        let crated_tenant_id = created_tenant.tenant_id();
+        anyhow::ensure!(
                 tenant_id == crated_tenant_id,
                 "loaded created tenant has unexpected tenant id (expect {tenant_id} != actual {crated_tenant_id})",
             );
-            v.insert(Arc::clone(&created_tenant));
-            Ok(Some(created_tenant))
-        }
-    }
+        vacant_entry.insert(Arc::clone(&created_tenant));
+        Ok(created_tenant)
+    }).await
 }
 
 pub async fn update_tenant_config(
@@ -260,10 +315,14 @@ pub async fn get_tenant(tenant_id: TenantId, active_only: bool) -> anyhow::Resul
     }
 }
 
-pub async fn delete_timeline(tenant_id: TenantId, timeline_id: TimelineId) -> anyhow::Result<()> {
+pub async fn delete_timeline(
+    tenant_id: TenantId,
+    timeline_id: TimelineId,
+    ctx: &RequestContext,
+) -> anyhow::Result<()> {
     match get_tenant(tenant_id, true).await {
         Ok(tenant) => {
-            tenant.delete_timeline(timeline_id).await?;
+            tenant.delete_timeline(timeline_id, ctx).await?;
         }
         Err(e) => anyhow::bail!("Cannot access tenant {tenant_id} in local tenant state: {e:?}"),
     }
@@ -291,8 +350,9 @@ pub async fn load_tenant(
     conf: &'static PageServerConf,
     tenant_id: TenantId,
     remote_storage: Option<GenericRemoteStorage>,
-) -> anyhow::Result<()> {
-    run_if_no_tenant_in_memory(tenant_id, |vacant_entry| {
+    ctx: &RequestContext,
+) -> Result<(), TenantMapInsertError> {
+    tenant_map_insert(tenant_id, |vacant_entry| {
         let tenant_path = conf.tenant_path(&tenant_id);
         let tenant_ignore_mark = conf.tenant_ignore_mark_file_path(tenant_id);
         if tenant_ignore_mark.exists() {
@@ -300,7 +360,7 @@ pub async fn load_tenant(
                 .with_context(|| format!("Failed to remove tenant ignore mark {tenant_ignore_mark:?} during tenant loading"))?;
         }
 
-        let new_tenant = schedule_local_tenant_processing(conf, &tenant_path, remote_storage)
+        let new_tenant = schedule_local_tenant_processing(conf, &tenant_path, remote_storage, ctx)
             .with_context(|| {
                 format!("Failed to schedule tenant processing in path {tenant_path:?}")
             })?;
@@ -329,16 +389,24 @@ pub async fn ignore_tenant(
     .await
 }
 
+#[derive(Debug, thiserror::Error)]
+pub enum TenantMapListError {
+    #[error("tenant map is still initiailizing")]
+    Initializing,
+}
+
 ///
 /// Get list of tenants, for the mgmt API
 ///
-pub async fn list_tenants() -> Vec<(TenantId, TenantState)> {
-    TENANTS
-        .read()
-        .await
-        .iter()
+pub async fn list_tenants() -> Result<Vec<(TenantId, TenantState)>, TenantMapListError> {
+    let tenants = TENANTS.read().await;
+    let m = match &*tenants {
+        TenantsMap::Initializing => return Err(TenantMapListError::Initializing),
+        TenantsMap::Open(m) | TenantsMap::ShuttingDown(m) => m,
+    };
+    Ok(m.iter()
         .map(|(id, tenant)| (*id, tenant.current_state()))
-        .collect()
+        .collect())
 }
 
 /// Execute Attach mgmt API command.
@@ -349,34 +417,62 @@ pub async fn attach_tenant(
     conf: &'static PageServerConf,
     tenant_id: TenantId,
     remote_storage: GenericRemoteStorage,
-) -> anyhow::Result<()> {
-    run_if_no_tenant_in_memory(tenant_id, |vacant_entry| {
+    ctx: &RequestContext,
+) -> Result<(), TenantMapInsertError> {
+    tenant_map_insert(tenant_id, |vacant_entry| {
         let tenant_path = conf.tenant_path(&tenant_id);
         anyhow::ensure!(
             !tenant_path.exists(),
             "Cannot attach tenant {tenant_id}, local tenant directory already exists"
         );
 
-        let tenant = Tenant::spawn_attach(conf, tenant_id, remote_storage);
+        let tenant = Tenant::spawn_attach(conf, tenant_id, remote_storage, ctx);
         vacant_entry.insert(tenant);
-
         Ok(())
     })
     .await
 }
 
-async fn run_if_no_tenant_in_memory<F, V>(tenant_id: TenantId, run: F) -> anyhow::Result<V>
+#[derive(Debug, thiserror::Error)]
+pub enum TenantMapInsertError {
+    #[error("tenant map is still initializing")]
+    StillInitializing,
+    #[error("tenant map is shutting down")]
+    ShuttingDown,
+    #[error("tenant {0} already exists, state: {1:?}")]
+    TenantAlreadyExists(TenantId, TenantState),
+    #[error(transparent)]
+    Closure(#[from] anyhow::Error),
+}
+
+/// Give the given closure access to the tenants map entry for the given `tenant_id`, iff that
+/// entry is vacant. The closure is responsible for creating the tenant object and inserting
+/// it into the tenants map through the vacnt entry that it receives as argument.
+///
+/// NB: the closure should return quickly because the current implementation of tenants map
+/// serializes access through an `RwLock`.
+async fn tenant_map_insert<F, V>(
+    tenant_id: TenantId,
+    insert_fn: F,
+) -> Result<V, TenantMapInsertError>
 where
     F: FnOnce(hash_map::VacantEntry<TenantId, Arc<Tenant>>) -> anyhow::Result<V>,
 {
-    match TENANTS.write().await.entry(tenant_id) {
-        hash_map::Entry::Occupied(e) => {
-            anyhow::bail!(
-                "tenant {tenant_id} already exists, state: {:?}",
-                e.get().current_state()
-            )
-        }
-        hash_map::Entry::Vacant(v) => run(v),
+    let mut guard = TENANTS.write().await;
+    let m = match &mut *guard {
+        TenantsMap::Initializing => return Err(TenantMapInsertError::StillInitializing),
+        TenantsMap::ShuttingDown(_) => return Err(TenantMapInsertError::ShuttingDown),
+        TenantsMap::Open(m) => m,
+    };
+    match m.entry(tenant_id) {
+        hash_map::Entry::Occupied(e) => Err(TenantMapInsertError::TenantAlreadyExists(
+            tenant_id,
+            e.get().current_state(),
+        )),
+        hash_map::Entry::Vacant(v) => match insert_fn(v) {
+            Ok(v) => Ok(v),
+            Err(e) => Err(TenantMapInsertError::Closure(e)),
+        },
     }
 }
 
@@ -449,9 +545,9 @@ pub async fn immediate_gc(
     tenant_id: TenantId,
     timeline_id: TimelineId,
     gc_req: TimelineGcRequest,
+    ctx: &RequestContext,
 ) -> Result<tokio::sync::oneshot::Receiver<Result<GcResult, anyhow::Error>>, ApiError> {
     let guard = TENANTS.read().await;
-
     let tenant = guard
         .get(&tenant_id)
         .map(Arc::clone)
@@ -462,7 +558,8 @@ pub async fn immediate_gc(
     // Use tenant's pitr setting
     let pitr = tenant.get_pitr_interval();
 
-    // Run in task_mgr to avoid race with detach operation
+    // Run in task_mgr to avoid race with tenant_detach operation
+    let ctx = ctx.detached_child(TaskKind::GarbageCollector, DownloadBehavior::Download);
     let (task_done, wait_task_done) = tokio::sync::oneshot::channel();
     task_mgr::spawn(
         &tokio::runtime::Handle::current(),
@@ -474,7 +571,7 @@ pub async fn immediate_gc(
         async move {
             fail::fail_point!("immediate_gc_task_pre");
             let result = tenant
-                .gc_iteration(Some(timeline_id), gc_horizon, pitr)
+                .gc_iteration(Some(timeline_id), gc_horizon, pitr, &ctx)
                 .instrument(info_span!("manual_gc", tenant = %tenant_id, timeline = %timeline_id))
                 .await;
                 // FIXME: `gc_iteration` can return an error for multiple reasons; we should handle it
@@ -497,6 +594,7 @@ pub async fn immediate_gc(
 pub async fn immediate_compact(
     tenant_id: TenantId,
     timeline_id: TimelineId,
+    ctx: &RequestContext,
 ) -> Result<tokio::sync::oneshot::Receiver<anyhow::Result<()>>, ApiError> {
     let guard = TENANTS.read().await;
 
@@ -510,7 +608,8 @@ pub async fn immediate_compact(
         .get_timeline(timeline_id, true)
         .map_err(ApiError::NotFound)?;
 
-    // Run in task_mgr to avoid race with detach operation
+    // Run in task_mgr to avoid race with tenant_detach operation
+    let ctx = ctx.detached_child(TaskKind::Compaction, DownloadBehavior::Download);
     let (task_done, wait_task_done) = tokio::sync::oneshot::channel();
     task_mgr::spawn(
         &tokio::runtime::Handle::current(),
@@ -523,7 +622,7 @@ pub async fn immediate_compact(
         false,
         async move {
             let result = timeline
-                .compact()
+                .compact(&ctx)
                 .instrument(
                     info_span!("manual_compact", tenant = %tenant_id, timeline = %timeline_id),
                 )

pageserver/src/tenant/remote_timeline_client.rs

@@ -135,7 +135,7 @@
 //! - Initiate upload queue with that [`IndexPart`].
 //! - Reschedule all lost operations by comparing the local filesystem state
 //!   and remote state as per [`IndexPart`]. This is done in
-//!   [`Timeline::setup_timeline`] and [`Timeline::reconcile_with_remote`].
+//!   [`Timeline::timeline_init_and_sync`] and [`Timeline::reconcile_with_remote`].
 //!
 //! Note that if we crash during file deletion between the index update
 //! that removes the file from the list of files, and deleting the remote file,
@@ -1010,7 +1010,10 @@ impl RemoteTimelineClient {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::tenant::harness::{TenantHarness, TIMELINE_ID};
+    use crate::{
+        tenant::harness::{TenantHarness, TIMELINE_ID},
+        DEFAULT_PG_VERSION,
+    };
     use remote_storage::{RemoteStorageConfig, RemoteStorageKind};
     use std::{collections::HashSet, path::Path};
     use utils::lsn::Lsn;
@@ -1064,9 +1067,19 @@ mod tests {
     // Test scheduling
     #[test]
     fn upload_scheduling() -> anyhow::Result<()> {
+        // Use a current-thread runtime in the test
+        let runtime = Box::leak(Box::new(
+            tokio::runtime::Builder::new_current_thread()
+                .enable_all()
+                .build()?,
+        ));
+        let _entered = runtime.enter();
+
         let harness = TenantHarness::create("upload_scheduling")?;
+        let (tenant, ctx) = runtime.block_on(harness.load());
+        let _timeline =
+            tenant.create_empty_timeline(TIMELINE_ID, Lsn(0), DEFAULT_PG_VERSION, &ctx)?;
         let timeline_path = harness.timeline_path(&TIMELINE_ID);
-        std::fs::create_dir_all(&timeline_path)?;
 
         let remote_fs_dir = harness.conf.workdir.join("remote_fs");
         std::fs::create_dir_all(remote_fs_dir)?;
@@ -1084,14 +1097,6 @@ mod tests {
             storage: RemoteStorageKind::LocalFs(remote_fs_dir.clone()),
         };
 
-        // Use a current-thread runtime in the test
-        let runtime = Box::leak(Box::new(
-            tokio::runtime::Builder::new_current_thread()
-                .enable_all()
-                .build()?,
-        ));
-        let _entered = runtime.enter();
-
         // Test outline:
         //
         // Schedule upload of a bunch of layers. Check that they are started immediately, not queued

pageserver/src/tenant/size.rs

@@ -6,6 +6,7 @@ use anyhow::Context;
 use tokio::sync::oneshot::error::RecvError;
 use tokio::sync::Semaphore;
 
+use crate::context::RequestContext;
 use crate::pgdatadir_mapping::CalculateLogicalSizeError;
 
 use super::Tenant;
@@ -23,7 +24,13 @@ use tracing::*;
 pub struct ModelInputs {
     updates: Vec<Update>,
     retention_period: u64,
+
+    /// Relevant lsns per timeline.
+    ///
+    /// This field is not required for deserialization purposes, which is mostly used in tests. The
+    /// LSNs explain the outcome (updates) but are not needed in size calculation.
     #[serde_as(as = "HashMap<serde_with::DisplayFromStr, _>")]
+    #[serde(default)]
     timeline_inputs: HashMap<TimelineId, TimelineInputs>,
 }
 
@@ -32,6 +39,8 @@ pub struct ModelInputs {
 #[serde_with::serde_as]
 #[derive(Debug, serde::Serialize, serde::Deserialize)]
 struct TimelineInputs {
+    #[serde_as(as = "serde_with::DisplayFromStr")]
+    ancestor_lsn: Lsn,
     #[serde_as(as = "serde_with::DisplayFromStr")]
     last_record: Lsn,
     #[serde_as(as = "serde_with::DisplayFromStr")]
@@ -44,6 +53,116 @@ struct TimelineInputs {
     next_gc_cutoff: Lsn,
 }
 
+// Adjust BranchFrom sorting so that we always process ancestor
+// before descendants. This is needed to correctly calculate size of
+// descendant timelines.
+//
+// Note that we may have multiple BranchFroms at the same LSN, so we
+// need to sort them in the tree order.
+//
+// see updates_sort_with_branches_at_same_lsn test below
+fn sort_updates_in_tree_order(updates: Vec<Update>) -> anyhow::Result<Vec<Update>> {
+    let mut sorted_updates = Vec::with_capacity(updates.len());
+    let mut known_timelineids = HashSet::new();
+    let mut i = 0;
+    while i < updates.len() {
+        let curr_upd = &updates[i];
+
+        if let Command::BranchFrom(parent_id) = curr_upd.command {
+            let parent_id = match parent_id {
+                Some(parent_id) if known_timelineids.contains(&parent_id) => {
+                    // we have already processed ancestor
+                    // process this BranchFrom Update normally
+                    known_timelineids.insert(curr_upd.timeline_id);
+                    sorted_updates.push(*curr_upd);
+                    i += 1;
+                    continue;
+                }
+                None => {
+                    known_timelineids.insert(curr_upd.timeline_id);
+                    sorted_updates.push(*curr_upd);
+                    i += 1;
+                    continue;
+                }
+                Some(parent_id) => parent_id,
+            };
+
+            let mut j = i;
+
+            // we have not processed ancestor yet.
+            // there is a chance that it is at the same Lsn
+            if !known_timelineids.contains(&parent_id) {
+                let mut curr_lsn_branchfroms: HashMap<TimelineId, Vec<(TimelineId, usize)>> =
+                    HashMap::new();
+
+                // inspect all branchpoints at the same lsn
+                while j < updates.len() && updates[j].lsn == curr_upd.lsn {
+                    let lookahead_upd = &updates[j];
+                    j += 1;
+
+                    if let Command::BranchFrom(lookahead_parent_id) = lookahead_upd.command {
+                        match lookahead_parent_id {
+                            Some(lookahead_parent_id)
+                                if !known_timelineids.contains(&lookahead_parent_id) =>
+                            {
+                                // we have not processed ancestor yet
+                                // store it for later
+                                let es =
+                                    curr_lsn_branchfroms.entry(lookahead_parent_id).or_default();
+                                es.push((lookahead_upd.timeline_id, j));
+                            }
+                            _ => {
+                                // we have already processed ancestor
+                                // process this BranchFrom Update normally
+                                known_timelineids.insert(lookahead_upd.timeline_id);
+                                sorted_updates.push(*lookahead_upd);
+                            }
+                        }
+                    }
+                }
+
+                // process BranchFroms in the tree order
+                // check that we don't have a cycle if somet entry is orphan
+                // (this should not happen, but better to be safe)
+                let mut processed_some_entry = true;
+                while processed_some_entry {
+                    processed_some_entry = false;
+
+                    curr_lsn_branchfroms.retain(|parent_id, branchfroms| {
+                        if known_timelineids.contains(parent_id) {
+                            for (timeline_id, j) in branchfroms {
+                                known_timelineids.insert(*timeline_id);
+                                sorted_updates.push(updates[*j - 1]);
+                            }
+                            processed_some_entry = true;
+                            false
+                        } else {
+                            true
+                        }
+                    });
+                }
+
+                if !curr_lsn_branchfroms.is_empty() {
+                    // orphans are expected to be rare and transient between tenant reloads
+                    // for example, an broken ancestor without the child branch being broken.
+                    anyhow::bail!(
+                        "orphan branch(es) detected in BranchFroms: {curr_lsn_branchfroms:?}"
+                    );
+                }
+            }
+
+            assert!(j > i);
+            i = j;
+        } else {
+            // not a BranchFrom, keep the same order
+            sorted_updates.push(*curr_upd);
+            i += 1;
+        }
+    }
+
+    Ok(sorted_updates)
+}
+
 /// Gathers the inputs for the tenant sizing model.
 ///
 /// Tenant size does not consider the latest state, but only the state until next_gc_cutoff, which
@@ -63,24 +182,26 @@ pub(super) async fn gather_inputs(
     tenant: &Tenant,
     limit: &Arc<Semaphore>,
     logical_size_cache: &mut HashMap<(TimelineId, Lsn), u64>,
+    ctx: &RequestContext,
 ) -> anyhow::Result<ModelInputs> {
     // with joinset, on drop, all of the tasks will just be de-scheduled, which we can use to
     // our advantage with `?` error handling.
     let mut joinset = tokio::task::JoinSet::new();
 
-    let timelines = tenant
-        .refresh_gc_info()
+    // refresh is needed to update gc related pitr_cutoff and horizon_cutoff
+    tenant
+        .refresh_gc_info(ctx)
         .await
         .context("Failed to refresh gc_info before gathering inputs")?;
 
+    let timelines = tenant.list_timelines();
+
     if timelines.is_empty() {
-        // All timelines are below tenant's gc_horizon; alternative would be to use
-        // Tenant::list_timelines but then those gc_info's would not be updated yet, possibly
-        // missing GcInfo::retain_lsns or having obsolete values for cutoff's.
+        // perhaps the tenant has just been created, and as such doesn't have any data yet
         return Ok(ModelInputs {
             updates: vec![],
             retention_period: 0,
-            timeline_inputs: HashMap::new(),
+            timeline_inputs: HashMap::default(),
         });
     }
 
@@ -91,13 +212,25 @@ pub(super) async fn gather_inputs(
 
     let mut updates = Vec::new();
 
-    // record the per timline values used to determine `retention_period`
+    // record the per timeline values useful to debug the model inputs, also used to track
+    // ancestor_lsn without keeping a hold of Timeline
     let mut timeline_inputs = HashMap::with_capacity(timelines.len());
 
     // used to determine the `retention_period` for the size model
     let mut max_cutoff_distance = None;
 
+    // mapping from (TimelineId, Lsn) => if this branch point has been handled already via
+    // GcInfo::retain_lsns or if it needs to have its logical_size calculated.
+    let mut referenced_branch_froms = HashMap::<(TimelineId, Lsn), bool>::new();
+
     for timeline in timelines {
+        if !timeline.is_active() {
+            anyhow::bail!(
+                "timeline {} is not active, cannot calculate tenant_size now",
+                timeline.timeline_id
+            );
+        }
+
         let last_record_lsn = timeline.get_last_record_lsn();
 
         let (interesting_lsns, horizon_cutoff, pitr_cutoff, next_gc_cutoff) = {
@@ -163,13 +296,30 @@ pub(super) async fn gather_inputs(
 
         // all timelines branch from something, because it might be impossible to pinpoint
         // which is the tenant_size_model's "default" branch.
+
+        let ancestor_lsn = timeline.get_ancestor_lsn();
+
         updates.push(Update {
-            lsn: timeline.get_ancestor_lsn(),
+            lsn: ancestor_lsn,
             command: Command::BranchFrom(timeline.get_ancestor_timeline_id()),
             timeline_id: timeline.timeline_id,
         });
 
+        if let Some(parent_timeline_id) = timeline.get_ancestor_timeline_id() {
+            // refresh_gc_info will update branchpoints and pitr_cutoff but only do it for branches
+            // which are over gc_horizon. for example, a "main" branch which never received any
+            // updates apart from initdb not have branch points recorded.
+            referenced_branch_froms
+                .entry((parent_timeline_id, timeline.get_ancestor_lsn()))
+                .or_default();
+        }
+
         for (lsn, _kind) in &interesting_lsns {
+            // mark this visited so don't need to re-process this parent
+            *referenced_branch_froms
+                .entry((timeline.timeline_id, *lsn))
+                .or_default() = true;
+
             if let Some(size) = logical_size_cache.get(&(timeline.timeline_id, *lsn)) {
                 updates.push(Update {
                     lsn: *lsn,
@@ -181,26 +331,20 @@ pub(super) async fn gather_inputs(
             } else {
                 let timeline = Arc::clone(&timeline);
                 let parallel_size_calcs = Arc::clone(limit);
-                joinset.spawn(calculate_logical_size(parallel_size_calcs, timeline, *lsn));
+                let ctx = ctx.attached_child();
+                joinset.spawn(calculate_logical_size(
+                    parallel_size_calcs,
+                    timeline,
+                    *lsn,
+                    ctx,
+                ));
             }
         }
 
-        // all timelines also have an end point if they have made any progress
-        if last_record_lsn > timeline.get_ancestor_lsn()
-            && !interesting_lsns
-                .iter()
-                .any(|(lsn, _)| lsn == &last_record_lsn)
-        {
-            updates.push(Update {
-                lsn: last_record_lsn,
-                command: Command::EndOfBranch,
-                timeline_id: timeline.timeline_id,
-            });
-        }
-
         timeline_inputs.insert(
             timeline.timeline_id,
             TimelineInputs {
+                ancestor_lsn,
                 last_record: last_record_lsn,
                 // this is not used above, because it might not have updated recently enough
                 latest_gc_cutoff: *timeline.get_latest_gc_cutoff_lsn(),
@@ -211,6 +355,81 @@ pub(super) async fn gather_inputs(
         );
     }
 
+    // iterate over discovered branch points and make sure we are getting logical sizes at those
+    // points.
+    for ((timeline_id, lsn), handled) in referenced_branch_froms.iter() {
+        if *handled {
+            continue;
+        }
+
+        let timeline_id = *timeline_id;
+        let lsn = *lsn;
+
+        match timeline_inputs.get(&timeline_id) {
+            Some(inputs) if inputs.ancestor_lsn == lsn => {
+                // we don't need an update at this branch point which is also point where
+                // timeline_id branch was branched from.
+                continue;
+            }
+            Some(_) => {}
+            None => {
+                // we should have this because we have iterated through all of the timelines
+                anyhow::bail!("missing timeline_input for {timeline_id}")
+            }
+        }
+
+        if let Some(size) = logical_size_cache.get(&(timeline_id, lsn)) {
+            updates.push(Update {
+                lsn,
+                timeline_id,
+                command: Command::Update(*size),
+            });
+
+            needed_cache.insert((timeline_id, lsn));
+        } else {
+            let timeline = tenant
+                .get_timeline(timeline_id, false)
+                .context("find referenced ancestor timeline")?;
+            let parallel_size_calcs = Arc::clone(limit);
+            joinset.spawn(calculate_logical_size(
+                parallel_size_calcs,
+                timeline.clone(),
+                lsn,
+                ctx.attached_child(),
+            ));
+
+            if let Some(parent_id) = timeline.get_ancestor_timeline_id() {
+                // we should not find new ones because we iterated tenants all timelines
+                anyhow::ensure!(
+                    timeline_inputs.contains_key(&parent_id),
+                    "discovered new timeline {parent_id} (parent of {timeline_id})"
+                );
+            }
+        };
+    }
+
+    // finally add in EndOfBranch for all timelines where their last_record_lsn is not a branch
+    // point. this is needed by the model.
+    for (timeline_id, inputs) in timeline_inputs.iter() {
+        let lsn = inputs.last_record;
+
+        if referenced_branch_froms.contains_key(&(*timeline_id, lsn)) {
+            // this means that the (timeline_id, last_record_lsn) represents a branch point
+            // we do not want to add EndOfBranch updates for these points because it doesn't fit
+            // into the current tenant_size_model.
+            continue;
+        }
+
+        if lsn > inputs.ancestor_lsn {
+            // all timelines also have an end point if they have made any progress
+            updates.push(Update {
+                lsn,
+                command: Command::EndOfBranch,
+                timeline_id: *timeline_id,
+            });
+        }
+    }
+
     let mut have_any_error = false;
 
     while let Some(res) = joinset.join_next().await {
@@ -267,8 +486,13 @@ pub(super) async fn gather_inputs(
     // for branch points, which come as multiple updates at the same LSN, the Command::Update
     // is needed before a branch is made out of that branch Command::BranchFrom. this is
     // handled by the variant order in `Command`.
+    //
     updates.sort_unstable();
 
+    // And another sort to handle Command::BranchFrom ordering
+    // in case when there are multiple branches at the same LSN.
+    let sorted_updates = sort_updates_in_tree_order(updates)?;
+
     let retention_period = match max_cutoff_distance {
         Some(max) => max.0,
         None => {
@@ -277,7 +501,7 @@ pub(super) async fn gather_inputs(
     };
 
     Ok(ModelInputs {
-        updates,
+        updates: sorted_updates,
         retention_period,
         timeline_inputs,
     })
@@ -295,21 +519,23 @@ impl ModelInputs {
                 command: op,
                 timeline_id,
             } = update;
+
             let Lsn(now) = *lsn;
             match op {
                 Command::Update(sz) => {
-                    storage.insert_point(&Some(*timeline_id), "".into(), now, Some(*sz));
+                    storage.insert_point(&Some(*timeline_id), "".into(), now, Some(*sz))?;
                 }
                 Command::EndOfBranch => {
-                    storage.insert_point(&Some(*timeline_id), "".into(), now, None);
+                    storage.insert_point(&Some(*timeline_id), "".into(), now, None)?;
                 }
                 Command::BranchFrom(parent) => {
-                    storage.branch(parent, Some(*timeline_id));
+                    // This branch command may fail if it cannot find a parent to branch from.
+                    storage.branch(parent, Some(*timeline_id))?;
                 }
             }
         }
 
-        Ok(storage.calculate(self.retention_period).total_children())
+        Ok(storage.calculate(self.retention_period)?.total_children())
     }
 }
 
@@ -365,13 +591,15 @@ async fn calculate_logical_size(
     limit: Arc<tokio::sync::Semaphore>,
     timeline: Arc<crate::tenant::Timeline>,
     lsn: utils::lsn::Lsn,
+    ctx: RequestContext,
 ) -> Result<TimelineAtLsnSizeResult, RecvError> {
     let _permit = tokio::sync::Semaphore::acquire_owned(limit)
         .await
         .expect("global semaphore should not had been closed");
 
     let size_res = timeline
-        .spawn_ondemand_logical_size_calculation(lsn)
+        .spawn_ondemand_logical_size_calculation(lsn, ctx)
+        .instrument(info_span!("spawn_ondemand_logical_size_calculation"))
         .await?;
     Ok(TimelineAtLsnSizeResult(timeline, lsn, size_res))
 }
@@ -457,9 +685,146 @@ fn updates_sort() {
 fn verify_size_for_multiple_branches() {
     // this is generated from integration test test_tenant_size_with_multiple_branches, but this way
     // it has the stable lsn's
-    let doc = r#"{"updates":[{"lsn":"0/0","command":{"branch_from":null},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/176FA40","command":{"update":25763840},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/176FA40","command":{"branch_from":"cd9d9409c216e64bf580904facedb01b"},"timeline_id":"10b532a550540bc15385eac4edde416a"},{"lsn":"0/1819818","command":{"update":26075136},"timeline_id":"10b532a550540bc15385eac4edde416a"},{"lsn":"0/18B5E40","command":{"update":26427392},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/18D3DF0","command":{"update":26492928},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/18D3DF0","command":{"branch_from":"cd9d9409c216e64bf580904facedb01b"},"timeline_id":"230fc9d756f7363574c0d66533564dcc"},{"lsn":"0/220F438","command":{"update":25239552},"timeline_id":"230fc9d756f7363574c0d66533564dcc"}],"retention_period":131072,"timeline_inputs":{"cd9d9409c216e64bf580904facedb01b":{"last_record":"0/18D5E40","latest_gc_cutoff":"0/169ACF0","horizon_cutoff":"0/18B5E40","pitr_cutoff":"0/18B5E40","next_gc_cutoff":"0/18B5E40"},"10b532a550540bc15385eac4edde416a":{"last_record":"0/1839818","latest_gc_cutoff":"0/169ACF0","horizon_cutoff":"0/1819818","pitr_cutoff":"0/1819818","next_gc_cutoff":"0/1819818"},"230fc9d756f7363574c0d66533564dcc":{"last_record":"0/222F438","latest_gc_cutoff":"0/169ACF0","horizon_cutoff":"0/220F438","pitr_cutoff":"0/220F438","next_gc_cutoff":"0/220F438"}}}"#;
+    //
+    // timelineinputs have been left out, because those explain the inputs, but don't participate
+    // in further size calculations.
+    let doc = r#"{"updates":[{"lsn":"0/0","command":{"branch_from":null},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/176FA40","command":{"update":25763840},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/176FA40","command":{"branch_from":"cd9d9409c216e64bf580904facedb01b"},"timeline_id":"10b532a550540bc15385eac4edde416a"},{"lsn":"0/1819818","command":{"update":26075136},"timeline_id":"10b532a550540bc15385eac4edde416a"},{"lsn":"0/18B5E40","command":{"update":26427392},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/18D3DF0","command":{"update":26492928},"timeline_id":"cd9d9409c216e64bf580904facedb01b"},{"lsn":"0/18D3DF0","command":{"branch_from":"cd9d9409c216e64bf580904facedb01b"},"timeline_id":"230fc9d756f7363574c0d66533564dcc"},{"lsn":"0/220F438","command":{"update":25239552},"timeline_id":"230fc9d756f7363574c0d66533564dcc"}],"retention_period":131072}"#;
 
     let inputs: ModelInputs = serde_json::from_str(doc).unwrap();
 
     assert_eq!(inputs.calculate().unwrap(), 36_409_872);
 }
+
+#[test]
+fn updates_sort_with_branches_at_same_lsn() {
+    use std::str::FromStr;
+    use Command::{BranchFrom, EndOfBranch};
+
+    macro_rules! lsn {
+        ($e:expr) => {
+            Lsn::from_str($e).unwrap()
+        };
+    }
+
+    let ids = [
+        TimelineId::from_str("00000000000000000000000000000000").unwrap(),
+        TimelineId::from_str("11111111111111111111111111111111").unwrap(),
+        TimelineId::from_str("22222222222222222222222222222222").unwrap(),
+        TimelineId::from_str("33333333333333333333333333333333").unwrap(),
+        TimelineId::from_str("44444444444444444444444444444444").unwrap(),
+    ];
+
+    // issue https://github.com/neondatabase/neon/issues/3179
+    let commands = vec![
+        Update {
+            lsn: lsn!("0/0"),
+            command: BranchFrom(None),
+            timeline_id: ids[0],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: Command::Update(25387008),
+            timeline_id: ids[0],
+        },
+        // next three are wrongly sorted, because
+        // ids[1] is branched from before ids[1] exists
+        // and ids[2] is branched from before ids[2] exists
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[1])),
+            timeline_id: ids[3],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[0])),
+            timeline_id: ids[2],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[2])),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/1CA85B8"),
+            command: Command::Update(28925952),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/1CD85B8"),
+            command: Command::Update(29024256),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/1CD85B8"),
+            command: BranchFrom(Some(ids[1])),
+            timeline_id: ids[4],
+        },
+        Update {
+            lsn: lsn!("0/22DCE70"),
+            command: Command::Update(32546816),
+            timeline_id: ids[3],
+        },
+        Update {
+            lsn: lsn!("0/230CE70"),
+            command: EndOfBranch,
+            timeline_id: ids[3],
+        },
+    ];
+
+    let expected = vec![
+        Update {
+            lsn: lsn!("0/0"),
+            command: BranchFrom(None),
+            timeline_id: ids[0],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: Command::Update(25387008),
+            timeline_id: ids[0],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[0])),
+            timeline_id: ids[2],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[2])),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/169AD58"),
+            command: BranchFrom(Some(ids[1])),
+            timeline_id: ids[3],
+        },
+        Update {
+            lsn: lsn!("0/1CA85B8"),
+            command: Command::Update(28925952),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/1CD85B8"),
+            command: Command::Update(29024256),
+            timeline_id: ids[1],
+        },
+        Update {
+            lsn: lsn!("0/1CD85B8"),
+            command: BranchFrom(Some(ids[1])),
+            timeline_id: ids[4],
+        },
+        Update {
+            lsn: lsn!("0/22DCE70"),
+            command: Command::Update(32546816),
+            timeline_id: ids[3],
+        },
+        Update {
+            lsn: lsn!("0/230CE70"),
+            command: EndOfBranch,
+            timeline_id: ids[3],
+        },
+    ];
+
+    let sorted_commands = sort_updates_in_tree_order(commands).unwrap();
+
+    assert_eq!(sorted_commands, expected);
+}

pageserver/src/tenant/storage_layer.rs

@@ -196,3 +196,50 @@ pub fn downcast_remote_layer(
         None
     }
 }
+
+impl std::fmt::Debug for dyn Layer {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("Layer")
+            .field("short_id", &self.short_id())
+            .finish()
+    }
+}
+
+/// Holds metadata about a layer without any content. Used mostly for testing.
+pub struct LayerDescriptor {
+    pub key: Range<Key>,
+    pub lsn: Range<Lsn>,
+    pub is_incremental: bool,
+    pub short_id: String,
+}
+
+impl Layer for LayerDescriptor {
+    fn get_key_range(&self) -> Range<Key> {
+        self.key.clone()
+    }
+
+    fn get_lsn_range(&self) -> Range<Lsn> {
+        self.lsn.clone()
+    }
+
+    fn is_incremental(&self) -> bool {
+        self.is_incremental
+    }
+
+    fn get_value_reconstruct_data(
+        &self,
+        _key: Key,
+        _lsn_range: Range<Lsn>,
+        _reconstruct_data: &mut ValueReconstructState,
+    ) -> Result<ValueReconstructResult> {
+        todo!("This method shouldn't be part of the Layer trait")
+    }
+
+    fn short_id(&self) -> String {
+        self.short_id.clone()
+    }
+
+    fn dump(&self, _verbose: bool) -> Result<()> {
+        todo!()
+    }
+}

pageserver/src/tenant/tasks.rs

@@ -5,6 +5,7 @@ use std::ops::ControlFlow;
 use std::sync::Arc;
 use std::time::Duration;
 
+use crate::context::{DownloadBehavior, RequestContext};
 use crate::metrics::TENANT_TASK_EVENTS;
 use crate::task_mgr;
 use crate::task_mgr::{TaskKind, BACKGROUND_RUNTIME};
@@ -52,19 +53,20 @@ async fn compaction_loop(tenant_id: TenantId) {
     info!("starting");
     TENANT_TASK_EVENTS.with_label_values(&["start"]).inc();
     async {
+        let ctx = RequestContext::todo_child(TaskKind::Compaction, DownloadBehavior::Download);
         loop {
             trace!("waking up");
 
             let tenant = tokio::select! {
                 _ = task_mgr::shutdown_watcher() => {
                     info!("received cancellation request");
-                    return;
+                return;
                 },
                 tenant_wait_result = wait_for_active_tenant(tenant_id, wait_duration) => match tenant_wait_result {
                     ControlFlow::Break(()) => return,
                     ControlFlow::Continue(tenant) => tenant,
                 },
-            };
+        };
 
             let mut sleep_duration = tenant.get_compaction_period();
             if sleep_duration == Duration::ZERO {
@@ -73,7 +75,7 @@ async fn compaction_loop(tenant_id: TenantId) {
                 sleep_duration = Duration::from_secs(10);
             } else {
                 // Run compaction
-                if let Err(e) = tenant.compaction_iteration().await {
+                if let Err(e) = tenant.compaction_iteration(&ctx).await {
                     sleep_duration = wait_duration;
                     error!("Compaction failed, retrying in {:?}: {e:?}", sleep_duration);
                 }
@@ -103,6 +105,9 @@ async fn gc_loop(tenant_id: TenantId) {
     info!("starting");
     TENANT_TASK_EVENTS.with_label_values(&["start"]).inc();
     async {
+        // GC might require downloading, to find the cutoff LSN that corresponds to the
+        // cutoff specified as time.
+        let ctx = RequestContext::todo_child(TaskKind::GarbageCollector, DownloadBehavior::Download);
         loop {
             trace!("waking up");
 
@@ -127,7 +132,7 @@ async fn gc_loop(tenant_id: TenantId) {
             } else {
                 // Run gc
                 if gc_horizon > 0 {
-                    if let Err(e) = tenant.gc_iteration(None, gc_horizon, tenant.get_pitr_interval()).await
+                    if let Err(e) = tenant.gc_iteration(None, gc_horizon, tenant.get_pitr_interval(), &ctx).await
                     {
                         sleep_duration = wait_duration;
                         error!("Gc failed, retrying in {:?}: {e:?}", sleep_duration);

pageserver/src/tenant/timeline.rs

@@ -3,12 +3,12 @@
 use anyhow::{anyhow, bail, ensure, Context};
 use bytes::Bytes;
 use fail::fail_point;
-use futures::stream::FuturesUnordered;
 use futures::StreamExt;
 use itertools::Itertools;
 use once_cell::sync::OnceCell;
 use pageserver_api::models::{
-    DownloadRemoteLayersTaskInfo, DownloadRemoteLayersTaskState, TimelineState,
+    DownloadRemoteLayersTaskInfo, DownloadRemoteLayersTaskSpawnRequest,
+    DownloadRemoteLayersTaskState, TimelineState,
 };
 use tokio::sync::{oneshot, watch, Semaphore, TryAcquireError};
 use tokio_util::sync::CancellationToken;
@@ -23,6 +23,7 @@ use std::sync::atomic::{AtomicI64, Ordering as AtomicOrdering};
 use std::sync::{Arc, Mutex, MutexGuard, RwLock, Weak};
 use std::time::{Duration, Instant, SystemTime};
 
+use crate::context::{DownloadBehavior, RequestContext};
 use crate::tenant::remote_timeline_client::{self, index::LayerFileMetadata};
 use crate::tenant::storage_layer::{
     DeltaFileName, DeltaLayerWriter, ImageFileName, ImageLayerWriter, InMemoryLayer, LayerFileName,
@@ -377,6 +378,12 @@ pub enum PageReconstructError {
     #[error(transparent)]
     Other(#[from] anyhow::Error), // source and Display delegate to anyhow::Error
 
+    /// The operation would require downloading a layer that is missing locally.
+    NeedsDownload(Weak<Timeline>, Weak<RemoteLayer>),
+
+    /// The operation was cancelled
+    Cancelled,
+
     /// An error happened replaying WAL records
     #[error(transparent)]
     WalRedo(#[from] crate::walredo::WalRedoError),
@@ -386,6 +393,19 @@ impl std::fmt::Debug for PageReconstructError {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
         match self {
             Self::Other(err) => err.fmt(f),
+            Self::NeedsDownload(_tli, _layer) => write!(f, "needs download"),
+            Self::Cancelled => write!(f, "cancelled"),
+            Self::WalRedo(err) => err.fmt(f),
+        }
+    }
+}
+
+impl std::fmt::Display for PageReconstructError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
+        match self {
+            Self::Other(err) => err.fmt(f),
+            Self::NeedsDownload(_tli, _layer) => write!(f, "needs download"),
+            Self::Cancelled => write!(f, "cancelled"),
             Self::WalRedo(err) => err.fmt(f),
         }
     }
@@ -422,11 +442,24 @@ impl Timeline {
     /// an ancestor branch, for example, or waste a lot of cycles chasing the
     /// non-existing key.
     ///
-    pub async fn get(&self, key: Key, lsn: Lsn) -> Result<Bytes, PageReconstructError> {
+    pub async fn get(
+        &self,
+        key: Key,
+        lsn: Lsn,
+        ctx: &RequestContext,
+    ) -> Result<Bytes, PageReconstructError> {
         if !lsn.is_valid() {
             return Err(PageReconstructError::Other(anyhow::anyhow!("Invalid LSN")));
         }
 
+        // XXX: structured stats collection for layer eviction here.
+        trace!(
+            "get page request for {}@{} from task kind {:?}",
+            key,
+            lsn,
+            ctx.task_kind()
+        );
+
         // Check the page cache. We will get back the most recent page with lsn <= `lsn`.
         // The cached image can be returned directly if there is no WAL between the cached image
         // and requested LSN. The cached image can also be used to reduce the amount of WAL needed
@@ -450,7 +483,7 @@ impl Timeline {
             img: cached_page_img,
         };
 
-        self.get_reconstruct_data(key, lsn, &mut reconstruct_state)
+        self.get_reconstruct_data(key, lsn, &mut reconstruct_state, ctx)
             .await?;
 
         self.metrics
@@ -513,13 +546,25 @@ impl Timeline {
     /// You should call this before any of the other get_* or list_* functions. Calling
     /// those functions with an LSN that has been processed yet is an error.
     ///
-    pub async fn wait_lsn(&self, lsn: Lsn) -> anyhow::Result<()> {
+    pub async fn wait_lsn(
+        &self,
+        lsn: Lsn,
+        _ctx: &RequestContext, /* Prepare for use by cancellation */
+    ) -> anyhow::Result<()> {
         anyhow::ensure!(self.is_active(), "Cannot wait for Lsn on inactive timeline");
 
         // This should never be called from the WAL receiver, because that could lead
         // to a deadlock.
         anyhow::ensure!(
-            task_mgr::current_task_kind() != Some(TaskKind::WalReceiverConnection),
+            task_mgr::current_task_kind() != Some(TaskKind::WalReceiverManager),
+            "wait_lsn cannot be called in WAL receiver"
+        );
+        anyhow::ensure!(
+            task_mgr::current_task_kind() != Some(TaskKind::WalReceiverConnectionHandler),
+            "wait_lsn cannot be called in WAL receiver"
+        );
+        anyhow::ensure!(
+            task_mgr::current_task_kind() != Some(TaskKind::WalReceiverConnectionPoller),
             "wait_lsn cannot be called in WAL receiver"
         );
 
@@ -558,7 +603,7 @@ impl Timeline {
         self.flush_frozen_layers_and_wait().await
     }
 
-    pub async fn compact(&self) -> anyhow::Result<()> {
+    pub async fn compact(&self, ctx: &RequestContext) -> anyhow::Result<()> {
         let last_record_lsn = self.get_last_record_lsn();
 
         // Last record Lsn could be zero in case the timeline was just created
@@ -616,14 +661,16 @@ impl Timeline {
             .repartition(
                 self.get_last_record_lsn(),
                 self.get_compaction_target_size(),
+                ctx,
             )
             .await
         {
             Ok((partitioning, lsn)) => {
                 // 2. Create new image layers for partitions that have been modified
                 // "enough".
-                let layer_paths_to_upload =
-                    self.create_image_layers(&partitioning, lsn, false).await?;
+                let layer_paths_to_upload = self
+                    .create_image_layers(&partitioning, lsn, false, ctx)
+                    .await?;
                 if let Some(remote_client) = &self.remote_client {
                     for (path, layer_metadata) in layer_paths_to_upload {
                         remote_client.schedule_layer_file_upload(&path, &layer_metadata)?;
@@ -673,7 +720,10 @@ impl Timeline {
     /// the initial size calculation has not been run (gets triggered on the first size access).
     ///
     /// return size and boolean flag that shows if the size is exact
-    pub fn get_current_logical_size(self: &Arc<Self>) -> anyhow::Result<(u64, bool)> {
+    pub fn get_current_logical_size(
+        self: &Arc<Self>,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<(u64, bool)> {
         let current_size = self.current_logical_size.current_size()?;
         debug!("Current size: {current_size:?}");
 
@@ -683,7 +733,7 @@ impl Timeline {
             (current_size, self.current_logical_size.initial_part_end)
         {
             is_exact = false;
-            self.try_spawn_size_init_task(init_lsn);
+            self.try_spawn_size_init_task(init_lsn, ctx);
         }
 
         Ok((size, is_exact))
@@ -729,16 +779,24 @@ impl Timeline {
         Ok(())
     }
 
+    pub fn activate(self: &Arc<Self>) {
+        self.set_state(TimelineState::Active);
+        self.launch_wal_receiver();
+    }
+
     pub fn set_state(&self, new_state: TimelineState) {
         match (self.current_state(), new_state) {
             (equal_state_1, equal_state_2) if equal_state_1 == equal_state_2 => {
-                debug!("Ignoring new state, equal to the existing one: {equal_state_2:?}");
+                warn!("Ignoring new state, equal to the existing one: {equal_state_2:?}");
+            }
+            (st, TimelineState::Loading) => {
+                error!("ignoring transition from {st:?} into Loading state");
             }
             (TimelineState::Broken, _) => {
                 error!("Ignoring state update {new_state:?} for broken tenant");
             }
             (TimelineState::Stopping, TimelineState::Active) => {
-                debug!("Not activating a Stopping timeline");
+                error!("Not activating a Stopping timeline");
             }
             (_, new_state) => {
                 self.state.send_replace(new_state);
@@ -812,7 +870,7 @@ impl Timeline {
         pg_version: u32,
     ) -> Arc<Self> {
         let disk_consistent_lsn = metadata.disk_consistent_lsn();
-        let (state, _) = watch::channel(TimelineState::Suspended);
+        let (state, _) = watch::channel(TimelineState::Loading);
 
         let (layer_flush_start_tx, _) = tokio::sync::watch::channel(0);
         let (layer_flush_done_tx, _) = tokio::sync::watch::channel((0, Ok(())));
@@ -909,22 +967,25 @@ impl Timeline {
 
         let layer_flush_start_rx = self.layer_flush_start_tx.subscribe();
         let self_clone = Arc::clone(self);
+
         info!("spawning flush loop");
         task_mgr::spawn(
-                    task_mgr::BACKGROUND_RUNTIME.handle(),
-                    task_mgr::TaskKind::LayerFlushTask,
-                    Some(self.tenant_id),
-                    Some(self.timeline_id),
-                    "layer flush task",
-                    false,
-                    async move {
-                         self_clone.flush_loop(layer_flush_start_rx).await;
-                         let mut flush_loop_state = self_clone.flush_loop_state.lock().unwrap();
-                         assert_eq!(*flush_loop_state, FlushLoopState::Running);
-                         *flush_loop_state  = FlushLoopState::Exited;
-                         Ok(()) }
-                    .instrument(info_span!(parent: None, "layer flush task", tenant = %self.tenant_id, timeline = %self.timeline_id))
-                );
+            task_mgr::BACKGROUND_RUNTIME.handle(),
+            task_mgr::TaskKind::LayerFlushTask,
+            Some(self.tenant_id),
+            Some(self.timeline_id),
+            "layer flush task",
+            false,
+            async move {
+                let background_ctx = RequestContext::todo_child(TaskKind::LayerFlushTask, DownloadBehavior::Error);
+                self_clone.flush_loop(layer_flush_start_rx, &background_ctx).await;
+                let mut flush_loop_state = self_clone.flush_loop_state.lock().unwrap();
+                assert_eq!(*flush_loop_state, FlushLoopState::Running);
+                *flush_loop_state  = FlushLoopState::Exited;
+                Ok(())
+            }
+            .instrument(info_span!(parent: None, "layer flush task", tenant = %self.tenant_id, timeline = %self.timeline_id))
+        );
 
         *flush_loop_state = FlushLoopState::Running;
     }
@@ -955,12 +1016,16 @@ impl Timeline {
             .unwrap_or(self.conf.default_tenant_conf.max_lsn_wal_lag);
         drop(tenant_conf_guard);
         let self_clone = Arc::clone(self);
+        let background_ctx =
+            // XXX: this is a detached_child. Plumb through the ctx from call sites.
+            RequestContext::todo_child(TaskKind::WalReceiverManager, DownloadBehavior::Error);
         spawn_connection_manager_task(
             self_clone,
             walreceiver_connect_timeout,
             lagging_wal_timeout,
             max_lsn_wal_lag,
             crate::config::SAFEKEEPER_AUTH_TOKEN.get().cloned(),
+            background_ctx,
         );
     }
 
@@ -970,6 +1035,7 @@ impl Timeline {
     ///
     pub(super) fn load_layer_map(&self, disk_consistent_lsn: Lsn) -> anyhow::Result<()> {
         let mut layers = self.layers.write().unwrap();
+        let mut updates = layers.batch_update();
         let mut num_layers = 0;
 
         let timer = self.metrics.load_layer_map_histo.start_timer();
@@ -1010,7 +1076,7 @@ impl Timeline {
 
                 trace!("found layer {}", layer.path().display());
                 total_physical_size += file_size;
-                layers.insert_historic(Arc::new(layer));
+                updates.insert_historic(Arc::new(layer));
                 num_layers += 1;
             } else if let Some(deltafilename) = DeltaFileName::parse_str(&fname) {
                 // Create a DeltaLayer struct for each delta file.
@@ -1041,7 +1107,7 @@ impl Timeline {
 
                 trace!("found layer {}", layer.path().display());
                 total_physical_size += file_size;
-                layers.insert_historic(Arc::new(layer));
+                updates.insert_historic(Arc::new(layer));
                 num_layers += 1;
             } else if fname == METADATA_FILE_NAME || fname.ends_with(".old") {
                 // ignore these
@@ -1067,6 +1133,7 @@ impl Timeline {
             }
         }
 
+        updates.flush();
         layers.next_open_layer_at = Some(Lsn(disk_consistent_lsn.0) + 1);
 
         info!(
@@ -1091,6 +1158,11 @@ impl Timeline {
         // Are we missing some files that are present in remote storage?
         // Create RemoteLayer instances for them.
         let mut local_only_layers = local_layers;
+
+        // We're holding a layer map lock for a while but this
+        // method is only called during init so it's fine.
+        let mut layer_map = self.layers.write().unwrap();
+        let mut updates = layer_map.batch_update();
         for remote_layer_name in &index_part.timeline_layers {
             let local_layer = local_only_layers.remove(remote_layer_name);
 
@@ -1129,7 +1201,7 @@ impl Timeline {
                             anyhow::bail!("could not rename file {local_layer_path:?}: {err:?}");
                         } else {
                             self.metrics.resident_physical_size_gauge.sub(local_size);
-                            self.layers.write().unwrap().remove_historic(local_layer);
+                            updates.remove_historic(local_layer);
                             // fall-through to adding the remote layer
                         }
                     } else {
@@ -1171,7 +1243,7 @@ impl Timeline {
                     );
                     let remote_layer = Arc::new(remote_layer);
 
-                    self.layers.write().unwrap().insert_historic(remote_layer);
+                    updates.insert_historic(remote_layer);
                 }
                 LayerFileName::Delta(deltafilename) => {
                     // Create a RemoteLayer for the delta file.
@@ -1194,13 +1266,14 @@ impl Timeline {
                         &remote_layer_metadata,
                     );
                     let remote_layer = Arc::new(remote_layer);
-                    self.layers.write().unwrap().insert_historic(remote_layer);
+                    updates.insert_historic(remote_layer);
                 }
                 #[cfg(test)]
                 LayerFileName::Test(_) => unreachable!(),
             }
         }
 
+        updates.flush();
         Ok(local_only_layers)
     }
 
@@ -1280,7 +1353,7 @@ impl Timeline {
         Ok(())
     }
 
-    fn try_spawn_size_init_task(self: &Arc<Self>, init_lsn: Lsn) {
+    fn try_spawn_size_init_task(self: &Arc<Self>, init_lsn: Lsn, ctx: &RequestContext) {
         let permit = match Arc::clone(&self.current_logical_size.initial_size_computation)
             .try_acquire_owned()
         {
@@ -1296,8 +1369,18 @@ impl Timeline {
             .initial_logical_size
             .get()
             .is_none());
+
+        info!(
+            "spawning logical size computation from context of task kind {:?}",
+            ctx.task_kind()
+        );
         // We need to start the computation task.
+        // It gets a separate context since it will outlive the request that called this function.
         let self_clone = Arc::clone(self);
+        let background_ctx = ctx.detached_child(
+            TaskKind::InitialLogicalSizeCalculation,
+            DownloadBehavior::Download,
+        );
         task_mgr::spawn(
             task_mgr::BACKGROUND_RUNTIME.handle(),
             task_mgr::TaskKind::InitialLogicalSizeCalculation,
@@ -1307,7 +1390,9 @@ impl Timeline {
             false,
             // NB: don't log errors here, task_mgr will do that.
             async move {
-                let calculated_size = match self_clone.logical_size_calculation_task(init_lsn).await
+                let calculated_size = match self_clone
+                    .logical_size_calculation_task(init_lsn, &background_ctx)
+                    .await
                 {
                     Ok(s) => s,
                     Err(CalculateLogicalSizeError::Cancelled) => {
@@ -1342,18 +1427,27 @@ impl Timeline {
     pub fn spawn_ondemand_logical_size_calculation(
         self: &Arc<Self>,
         lsn: Lsn,
+        ctx: RequestContext,
     ) -> oneshot::Receiver<Result<u64, CalculateLogicalSizeError>> {
         let (sender, receiver) = oneshot::channel();
         let self_clone = Arc::clone(self);
+        // XXX if our caller loses interest, i.e., ctx is cancelled,
+        // we should stop the size calculation work and return an error.
+        // That would require restructuring this function's API to
+        // return the result directly, instead of a Receiver for the result.
+        let ctx = ctx.detached_child(
+            TaskKind::OndemandLogicalSizeCalculation,
+            DownloadBehavior::Download,
+        );
         task_mgr::spawn(
             task_mgr::BACKGROUND_RUNTIME.handle(),
-            task_mgr::TaskKind::InitialLogicalSizeCalculation,
+            task_mgr::TaskKind::OndemandLogicalSizeCalculation,
             Some(self.tenant_id),
             Some(self.timeline_id),
             "ondemand logical size calculation",
             false,
             async move {
-                let res = self_clone.logical_size_calculation_task(lsn).await;
+                let res = self_clone.logical_size_calculation_task(lsn, &ctx).await;
                 let _ = sender.send(res).ok();
                 Ok(()) // Receiver is responsible for handling errors
             },
@@ -1365,6 +1459,7 @@ impl Timeline {
     async fn logical_size_calculation_task(
         self: &Arc<Self>,
         init_lsn: Lsn,
+        ctx: &RequestContext,
     ) -> Result<u64, CalculateLogicalSizeError> {
         let mut timeline_state_updates = self.subscribe_for_state_updates();
         let self_calculation = Arc::clone(self);
@@ -1372,12 +1467,13 @@ impl Timeline {
 
         let calculation = async {
             let cancel = cancel.child_token();
+            let ctx = ctx.attached_child();
             tokio::task::spawn_blocking(move || {
                 // Run in a separate thread since this can do a lot of
                 // synchronous file IO without .await inbetween
                 // if there are no RemoteLayers that would require downloading.
                 let h = tokio::runtime::Handle::current();
-                h.block_on(self_calculation.calculate_logical_size(init_lsn, cancel))
+                h.block_on(self_calculation.calculate_logical_size(init_lsn, cancel, &ctx))
             })
             .await
             .context("Failed to spawn calculation result task")?
@@ -1392,7 +1488,7 @@ impl Timeline {
                             TimelineState::Active => continue,
                             TimelineState::Broken
                             | TimelineState::Stopping
-                            | TimelineState::Suspended => {
+                            | TimelineState::Loading => {
                                 break format!("aborted because timeline became inactive (new state: {new_state:?})")
                             }
                         }
@@ -1432,10 +1528,11 @@ impl Timeline {
     ///
     /// NOTE: counted incrementally, includes ancestors. This can be a slow operation,
     /// especially if we need to download remote layers.
-    async fn calculate_logical_size(
+    pub async fn calculate_logical_size(
         &self,
         up_to_lsn: Lsn,
         cancel: CancellationToken,
+        ctx: &RequestContext,
     ) -> Result<u64, CalculateLogicalSizeError> {
         info!(
             "Calculating logical size for timeline {} at {}",
@@ -1478,7 +1575,7 @@ impl Timeline {
             self.metrics.logical_size_histo.start_timer()
         };
         let logical_size = self
-            .get_current_logical_size_non_incremental(up_to_lsn, cancel)
+            .get_current_logical_size_non_incremental(up_to_lsn, cancel, ctx)
             .await?;
         debug!("calculated logical size: {logical_size}");
         timer.stop_and_record();
@@ -1555,6 +1652,7 @@ impl Timeline {
         key: Key,
         request_lsn: Lsn,
         reconstruct_state: &mut ValueReconstructState,
+        ctx: &RequestContext,
     ) -> Result<(), PageReconstructError> {
         // Start from the current timeline.
         let mut timeline_owned;
@@ -1742,14 +1840,43 @@ impl Timeline {
                 let remote_layer_as_persistent: Arc<dyn PersistentLayer> =
                     Arc::clone(&remote_layer) as Arc<dyn PersistentLayer>;
                 let id = remote_layer_as_persistent.traversal_id();
-                info!("need remote layer {id}");
+                info!(
+                    "need remote layer {} for task kind {:?}",
+                    id,
+                    ctx.task_kind()
+                );
 
                 // The next layer doesn't exist locally. Need to download it.
                 // (The control flow is a bit complicated here because we must drop the 'layers'
                 // lock before awaiting on the Future.)
-                info!("on-demand downloading remote layer {id}");
-                timeline.download_remote_layer(remote_layer).await?;
-                continue 'layer_map_search;
+                match (
+                    ctx.download_behavior(),
+                    self.conf.ondemand_download_behavior_treat_error_as_warn,
+                ) {
+                    (DownloadBehavior::Download, _) => {
+                        info!(
+                            "on-demand downloading remote layer {id} for task kind {:?}",
+                            ctx.task_kind()
+                        );
+                        timeline.download_remote_layer(remote_layer).await?;
+                        continue 'layer_map_search;
+                    }
+                    (DownloadBehavior::Warn, _) | (DownloadBehavior::Error, true) => {
+                        warn!(
+                            "unexpectedly on-demand downloading remote layer {} for task kind {:?}",
+                            id,
+                            ctx.task_kind()
+                        );
+                        timeline.download_remote_layer(remote_layer).await?;
+                        continue 'layer_map_search;
+                    }
+                    (DownloadBehavior::Error, false) => {
+                        return Err(PageReconstructError::NeedsDownload(
+                            timeline.myself.clone(),
+                            Arc::downgrade(&remote_layer),
+                        ))
+                    }
+                }
             }
         }
     }
@@ -1871,7 +1998,11 @@ impl Timeline {
     }
 
     /// Layer flusher task's main loop.
-    async fn flush_loop(&self, mut layer_flush_start_rx: tokio::sync::watch::Receiver<u64>) {
+    async fn flush_loop(
+        &self,
+        mut layer_flush_start_rx: tokio::sync::watch::Receiver<u64>,
+        ctx: &RequestContext,
+    ) {
         info!("started flush loop");
         loop {
             tokio::select! {
@@ -1892,7 +2023,7 @@ impl Timeline {
                     // drop 'layers' lock to allow concurrent reads and writes
                 };
                 if let Some(layer_to_flush) = layer_to_flush {
-                    if let Err(err) = self.flush_frozen_layer(layer_to_flush).await {
+                    if let Err(err) = self.flush_frozen_layer(layer_to_flush, ctx).await {
                         error!("could not flush frozen layer: {err:?}");
                         break Err(err);
                     }
@@ -1957,8 +2088,12 @@ impl Timeline {
     }
 
     /// Flush one frozen in-memory layer to disk, as a new delta layer.
-    #[instrument(skip(self, frozen_layer), fields(tenant_id=%self.tenant_id, timeline_id=%self.timeline_id, layer=%frozen_layer.short_id()))]
-    async fn flush_frozen_layer(&self, frozen_layer: Arc<InMemoryLayer>) -> anyhow::Result<()> {
+    #[instrument(skip(self, frozen_layer, ctx), fields(tenant_id=%self.tenant_id, timeline_id=%self.timeline_id, layer=%frozen_layer.short_id()))]
+    async fn flush_frozen_layer(
+        &self,
+        frozen_layer: Arc<InMemoryLayer>,
+        ctx: &RequestContext,
+    ) -> anyhow::Result<()> {
         // As a special case, when we have just imported an image into the repository,
         // instead of writing out a L0 delta layer, we directly write out image layer
         // files instead. This is possible as long as *all* the data imported into the
@@ -1966,10 +2101,12 @@ impl Timeline {
         let lsn_range = frozen_layer.get_lsn_range();
         let layer_paths_to_upload =
             if lsn_range.start == self.initdb_lsn && lsn_range.end == Lsn(self.initdb_lsn.0 + 1) {
+                // Note: The 'ctx' in use here has DownloadBehavior::Error. We should not
+                // require downloading anything during initial import.
                 let (partitioning, _lsn) = self
-                    .repartition(self.initdb_lsn, self.get_compaction_target_size())
+                    .repartition(self.initdb_lsn, self.get_compaction_target_size(), ctx)
                     .await?;
-                self.create_image_layers(&partitioning, self.initdb_lsn, true)
+                self.create_image_layers(&partitioning, self.initdb_lsn, true, ctx)
                     .await?
             } else {
                 // normal case, write out a L0 delta layer file.
@@ -2099,10 +2236,11 @@ impl Timeline {
         ])?;
 
         // Add it to the layer map
-        {
-            let mut layers = self.layers.write().unwrap();
-            layers.insert_historic(Arc::new(new_delta));
-        }
+        self.layers
+            .write()
+            .unwrap()
+            .batch_update()
+            .insert_historic(Arc::new(new_delta));
 
         // update the timeline's physical size
         let sz = new_delta_path.metadata()?.len();
@@ -2119,6 +2257,7 @@ impl Timeline {
         &self,
         lsn: Lsn,
         partition_size: u64,
+        ctx: &RequestContext,
     ) -> anyhow::Result<(KeyPartitioning, Lsn)> {
         {
             let partitioning_guard = self.partitioning.lock().unwrap();
@@ -2129,7 +2268,7 @@ impl Timeline {
                 return Ok((partitioning_guard.0.clone(), partitioning_guard.1));
             }
         }
-        let keyspace = self.collect_keyspace(lsn).await?;
+        let keyspace = self.collect_keyspace(lsn, ctx).await?;
         let partitioning = keyspace.partition(partition_size);
 
         let mut partitioning_guard = self.partitioning.lock().unwrap();
@@ -2166,13 +2305,15 @@ impl Timeline {
                 // are some delta layers *later* than current 'lsn', if more WAL was processed and flushed
                 // after we read last_record_lsn, which is passed here in the 'lsn' argument.
                 if img_lsn < lsn {
-                    let num_deltas = layers.count_deltas(&img_range, &(img_lsn..lsn))?;
+                    let threshold = self.get_image_creation_threshold();
+                    let num_deltas =
+                        layers.count_deltas(&img_range, &(img_lsn..lsn), Some(threshold))?;
 
                     debug!(
                         "key range {}-{}, has {} deltas on this timeline in LSN range {}..{}",
                         img_range.start, img_range.end, num_deltas, img_lsn, lsn
                     );
-                    if num_deltas >= self.get_image_creation_threshold() {
+                    if num_deltas >= threshold {
                         return Ok(true);
                     }
                 }
@@ -2187,6 +2328,7 @@ impl Timeline {
         partitioning: &KeyPartitioning,
         lsn: Lsn,
         force: bool,
+        ctx: &RequestContext,
     ) -> Result<HashMap<LayerFileName, LayerFileMetadata>, PageReconstructError> {
         let timer = self.metrics.create_images_time_histo.start_timer();
         let mut image_layers: Vec<ImageLayer> = Vec::new();
@@ -2211,7 +2353,7 @@ impl Timeline {
                 for range in &partition.ranges {
                     let mut key = range.start;
                     while key < range.end {
-                        let img = match self.get(key, lsn).await {
+                        let img = match self.get(key, lsn, ctx).await {
                             Ok(img) => img,
                             Err(err) => {
                                 // If we fail to reconstruct a VM or FSM page, we can zero the
@@ -2267,21 +2409,23 @@ impl Timeline {
         let mut layer_paths_to_upload = HashMap::with_capacity(image_layers.len());
 
         let mut layers = self.layers.write().unwrap();
+        let mut updates = layers.batch_update();
         let timeline_path = self.conf.timeline_path(&self.timeline_id, &self.tenant_id);
         for l in image_layers {
             let path = l.filename();
             let metadata = timeline_path
                 .join(path.file_name())
                 .metadata()
-                .context("reading metadata of layer file {path}")?;
+                .with_context(|| format!("reading metadata of layer file {}", path.file_name()))?;
 
             layer_paths_to_upload.insert(path, LayerFileMetadata::new(metadata.len()));
 
             self.metrics
                 .resident_physical_size_gauge
                 .add(metadata.len());
-            layers.insert_historic(Arc::new(l));
+            updates.insert_historic(Arc::new(l));
         }
+        updates.flush();
         drop(layers);
         timer.stop_and_record();
 
@@ -2577,6 +2721,7 @@ impl Timeline {
         }
 
         let mut layers = self.layers.write().unwrap();
+        let mut updates = layers.batch_update();
         let mut new_layer_paths = HashMap::with_capacity(new_layers.len());
         for l in new_layers {
             let new_delta_path = l.path();
@@ -2597,7 +2742,7 @@ impl Timeline {
 
             new_layer_paths.insert(new_delta_path, LayerFileMetadata::new(metadata.len()));
             let x: Arc<dyn PersistentLayer + 'static> = Arc::new(l);
-            layers.insert_historic(x);
+            updates.insert_historic(x);
         }
 
         // Now that we have reshuffled the data to set of new delta layers, we can
@@ -2611,8 +2756,9 @@ impl Timeline {
             }
             layer_names_to_delete.push(l.filename());
             l.delete()?;
-            layers.remove_historic(l);
+            updates.remove_historic(l);
         }
+        updates.flush();
         drop(layers);
 
         // Also schedule the deletions in remote storage
@@ -2662,6 +2808,7 @@ impl Timeline {
         retain_lsns: Vec<Lsn>,
         cutoff_horizon: Lsn,
         pitr: Duration,
+        ctx: &RequestContext,
     ) -> anyhow::Result<()> {
         // First, calculate pitr_cutoff_timestamp and then convert it to LSN.
         //
@@ -2674,7 +2821,7 @@ impl Timeline {
             if let Some(pitr_cutoff_timestamp) = now.checked_sub(pitr) {
                 let pitr_timestamp = to_pg_timestamp(pitr_cutoff_timestamp);
 
-                match self.find_lsn_for_timestamp(pitr_timestamp).await? {
+                match self.find_lsn_for_timestamp(pitr_timestamp, ctx).await? {
                     LsnForTimestamp::Present(lsn) => lsn,
                     LsnForTimestamp::Future(lsn) => {
                         // The timestamp is in the future. That sounds impossible,
@@ -2812,6 +2959,7 @@ impl Timeline {
         // 3. it doesn't need to be retained for 'retain_lsns';
         // 4. newer on-disk image layers cover the layer's whole key range
         //
+        // TODO holding a write lock is too agressive and avoidable
         let mut layers = self.layers.write().unwrap();
         'outer: for l in layers.iter_historic_layers() {
             result.layers_total += 1;
@@ -2843,6 +2991,8 @@ impl Timeline {
             // might be referenced by child branches forever.
             // We can track this in child timeline GC and delete parent layers when
             // they are no longer needed. This might be complicated with long inheritance chains.
+            //
+            // TODO Vec is not a great choice for `retain_lsns`
             for retain_lsn in &retain_lsns {
                 // start_lsn is inclusive
                 if &l.get_lsn_range().start <= retain_lsn {
@@ -2896,6 +3046,7 @@ impl Timeline {
             layers_to_remove.push(Arc::clone(&l));
         }
 
+        let mut updates = layers.batch_update();
         if !layers_to_remove.is_empty() {
             // Persist the new GC cutoff value in the metadata file, before
             // we actually remove anything.
@@ -2913,7 +3064,13 @@ impl Timeline {
                 }
                 layer_names_to_delete.push(doomed_layer.filename());
                 doomed_layer.delete()?; // FIXME: schedule succeeded deletions before returning?
-                layers.remove_historic(doomed_layer);
+
+                // TODO Removing from the bottom of the layer map is expensive.
+                //      Maybe instead discard all layer map historic versions that
+                //      won't be needed for page reconstruction for this timeline,
+                //      and mark what we can't delete yet as deleted from the layer
+                //      map index without actually rebuilding the index.
+                updates.remove_historic(doomed_layer);
                 result.layers_removed += 1;
             }
 
@@ -2925,6 +3082,7 @@ impl Timeline {
                 remote_client.schedule_layer_file_deletion(&layer_names_to_delete)?;
             }
         }
+        updates.flush();
 
         info!(
             "GC completed removing {} layers, cutoff {}",
@@ -3081,11 +3239,13 @@ impl Timeline {
                     // Delta- or ImageLayer in the layer map.
                     let new_layer = remote_layer.create_downloaded_layer(self_clone.conf, *size);
                     let mut layers = self_clone.layers.write().unwrap();
+                    let mut updates = layers.batch_update();
                     {
                         let l: Arc<dyn PersistentLayer> = remote_layer.clone();
-                        layers.remove_historic(l);
+                        updates.remove_historic(l);
                     }
-                    layers.insert_historic(new_layer);
+                    updates.insert_historic(new_layer);
+                    updates.flush();
                     drop(layers);
 
                     // Now that we've inserted the download into the layer map,
@@ -3116,6 +3276,7 @@ impl Timeline {
 
     pub async fn spawn_download_all_remote_layers(
         self: Arc<Self>,
+        request: DownloadRemoteLayersTaskSpawnRequest,
     ) -> Result<DownloadRemoteLayersTaskInfo, DownloadRemoteLayersTaskInfo> {
         let mut status_guard = self.download_all_remote_layers_task_info.write().unwrap();
         if let Some(st) = &*status_guard {
@@ -3139,7 +3300,7 @@ impl Timeline {
             "download all remote layers task",
             false,
             async move {
-                self_clone.download_all_remote_layers().await;
+                self_clone.download_all_remote_layers(request).await;
                 let mut status_guard = self_clone.download_all_remote_layers_task_info.write().unwrap();
                  match &mut *status_guard {
                     None => {
@@ -3171,15 +3332,23 @@ impl Timeline {
         Ok(initial_info)
     }
 
-    async fn download_all_remote_layers(self: &Arc<Self>) {
-        let mut downloads: FuturesUnordered<_> = {
+    async fn download_all_remote_layers(
+        self: &Arc<Self>,
+        request: DownloadRemoteLayersTaskSpawnRequest,
+    ) {
+        let mut downloads = Vec::new();
+        {
             let layers = self.layers.read().unwrap();
             layers
                 .iter_historic_layers()
                 .filter_map(|l| l.downcast_remote_layer())
                 .map(|l| self.download_remote_layer(l))
-                .collect()
-        };
+                .for_each(|dl| downloads.push(dl))
+        }
+        let total_layer_count = downloads.len();
+        // limit download concurrency as specified in request
+        let downloads = futures::stream::iter(downloads);
+        let mut downloads = downloads.buffer_unordered(request.max_concurrent_downloads.get());
 
         macro_rules! lock_status {
             ($st:ident) => {
@@ -3200,7 +3369,7 @@ impl Timeline {
 
         {
             lock_status!(st);
-            st.total_layer_count = downloads.len().try_into().unwrap();
+            st.total_layer_count = total_layer_count as u64;
         }
         loop {
             tokio::select! {

pageserver/src/walreceiver.rs

@@ -116,6 +116,10 @@ impl<E: Clone> TaskHandle<E> {
         let join_handle = WALRECEIVER_RUNTIME.spawn(async move {
             events_sender.send(TaskStateUpdate::Started).ok();
             task(events_sender, cancellation_clone).await
+            // events_sender is dropped at some point during the .await above.
+            // But the task is still running on WALRECEIVER_RUNTIME.
+            // That is the window when `!jh.is_finished()`
+            // is true inside `fn next_task_event()` below.
         });
 
         TaskHandle {
@@ -132,7 +136,23 @@ impl<E: Clone> TaskHandle<E> {
                 TaskEvent::End(match self.join_handle.as_mut() {
                     Some(jh) => {
                         if !jh.is_finished() {
-                            warn!("sender is dropped while join handle is still alive");
+                            // 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");
                         }
 
                         let res = jh

pageserver/src/walreceiver/connection_manager.rs

@@ -11,6 +11,7 @@
 
 use std::{collections::HashMap, num::NonZeroU64, ops::ControlFlow, sync::Arc, time::Duration};
 
+use crate::context::RequestContext;
 use crate::task_mgr::TaskKind;
 use crate::task_mgr::WALRECEIVER_RUNTIME;
 use crate::tenant::Timeline;
@@ -46,6 +47,7 @@ pub fn spawn_connection_manager_task(
     lagging_wal_timeout: Duration,
     max_lsn_wal_lag: NonZeroU64,
     auth_token: Option<Arc<String>>,
+    ctx: RequestContext,
 ) {
     let mut broker_client = get_broker_client().clone();
 
@@ -78,6 +80,7 @@ pub fn spawn_connection_manager_task(
                     loop_step_result = connection_manager_loop_step(
                         &mut broker_client,
                         &mut walreceiver_state,
+                        &ctx,
                     ) => match loop_step_result {
                         ControlFlow::Continue(()) => continue,
                         ControlFlow::Break(()) => {
@@ -101,6 +104,7 @@ pub fn spawn_connection_manager_task(
 async fn connection_manager_loop_step(
     broker_client: &mut BrokerClientChannel,
     walreceiver_state: &mut WalreceiverState,
+    ctx: &RequestContext,
 ) -> ControlFlow<(), ()> {
     let mut timeline_state_updates = walreceiver_state.timeline.subscribe_for_state_updates();
 
@@ -183,13 +187,23 @@ async fn connection_manager_loop_step(
 
             new_event = async {
                 loop {
+                    if walreceiver_state.timeline.current_state() == TimelineState::Loading {
+                        warn!("wal connection manager should only be launched after timeline has become active");
+                    }
                     match timeline_state_updates.changed().await {
                         Ok(()) => {
                             let new_state = walreceiver_state.timeline.current_state();
                             match new_state {
                                 // we're already active as walreceiver, no need to reactivate
                                 TimelineState::Active => continue,
-                                TimelineState::Broken | TimelineState::Stopping | TimelineState::Suspended => return ControlFlow::Continue(new_state),
+                                TimelineState::Broken | TimelineState::Stopping => {
+                                    info!("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);
+                                }
                             }
                         }
                         Err(_sender_dropped_error) => return ControlFlow::Break(()),
@@ -197,7 +211,7 @@ async fn connection_manager_loop_step(
                 }
             } => match new_event {
                 ControlFlow::Continue(new_state) => {
-                    info!("Timeline became inactive (new state: {new_state:?}), dropping current connections until it reactivates");
+                    info!("observed timeline state change, new state is {new_state:?}");
                     return ControlFlow::Continue(());
                 }
                 ControlFlow::Break(()) => {
@@ -226,6 +240,7 @@ async fn connection_manager_loop_step(
                 .change_connection(
                     new_candidate.safekeeper_id,
                     new_candidate.wal_source_connconf,
+                    ctx,
                 )
                 .await
         }
@@ -289,7 +304,9 @@ async fn subscribe_for_timeline_updates(
                 return resp.into_inner();
             }
             Err(e) => {
-                warn!("Attempt #{attempt}, failed to subscribe for timeline {id} updates in broker: {e:#}");
+                // Safekeeper nodes can stop pushing timeline updates to the broker, when no new writes happen and
+                // entire WAL is streamed. Keep this noticeable with logging, but do not warn/error.
+                info!("Attempt #{attempt}, failed to subscribe for timeline {id} updates in broker: {e:#}");
                 continue;
             }
         }
@@ -389,12 +406,17 @@ impl WalreceiverState {
         &mut self,
         new_sk_id: NodeId,
         new_wal_source_connconf: PgConnectionConfig,
+        ctx: &RequestContext,
     ) {
         self.drop_old_connection(true).await;
 
         let id = self.id;
         let connect_timeout = self.wal_connect_timeout;
         let timeline = Arc::clone(&self.timeline);
+        let ctx = ctx.detached_child(
+            TaskKind::WalReceiverConnectionHandler,
+            ctx.download_behavior(),
+        );
         let connection_handle = TaskHandle::spawn(move |events_sender, cancellation| {
             async move {
                 super::walreceiver_connection::handle_walreceiver_connection(
@@ -403,6 +425,7 @@ impl WalreceiverState {
                     events_sender,
                     cancellation,
                     connect_timeout,
+                    ctx,
                 )
                 .await
                 .context("walreceiver connection handling failure")
@@ -1233,18 +1256,18 @@ mod tests {
     const DUMMY_SAFEKEEPER_HOST: &str = "safekeeper_connstr";
 
     async fn dummy_state(harness: &TenantHarness<'_>) -> WalreceiverState {
+        let (tenant, ctx) = harness.load().await;
+        let timeline = tenant
+            .create_empty_timeline(TIMELINE_ID, Lsn(0), crate::DEFAULT_PG_VERSION, &ctx)
+            .expect("Failed to create an empty timeline for dummy wal connection manager");
+        let timeline = timeline.initialize(&ctx).unwrap();
+
         WalreceiverState {
             id: TenantTimelineId {
                 tenant_id: harness.tenant_id,
                 timeline_id: TIMELINE_ID,
             },
-            timeline: harness
-                .load()
-                .await
-                .create_empty_timeline(TIMELINE_ID, Lsn(0), crate::DEFAULT_PG_VERSION)
-                .expect("Failed to create an empty timeline for dummy wal connection manager")
-                .initialize()
-                .unwrap(),
+            timeline,
             wal_connect_timeout: Duration::from_secs(1),
             lagging_wal_timeout: Duration::from_secs(1),
             max_lsn_wal_lag: NonZeroU64::new(1024 * 1024).unwrap(),

pageserver/src/walreceiver/walreceiver_connection.rs

@@ -22,6 +22,7 @@ use tokio_postgres::{replication::ReplicationStream, Client};
 use tokio_util::sync::CancellationToken;
 use tracing::{debug, error, info, trace, warn};
 
+use crate::context::RequestContext;
 use crate::{metrics::LIVE_CONNECTIONS_COUNT, walreceiver::TaskStateUpdate};
 use crate::{
     task_mgr,
@@ -62,6 +63,7 @@ pub async fn handle_walreceiver_connection(
     events_sender: watch::Sender<TaskStateUpdate<WalConnectionStatus>>,
     cancellation: CancellationToken,
     connect_timeout: Duration,
+    ctx: RequestContext,
 ) -> anyhow::Result<()> {
     // Connect to the database in replication mode.
     info!("connecting to {wal_source_connconf:?}");
@@ -77,9 +79,13 @@ pub async fn handle_walreceiver_connection(
                 info!("DB connection stream finished: {expected_error}");
                 return Ok(());
             }
-            Err(elapsed) => anyhow::bail!(
-                "Timed out while waiting {elapsed} for walreceiver connection to open"
-            ),
+            Err(_) => {
+                // 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.
+                info!("Timed out while waiting {connect_timeout:?} for walreceiver connection to open");
+                return Ok(());
+            }
         }
     };
 
@@ -99,10 +105,14 @@ pub async fn handle_walreceiver_connection(
 
     // The connection object performs the actual communication with the database,
     // so spawn it off to run on its own.
+    let _connection_ctx = ctx.detached_child(
+        TaskKind::WalReceiverConnectionPoller,
+        ctx.download_behavior(),
+    );
     let connection_cancellation = cancellation.clone();
     task_mgr::spawn(
         WALRECEIVER_RUNTIME.handle(),
-        TaskKind::WalReceiverConnection,
+        TaskKind::WalReceiverConnectionPoller,
         Some(timeline.tenant_id),
         Some(timeline.timeline_id),
         "walreceiver connection",
@@ -117,7 +127,7 @@ pub async fn handle_walreceiver_connection(
                         }
                     }
                 },
-
+                // Future: replace connection_cancellation with connection_ctx cancellation
                 _ = connection_cancellation.cancelled() => info!("Connection cancelled"),
             }
             Ok(())
@@ -180,7 +190,7 @@ pub async fn handle_walreceiver_connection(
 
     let mut waldecoder = WalStreamDecoder::new(startpoint, timeline.pg_version);
 
-    let mut walingest = WalIngest::new(timeline.as_ref(), startpoint).await?;
+    let mut walingest = WalIngest::new(timeline.as_ref(), startpoint, &ctx).await?;
 
     while let Some(replication_message) = {
         select! {
@@ -251,7 +261,7 @@ pub async fn handle_walreceiver_connection(
                         ensure!(lsn.is_aligned());
 
                         walingest
-                            .ingest_record(recdata.clone(), lsn, &mut modification, &mut decoded)
+                            .ingest_record(recdata, lsn, &mut modification, &mut decoded, &ctx)
                             .await
                             .with_context(|| format!("could not ingest record at {lsn}"))?;
 
@@ -329,7 +339,7 @@ pub async fn handle_walreceiver_connection(
             // Send the replication feedback message.
             // Regular standby_status_update fields are put into this message.
             let (timeline_logical_size, _) = timeline
-                .get_current_logical_size()
+                .get_current_logical_size(&ctx)
                 .context("Status update creation failed to get current logical size")?;
             let status_update = ReplicationFeedback {
                 current_timeline_size: timeline_logical_size,