Move startup tracing context handling

compute_ctl: Break up main() into discrete phases
This commit is intentionally designed to have as small a diff as possible. To that end, the basic idea is that each distinct "chunk" of the previous main() has been wrapped in its own function, with the return values from each function being passed directly into the next. The structure of main() is now visible from its contents: 1. init() 2. process_cli() 3. wait_spec() 4. start_postgres() 5. wait_postgres() 6. cleanup_and_exit() There's a lot of other work that can / should(?) be done beyond this, but I figure that's more opinionated, and this should be a solid start.
2026-02-09 13:40:38 +00:00 · 2024-05-03 09:28:19 +03:00 · 2024-05-01 12:07:46 -07:00 · 2024-05-01 12:06:55 -07:00
203 changed files with 2937 additions and 8847 deletions
--- a/.config/nextest.toml
+++ b/.config/nextest.toml
@@ -1,2 +1,2 @@
 [profile.default]
-slow-timeout = { period = "60s", terminate-after = 3 }
+slow-timeout = { period = "20s", terminate-after = 3 }
--- a/.dockerignore
+++ b/.dockerignore
@@ -17,7 +17,6 @@
 !libs/
 !neon_local/
 !pageserver/
-!patches/
 !pgxn/
 !proxy/
 !s3_scrubber/
--- a/.github/actionlint.yml
+++ b/.github/actionlint.yml
@@ -1,9 +1,11 @@
 self-hosted-runner:
  labels:
    - arm64
+    - dev
    - gen3
    - large
-    - large-arm64
+    # Remove `macos-14` from the list after https://github.com/rhysd/actionlint/pull/392 is merged.
+    - macos-14
    - small
    - us-east-2
 config-variables:
--- a/.github/workflows/build-build-tools-image.yml
+++ b/.github/workflows/build-build-tools-image.yml
@@ -39,7 +39,7 @@ jobs:
      matrix:
        arch: [ x64, arm64 ]

-    runs-on: ${{ fromJson(format('["self-hosted", "gen3", "{0}"]', matrix.arch == 'arm64' && 'large-arm64' || 'large')) }}
+    runs-on: ${{ fromJson(format('["self-hosted", "dev", "{0}"]', matrix.arch)) }}

    env:
      IMAGE_TAG: ${{ inputs.image-tag }}
--- a/.github/workflows/build_and_test.yml
+++ b/.github/workflows/build_and_test.yml
@@ -236,6 +236,27 @@ jobs:
          submodules: true
          fetch-depth: 1

+      - name: Check Postgres submodules revision
+        shell: bash -euo pipefail {0}
+        run: |
+          # This is a temporary solution to ensure that the Postgres submodules revision is correct (i.e. the updated intentionally).
+          # Eventually it will be replaced by a regression test https://github.com/neondatabase/neon/pull/4603
+
+          FAILED=false
+          for postgres in postgres-v14 postgres-v15 postgres-v16; do
+            expected=$(cat vendor/revisions.json | jq --raw-output '."'"${postgres}"'"')
+            actual=$(git rev-parse "HEAD:vendor/${postgres}")
+            if [ "${expected}" != "${actual}" ]; then
+              echo >&2 "Expected ${postgres} rev to be at '${expected}', but it is at '${actual}'"
+              FAILED=true
+            fi
+          done
+
+          if [ "${FAILED}" = "true" ]; then
+            echo >&2 "Please update vendor/revisions.json if these changes are intentional"
+            exit 1
+          fi
+
      - name: Set pg 14 revision for caching
        id: pg_v14_rev
        run: echo pg_rev=$(git rev-parse HEAD:vendor/postgres-v14) >> $GITHUB_OUTPUT
@@ -341,9 +362,6 @@ jobs:
        env:
          NEXTEST_RETRIES: 3
        run: |
-          #nextest does not yet support running doctests
-          cargo test --doc $CARGO_FLAGS $CARGO_FEATURES
-
          for io_engine in std-fs tokio-epoll-uring ; do
            NEON_PAGESERVER_UNIT_TEST_VIRTUAL_FILE_IOENGINE=$io_engine ${cov_prefix} cargo nextest run $CARGO_FLAGS $CARGO_FEATURES
          done
--- a/.github/workflows/neon_extra_builds.yml
+++ b/.github/workflows/neon_extra_builds.yml
@@ -136,7 +136,7 @@ jobs:
  check-linux-arm-build:
    needs: [ check-permissions, build-build-tools-image ]
    timeout-minutes: 90
-    runs-on: [ self-hosted, large-arm64 ]
+    runs-on: [ self-hosted, dev, arm64 ]

    env:
      # Use release build only, to have less debug info around
@@ -232,20 +232,20 @@ jobs:

      - name: Run cargo build
        run: |
-          mold -run cargo build --locked $CARGO_FLAGS $CARGO_FEATURES --bins --tests -j$(nproc)
+          mold -run cargo build --locked $CARGO_FLAGS $CARGO_FEATURES --bins --tests

      - name: Run cargo test
        env:
          NEXTEST_RETRIES: 3
        run: |
-          cargo nextest run $CARGO_FEATURES -j$(nproc)
+          cargo nextest run $CARGO_FEATURES

          # Run separate tests for real S3
          export ENABLE_REAL_S3_REMOTE_STORAGE=nonempty
          export REMOTE_STORAGE_S3_BUCKET=neon-github-ci-tests
          export REMOTE_STORAGE_S3_REGION=eu-central-1
          # Avoid `$CARGO_FEATURES` since there's no `testing` feature in the e2e tests now
-          cargo nextest run --package remote_storage --test test_real_s3 -j$(nproc)
+          cargo nextest run --package remote_storage --test test_real_s3

          # Run separate tests for real Azure Blob Storage
          # XXX: replace region with `eu-central-1`-like region
@@ -255,12 +255,12 @@ jobs:
          export REMOTE_STORAGE_AZURE_CONTAINER="${{ vars.REMOTE_STORAGE_AZURE_CONTAINER }}"
          export REMOTE_STORAGE_AZURE_REGION="${{ vars.REMOTE_STORAGE_AZURE_REGION }}"
          # Avoid `$CARGO_FEATURES` since there's no `testing` feature in the e2e tests now
-          cargo nextest run --package remote_storage --test test_real_azure -j$(nproc)
+          cargo nextest run --package remote_storage --test test_real_azure

  check-codestyle-rust-arm:
    needs: [ check-permissions, build-build-tools-image ]
    timeout-minutes: 90
-    runs-on: [ self-hosted, large-arm64 ]
+    runs-on: [ self-hosted, dev, arm64 ]

    container:
      image: ${{ needs.build-build-tools-image.outputs.image }}
@@ -269,11 +269,6 @@ jobs:
        password: ${{ secrets.NEON_DOCKERHUB_PASSWORD }}
      options: --init

-    strategy:
-      fail-fast: false
-      matrix:
-        build_type: [ debug, release ]
-
    steps:
      - name: Fix git ownership
        run: |
@@ -310,35 +305,31 @@ jobs:
            exit 1
          fi
          echo "CLIPPY_COMMON_ARGS=${CLIPPY_COMMON_ARGS}" >> $GITHUB_ENV
-
      - name: Run cargo clippy (debug)
-        if: matrix.build_type == 'debug'
        run: cargo hack --feature-powerset clippy $CLIPPY_COMMON_ARGS
      - name: Run cargo clippy (release)
-        if: matrix.build_type == 'release'
        run: cargo hack --feature-powerset clippy --release $CLIPPY_COMMON_ARGS

      - name: Check documentation generation
-        if: matrix.build_type == 'release'
-        run: cargo doc --workspace --no-deps --document-private-items -j$(nproc)
+        run: cargo doc --workspace --no-deps --document-private-items
        env:
            RUSTDOCFLAGS: "-Dwarnings -Arustdoc::private_intra_doc_links"

      # Use `${{ !cancelled() }}` to run quck tests after the longer clippy run
      - name: Check formatting
-        if: ${{ !cancelled() && matrix.build_type == 'release' }}
+        if: ${{ !cancelled() }}
        run: cargo fmt --all -- --check

      # https://github.com/facebookincubator/cargo-guppy/tree/bec4e0eb29dcd1faac70b1b5360267fc02bf830e/tools/cargo-hakari#2-keep-the-workspace-hack-up-to-date-in-ci
      - name: Check rust dependencies
-        if: ${{ !cancelled() && matrix.build_type == 'release' }}
+        if: ${{ !cancelled() }}
        run: |
          cargo hakari generate --diff  # workspace-hack Cargo.toml is up-to-date
          cargo hakari manage-deps --dry-run  # all workspace crates depend on workspace-hack

      # https://github.com/EmbarkStudios/cargo-deny
      - name: Check rust licenses/bans/advisories/sources
-        if: ${{ !cancelled() && matrix.build_type == 'release' }}
+        if: ${{ !cancelled() }}
        run: cargo deny check

  gather-rust-build-stats:
@@ -347,7 +338,7 @@ jobs:
      contains(github.event.pull_request.labels.*.name, 'run-extra-build-stats') ||
      contains(github.event.pull_request.labels.*.name, 'run-extra-build-*') ||
      github.ref_name == 'main'
-    runs-on: [ self-hosted, large ]
+    runs-on: [ self-hosted, gen3, large ]
    container:
      image: ${{ needs.build-build-tools-image.outputs.image }}
      credentials:
@@ -378,7 +369,7 @@ jobs:
        run: make walproposer-lib -j$(nproc)

      - name: Produce the build stats
-        run: cargo build --all --release --timings -j$(nproc)
+        run: cargo build --all --release --timings

      - name: Upload the build stats
        id: upload-stats
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -25,9 +25,9 @@ checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"

 [[package]]
 name = "ahash"
-version = "0.8.11"
+version = "0.8.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e89da841a80418a9b391ebaea17f5c112ffaaa96f621d2c285b5174da76b9011"
+checksum = "d713b3834d76b85304d4d525563c1276e2e30dc97cc67bfb4585a4a29fc2c89f"
 dependencies = [
 "cfg-if",
 "const-random",
@@ -284,9 +284,9 @@ checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"

 [[package]]
 name = "aws-config"
-version = "1.3.0"
+version = "1.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "baaa0be6ee7d90b775ae6ccb6d2ba182b91219ec2001f92338773a094246af1d"
+checksum = "8b30c39ebe61f75d1b3785362b1586b41991873c9ab3e317a9181c246fb71d82"
 dependencies = [
 "aws-credential-types",
 "aws-runtime",
@@ -309,15 +309,14 @@ dependencies = [
 "time",
 "tokio",
 "tracing",
- "url",
 "zeroize",
 ]

 [[package]]
 name = "aws-credential-types"
-version = "1.2.0"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e16838e6c9e12125face1c1eff1343c75e3ff540de98ff7ebd61874a89bcfeb9"
+checksum = "fa8587ae17c8e967e4b05a62d495be2fb7701bec52a97f7acfe8a29f938384c8"
 dependencies = [
 "aws-smithy-async",
 "aws-smithy-runtime-api",
@@ -327,9 +326,9 @@ dependencies = [

 [[package]]
 name = "aws-runtime"
-version = "1.2.1"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "785da4a15e7b166b505fd577e4560c7a7cd8fbdf842eb1336cbcbf8944ce56f1"
+checksum = "b13dc54b4b49f8288532334bba8f87386a40571c47c37b1304979b556dc613c8"
 dependencies = [
 "aws-credential-types",
 "aws-sigv4",
@@ -374,11 +373,10 @@ dependencies = [

 [[package]]
 name = "aws-sdk-s3"
-version = "1.26.0"
+version = "1.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7bc5ce518d4b8d16e0408de7bdf1b3097cec61a7daa979750a208f8d9934386d"
+checksum = "951f7730f51a2155c711c85c79f337fbc02a577fa99d2a0a8059acfce5392113"
 dependencies = [
- "ahash",
 "aws-credential-types",
 "aws-runtime",
 "aws-sigv4",
@@ -393,25 +391,20 @@ dependencies = [
 "aws-smithy-xml",
 "aws-types",
 "bytes",
- "fastrand 2.0.0",
- "hex",
- "hmac",
 "http 0.2.9",
 "http-body 0.4.5",
- "lru",
 "once_cell",
 "percent-encoding",
 "regex-lite",
- "sha2",
 "tracing",
 "url",
 ]

 [[package]]
 name = "aws-sdk-sso"
-version = "1.22.0"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca3d6c4cba4e009391b72b0fcf12aff04ea3c9c3aa2ecaafa330326a8bd7e601"
+checksum = "f486420a66caad72635bc2ce0ff6581646e0d32df02aa39dc983bfe794955a5b"
 dependencies = [
 "aws-credential-types",
 "aws-runtime",
@@ -431,9 +424,9 @@ dependencies = [

 [[package]]
 name = "aws-sdk-ssooidc"
-version = "1.22.0"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "73400dc239d14f63d932f4ca7b55af5e9ef1f857f7d70655249ccc287adb2570"
+checksum = "39ddccf01d82fce9b4a15c8ae8608211ee7db8ed13a70b514bbfe41df3d24841"
 dependencies = [
 "aws-credential-types",
 "aws-runtime",
@@ -453,9 +446,9 @@ dependencies = [

 [[package]]
 name = "aws-sdk-sts"
-version = "1.22.0"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10f8858308af76fba3e5ffcf1bb56af5471574d2bdfaf0159470c25bc2f760e5"
+checksum = "1a591f8c7e6a621a501b2b5d2e88e1697fcb6274264523a6ad4d5959889a41ce"
 dependencies = [
 "aws-credential-types",
 "aws-runtime",
@@ -476,9 +469,9 @@ dependencies = [

 [[package]]
 name = "aws-sigv4"
-version = "1.2.1"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "58b56f1cbe6fd4d0c2573df72868f20ab1c125ca9c9dbce17927a463433a2e57"
+checksum = "11d6f29688a4be9895c0ba8bef861ad0c0dac5c15e9618b9b7a6c233990fc263"
 dependencies = [
 "aws-credential-types",
 "aws-smithy-eventstream",
@@ -505,9 +498,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-async"
-version = "1.2.1"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62220bc6e97f946ddd51b5f1361f78996e704677afc518a4ff66b7a72ea1378c"
+checksum = "d26ea8fa03025b2face2b3038a63525a10891e3d8829901d502e5384a0d8cd46"
 dependencies = [
 "futures-util",
 "pin-project-lite",
@@ -516,9 +509,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-checksums"
-version = "0.60.7"
+version = "0.60.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fa43bc04a6b2441968faeab56e68da3812f978a670a5db32accbdcafddd12f"
+checksum = "be2acd1b9c6ae5859999250ed5a62423aedc5cf69045b844432de15fa2f31f2b"
 dependencies = [
 "aws-smithy-http",
 "aws-smithy-types",
@@ -548,9 +541,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-http"
-version = "0.60.8"
+version = "0.60.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a7de001a1b9a25601016d8057ea16e31a45fdca3751304c8edf4ad72e706c08"
+checksum = "3f10fa66956f01540051b0aa7ad54574640f748f9839e843442d99b970d3aff9"
 dependencies = [
 "aws-smithy-eventstream",
 "aws-smithy-runtime-api",
@@ -588,9 +581,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-runtime"
-version = "1.5.0"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9ac79e9f3a4d576f3cd4a470a0275b138d9e7b11b1cd514a6858ae0a79dd5bb"
+checksum = "ec81002d883e5a7fd2bb063d6fb51c4999eb55d404f4fff3dd878bf4733b9f01"
 dependencies = [
 "aws-smithy-async",
 "aws-smithy-http",
@@ -601,9 +594,8 @@ dependencies = [
 "h2 0.3.26",
 "http 0.2.9",
 "http-body 0.4.5",
- "http-body 1.0.0",
 "hyper 0.14.26",
- "hyper-rustls 0.24.0",
+ "hyper-rustls",
 "once_cell",
 "pin-project-lite",
 "pin-utils",
@@ -614,9 +606,9 @@ dependencies = [

 [[package]]
 name = "aws-smithy-runtime-api"
-version = "1.6.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04ec42c2f5c0e7796a2848dde4d9f3bf8ce12ccbb3d5aa40c52fa0cdd61a1c47"
+checksum = "9acb931e0adaf5132de878f1398d83f8677f90ba70f01f65ff87f6d7244be1c5"
 dependencies = [
 "aws-smithy-async",
 "aws-smithy-types",
@@ -631,19 +623,16 @@ dependencies = [

 [[package]]
 name = "aws-smithy-types"
-version = "1.1.9"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "baf98d97bba6ddaba180f1b1147e202d8fe04940403a95a3f826c790f931bbd1"
+checksum = "abe14dceea1e70101d38fbf2a99e6a34159477c0fb95e68e05c66bd7ae4c3729"
 dependencies = [
 "base64-simd",
 "bytes",
 "bytes-utils",
 "futures-core",
 "http 0.2.9",
- "http 1.1.0",
 "http-body 0.4.5",
- "http-body 1.0.0",
- "http-body-util",
 "itoa",
 "num-integer",
 "pin-project-lite",
@@ -657,18 +646,18 @@ dependencies = [

 [[package]]
 name = "aws-smithy-xml"
-version = "0.60.8"
+version = "0.60.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d123fbc2a4adc3c301652ba8e149bf4bc1d1725affb9784eb20c953ace06bf55"
+checksum = "872c68cf019c0e4afc5de7753c4f7288ce4b71663212771bf5e4542eb9346ca9"
 dependencies = [
 "xmlparser",
 ]

 [[package]]
 name = "aws-types"
-version = "1.2.0"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a43b56df2c529fe44cb4d92bd64d0479883fb9608ff62daede4df5405381814"
+checksum = "0dbf2f3da841a8930f159163175cf6a3d16ddde517c1b0fba7aa776822800f40"
 dependencies = [
 "aws-credential-types",
 "aws-smithy-async",
@@ -695,7 +684,7 @@ dependencies = [
 "http-body 0.4.5",
 "hyper 0.14.26",
 "itoa",
- "matchit 0.7.0",
+ "matchit",
 "memchr",
 "mime",
 "percent-encoding",
@@ -751,7 +740,7 @@ dependencies = [
 "pin-project",
 "quick-xml",
 "rand 0.8.5",
- "reqwest 0.11.19",
+ "reqwest",
 "rustc_version",
 "serde",
 "serde_json",
@@ -876,12 +865,6 @@ version = "0.21.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f1e31e207a6b8fb791a38ea3105e6cb541f55e4d029902d3039a4ad07cc4105"

-[[package]]
-name = "base64"
-version = "0.22.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72b3254f16251a8381aa12e40e3c4d2f0199f8c6508fbecb9d91f575e0fbb8c6"
-
 [[package]]
 name = "base64-simd"
 version = "0.8.0"
@@ -1227,7 +1210,7 @@ dependencies = [
 "postgres",
 "regex",
 "remote_storage",
- "reqwest 0.12.4",
+ "reqwest",
 "rust-ini",
 "serde",
 "serde_json",
@@ -1346,7 +1329,7 @@ dependencies = [
 "postgres_backend",
 "postgres_connection",
 "regex",
- "reqwest 0.12.4",
+ "reqwest",
 "safekeeper_api",
 "scopeguard",
 "serde",
@@ -1359,7 +1342,6 @@ dependencies = [
 "tokio-postgres",
 "tokio-util",
 "toml",
- "toml_edit",
 "tracing",
 "url",
 "utils",
@@ -2381,17 +2363,6 @@ dependencies = [
 "winapi",
 ]

-[[package]]
-name = "hostname"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f9c7c7c8ac16c798734b8a24560c1362120597c40d5e1459f09498f8f6c8f2ba"
-dependencies = [
- "cfg-if",
- "libc",
- "windows 0.52.0",
-]
-
 [[package]]
 name = "http"
 version = "0.2.9"
@@ -2538,7 +2509,6 @@ dependencies = [
 "pin-project-lite",
 "smallvec",
 "tokio",
- "want",
 ]

 [[package]]
@@ -2556,23 +2526,6 @@ dependencies = [
 "tokio-rustls 0.24.0",
 ]

-[[package]]
-name = "hyper-rustls"
-version = "0.26.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a0bea761b46ae2b24eb4aef630d8d1c398157b6fc29e6350ecf090a0b70c952c"
-dependencies = [
- "futures-util",
- "http 1.1.0",
- "hyper 1.2.0",
- "hyper-util",
- "rustls 0.22.4",
- "rustls-pki-types",
- "tokio",
- "tokio-rustls 0.25.0",
- "tower-service",
-]
-
 [[package]]
 name = "hyper-timeout"
 version = "0.4.1"
@@ -2620,7 +2573,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ca38ef113da30126bbff9cd1705f9273e15d45498615d138b0c20279ac7a76aa"
 dependencies = [
 "bytes",
- "futures-channel",
 "futures-util",
 "http 1.1.0",
 "http-body 1.0.0",
@@ -2628,9 +2580,6 @@ dependencies = [
 "pin-project-lite",
 "socket2 0.5.5",
 "tokio",
- "tower",
- "tower-service",
- "tracing",
 ]

 [[package]]
@@ -2644,7 +2593,7 @@ dependencies = [
 "iana-time-zone-haiku",
 "js-sys",
 "wasm-bindgen",
- "windows 0.48.0",
+ "windows",
 ]

 [[package]]
@@ -2946,15 +2895,6 @@ version = "0.4.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5e6163cb8c49088c2c36f57875e58ccd8c87c7427f7fbd50ea6710b2f3f2e8f"

-[[package]]
-name = "lru"
-version = "0.12.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d3262e75e648fce39813cb56ac41f3c3e3f65217ebf3844d818d1f9398cfb0dc"
-dependencies = [
- "hashbrown 0.14.0",
-]
-
 [[package]]
 name = "match_cfg"
 version = "0.1.0"
@@ -2976,12 +2916,6 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b87248edafb776e59e6ee64a79086f65890d3510f2c656c000bf2a7e8a0aea40"

-[[package]]
-name = "matchit"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "540f1c43aed89909c0cc0cc604e3bb2f7e7a341a3728a9e6cfe760e733cd11ed"
-
 [[package]]
 name = "md-5"
 version = "0.10.5"
@@ -3115,6 +3049,16 @@ version = "0.3.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6877bb514081ee2a7ff5ef9de3281f14a4dd4bceac4c09388074a6b5df8a139a"

+[[package]]
+name = "mime_guess"
+version = "2.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4192263c238a5f0d0c6bfd21f336a313a4ce1c450542449ca191bb657b4642ef"
+dependencies = [
+ "mime",
+ "unicase",
+]
+
 [[package]]
 name = "minimal-lexical"
 version = "0.2.1"
@@ -3458,7 +3402,7 @@ dependencies = [
 "bytes",
 "http 0.2.9",
 "opentelemetry_api",
- "reqwest 0.11.19",
+ "reqwest",
 ]

 [[package]]
@@ -3476,7 +3420,7 @@ dependencies = [
 "opentelemetry_api",
 "opentelemetry_sdk",
 "prost",
- "reqwest 0.11.19",
+ "reqwest",
 "thiserror",
 "tokio",
 "tonic",
@@ -3705,7 +3649,7 @@ dependencies = [
 "rand 0.8.5",
 "regex",
 "remote_storage",
- "reqwest 0.12.4",
+ "reqwest",
 "rpds",
 "scopeguard",
 "serde",
@@ -3775,7 +3719,7 @@ dependencies = [
 "futures",
 "pageserver_api",
 "postgres",
- "reqwest 0.12.4",
+ "reqwest",
 "serde",
 "thiserror",
 "tokio",
@@ -4384,7 +4328,7 @@ dependencies = [
 "hashlink",
 "hex",
 "hmac",
- "hostname 0.3.1",
+ "hostname",
 "http 1.1.0",
 "http-body-util",
 "humantime",
@@ -4392,7 +4336,6 @@ dependencies = [
 "hyper 1.2.0",
 "hyper-tungstenite",
 "hyper-util",
- "indexmap 2.0.1",
 "ipnet",
 "itertools",
 "lasso",
@@ -4418,7 +4361,7 @@ dependencies = [
 "redis",
 "regex",
 "remote_storage",
- "reqwest 0.12.4",
+ "reqwest",
 "reqwest-middleware",
 "reqwest-retry",
 "reqwest-tracing",
@@ -4445,7 +4388,6 @@ dependencies = [
 "tokio-postgres-rustls",
 "tokio-rustls 0.25.0",
 "tokio-util",
- "tower-service",
 "tracing",
 "tracing-opentelemetry",
 "tracing-subscriber",
@@ -4736,7 +4678,6 @@ dependencies = [
 "scopeguard",
 "serde",
 "serde_json",
- "sync_wrapper",
 "test-context",
 "tokio",
 "tokio-stream",
@@ -4762,106 +4703,69 @@ dependencies = [
 "http 0.2.9",
 "http-body 0.4.5",
 "hyper 0.14.26",
+ "hyper-rustls",
 "hyper-tls",
 "ipnet",
 "js-sys",
 "log",
 "mime",
+ "mime_guess",
 "native-tls",
 "once_cell",
 "percent-encoding",
 "pin-project-lite",
+ "rustls 0.21.11",
+ "rustls-pemfile 1.0.2",
 "serde",
 "serde_json",
 "serde_urlencoded",
 "tokio",
 "tokio-native-tls",
+ "tokio-rustls 0.24.0",
 "tokio-util",
 "tower-service",
 "url",
 "wasm-bindgen",
 "wasm-bindgen-futures",
- "wasm-streams 0.3.0",
+ "wasm-streams",
 "web-sys",
- "winreg 0.50.0",
-]
-
-[[package]]
-name = "reqwest"
-version = "0.12.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "566cafdd92868e0939d3fb961bd0dc25fcfaaed179291093b3d43e6b3150ea10"
-dependencies = [
- "base64 0.22.1",
- "bytes",
- "futures-channel",
- "futures-core",
- "futures-util",
- "http 1.1.0",
- "http-body 1.0.0",
- "http-body-util",
- "hyper 1.2.0",
- "hyper-rustls 0.26.0",
- "hyper-util",
- "ipnet",
- "js-sys",
- "log",
- "mime",
- "once_cell",
- "percent-encoding",
- "pin-project-lite",
- "rustls 0.22.4",
- "rustls-pemfile 2.1.1",
- "rustls-pki-types",
- "serde",
- "serde_json",
- "serde_urlencoded",
- "sync_wrapper",
- "tokio",
- "tokio-rustls 0.25.0",
- "tokio-util",
- "tower-service",
- "url",
- "wasm-bindgen",
- "wasm-bindgen-futures",
- "wasm-streams 0.4.0",
- "web-sys",
- "webpki-roots 0.26.1",
- "winreg 0.52.0",
+ "webpki-roots 0.25.2",
+ "winreg",
 ]

 [[package]]
 name = "reqwest-middleware"
-version = "0.3.0"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0209efb52486ad88136190094ee214759ef7507068b27992256ed6610eb71a01"
+checksum = "4531c89d50effe1fac90d095c8b133c20c5c714204feee0bfc3fd158e784209d"
 dependencies = [
 "anyhow",
 "async-trait",
- "http 1.1.0",
- "reqwest 0.12.4",
+ "http 0.2.9",
+ "reqwest",
 "serde",
+ "task-local-extensions",
 "thiserror",
- "tower-service",
 ]

 [[package]]
 name = "reqwest-retry"
-version = "0.5.0"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "40f342894422862af74c50e1e9601cf0931accc9c6981e5eb413c46603b616b5"
+checksum = "48d0fd6ef4c6d23790399fe15efc8d12cd9f3d4133958f9bd7801ee5cbaec6c4"
 dependencies = [
 "anyhow",
 "async-trait",
 "chrono",
 "futures",
 "getrandom 0.2.11",
- "http 1.1.0",
- "hyper 1.2.0",
+ "http 0.2.9",
+ "hyper 0.14.26",
 "parking_lot 0.11.2",
- "reqwest 0.12.4",
+ "reqwest",
 "reqwest-middleware",
 "retry-policies",
+ "task-local-extensions",
 "tokio",
 "tracing",
 "wasm-timer",
@@ -4869,27 +4773,27 @@ dependencies = [

 [[package]]
 name = "reqwest-tracing"
-version = "0.5.0"
+version = "0.4.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b253954a1979e02eabccd7e9c3d61d8f86576108baa160775e7f160bb4e800a3"
+checksum = "5a0152176687dd5cfe7f507ac1cb1a491c679cfe483afd133a7db7aaea818bb3"
 dependencies = [
 "anyhow",
 "async-trait",
 "getrandom 0.2.11",
- "http 1.1.0",
- "matchit 0.8.2",
+ "matchit",
 "opentelemetry",
- "reqwest 0.12.4",
+ "reqwest",
 "reqwest-middleware",
+ "task-local-extensions",
 "tracing",
 "tracing-opentelemetry",
 ]

 [[package]]
 name = "retry-policies"
-version = "0.3.0"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "493b4243e32d6eedd29f9a398896e35c6943a123b55eec97dcaee98310d25810"
+checksum = "e09bbcb5003282bcb688f0bae741b278e9c7e8f378f561522c9806c58e075d9b"
 dependencies = [
 "anyhow",
 "chrono",
@@ -5215,7 +5119,7 @@ dependencies = [
 "postgres_ffi",
 "rand 0.8.5",
 "remote_storage",
- "reqwest 0.12.4",
+ "reqwest",
 "serde",
 "serde_json",
 "serde_with",
@@ -5266,7 +5170,7 @@ dependencies = [
 "rand 0.8.5",
 "regex",
 "remote_storage",
- "reqwest 0.12.4",
+ "reqwest",
 "safekeeper_api",
 "scopeguard",
 "sd-notify",
@@ -5396,12 +5300,12 @@ checksum = "bebd363326d05ec3e2f532ab7660680f3b02130d780c299bca73469d521bc0ed"

 [[package]]
 name = "sentry"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "00421ed8fa0c995f07cde48ba6c89e80f2b312f74ff637326f392fbfd23abe02"
+checksum = "2e95efd0cefa32028cdb9766c96de71d96671072f9fb494dc9fb84c0ef93e52b"
 dependencies = [
 "httpdate",
- "reqwest 0.12.4",
+ "reqwest",
 "rustls 0.21.11",
 "sentry-backtrace",
 "sentry-contexts",
@@ -5415,9 +5319,9 @@ dependencies = [

 [[package]]
 name = "sentry-backtrace"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a79194074f34b0cbe5dd33896e5928bbc6ab63a889bd9df2264af5acb186921e"
+checksum = "6ac2bac6f310c4c4c4bb094d1541d32ae497f8c5c23405e85492cefdfe0971a9"
 dependencies = [
 "backtrace",
 "once_cell",
@@ -5427,11 +5331,11 @@ dependencies = [

 [[package]]
 name = "sentry-contexts"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eba8870c5dba2bfd9db25c75574a11429f6b95957b0a78ac02e2970dd7a5249a"
+checksum = "6c3e17295cecdbacf66c5bd38d6e1147e09e1e9d824d2d5341f76638eda02a3a"
 dependencies = [
- "hostname 0.4.0",
+ "hostname",
 "libc",
 "os_info",
 "rustc_version",
@@ -5441,9 +5345,9 @@ dependencies = [

 [[package]]
 name = "sentry-core"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "46a75011ea1c0d5c46e9e57df03ce81f5c7f0a9e199086334a1f9c0a541e0826"
+checksum = "8339474f587f36cb110fa1ed1b64229eea6d47b0b886375579297b7e47aeb055"
 dependencies = [
 "once_cell",
 "rand 0.8.5",
@@ -5454,9 +5358,9 @@ dependencies = [

 [[package]]
 name = "sentry-panic"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2eaa3ecfa3c8750c78dcfd4637cfa2598b95b52897ed184b4dc77fcf7d95060d"
+checksum = "875b69f506da75bd664029eafb05f8934297d2990192896d17325f066bd665b7"
 dependencies = [
 "sentry-backtrace",
 "sentry-core",
@@ -5464,9 +5368,9 @@ dependencies = [

 [[package]]
 name = "sentry-tracing"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f715932bf369a61b7256687c6f0554141b7ce097287e30e3f7ed6e9de82498fe"
+checksum = "89feead9bdd116f8035e89567651340fc382db29240b6c55ef412078b08d1aa3"
 dependencies = [
 "sentry-backtrace",
 "sentry-core",
@@ -5476,13 +5380,13 @@ dependencies = [

 [[package]]
 name = "sentry-types"
-version = "0.32.3"
+version = "0.31.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4519c900ce734f7a0eb7aba0869dfb225a7af8820634a7dd51449e3b093cfb7c"
+checksum = "99dc599bd6646884fc403d593cdcb9816dd67c50cff3271c01ff123617908dcd"
 dependencies = [
 "debugid",
+ "getrandom 0.2.11",
 "hex",
- "rand 0.8.5",
 "serde",
 "serde_json",
 "thiserror",
@@ -5874,12 +5778,10 @@ dependencies = [
 "pageserver_client",
 "postgres_connection",
 "r2d2",
- "reqwest 0.12.4",
+ "reqwest",
 "routerify",
 "serde",
 "serde_json",
- "strum",
- "strum_macros",
 "thiserror",
 "tokio",
 "tokio-util",
@@ -5898,7 +5800,7 @@ dependencies = [
 "hyper 0.14.26",
 "pageserver_api",
 "pageserver_client",
- "reqwest 0.12.4",
+ "reqwest",
 "serde",
 "serde_json",
 "thiserror",
@@ -5952,7 +5854,7 @@ checksum = "81cdd64d312baedb58e21336b31bc043b77e01cc99033ce76ef539f78e965ebc"
 [[package]]
 name = "svg_fmt"
 version = "0.4.2"
-source = "git+https://github.com/neondatabase/fork--nical--rust_debug?branch=neon#c1820b28664b5df68de7f043fccf2ed5d67b6ae8"
+source = "git+https://github.com/neondatabase/fork--nical--rust_debug?branch=neon#b9501105e746629004bc6d0473639320939dbe10"

 [[package]]
 name = "syn"
@@ -5981,9 +5883,6 @@ name = "sync_wrapper"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2047c6ded9c721764247e62cd3b03c09ffc529b2ba5b10ec482ae507a4a70160"
-dependencies = [
- "futures-core",
-]

 [[package]]
 name = "synstructure"
@@ -6536,11 +6435,10 @@ dependencies = [

 [[package]]
 name = "tracing"
-version = "0.1.37"
+version = "0.1.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8ce8c33a8d48bd45d624a6e523445fd21ec13d3653cd51f681abf67418f54eb8"
+checksum = "c3523ab5a71916ccf420eebdf5521fcef02141234bbc0b8a49f2fdc4544364ef"
 dependencies = [
- "cfg-if",
 "log",
 "pin-project-lite",
 "tracing-attributes",
@@ -6560,9 +6458,9 @@ dependencies = [

 [[package]]
 name = "tracing-attributes"
-version = "0.1.24"
+version = "0.1.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f57e3ca2a01450b1a921183a9c9cbfda207fd822cef4ccb00a65402cbba7a74"
+checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
 dependencies = [
 "proc-macro2",
 "quote",
@@ -6571,9 +6469,9 @@ dependencies = [

 [[package]]
 name = "tracing-core"
-version = "0.1.31"
+version = "0.1.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0955b8137a1df6f1a2e9a37d8a6656291ff0297c1a97c24e0d8425fe2312f79a"
+checksum = "c06d3da6113f116aaee68e4d601191614c9053067f9ab7f6edbcb161237daa54"
 dependencies = [
 "once_cell",
 "valuable",
@@ -6602,14 +6500,12 @@ dependencies = [

 [[package]]
 name = "tracing-opentelemetry"
-version = "0.21.0"
+version = "0.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "75327c6b667828ddc28f5e3f169036cb793c3f588d83bf0f262a7f062ffed3c8"
+checksum = "fc09e402904a5261e42cf27aea09ccb7d5318c6717a9eec3d8e2e65c56b18f19"
 dependencies = [
 "once_cell",
 "opentelemetry",
- "opentelemetry_sdk",
- "smallvec",
 "tracing",
 "tracing-core",
 "tracing-log",
@@ -6655,7 +6551,7 @@ dependencies = [
 "opentelemetry",
 "opentelemetry-otlp",
 "opentelemetry-semantic-conventions",
- "reqwest 0.12.4",
+ "reqwest",
 "tokio",
 "tracing",
 "tracing-opentelemetry",
@@ -6741,6 +6637,15 @@ dependencies = [
 "libc",
 ]

+[[package]]
+name = "unicase"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50f37be617794602aabbeee0be4f259dc1778fabe05e2d67ee8f79326d5cb4f6"
+dependencies = [
+ "version_check",
+]
+
 [[package]]
 name = "unicode-bidi"
 version = "0.3.13"
@@ -7099,19 +7004,6 @@ dependencies = [
 "web-sys",
 ]

-[[package]]
-name = "wasm-streams"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b65dc4c90b63b118468cf747d8bf3566c1913ef60be765b5730ead9e0a3ba129"
-dependencies = [
- "futures-util",
- "js-sys",
- "wasm-bindgen",
- "wasm-bindgen-futures",
- "web-sys",
-]
-
 [[package]]
 name = "wasm-timer"
 version = "0.2.5"
@@ -7152,15 +7044,6 @@ version = "0.25.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14247bb57be4f377dfb94c72830b8ce8fc6beac03cf4bf7b9732eadd414123fc"

-[[package]]
-name = "webpki-roots"
-version = "0.26.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b3de34ae270483955a94f4b21bdaaeb83d508bb84a01435f393818edb0012009"
-dependencies = [
- "rustls-pki-types",
-]
-
 [[package]]
 name = "which"
 version = "4.4.0"
@@ -7212,25 +7095,6 @@ dependencies = [
 "windows-targets 0.48.0",
 ]

-[[package]]
-name = "windows"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e48a53791691ab099e5e2ad123536d0fff50652600abaf43bbf952894110d0be"
-dependencies = [
- "windows-core",
- "windows-targets 0.52.4",
-]
-
-[[package]]
-name = "windows-core"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "33ab640c8d7e35bf8ba19b884ba838ceb4fba93a4e8c65a9059d08afcfc683d9"
-dependencies = [
- "windows-targets 0.52.4",
-]
-
 [[package]]
 name = "windows-sys"
 version = "0.42.0"
@@ -7463,16 +7327,6 @@ dependencies = [
 "windows-sys 0.48.0",
 ]

-[[package]]
-name = "winreg"
-version = "0.52.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a277a57398d4bfa075df44f501a17cfdf8542d224f0d36095a2adc7aee4ef0a5"
-dependencies = [
- "cfg-if",
- "windows-sys 0.48.0",
-]
-
 [[package]]
 name = "workspace_hack"
 version = "0.1.0"
@@ -7522,8 +7376,7 @@ dependencies = [
 "regex",
 "regex-automata 0.4.3",
 "regex-syntax 0.8.2",
- "reqwest 0.11.19",
- "reqwest 0.12.4",
+ "reqwest",
 "rustls 0.21.11",
 "scopeguard",
 "serde",
@@ -7533,7 +7386,6 @@ dependencies = [
 "subtle",
 "syn 1.0.109",
 "syn 2.0.52",
- "sync_wrapper",
 "time",
 "time-macros",
 "tokio",
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -52,14 +52,14 @@ azure_storage_blobs = "0.19"
 flate2 = "1.0.26"
 async-stream = "0.3"
 async-trait = "0.1"
-aws-config = { version = "1.3", default-features = false, features=["rustls"] }
-aws-sdk-s3 = "1.26"
+aws-config = { version = "1.1.4", default-features = false, features=["rustls"] }
+aws-sdk-s3 = "1.14"
 aws-sdk-iam = "1.15.0"
-aws-smithy-async = { version = "1.2.1", default-features = false, features=["rt-tokio"] }
-aws-smithy-types = "1.1.9"
-aws-credential-types = "1.2.0"
-aws-sigv4 = { version = "1.2.1", features = ["sign-http"] }
-aws-types = "1.2.0"
+aws-smithy-async = { version = "1.1.4", default-features = false, features=["rt-tokio"] }
+aws-smithy-types = "1.1.4"
+aws-credential-types = "1.1.4"
+aws-sigv4 = { version = "1.2.0", features = ["sign-http"] }
+aws-types = "1.1.7"
 axum = { version = "0.6.20", features = ["ws"] }
 base64 = "0.13.0"
 bincode = "1.3"
@@ -99,7 +99,6 @@ humantime = "2.1"
 humantime-serde = "1.1.1"
 hyper = "0.14"
 hyper-tungstenite = "0.13.0"
-indexmap = "2"
 inotify = "0.10.2"
 ipnet = "2.9.0"
 itertools = "0.10"
@@ -131,10 +130,10 @@ prost = "0.11"
 rand = "0.8"
 redis = { version = "0.25.2", features = ["tokio-rustls-comp", "keep-alive"] }
 regex = "1.10.2"
-reqwest = { version = "0.12", default-features = false, features = ["rustls-tls"] }
-reqwest-tracing = { version = "0.5", features = ["opentelemetry_0_20"] }
-reqwest-middleware = "0.3.0"
-reqwest-retry = "0.5"
+reqwest = { version = "0.11", default-features = false, features = ["rustls-tls"] }
+reqwest-tracing = { version = "0.4.7", features = ["opentelemetry_0_20"] }
+reqwest-middleware = "0.2.0"
+reqwest-retry = "0.2.2"
 routerify = "3"
 rpds = "0.13"
 rustc-hash = "1.1.0"
@@ -144,7 +143,7 @@ rustls-split = "0.3"
 scopeguard = "1.1"
 sysinfo = "0.29.2"
 sd-notify = "0.4.1"
-sentry = { version = "0.32", default-features = false, features = ["backtrace", "contexts", "panic", "rustls", "reqwest" ] }
+sentry = { version = "0.31", default-features = false, features = ["backtrace", "contexts", "panic", "rustls", "reqwest" ] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1"
 serde_path_to_error = "0.1"
@@ -178,10 +177,9 @@ tokio-util = { version = "0.7.10", features = ["io", "rt"] }
 toml = "0.7"
 toml_edit = "0.19"
 tonic = {version = "0.9", features = ["tls", "tls-roots"]}
-tower-service = "0.3.2"
 tracing = "0.1"
 tracing-error = "0.2.0"
-tracing-opentelemetry = "0.21.0"
+tracing-opentelemetry = "0.20.0"
 tracing-subscriber = { version = "0.3", default_features = false, features = ["smallvec", "fmt", "tracing-log", "std", "env-filter", "json", "ansi"] }
 twox-hash = { version = "1.6.3", default-features = false }
 url = "2.2"
--- a/Dockerfile.build-tools
+++ b/Dockerfile.build-tools
@@ -65,7 +65,7 @@ RUN curl -sL "https://github.com/peak/s5cmd/releases/download/v${S5CMD_VERSION}/
    && mv s5cmd /usr/local/bin/s5cmd

 # LLVM
-ENV LLVM_VERSION=18
+ENV LLVM_VERSION=17
 RUN curl -fsSL 'https://apt.llvm.org/llvm-snapshot.gpg.key' | apt-key add - \
    && echo "deb http://apt.llvm.org/bullseye/ llvm-toolchain-bullseye-${LLVM_VERSION} main" > /etc/apt/sources.list.d/llvm.stable.list \
    && apt update \
@@ -141,7 +141,7 @@ WORKDIR /home/nonroot

 # Rust
 # Please keep the version of llvm (installed above) in sync with rust llvm (`rustc --version --verbose | grep LLVM`)
-ENV RUSTC_VERSION=1.78.0
+ENV RUSTC_VERSION=1.77.0
 ENV RUSTUP_HOME="/home/nonroot/.rustup"
 ENV PATH="/home/nonroot/.cargo/bin:${PATH}"
 RUN curl -sSO https://static.rust-lang.org/rustup/dist/$(uname -m)-unknown-linux-gnu/rustup-init && whoami && \
--- a/Dockerfile.compute-node
+++ b/Dockerfile.compute-node
@@ -241,12 +241,9 @@ RUN wget https://github.com/df7cb/postgresql-unit/archive/refs/tags/7.7.tar.gz -
 FROM build-deps AS vector-pg-build
 COPY --from=pg-build /usr/local/pgsql/ /usr/local/pgsql/

-COPY patches/pgvector.patch /pgvector.patch
-
-RUN wget https://github.com/pgvector/pgvector/archive/refs/tags/v0.6.0.tar.gz -O pgvector.tar.gz && \
-    echo "b0cf4ba1ab016335ac8fb1cada0d2106235889a194fffeece217c5bda90b2f19 pgvector.tar.gz" | sha256sum --check && \
+RUN wget https://github.com/pgvector/pgvector/archive/refs/tags/v0.5.1.tar.gz -O pgvector.tar.gz && \
+    echo "cc7a8e034a96e30a819911ac79d32f6bc47bdd1aa2de4d7d4904e26b83209dc8 pgvector.tar.gz" | sha256sum --check && \
    mkdir pgvector-src && cd pgvector-src && tar xvzf ../pgvector.tar.gz --strip-components=1 -C . && \
-    patch -p1 < /pgvector.patch && \
    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 && \
    echo 'trusted = true' >> /usr/local/pgsql/share/extension/vector.control
--- a/11
+++ b/11
@@ -81,14 +81,11 @@ $(POSTGRES_INSTALL_DIR)/build/%/config.status:
 		echo "'git submodule update --init --recursive --depth 2 --progress .' in project root.\n"; \
 		exit 1; }
 	mkdir -p $(POSTGRES_INSTALL_DIR)/build/$*
-
-	VERSION=$*; \
-	EXTRA_VERSION=$$(cd $(ROOT_PROJECT_DIR)/vendor/postgres-$$VERSION && git rev-parse HEAD); \
-	(cd $(POSTGRES_INSTALL_DIR)/build/$$VERSION && \
-	env PATH="$(EXTRA_PATH_OVERRIDES):$$PATH" $(ROOT_PROJECT_DIR)/vendor/postgres-$$VERSION/configure \
+	(cd $(POSTGRES_INSTALL_DIR)/build/$* && \
+	env PATH="$(EXTRA_PATH_OVERRIDES):$$PATH" $(ROOT_PROJECT_DIR)/vendor/postgres-$*/configure \
 		CFLAGS='$(PG_CFLAGS)' \
-		$(PG_CONFIGURE_OPTS) --with-extra-version=" ($$EXTRA_VERSION)" \
-		--prefix=$(abspath $(POSTGRES_INSTALL_DIR))/$$VERSION > configure.log)
+		$(PG_CONFIGURE_OPTS) \
+		--prefix=$(abspath $(POSTGRES_INSTALL_DIR))/$* > configure.log)

 # nicer alias to run 'configure'
 # Note: I've been unable to use templates for this part of our configuration.
--- a/compute_tools/src/bin/compute_ctl.rs
+++ b/compute_tools/src/bin/compute_ctl.rs
@@ -47,7 +47,7 @@ use chrono::Utc;
 use clap::Arg;
 use signal_hook::consts::{SIGQUIT, SIGTERM};
 use signal_hook::{consts::SIGINT, iterator::Signals};
-use tracing::{error, info, warn};
+use tracing::{error, info};
 use url::Url;

 use compute_api::responses::ComputeStatus;
@@ -63,7 +63,6 @@ use compute_tools::logger::*;
 use compute_tools::monitor::launch_monitor;
 use compute_tools::params::*;
 use compute_tools::spec::*;
-use compute_tools::swap::resize_swap;

 // this is an arbitrary build tag. Fine as a default / for testing purposes
 // in-case of not-set environment var
@@ -72,29 +71,24 @@ const BUILD_TAG_DEFAULT: &str = "latest";
 fn main() -> Result<()> {
    let (build_tag, clap_args) = init()?;

-    let (pg_handle, start_pg_result) = {
+    let (pg_handle, start_pg_result) =
+    {
        // Enter startup tracing context
        let _startup_context_guard = startup_context_from_env();

-        let cli_args = process_cli(&clap_args)?;
+        let cli_result = process_cli(&clap_args)?;

-        let cli_spec = try_spec_from_cli(&clap_args, &cli_args)?;
-
-        let wait_spec_result = wait_spec(build_tag, cli_args, cli_spec)?;
+        let wait_spec_result = wait_spec(build_tag, cli_result)?;

        start_postgres(&clap_args, wait_spec_result)?

-        // Startup is finished, exit the startup tracing span
+        // Startup is finished, exit the startup tracing context
    };

    // PostgreSQL is now running, if startup was successful. Wait until it exits.
    let wait_pg_result = wait_postgres(pg_handle)?;

-    let delay_exit = cleanup_after_postgres_exit(start_pg_result)?;
-
-    maybe_delay_exit(delay_exit);
-
-    deinit_and_exit(wait_pg_result);
+    cleanup_and_exit(start_pg_result, wait_pg_result)
 }

 fn init() -> Result<(String, clap::ArgMatches)> {
@@ -115,63 +109,8 @@ fn init() -> Result<(String, clap::ArgMatches)> {
    Ok((build_tag, cli().get_matches()))
 }

-fn process_cli(matches: &clap::ArgMatches) -> Result<ProcessCliResult> {
-    let pgbin_default = "postgres";
-    let pgbin = matches
-        .get_one::<String>("pgbin")
-        .map(|s| s.as_str())
-        .unwrap_or(pgbin_default);
-
-    let ext_remote_storage = matches
-        .get_one::<String>("remote-ext-config")
-        // Compatibility hack: if the control plane specified any remote-ext-config
-        // use the default value for extension storage proxy gateway.
-        // Remove this once the control plane is updated to pass the gateway URL
-        .map(|conf| {
-            if conf.starts_with("http") {
-                conf.trim_end_matches('/')
-            } else {
-                "http://pg-ext-s3-gateway"
-            }
-        });
-
-    let http_port = *matches
-        .get_one::<u16>("http-port")
-        .expect("http-port is required");
-    let pgdata = matches
-        .get_one::<String>("pgdata")
-        .expect("PGDATA path is required");
-    let connstr = matches
-        .get_one::<String>("connstr")
-        .expect("Postgres connection string is required");
-    let spec_json = matches.get_one::<String>("spec");
-    let spec_path = matches.get_one::<String>("spec-path");
-    let resize_swap_on_bind = matches.get_flag("resize-swap-on-bind");
-
-    Ok(ProcessCliResult {
-        connstr,
-        pgdata,
-        pgbin,
-        ext_remote_storage,
-        http_port,
-        spec_json,
-        spec_path,
-        resize_swap_on_bind,
-    })
-}
-
-struct ProcessCliResult<'clap> {
-    connstr: &'clap str,
-    pgdata: &'clap str,
-    pgbin: &'clap str,
-    ext_remote_storage: Option<&'clap str>,
-    http_port: u16,
-    spec_json: Option<&'clap String>,
-    spec_path: Option<&'clap String>,
-    resize_swap_on_bind: bool,
-}
-
-fn startup_context_from_env() -> Option<opentelemetry::ContextGuard> {
+fn startup_context_from_env() -> Option<opentelemetry::ContextGuard>
+{
    // Extract OpenTelemetry context for the startup actions from the
    // TRACEPARENT and TRACESTATE env variables, and attach it to the current
    // tracing context.
@@ -221,14 +160,39 @@ fn startup_context_from_env() -> Option<opentelemetry::ContextGuard> {
    }
 }

-fn try_spec_from_cli(
+fn process_cli(
    matches: &clap::ArgMatches,
-    ProcessCliResult {
-        spec_json,
-        spec_path,
-        ..
-    }: &ProcessCliResult,
-) -> Result<CliSpecParams> {
+) -> Result<ProcessCliResult> {
+    let pgbin_default = "postgres";
+    let pgbin = matches
+        .get_one::<String>("pgbin")
+        .map(|s| s.as_str())
+        .unwrap_or(pgbin_default);
+
+    let ext_remote_storage = matches
+        .get_one::<String>("remote-ext-config")
+        // Compatibility hack: if the control plane specified any remote-ext-config
+        // use the default value for extension storage proxy gateway.
+        // Remove this once the control plane is updated to pass the gateway URL
+        .map(|conf| {
+            if conf.starts_with("http") {
+                conf.trim_end_matches('/')
+            } else {
+                "http://pg-ext-s3-gateway"
+            }
+        });
+
+    let http_port = *matches
+        .get_one::<u16>("http-port")
+        .expect("http-port is required");
+    let pgdata = matches
+        .get_one::<String>("pgdata")
+        .expect("PGDATA path is required");
+    let connstr = matches
+        .get_one::<String>("connstr")
+        .expect("Postgres connection string is required");
+    let spec_json = matches.get_one::<String>("spec");
+    let spec_path = matches.get_one::<String>("spec-path");
    let compute_id = matches.get_one::<String>("compute-id");
    let control_plane_uri = matches.get_one::<String>("control-plane-uri");

@@ -269,13 +233,28 @@ fn try_spec_from_cli(
        }
    };

-    Ok(CliSpecParams {
+    let result = ProcessCliResult {
+        // directly from CLI:
+        connstr,
+        pgdata,
+        pgbin,
+        ext_remote_storage,
+        http_port,
+        // others:
        spec,
        live_config_allowed,
-    })
+    };
+
+    Ok(result)
 }

-struct CliSpecParams {
+struct ProcessCliResult<'clap> {
+    connstr: &'clap str,
+    pgdata: &'clap str,
+    pgbin: &'clap str,
+    ext_remote_storage: Option<&'clap str>,
+    http_port: u16,
+
    /// If a spec was provided via CLI or file, the [`ComputeSpec`]
    spec: Option<ComputeSpec>,
    live_config_allowed: bool,
@@ -288,14 +267,10 @@ fn wait_spec(
        pgdata,
        pgbin,
        ext_remote_storage,
-        resize_swap_on_bind,
        http_port,
-        ..
-    }: ProcessCliResult,
-    CliSpecParams {
        spec,
        live_config_allowed,
-    }: CliSpecParams,
+    }: ProcessCliResult,
 ) -> Result<WaitSpecResult> {
    let mut new_state = ComputeState::new();
    let spec_set;
@@ -324,14 +299,14 @@ fn wait_spec(

    // If this is a pooled VM, prewarm before starting HTTP server and becoming
    // available for binding. Prewarming helps Postgres start quicker later,
-    // because QEMU will already have its memory allocated from the host, and
+    // because QEMU will already have it's memory allocated from the host, and
    // the necessary binaries will already be cached.
    if !spec_set {
        compute.prewarm_postgres()?;
    }

-    // Launch http service first, so that we can serve control-plane requests
-    // while configuration is still in progress.
+    // Launch http service first, so we were able to serve control-plane
+    // requests, while configuration is still in progress.
    let _http_handle =
        launch_http_server(http_port, &compute).expect("cannot launch http endpoint thread");

@@ -349,45 +324,34 @@ fn wait_spec(
                break;
            }
        }
-
-        // Record for how long we slept waiting for the spec.
-        let now = Utc::now();
-        state.metrics.wait_for_spec_ms = now
-            .signed_duration_since(state.start_time)
-            .to_std()
-            .unwrap()
-            .as_millis() as u64;
-
-        // Reset start time, so that the total startup time that is calculated later will
-        // not include the time that we waited for the spec.
-        state.start_time = now;
    }

-    Ok(WaitSpecResult {
-        compute,
-        http_port,
-        resize_swap_on_bind,
-    })
+    Ok(WaitSpecResult { compute, http_port })
 }

 struct WaitSpecResult {
    compute: Arc<ComputeNode>,
    // passed through from ProcessCliResult
    http_port: u16,
-    resize_swap_on_bind: bool,
 }

 fn start_postgres(
-    // need to allow unused because `matches` is only used if target_os = "linux"
-    #[allow(unused_variables)] matches: &clap::ArgMatches,
-    WaitSpecResult {
-        compute,
-        http_port,
-        resize_swap_on_bind,
-    }: WaitSpecResult,
+    matches: &clap::ArgMatches,
+    WaitSpecResult { compute, http_port }: WaitSpecResult,
 ) -> Result<(Option<PostgresHandle>, StartPostgresResult)> {
    // We got all we need, update the state.
    let mut state = compute.state.lock().unwrap();
+
+    // Record for how long we slept waiting for the spec.
+    state.metrics.wait_for_spec_ms = Utc::now()
+        .signed_duration_since(state.start_time)
+        .to_std()
+        .unwrap()
+        .as_millis() as u64;
+    // Reset start time to the actual start of the configuration, so that
+    // total startup time was properly measured at the end.
+    state.start_time = Utc::now();
+
    state.status = ComputeStatus::Init;
    compute.state_changed.notify_all();

@@ -395,72 +359,34 @@ fn start_postgres(
        "running compute with features: {:?}",
        state.pspec.as_ref().unwrap().spec.features
    );
-    // before we release the mutex, fetch the swap size (if any) for later.
-    let swap_size_bytes = state.pspec.as_ref().unwrap().spec.swap_size_bytes;
    drop(state);

    // Launch remaining service threads
    let _monitor_handle = launch_monitor(&compute);
    let _configurator_handle = launch_configurator(&compute);

-    let mut prestartup_failed = false;
-    let mut delay_exit = false;
-
-    // Resize swap to the desired size if the compute spec says so
-    if let (Some(size_bytes), true) = (swap_size_bytes, resize_swap_on_bind) {
-        // To avoid 'swapoff' hitting postgres startup, we need to run resize-swap to completion
-        // *before* starting postgres.
-        //
-        // In theory, we could do this asynchronously if SkipSwapon was enabled for VMs, but this
-        // carries a risk of introducing hard-to-debug issues - e.g. if postgres sometimes gets
-        // OOM-killed during startup because swap wasn't available yet.
-        match resize_swap(size_bytes) {
-            Ok(()) => {
-                let size_gib = size_bytes as f32 / (1 << 20) as f32; // just for more coherent display.
-                info!(%size_bytes, %size_gib, "resized swap");
-            }
-            Err(err) => {
-                let err = err.context("failed to resize swap");
-                error!("{err:#}");
-
-                // Mark compute startup as failed; don't try to start postgres, and report this
-                // error to the control plane when it next asks.
-                prestartup_failed = true;
-                let mut state = compute.state.lock().unwrap();
-                state.error = Some(format!("{err:?}"));
-                state.status = ComputeStatus::Failed;
-                compute.state_changed.notify_all();
-                delay_exit = true;
-            }
-        }
-    }
-
    let extension_server_port: u16 = http_port;

    // Start Postgres
-    let mut pg = None;
-    if !prestartup_failed {
-        pg = match compute.start_compute(extension_server_port) {
-            Ok(pg) => Some(pg),
-            Err(err) => {
-                error!("could not start the compute node: {:#}", err);
-                let mut state = compute.state.lock().unwrap();
-                state.error = Some(format!("{:?}", err));
-                state.status = ComputeStatus::Failed;
-                // Notify others that Postgres failed to start. In case of configuring the
-                // empty compute, it's likely that API handler is still waiting for compute
-                // state change. With this we will notify it that compute is in Failed state,
-                // so control plane will know about it earlier and record proper error instead
-                // of timeout.
-                compute.state_changed.notify_all();
-                drop(state); // unlock
-                delay_exit = true;
-                None
-            }
-        };
-    } else {
-        warn!("skipping postgres startup because pre-startup step failed");
-    }
+    let mut delay_exit = false;
+    let pg = match compute.start_compute(extension_server_port) {
+        Ok(pg) => Some(pg),
+        Err(err) => {
+            error!("could not start the compute node: {:#}", err);
+            let mut state = compute.state.lock().unwrap();
+            state.error = Some(format!("{:?}", err));
+            state.status = ComputeStatus::Failed;
+            // Notify others that Postgres failed to start. In case of configuring the
+            // empty compute, it's likely that API handler is still waiting for compute
+            // state change. With this we will notify it that compute is in Failed state,
+            // so control plane will know about it earlier and record proper error instead
+            // of timeout.
+            compute.state_changed.notify_all();
+            drop(state); // unlock
+            delay_exit = true;
+            None
+        }
+    };

    // Start the vm-monitor if directed to. The vm-monitor only runs on linux
    // because it requires cgroups.
@@ -536,7 +462,9 @@ struct StartPostgresResult {
    vm_monitor: Option<tokio::task::JoinHandle<Result<()>>>,
 }

-fn wait_postgres(pg: Option<PostgresHandle>) -> Result<WaitPostgresResult> {
+fn wait_postgres(
+    pg: Option<PostgresHandle>,
+) -> Result<WaitPostgresResult> {
    // Wait for the child Postgres process forever. In this state Ctrl+C will
    // propagate to Postgres and it will be shut down as well.
    let mut exit_code = None;
@@ -562,7 +490,7 @@ struct WaitPostgresResult {
    exit_code: Option<i32>,
 }

-fn cleanup_after_postgres_exit(
+fn cleanup_and_exit(
    StartPostgresResult {
        mut delay_exit,
        compute,
@@ -573,7 +501,8 @@ fn cleanup_after_postgres_exit(
        #[cfg(target_os = "linux")]
        rt,
    }: StartPostgresResult,
-) -> Result<bool> {
+    WaitPostgresResult { exit_code }: WaitPostgresResult,
+) -> Result<()> {
    // Terminate the vm_monitor so it releases the file watcher on
    // /sys/fs/cgroup/neon-postgres.
    // Note: the vm-monitor only runs on linux because it requires cgroups.
@@ -615,19 +544,13 @@ fn cleanup_after_postgres_exit(
        error!("error while checking for core dumps: {err:?}");
    }

-    Ok(delay_exit)
-}
-
-fn maybe_delay_exit(delay_exit: bool) {
    // 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));
    }
-}

-fn deinit_and_exit(WaitPostgresResult { exit_code }: WaitPostgresResult) -> ! {
    // Shutdown trace pipeline gracefully, so that it has a chance to send any
    // pending traces before we exit. Shutting down OTEL tracing provider may
    // hang for quite some time, see, for example:
@@ -739,11 +662,6 @@ fn cli() -> clap::Command {
                )
                .value_name("FILECACHE_CONNSTR"),
        )
-        .arg(
-            Arg::new("resize-swap-on-bind")
-                .long("resize-swap-on-bind")
-                .action(clap::ArgAction::SetTrue),
-        )
 }

 /// When compute_ctl is killed, send also termination signal to sync-safekeepers
--- a/compute_tools/src/lib.rs
+++ b/compute_tools/src/lib.rs
@@ -14,5 +14,4 @@ pub mod monitor;
 pub mod params;
 pub mod pg_helpers;
 pub mod spec;
-pub mod swap;
 pub mod sync_sk;
--- a/compute_tools/src/spec.rs
+++ b/compute_tools/src/spec.rs
@@ -490,7 +490,7 @@ pub fn handle_databases(spec: &ComputeSpec, client: &mut Client) -> Result<()> {
                "rename_db" => {
                    let new_name = op.new_name.as_ref().unwrap();

-                    if existing_dbs.contains_key(&op.name) {
+                    if existing_dbs.get(&op.name).is_some() {
                        let query: String = format!(
                            "ALTER DATABASE {} RENAME TO {}",
                            op.name.pg_quote(),
--- a/compute_tools/src/swap.rs
+++ b/compute_tools/src/swap.rs
@@ -1,36 +0,0 @@
-use anyhow::{anyhow, Context};
-use tracing::warn;
-
-pub const RESIZE_SWAP_BIN: &str = "/neonvm/bin/resize-swap";
-
-pub fn resize_swap(size_bytes: u64) -> anyhow::Result<()> {
-    // run `/neonvm/bin/resize-swap --once {size_bytes}`
-    //
-    // Passing '--once' causes resize-swap to delete itself after successful completion, which
-    // means that if compute_ctl restarts later, we won't end up calling 'swapoff' while
-    // postgres is running.
-    //
-    // NOTE: resize-swap is not very clever. If present, --once MUST be the first arg.
-    let child_result = std::process::Command::new("/usr/bin/sudo")
-        .arg(RESIZE_SWAP_BIN)
-        .arg("--once")
-        .arg(size_bytes.to_string())
-        .spawn();
-
-    if matches!(&child_result, Err(e) if e.kind() == std::io::ErrorKind::NotFound) {
-        warn!("ignoring \"not found\" error from resize-swap to avoid swapoff while compute is running");
-        return Ok(());
-    }
-
-    child_result
-        .context("spawn() failed")
-        .and_then(|mut child| child.wait().context("wait() failed"))
-        .and_then(|status| match status.success() {
-            true => Ok(()),
-            false => Err(anyhow!("process exited with {status}")),
-        })
-        // wrap any prior error with the overall context that we couldn't run the command
-        .with_context(|| {
-            format!("could not run `/usr/bin/sudo {RESIZE_SWAP_BIN} --once {size_bytes}`")
-        })
-}
--- a/control_plane/Cargo.toml
+++ b/control_plane/Cargo.toml
@@ -28,7 +28,6 @@ serde_with.workspace = true
 tar.workspace = true
 thiserror.workspace = true
 toml.workspace = true
-toml_edit.workspace = true
 tokio.workspace = true
 tokio-postgres.workspace = true
 tokio-util.workspace = true
--- a/control_plane/src/bin/neon_local.rs
+++ b/control_plane/src/bin/neon_local.rs
@@ -9,23 +9,20 @@ use anyhow::{anyhow, bail, Context, Result};
 use clap::{value_parser, Arg, ArgAction, ArgMatches, Command, ValueEnum};
 use compute_api::spec::ComputeMode;
 use control_plane::endpoint::ComputeControlPlane;
-use control_plane::local_env::{
-    InitForceMode, LocalEnv, NeonBroker, NeonLocalInitConf, NeonLocalInitPageserverConf,
-    SafekeeperConf,
-};
-use control_plane::pageserver::PageServerNode;
+use control_plane::local_env::{InitForceMode, LocalEnv};
+use control_plane::pageserver::{PageServerNode, PAGESERVER_REMOTE_STORAGE_DIR};
 use control_plane::safekeeper::SafekeeperNode;
 use control_plane::storage_controller::StorageController;
 use control_plane::{broker, local_env};
-use pageserver_api::config::{
-    DEFAULT_HTTP_LISTEN_PORT as DEFAULT_PAGESERVER_HTTP_PORT,
-    DEFAULT_PG_LISTEN_PORT as DEFAULT_PAGESERVER_PG_PORT,
-};
 use pageserver_api::controller_api::PlacementPolicy;
 use pageserver_api::models::{
    ShardParameters, TenantCreateRequest, TimelineCreateRequest, TimelineInfo,
 };
 use pageserver_api::shard::{ShardCount, ShardStripeSize, TenantShardId};
+use pageserver_api::{
+    DEFAULT_HTTP_LISTEN_PORT as DEFAULT_PAGESERVER_HTTP_PORT,
+    DEFAULT_PG_LISTEN_PORT as DEFAULT_PAGESERVER_PG_PORT,
+};
 use postgres_backend::AuthType;
 use postgres_connection::parse_host_port;
 use safekeeper_api::{
@@ -55,6 +52,44 @@ const DEFAULT_PG_VERSION: &str = "15";

 const DEFAULT_PAGESERVER_CONTROL_PLANE_API: &str = "http://127.0.0.1:1234/upcall/v1/";

+fn default_conf(num_pageservers: u16) -> String {
+    let mut template = format!(
+        r#"
+# Default built-in configuration, defined in main.rs
+control_plane_api = '{DEFAULT_PAGESERVER_CONTROL_PLANE_API}'
+
+[broker]
+listen_addr = '{DEFAULT_BROKER_ADDR}'
+
+[[safekeepers]]
+id = {DEFAULT_SAFEKEEPER_ID}
+pg_port = {DEFAULT_SAFEKEEPER_PG_PORT}
+http_port = {DEFAULT_SAFEKEEPER_HTTP_PORT}
+
+"#,
+    );
+
+    for i in 0..num_pageservers {
+        let pageserver_id = NodeId(DEFAULT_PAGESERVER_ID.0 + i as u64);
+        let pg_port = DEFAULT_PAGESERVER_PG_PORT + i;
+        let http_port = DEFAULT_PAGESERVER_HTTP_PORT + i;
+
+        template += &format!(
+            r#"
+[[pageservers]]
+id = {pageserver_id}
+listen_pg_addr = '127.0.0.1:{pg_port}'
+listen_http_addr = '127.0.0.1:{http_port}'
+pg_auth_type = '{trust_auth}'
+http_auth_type = '{trust_auth}'
+"#,
+            trust_auth = AuthType::Trust,
+        )
+    }
+
+    template
+}
+
 ///
 /// Timelines tree element used as a value in the HashMap.
 ///
@@ -98,7 +133,7 @@ fn main() -> Result<()> {
        let subcommand_result = match sub_name {
            "tenant" => rt.block_on(handle_tenant(sub_args, &mut env)),
            "timeline" => rt.block_on(handle_timeline(sub_args, &mut env)),
-            "start" => rt.block_on(handle_start_all(&env)),
+            "start" => rt.block_on(handle_start_all(sub_args, &env)),
            "stop" => rt.block_on(handle_stop_all(sub_args, &env)),
            "pageserver" => rt.block_on(handle_pageserver(sub_args, &env)),
            "storage_controller" => rt.block_on(handle_storage_controller(sub_args, &env)),
@@ -117,7 +152,7 @@ fn main() -> Result<()> {
    };

    match subcommand_result {
-        Ok(Some(updated_env)) => updated_env.persist_config()?,
+        Ok(Some(updated_env)) => updated_env.persist_config(&updated_env.base_data_dir)?,
        Ok(None) => (),
        Err(e) => {
            eprintln!("command failed: {e:?}");
@@ -306,65 +341,48 @@ fn parse_timeline_id(sub_match: &ArgMatches) -> anyhow::Result<Option<TimelineId
 }

 fn handle_init(init_match: &ArgMatches) -> anyhow::Result<LocalEnv> {
-    let num_pageservers = init_match.get_one::<u16>("num-pageservers");
-
-    let force = init_match.get_one("force").expect("we set a default value");
-
-    // Create the in-memory `LocalEnv` that we'd normally load from disk in `load_config`.
-    let init_conf: NeonLocalInitConf = if let Some(config_path) =
-        init_match.get_one::<PathBuf>("config")
-    {
-        // User (likely the Python test suite) provided a description of the environment.
-        if num_pageservers.is_some() {
-            bail!("Cannot specify both --num-pageservers and --config, use key `pageservers` in the --config file instead");
-        }
+    let num_pageservers = init_match
+        .get_one::<u16>("num-pageservers")
+        .expect("num-pageservers arg has a default");
+    // Create config file
+    let toml_file: String = if let Some(config_path) = init_match.get_one::<PathBuf>("config") {
        // load and parse the file
-        let contents = std::fs::read_to_string(config_path).with_context(|| {
+        std::fs::read_to_string(config_path).with_context(|| {
            format!(
                "Could not read configuration file '{}'",
                config_path.display()
            )
-        })?;
-        toml_edit::de::from_str(&contents)?
+        })?
    } else {
-        // User (likely interactive) did not provide a description of the environment, give them the default
-        NeonLocalInitConf {
-            control_plane_api: Some(Some(DEFAULT_PAGESERVER_CONTROL_PLANE_API.parse().unwrap())),
-            broker: NeonBroker {
-                listen_addr: DEFAULT_BROKER_ADDR.parse().unwrap(),
-            },
-            safekeepers: vec![SafekeeperConf {
-                id: DEFAULT_SAFEKEEPER_ID,
-                pg_port: DEFAULT_SAFEKEEPER_PG_PORT,
-                http_port: DEFAULT_SAFEKEEPER_HTTP_PORT,
-                ..Default::default()
-            }],
-            pageservers: (0..num_pageservers.copied().unwrap_or(1))
-                .map(|i| {
-                    let pageserver_id = NodeId(DEFAULT_PAGESERVER_ID.0 + i as u64);
-                    let pg_port = DEFAULT_PAGESERVER_PG_PORT + i;
-                    let http_port = DEFAULT_PAGESERVER_HTTP_PORT + i;
-                    NeonLocalInitPageserverConf {
-                        id: pageserver_id,
-                        listen_pg_addr: format!("127.0.0.1:{pg_port}"),
-                        listen_http_addr: format!("127.0.0.1:{http_port}"),
-                        pg_auth_type: AuthType::Trust,
-                        http_auth_type: AuthType::Trust,
-                        other: Default::default(),
-                    }
-                })
-                .collect(),
-            pg_distrib_dir: None,
-            neon_distrib_dir: None,
-            default_tenant_id: TenantId::from_array(std::array::from_fn(|_| 0)),
-            storage_controller: None,
-            control_plane_compute_hook_api: None,
-        }
+        // Built-in default config
+        default_conf(*num_pageservers)
    };

-    LocalEnv::init(init_conf, force)
-        .context("materialize initial neon_local environment on disk")?;
-    Ok(LocalEnv::load_config().expect("freshly written config should be loadable"))
+    let pg_version = init_match
+        .get_one::<u32>("pg-version")
+        .copied()
+        .context("Failed to parse postgres version from the argument string")?;
+
+    let mut env =
+        LocalEnv::parse_config(&toml_file).context("Failed to create neon configuration")?;
+    let force = init_match.get_one("force").expect("we set a default value");
+    env.init(pg_version, force)
+        .context("Failed to initialize neon repository")?;
+
+    // Create remote storage location for default LocalFs remote storage
+    std::fs::create_dir_all(env.base_data_dir.join(PAGESERVER_REMOTE_STORAGE_DIR))?;
+
+    // Initialize pageserver, create initial tenant and timeline.
+    for ps_conf in &env.pageservers {
+        PageServerNode::from_env(&env, ps_conf)
+            .initialize(&pageserver_config_overrides(init_match))
+            .unwrap_or_else(|e| {
+                eprintln!("pageserver init failed: {e:?}");
+                exit(1);
+            });
+    }
+
+    Ok(env)
 }

 /// The default pageserver is the one where CLI tenant/timeline operations are sent by default.
@@ -379,6 +397,15 @@ fn get_default_pageserver(env: &local_env::LocalEnv) -> PageServerNode {
    PageServerNode::from_env(env, ps_conf)
 }

+fn pageserver_config_overrides(init_match: &ArgMatches) -> Vec<&str> {
+    init_match
+        .get_many::<String>("pageserver-config-override")
+        .into_iter()
+        .flatten()
+        .map(String::as_str)
+        .collect()
+}
+
 async fn handle_tenant(
    tenant_match: &ArgMatches,
    env: &mut local_env::LocalEnv,
@@ -810,8 +837,6 @@ async fn handle_endpoint(ep_match: &ArgMatches, env: &local_env::LocalEnv) -> Re
                .copied()
                .unwrap_or(false);

-            let allow_multiple = sub_args.get_flag("allow-multiple");
-
            let mode = match (lsn, hot_standby) {
                (Some(lsn), false) => ComputeMode::Static(lsn),
                (None, true) => ComputeMode::Replica,
@@ -829,9 +854,7 @@ async fn handle_endpoint(ep_match: &ArgMatches, env: &local_env::LocalEnv) -> Re
                _ => {}
            }

-            if !allow_multiple {
-                cplane.check_conflicting_endpoints(mode, tenant_id, timeline_id)?;
-            }
+            cplane.check_conflicting_endpoints(mode, tenant_id, timeline_id)?;

            cplane.new_endpoint(
                &endpoint_id,
@@ -860,8 +883,6 @@ async fn handle_endpoint(ep_match: &ArgMatches, env: &local_env::LocalEnv) -> Re

            let remote_ext_config = sub_args.get_one::<String>("remote-ext-config");

-            let allow_multiple = sub_args.get_flag("allow-multiple");
-
            // If --safekeepers argument is given, use only the listed safekeeper nodes.
            let safekeepers =
                if let Some(safekeepers_str) = sub_args.get_one::<String>("safekeepers") {
@@ -887,13 +908,11 @@ async fn handle_endpoint(ep_match: &ArgMatches, env: &local_env::LocalEnv) -> Re
                .cloned()
                .unwrap_or_default();

-            if !allow_multiple {
-                cplane.check_conflicting_endpoints(
-                    endpoint.mode,
-                    endpoint.tenant_id,
-                    endpoint.timeline_id,
-                )?;
-            }
+            cplane.check_conflicting_endpoints(
+                endpoint.mode,
+                endpoint.tenant_id,
+                endpoint.timeline_id,
+            )?;

            let (pageservers, stripe_size) = if let Some(pageserver_id) = pageserver_id {
                let conf = env.get_pageserver_conf(pageserver_id).unwrap();
@@ -1049,7 +1068,10 @@ fn get_pageserver(env: &local_env::LocalEnv, args: &ArgMatches) -> Result<PageSe
 async fn handle_pageserver(sub_match: &ArgMatches, env: &local_env::LocalEnv) -> Result<()> {
    match sub_match.subcommand() {
        Some(("start", subcommand_args)) => {
-            if let Err(e) = get_pageserver(env, subcommand_args)?.start().await {
+            if let Err(e) = get_pageserver(env, subcommand_args)?
+                .start(&pageserver_config_overrides(subcommand_args))
+                .await
+            {
                eprintln!("pageserver start failed: {e}");
                exit(1);
            }
@@ -1075,7 +1097,10 @@ async fn handle_pageserver(sub_match: &ArgMatches, env: &local_env::LocalEnv) ->
                exit(1);
            }

-            if let Err(e) = pageserver.start().await {
+            if let Err(e) = pageserver
+                .start(&pageserver_config_overrides(subcommand_args))
+                .await
+            {
                eprintln!("pageserver start failed: {e}");
                exit(1);
            }
@@ -1202,7 +1227,7 @@ async fn handle_safekeeper(sub_match: &ArgMatches, env: &local_env::LocalEnv) ->
    Ok(())
 }

-async fn handle_start_all(env: &local_env::LocalEnv) -> anyhow::Result<()> {
+async fn handle_start_all(sub_match: &ArgMatches, env: &local_env::LocalEnv) -> anyhow::Result<()> {
    // Endpoints are not started automatically

    broker::start_broker_process(env).await?;
@@ -1219,7 +1244,10 @@ async fn handle_start_all(env: &local_env::LocalEnv) -> anyhow::Result<()> {

    for ps_conf in &env.pageservers {
        let pageserver = PageServerNode::from_env(env, ps_conf);
-        if let Err(e) = pageserver.start().await {
+        if let Err(e) = pageserver
+            .start(&pageserver_config_overrides(sub_match))
+            .await
+        {
            eprintln!("pageserver {} start failed: {:#}", ps_conf.id, e);
            try_stop_all(env, true).await;
            exit(1);
@@ -1360,6 +1388,13 @@ fn cli() -> Command {
        .required(false)
        .value_name("stop-mode");

+    let pageserver_config_args = Arg::new("pageserver-config-override")
+        .long("pageserver-config-override")
+        .num_args(1)
+        .action(ArgAction::Append)
+        .help("Additional pageserver's configuration options or overrides, refer to pageserver's 'config-override' CLI parameter docs for more")
+        .required(false);
+
    let remote_ext_config_args = Arg::new("remote-ext-config")
        .long("remote-ext-config")
        .num_args(1)
@@ -1393,7 +1428,9 @@ fn cli() -> Command {
    let num_pageservers_arg = Arg::new("num-pageservers")
        .value_parser(value_parser!(u16))
        .long("num-pageservers")
-        .help("How many pageservers to create (default 1)");
+        .help("How many pageservers to create (default 1)")
+        .required(false)
+        .default_value("1");

    let update_catalog = Arg::new("update-catalog")
        .value_parser(value_parser!(bool))
@@ -1407,25 +1444,20 @@ fn cli() -> Command {
        .help("If set, will create test user `user` and `neondb` database. Requires `update-catalog = true`")
        .required(false);

-    let allow_multiple = Arg::new("allow-multiple")
-        .help("Allow multiple primary endpoints running on the same branch. Shouldn't be used normally, but useful for tests.")
-        .long("allow-multiple")
-        .action(ArgAction::SetTrue)
-        .required(false);
-
    Command::new("Neon CLI")
        .arg_required_else_help(true)
        .version(GIT_VERSION)
        .subcommand(
            Command::new("init")
                .about("Initialize a new Neon repository, preparing configs for services to start with")
+                .arg(pageserver_config_args.clone())
                .arg(num_pageservers_arg.clone())
                .arg(
                    Arg::new("config")
                        .long("config")
                        .required(false)
                        .value_parser(value_parser!(PathBuf))
-                        .value_name("config")
+                        .value_name("config"),
                )
                .arg(pg_version_arg.clone())
                .arg(force_arg)
@@ -1507,6 +1539,7 @@ fn cli() -> Command {
                .subcommand(Command::new("status"))
                .subcommand(Command::new("start")
                    .about("Start local pageserver")
+                    .arg(pageserver_config_args.clone())
                )
                .subcommand(Command::new("stop")
                    .about("Stop local pageserver")
@@ -1514,6 +1547,7 @@ fn cli() -> Command {
                )
                .subcommand(Command::new("restart")
                    .about("Restart local pageserver")
+                    .arg(pageserver_config_args.clone())
                )
        )
        .subcommand(
@@ -1567,7 +1601,6 @@ fn cli() -> Command {
                    .arg(pg_version_arg.clone())
                    .arg(hot_standby_arg.clone())
                    .arg(update_catalog)
-                    .arg(allow_multiple.clone())
                )
                .subcommand(Command::new("start")
                    .about("Start postgres.\n If the endpoint doesn't exist yet, it is created.")
@@ -1576,7 +1609,6 @@ fn cli() -> Command {
                    .arg(safekeepers_arg)
                    .arg(remote_ext_config_args)
                    .arg(create_test_user)
-                    .arg(allow_multiple.clone())
                )
                .subcommand(Command::new("reconfigure")
                            .about("Reconfigure the endpoint")
@@ -1628,6 +1660,7 @@ fn cli() -> Command {
        .subcommand(
            Command::new("start")
                .about("Start page server and safekeepers")
+                .arg(pageserver_config_args)
        )
        .subcommand(
            Command::new("stop")
--- a/control_plane/src/endpoint.rs
+++ b/control_plane/src/endpoint.rs
@@ -554,7 +554,6 @@ impl Endpoint {
            format_version: 1.0,
            operation_uuid: None,
            features: self.features.clone(),
-            swap_size_bytes: None,
            cluster: Cluster {
                cluster_id: None, // project ID: not used
                name: None,       // project name: not used
--- a/control_plane/src/local_env.rs
+++ b/control_plane/src/local_env.rs
@@ -3,7 +3,7 @@
 //! Now it also provides init method which acts like a stub for proper installation
 //! script which will use local paths.

-use anyhow::{bail, Context};
+use anyhow::{bail, ensure, Context};

 use clap::ValueEnum;
 use postgres_backend::AuthType;
@@ -23,8 +23,6 @@ use utils::{
    id::{NodeId, TenantId, TenantTimelineId, TimelineId},
 };

-use crate::pageserver::PageServerNode;
-use crate::pageserver::PAGESERVER_REMOTE_STORAGE_DIR;
 use crate::safekeeper::SafekeeperNode;

 pub const DEFAULT_PG_VERSION: u32 = 15;
@@ -36,7 +34,7 @@ pub const DEFAULT_PG_VERSION: u32 = 15;
 // to 'neon_local init --config=<path>' option. See control_plane/simple.conf for
 // an example.
 //
-#[derive(PartialEq, Eq, Clone, Debug)]
+#[derive(Serialize, Deserialize, PartialEq, Eq, Clone, Debug)]
 pub struct LocalEnv {
    // Base directory for all the nodes (the pageserver, safekeepers and
    // compute endpoints).
@@ -44,99 +42,59 @@ pub struct LocalEnv {
    // This is not stored in the config file. Rather, this is the path where the
    // config file itself is. It is read from the NEON_REPO_DIR env variable or
    // '.neon' if not given.
+    #[serde(skip)]
    pub base_data_dir: PathBuf,

    // Path to postgres distribution. It's expected that "bin", "include",
    // "lib", "share" from postgres distribution are there. If at some point
    // in time we will be able to run against vanilla postgres we may split that
    // to four separate paths and match OS-specific installation layout.
+    #[serde(default)]
    pub pg_distrib_dir: PathBuf,

    // Path to pageserver binary.
+    #[serde(default)]
    pub neon_distrib_dir: PathBuf,

    // Default tenant ID to use with the 'neon_local' command line utility, when
    // --tenant_id is not explicitly specified.
+    #[serde(default)]
    pub default_tenant_id: Option<TenantId>,

    // used to issue tokens during e.g pg start
+    #[serde(default)]
    pub private_key_path: PathBuf,

    pub broker: NeonBroker,

    // Configuration for the storage controller (1 per neon_local environment)
+    #[serde(default)]
    pub storage_controller: NeonStorageControllerConf,

    /// This Vec must always contain at least one pageserver
-    /// Populdated by [`Self::load_config`] from the individual `pageserver.toml`s.
-    /// NB: not used anymore except for informing users that they need to change their `.neon/config`.
    pub pageservers: Vec<PageServerConf>,

+    #[serde(default)]
    pub safekeepers: Vec<SafekeeperConf>,

    // Control plane upcall API for pageserver: if None, we will not run storage_controller  If set, this will
    // be propagated into each pageserver's configuration.
+    #[serde(default)]
    pub control_plane_api: Option<Url>,

    // Control plane upcall API for storage controller.  If set, this will be propagated into the
    // storage controller's configuration.
+    #[serde(default)]
    pub control_plane_compute_hook_api: Option<Url>,

    /// Keep human-readable aliases in memory (and persist them to config), to hide ZId hex strings from the user.
+    #[serde(default)]
    // A `HashMap<String, HashMap<TenantId, TimelineId>>` would be more appropriate here,
    // but deserialization into a generic toml object as `toml::Value::try_from` fails with an error.
    // https://toml.io/en/v1.0.0 does not contain a concept of "a table inside another table".
-    pub branch_name_mappings: HashMap<String, Vec<(TenantId, TimelineId)>>,
-}
-
-/// On-disk state stored in `.neon/config`.
-#[derive(PartialEq, Eq, Clone, Debug, Default, Serialize, Deserialize)]
-#[serde(default, deny_unknown_fields)]
-pub struct OnDiskConfig {
-    pub pg_distrib_dir: PathBuf,
-    pub neon_distrib_dir: PathBuf,
-    pub default_tenant_id: Option<TenantId>,
-    pub private_key_path: PathBuf,
-    pub broker: NeonBroker,
-    pub storage_controller: NeonStorageControllerConf,
-    #[serde(
-        skip_serializing,
-        deserialize_with = "fail_if_pageservers_field_specified"
-    )]
-    pub pageservers: Vec<PageServerConf>,
-    pub safekeepers: Vec<SafekeeperConf>,
-    pub control_plane_api: Option<Url>,
-    pub control_plane_compute_hook_api: Option<Url>,
    branch_name_mappings: HashMap<String, Vec<(TenantId, TimelineId)>>,
 }

-fn fail_if_pageservers_field_specified<'de, D>(_: D) -> Result<Vec<PageServerConf>, D::Error>
-where
-    D: serde::Deserializer<'de>,
-{
-    Err(serde::de::Error::custom(
-        "The 'pageservers' field is no longer used; pageserver.toml is now authoritative; \
-         Please remove the `pageservers` from your .neon/config.",
-    ))
-}
-
-/// The description of the neon_local env to be initialized by `neon_local init --config`.
-#[derive(Clone, Debug, Deserialize)]
-#[serde(deny_unknown_fields)]
-pub struct NeonLocalInitConf {
-    // TODO: do we need this? Seems unused
-    pub pg_distrib_dir: Option<PathBuf>,
-    // TODO: do we need this? Seems unused
-    pub neon_distrib_dir: Option<PathBuf>,
-    pub default_tenant_id: TenantId,
-    pub broker: NeonBroker,
-    pub storage_controller: Option<NeonStorageControllerConf>,
-    pub pageservers: Vec<NeonLocalInitPageserverConf>,
-    pub safekeepers: Vec<SafekeeperConf>,
-    pub control_plane_api: Option<Option<Url>>,
-    pub control_plane_compute_hook_api: Option<Option<Url>>,
-}
-
 /// Broker config for cluster internal communication.
 #[derive(Serialize, Deserialize, PartialEq, Eq, Clone, Debug)]
 #[serde(default)]
@@ -183,18 +141,24 @@ impl NeonBroker {
    }
 }

-// neon_local needs to know this subset of pageserver configuration.
-// For legacy reasons, this information is duplicated from `pageserver.toml` into `.neon/config`.
-// It can get stale if `pageserver.toml` is changed.
-// TODO(christian): don't store this at all in `.neon/config`, always load it from `pageserver.toml`
 #[derive(Serialize, Deserialize, PartialEq, Eq, Clone, Debug)]
 #[serde(default, deny_unknown_fields)]
 pub struct PageServerConf {
+    // node id
    pub id: NodeId,
+
+    // Pageserver connection settings
    pub listen_pg_addr: String,
    pub listen_http_addr: String,
+
+    // auth type used for the PG and HTTP ports
    pub pg_auth_type: AuthType,
    pub http_auth_type: AuthType,
+
+    pub(crate) virtual_file_io_engine: Option<String>,
+    pub(crate) get_vectored_impl: Option<String>,
+    pub(crate) get_impl: Option<String>,
+    pub(crate) validate_vectored_get: Option<bool>,
 }

 impl Default for PageServerConf {
@@ -205,40 +169,10 @@ impl Default for PageServerConf {
            listen_http_addr: String::new(),
            pg_auth_type: AuthType::Trust,
            http_auth_type: AuthType::Trust,
-        }
-    }
-}
-
-/// The toml that can be passed to `neon_local init --config`.
-/// This is a subset of the `pageserver.toml` configuration.
-// TODO(christian): use pageserver_api::config::ConfigToml (PR #7656)
-#[derive(Clone, Debug, serde::Deserialize, serde::Serialize)]
-pub struct NeonLocalInitPageserverConf {
-    pub id: NodeId,
-    pub listen_pg_addr: String,
-    pub listen_http_addr: String,
-    pub pg_auth_type: AuthType,
-    pub http_auth_type: AuthType,
-    #[serde(flatten)]
-    pub other: HashMap<String, toml::Value>,
-}
-
-impl From<&NeonLocalInitPageserverConf> for PageServerConf {
-    fn from(conf: &NeonLocalInitPageserverConf) -> Self {
-        let NeonLocalInitPageserverConf {
-            id,
-            listen_pg_addr,
-            listen_http_addr,
-            pg_auth_type,
-            http_auth_type,
-            other: _,
-        } = conf;
-        Self {
-            id: *id,
-            listen_pg_addr: listen_pg_addr.clone(),
-            listen_http_addr: listen_http_addr.clone(),
-            pg_auth_type: *pg_auth_type,
-            http_auth_type: *http_auth_type,
+            virtual_file_io_engine: None,
+            get_vectored_impl: None,
+            get_impl: None,
+            validate_vectored_get: None,
        }
    }
 }
@@ -426,7 +360,41 @@ impl LocalEnv {
            .collect()
    }

-    ///  Construct `Self` from on-disk state.
+    /// Create a LocalEnv from a config file.
+    ///
+    /// Unlike 'load_config', this function fills in any defaults that are missing
+    /// from the config file.
+    pub fn parse_config(toml: &str) -> anyhow::Result<Self> {
+        let mut env: LocalEnv = toml::from_str(toml)?;
+
+        // Find postgres binaries.
+        // Follow POSTGRES_DISTRIB_DIR if set, otherwise look in "pg_install".
+        // Note that later in the code we assume, that distrib dirs follow the same pattern
+        // for all postgres versions.
+        if env.pg_distrib_dir == Path::new("") {
+            if let Some(postgres_bin) = env::var_os("POSTGRES_DISTRIB_DIR") {
+                env.pg_distrib_dir = postgres_bin.into();
+            } else {
+                let cwd = env::current_dir()?;
+                env.pg_distrib_dir = cwd.join("pg_install")
+            }
+        }
+
+        // Find neon binaries.
+        if env.neon_distrib_dir == Path::new("") {
+            env.neon_distrib_dir = env::current_exe()?.parent().unwrap().to_owned();
+        }
+
+        if env.pageservers.is_empty() {
+            anyhow::bail!("Configuration must contain at least one pageserver");
+        }
+
+        env.base_data_dir = base_path();
+
+        Ok(env)
+    }
+
+    /// Locate and load config
    pub fn load_config() -> anyhow::Result<Self> {
        let repopath = base_path();

@@ -440,129 +408,38 @@ impl LocalEnv {
        // TODO: check that it looks like a neon repository

        // load and parse file
-        let config_file_contents = fs::read_to_string(repopath.join("config"))?;
-        let on_disk_config: OnDiskConfig = toml::from_str(config_file_contents.as_str())?;
-        let mut env = {
-            let OnDiskConfig {
-                pg_distrib_dir,
-                neon_distrib_dir,
-                default_tenant_id,
-                private_key_path,
-                broker,
-                storage_controller,
-                pageservers,
-                safekeepers,
-                control_plane_api,
-                control_plane_compute_hook_api,
-                branch_name_mappings,
-            } = on_disk_config;
-            LocalEnv {
-                base_data_dir: repopath.clone(),
-                pg_distrib_dir,
-                neon_distrib_dir,
-                default_tenant_id,
-                private_key_path,
-                broker,
-                storage_controller,
-                pageservers,
-                safekeepers,
-                control_plane_api,
-                control_plane_compute_hook_api,
-                branch_name_mappings,
-            }
-        };
+        let config = fs::read_to_string(repopath.join("config"))?;
+        let mut env: LocalEnv = toml::from_str(config.as_str())?;

-        // The source of truth for pageserver configuration is the pageserver.toml.
-        assert!(
-            env.pageservers.is_empty(),
-            "we ensure this during deserialization"
-        );
-        env.pageservers = {
-            let iter = std::fs::read_dir(&repopath).context("open dir")?;
-            let mut pageservers = Vec::new();
-            for res in iter {
-                let dentry = res?;
-                const PREFIX: &str = "pageserver_";
-                let dentry_name = dentry
-                    .file_name()
-                    .into_string()
-                    .ok()
-                    .with_context(|| format!("non-utf8 dentry: {:?}", dentry.path()))
-                    .unwrap();
-                if !dentry_name.starts_with(PREFIX) {
-                    continue;
-                }
-                if !dentry.file_type().context("determine file type")?.is_dir() {
-                    anyhow::bail!("expected a directory, got {:?}", dentry.path());
-                }
-                let id = dentry_name[PREFIX.len()..]
-                    .parse::<NodeId>()
-                    .with_context(|| format!("parse id from {:?}", dentry.path()))?;
-                // TODO(christian): use pageserver_api::config::ConfigToml (PR #7656)
-                #[derive(serde::Serialize, serde::Deserialize)]
-                // (allow unknown fields, unlike PageServerConf)
-                struct PageserverConfigTomlSubset {
-                    id: NodeId,
-                    listen_pg_addr: String,
-                    listen_http_addr: String,
-                    pg_auth_type: AuthType,
-                    http_auth_type: AuthType,
-                }
-                let config_toml_path = dentry.path().join("pageserver.toml");
-                let config_toml: PageserverConfigTomlSubset = toml_edit::de::from_str(
-                    &std::fs::read_to_string(&config_toml_path)
-                        .with_context(|| format!("read {:?}", config_toml_path))?,
-                )
-                .context("parse pageserver.toml")?;
-                let PageserverConfigTomlSubset {
-                    id: config_toml_id,
-                    listen_pg_addr,
-                    listen_http_addr,
-                    pg_auth_type,
-                    http_auth_type,
-                } = config_toml;
-                let conf = PageServerConf {
-                    id: {
-                        anyhow::ensure!(
-                            config_toml_id == id,
-                            "id mismatch: config_toml.id={config_toml_id} id={id}",
-                        );
-                        id
-                    },
-                    listen_pg_addr,
-                    listen_http_addr,
-                    pg_auth_type,
-                    http_auth_type,
-                };
-                pageservers.push(conf);
-            }
-            pageservers
-        };
+        env.base_data_dir = repopath;

        Ok(env)
    }

-    pub fn persist_config(&self) -> anyhow::Result<()> {
-        Self::persist_config_impl(
-            &self.base_data_dir,
-            &OnDiskConfig {
-                pg_distrib_dir: self.pg_distrib_dir.clone(),
-                neon_distrib_dir: self.neon_distrib_dir.clone(),
-                default_tenant_id: self.default_tenant_id,
-                private_key_path: self.private_key_path.clone(),
-                broker: self.broker.clone(),
-                storage_controller: self.storage_controller.clone(),
-                pageservers: vec![], // it's skip_serializing anyway
-                safekeepers: self.safekeepers.clone(),
-                control_plane_api: self.control_plane_api.clone(),
-                control_plane_compute_hook_api: self.control_plane_compute_hook_api.clone(),
-                branch_name_mappings: self.branch_name_mappings.clone(),
-            },
-        )
-    }
+    pub fn persist_config(&self, base_path: &Path) -> anyhow::Result<()> {
+        // Currently, the user first passes a config file with 'neon_local init --config=<path>'
+        // We read that in, in `create_config`, and fill any missing defaults. Then it's saved
+        // to .neon/config. TODO: We lose any formatting and comments along the way, which is
+        // a bit sad.
+        let mut conf_content = r#"# This file describes a local deployment of the page server
+# and safekeeeper node. It is read by the 'neon_local' command-line
+# utility.
+"#
+        .to_string();
+
+        // Convert the LocalEnv to a toml file.
+        //
+        // This could be as simple as this:
+        //
+        // conf_content += &toml::to_string_pretty(env)?;
+        //
+        // But it results in a "values must be emitted before tables". I'm not sure
+        // why, AFAICS the table, i.e. 'safekeepers: Vec<SafekeeperConf>' is last.
+        // Maybe rust reorders the fields to squeeze avoid padding or something?
+        // In any case, converting to toml::Value first, and serializing that, works.
+        // See https://github.com/alexcrichton/toml-rs/issues/142
+        conf_content += &toml::to_string_pretty(&toml::Value::try_from(self)?)?;

-    pub fn persist_config_impl(base_path: &Path, config: &OnDiskConfig) -> anyhow::Result<()> {
-        let conf_content = &toml::to_string_pretty(config)?;
        let target_config_path = base_path.join("config");
        fs::write(&target_config_path, conf_content).with_context(|| {
            format!(
@@ -587,13 +464,17 @@ impl LocalEnv {
        }
    }

-    /// Materialize the [`NeonLocalInitConf`] to disk. Called during [`neon_local init`].
-    pub fn init(conf: NeonLocalInitConf, force: &InitForceMode) -> anyhow::Result<()> {
-        let base_path = base_path();
-        assert_ne!(base_path, Path::new(""));
-        let base_path = &base_path;
+    //
+    // Initialize a new Neon repository
+    //
+    pub fn init(&mut self, pg_version: u32, force: &InitForceMode) -> anyhow::Result<()> {
+        // check if config already exists
+        let base_path = &self.base_data_dir;
+        ensure!(
+            base_path != Path::new(""),
+            "repository base path is missing"
+        );

-        // create base_path dir
        if base_path.exists() {
            match force {
                InitForceMode::MustNotExist => {
@@ -625,96 +506,70 @@ impl LocalEnv {
                }
            }
        }
+
+        if !self.pg_bin_dir(pg_version)?.join("postgres").exists() {
+            bail!(
+                "Can't find postgres binary at {}",
+                self.pg_bin_dir(pg_version)?.display()
+            );
+        }
+        for binary in ["pageserver", "safekeeper"] {
+            if !self.neon_distrib_dir.join(binary).exists() {
+                bail!(
+                    "Can't find binary '{binary}' in neon distrib dir '{}'",
+                    self.neon_distrib_dir.display()
+                );
+            }
+        }
+
        if !base_path.exists() {
            fs::create_dir(base_path)?;
        }

-        let NeonLocalInitConf {
-            pg_distrib_dir,
-            neon_distrib_dir,
-            default_tenant_id,
-            broker,
-            storage_controller,
-            pageservers,
-            safekeepers,
-            control_plane_api,
-            control_plane_compute_hook_api,
-        } = conf;
-
-        // Find postgres binaries.
-        // Follow POSTGRES_DISTRIB_DIR if set, otherwise look in "pg_install".
-        // Note that later in the code we assume, that distrib dirs follow the same pattern
-        // for all postgres versions.
-        let pg_distrib_dir = pg_distrib_dir.unwrap_or_else(|| {
-            if let Some(postgres_bin) = env::var_os("POSTGRES_DISTRIB_DIR") {
-                postgres_bin.into()
-            } else {
-                let cwd = env::current_dir().unwrap();
-                cwd.join("pg_install")
-            }
-        });
-
-        // Find neon binaries.
-        let neon_distrib_dir = neon_distrib_dir
-            .unwrap_or_else(|| env::current_exe().unwrap().parent().unwrap().to_owned());
-
        // Generate keypair for JWT.
        //
        // The keypair is only needed if authentication is enabled in any of the
        // components. For convenience, we generate the keypair even if authentication
        // is not enabled, so that you can easily enable it after the initialization
-        // step.
-        generate_auth_keys(
-            base_path.join("auth_private_key.pem").as_path(),
-            base_path.join("auth_public_key.pem").as_path(),
-        )
-        .context("generate auth keys")?;
-        let private_key_path = PathBuf::from("auth_private_key.pem");
-
-        // create the runtime type because the remaining initialization code below needs
-        // a LocalEnv instance op operation
-        // TODO: refactor to avoid this, LocalEnv should only be constructed from on-disk state
-        let env = LocalEnv {
-            base_data_dir: base_path.clone(),
-            pg_distrib_dir,
-            neon_distrib_dir,
-            default_tenant_id: Some(default_tenant_id),
-            private_key_path,
-            broker,
-            storage_controller: storage_controller.unwrap_or_default(),
-            pageservers: pageservers.iter().map(Into::into).collect(),
-            safekeepers,
-            control_plane_api: control_plane_api.unwrap_or_default(),
-            control_plane_compute_hook_api: control_plane_compute_hook_api.unwrap_or_default(),
-            branch_name_mappings: Default::default(),
-        };
-
-        // create endpoints dir
-        fs::create_dir_all(env.endpoints_path())?;
-
-        // create safekeeper dirs
-        for safekeeper in &env.safekeepers {
-            fs::create_dir_all(SafekeeperNode::datadir_path_by_id(&env, safekeeper.id))?;
+        // step. However, if the key generation fails, we treat it as non-fatal if
+        // authentication was not enabled.
+        if self.private_key_path == PathBuf::new() {
+            match generate_auth_keys(
+                base_path.join("auth_private_key.pem").as_path(),
+                base_path.join("auth_public_key.pem").as_path(),
+            ) {
+                Ok(()) => {
+                    self.private_key_path = PathBuf::from("auth_private_key.pem");
+                }
+                Err(e) => {
+                    if !self.auth_keys_needed() {
+                        eprintln!("Could not generate keypair for JWT authentication: {e}");
+                        eprintln!("Continuing anyway because authentication was not enabled");
+                        self.private_key_path = PathBuf::from("auth_private_key.pem");
+                    } else {
+                        return Err(e);
+                    }
+                }
+            }
        }

-        // initialize pageserver state
-        for (i, ps) in pageservers.into_iter().enumerate() {
-            let runtime_ps = &env.pageservers[i];
-            assert_eq!(&PageServerConf::from(&ps), runtime_ps);
-            fs::create_dir(env.pageserver_data_dir(ps.id))?;
-            PageServerNode::from_env(&env, runtime_ps)
-                .initialize(ps)
-                .context("pageserver init failed")?;
+        fs::create_dir_all(self.endpoints_path())?;
+
+        for safekeeper in &self.safekeepers {
+            fs::create_dir_all(SafekeeperNode::datadir_path_by_id(self, safekeeper.id))?;
        }

-        // setup remote remote location for default LocalFs remote storage
-        std::fs::create_dir_all(env.base_data_dir.join(PAGESERVER_REMOTE_STORAGE_DIR))?;
+        self.persist_config(base_path)
+    }

-        env.persist_config()
+    fn auth_keys_needed(&self) -> bool {
+        self.pageservers.iter().any(|ps| {
+            ps.pg_auth_type == AuthType::NeonJWT || ps.http_auth_type == AuthType::NeonJWT
+        }) || self.safekeepers.iter().any(|sk| sk.auth_enabled)
    }
 }

-pub fn base_path() -> PathBuf {
+fn base_path() -> PathBuf {
    match std::env::var_os("NEON_REPO_DIR") {
        Some(val) => PathBuf::from(val),
        None => PathBuf::from(".neon"),
@@ -757,3 +612,31 @@ fn generate_auth_keys(private_key_path: &Path, public_key_path: &Path) -> anyhow
    }
    Ok(())
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn simple_conf_parsing() {
+        let simple_conf_toml = include_str!("../simple.conf");
+        let simple_conf_parse_result = LocalEnv::parse_config(simple_conf_toml);
+        assert!(
+            simple_conf_parse_result.is_ok(),
+            "failed to parse simple config {simple_conf_toml}, reason: {simple_conf_parse_result:?}"
+        );
+
+        let string_to_replace = "listen_addr = '127.0.0.1:50051'";
+        let spoiled_url_str = "listen_addr = '!@$XOXO%^&'";
+        let spoiled_url_toml = simple_conf_toml.replace(string_to_replace, spoiled_url_str);
+        assert!(
+            spoiled_url_toml.contains(spoiled_url_str),
+            "Failed to replace string {string_to_replace} in the toml file {simple_conf_toml}"
+        );
+        let spoiled_url_parse_result = LocalEnv::parse_config(&spoiled_url_toml);
+        assert!(
+            spoiled_url_parse_result.is_err(),
+            "expected toml with invalid Url {spoiled_url_toml} to fail the parsing, but got {spoiled_url_parse_result:?}"
+        );
+    }
+}
--- a/control_plane/src/pageserver.rs
+++ b/control_plane/src/pageserver.rs
@@ -4,21 +4,21 @@
 //!
 //!   .neon/
 //!
+use std::borrow::Cow;
 use std::collections::HashMap;

 use std::io;
 use std::io::Write;
 use std::num::NonZeroU64;
 use std::path::PathBuf;
-use std::str::FromStr;
+use std::process::Command;
 use std::time::Duration;

 use anyhow::{bail, Context};
 use camino::Utf8PathBuf;
 use futures::SinkExt;
 use pageserver_api::models::{
-    self, AuxFilePolicy, LocationConfig, ShardParameters, TenantHistorySize, TenantInfo,
-    TimelineInfo,
+    self, LocationConfig, ShardParameters, TenantHistorySize, TenantInfo, TimelineInfo,
 };
 use pageserver_api::shard::TenantShardId;
 use pageserver_client::mgmt_api;
@@ -30,7 +30,7 @@ use utils::{
    lsn::Lsn,
 };

-use crate::local_env::{NeonLocalInitPageserverConf, PageServerConf};
+use crate::local_env::PageServerConf;
 use crate::{background_process, local_env::LocalEnv};

 /// Directory within .neon which will be used by default for LocalFs remote storage.
@@ -74,23 +74,71 @@ impl PageServerNode {
        }
    }

-    fn pageserver_init_make_toml(
-        &self,
-        conf: NeonLocalInitPageserverConf,
-    ) -> anyhow::Result<toml_edit::Document> {
-        assert_eq!(&PageServerConf::from(&conf), &self.conf, "during neon_local init, we derive the runtime state of ps conf (self.conf) from the --config flag fully");
-
-        // TODO(christian): instead of what we do here, create a pageserver_api::config::ConfigToml (PR #7656)
-
+    /// Merge overrides provided by the user on the command line with our default overides derived from neon_local configuration.
+    ///
+    /// These all end up on the command line of the `pageserver` binary.
+    fn neon_local_overrides(&self, cli_overrides: &[&str]) -> Vec<String> {
        // FIXME: the paths should be shell-escaped to handle paths with spaces, quotas etc.
        let pg_distrib_dir_param = format!(
            "pg_distrib_dir='{}'",
            self.env.pg_distrib_dir_raw().display()
        );

+        let PageServerConf {
+            id,
+            listen_pg_addr,
+            listen_http_addr,
+            pg_auth_type,
+            http_auth_type,
+            virtual_file_io_engine,
+            get_vectored_impl,
+            get_impl,
+            validate_vectored_get,
+        } = &self.conf;
+
+        let id = format!("id={}", id);
+
+        let http_auth_type_param = format!("http_auth_type='{}'", http_auth_type);
+        let listen_http_addr_param = format!("listen_http_addr='{}'", listen_http_addr);
+
+        let pg_auth_type_param = format!("pg_auth_type='{}'", pg_auth_type);
+        let listen_pg_addr_param = format!("listen_pg_addr='{}'", listen_pg_addr);
+        let virtual_file_io_engine = if let Some(virtual_file_io_engine) = virtual_file_io_engine {
+            format!("virtual_file_io_engine='{virtual_file_io_engine}'")
+        } else {
+            String::new()
+        };
+        let get_vectored_impl = if let Some(get_vectored_impl) = get_vectored_impl {
+            format!("get_vectored_impl='{get_vectored_impl}'")
+        } else {
+            String::new()
+        };
+        let get_impl = if let Some(get_impl) = get_impl {
+            format!("get_impl='{get_impl}'")
+        } else {
+            String::new()
+        };
+        let validate_vectored_get = if let Some(validate_vectored_get) = validate_vectored_get {
+            format!("validate_vectored_get={validate_vectored_get}")
+        } else {
+            String::new()
+        };
+
        let broker_endpoint_param = format!("broker_endpoint='{}'", self.env.broker.client_url());

-        let mut overrides = vec![pg_distrib_dir_param, broker_endpoint_param];
+        let mut overrides = vec![
+            id,
+            pg_distrib_dir_param,
+            http_auth_type_param,
+            pg_auth_type_param,
+            listen_http_addr_param,
+            listen_pg_addr_param,
+            broker_endpoint_param,
+            virtual_file_io_engine,
+            get_vectored_impl,
+            get_impl,
+            validate_vectored_get,
+        ];

        if let Some(control_plane_api) = &self.env.control_plane_api {
            overrides.push(format!(
@@ -100,7 +148,7 @@ impl PageServerNode {

            // Storage controller uses the same auth as pageserver: if JWT is enabled
            // for us, we will also need it to talk to them.
-            if matches!(conf.http_auth_type, AuthType::NeonJWT) {
+            if matches!(http_auth_type, AuthType::NeonJWT) {
                let jwt_token = self
                    .env
                    .generate_auth_token(&Claims::new(None, Scope::GenerationsApi))
@@ -109,40 +157,31 @@ impl PageServerNode {
            }
        }

-        if !conf.other.contains_key("remote_storage") {
+        if !cli_overrides
+            .iter()
+            .any(|c| c.starts_with("remote_storage"))
+        {
            overrides.push(format!(
                "remote_storage={{local_path='../{PAGESERVER_REMOTE_STORAGE_DIR}'}}"
            ));
        }

-        if conf.http_auth_type != AuthType::Trust || conf.pg_auth_type != AuthType::Trust {
+        if *http_auth_type != AuthType::Trust || *pg_auth_type != AuthType::Trust {
            // Keys are generated in the toplevel repo dir, pageservers' workdirs
            // are one level below that, so refer to keys with ../
            overrides.push("auth_validation_public_key_path='../auth_public_key.pem'".to_owned());
        }

        // Apply the user-provided overrides
-        overrides.push(
-            toml_edit::ser::to_string_pretty(&conf)
-                .expect("we deserialized this from toml earlier"),
-        );
+        overrides.extend(cli_overrides.iter().map(|&c| c.to_owned()));

-        // Turn `overrides` into a toml document.
-        // TODO: above code is legacy code, it should be refactored to use toml_edit directly.
-        let mut config_toml = toml_edit::Document::new();
-        for fragment_str in overrides {
-            let fragment = toml_edit::Document::from_str(&fragment_str)
-                .expect("all fragments in `overrides` are valid toml documents, this function controls that");
-            for (key, item) in fragment.iter() {
-                config_toml.insert(key, item.clone());
-            }
-        }
-        Ok(config_toml)
+        overrides
    }

    /// Initializes a pageserver node by creating its config with the overrides provided.
-    pub fn initialize(&self, conf: NeonLocalInitPageserverConf) -> anyhow::Result<()> {
-        self.pageserver_init(conf)
+    pub fn initialize(&self, config_overrides: &[&str]) -> anyhow::Result<()> {
+        // First, run `pageserver --init` and wait for it to write a config into FS and exit.
+        self.pageserver_init(config_overrides)
            .with_context(|| format!("Failed to run init for pageserver node {}", self.conf.id))
    }

@@ -158,11 +197,11 @@ impl PageServerNode {
            .expect("non-Unicode path")
    }

-    pub async fn start(&self) -> anyhow::Result<()> {
-        self.start_node().await
+    pub async fn start(&self, config_overrides: &[&str]) -> anyhow::Result<()> {
+        self.start_node(config_overrides, false).await
    }

-    fn pageserver_init(&self, conf: NeonLocalInitPageserverConf) -> anyhow::Result<()> {
+    fn pageserver_init(&self, config_overrides: &[&str]) -> anyhow::Result<()> {
        let datadir = self.repo_path();
        let node_id = self.conf.id;
        println!(
@@ -173,20 +212,29 @@ impl PageServerNode {
        );
        io::stdout().flush()?;

-        let config = self
-            .pageserver_init_make_toml(conf)
-            .context("make pageserver toml")?;
-        let config_file_path = datadir.join("pageserver.toml");
-        let mut config_file = std::fs::OpenOptions::new()
-            .create_new(true)
-            .write(true)
-            .open(&config_file_path)
-            .with_context(|| format!("open pageserver toml for write: {config_file_path:?}"))?;
-        config_file
-            .write_all(config.to_string().as_bytes())
-            .context("write pageserver toml")?;
-        drop(config_file);
-        // TODO: invoke a TBD config-check command to validate that pageserver will start with the written config
+        if !datadir.exists() {
+            std::fs::create_dir(&datadir)?;
+        }
+
+        let datadir_path_str = datadir.to_str().with_context(|| {
+            format!("Cannot start pageserver node {node_id} in path that has no string representation: {datadir:?}")
+        })?;
+        let mut args = self.pageserver_basic_args(config_overrides, datadir_path_str);
+        args.push(Cow::Borrowed("--init"));
+
+        let init_output = Command::new(self.env.pageserver_bin())
+            .args(args.iter().map(Cow::as_ref))
+            .envs(self.pageserver_env_variables()?)
+            .output()
+            .with_context(|| format!("Failed to run pageserver init for node {node_id}"))?;
+
+        anyhow::ensure!(
+            init_output.status.success(),
+            "Pageserver init for node {} did not finish successfully, stdout: {}, stderr: {}",
+            node_id,
+            String::from_utf8_lossy(&init_output.stdout),
+            String::from_utf8_lossy(&init_output.stderr),
+        );

        // Write metadata file, used by pageserver on startup to register itself with
        // the storage controller
@@ -200,13 +248,12 @@ impl PageServerNode {
        // situation: the metadata is written by some other script.
        std::fs::write(
            metadata_path,
-            serde_json::to_vec(&pageserver_api::config::NodeMetadata {
-                postgres_host: "localhost".to_string(),
-                postgres_port: self.pg_connection_config.port(),
-                http_host: "localhost".to_string(),
-                http_port,
-                other: HashMap::new(),
-            })
+            serde_json::to_vec(&serde_json::json!({
+                "host": "localhost",
+                "port": self.pg_connection_config.port(),
+                "http_host": "localhost",
+                "http_port": http_port,
+            }))
            .unwrap(),
        )
        .expect("Failed to write metadata file");
@@ -214,7 +261,11 @@ impl PageServerNode {
        Ok(())
    }

-    async fn start_node(&self) -> anyhow::Result<()> {
+    async fn start_node(
+        &self,
+        config_overrides: &[&str],
+        update_config: bool,
+    ) -> anyhow::Result<()> {
        // TODO: using a thread here because start_process() is not async but we need to call check_status()
        let datadir = self.repo_path();
        print!(
@@ -231,12 +282,15 @@ impl PageServerNode {
                self.conf.id, datadir,
            )
        })?;
-        let args = vec!["-D", datadir_path_str];
+        let mut args = self.pageserver_basic_args(config_overrides, datadir_path_str);
+        if update_config {
+            args.push(Cow::Borrowed("--update-config"));
+        }
        background_process::start_process(
            "pageserver",
            &datadir,
            &self.env.pageserver_bin(),
-            args,
+            args.iter().map(Cow::as_ref),
            self.pageserver_env_variables()?,
            background_process::InitialPidFile::Expect(self.pid_file()),
            || async {
@@ -253,6 +307,22 @@ impl PageServerNode {
        Ok(())
    }

+    fn pageserver_basic_args<'a>(
+        &self,
+        config_overrides: &'a [&'a str],
+        datadir_path_str: &'a str,
+    ) -> Vec<Cow<'a, str>> {
+        let mut args = vec![Cow::Borrowed("-D"), Cow::Borrowed(datadir_path_str)];
+
+        let overrides = self.neon_local_overrides(config_overrides);
+        for config_override in overrides {
+            args.push(Cow::Borrowed("-c"));
+            args.push(Cow::Owned(config_override));
+        }
+
+        args
+    }
+
    fn pageserver_env_variables(&self) -> anyhow::Result<Vec<(String, String)>> {
        // FIXME: why is this tied to pageserver's auth type? Whether or not the safekeeper
        // needs a token, and how to generate that token, seems independent to whether
@@ -378,11 +448,11 @@ impl PageServerNode {
                .map(serde_json::from_str)
                .transpose()
                .context("parse `timeline_get_throttle` from json")?,
-            switch_aux_file_policy: settings
-                .remove("switch_aux_file_policy")
-                .map(|x| x.parse::<AuxFilePolicy>())
+            switch_to_aux_file_v2: settings
+                .remove("switch_to_aux_file_v2")
+                .map(|x| x.parse::<bool>())
                .transpose()
-                .context("Failed to parse 'switch_aux_file_policy'")?,
+                .context("Failed to parse 'switch_to_aux_file_v2' as bool")?,
        };
        if !settings.is_empty() {
            bail!("Unrecognized tenant settings: {settings:?}")
@@ -501,11 +571,11 @@ impl PageServerNode {
                    .map(serde_json::from_str)
                    .transpose()
                    .context("parse `timeline_get_throttle` from json")?,
-                switch_aux_file_policy: settings
-                    .remove("switch_aux_file_policy")
-                    .map(|x| x.parse::<AuxFilePolicy>())
+                switch_to_aux_file_v2: settings
+                    .remove("switch_to_aux_file_v2")
+                    .map(|x| x.parse::<bool>())
                    .transpose()
-                    .context("Failed to parse 'switch_aux_file_policy'")?,
+                    .context("Failed to parse 'switch_to_aux_file_v2' as bool")?,
            }
        };

--- a/control_plane/src/storage_controller.rs
+++ b/control_plane/src/storage_controller.rs
@@ -3,6 +3,7 @@ use crate::{
    local_env::{LocalEnv, NeonStorageControllerConf},
 };
 use camino::{Utf8Path, Utf8PathBuf};
+use hyper::Method;
 use pageserver_api::{
    controller_api::{
        NodeConfigureRequest, NodeRegisterRequest, TenantCreateResponse, TenantLocateResponse,
@@ -16,7 +17,6 @@ use pageserver_api::{
 };
 use pageserver_client::mgmt_api::ResponseErrorMessageExt;
 use postgres_backend::AuthType;
-use reqwest::Method;
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
 use std::{fs, str::FromStr};
 use tokio::process::Command;
@@ -379,7 +379,7 @@ impl StorageController {
    /// Simple HTTP request wrapper for calling into storage controller
    async fn dispatch<RQ, RS>(
        &self,
-        method: reqwest::Method,
+        method: hyper::Method,
        path: String,
        body: Option<RQ>,
    ) -> anyhow::Result<RS>
--- a/control_plane/storcon_cli/src/main.rs
+++ b/control_plane/storcon_cli/src/main.rs
@@ -1,6 +1,7 @@
 use std::{collections::HashMap, str::FromStr, time::Duration};

 use clap::{Parser, Subcommand};
+use hyper::{Method, StatusCode};
 use pageserver_api::{
    controller_api::{
        NodeAvailabilityWrapper, NodeDescribeResponse, ShardSchedulingPolicy,
@@ -13,7 +14,7 @@ use pageserver_api::{
    shard::{ShardStripeSize, TenantShardId},
 };
 use pageserver_client::mgmt_api::{self, ResponseErrorMessageExt};
-use reqwest::{Method, StatusCode, Url};
+use reqwest::Url;
 use serde::{de::DeserializeOwned, Serialize};
 use utils::id::{NodeId, TenantId};

@@ -231,7 +232,7 @@ impl Client {
    /// Simple HTTP request wrapper for calling into storage controller
    async fn dispatch<RQ, RS>(
        &self,
-        method: Method,
+        method: hyper::Method,
        path: String,
        body: Option<RQ>,
    ) -> mgmt_api::Result<RS>
--- a/libs/compute_api/src/spec.rs
+++ b/libs/compute_api/src/spec.rs
@@ -33,23 +33,6 @@ pub struct ComputeSpec {
    #[serde(default)]
    pub features: Vec<ComputeFeature>,

-    /// If compute_ctl was passed `--resize-swap-on-bind`, a value of `Some(_)` instructs
-    /// compute_ctl to `/neonvm/bin/resize-swap` with the given size, when the spec is first
-    /// received.
-    ///
-    /// Both this field and `--resize-swap-on-bind` are required, so that the control plane's
-    /// spec generation doesn't need to be aware of the actual compute it's running on, while
-    /// guaranteeing gradual rollout of swap. Otherwise, without `--resize-swap-on-bind`, we could
-    /// end up trying to resize swap in VMs without it -- or end up *not* resizing swap, thus
-    /// giving every VM much more swap than it should have (32GiB).
-    ///
-    /// Eventually we may remove `--resize-swap-on-bind` and exclusively use `swap_size_bytes` for
-    /// enabling the swap resizing behavior once rollout is complete.
-    ///
-    /// See neondatabase/cloud#12047 for more.
-    #[serde(default)]
-    pub swap_size_bytes: Option<u64>,
-
    /// Expected cluster state at the end of transition process.
    pub cluster: Cluster,
    pub delta_operations: Option<Vec<DeltaOp>>,
--- a/libs/metrics/src/lib.rs
+++ b/libs/metrics/src/lib.rs
@@ -480,15 +480,6 @@ impl<A: CounterPairAssoc> CounterPairVec<A> {
        let id = self.vec.with_labels(labels);
        self.vec.remove_metric(id)
    }
-
-    pub fn sample(&self, labels: <A::LabelGroupSet as LabelGroupSet>::Group<'_>) -> u64 {
-        let id = self.vec.with_labels(labels);
-        let metric = self.vec.get_metric(id);
-
-        let inc = metric.inc.count.load(std::sync::atomic::Ordering::Relaxed);
-        let dec = metric.dec.count.load(std::sync::atomic::Ordering::Relaxed);
-        inc.saturating_sub(dec)
-    }
 }

 impl<T, A> ::measured::metric::group::MetricGroup<T> for CounterPairVec<A>
--- a/libs/pageserver_api/src/config.rs
+++ b/libs/pageserver_api/src/config.rs
@@ -1,31 +0,0 @@
-use std::collections::HashMap;
-
-use const_format::formatcp;
-
-#[cfg(test)]
-mod tests;
-
-pub const DEFAULT_PG_LISTEN_PORT: u16 = 64000;
-pub const DEFAULT_PG_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_PG_LISTEN_PORT}");
-pub const DEFAULT_HTTP_LISTEN_PORT: u16 = 9898;
-pub const DEFAULT_HTTP_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_HTTP_LISTEN_PORT}");
-
-// Certain metadata (e.g. externally-addressable name, AZ) is delivered
-// as a separate structure.  This information is not neeed by the pageserver
-// itself, it is only used for registering the pageserver with the control
-// plane and/or storage controller.
-//
-#[derive(PartialEq, Eq, Debug, serde::Serialize, serde::Deserialize)]
-pub struct NodeMetadata {
-    #[serde(rename = "host")]
-    pub postgres_host: String,
-    #[serde(rename = "port")]
-    pub postgres_port: u16,
-    pub http_host: String,
-    pub http_port: u16,
-
-    // Deployment tools may write fields to the metadata file beyond what we
-    // use in this type: this type intentionally only names fields that require.
-    #[serde(flatten)]
-    pub other: HashMap<String, serde_json::Value>,
-}
--- a/libs/pageserver_api/src/config/tests.rs
+++ b/libs/pageserver_api/src/config/tests.rs
@@ -1,22 +0,0 @@
-use super::*;
-
-#[test]
-fn test_node_metadata_v1_backward_compatibilty() {
-    let v1 = serde_json::to_vec(&serde_json::json!({
-        "host": "localhost",
-        "port": 23,
-        "http_host": "localhost",
-        "http_port": 42,
-    }));
-
-    assert_eq!(
-        serde_json::from_slice::<NodeMetadata>(&v1.unwrap()).unwrap(),
-        NodeMetadata {
-            postgres_host: "localhost".to_string(),
-            postgres_port: 23,
-            http_host: "localhost".to_string(),
-            http_port: 42,
-            other: HashMap::new(),
-        }
-    )
-}
--- a/libs/pageserver_api/src/key.rs
+++ b/libs/pageserver_api/src/key.rs
@@ -80,7 +80,7 @@ impl Key {
    }

    /// Get the range of metadata keys.
-    pub const fn metadata_key_range() -> Range<Self> {
+    pub fn metadata_key_range() -> Range<Self> {
        Key {
            field1: METADATA_KEY_BEGIN_PREFIX,
            field2: 0,
@@ -572,17 +572,14 @@ pub const AUX_FILES_KEY: Key = Key {
 // Reverse mappings for a few Keys.
 // These are needed by WAL redo manager.

-/// Non inherited range for vectored get.
 pub const NON_INHERITED_RANGE: Range<Key> = AUX_FILES_KEY..AUX_FILES_KEY.next();
-/// Sparse keyspace range for vectored get. Missing key error will be ignored for this range.
-pub const NON_INHERITED_SPARSE_RANGE: Range<Key> = Key::metadata_key_range();

 // AUX_FILES currently stores only data for logical replication (slots etc), and
 // we don't preserve these on a branch because safekeepers can't follow timeline
 // switch (and generally it likely should be optional), so ignore these.
 #[inline(always)]
 pub fn is_inherited_key(key: Key) -> bool {
-    !NON_INHERITED_RANGE.contains(&key) && !NON_INHERITED_SPARSE_RANGE.contains(&key)
+    !NON_INHERITED_RANGE.contains(&key)
 }

 #[inline(always)]
--- a/libs/pageserver_api/src/keyspace.rs
+++ b/libs/pageserver_api/src/keyspace.rs
@@ -240,7 +240,7 @@ impl<'a> ShardedRange<'a> {
    /// pages that would not actually be stored on this node.
    ///
    /// Don't use this function in code that works with physical entities like layer files.
-    pub fn raw_size(range: &Range<Key>) -> u32 {
+    fn raw_size(range: &Range<Key>) -> u32 {
        if is_contiguous_range(range) {
            contiguous_range_len(range)
        } else {
--- a/libs/pageserver_api/src/lib.rs
+++ b/libs/pageserver_api/src/lib.rs
@@ -1,5 +1,6 @@
 #![deny(unsafe_code)]
 #![deny(clippy::undocumented_unsafe_blocks)]
+use const_format::formatcp;

 pub mod controller_api;
 pub mod key;
@@ -10,4 +11,7 @@ pub mod shard;
 /// Public API types
 pub mod upcall_api;

-pub mod config;
+pub const DEFAULT_PG_LISTEN_PORT: u16 = 64000;
+pub const DEFAULT_PG_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_PG_LISTEN_PORT}");
+pub const DEFAULT_HTTP_LISTEN_PORT: u16 = 9898;
+pub const DEFAULT_HTTP_LISTEN_ADDR: &str = formatcp!("127.0.0.1:{DEFAULT_HTTP_LISTEN_PORT}");
--- a/libs/pageserver_api/src/models.rs
+++ b/libs/pageserver_api/src/models.rs
@@ -1,4 +1,3 @@
-pub mod detach_ancestor;
 pub mod partitioning;
 pub mod utilization;

@@ -9,7 +8,6 @@ use std::{
    collections::HashMap,
    io::{BufRead, Read},
    num::{NonZeroU64, NonZeroUsize},
-    str::FromStr,
    time::{Duration, SystemTime},
 };

@@ -305,31 +303,7 @@ pub struct TenantConfig {
    pub lazy_slru_download: Option<bool>,
    pub timeline_get_throttle: Option<ThrottleConfig>,
    pub image_layer_creation_check_threshold: Option<u8>,
-    pub switch_aux_file_policy: Option<AuxFilePolicy>,
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
-pub enum AuxFilePolicy {
-    V1,
-    V2,
-    CrossValidation,
-}
-
-impl FromStr for AuxFilePolicy {
-    type Err = anyhow::Error;
-
-    fn from_str(s: &str) -> Result<Self, Self::Err> {
-        let s = s.to_lowercase();
-        if s == "v1" {
-            Ok(Self::V1)
-        } else if s == "v2" {
-            Ok(Self::V2)
-        } else if s == "crossvalidation" || s == "cross_validation" {
-            Ok(Self::CrossValidation)
-        } else {
-            anyhow::bail!("cannot parse {} to aux file policy", s)
-        }
-    }
+    pub switch_to_aux_file_v2: Option<bool>,
 }

 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
@@ -456,6 +430,8 @@ pub struct StatusResponse {
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(deny_unknown_fields)]
 pub struct TenantLocationConfigRequest {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub tenant_id: Option<TenantShardId>,
    #[serde(flatten)]
    pub config: LocationConfig, // as we have a flattened field, we should reject all unknown fields in it
 }
--- a/libs/pageserver_api/src/models/detach_ancestor.rs
+++ b/libs/pageserver_api/src/models/detach_ancestor.rs
@@ -1,6 +0,0 @@
-use utils::id::TimelineId;
-
-#[derive(Default, serde::Serialize)]
-pub struct AncestorDetached {
-    pub reparented_timelines: Vec<TimelineId>,
-}
--- a/libs/pageserver_api/src/shard.rs
+++ b/libs/pageserver_api/src/shard.rs
@@ -97,7 +97,7 @@ impl ShardCount {

    /// The internal value of a ShardCount may be zero, which means "1 shard, but use
    /// legacy format for TenantShardId that excludes the shard suffix", also known
-    /// as [`TenantShardId::unsharded`].
+    /// as `TenantShardId::unsharded`.
    ///
    /// This method returns the actual number of shards, i.e. if our internal value is
    /// zero, we return 1 (unsharded tenants have 1 shard).
@@ -116,9 +116,7 @@ impl ShardCount {
        self.0
    }

-    /// Whether the `ShardCount` is for an unsharded tenant, so uses one shard but
-    /// uses the legacy format for `TenantShardId`. See also the documentation for
-    /// [`Self::count`].
+    ///
    pub fn is_unsharded(&self) -> bool {
        self.0 == 0
    }
--- a/libs/postgres_ffi/src/xlog_utils.rs
+++ b/libs/postgres_ffi/src/xlog_utils.rs
@@ -331,10 +331,7 @@ impl CheckPoint {
    /// Returns 'true' if the XID was updated.
    pub fn update_next_xid(&mut self, xid: u32) -> bool {
        // nextXid should be greater than any XID in WAL, so increment provided XID and check for wraparround.
-        let mut new_xid = std::cmp::max(
-            xid.wrapping_add(1),
-            pg_constants::FIRST_NORMAL_TRANSACTION_ID,
-        );
+        let mut new_xid = std::cmp::max(xid.wrapping_add(1), pg_constants::FIRST_NORMAL_TRANSACTION_ID);
        // To reduce number of metadata checkpoints, we forward align XID on XID_CHECKPOINT_INTERVAL.
        // XID_CHECKPOINT_INTERVAL should not be larger than BLCKSZ*CLOG_XACTS_PER_BYTE
        new_xid =
@@ -370,16 +367,8 @@ pub fn generate_wal_segment(segno: u64, system_id: u64, lsn: Lsn) -> Result<Byte
    let seg_off = lsn.segment_offset(WAL_SEGMENT_SIZE);

    let first_page_only = seg_off < XLOG_BLCKSZ;
-    // If first records starts in the middle of the page, pretend in page header
-    // there is a fake record which ends where first real record starts. This
-    // makes pg_waldump etc happy.
-    let (shdr_rem_len, infoflags) = if first_page_only && seg_off > 0 {
-        assert!(seg_off >= XLOG_SIZE_OF_XLOG_LONG_PHD);
-        // xlp_rem_len doesn't include page header, hence the subtraction.
-        (
-            seg_off - XLOG_SIZE_OF_XLOG_LONG_PHD,
-            pg_constants::XLP_FIRST_IS_CONTRECORD,
-        )
+    let (shdr_rem_len, infoflags) = if first_page_only {
+        (seg_off, pg_constants::XLP_FIRST_IS_CONTRECORD)
    } else {
        (0, 0)
    };
@@ -408,22 +397,20 @@ pub fn generate_wal_segment(segno: u64, system_id: u64, lsn: Lsn) -> Result<Byte

    if !first_page_only {
        let block_offset = lsn.page_offset_in_segment(WAL_SEGMENT_SIZE) as usize;
-        // see comments above about XLP_FIRST_IS_CONTRECORD and xlp_rem_len.
-        let (xlp_rem_len, xlp_info) = if page_off > 0 {
-            assert!(page_off >= XLOG_SIZE_OF_XLOG_SHORT_PHD as u64);
-            (
-                (page_off - XLOG_SIZE_OF_XLOG_SHORT_PHD as u64) as u32,
-                pg_constants::XLP_FIRST_IS_CONTRECORD,
-            )
-        } else {
-            (0, 0)
-        };
        let header = XLogPageHeaderData {
            xlp_magic: XLOG_PAGE_MAGIC as u16,
-            xlp_info,
+            xlp_info: if page_off >= pg_constants::SIZE_OF_PAGE_HEADER as u64 {
+                pg_constants::XLP_FIRST_IS_CONTRECORD
+            } else {
+                0
+            },
            xlp_tli: PG_TLI,
            xlp_pageaddr: lsn.page_lsn().0,
-            xlp_rem_len,
+            xlp_rem_len: if page_off >= pg_constants::SIZE_OF_PAGE_HEADER as u64 {
+                page_off as u32
+            } else {
+                0u32
+            },
            ..Default::default() // Put 0 in padding fields.
        };
        let hdr_bytes = header.encode()?;
--- a/libs/remote_storage/Cargo.toml
+++ b/libs/remote_storage/Cargo.toml
@@ -38,7 +38,6 @@ azure_storage_blobs.workspace = true
 futures-util.workspace = true
 http-types.workspace = true
 itertools.workspace = true
-sync_wrapper = { workspace = true, features = ["futures"] }

 [dev-dependencies]
 camino-tempfile.workspace = true
--- a/libs/remote_storage/src/azure_blob.rs
+++ b/libs/remote_storage/src/azure_blob.rs
@@ -3,7 +3,6 @@
 use std::borrow::Cow;
 use std::collections::HashMap;
 use std::env;
-use std::io;
 use std::num::NonZeroU32;
 use std::pin::Pin;
 use std::str::FromStr;
@@ -21,7 +20,6 @@ use azure_storage_blobs::blob::CopyStatus;
 use azure_storage_blobs::prelude::ClientBuilder;
 use azure_storage_blobs::{blob::operations::GetBlobBuilder, prelude::ContainerClient};
 use bytes::Bytes;
-use futures::future::Either;
 use futures::stream::Stream;
 use futures_util::StreamExt;
 use futures_util::TryStreamExt;
@@ -130,12 +128,12 @@ impl AzureBlobStorage {
        let kind = RequestKind::Get;

        let _permit = self.permit(kind, cancel).await?;
-        let cancel_or_timeout = crate::support::cancel_or_timeout(self.timeout, cancel.clone());
-        let cancel_or_timeout_ = crate::support::cancel_or_timeout(self.timeout, cancel.clone());

        let mut etag = None;
        let mut last_modified = None;
        let mut metadata = HashMap::new();
+        // TODO give proper streaming response instead of buffering into RAM
+        // https://github.com/neondatabase/neon/issues/5563

        let download = async {
            let response = builder
@@ -154,46 +152,39 @@ impl AzureBlobStorage {
                Err(_elapsed) => Err(DownloadError::Timeout),
            });

-            let mut response = Box::pin(response);
+            let mut response = std::pin::pin!(response);

-            let Some(part) = response.next().await else {
+            let mut bufs = Vec::new();
+            while let Some(part) = response.next().await {
+                let part = part?;
+                if etag.is_none() {
+                    etag = Some(part.blob.properties.etag);
+                }
+                if last_modified.is_none() {
+                    last_modified = Some(part.blob.properties.last_modified.into());
+                }
+                if let Some(blob_meta) = part.blob.metadata {
+                    metadata.extend(blob_meta.iter().map(|(k, v)| (k.to_owned(), v.to_owned())));
+                }
+                let data = part
+                    .data
+                    .collect()
+                    .await
+                    .map_err(|e| DownloadError::Other(e.into()))?;
+                bufs.push(data);
+            }
+
+            if bufs.is_empty() {
                return Err(DownloadError::Other(anyhow::anyhow!(
-                    "Azure GET response contained no response body"
+                    "Azure GET response contained no buffers"
                )));
-            };
-            let part = part?;
-            if etag.is_none() {
-                etag = Some(part.blob.properties.etag);
            }
-            if last_modified.is_none() {
-                last_modified = Some(part.blob.properties.last_modified.into());
-            }
-            if let Some(blob_meta) = part.blob.metadata {
-                metadata.extend(blob_meta.iter().map(|(k, v)| (k.to_owned(), v.to_owned())));
-            }
-
            // unwrap safety: if these were None, bufs would be empty and we would have returned an error already
            let etag = etag.unwrap();
            let last_modified = last_modified.unwrap();

-            let tail_stream = response
-                .map(|part| match part {
-                    Ok(part) => Either::Left(part.data.map(|r| r.map_err(io::Error::other))),
-                    Err(e) => {
-                        Either::Right(futures::stream::once(async { Err(io::Error::other(e)) }))
-                    }
-                })
-                .flatten();
-            let stream = part
-                .data
-                .map(|r| r.map_err(io::Error::other))
-                .chain(sync_wrapper::SyncStream::new(tail_stream));
-            //.chain(SyncStream::from_pin(Box::pin(tail_stream)));
-
-            let download_stream = crate::support::DownloadStream::new(cancel_or_timeout_, stream);
-
            Ok(Download {
-                download_stream: Box::pin(download_stream),
+                download_stream: Box::pin(futures::stream::iter(bufs.into_iter().map(Ok))),
                etag,
                last_modified,
                metadata: Some(StorageMetadata(metadata)),
@@ -202,10 +193,7 @@ impl AzureBlobStorage {

        tokio::select! {
            bufs = download => bufs,
-            cancel_or_timeout = cancel_or_timeout => match cancel_or_timeout {
-                TimeoutOrCancel::Timeout => Err(DownloadError::Timeout),
-                TimeoutOrCancel::Cancel => Err(DownloadError::Cancelled),
-            },
+            _ = cancel.cancelled() => Err(DownloadError::Cancelled),
        }
    }

--- a/libs/remote_storage/src/lib.rs
+++ b/libs/remote_storage/src/lib.rs
@@ -55,11 +55,11 @@ pub use error::{DownloadError, TimeTravelError, TimeoutOrCancel};
 /// ~3500 PUT/COPY/POST/DELETE or 5500 GET/HEAD S3 requests
 /// <https://aws.amazon.com/premiumsupport/knowledge-center/s3-request-limit-avoid-throttling/>
 pub const DEFAULT_REMOTE_STORAGE_S3_CONCURRENCY_LIMIT: usize = 100;
-/// Set this limit analogously to the S3 limit
+/// We set this a little bit low as we currently buffer the entire file into RAM
 ///
 /// Here, a limit of max 20k concurrent connections was noted.
 /// <https://learn.microsoft.com/en-us/answers/questions/1301863/is-there-any-limitation-to-concurrent-connections>
-pub const DEFAULT_REMOTE_STORAGE_AZURE_CONCURRENCY_LIMIT: usize = 100;
+pub const DEFAULT_REMOTE_STORAGE_AZURE_CONCURRENCY_LIMIT: usize = 30;
 /// No limits on the client side, which currenltly means 1000 for AWS S3.
 /// <https://docs.aws.amazon.com/AmazonS3/latest/API/API_ListObjectsV2.html#API_ListObjectsV2_RequestSyntax>
 pub const DEFAULT_MAX_KEYS_PER_LIST_RESPONSE: Option<i32> = None;
--- a/libs/remote_storage/src/s3_bucket.rs
+++ b/libs/remote_storage/src/s3_bucket.rs
@@ -27,7 +27,7 @@ use aws_config::{
 };
 use aws_credential_types::provider::SharedCredentialsProvider;
 use aws_sdk_s3::{
-    config::{AsyncSleep, IdentityCache, Region, SharedAsyncSleep},
+    config::{AsyncSleep, Builder, IdentityCache, Region, SharedAsyncSleep},
    error::SdkError,
    operation::get_object::GetObjectError,
    types::{Delete, DeleteMarkerEntry, ObjectIdentifier, ObjectVersion, StorageClass},
@@ -75,13 +75,13 @@ struct GetObjectRequest {
 }
 impl S3Bucket {
    /// Creates the S3 storage, errors if incorrect AWS S3 configuration provided.
-    pub fn new(remote_storage_config: &S3Config, timeout: Duration) -> anyhow::Result<Self> {
+    pub fn new(aws_config: &S3Config, timeout: Duration) -> anyhow::Result<Self> {
        tracing::debug!(
            "Creating s3 remote storage for S3 bucket {}",
-            remote_storage_config.bucket_name
+            aws_config.bucket_name
        );

-        let region = Some(Region::new(remote_storage_config.bucket_region.clone()));
+        let region = Some(Region::new(aws_config.bucket_region.clone()));

        let provider_conf = ProviderConfig::without_region().with_region(region.clone());

@@ -113,38 +113,6 @@ impl S3Bucket {
        // AWS SDK requires us to specify how the RetryConfig should sleep when it wants to back off
        let sleep_impl: Arc<dyn AsyncSleep> = Arc::new(TokioSleep::new());

-        let sdk_config_loader: aws_config::ConfigLoader = aws_config::defaults(
-            #[allow(deprecated)] /* TODO: https://github.com/neondatabase/neon/issues/7665 */
-            BehaviorVersion::v2023_11_09(),
-        )
-        .region(region)
-        .identity_cache(IdentityCache::lazy().build())
-        .credentials_provider(SharedCredentialsProvider::new(credentials_provider))
-        .sleep_impl(SharedAsyncSleep::from(sleep_impl));
-
-        let sdk_config: aws_config::SdkConfig = std::thread::scope(|s| {
-            s.spawn(|| {
-                // TODO: make this function async.
-                tokio::runtime::Builder::new_current_thread()
-                    .enable_all()
-                    .build()
-                    .unwrap()
-                    .block_on(sdk_config_loader.load())
-            })
-            .join()
-            .unwrap()
-        });
-
-        let mut s3_config_builder = aws_sdk_s3::config::Builder::from(&sdk_config);
-
-        // Technically, the `remote_storage_config.endpoint` field only applies to S3 interactions.
-        // (In case we ever re-use the `sdk_config` for more than just the S3 client in the future)
-        if let Some(custom_endpoint) = remote_storage_config.endpoint.clone() {
-            s3_config_builder = s3_config_builder
-                .endpoint_url(custom_endpoint)
-                .force_path_style(true);
-        }
-
        // We do our own retries (see [`backoff::retry`]).  However, for the AWS SDK to enable rate limiting in response to throttling
        // responses (e.g. 429 on too many ListObjectsv2 requests), we must provide a retry config.  We set it to use at most one
        // attempt, and enable 'Adaptive' mode, which causes rate limiting to be enabled.
@@ -152,36 +120,42 @@ impl S3Bucket {
        retry_config
            .set_max_attempts(Some(1))
            .set_mode(Some(RetryMode::Adaptive));
-        s3_config_builder = s3_config_builder.retry_config(retry_config.build());

-        let s3_config = s3_config_builder.build();
-        let client = aws_sdk_s3::Client::from_conf(s3_config);
+        let mut config_builder = Builder::default()
+            .behavior_version(BehaviorVersion::v2023_11_09())
+            .region(region)
+            .identity_cache(IdentityCache::lazy().build())
+            .credentials_provider(SharedCredentialsProvider::new(credentials_provider))
+            .retry_config(retry_config.build())
+            .sleep_impl(SharedAsyncSleep::from(sleep_impl));

-        let prefix_in_bucket = remote_storage_config
-            .prefix_in_bucket
-            .as_deref()
-            .map(|prefix| {
-                let mut prefix = prefix;
-                while prefix.starts_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
-                    prefix = &prefix[1..]
-                }
+        if let Some(custom_endpoint) = aws_config.endpoint.clone() {
+            config_builder = config_builder
+                .endpoint_url(custom_endpoint)
+                .force_path_style(true);
+        }

-                let mut prefix = prefix.to_string();
-                while prefix.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
-                    prefix.pop();
-                }
-                prefix
-            });
+        let client = Client::from_conf(config_builder.build());

+        let prefix_in_bucket = aws_config.prefix_in_bucket.as_deref().map(|prefix| {
+            let mut prefix = prefix;
+            while prefix.starts_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
+                prefix = &prefix[1..]
+            }
+
+            let mut prefix = prefix.to_string();
+            while prefix.ends_with(REMOTE_STORAGE_PREFIX_SEPARATOR) {
+                prefix.pop();
+            }
+            prefix
+        });
        Ok(Self {
            client,
-            bucket_name: remote_storage_config.bucket_name.clone(),
-            max_keys_per_list_response: remote_storage_config.max_keys_per_list_response,
+            bucket_name: aws_config.bucket_name.clone(),
+            max_keys_per_list_response: aws_config.max_keys_per_list_response,
            prefix_in_bucket,
-            concurrency_limiter: ConcurrencyLimiter::new(
-                remote_storage_config.concurrency_limit.get(),
-            ),
-            upload_storage_class: remote_storage_config.upload_storage_class.clone(),
+            concurrency_limiter: ConcurrencyLimiter::new(aws_config.concurrency_limit.get()),
+            upload_storage_class: aws_config.upload_storage_class.clone(),
            timeout,
        })
    }
--- a/libs/utils/src/poison.rs
+++ b/libs/utils/src/poison.rs
@@ -3,7 +3,7 @@
 //!  # Example
 //!
 //!  ```
-//!  # tokio::runtime::Builder::new_current_thread().enable_all().build().unwrap().block_on(async {
+//!  # tokio_test::block_on(async {
 //!  use utils::poison::Poison;
 //!  use std::time::Duration;
 //!
--- a/libs/walproposer/src/api_bindings.rs
+++ b/libs/walproposer/src/api_bindings.rs
@@ -50,14 +50,6 @@ extern "C" fn get_flush_rec_ptr(wp: *mut WalProposer) -> XLogRecPtr {
    }
 }

-extern "C" fn update_donor(wp: *mut WalProposer, donor: *mut Safekeeper, donor_lsn: XLogRecPtr) {
-    unsafe {
-        let callback_data = (*(*wp).config).callback_data;
-        let api = callback_data as *mut Box<dyn ApiImpl>;
-        (*api).update_donor(&mut (*donor), donor_lsn)
-    }
-}
-
 extern "C" fn get_current_timestamp(wp: *mut WalProposer) -> TimestampTz {
    unsafe {
        let callback_data = (*(*wp).config).callback_data;
@@ -399,7 +391,6 @@ pub(crate) fn create_api() -> walproposer_api {
        get_shmem_state: Some(get_shmem_state),
        start_streaming: Some(start_streaming),
        get_flush_rec_ptr: Some(get_flush_rec_ptr),
-        update_donor: Some(update_donor),
        get_current_timestamp: Some(get_current_timestamp),
        conn_error_message: Some(conn_error_message),
        conn_status: Some(conn_status),
@@ -430,32 +421,6 @@ pub(crate) fn create_api() -> walproposer_api {
    }
 }

-pub fn empty_shmem() -> crate::bindings::WalproposerShmemState {
-    let empty_feedback = crate::bindings::PageserverFeedback {
-        present: false,
-        currentClusterSize: 0,
-        last_received_lsn: 0,
-        disk_consistent_lsn: 0,
-        remote_consistent_lsn: 0,
-        replytime: 0,
-        shard_number: 0,
-    };
-
-    crate::bindings::WalproposerShmemState {
-        propEpochStartLsn: crate::bindings::pg_atomic_uint64 { value: 0 },
-        donor_name: [0; 64],
-        donor_conninfo: [0; 1024],
-        donor_lsn: 0,
-        mutex: 0,
-        mineLastElectedTerm: crate::bindings::pg_atomic_uint64 { value: 0 },
-        backpressureThrottlingTime: crate::bindings::pg_atomic_uint64 { value: 0 },
-        currentClusterSize: crate::bindings::pg_atomic_uint64 { value: 0 },
-        shard_ps_feedback: [empty_feedback; 128],
-        num_shards: 0,
-        min_ps_feedback: empty_feedback,
-    }
-}
-
 impl std::fmt::Display for Level {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        write!(f, "{:?}", self)
--- a/libs/walproposer/src/walproposer.rs
+++ b/libs/walproposer/src/walproposer.rs
@@ -1,5 +1,8 @@
 use std::ffi::CString;

+use postgres_ffi::WAL_SEGMENT_SIZE;
+use utils::{id::TenantTimelineId, lsn::Lsn};
+
 use crate::{
    api_bindings::{create_api, take_vec_u8, Level},
    bindings::{
@@ -7,8 +10,6 @@ use crate::{
        WalProposerCreate, WalProposerFree, WalProposerPoll, WalProposerStart,
    },
 };
-use postgres_ffi::WAL_SEGMENT_SIZE;
-use utils::{id::TenantTimelineId, lsn::Lsn};

 /// Rust high-level wrapper for C walproposer API. Many methods are not required
 /// for simple cases, hence todo!() in default implementations.
@@ -27,10 +28,6 @@ pub trait ApiImpl {
        todo!()
    }

-    fn update_donor(&self, _donor: &mut Safekeeper, _donor_lsn: u64) {
-        todo!()
-    }
-
    fn get_current_timestamp(&self) -> i64 {
        todo!()
    }
@@ -277,7 +274,6 @@ mod tests {
        sync::{atomic::AtomicUsize, mpsc::sync_channel},
    };

-    use std::cell::UnsafeCell;
    use utils::id::TenantTimelineId;

    use crate::{api_bindings::Level, bindings::NeonWALReadResult, walproposer::Wrapper};
@@ -301,8 +297,6 @@ mod tests {
        replies_ptr: AtomicUsize,
        // channel to send LSN to the main thread
        sync_channel: std::sync::mpsc::SyncSender<u64>,
-        // Shmem state, used for storing donor info
-        shmem: UnsafeCell<crate::bindings::WalproposerShmemState>,
    }

    impl MockImpl {
@@ -333,22 +327,11 @@ mod tests {
    }

    impl ApiImpl for MockImpl {
-        fn get_shmem_state(&self) -> *mut crate::bindings::WalproposerShmemState {
-            self.shmem.get()
-        }
-
        fn get_current_timestamp(&self) -> i64 {
            println!("get_current_timestamp");
            0
        }

-        fn update_donor(&self, donor: &mut crate::bindings::Safekeeper, donor_lsn: u64) {
-            let mut shmem = unsafe { *self.get_shmem_state() };
-            shmem.propEpochStartLsn.value = donor_lsn;
-            shmem.donor_conninfo = donor.conninfo;
-            shmem.donor_lsn = donor_lsn;
-        }
-
        fn conn_status(
            &self,
            _: &mut crate::bindings::Safekeeper,
@@ -524,7 +507,6 @@ mod tests {
            ],
            replies_ptr: AtomicUsize::new(0),
            sync_channel: sender,
-            shmem: UnsafeCell::new(crate::api_bindings::empty_shmem()),
        });
        let config = crate::walproposer::Config {
            ttid,
--- a/pageserver/benches/bench_layer_map.rs
+++ b/pageserver/benches/bench_layer_map.rs
@@ -1,7 +1,7 @@
 use pageserver::keyspace::{KeyPartitioning, KeySpace};
 use pageserver::repository::Key;
 use pageserver::tenant::layer_map::LayerMap;
-use pageserver::tenant::storage_layer::LayerName;
+use pageserver::tenant::storage_layer::LayerFileName;
 use pageserver::tenant::storage_layer::PersistentLayerDesc;
 use pageserver_api::shard::TenantShardId;
 use rand::prelude::{SeedableRng, SliceRandom, StdRng};
@@ -28,7 +28,7 @@ fn build_layer_map(filename_dump: PathBuf) -> LayerMap {
    let mut updates = layer_map.batch_update();
    for fname in filenames {
        let fname = fname.unwrap();
-        let fname = LayerName::from_str(&fname).unwrap();
+        let fname = LayerFileName::from_str(&fname).unwrap();
        let layer = PersistentLayerDesc::from(fname);

        let lsn_range = layer.get_lsn_range();
--- a/pageserver/client/src/mgmt_api.rs
+++ b/pageserver/client/src/mgmt_api.rs
@@ -284,34 +284,6 @@ impl Client {
        Ok((status, progress))
    }

-    pub async fn tenant_secondary_status(
-        &self,
-        tenant_shard_id: TenantShardId,
-    ) -> Result<SecondaryProgress> {
-        let path = reqwest::Url::parse(&format!(
-            "{}/v1/tenant/{}/secondary/status",
-            self.mgmt_api_endpoint, tenant_shard_id
-        ))
-        .expect("Cannot build URL");
-
-        self.request(Method::GET, path, ())
-            .await?
-            .json()
-            .await
-            .map_err(Error::ReceiveBody)
-    }
-
-    pub async fn tenant_heatmap_upload(&self, tenant_id: TenantShardId) -> Result<()> {
-        let path = reqwest::Url::parse(&format!(
-            "{}/v1/tenant/{}/heatmap_upload",
-            self.mgmt_api_endpoint, tenant_id
-        ))
-        .expect("Cannot build URL");
-
-        self.request(Method::POST, path, ()).await?;
-        Ok(())
-    }
-
    pub async fn location_config(
        &self,
        tenant_shard_id: TenantShardId,
@@ -319,7 +291,10 @@ impl Client {
        flush_ms: Option<std::time::Duration>,
        lazy: bool,
    ) -> Result<()> {
-        let req_body = TenantLocationConfigRequest { config };
+        let req_body = TenantLocationConfigRequest {
+            tenant_id: None,
+            config,
+        };

        let mut path = reqwest::Url::parse(&format!(
            "{}/v1/tenant/{}/location_config",
--- a/pageserver/compaction/src/compact_tiered.rs
+++ b/pageserver/compaction/src/compact_tiered.rs
@@ -24,9 +24,7 @@ use tracing::{debug, info};
 use std::collections::{HashSet, VecDeque};
 use std::ops::Range;

-use crate::helpers::{
-    accum_key_values, keyspace_total_size, merge_delta_keys_buffered, overlaps_with,
-};
+use crate::helpers::{accum_key_values, keyspace_total_size, merge_delta_keys, overlaps_with};
 use crate::interface::*;
 use utils::lsn::Lsn;

@@ -106,13 +104,7 @@ pub async fn compact_tiered<E: CompactionJobExecutor>(
            ctx,
        )
        .await?;
-        if current_level_target_height == u64::MAX {
-            // our target height includes all possible lsns
-            info!(
-                level = current_level_no,
-                depth = depth,
-                "compaction loop reached max current_level_target_height"
-            );
+        if target_file_size == u64::MAX {
            break;
        }
        current_level_no += 1;
@@ -543,10 +535,7 @@ where
            }
        }
        // Open stream
-        let key_value_stream =
-            std::pin::pin!(merge_delta_keys_buffered::<E>(deltas.as_slice(), ctx)
-                .await?
-                .map(Result::<_, anyhow::Error>::Ok));
+        let key_value_stream = std::pin::pin!(merge_delta_keys::<E>(deltas.as_slice(), ctx));
        let mut new_jobs = Vec::new();

        // Slide a window through the keyspace
--- a/pageserver/compaction/src/helpers.rs
+++ b/pageserver/compaction/src/helpers.rs
@@ -9,12 +9,10 @@ use pageserver_api::shard::ShardIdentity;
 use pin_project_lite::pin_project;
 use std::collections::BinaryHeap;
 use std::collections::VecDeque;
-use std::fmt::Display;
 use std::future::Future;
 use std::ops::{DerefMut, Range};
 use std::pin::Pin;
 use std::task::{ready, Poll};
-use utils::lsn::Lsn;

 pub fn keyspace_total_size<K>(
    keyspace: &CompactionKeySpace<K>,
@@ -110,40 +108,17 @@ pub fn merge_delta_keys<'a, E: CompactionJobExecutor>(
    }
 }

-pub async fn merge_delta_keys_buffered<'a, E: CompactionJobExecutor + 'a>(
-    layers: &'a [E::DeltaLayer],
-    ctx: &'a E::RequestContext,
-) -> anyhow::Result<impl Stream<Item = <E::DeltaLayer as CompactionDeltaLayer<E>>::DeltaEntry<'a>>>
-{
-    let mut keys = Vec::new();
-    for l in layers {
-        // Boxing and casting to LoadFuture is required to obtain the right Sync bound.
-        // If we do l.load_keys(ctx).await? directly, there is a compilation error.
-        let load_future: LoadFuture<'a, _> = Box::pin(l.load_keys(ctx));
-        keys.extend(load_future.await?.into_iter());
-    }
-    keys.sort_by_key(|k| (k.key(), k.lsn()));
-    let stream = futures::stream::iter(keys.into_iter());
-    Ok(stream)
-}
-
 enum LazyLoadLayer<'a, E: CompactionJobExecutor> {
    Loaded(VecDeque<<E::DeltaLayer as CompactionDeltaLayer<E>>::DeltaEntry<'a>>),
    Unloaded(&'a E::DeltaLayer),
 }
 impl<'a, E: CompactionJobExecutor> LazyLoadLayer<'a, E> {
-    fn min_key(&self) -> E::Key {
+    fn key(&self) -> E::Key {
        match self {
            Self::Loaded(entries) => entries.front().unwrap().key(),
            Self::Unloaded(dl) => dl.key_range().start,
        }
    }
-    fn min_lsn(&self) -> Lsn {
-        match self {
-            Self::Loaded(entries) => entries.front().unwrap().lsn(),
-            Self::Unloaded(dl) => dl.lsn_range().start,
-        }
-    }
 }
 impl<'a, E: CompactionJobExecutor> PartialOrd for LazyLoadLayer<'a, E> {
    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
@@ -153,12 +128,12 @@ impl<'a, E: CompactionJobExecutor> PartialOrd for LazyLoadLayer<'a, E> {
 impl<'a, E: CompactionJobExecutor> Ord for LazyLoadLayer<'a, E> {
    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
        // reverse order so that we get a min-heap
-        (other.min_key(), other.min_lsn()).cmp(&(self.min_key(), self.min_lsn()))
+        other.key().cmp(&self.key())
    }
 }
 impl<'a, E: CompactionJobExecutor> PartialEq for LazyLoadLayer<'a, E> {
    fn eq(&self, other: &Self) -> bool {
-        self.cmp(other) == std::cmp::Ordering::Equal
+        self.key().eq(&other.key())
    }
 }
 impl<'a, E: CompactionJobExecutor> Eq for LazyLoadLayer<'a, E> {}
@@ -239,7 +214,7 @@ pub struct KeySize<K> {

 pub fn accum_key_values<'a, I, K, D, E>(input: I) -> impl Stream<Item = Result<KeySize<K>, E>>
 where
-    K: Eq + PartialOrd + Display + Copy,
+    K: Eq,
    I: Stream<Item = Result<D, E>>,
    D: CompactionDeltaEntry<'a, K>,
 {
@@ -254,15 +229,12 @@ where
                num_values: 1,
                size: first.size(),
            };
-            let mut last_key = accum.key;
            while let Some(this) = input.next().await {
                let this = this?;
                if this.key() == accum.key {
                    accum.size += this.size();
                    accum.num_values += 1;
                } else {
-                    assert!(last_key <= accum.key, "last_key={last_key} <= accum.key={}", accum.key);
-                    last_key = accum.key;
                    yield accum;
                    accum = KeySize {
                        key: this.key(),
@@ -271,7 +243,6 @@ where
                    };
                }
            }
-            assert!(last_key <= accum.key, "last_key={last_key} <= accum.key={}", accum.key);
            yield accum;
        }
    }
--- a/pageserver/compaction/tests/tests.rs
+++ b/pageserver/compaction/tests/tests.rs
@@ -1,20 +1,5 @@
-use once_cell::sync::OnceCell;
 use pageserver_compaction::interface::CompactionLayer;
 use pageserver_compaction::simulator::MockTimeline;
-use utils::logging;
-
-static LOG_HANDLE: OnceCell<()> = OnceCell::new();
-
-pub(crate) fn setup_logging() {
-    LOG_HANDLE.get_or_init(|| {
-        logging::init(
-            logging::LogFormat::Test,
-            logging::TracingErrorLayerEnablement::EnableWithRustLogFilter,
-            logging::Output::Stdout,
-        )
-        .expect("Failed to init test logging")
-    });
-}

 /// Test the extreme case that there are so many updates for a single key that
 /// even if we produce an extremely narrow delta layer, spanning just that one
@@ -26,14 +11,13 @@ pub(crate) fn setup_logging() {
 #[ignore]
 #[tokio::test]
 async fn test_many_updates_for_single_key() {
-    setup_logging();
    let mut executor = MockTimeline::new();
-    executor.target_file_size = 1_000_000; // 1 MB
+    executor.target_file_size = 10_000_000; // 10 MB

-    // Ingest 10 MB of updates to a single key.
+    // Ingest 100 MB of updates to a single key.
    for _ in 1..1000 {
        executor.ingest_uniform(100, 10, &(0..100_000)).unwrap();
-        executor.ingest_uniform(1000, 10, &(0..1)).unwrap();
+        executor.ingest_uniform(10_000, 10, &(0..1)).unwrap();
        executor.compact().await.unwrap();
    }

@@ -49,26 +33,3 @@ async fn test_many_updates_for_single_key() {
        }
    }
 }
-
-#[tokio::test]
-async fn test_simple_updates() {
-    setup_logging();
-    let mut executor = MockTimeline::new();
-    executor.target_file_size = 500_000; // 500 KB
-
-    // Ingest some traffic.
-    for _ in 1..400 {
-        executor.ingest_uniform(100, 500, &(0..100_000)).unwrap();
-    }
-
-    for l in executor.live_layers.iter() {
-        println!("layer {}: {}", l.short_id(), l.file_size());
-    }
-
-    println!("Running compaction...");
-    executor.compact().await.unwrap();
-
-    for l in executor.live_layers.iter() {
-        println!("layer {}: {}", l.short_id(), l.file_size());
-    }
-}
--- a/pageserver/ctl/src/draw_timeline_dir.rs
+++ b/pageserver/ctl/src/draw_timeline_dir.rs
@@ -28,8 +28,6 @@
 //! # From an `index_part.json` in S3
 //! (jq -r '.layer_metadata | keys[]' | cargo  run -p pagectl draw-timeline ) < index_part.json-00000016 > out.svg
 //!
-//! # enrich with lines for gc_cutoff and a child branch point
-//! cat <(jq -r '.historic_layers[] | .layer_file_name' < layers.json) <(echo -e 'gc_cutoff:0000001CE3FE32C9\nbranch:0000001DE3FE32C9') | cargo run --bin pagectl draw-timeline >| out.svg
 //! ```
 //!
 //! ## Viewing
@@ -50,7 +48,7 @@
 //! ```
 //!

-use anyhow::{Context, Result};
+use anyhow::Result;
 use pageserver::repository::Key;
 use pageserver::METADATA_FILE_NAME;
 use std::cmp::Ordering;
@@ -92,33 +90,6 @@ fn parse_filename(name: &str) -> (Range<Key>, Range<Lsn>) {
    (keys, lsns)
 }

-#[derive(Clone, Copy)]
-enum LineKind {
-    GcCutoff,
-    Branch,
-}
-
-impl From<LineKind> for Fill {
-    fn from(value: LineKind) -> Self {
-        match value {
-            LineKind::GcCutoff => Fill::Color(rgb(255, 0, 0)),
-            LineKind::Branch => Fill::Color(rgb(0, 255, 0)),
-        }
-    }
-}
-
-impl FromStr for LineKind {
-    type Err = anyhow::Error;
-
-    fn from_str(s: &str) -> std::prelude::v1::Result<Self, Self::Err> {
-        Ok(match s {
-            "gc_cutoff" => LineKind::GcCutoff,
-            "branch" => LineKind::Branch,
-            _ => anyhow::bail!("unsupported linekind: {s}"),
-        })
-    }
-}
-
 pub fn main() -> Result<()> {
    // Parse layer filenames from stdin
    struct Layer {
@@ -128,29 +99,8 @@ pub fn main() -> Result<()> {
    }
    let mut files: Vec<Layer> = vec![];
    let stdin = io::stdin();
-
-    let mut lines: Vec<(Lsn, LineKind)> = vec![];
-
-    for (lineno, line) in stdin.lock().lines().enumerate() {
-        let lineno = lineno + 1;
-
+    for line in stdin.lock().lines() {
        let line = line.unwrap();
-        if let Some((kind, lsn)) = line.split_once(':') {
-            let (kind, lsn) = LineKind::from_str(kind)
-                .context("parse kind")
-                .and_then(|kind| {
-                    if lsn.contains('/') {
-                        Lsn::from_str(lsn)
-                    } else {
-                        Lsn::from_hex(lsn)
-                    }
-                    .map(|lsn| (kind, lsn))
-                    .context("parse lsn")
-                })
-                .with_context(|| format!("parse {line:?} on {lineno}"))?;
-            lines.push((lsn, kind));
-            continue;
-        }
        let line = PathBuf::from_str(&line).unwrap();
        let filename = line.file_name().unwrap();
        let filename = filename.to_str().unwrap();
@@ -167,9 +117,8 @@ pub fn main() -> Result<()> {
    }

    // Collect all coordinates
-    let mut keys: Vec<Key> = Vec::with_capacity(files.len());
-    let mut lsns: Vec<Lsn> = Vec::with_capacity(files.len() + lines.len());
-
+    let mut keys: Vec<Key> = vec![];
+    let mut lsns: Vec<Lsn> = vec![];
    for Layer {
        key_range: keyr,
        lsn_range: lsnr,
@@ -182,8 +131,6 @@ pub fn main() -> Result<()> {
        lsns.push(lsnr.end);
    }

-    lsns.extend(lines.iter().map(|(lsn, _)| *lsn));
-
    // Analyze
    let key_map = build_coordinate_compression_map(keys);
    let lsn_map = build_coordinate_compression_map(lsns);
@@ -197,13 +144,10 @@ pub fn main() -> Result<()> {
    println!(
        "{}",
        BeginSvg {
-            w: (key_map.len() + 10) as f32,
+            w: key_map.len() as f32,
            h: stretch * lsn_map.len() as f32
        }
    );
-
-    let xmargin = 0.05; // Height-dependent margin to disambiguate overlapping deltas
-
    for Layer {
        filename,
        key_range: keyr,
@@ -225,6 +169,7 @@ pub fn main() -> Result<()> {
        let mut lsn_diff = (lsn_end - lsn_start) as f32;
        let mut fill = Fill::None;
        let mut ymargin = 0.05 * lsn_diff; // Height-dependent margin to disambiguate overlapping deltas
+        let xmargin = 0.05; // Height-dependent margin to disambiguate overlapping deltas
        let mut lsn_offset = 0.0;

        // Fill in and thicken rectangle if it's an
@@ -244,7 +189,7 @@ pub fn main() -> Result<()> {
        println!(
            "    {}",
            rectangle(
-                5.0 + key_start as f32 + stretch * xmargin,
+                key_start as f32 + stretch * xmargin,
                stretch * (lsn_max as f32 - (lsn_end as f32 - ymargin - lsn_offset)),
                key_diff as f32 - stretch * 2.0 * xmargin,
                stretch * (lsn_diff - 2.0 * ymargin)
@@ -255,26 +200,6 @@ pub fn main() -> Result<()> {
            .comment(filename)
        );
    }
-
-    for (lsn, kind) in lines {
-        let lsn_start = *lsn_map.get(&lsn).unwrap();
-        let lsn_end = lsn_start;
-        let stretch = 2.0;
-        let lsn_diff = 0.3;
-        let lsn_offset = -lsn_diff / 2.0;
-        let ymargin = 0.05;
-        println!(
-            "{}",
-            rectangle(
-                0.0f32 + stretch * xmargin,
-                stretch * (lsn_map.len() as f32 - (lsn_end as f32 - ymargin - lsn_offset)),
-                (key_map.len() + 10) as f32,
-                stretch * (lsn_diff - 2.0 * ymargin)
-            )
-            .fill(kind)
-        );
-    }
-
    println!("{}", EndSvg);

    eprintln!("num_images: {}", num_images);
--- a/pageserver/ctl/src/index_part.rs
+++ b/pageserver/ctl/src/index_part.rs
@@ -3,7 +3,7 @@ use std::collections::HashMap;
 use anyhow::Context;
 use camino::Utf8PathBuf;
 use pageserver::tenant::remote_timeline_client::index::IndexLayerMetadata;
-use pageserver::tenant::storage_layer::LayerName;
+use pageserver::tenant::storage_layer::LayerFileName;
 use pageserver::tenant::{metadata::TimelineMetadata, IndexPart};
 use utils::lsn::Lsn;

@@ -19,7 +19,7 @@ pub(crate) async fn main(cmd: &IndexPartCmd) -> anyhow::Result<()> {
            let des: IndexPart = IndexPart::from_s3_bytes(&bytes).context("deserialize")?;
            #[derive(serde::Serialize)]
            struct Output<'a> {
-                layer_metadata: &'a HashMap<LayerName, IndexLayerMetadata>,
+                layer_metadata: &'a HashMap<LayerFileName, IndexLayerMetadata>,
                disk_consistent_lsn: Lsn,
                timeline_metadata: &'a TimelineMetadata,
            }
--- a/pageserver/src/aux_file.rs
+++ b/pageserver/src/aux_file.rs
@@ -1,4 +1,3 @@
-use bytes::{Buf, BufMut, Bytes};
 use pageserver_api::key::{Key, AUX_KEY_PREFIX, METADATA_KEY_SIZE};
 use tracing::warn;

@@ -62,84 +61,6 @@ pub fn encode_aux_file_key(path: &str) -> Key {
    }
 }

-const AUX_FILE_ENCODING_VERSION: u8 = 0x01;
-
-pub fn decode_file_value(val: &[u8]) -> anyhow::Result<Vec<(&str, &[u8])>> {
-    let mut ptr = val;
-    if ptr.is_empty() {
-        // empty value = no files
-        return Ok(Vec::new());
-    }
-    assert_eq!(
-        ptr.get_u8(),
-        AUX_FILE_ENCODING_VERSION,
-        "unsupported aux file value"
-    );
-    let mut files = vec![];
-    while ptr.has_remaining() {
-        let key_len = ptr.get_u32() as usize;
-        let key = &ptr[..key_len];
-        ptr.advance(key_len);
-        let val_len = ptr.get_u32() as usize;
-        let content = &ptr[..val_len];
-        ptr.advance(val_len);
-
-        let path = std::str::from_utf8(key)?;
-        files.push((path, content));
-    }
-    Ok(files)
-}
-
-/// Decode an aux file key-value pair into a list of files. The returned `Bytes` contains reference
-/// to the original value slice. Be cautious about memory consumption.
-pub fn decode_file_value_bytes(val: &Bytes) -> anyhow::Result<Vec<(String, Bytes)>> {
-    let mut ptr = val.clone();
-    if ptr.is_empty() {
-        // empty value = no files
-        return Ok(Vec::new());
-    }
-    assert_eq!(
-        ptr.get_u8(),
-        AUX_FILE_ENCODING_VERSION,
-        "unsupported aux file value"
-    );
-    let mut files = vec![];
-    while ptr.has_remaining() {
-        let key_len = ptr.get_u32() as usize;
-        let key = ptr.slice(..key_len);
-        ptr.advance(key_len);
-        let val_len = ptr.get_u32() as usize;
-        let content = ptr.slice(..val_len);
-        ptr.advance(val_len);
-
-        let path = std::str::from_utf8(&key)?.to_string();
-        files.push((path, content));
-    }
-    Ok(files)
-}
-
-pub fn encode_file_value(files: &[(&str, &[u8])]) -> anyhow::Result<Vec<u8>> {
-    if files.is_empty() {
-        // no files = empty value
-        return Ok(Vec::new());
-    }
-    let mut encoded = vec![];
-    encoded.put_u8(AUX_FILE_ENCODING_VERSION);
-    for (path, content) in files {
-        if path.len() > u32::MAX as usize {
-            anyhow::bail!("{} exceeds path size limit", path);
-        }
-        encoded.put_u32(path.len() as u32);
-        encoded.put_slice(path.as_bytes());
-        if content.len() > u32::MAX as usize {
-            anyhow::bail!("{} exceeds content size limit", path);
-        }
-        encoded.put_u32(content.len() as u32);
-        encoded.put_slice(content);
-    }
-    Ok(encoded)
-}
-
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -188,21 +109,4 @@ mod tests {
            encode_aux_file_key("other_file_not_supported").to_string()
        );
    }
-
-    #[test]
-    fn test_value_encoding() {
-        let files = vec![
-            ("pg_logical/1.file", "1111".as_bytes()),
-            ("pg_logical/2.file", "2222".as_bytes()),
-        ];
-        assert_eq!(
-            files,
-            decode_file_value(&encode_file_value(&files).unwrap()).unwrap()
-        );
-        let files = vec![];
-        assert_eq!(
-            files,
-            decode_file_value(&encode_file_value(&files).unwrap()).unwrap()
-        );
-    }
 }
--- a/pageserver/src/basebackup.rs
+++ b/pageserver/src/basebackup.rs
@@ -601,7 +601,7 @@ where
        // add zenith.signal file
        let mut zenith_signal = String::new();
        if self.prev_record_lsn == Lsn(0) {
-            if self.timeline.is_ancestor_lsn(self.lsn) {
+            if self.lsn == self.timeline.get_ancestor_lsn() {
                write!(zenith_signal, "PREV LSN: none")
                    .map_err(|e| BasebackupError::Server(e.into()))?;
            } else {
--- a/pageserver/src/bin/pageserver.rs
+++ b/pageserver/src/bin/pageserver.rs
@@ -3,7 +3,6 @@
 //! Main entry point for the Page Server executable.

 use std::env::{var, VarError};
-use std::io::Read;
 use std::sync::Arc;
 use std::time::Duration;
 use std::{env, ops::ControlFlow, str::FromStr};
@@ -152,34 +151,37 @@ fn initialize_config(
    workdir: &Utf8Path,
 ) -> anyhow::Result<ControlFlow<(), &'static PageServerConf>> {
    let init = arg_matches.get_flag("init");
+    let update_config = init || arg_matches.get_flag("update-config");

-    let file_contents: Option<toml_edit::Document> = match std::fs::File::open(cfg_file_path) {
-        Ok(mut f) => {
-            if init {
-                anyhow::bail!("config file already exists: {cfg_file_path}");
-            }
-            let md = f.metadata().context("stat config file")?;
-            if md.is_file() {
-                let mut s = String::new();
-                f.read_to_string(&mut s).context("read config file")?;
-                Some(s.parse().context("parse config file toml")?)
-            } else {
-                anyhow::bail!("directory entry exists but is not a file: {cfg_file_path}");
-            }
-        }
-        Err(e) if e.kind() == std::io::ErrorKind::NotFound => None,
-        Err(e) => {
-            anyhow::bail!("open pageserver config: {e}: {cfg_file_path}");
+    let (mut toml, config_file_exists) = if cfg_file_path.is_file() {
+        if init {
+            anyhow::bail!(
+                "Config file '{cfg_file_path}' already exists, cannot init it, use --update-config to update it",
+            );
        }
+        // Supplement the CLI arguments with the config file
+        let cfg_file_contents = std::fs::read_to_string(cfg_file_path)
+            .with_context(|| format!("Failed to read pageserver config at '{cfg_file_path}'"))?;
+        (
+            cfg_file_contents
+                .parse::<toml_edit::Document>()
+                .with_context(|| {
+                    format!("Failed to parse '{cfg_file_path}' as pageserver config")
+                })?,
+            true,
+        )
+    } else if cfg_file_path.exists() {
+        anyhow::bail!("Config file '{cfg_file_path}' exists but is not a regular file");
+    } else {
+        // We're initializing the tenant, so there's no config file yet
+        (
+            DEFAULT_CONFIG_FILE
+                .parse::<toml_edit::Document>()
+                .context("could not parse built-in config file")?,
+            false,
+        )
    };

-    let mut effective_config = file_contents.unwrap_or_else(|| {
-        DEFAULT_CONFIG_FILE
-            .parse()
-            .expect("unit tests ensure this works")
-    });
-
-    // Patch with overrides from the command line
    if let Some(values) = arg_matches.get_many::<String>("config-override") {
        for option_line in values {
            let doc = toml_edit::Document::from_str(option_line).with_context(|| {
@@ -187,21 +189,22 @@ fn initialize_config(
            })?;

            for (key, item) in doc.iter() {
-                effective_config.insert(key, item.clone());
+                if config_file_exists && update_config && key == "id" && toml.contains_key(key) {
+                    anyhow::bail!("Pageserver config file exists at '{cfg_file_path}' and has node id already, it cannot be overridden");
+                }
+                toml.insert(key, item.clone());
            }
        }
    }

-    debug!("Resulting toml: {effective_config}");
-
-    // Construct the runtime representation
-    let conf = PageServerConf::parse_and_validate(&effective_config, workdir)
+    debug!("Resulting toml: {toml}");
+    let conf = PageServerConf::parse_and_validate(&toml, workdir)
        .context("Failed to parse pageserver configuration")?;

-    if init {
+    if update_config {
        info!("Writing pageserver config to '{cfg_file_path}'");

-        std::fs::write(cfg_file_path, effective_config.to_string())
+        std::fs::write(cfg_file_path, toml.to_string())
            .with_context(|| format!("Failed to write pageserver config to '{cfg_file_path}'"))?;
        info!("Config successfully written to '{cfg_file_path}'")
    }
@@ -755,13 +758,18 @@ fn cli() -> Command {
        // See `settings.md` for more details on the extra configuration patameters pageserver can process
        .arg(
            Arg::new("config-override")
-                .long("config-override")
                .short('c')
                .num_args(1)
                .action(ArgAction::Append)
                .help("Additional configuration overrides of the ones from the toml config file (or new ones to add there). \
                Any option has to be a valid toml document, example: `-c=\"foo='hey'\"` `-c=\"foo={value=1}\"`"),
        )
+        .arg(
+            Arg::new("update-config")
+                .long("update-config")
+                .action(ArgAction::SetTrue)
+                .help("Update the config file when started"),
+        )
        .arg(
            Arg::new("enabled-features")
                .long("enabled-features")
--- a/pageserver/src/config.rs
+++ b/pageserver/src/config.rs
@@ -9,7 +9,7 @@ use pageserver_api::shard::TenantShardId;
 use remote_storage::{RemotePath, RemoteStorageConfig};
 use serde;
 use serde::de::IntoDeserializer;
-use std::env;
+use std::{collections::HashMap, env};
 use storage_broker::Uri;
 use utils::crashsafe::path_with_suffix_extension;
 use utils::id::ConnectionId;
@@ -51,7 +51,7 @@ pub mod defaults {
    use crate::tenant::config::defaults::*;
    use const_format::formatcp;

-    pub use pageserver_api::config::{
+    pub use pageserver_api::{
        DEFAULT_HTTP_LISTEN_ADDR, DEFAULT_HTTP_LISTEN_PORT, DEFAULT_PG_LISTEN_ADDR,
        DEFAULT_PG_LISTEN_PORT,
    };
@@ -335,6 +335,26 @@ impl<T: Clone> BuilderValue<T> {
    }
 }

+// Certain metadata (e.g. externally-addressable name, AZ) is delivered
+// as a separate structure.  This information is not neeed by the pageserver
+// itself, it is only used for registering the pageserver with the control
+// plane and/or storage controller.
+//
+#[derive(serde::Deserialize)]
+pub(crate) struct NodeMetadata {
+    #[serde(rename = "host")]
+    pub(crate) postgres_host: String,
+    #[serde(rename = "port")]
+    pub(crate) postgres_port: u16,
+    pub(crate) http_host: String,
+    pub(crate) http_port: u16,
+
+    // Deployment tools may write fields to the metadata file beyond what we
+    // use in this type: this type intentionally only names fields that require.
+    #[serde(flatten)]
+    pub(crate) other: HashMap<String, serde_json::Value>,
+}
+
 // needed to simplify config construction
 #[derive(Default)]
 struct PageServerConfigBuilder {
--- a/pageserver/src/control_plane_client.rs
+++ b/pageserver/src/control_plane_client.rs
@@ -14,8 +14,10 @@ use tokio_util::sync::CancellationToken;
 use url::Url;
 use utils::{backoff, failpoint_support, generation::Generation, id::NodeId};

-use crate::{config::PageServerConf, virtual_file::on_fatal_io_error};
-use pageserver_api::config::NodeMetadata;
+use crate::{
+    config::{NodeMetadata, PageServerConf},
+    virtual_file::on_fatal_io_error,
+};

 /// The Pageserver's client for using the control plane API: this is a small subset
 /// of the overall control plane API, for dealing with generations (see docs/rfcs/025-generation-numbers.md)
@@ -63,7 +65,7 @@ impl ControlPlaneClient {
        let mut client = reqwest::ClientBuilder::new();

        if let Some(jwt) = &conf.control_plane_api_token {
-            let mut headers = reqwest::header::HeaderMap::new();
+            let mut headers = hyper::HeaderMap::new();
            headers.insert(
                "Authorization",
                format!("Bearer {}", jwt.get_contents()).parse().unwrap(),
--- a/pageserver/src/deletion_queue.rs
+++ b/pageserver/src/deletion_queue.rs
@@ -38,7 +38,7 @@ use deleter::DeleterMessage;
 use list_writer::ListWriterQueueMessage;
 use validator::ValidatorQueueMessage;

-use crate::{config::PageServerConf, tenant::storage_layer::LayerName};
+use crate::{config::PageServerConf, tenant::storage_layer::LayerFileName};

 // TODO: configurable for how long to wait before executing deletions

@@ -479,7 +479,7 @@ impl DeletionQueueClient {
        tenant_shard_id: TenantShardId,
        timeline_id: TimelineId,
        current_generation: Generation,
-        layers: Vec<(LayerName, LayerFileMetadata)>,
+        layers: Vec<(LayerFileName, LayerFileMetadata)>,
    ) -> Result<(), DeletionQueueError> {
        if current_generation.is_none() {
            debug!("Enqueuing deletions in legacy mode, skipping queue");
@@ -511,7 +511,7 @@ impl DeletionQueueClient {
        tenant_shard_id: TenantShardId,
        timeline_id: TimelineId,
        current_generation: Generation,
-        layers: Vec<(LayerName, LayerFileMetadata)>,
+        layers: Vec<(LayerFileName, LayerFileMetadata)>,
    ) -> Result<(), DeletionQueueError> {
        metrics::DELETION_QUEUE
            .keys_submitted
@@ -734,20 +734,20 @@ mod test {
    use crate::{
        control_plane_client::RetryForeverError,
        repository::Key,
-        tenant::{harness::TenantHarness, storage_layer::DeltaLayerName},
+        tenant::{harness::TenantHarness, storage_layer::DeltaFileName},
    };

    use super::*;
    pub const TIMELINE_ID: TimelineId =
        TimelineId::from_array(hex!("11223344556677881122334455667788"));

-    pub const EXAMPLE_LAYER_NAME: LayerName = LayerName::Delta(DeltaLayerName {
+    pub const EXAMPLE_LAYER_NAME: LayerFileName = LayerFileName::Delta(DeltaFileName {
        key_range: Key::from_i128(0x0)..Key::from_i128(0xFFFFFFFFFFFFFFFF),
        lsn_range: Lsn(0x00000000016B59D8)..Lsn(0x00000000016B5A51),
    });

    // When you need a second layer in a test.
-    pub const EXAMPLE_LAYER_NAME_ALT: LayerName = LayerName::Delta(DeltaLayerName {
+    pub const EXAMPLE_LAYER_NAME_ALT: LayerFileName = LayerFileName::Delta(DeltaFileName {
        key_range: Key::from_i128(0x0)..Key::from_i128(0xFFFFFFFFFFFFFFFF),
        lsn_range: Lsn(0x00000000016B5A51)..Lsn(0x00000000016B5A61),
    });
@@ -797,7 +797,7 @@ mod test {
        /// Returns remote layer file name, suitable for use in assert_remote_files
        fn write_remote_layer(
            &self,
-            file_name: LayerName,
+            file_name: LayerFileName,
            gen: Generation,
        ) -> anyhow::Result<String> {
            let tenant_shard_id = self.harness.tenant_shard_id;
@@ -952,7 +952,7 @@ mod test {
        let client = ctx.deletion_queue.new_client();
        client.recover(HashMap::new())?;

-        let layer_file_name_1: LayerName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap();
+        let layer_file_name_1: LayerFileName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap();
        let tenant_shard_id = ctx.harness.tenant_shard_id;

        let content: Vec<u8> = "victim1 contents".into();
--- a/pageserver/src/deletion_queue/list_writer.rs
+++ b/pageserver/src/deletion_queue/list_writer.rs
@@ -34,7 +34,7 @@ use crate::deletion_queue::TEMP_SUFFIX;
 use crate::metrics;
 use crate::tenant::remote_timeline_client::remote_layer_path;
 use crate::tenant::remote_timeline_client::LayerFileMetadata;
-use crate::tenant::storage_layer::LayerName;
+use crate::tenant::storage_layer::LayerFileName;
 use crate::virtual_file::on_fatal_io_error;
 use crate::virtual_file::MaybeFatalIo;

@@ -59,7 +59,7 @@ pub(super) struct DeletionOp {
    // `layers` and `objects` are both just lists of objects.  `layers` is used if you do not
    // have a config object handy to project it to a remote key, and need the consuming worker
    // to do it for you.
-    pub(super) layers: Vec<(LayerName, LayerFileMetadata)>,
+    pub(super) layers: Vec<(LayerFileName, LayerFileMetadata)>,
    pub(super) objects: Vec<RemotePath>,

    /// The _current_ generation of the Tenant shard attachment in which we are enqueuing
--- a/pageserver/src/disk_usage_eviction_task.rs
+++ b/pageserver/src/disk_usage_eviction_task.rs
@@ -64,7 +64,7 @@ use crate::{
        mgr::TenantManager,
        remote_timeline_client::LayerFileMetadata,
        secondary::SecondaryTenant,
-        storage_layer::{AsLayerDesc, EvictionError, Layer, LayerName},
+        storage_layer::{AsLayerDesc, EvictionError, Layer, LayerFileName},
    },
 };

@@ -540,12 +540,7 @@ pub(crate) async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
                    js.spawn(async move {
                        layer
                            .secondary_tenant
-                            .evict_layer(
-                                tenant_manager.get_conf(),
-                                layer.timeline_id,
-                                layer.name,
-                                layer.metadata,
-                            )
+                            .evict_layer(tenant_manager.get_conf(), layer.timeline_id, layer.name)
                            .await;
                        Ok(file_size)
                    });
@@ -604,7 +599,7 @@ pub(crate) async fn disk_usage_eviction_task_iteration_impl<U: Usage>(
 pub(crate) struct EvictionSecondaryLayer {
    pub(crate) secondary_tenant: Arc<SecondaryTenant>,
    pub(crate) timeline_id: TimelineId,
-    pub(crate) name: LayerName,
+    pub(crate) name: LayerFileName,
    pub(crate) metadata: LayerFileMetadata,
 }

@@ -637,9 +632,9 @@ impl EvictionLayer {
        }
    }

-    pub(crate) fn get_name(&self) -> LayerName {
+    pub(crate) fn get_name(&self) -> LayerFileName {
        match self {
-            Self::Attached(l) => l.layer_desc().layer_name(),
+            Self::Attached(l) => l.layer_desc().filename(),
            Self::Secondary(sl) => sl.name.clone(),
        }
    }
--- a/pageserver/src/http/openapi_spec.yml
+++ b/pageserver/src/http/openapi_spec.yml
@@ -420,6 +420,25 @@ paths:
          description: Tenant scheduled to load successfully

  /v1/tenant/{tenant_id}/synthetic_size:
+    parameters:
+      - name: tenant_id
+        in: path
+        required: true
+        schema:
+          type: string
+    get:
+      description: |
+        Calculate tenant's synthetic size
+      responses:
+        "200":
+          description: Tenant's synthetic size
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/SyntheticSizeResponse"
+
+  # This route has no handler. TODO: remove?
+  /v1/tenant/{tenant_id}/size:
    parameters:
      - name: tenant_id
        in: path
@@ -449,9 +468,19 @@ paths:
          content:
            application/json:
              schema:
-                $ref: "#/components/schemas/SyntheticSizeResponse"
-            text/html:
-              description: SVG representation of the tenant and it's timelines.
+                type: object
+                required:
+                  - id
+                  - size
+                properties:
+                  id:
+                    type: string
+                    format: hex
+                  size:
+                    type: integer
+                    nullable: true
+                    description: |
+                      Size metric in bytes or null if inputs_only=true was given.
        "401":
          description: Unauthorized Error
          content:
@@ -753,6 +782,9 @@ components:
      required:
        - mode
      properties:
+        tenant_id:
+          type: string
+          description: Not used, scheduled for removal.
        mode:
          type: string
          enum: ["AttachedSingle", "AttachedMulti", "AttachedStale", "Secondary", "Detached"]
@@ -900,9 +932,6 @@ components:
          format: hex
        size:
          type: integer
-          nullable: true
-          description: |
-            Size metric in bytes or null if inputs_only=true was given.
        segment_sizes:
          type: array
          items:
--- a/pageserver/src/http/routes.rs
+++ b/pageserver/src/http/routes.rs
@@ -63,7 +63,6 @@ use crate::tenant::remote_timeline_client::list_remote_timelines;
 use crate::tenant::secondary::SecondaryController;
 use crate::tenant::size::ModelInputs;
 use crate::tenant::storage_layer::LayerAccessStatsReset;
-use crate::tenant::storage_layer::LayerName;
 use crate::tenant::timeline::CompactFlags;
 use crate::tenant::timeline::Timeline;
 use crate::tenant::SpawnMode;
@@ -1229,15 +1228,13 @@ async fn layer_download_handler(
    let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
    let layer_file_name = get_request_param(&request, "layer_file_name")?;
    check_permission(&request, Some(tenant_shard_id.tenant_id))?;
-    let layer_name = LayerName::from_str(layer_file_name)
-        .map_err(|s| ApiError::BadRequest(anyhow::anyhow!(s)))?;
    let state = get_state(&request);

    let timeline =
        active_timeline_of_active_tenant(&state.tenant_manager, tenant_shard_id, timeline_id)
            .await?;
    let downloaded = timeline
-        .download_layer(&layer_name)
+        .download_layer(layer_file_name)
        .await
        .map_err(ApiError::InternalServerError)?;

@@ -1261,14 +1258,11 @@ async fn evict_timeline_layer_handler(
    let layer_file_name = get_request_param(&request, "layer_file_name")?;
    let state = get_state(&request);

-    let layer_name = LayerName::from_str(layer_file_name)
-        .map_err(|s| ApiError::BadRequest(anyhow::anyhow!(s)))?;
-
    let timeline =
        active_timeline_of_active_tenant(&state.tenant_manager, tenant_shard_id, timeline_id)
            .await?;
    let evicted = timeline
-        .evict_layer(&layer_name)
+        .evict_layer(layer_file_name)
        .await
        .map_err(ApiError::InternalServerError)?;

@@ -1833,75 +1827,6 @@ async fn timeline_download_remote_layers_handler_get(
    json_response(StatusCode::OK, info)
 }

-async fn timeline_detach_ancestor_handler(
-    request: Request<Body>,
-    _cancel: CancellationToken,
-) -> Result<Response<Body>, ApiError> {
-    use crate::tenant::timeline::detach_ancestor::Options;
-    let tenant_shard_id: TenantShardId = parse_request_param(&request, "tenant_shard_id")?;
-    check_permission(&request, Some(tenant_shard_id.tenant_id))?;
-    let timeline_id: TimelineId = parse_request_param(&request, "timeline_id")?;
-
-    let span = tracing::info_span!("detach_ancestor", tenant_id=%tenant_shard_id.tenant_id, shard_id=%tenant_shard_id.shard_slug(), %timeline_id);
-
-    async move {
-        let mut options = Options::default();
-
-        let rewrite_concurrency =
-            parse_query_param::<_, std::num::NonZeroUsize>(&request, "rewrite_concurrency")?;
-        let copy_concurrency =
-            parse_query_param::<_, std::num::NonZeroUsize>(&request, "copy_concurrency")?;
-
-        [
-            (&mut options.rewrite_concurrency, rewrite_concurrency),
-            (&mut options.copy_concurrency, copy_concurrency),
-        ]
-        .into_iter()
-        .filter_map(|(target, val)| val.map(|val| (target, val)))
-        .for_each(|(target, val)| *target = val);
-
-        let state = get_state(&request);
-
-        let tenant = state
-            .tenant_manager
-            .get_attached_tenant_shard(tenant_shard_id)?;
-
-        tenant.wait_to_become_active(ACTIVE_TENANT_TIMEOUT).await?;
-
-        let ctx = RequestContext::new(TaskKind::DetachAncestor, DownloadBehavior::Download);
-        let ctx = &ctx;
-
-        let timeline = tenant
-            .get_timeline(timeline_id, true)
-            .map_err(|e| ApiError::NotFound(e.into()))?;
-
-        let (_guard, prepared) = timeline
-            .prepare_to_detach_from_ancestor(&tenant, options, ctx)
-            .await
-            .map_err(|e| ApiError::InternalServerError(e.into()))?;
-
-        let res = state
-            .tenant_manager
-            .complete_detaching_timeline_ancestor(tenant_shard_id, timeline_id, prepared, ctx)
-            .await;
-
-        match res {
-            Ok(reparented_timelines) => {
-                let resp = pageserver_api::models::detach_ancestor::AncestorDetached {
-                    reparented_timelines,
-                };
-
-                json_response(StatusCode::OK, resp)
-            }
-            Err(e) => Err(ApiError::InternalServerError(
-                e.context("timeline detach completion"),
-            )),
-        }
-    }
-    .instrument(span)
-    .await
-}
-
 async fn deletion_queue_flush(
    r: Request<Body>,
    cancel: CancellationToken,
@@ -2235,27 +2160,6 @@ async fn secondary_download_handler(
    json_response(status, progress)
 }

-async fn secondary_status_handler(
-    request: Request<Body>,
-    _cancel: CancellationToken,
-) -> Result<Response<Body>, ApiError> {
-    let state = get_state(&request);
-    let tenant_shard_id: TenantShardId = parse_request_param(&request, "tenant_shard_id")?;
-
-    let Some(secondary_tenant) = state
-        .tenant_manager
-        .get_secondary_tenant_shard(tenant_shard_id)
-    else {
-        return Err(ApiError::NotFound(
-            anyhow::anyhow!("Shard {} not found", tenant_shard_id).into(),
-        ));
-    };
-
-    let progress = secondary_tenant.progress.lock().unwrap().clone();
-
-    json_response(StatusCode::OK, progress)
-}
-
 async fn handler_404(_: Request<Body>) -> Result<Response<Body>, ApiError> {
    json_response(
        StatusCode::NOT_FOUND,
@@ -2590,10 +2494,6 @@ pub fn make_router(
            "/v1/tenant/:tenant_shard_id/timeline/:timeline_id/download_remote_layers",
            |r| api_handler(r, timeline_download_remote_layers_handler_get),
        )
-        .put(
-            "/v1/tenant/:tenant_shard_id/timeline/:timeline_id/detach_ancestor",
-            |r| api_handler(r, timeline_detach_ancestor_handler),
-        )
        .delete("/v1/tenant/:tenant_shard_id/timeline/:timeline_id", |r| {
            api_handler(r, timeline_delete_handler)
        })
@@ -2621,9 +2521,6 @@ pub fn make_router(
        .put("/v1/deletion_queue/flush", |r| {
            api_handler(r, deletion_queue_flush)
        })
-        .get("/v1/tenant/:tenant_shard_id/secondary/status", |r| {
-            api_handler(r, secondary_status_handler)
-        })
        .post("/v1/tenant/:tenant_shard_id/secondary/download", |r| {
            api_handler(r, secondary_download_handler)
        })
--- a/pageserver/src/metrics.rs
+++ b/pageserver/src/metrics.rs
@@ -51,8 +51,8 @@ pub(crate) enum StorageTimeOperation {
    #[strum(serialize = "gc")]
    Gc,

-    #[strum(serialize = "find gc cutoffs")]
-    FindGcCutoffs,
+    #[strum(serialize = "update gc info")]
+    UpdateGcInfo,

    #[strum(serialize = "create tenant")]
    CreateTenant,
@@ -194,11 +194,6 @@ pub(crate) struct GetVectoredLatency {
    map: EnumMap<TaskKind, Option<Histogram>>,
 }

-#[allow(dead_code)]
-pub(crate) struct ScanLatency {
-    map: EnumMap<TaskKind, Option<Histogram>>,
-}
-
 impl GetVectoredLatency {
    // Only these task types perform vectored gets. Filter all other tasks out to reduce total
    // cardinality of the metric.
@@ -209,48 +204,6 @@ impl GetVectoredLatency {
    }
 }

-impl ScanLatency {
-    // Only these task types perform vectored gets. Filter all other tasks out to reduce total
-    // cardinality of the metric.
-    const TRACKED_TASK_KINDS: [TaskKind; 1] = [TaskKind::PageRequestHandler];
-
-    pub(crate) fn for_task_kind(&self, task_kind: TaskKind) -> Option<&Histogram> {
-        self.map[task_kind].as_ref()
-    }
-}
-
-pub(crate) struct ScanLatencyOngoingRecording<'a> {
-    parent: &'a Histogram,
-    start: std::time::Instant,
-}
-
-impl<'a> ScanLatencyOngoingRecording<'a> {
-    pub(crate) fn start_recording(parent: &'a Histogram) -> ScanLatencyOngoingRecording<'a> {
-        let start = Instant::now();
-        ScanLatencyOngoingRecording { parent, start }
-    }
-
-    pub(crate) fn observe(self, throttled: Option<Duration>) {
-        let elapsed = self.start.elapsed();
-        let ex_throttled = if let Some(throttled) = throttled {
-            elapsed.checked_sub(throttled)
-        } else {
-            Some(elapsed)
-        };
-        if let Some(ex_throttled) = ex_throttled {
-            self.parent.observe(ex_throttled.as_secs_f64());
-        } else {
-            use utils::rate_limit::RateLimit;
-            static LOGGED: Lazy<Mutex<RateLimit>> =
-                Lazy::new(|| Mutex::new(RateLimit::new(Duration::from_secs(10))));
-            let mut rate_limit = LOGGED.lock().unwrap();
-            rate_limit.call(|| {
-                warn!("error deducting time spent throttled; this message is logged at a global rate limit");
-            });
-        }
-    }
-}
-
 pub(crate) static GET_VECTORED_LATENCY: Lazy<GetVectoredLatency> = Lazy::new(|| {
    let inner = register_histogram_vec!(
        "pageserver_get_vectored_seconds",
@@ -274,29 +227,6 @@ pub(crate) static GET_VECTORED_LATENCY: Lazy<GetVectoredLatency> = Lazy::new(||
    }
 });

-pub(crate) static SCAN_LATENCY: Lazy<ScanLatency> = Lazy::new(|| {
-    let inner = register_histogram_vec!(
-        "pageserver_scan_seconds",
-        "Time spent in scan, excluding time spent in timeline_get_throttle.",
-        &["task_kind"],
-        CRITICAL_OP_BUCKETS.into(),
-    )
-    .expect("failed to define a metric");
-
-    ScanLatency {
-        map: EnumMap::from_array(std::array::from_fn(|task_kind_idx| {
-            let task_kind = <TaskKind as enum_map::Enum>::from_usize(task_kind_idx);
-
-            if ScanLatency::TRACKED_TASK_KINDS.contains(&task_kind) {
-                let task_kind = task_kind.into();
-                Some(inner.with_label_values(&[task_kind]))
-            } else {
-                None
-            }
-        })),
-    }
-});
-
 pub(crate) struct PageCacheMetricsForTaskKind {
    pub read_accesses_materialized_page: IntCounter,
    pub read_accesses_immutable: IntCounter,
@@ -1512,80 +1442,29 @@ static REMOTE_TIMELINE_CLIENT_BYTES_FINISHED_COUNTER: Lazy<IntCounterVec> = Lazy
 });

 pub(crate) struct TenantManagerMetrics {
-    tenant_slots_attached: UIntGauge,
-    tenant_slots_secondary: UIntGauge,
-    tenant_slots_inprogress: UIntGauge,
+    pub(crate) tenant_slots: UIntGauge,
    pub(crate) tenant_slot_writes: IntCounter,
    pub(crate) unexpected_errors: IntCounter,
 }

-impl TenantManagerMetrics {
-    /// Helpers for tracking slots.  Note that these do not track the lifetime of TenantSlot objects
-    /// exactly: they track the lifetime of the slots _in the tenant map_.
-    pub(crate) fn slot_inserted(&self, slot: &TenantSlot) {
-        match slot {
-            TenantSlot::Attached(_) => {
-                self.tenant_slots_attached.inc();
-            }
-            TenantSlot::Secondary(_) => {
-                self.tenant_slots_secondary.inc();
-            }
-            TenantSlot::InProgress(_) => {
-                self.tenant_slots_inprogress.inc();
-            }
-        }
-    }
-
-    pub(crate) fn slot_removed(&self, slot: &TenantSlot) {
-        match slot {
-            TenantSlot::Attached(_) => {
-                self.tenant_slots_attached.dec();
-            }
-            TenantSlot::Secondary(_) => {
-                self.tenant_slots_secondary.dec();
-            }
-            TenantSlot::InProgress(_) => {
-                self.tenant_slots_inprogress.dec();
-            }
-        }
-    }
-
-    #[cfg(all(debug_assertions, not(test)))]
-    pub(crate) fn slots_total(&self) -> u64 {
-        self.tenant_slots_attached.get()
-            + self.tenant_slots_secondary.get()
-            + self.tenant_slots_inprogress.get()
-    }
-}
-
 pub(crate) static TENANT_MANAGER: Lazy<TenantManagerMetrics> = Lazy::new(|| {
-    let tenant_slots = register_uint_gauge_vec!(
+    TenantManagerMetrics {
+    tenant_slots: register_uint_gauge!(
        "pageserver_tenant_manager_slots",
        "How many slots currently exist, including all attached, secondary and in-progress operations",
-        &["mode"]
    )
-    .expect("failed to define a metric");
-    TenantManagerMetrics {
-        tenant_slots_attached: tenant_slots
-            .get_metric_with_label_values(&["attached"])
-            .unwrap(),
-        tenant_slots_secondary: tenant_slots
-            .get_metric_with_label_values(&["secondary"])
-            .unwrap(),
-        tenant_slots_inprogress: tenant_slots
-            .get_metric_with_label_values(&["inprogress"])
-            .unwrap(),
-        tenant_slot_writes: register_int_counter!(
-            "pageserver_tenant_manager_slot_writes",
-            "Writes to a tenant slot, including all of create/attach/detach/delete"
-        )
-        .expect("failed to define a metric"),
-        unexpected_errors: register_int_counter!(
-            "pageserver_tenant_manager_unexpected_errors_total",
-            "Number of unexpected conditions encountered: nonzero value indicates a non-fatal bug."
-        )
-        .expect("failed to define a metric"),
-    }
+    .expect("failed to define a metric"),
+    tenant_slot_writes: register_int_counter!(
+        "pageserver_tenant_manager_slot_writes",
+        "Writes to a tenant slot, including all of create/attach/detach/delete"
+    )
+    .expect("failed to define a metric"),
+    unexpected_errors: register_int_counter!(
+        "pageserver_tenant_manager_unexpected_errors_total",
+        "Number of unexpected conditions encountered: nonzero value indicates a non-fatal bug."
+    )
+    .expect("failed to define a metric"),
+}
 });

 pub(crate) struct DeletionQueueMetrics {
@@ -2110,7 +1989,7 @@ pub(crate) struct TimelineMetrics {
    pub imitate_logical_size_histo: StorageTimeMetrics,
    pub load_layer_map_histo: StorageTimeMetrics,
    pub garbage_collect_histo: StorageTimeMetrics,
-    pub find_gc_cutoffs_histo: StorageTimeMetrics,
+    pub update_gc_info_histo: StorageTimeMetrics,
    pub last_record_gauge: IntGauge,
    resident_physical_size_gauge: UIntGauge,
    /// copy of LayeredTimeline.current_logical_size
@@ -2171,8 +2050,8 @@ impl TimelineMetrics {
            &shard_id,
            &timeline_id,
        );
-        let find_gc_cutoffs_histo = StorageTimeMetrics::new(
-            StorageTimeOperation::FindGcCutoffs,
+        let update_gc_info_histo = StorageTimeMetrics::new(
+            StorageTimeOperation::UpdateGcInfo,
            &tenant_id,
            &shard_id,
            &timeline_id,
@@ -2219,7 +2098,7 @@ impl TimelineMetrics {
            logical_size_histo,
            imitate_logical_size_histo,
            garbage_collect_histo,
-            find_gc_cutoffs_histo,
+            update_gc_info_histo,
            load_layer_map_histo,
            last_record_gauge,
            resident_physical_size_gauge,
@@ -2326,7 +2205,6 @@ use std::time::{Duration, Instant};

 use crate::context::{PageContentKind, RequestContext};
 use crate::task_mgr::TaskKind;
-use crate::tenant::mgr::TenantSlot;

 /// Maintain a per timeline gauge in addition to the global gauge.
 struct PerTimelineRemotePhysicalSizeGauge {
@@ -2929,8 +2807,6 @@ pub fn preinitialize_metrics() {
        &WALRECEIVER_CANDIDATES_REMOVED,
        &tokio_epoll_uring::THREAD_LOCAL_LAUNCH_FAILURES,
        &tokio_epoll_uring::THREAD_LOCAL_LAUNCH_SUCCESSES,
-        &REMOTE_ONDEMAND_DOWNLOADED_LAYERS,
-        &REMOTE_ONDEMAND_DOWNLOADED_BYTES,
    ]
    .into_iter()
    .for_each(|c| {
--- a/pageserver/src/pgdatadir_mapping.rs
+++ b/pageserver/src/pgdatadir_mapping.rs
@@ -10,9 +10,9 @@ use super::tenant::{PageReconstructError, Timeline};
 use crate::context::RequestContext;
 use crate::keyspace::{KeySpace, KeySpaceAccum};
 use crate::metrics::WAL_INGEST;
+use crate::repository::*;
 use crate::span::debug_assert_current_span_has_tenant_and_timeline_id_no_shard_id;
 use crate::walrecord::NeonWalRecord;
-use crate::{aux_file, repository::*};
 use anyhow::{ensure, Context};
 use bytes::{Buf, Bytes, BytesMut};
 use enum_map::Enum;
@@ -24,7 +24,6 @@ use pageserver_api::key::{
    AUX_FILES_KEY, CHECKPOINT_KEY, CONTROLFILE_KEY, DBDIR_KEY, TWOPHASEDIR_KEY,
 };
 use pageserver_api::keyspace::SparseKeySpace;
-use pageserver_api::models::AuxFilePolicy;
 use pageserver_api::reltag::{BlockNumber, RelTag, SlruKind};
 use postgres_ffi::relfile_utils::{FSM_FORKNUM, VISIBILITYMAP_FORKNUM};
 use postgres_ffi::BLCKSZ;
@@ -280,7 +279,7 @@ impl Timeline {

        match RelDirectory::des(&buf).context("deserialization failure") {
            Ok(dir) => {
-                let exists = dir.rels.contains(&(tag.relnode, tag.forknum));
+                let exists = dir.rels.get(&(tag.relnode, tag.forknum)).is_some();
                Ok(exists)
            }
            Err(e) => Err(PageReconstructError::from(e)),
@@ -380,7 +379,7 @@ impl Timeline {

        match SlruSegmentDirectory::des(&buf).context("deserialization failure") {
            Ok(dir) => {
-                let exists = dir.segments.contains(&segno);
+                let exists = dir.segments.get(&segno).is_some();
                Ok(exists)
            }
            Err(e) => Err(PageReconstructError::from(e)),
@@ -671,7 +670,7 @@ impl Timeline {
        self.get(CHECKPOINT_KEY, lsn, ctx).await
    }

-    async fn list_aux_files_v1(
+    pub(crate) async fn list_aux_files(
        &self,
        lsn: Lsn,
        ctx: &RequestContext,
@@ -689,63 +688,6 @@ impl Timeline {
        }
    }

-    async fn list_aux_files_v2(
-        &self,
-        lsn: Lsn,
-        ctx: &RequestContext,
-    ) -> Result<HashMap<String, Bytes>, PageReconstructError> {
-        let kv = self
-            .scan(KeySpace::single(Key::metadata_aux_key_range()), lsn, ctx)
-            .await
-            .context("scan")?;
-        let mut result = HashMap::new();
-        for (_, v) in kv {
-            let v = v.context("get value")?;
-            let v = aux_file::decode_file_value_bytes(&v).context("value decode")?;
-            for (fname, content) in v {
-                result.insert(fname, content);
-            }
-        }
-        Ok(result)
-    }
-
-    pub(crate) async fn list_aux_files(
-        &self,
-        lsn: Lsn,
-        ctx: &RequestContext,
-    ) -> Result<HashMap<String, Bytes>, PageReconstructError> {
-        match self.get_switch_aux_file_policy() {
-            AuxFilePolicy::V1 => self.list_aux_files_v1(lsn, ctx).await,
-            AuxFilePolicy::V2 => self.list_aux_files_v2(lsn, ctx).await,
-            AuxFilePolicy::CrossValidation => {
-                let v1_result = self.list_aux_files_v1(lsn, ctx).await;
-                let v2_result = self.list_aux_files_v2(lsn, ctx).await;
-                match (v1_result, v2_result) {
-                    (Ok(v1), Ok(v2)) => {
-                        if v1 != v2 {
-                            tracing::error!(
-                                "unmatched aux file v1 v2 result:\nv1 {v1:?}\nv2 {v2:?}"
-                            );
-                            return Err(PageReconstructError::Other(anyhow::anyhow!(
-                                "unmatched aux file v1 v2 result"
-                            )));
-                        }
-                        Ok(v1)
-                    }
-                    (Ok(_), Err(v2)) => {
-                        tracing::error!("aux file v1 returns Ok while aux file v2 returns an err");
-                        Err(v2)
-                    }
-                    (Err(v1), Ok(_)) => {
-                        tracing::error!("aux file v2 returns Ok while aux file v1 returns an err");
-                        Err(v1)
-                    }
-                    (Err(_), Err(v2)) => Err(v2),
-                }
-            }
-        }
-    }
-
    /// Does the same as get_current_logical_size but counted on demand.
    /// Used to initialize the logical size tracking on startup.
    ///
@@ -1201,22 +1143,21 @@ impl<'a> DatadirModification<'a> {
        let mut dbdir = DbDirectory::des(&self.get(DBDIR_KEY, ctx).await.context("read db")?)
            .context("deserialize db")?;
        let rel_dir_key = rel_dir_to_key(rel.spcnode, rel.dbnode);
-        let mut rel_dir =
-            if let hash_map::Entry::Vacant(e) = dbdir.dbdirs.entry((rel.spcnode, rel.dbnode)) {
-                // Didn't exist. Update dbdir
-                e.insert(false);
-                let buf = DbDirectory::ser(&dbdir).context("serialize db")?;
-                self.pending_directory_entries
-                    .push((DirectoryKind::Db, dbdir.dbdirs.len()));
-                self.put(DBDIR_KEY, Value::Image(buf.into()));
+        let mut rel_dir = if dbdir.dbdirs.get(&(rel.spcnode, rel.dbnode)).is_none() {
+            // Didn't exist. Update dbdir
+            dbdir.dbdirs.insert((rel.spcnode, rel.dbnode), false);
+            let buf = DbDirectory::ser(&dbdir).context("serialize db")?;
+            self.pending_directory_entries
+                .push((DirectoryKind::Db, dbdir.dbdirs.len()));
+            self.put(DBDIR_KEY, Value::Image(buf.into()));

-                // and create the RelDirectory
-                RelDirectory::default()
-            } else {
-                // reldir already exists, fetch it
-                RelDirectory::des(&self.get(rel_dir_key, ctx).await.context("read db")?)
-                    .context("deserialize db")?
-            };
+            // and create the RelDirectory
+            RelDirectory::default()
+        } else {
+            // reldir already exists, fetch it
+            RelDirectory::des(&self.get(rel_dir_key, ctx).await.context("read db")?)
+                .context("deserialize db")?
+        };

        // Add the new relation to the rel directory entry, and write it back
        if !rel_dir.rels.insert((rel.relnode, rel.forknum)) {
@@ -1447,9 +1388,6 @@ impl<'a> DatadirModification<'a> {
    }

    pub fn init_aux_dir(&mut self) -> anyhow::Result<()> {
-        if let AuxFilePolicy::V2 = self.tline.get_switch_aux_file_policy() {
-            return Ok(());
-        }
        let buf = AuxFilesDirectory::ser(&AuxFilesDirectory {
            files: HashMap::new(),
        })?;
@@ -1465,122 +1403,90 @@ impl<'a> DatadirModification<'a> {
        content: &[u8],
        ctx: &RequestContext,
    ) -> anyhow::Result<()> {
-        let policy = self.tline.get_switch_aux_file_policy();
-        if let AuxFilePolicy::V2 | AuxFilePolicy::CrossValidation = policy {
-            let key = aux_file::encode_aux_file_key(path);
-            // retrieve the key from the engine
-            let old_val = match self.get(key, ctx).await {
-                Ok(val) => Some(val),
-                Err(PageReconstructError::MissingKey(_)) => None,
-                Err(e) => return Err(e.into()),
-            };
-            let files = if let Some(ref old_val) = old_val {
-                aux_file::decode_file_value(old_val)?
-            } else {
-                Vec::new()
-            };
-            let new_files = if content.is_empty() {
-                files
-                    .into_iter()
-                    .filter(|(p, _)| &path != p)
-                    .collect::<Vec<_>>()
-            } else {
-                files
-                    .into_iter()
-                    .filter(|(p, _)| &path != p)
-                    .chain(std::iter::once((path, content)))
-                    .collect::<Vec<_>>()
-            };
-            let new_val = aux_file::encode_file_value(&new_files)?;
-            self.put(key, Value::Image(new_val.into()));
-        }
+        let file_path = path.to_string();
+        let content = if content.is_empty() {
+            None
+        } else {
+            Some(Bytes::copy_from_slice(content))
+        };

-        if let AuxFilePolicy::V1 | AuxFilePolicy::CrossValidation = policy {
-            let file_path = path.to_string();
-            let content = if content.is_empty() {
-                None
+        let n_files;
+        let mut aux_files = self.tline.aux_files.lock().await;
+        if let Some(mut dir) = aux_files.dir.take() {
+            // We already updated aux files in `self`: emit a delta and update our latest value.
+            dir.upsert(file_path.clone(), content.clone());
+            n_files = dir.files.len();
+            if aux_files.n_deltas == MAX_AUX_FILE_DELTAS {
+                self.put(
+                    AUX_FILES_KEY,
+                    Value::Image(Bytes::from(
+                        AuxFilesDirectory::ser(&dir).context("serialize")?,
+                    )),
+                );
+                aux_files.n_deltas = 0;
            } else {
-                Some(Bytes::copy_from_slice(content))
-            };
+                self.put(
+                    AUX_FILES_KEY,
+                    Value::WalRecord(NeonWalRecord::AuxFile { file_path, content }),
+                );
+                aux_files.n_deltas += 1;
+            }
+            aux_files.dir = Some(dir);
+        } else {
+            // Check if the AUX_FILES_KEY is initialized
+            match self.get(AUX_FILES_KEY, ctx).await {
+                Ok(dir_bytes) => {
+                    let mut dir = AuxFilesDirectory::des(&dir_bytes)?;
+                    // Key is already set, we may append a delta
+                    self.put(
+                        AUX_FILES_KEY,
+                        Value::WalRecord(NeonWalRecord::AuxFile {
+                            file_path: file_path.clone(),
+                            content: content.clone(),
+                        }),
+                    );
+                    dir.upsert(file_path, content);
+                    n_files = dir.files.len();
+                    aux_files.dir = Some(dir);
+                }
+                Err(
+                    e @ (PageReconstructError::AncestorStopping(_)
+                    | PageReconstructError::Cancelled
+                    | PageReconstructError::AncestorLsnTimeout(_)),
+                ) => {
+                    // Important that we do not interpret a shutdown error as "not found" and thereby
+                    // reset the map.
+                    return Err(e.into());
+                }
+                // Note: we added missing key error variant in https://github.com/neondatabase/neon/pull/7393 but
+                // the original code assumes all other errors are missing keys. Therefore, we keep the code path
+                // the same for now, though in theory, we should only match the `MissingKey` variant.
+                Err(
+                    PageReconstructError::Other(_)
+                    | PageReconstructError::WalRedo(_)
+                    | PageReconstructError::MissingKey { .. },
+                ) => {
+                    // Key is missing, we must insert an image as the basis for subsequent deltas.

-            let n_files;
-            let mut aux_files = self.tline.aux_files.lock().await;
-            if let Some(mut dir) = aux_files.dir.take() {
-                // We already updated aux files in `self`: emit a delta and update our latest value.
-                dir.upsert(file_path.clone(), content.clone());
-                n_files = dir.files.len();
-                if aux_files.n_deltas == MAX_AUX_FILE_DELTAS {
+                    let mut dir = AuxFilesDirectory {
+                        files: HashMap::new(),
+                    };
+                    dir.upsert(file_path, content);
                    self.put(
                        AUX_FILES_KEY,
                        Value::Image(Bytes::from(
                            AuxFilesDirectory::ser(&dir).context("serialize")?,
                        )),
                    );
-                    aux_files.n_deltas = 0;
-                } else {
-                    self.put(
-                        AUX_FILES_KEY,
-                        Value::WalRecord(NeonWalRecord::AuxFile { file_path, content }),
-                    );
-                    aux_files.n_deltas += 1;
-                }
-                aux_files.dir = Some(dir);
-            } else {
-                // Check if the AUX_FILES_KEY is initialized
-                match self.get(AUX_FILES_KEY, ctx).await {
-                    Ok(dir_bytes) => {
-                        let mut dir = AuxFilesDirectory::des(&dir_bytes)?;
-                        // Key is already set, we may append a delta
-                        self.put(
-                            AUX_FILES_KEY,
-                            Value::WalRecord(NeonWalRecord::AuxFile {
-                                file_path: file_path.clone(),
-                                content: content.clone(),
-                            }),
-                        );
-                        dir.upsert(file_path, content);
-                        n_files = dir.files.len();
-                        aux_files.dir = Some(dir);
-                    }
-                    Err(
-                        e @ (PageReconstructError::AncestorStopping(_)
-                        | PageReconstructError::Cancelled
-                        | PageReconstructError::AncestorLsnTimeout(_)),
-                    ) => {
-                        // Important that we do not interpret a shutdown error as "not found" and thereby
-                        // reset the map.
-                        return Err(e.into());
-                    }
-                    // Note: we added missing key error variant in https://github.com/neondatabase/neon/pull/7393 but
-                    // the original code assumes all other errors are missing keys. Therefore, we keep the code path
-                    // the same for now, though in theory, we should only match the `MissingKey` variant.
-                    Err(
-                        PageReconstructError::Other(_)
-                        | PageReconstructError::WalRedo(_)
-                        | PageReconstructError::MissingKey { .. },
-                    ) => {
-                        // Key is missing, we must insert an image as the basis for subsequent deltas.
-
-                        let mut dir = AuxFilesDirectory {
-                            files: HashMap::new(),
-                        };
-                        dir.upsert(file_path, content);
-                        self.put(
-                            AUX_FILES_KEY,
-                            Value::Image(Bytes::from(
-                                AuxFilesDirectory::ser(&dir).context("serialize")?,
-                            )),
-                        );
-                        n_files = 1;
-                        aux_files.dir = Some(dir);
-                    }
+                    n_files = 1;
+                    aux_files.dir = Some(dir);
                }
            }
-
-            self.pending_directory_entries
-                .push((DirectoryKind::AuxFiles, n_files));
        }

+        self.pending_directory_entries
+            .push((DirectoryKind::AuxFiles, n_files));
+
        Ok(())
    }

--- a/pageserver/src/repository.rs
+++ b/pageserver/src/repository.rs
@@ -33,6 +33,7 @@ impl Value {
    }
 }

+#[cfg(test)]
 #[derive(Debug, PartialEq)]
 pub(crate) enum InvalidInput {
    TooShortValue,
@@ -41,8 +42,10 @@ pub(crate) enum InvalidInput {

 /// We could have a ValueRef where everything is `serde(borrow)`. Before implementing that, lets
 /// use this type for querying if a slice looks some particular way.
+#[cfg(test)]
 pub(crate) struct ValueBytes;

+#[cfg(test)]
 impl ValueBytes {
    pub(crate) fn will_init(raw: &[u8]) -> Result<bool, InvalidInput> {
        if raw.len() < 12 {
--- a/pageserver/src/task_mgr.rs
+++ b/pageserver/src/task_mgr.rs
@@ -319,9 +319,6 @@ pub enum TaskKind {
    // Eviction. One per timeline.
    Eviction,

-    // Ingest housekeeping (flushing ephemeral layers on time threshold or disk pressure)
-    IngestHousekeeping,
-
    /// See [`crate::disk_usage_eviction_task`].
    DiskUsageEviction,

@@ -366,12 +363,8 @@ pub enum TaskKind {

    EphemeralFilePreWarmPageCache,

-    LayerDownload,
-
    #[cfg(test)]
    UnitTest,
-
-    DetachAncestor,
 }

 #[derive(Default)]
--- a/pageserver/src/tenant.rs
+++ b/pageserver/src/tenant.rs
@@ -64,7 +64,6 @@ use self::timeline::uninit::UninitializedTimeline;
 use self::timeline::EvictionTaskTenantState;
 use self::timeline::TimelineResources;
 use self::timeline::WaitLsnError;
-use self::timeline::{GcCutoffs, GcInfo};
 use crate::config::PageServerConf;
 use crate::context::{DownloadBehavior, RequestContext};
 use crate::deletion_queue::DeletionQueueClient;
@@ -87,6 +86,7 @@ use crate::tenant::remote_timeline_client::INITDB_PATH;
 use crate::tenant::storage_layer::DeltaLayer;
 use crate::tenant::storage_layer::ImageLayer;
 use crate::InitializationOrder;
+use std::cmp::min;
 use std::collections::hash_map::Entry;
 use std::collections::BTreeSet;
 use std::collections::HashMap;
@@ -322,9 +322,6 @@ pub struct Tenant {
    /// All [`Tenant::timelines`] of a given [`Tenant`] instance share the same [`throttle::Throttle`] instance.
    pub(crate) timeline_get_throttle:
        Arc<throttle::Throttle<&'static crate::metrics::tenant_throttling::TimelineGet>>,
-
-    /// An ongoing timeline detach must be checked during attempts to GC or compact a timeline.
-    ongoing_timeline_detach: std::sync::Mutex<Option<(TimelineId, utils::completion::Barrier)>>,
 }

 impl std::fmt::Debug for Tenant {
@@ -1679,34 +1676,6 @@ impl Tenant {
        Ok(())
    }

-    // Call through to all timelines to freeze ephemeral layers if needed.  Usually
-    // this happens during ingest: this background housekeeping is for freezing layers
-    // that are open but haven't been written to for some time.
-    async fn ingest_housekeeping(&self) {
-        // Scan through the hashmap and collect a list of all the timelines,
-        // while holding the lock. Then drop the lock and actually perform the
-        // compactions.  We don't want to block everything else while the
-        // compaction runs.
-        let timelines = {
-            self.timelines
-                .lock()
-                .unwrap()
-                .values()
-                .filter_map(|timeline| {
-                    if timeline.is_active() {
-                        Some(timeline.clone())
-                    } else {
-                        None
-                    }
-                })
-                .collect::<Vec<_>>()
-        };
-
-        for timeline in &timelines {
-            timeline.maybe_freeze_ephemeral_layer().await;
-        }
-    }
-
    pub fn current_state(&self) -> TenantState {
        self.state.borrow().clone()
    }
@@ -2560,7 +2529,6 @@ impl Tenant {
                &crate::metrics::tenant_throttling::TIMELINE_GET,
            )),
            tenant_conf: Arc::new(ArcSwap::from_pointee(attached_conf)),
-            ongoing_timeline_detach: std::sync::Mutex::default(),
        }
    }

@@ -2844,48 +2812,7 @@ impl Tenant {
        cancel: &CancellationToken,
        ctx: &RequestContext,
    ) -> anyhow::Result<Vec<Arc<Timeline>>> {
-        // before taking the gc_cs lock, do the heavier weight finding of gc_cutoff points for
-        // currently visible timelines.
-        let timelines = self
-            .timelines
-            .lock()
-            .unwrap()
-            .values()
-            .filter(|tl| match target_timeline_id.as_ref() {
-                Some(target) => &tl.timeline_id == target,
-                None => true,
-            })
-            .cloned()
-            .collect::<Vec<_>>();
-
-        let mut gc_cutoffs: HashMap<TimelineId, GcCutoffs> =
-            HashMap::with_capacity(timelines.len());
-
-        for timeline in timelines.iter() {
-            let cutoff = timeline
-                .get_last_record_lsn()
-                .checked_sub(horizon)
-                .unwrap_or(Lsn(0));
-
-            let res = timeline.find_gc_cutoffs(cutoff, pitr, cancel, ctx).await;
-
-            match res {
-                Ok(cutoffs) => {
-                    let old = gc_cutoffs.insert(timeline.timeline_id, cutoffs);
-                    assert!(old.is_none());
-                }
-                Err(e) => {
-                    tracing::warn!(timeline_id = %timeline.timeline_id, "ignoring failure to find gc cutoffs: {e:#}");
-                }
-            }
-        }
-
-        if !self.is_active() {
-            anyhow::bail!("shutting down");
-        }
-
-        // grab mutex to prevent new timelines from being created here; avoid doing long operations
-        // because that will stall branch creation.
+        // grab mutex to prevent new timelines from being created here.
        let gc_cs = self.gc_cs.lock().await;

        // Scan all timelines. For each timeline, remember the timeline ID and
@@ -2947,6 +2874,11 @@ impl Tenant {
                }
            }

+            let cutoff = timeline
+                .get_last_record_lsn()
+                .checked_sub(horizon)
+                .unwrap_or(Lsn(0));
+
            let branchpoints: Vec<Lsn> = all_branchpoints
                .range((
                    Included((timeline_id, Lsn(0))),
@@ -2954,27 +2886,9 @@ impl Tenant {
                ))
                .map(|&x| x.1)
                .collect();
-
-            {
-                let mut target = timeline.gc_info.write().unwrap();
-
-                match gc_cutoffs.remove(&timeline_id) {
-                    Some(cutoffs) => {
-                        *target = GcInfo {
-                            retain_lsns: branchpoints,
-                            cutoffs,
-                        };
-                    }
-                    None => {
-                        // reasons for this being unavailable:
-                        // - this timeline was created while we were finding cutoffs
-                        // - lsn for timestamp search fails for this timeline repeatedly
-                        //
-                        // in both cases, refreshing the branchpoints is correct.
-                        target.retain_lsns = branchpoints;
-                    }
-                };
-            }
+            timeline
+                .update_gc_info(branchpoints, cutoff, pitr, cancel, ctx)
+                .await?;

            gc_timelines.push(timeline);
        }
@@ -3063,7 +2977,7 @@ impl Tenant {
        // and then the planned GC cutoff
        {
            let gc_info = src_timeline.gc_info.read().unwrap();
-            let cutoff = gc_info.min_cutoff();
+            let cutoff = min(gc_info.pitr_cutoff, gc_info.horizon_cutoff);
            if start_lsn < cutoff {
                return Err(CreateTimelineError::AncestorLsn(anyhow::anyhow!(
                    "invalid branch start lsn: less than planned GC cutoff {cutoff}"
@@ -3758,7 +3672,7 @@ pub(crate) mod harness {
                image_layer_creation_check_threshold: Some(
                    tenant_conf.image_layer_creation_check_threshold,
                ),
-                switch_aux_file_policy: Some(tenant_conf.switch_aux_file_policy),
+                switch_to_aux_file_v2: Some(tenant_conf.switch_to_aux_file_v2),
            }
        }
    }
@@ -3957,7 +3871,7 @@ mod tests {
    use crate::DEFAULT_PG_VERSION;
    use bytes::BytesMut;
    use hex_literal::hex;
-    use pageserver_api::key::{AUX_KEY_PREFIX, NON_INHERITED_RANGE};
+    use pageserver_api::key::NON_INHERITED_RANGE;
    use pageserver_api::keyspace::KeySpace;
    use pageserver_api::models::CompactionAlgorithm;
    use rand::{thread_rng, Rng};
@@ -4599,20 +4513,18 @@ mod tests {
    }

    async fn bulk_insert_compact_gc(
-        tenant: &Tenant,
-        timeline: &Arc<Timeline>,
+        timeline: Arc<Timeline>,
        ctx: &RequestContext,
        lsn: Lsn,
        repeat: usize,
        key_count: usize,
    ) -> anyhow::Result<()> {
        let compact = true;
-        bulk_insert_maybe_compact_gc(tenant, timeline, ctx, lsn, repeat, key_count, compact).await
+        bulk_insert_maybe_compact_gc(timeline, ctx, lsn, repeat, key_count, compact).await
    }

    async fn bulk_insert_maybe_compact_gc(
-        tenant: &Tenant,
-        timeline: &Arc<Timeline>,
+        timeline: Arc<Timeline>,
        ctx: &RequestContext,
        mut lsn: Lsn,
        repeat: usize,
@@ -4625,8 +4537,6 @@ mod tests {
        // Enforce that key range is monotonously increasing
        let mut keyspace = KeySpaceAccum::new();

-        let cancel = CancellationToken::new();
-
        for _ in 0..repeat {
            for _ in 0..key_count {
                test_key.field6 = blknum;
@@ -4648,19 +4558,24 @@ mod tests {
                blknum += 1;
            }

+            let cutoff = timeline.get_last_record_lsn();
+
+            timeline
+                .update_gc_info(
+                    Vec::new(),
+                    cutoff,
+                    Duration::ZERO,
+                    &CancellationToken::new(),
+                    ctx,
+                )
+                .await?;
            timeline.freeze_and_flush().await?;
            if compact {
-                // this requires timeline to be &Arc<Timeline>
-                timeline.compact(&cancel, EnumSet::empty(), ctx).await?;
+                timeline
+                    .compact(&CancellationToken::new(), EnumSet::empty(), ctx)
+                    .await?;
            }
-
-            // this doesn't really need to use the timeline_id target, but it is closer to what it
-            // originally was.
-            let res = tenant
-                .gc_iteration(Some(timeline.timeline_id), 0, Duration::ZERO, &cancel, ctx)
-                .await?;
-
-            assert_eq!(res.layers_removed, 0, "this never removes anything");
+            timeline.gc().await?;
        }

        Ok(())
@@ -4679,7 +4594,7 @@ mod tests {
            .await?;

        let lsn = Lsn(0x10);
-        bulk_insert_compact_gc(&tenant, &tline, &ctx, lsn, 50, 10000).await?;
+        bulk_insert_compact_gc(tline.clone(), &ctx, lsn, 50, 10000).await?;

        Ok(())
    }
@@ -4710,7 +4625,7 @@ mod tests {
            .await?;

        let lsn = Lsn(0x10);
-        bulk_insert_compact_gc(&tenant, &tline, &ctx, lsn, 50, 10000).await?;
+        bulk_insert_compact_gc(tline.clone(), &ctx, lsn, 50, 10000).await?;

        let guard = tline.layers.read().await;
        guard.layer_map().dump(true, &ctx).await?;
@@ -4823,7 +4738,15 @@ mod tests {
            .await;

        let images = vectored_res?;
-        assert!(images.is_empty());
+        let mut key = NON_INHERITED_RANGE.start;
+        while key < NON_INHERITED_RANGE.end {
+            assert!(matches!(
+                images[&key],
+                Err(PageReconstructError::MissingKey(_))
+            ));
+            key = key.next();
+        }
+
        Ok(())
    }

@@ -5156,7 +5079,6 @@ mod tests {
            .await?;

        const NUM_KEYS: usize = 1000;
-        let cancel = CancellationToken::new();

        let mut test_key = Key::from_hex("010000000033333333444444445500000000").unwrap();

@@ -5216,10 +5138,18 @@ mod tests {
            }

            // Perform a cycle of flush, and GC
-            tline.freeze_and_flush().await?;
-            tenant
-                .gc_iteration(Some(tline.timeline_id), 0, Duration::ZERO, &cancel, &ctx)
+            let cutoff = tline.get_last_record_lsn();
+            tline
+                .update_gc_info(
+                    Vec::new(),
+                    cutoff,
+                    Duration::ZERO,
+                    &CancellationToken::new(),
+                    &ctx,
+                )
                .await?;
+            tline.freeze_and_flush().await?;
+            tline.gc().await?;
        }

        Ok(())
@@ -5240,8 +5170,6 @@ mod tests {

        let mut keyspace = KeySpaceAccum::new();

-        let cancel = CancellationToken::new();
-
        // Track when each page was last modified. Used to assert that
        // a read sees the latest page version.
        let mut updated = [Lsn(0); NUM_KEYS];
@@ -5305,11 +5233,21 @@ mod tests {
            }

            // Perform a cycle of flush, compact, and GC
-            tline.freeze_and_flush().await?;
-            tline.compact(&cancel, EnumSet::empty(), &ctx).await?;
-            tenant
-                .gc_iteration(Some(tline.timeline_id), 0, Duration::ZERO, &cancel, &ctx)
+            let cutoff = tline.get_last_record_lsn();
+            tline
+                .update_gc_info(
+                    Vec::new(),
+                    cutoff,
+                    Duration::ZERO,
+                    &CancellationToken::new(),
+                    &ctx,
+                )
                .await?;
+            tline.freeze_and_flush().await?;
+            tline
+                .compact(&CancellationToken::new(), EnumSet::empty(), &ctx)
+                .await?;
+            tline.gc().await?;
        }

        Ok(())
@@ -5514,7 +5452,7 @@ mod tests {

        let lsn = Lsn(0x10);
        let compact = false;
-        bulk_insert_maybe_compact_gc(&tenant, &tline, &ctx, lsn, 50, 10000, compact).await?;
+        bulk_insert_maybe_compact_gc(tline.clone(), &ctx, lsn, 50, 10000, compact).await?;

        let test_key = Key::from_hex("010000000033333333444444445500000000").unwrap();
        let read_lsn = Lsn(u64::MAX - 1);
@@ -5524,108 +5462,4 @@ mod tests {

        Ok(())
    }
-
-    #[tokio::test]
-    async fn test_metadata_scan() -> anyhow::Result<()> {
-        let harness = TenantHarness::create("test_metadata_scan")?;
-        let (tenant, ctx) = harness.load().await;
-        let tline = tenant
-            .create_test_timeline(TIMELINE_ID, Lsn(0x10), DEFAULT_PG_VERSION, &ctx)
-            .await?;
-
-        const NUM_KEYS: usize = 1000;
-        const STEP: usize = 100; // random update + scan base_key + idx * STEP
-
-        let cancel = CancellationToken::new();
-
-        let mut base_key = Key::from_hex("000000000033333333444444445500000000").unwrap();
-        base_key.field1 = AUX_KEY_PREFIX;
-        let mut test_key = base_key;
-
-        // Track when each page was last modified. Used to assert that
-        // a read sees the latest page version.
-        let mut updated = [Lsn(0); NUM_KEYS];
-
-        let mut lsn = Lsn(0x10);
-        #[allow(clippy::needless_range_loop)]
-        for blknum in 0..NUM_KEYS {
-            lsn = Lsn(lsn.0 + 0x10);
-            test_key.field6 = (blknum * STEP) as u32;
-            let mut writer = tline.writer().await;
-            writer
-                .put(
-                    test_key,
-                    lsn,
-                    &Value::Image(test_img(&format!("{} at {}", blknum, lsn))),
-                    &ctx,
-                )
-                .await?;
-            writer.finish_write(lsn);
-            updated[blknum] = lsn;
-            drop(writer);
-        }
-
-        let keyspace = KeySpace::single(base_key..base_key.add((NUM_KEYS * STEP) as u32));
-
-        for _ in 0..10 {
-            // Read all the blocks
-            for (blknum, last_lsn) in updated.iter().enumerate() {
-                test_key.field6 = (blknum * STEP) as u32;
-                assert_eq!(
-                    tline.get(test_key, lsn, &ctx).await?,
-                    test_img(&format!("{} at {}", blknum, last_lsn))
-                );
-            }
-
-            let mut cnt = 0;
-            for (key, value) in tline
-                .get_vectored_impl(
-                    keyspace.clone(),
-                    lsn,
-                    ValuesReconstructState::default(),
-                    &ctx,
-                )
-                .await?
-            {
-                let blknum = key.field6 as usize;
-                let value = value?;
-                assert!(blknum % STEP == 0);
-                let blknum = blknum / STEP;
-                assert_eq!(
-                    value,
-                    test_img(&format!("{} at {}", blknum, updated[blknum]))
-                );
-                cnt += 1;
-            }
-
-            assert_eq!(cnt, NUM_KEYS);
-
-            for _ in 0..NUM_KEYS {
-                lsn = Lsn(lsn.0 + 0x10);
-                let blknum = thread_rng().gen_range(0..NUM_KEYS);
-                test_key.field6 = (blknum * STEP) as u32;
-                let mut writer = tline.writer().await;
-                writer
-                    .put(
-                        test_key,
-                        lsn,
-                        &Value::Image(test_img(&format!("{} at {}", blknum, lsn))),
-                        &ctx,
-                    )
-                    .await?;
-                writer.finish_write(lsn);
-                drop(writer);
-                updated[blknum] = lsn;
-            }
-
-            // Perform a cycle of flush, compact, and GC
-            tline.freeze_and_flush().await?;
-            tline.compact(&cancel, EnumSet::empty(), &ctx).await?;
-            tenant
-                .gc_iteration(Some(tline.timeline_id), 0, Duration::ZERO, &cancel, &ctx)
-                .await?;
-        }
-
-        Ok(())
-    }
 }
--- a/pageserver/src/tenant/blob_io.rs
+++ b/pageserver/src/tenant/blob_io.rs
@@ -130,9 +130,8 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
    async fn write_all_unbuffered<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        src_buf: B,
-        ctx: &RequestContext,
    ) -> (B::Buf, Result<(), Error>) {
-        let (src_buf, res) = self.inner.write_all(src_buf, ctx).await;
+        let (src_buf, res) = self.inner.write_all(src_buf).await;
        let nbytes = match res {
            Ok(nbytes) => nbytes,
            Err(e) => return (src_buf, Err(e)),
@@ -143,9 +142,9 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {

    #[inline(always)]
    /// Flushes the internal buffer to the underlying `VirtualFile`.
-    pub async fn flush_buffer(&mut self, ctx: &RequestContext) -> Result<(), Error> {
+    pub async fn flush_buffer(&mut self) -> Result<(), Error> {
        let buf = std::mem::take(&mut self.buf);
-        let (mut buf, res) = self.inner.write_all(buf, ctx).await;
+        let (mut buf, res) = self.inner.write_all(buf).await;
        res?;
        buf.clear();
        self.buf = buf;
@@ -166,11 +165,10 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        src_buf: B,
-        ctx: &RequestContext,
    ) -> (B::Buf, Result<(), Error>) {
        if !BUFFERED {
            assert!(self.buf.is_empty());
-            return self.write_all_unbuffered(src_buf, ctx).await;
+            return self.write_all_unbuffered(src_buf).await;
        }
        let remaining = Self::CAPACITY - self.buf.len();
        let src_buf_len = src_buf.bytes_init();
@@ -185,7 +183,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
        }
        // Then, if the buffer is full, flush it out
        if self.buf.len() == Self::CAPACITY {
-            if let Err(e) = self.flush_buffer(ctx).await {
+            if let Err(e) = self.flush_buffer().await {
                return (Slice::into_inner(src_buf), Err(e));
            }
        }
@@ -201,7 +199,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
                assert_eq!(copied, src_buf.len());
                Slice::into_inner(src_buf)
            } else {
-                let (src_buf, res) = self.write_all_unbuffered(src_buf, ctx).await;
+                let (src_buf, res) = self.write_all_unbuffered(src_buf).await;
                if let Err(e) = res {
                    return (src_buf, Err(e));
                }
@@ -218,7 +216,6 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
    pub async fn write_blob<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        srcbuf: B,
-        ctx: &RequestContext,
    ) -> (B::Buf, Result<u64, Error>) {
        let offset = self.offset;

@@ -230,7 +227,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
            if len < 128 {
                // Short blob. Write a 1-byte length header
                io_buf.put_u8(len as u8);
-                self.write_all(io_buf, ctx).await
+                self.write_all(io_buf).await
            } else {
                // Write a 4-byte length header
                if len > 0x7fff_ffff {
@@ -245,7 +242,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
                let mut len_buf = (len as u32).to_be_bytes();
                len_buf[0] |= 0x80;
                io_buf.extend_from_slice(&len_buf[..]);
-                self.write_all(io_buf, ctx).await
+                self.write_all(io_buf).await
            }
        }
        .await;
@@ -254,7 +251,7 @@ impl<const BUFFERED: bool> BlobWriter<BUFFERED> {
            Ok(_) => (),
            Err(e) => return (Slice::into_inner(srcbuf.slice(..)), Err(e)),
        }
-        let (srcbuf, res) = self.write_all(srcbuf, ctx).await;
+        let (srcbuf, res) = self.write_all(srcbuf).await;
        (srcbuf, res.map(|_| offset))
    }
 }
@@ -264,8 +261,8 @@ impl BlobWriter<true> {
    ///
    /// This function flushes the internal buffer before giving access
    /// to the underlying `VirtualFile`.
-    pub async fn into_inner(mut self, ctx: &RequestContext) -> Result<VirtualFile, Error> {
-        self.flush_buffer(ctx).await?;
+    pub async fn into_inner(mut self) -> Result<VirtualFile, Error> {
+        self.flush_buffer().await?;
        Ok(self.inner)
    }

@@ -302,16 +299,16 @@ mod tests {
            let file = VirtualFile::create(pathbuf.as_path()).await?;
            let mut wtr = BlobWriter::<BUFFERED>::new(file, 0);
            for blob in blobs.iter() {
-                let (_, res) = wtr.write_blob(blob.clone(), &ctx).await;
+                let (_, res) = wtr.write_blob(blob.clone()).await;
                let offs = res?;
                offsets.push(offs);
            }
            // Write out one page worth of zeros so that we can
            // read again with read_blk
-            let (_, res) = wtr.write_blob(vec![0; PAGE_SZ], &ctx).await;
+            let (_, res) = wtr.write_blob(vec![0; PAGE_SZ]).await;
            let offs = res?;
            println!("Writing final blob at offs={offs}");
-            wtr.flush_buffer(&ctx).await?;
+            wtr.flush_buffer().await?;
        }

        let file = VirtualFile::open(pathbuf.as_path()).await?;
--- a/pageserver/src/tenant/config.rs
+++ b/pageserver/src/tenant/config.rs
@@ -9,7 +9,6 @@
 //! may lead to a data loss.
 //!
 use anyhow::bail;
-use pageserver_api::models::AuxFilePolicy;
 use pageserver_api::models::CompactionAlgorithm;
 use pageserver_api::models::EvictionPolicy;
 use pageserver_api::models::{self, ThrottleConfig};
@@ -371,9 +370,9 @@ pub struct TenantConf {
    // Expresed in multiples of checkpoint distance.
    pub image_layer_creation_check_threshold: u8,

-    /// Switch to a new aux file policy. Switching this flag requires the user has not written any aux file into
+    /// Switch to aux file v2. Switching this flag requires the user has not written any aux file into
    /// the storage before, and this flag cannot be switched back. Otherwise there will be data corruptions.
-    pub switch_aux_file_policy: AuxFilePolicy,
+    pub switch_to_aux_file_v2: bool,
 }

 /// Same as TenantConf, but this struct preserves the information about
@@ -472,7 +471,7 @@ pub struct TenantConfOpt {

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

 impl TenantConfOpt {
@@ -530,9 +529,9 @@ impl TenantConfOpt {
            image_layer_creation_check_threshold: self
                .image_layer_creation_check_threshold
                .unwrap_or(global_conf.image_layer_creation_check_threshold),
-            switch_aux_file_policy: self
-                .switch_aux_file_policy
-                .unwrap_or(global_conf.switch_aux_file_policy),
+            switch_to_aux_file_v2: self
+                .switch_to_aux_file_v2
+                .unwrap_or(global_conf.switch_to_aux_file_v2),
        }
    }
 }
@@ -574,7 +573,7 @@ impl Default for TenantConf {
            lazy_slru_download: false,
            timeline_get_throttle: crate::tenant::throttle::Config::disabled(),
            image_layer_creation_check_threshold: DEFAULT_IMAGE_LAYER_CREATION_CHECK_THRESHOLD,
-            switch_aux_file_policy: AuxFilePolicy::V1,
+            switch_to_aux_file_v2: false,
        }
    }
 }
@@ -649,7 +648,7 @@ impl From<TenantConfOpt> for models::TenantConfig {
            lazy_slru_download: value.lazy_slru_download,
            timeline_get_throttle: value.timeline_get_throttle.map(ThrottleConfig::from),
            image_layer_creation_check_threshold: value.image_layer_creation_check_threshold,
-            switch_aux_file_policy: value.switch_aux_file_policy,
+            switch_to_aux_file_v2: value.switch_to_aux_file_v2,
        }
    }
 }
--- a/pageserver/src/tenant/delete.rs
+++ b/pageserver/src/tenant/delete.rs
@@ -585,20 +585,9 @@ impl DeleteTenantFlow {

                    // FIXME: we should not be modifying this from outside of mgr.rs.
                    // This will go away when we simplify deletion (https://github.com/neondatabase/neon/issues/5080)
-
-                    // Update stats
-                    match &removed {
-                        TenantsMapRemoveResult::Occupied(slot) => {
-                            crate::metrics::TENANT_MANAGER.slot_removed(slot);
-                        }
-                        TenantsMapRemoveResult::InProgress(barrier) => {
-                            crate::metrics::TENANT_MANAGER
-                                .slot_removed(&TenantSlot::InProgress(barrier.clone()));
-                        }
-                        TenantsMapRemoveResult::Vacant => {
-                            // Nothing changed in map, no metric update
-                        }
-                    }
+                    crate::metrics::TENANT_MANAGER
+                        .tenant_slots
+                        .set(locked.len() as u64);

                    match removed {
                        TenantsMapRemoveResult::Occupied(TenantSlot::Attached(tenant)) => {
--- a/pageserver/src/tenant/ephemeral_file.rs
+++ b/pageserver/src/tenant/ephemeral_file.rs
@@ -74,7 +74,7 @@ impl EphemeralFile {
    pub(crate) async fn write_blob(
        &mut self,
        srcbuf: &[u8],
-        ctx: &RequestContext,
+        _ctx: &RequestContext,
    ) -> Result<u64, io::Error> {
        let pos = self.rw.bytes_written();

@@ -83,15 +83,15 @@ impl EphemeralFile {
            // short one-byte length header
            let len_buf = [srcbuf.len() as u8];

-            self.rw.write_all_borrowed(&len_buf, ctx).await?;
+            self.rw.write_all_borrowed(&len_buf).await?;
        } else {
            let mut len_buf = u32::to_be_bytes(srcbuf.len() as u32);
            len_buf[0] |= 0x80;
-            self.rw.write_all_borrowed(&len_buf, ctx).await?;
+            self.rw.write_all_borrowed(&len_buf).await?;
        }

        // Write the payload
-        self.rw.write_all_borrowed(srcbuf, ctx).await?;
+        self.rw.write_all_borrowed(srcbuf).await?;

        Ok(pos)
    }
--- a/pageserver/src/tenant/ephemeral_file/page_caching.rs
+++ b/pageserver/src/tenant/ephemeral_file/page_caching.rs
@@ -35,14 +35,10 @@ impl RW {
        self.page_cache_file_id
    }

-    pub(crate) async fn write_all_borrowed(
-        &mut self,
-        srcbuf: &[u8],
-        ctx: &RequestContext,
-    ) -> Result<usize, io::Error> {
+    pub(crate) async fn write_all_borrowed(&mut self, srcbuf: &[u8]) -> Result<usize, io::Error> {
        // It doesn't make sense to proactively fill the page cache on the Pageserver write path
        // because Compute is unlikely to access recently written data.
-        self.rw.write_all_borrowed(srcbuf, ctx).await
+        self.rw.write_all_borrowed(srcbuf).await
    }

    pub(crate) fn bytes_written(&self) -> u64 {
@@ -138,7 +134,6 @@ impl crate::virtual_file::owned_buffers_io::write::OwnedAsyncWriter for PreWarmi
    >(
        &mut self,
        buf: B,
-        ctx: &RequestContext,
    ) -> std::io::Result<(usize, B::Buf)> {
        let buf = buf.slice(..);
        let saved_bounds = buf.bounds(); // save for reconstructing the Slice from iobuf after the IO is done
@@ -155,7 +150,7 @@ impl crate::virtual_file::owned_buffers_io::write::OwnedAsyncWriter for PreWarmi
        );

        // Do the IO.
-        let iobuf = match self.file.write_all(buf, ctx).await {
+        let iobuf = match self.file.write_all(buf).await {
            (iobuf, Ok(nwritten)) => {
                assert_eq!(nwritten, buflen);
                iobuf
--- a/pageserver/src/tenant/ephemeral_file/zero_padded_read_write.rs
+++ b/pageserver/src/tenant/ephemeral_file/zero_padded_read_write.rs
@@ -20,7 +20,6 @@
 mod zero_padded;

 use crate::{
-    context::RequestContext,
    page_cache::PAGE_SZ,
    virtual_file::owned_buffers_io::{
        self,
@@ -61,12 +60,8 @@ where
        self.buffered_writer.as_inner().as_inner()
    }

-    pub async fn write_all_borrowed(
-        &mut self,
-        buf: &[u8],
-        ctx: &RequestContext,
-    ) -> std::io::Result<usize> {
-        self.buffered_writer.write_buffered_borrowed(buf, ctx).await
+    pub async fn write_all_borrowed(&mut self, buf: &[u8]) -> std::io::Result<usize> {
+        self.buffered_writer.write_buffered_borrowed(buf).await
    }

    pub fn bytes_written(&self) -> u64 {
--- a/pageserver/src/tenant/layer_map.rs
+++ b/pageserver/src/tenant/layer_map.rs
@@ -588,7 +588,7 @@ impl LayerMap {
            let kr = Key::from_i128(current_key)..Key::from_i128(change_key);
            coverage.push((kr, current_val.take()));
            current_key = change_key;
-            current_val.clone_from(&change_val);
+            current_val = change_val.clone();
        }

        // Add the final interval
@@ -672,12 +672,12 @@ impl LayerMap {
        // Loop through the delta coverage and recurse on each part
        for (change_key, change_val) in version.delta_coverage.range(start..end) {
            // If there's a relevant delta in this part, add 1 and recurse down
-            if let Some(val) = &current_val {
+            if let Some(val) = current_val {
                if val.get_lsn_range().end > lsn.start {
                    let kr = Key::from_i128(current_key)..Key::from_i128(change_key);
                    let lr = lsn.start..val.get_lsn_range().start;
                    if !kr.is_empty() {
-                        let base_count = Self::is_reimage_worthy(val, key) as usize;
+                        let base_count = Self::is_reimage_worthy(&val, key) as usize;
                        let new_limit = limit.map(|l| l - base_count);
                        let max_stacked_deltas_underneath = self.count_deltas(&kr, &lr, new_limit);
                        max_stacked_deltas = std::cmp::max(
@@ -689,17 +689,17 @@ impl LayerMap {
            }

            current_key = change_key;
-            current_val.clone_from(&change_val);
+            current_val = change_val.clone();
        }

        // Consider the last part
-        if let Some(val) = &current_val {
+        if let Some(val) = current_val {
            if val.get_lsn_range().end > lsn.start {
                let kr = Key::from_i128(current_key)..Key::from_i128(end);
                let lr = lsn.start..val.get_lsn_range().start;

                if !kr.is_empty() {
-                    let base_count = Self::is_reimage_worthy(val, key) as usize;
+                    let base_count = Self::is_reimage_worthy(&val, key) as usize;
                    let new_limit = limit.map(|l| l - base_count);
                    let max_stacked_deltas_underneath = self.count_deltas(&kr, &lr, new_limit);
                    max_stacked_deltas = std::cmp::max(
--- a/pageserver/src/tenant/metadata.rs
+++ b/pageserver/src/tenant/metadata.rs
@@ -207,24 +207,6 @@ impl TimelineMetadata {
        self.body.ancestor_lsn
    }

-    /// When reparenting, the `ancestor_lsn` does not change.
-    pub fn reparent(&mut self, timeline: &TimelineId) {
-        assert!(self.body.ancestor_timeline.is_some());
-        // no assertion for redoing this: it's fine, we may have to repeat this multiple times over
-        self.body.ancestor_timeline = Some(*timeline);
-    }
-
-    pub fn detach_from_ancestor(&mut self, branchpoint: &(TimelineId, Lsn)) {
-        if let Some(ancestor) = self.body.ancestor_timeline {
-            assert_eq!(ancestor, branchpoint.0);
-        }
-        if self.body.ancestor_lsn != Lsn(0) {
-            assert_eq!(self.body.ancestor_lsn, branchpoint.1);
-        }
-        self.body.ancestor_timeline = None;
-        self.body.ancestor_lsn = Lsn(0);
-    }
-
    pub fn latest_gc_cutoff_lsn(&self) -> Lsn {
        self.body.latest_gc_cutoff_lsn
    }
--- a/pageserver/src/tenant/mgr.rs
+++ b/pageserver/src/tenant/mgr.rs
@@ -56,7 +56,6 @@ use utils::id::{TenantId, TimelineId};

 use super::delete::DeleteTenantError;
 use super::secondary::SecondaryTenant;
-use super::timeline::detach_ancestor::PreparedTimelineDetach;
 use super::TenantSharedResources;

 /// For a tenant that appears in TenantsMap, it may either be
@@ -247,7 +246,6 @@ impl TenantsMap {
        }
    }

-    #[cfg(all(debug_assertions, not(test)))]
    pub(crate) fn len(&self) -> usize {
        match self {
            TenantsMap::Initializing => 0,
@@ -748,7 +746,6 @@ pub async fn init_tenant_mgr(
            }
        };

-        METRICS.slot_inserted(&slot);
        tenants.insert(tenant_shard_id, slot);
    }

@@ -756,7 +753,7 @@ pub async fn init_tenant_mgr(

    let mut tenants_map = TENANTS.write().unwrap();
    assert!(matches!(&*tenants_map, &TenantsMap::Initializing));
-
+    METRICS.tenant_slots.set(tenants.len() as u64);
    *tenants_map = TenantsMap::Open(tenants);

    Ok(TenantManager {
@@ -827,14 +824,6 @@ fn tenant_spawn(
 async fn shutdown_all_tenants0(tenants: &std::sync::RwLock<TenantsMap>) {
    let mut join_set = JoinSet::new();

-    #[cfg(all(debug_assertions, not(test)))]
-    {
-        // Check that our metrics properly tracked the size of the tenants map.  This is a convenient location to check,
-        // as it happens implicitly at the end of tests etc.
-        let m = tenants.read().unwrap();
-        debug_assert_eq!(METRICS.slots_total(), m.len() as u64);
-    }
-
    // Atomically, 1. create the shutdown tasks and 2. prevent creation of new tenants.
    let (total_in_progress, total_attached) = {
        let mut m = tenants.write().unwrap();
@@ -2008,101 +1997,6 @@ impl TenantManager {
            })
            .collect())
    }
-
-    /// Completes an earlier prepared timeline detach ancestor.
-    pub(crate) async fn complete_detaching_timeline_ancestor(
-        &self,
-        tenant_shard_id: TenantShardId,
-        timeline_id: TimelineId,
-        prepared: PreparedTimelineDetach,
-        ctx: &RequestContext,
-    ) -> Result<Vec<TimelineId>, anyhow::Error> {
-        struct RevertOnDropSlot(Option<SlotGuard>);
-
-        impl Drop for RevertOnDropSlot {
-            fn drop(&mut self) {
-                if let Some(taken) = self.0.take() {
-                    taken.revert();
-                }
-            }
-        }
-
-        impl RevertOnDropSlot {
-            fn into_inner(mut self) -> SlotGuard {
-                self.0.take().unwrap()
-            }
-        }
-
-        impl std::ops::Deref for RevertOnDropSlot {
-            type Target = SlotGuard;
-
-            fn deref(&self) -> &Self::Target {
-                self.0.as_ref().unwrap()
-            }
-        }
-
-        let slot_guard = tenant_map_acquire_slot(&tenant_shard_id, TenantSlotAcquireMode::Any)?;
-        let slot_guard = RevertOnDropSlot(Some(slot_guard));
-
-        let tenant = {
-            let Some(old_slot) = slot_guard.get_old_value() else {
-                anyhow::bail!(
-                    "Tenant not found when trying to complete detaching timeline ancestor"
-                );
-            };
-
-            let Some(tenant) = old_slot.get_attached() else {
-                anyhow::bail!("Tenant is not in attached state");
-            };
-
-            if !tenant.is_active() {
-                anyhow::bail!("Tenant is not active");
-            }
-
-            tenant.clone()
-        };
-
-        let timeline = tenant.get_timeline(timeline_id, true)?;
-
-        let reparented = timeline
-            .complete_detaching_timeline_ancestor(&tenant, prepared, ctx)
-            .await?;
-
-        let mut slot_guard = slot_guard.into_inner();
-
-        let (_guard, progress) = utils::completion::channel();
-        match tenant.shutdown(progress, ShutdownMode::Hard).await {
-            Ok(()) => {
-                slot_guard.drop_old_value()?;
-            }
-            Err(_barrier) => {
-                slot_guard.revert();
-                // this really should not happen, at all, unless shutdown was already going?
-                anyhow::bail!("Cannot restart Tenant, already shutting down");
-            }
-        }
-
-        let tenant_path = self.conf.tenant_path(&tenant_shard_id);
-        let config = Tenant::load_tenant_config(self.conf, &tenant_shard_id)?;
-
-        let shard_identity = config.shard;
-        let tenant = tenant_spawn(
-            self.conf,
-            tenant_shard_id,
-            &tenant_path,
-            self.resources.clone(),
-            AttachedTenantConf::try_from(config)?,
-            shard_identity,
-            None,
-            self.tenants,
-            SpawnMode::Eager,
-            ctx,
-        )?;
-
-        slot_guard.upsert(TenantSlot::Attached(tenant))?;
-
-        Ok(reparented)
-    }
 }

 #[derive(Debug, thiserror::Error)]
@@ -2534,13 +2428,10 @@ impl SlotGuard {
                TenantsMap::Open(m) => m,
            };

-            METRICS.slot_inserted(&new_value);
-
            let replaced = m.insert(self.tenant_shard_id, new_value);
            self.upserted = true;
-            if let Some(replaced) = replaced.as_ref() {
-                METRICS.slot_removed(replaced);
-            }
+
+            METRICS.tenant_slots.set(m.len() as u64);

            replaced
        };
@@ -2650,13 +2541,9 @@ impl Drop for SlotGuard {
                }

                if self.old_value_is_shutdown() {
-                    METRICS.slot_removed(entry.get());
                    entry.remove();
                } else {
-                    let inserting = self.old_value.take().unwrap();
-                    METRICS.slot_inserted(&inserting);
-                    let replaced = entry.insert(inserting);
-                    METRICS.slot_removed(&replaced);
+                    entry.insert(self.old_value.take().unwrap());
                }
            }
            Entry::Vacant(_) => {
@@ -2667,6 +2554,8 @@ impl Drop for SlotGuard {
                );
            }
        }
+
+        METRICS.tenant_slots.set(m.len() as u64);
    }
 }

@@ -2746,9 +2635,7 @@ fn tenant_map_acquire_slot_impl(
            }
            _ => {
                let (completion, barrier) = utils::completion::channel();
-                let inserting = TenantSlot::InProgress(barrier);
-                METRICS.slot_inserted(&inserting);
-                v.insert(inserting);
+                v.insert(TenantSlot::InProgress(barrier));
                tracing::debug!("Vacant, inserted InProgress");
                Ok(SlotGuard::new(*tenant_shard_id, None, completion))
            }
@@ -2784,10 +2671,7 @@ fn tenant_map_acquire_slot_impl(
                _ => {
                    // Happy case: the slot was not in any state that violated our mode
                    let (completion, barrier) = utils::completion::channel();
-                    let in_progress = TenantSlot::InProgress(barrier);
-                    METRICS.slot_inserted(&in_progress);
-                    let old_value = o.insert(in_progress);
-                    METRICS.slot_removed(&old_value);
+                    let old_value = o.insert(TenantSlot::InProgress(barrier));
                    tracing::debug!("Occupied, replaced with InProgress");
                    Ok(SlotGuard::new(
                        *tenant_shard_id,
--- a/pageserver/src/tenant/remote_timeline_client.rs
+++ b/pageserver/src/tenant/remote_timeline_client.rs
@@ -210,7 +210,6 @@ use tracing::{debug, error, info, instrument, warn};
 use tracing::{info_span, Instrument};
 use utils::lsn::Lsn;

-use crate::context::RequestContext;
 use crate::deletion_queue::{DeletionQueueClient, DeletionQueueError};
 use crate::metrics::{
    MeasureRemoteOp, RemoteOpFileKind, RemoteOpKind, RemoteTimelineClientMetrics,
@@ -240,7 +239,7 @@ use utils::id::{TenantId, TimelineId};
 use self::index::IndexPart;

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

@@ -437,19 +436,6 @@ impl RemoteTimelineClient {
        }
    }

-    /// Returns true if this timeline was previously detached at this Lsn and the remote timeline
-    /// client is currently initialized.
-    pub(crate) fn is_previous_ancestor_lsn(&self, lsn: Lsn) -> bool {
-        // technically this is a dirty read, but given how timeline detach ancestor is implemented
-        // via tenant restart, the lineage has always been uploaded.
-        self.upload_queue
-            .lock()
-            .unwrap()
-            .initialized_mut()
-            .map(|uq| uq.latest_lineage.is_previous_ancestor_lsn(lsn))
-            .unwrap_or(false)
-    }
-
    fn update_remote_physical_size_gauge(&self, current_remote_index_part: Option<&IndexPart>) {
        let size: u64 = if let Some(current_remote_index_part) = current_remote_index_part {
            current_remote_index_part
@@ -516,10 +502,9 @@ impl RemoteTimelineClient {
    /// On success, returns the size of the downloaded file.
    pub async fn download_layer_file(
        &self,
-        layer_file_name: &LayerName,
+        layer_file_name: &LayerFileName,
        layer_metadata: &LayerFileMetadata,
        cancel: &CancellationToken,
-        ctx: &RequestContext,
    ) -> anyhow::Result<u64> {
        let downloaded_size = {
            let _unfinished_gauge_guard = self.metrics.call_begin(
@@ -537,7 +522,6 @@ impl RemoteTimelineClient {
                layer_file_name,
                layer_metadata,
                cancel,
-                ctx,
            )
            .measure_remote_op(
                RemoteOpFileKind::Layer,
@@ -583,7 +567,7 @@ impl RemoteTimelineClient {
        // ahead of what's _actually_ on the remote during index upload.
        upload_queue.latest_metadata = metadata.clone();

-        self.schedule_index_upload(upload_queue);
+        self.schedule_index_upload(upload_queue, upload_queue.latest_metadata.clone());

        Ok(())
    }
@@ -604,7 +588,7 @@ impl RemoteTimelineClient {

        upload_queue.latest_metadata.apply(update);

-        self.schedule_index_upload(upload_queue);
+        self.schedule_index_upload(upload_queue, upload_queue.latest_metadata.clone());

        Ok(())
    }
@@ -624,14 +608,18 @@ impl RemoteTimelineClient {
        let upload_queue = guard.initialized_mut()?;

        if upload_queue.latest_files_changes_since_metadata_upload_scheduled > 0 {
-            self.schedule_index_upload(upload_queue);
+            self.schedule_index_upload(upload_queue, upload_queue.latest_metadata.clone());
        }

        Ok(())
    }

    /// Launch an index-file upload operation in the background (internal function)
-    fn schedule_index_upload(self: &Arc<Self>, upload_queue: &mut UploadQueueInitialized) {
+    fn schedule_index_upload(
+        self: &Arc<Self>,
+        upload_queue: &mut UploadQueueInitialized,
+        metadata: TimelineMetadata,
+    ) {
        let disk_consistent_lsn = upload_queue.latest_metadata.disk_consistent_lsn();

        info!(
@@ -640,8 +628,12 @@ impl RemoteTimelineClient {
            upload_queue.latest_files_changes_since_metadata_upload_scheduled,
        );

-        let index_part = IndexPart::from(&*upload_queue);
-        let op = UploadOp::UploadMetadata(Box::new(index_part), disk_consistent_lsn);
+        let index_part = IndexPart::new(
+            upload_queue.latest_files.clone(),
+            disk_consistent_lsn,
+            metadata,
+        );
+        let op = UploadOp::UploadMetadata(index_part, disk_consistent_lsn);
        self.metric_begin(&op);
        upload_queue.queued_operations.push_back(op);
        upload_queue.latest_files_changes_since_metadata_upload_scheduled = 0;
@@ -650,67 +642,9 @@ impl RemoteTimelineClient {
        self.launch_queued_tasks(upload_queue);
    }

-    pub(crate) async fn schedule_reparenting_and_wait(
-        self: &Arc<Self>,
-        new_parent: &TimelineId,
-    ) -> anyhow::Result<()> {
-        // FIXME: because of how Timeline::schedule_uploads works when called from layer flushing
-        // and reads the in-memory part we cannot do the detaching like this
-        let receiver = {
-            let mut guard = self.upload_queue.lock().unwrap();
-            let upload_queue = guard.initialized_mut()?;
-
-            let Some(prev) = upload_queue.latest_metadata.ancestor_timeline() else {
-                return Err(anyhow::anyhow!(
-                    "cannot reparent without a current ancestor"
-                ));
-            };
-
-            upload_queue.latest_metadata.reparent(new_parent);
-            upload_queue.latest_lineage.record_previous_ancestor(&prev);
-
-            self.schedule_index_upload(upload_queue);
-
-            self.schedule_barrier0(upload_queue)
-        };
-
-        Self::wait_completion0(receiver).await
-    }
-
-    /// Schedules uploading a new version of `index_part.json` with the given layers added,
-    /// detaching from ancestor and waits for it to complete.
    ///
-    /// This is used with `Timeline::detach_ancestor` functionality.
-    pub(crate) async fn schedule_adding_existing_layers_to_index_detach_and_wait(
-        self: &Arc<Self>,
-        layers: &[Layer],
-        adopted: (TimelineId, Lsn),
-    ) -> anyhow::Result<()> {
-        let barrier = {
-            let mut guard = self.upload_queue.lock().unwrap();
-            let upload_queue = guard.initialized_mut()?;
-
-            upload_queue.latest_metadata.detach_from_ancestor(&adopted);
-            upload_queue.latest_lineage.record_detaching(&adopted);
-
-            for layer in layers {
-                upload_queue
-                    .latest_files
-                    .insert(layer.layer_desc().layer_name(), layer.metadata());
-            }
-
-            self.schedule_index_upload(upload_queue);
-
-            let barrier = self.schedule_barrier0(upload_queue);
-            self.launch_queued_tasks(upload_queue);
-            barrier
-        };
-
-        Self::wait_completion0(barrier).await
-    }
-
-    /// Launch an upload operation in the background; the file is added to be included in next
-    /// `index_part.json` upload.
+    /// Launch an upload operation in the background.
+    ///
    pub(crate) fn schedule_layer_file_upload(
        self: &Arc<Self>,
        layer: ResidentLayer,
@@ -732,15 +666,13 @@ impl RemoteTimelineClient {

        upload_queue
            .latest_files
-            .insert(layer.layer_desc().layer_name(), metadata.clone());
+            .insert(layer.layer_desc().filename(), metadata.clone());
        upload_queue.latest_files_changes_since_metadata_upload_scheduled += 1;

        info!(
-            gen=?metadata.generation,
-            shard=?metadata.shard,
-            "scheduled layer file upload {layer}",
+            "scheduled layer file upload {layer} gen={:?} shard={:?}",
+            metadata.generation, metadata.shard
        );
-
        let op = UploadOp::UploadLayer(layer, metadata);
        self.metric_begin(&op);
        upload_queue.queued_operations.push_back(op);
@@ -756,7 +688,7 @@ impl RemoteTimelineClient {
    /// successfully.
    pub fn schedule_layer_file_deletion(
        self: &Arc<Self>,
-        names: &[LayerName],
+        names: &[LayerFileName],
    ) -> anyhow::Result<()> {
        let mut guard = self.upload_queue.lock().unwrap();
        let upload_queue = guard.initialized_mut()?;
@@ -784,7 +716,7 @@ impl RemoteTimelineClient {
        // the layer files as "dangling". this is fine, at worst case we create work for the
        // scrubber.

-        let names = gc_layers.iter().map(|x| x.layer_desc().layer_name());
+        let names = gc_layers.iter().map(|x| x.layer_desc().filename());

        self.schedule_unlinking_of_layers_from_index_part0(upload_queue, names);

@@ -799,10 +731,14 @@ impl RemoteTimelineClient {
        self: &Arc<Self>,
        upload_queue: &mut UploadQueueInitialized,
        names: I,
-    ) -> Vec<(LayerName, LayerFileMetadata)>
+    ) -> Vec<(LayerFileName, LayerFileMetadata)>
    where
-        I: IntoIterator<Item = LayerName>,
+        I: IntoIterator<Item = LayerFileName>,
    {
+        // Deleting layers doesn't affect the values stored in TimelineMetadata,
+        // so we don't need update it. Just serialize it.
+        let metadata = upload_queue.latest_metadata.clone();
+
        // Decorate our list of names with each name's metadata, dropping
        // names that are unexpectedly missing from our metadata.  This metadata
        // is later used when physically deleting layers, to construct key paths.
@@ -841,7 +777,7 @@ impl RemoteTimelineClient {
        // index_part update, because that needs to be uploaded before we can actually delete the
        // files.
        if upload_queue.latest_files_changes_since_metadata_upload_scheduled > 0 {
-            self.schedule_index_upload(upload_queue);
+            self.schedule_index_upload(upload_queue, metadata);
        }

        with_metadata
@@ -851,7 +787,7 @@ impl RemoteTimelineClient {
    /// `index_part.json` with [`Self::schedule_gc_update`] or [`Self::schedule_compaction_update`].
    pub(crate) fn schedule_deletion_of_unlinked(
        self: &Arc<Self>,
-        layers: Vec<(LayerName, LayerFileMetadata)>,
+        layers: Vec<(LayerFileName, LayerFileMetadata)>,
    ) -> anyhow::Result<()> {
        let mut guard = self.upload_queue.lock().unwrap();
        let upload_queue = guard.initialized_mut()?;
@@ -864,7 +800,7 @@ impl RemoteTimelineClient {
    fn schedule_deletion_of_unlinked0(
        self: &Arc<Self>,
        upload_queue: &mut UploadQueueInitialized,
-        mut with_metadata: Vec<(LayerName, LayerFileMetadata)>,
+        mut with_metadata: Vec<(LayerFileName, LayerFileMetadata)>,
    ) {
        // Filter out any layers which were not created by this tenant shard.  These are
        // layers that originate from some ancestor shard after a split, and may still
@@ -933,7 +869,7 @@ impl RemoteTimelineClient {
            self.schedule_layer_file_upload0(upload_queue, layer.clone());
        }

-        let names = compacted_from.iter().map(|x| x.layer_desc().layer_name());
+        let names = compacted_from.iter().map(|x| x.layer_desc().filename());

        self.schedule_unlinking_of_layers_from_index_part0(upload_queue, names);
        self.launch_queued_tasks(upload_queue);
@@ -943,18 +879,12 @@ impl RemoteTimelineClient {

    /// Wait for all previously scheduled uploads/deletions to complete
    pub(crate) async fn wait_completion(self: &Arc<Self>) -> anyhow::Result<()> {
-        let receiver = {
+        let mut receiver = {
            let mut guard = self.upload_queue.lock().unwrap();
            let upload_queue = guard.initialized_mut()?;
            self.schedule_barrier0(upload_queue)
        };

-        Self::wait_completion0(receiver).await
-    }
-
-    async fn wait_completion0(
-        mut receiver: tokio::sync::watch::Receiver<()>,
-    ) -> anyhow::Result<()> {
        if receiver.changed().await.is_err() {
            anyhow::bail!("wait_completion aborted because upload queue was stopped");
        }
@@ -1070,7 +1000,8 @@ impl RemoteTimelineClient {
            let deleted_at = Utc::now().naive_utc();
            stopped.deleted_at = SetDeletedFlagProgress::InProgress(deleted_at);

-            let mut index_part = IndexPart::from(&stopped.upload_queue_for_deletion);
+            let mut index_part = IndexPart::try_from(&stopped.upload_queue_for_deletion)
+                .context("IndexPart serialize")?;
            index_part.deleted_at = Some(deleted_at);
            index_part
        };
@@ -1151,93 +1082,6 @@ impl RemoteTimelineClient {
        Ok(())
    }

-    /// Uploads the given layer **without** adding it to be part of a future `index_part.json` upload.
-    ///
-    /// This is not normally needed.
-    pub(crate) async fn upload_layer_file(
-        self: &Arc<Self>,
-        uploaded: &ResidentLayer,
-        cancel: &CancellationToken,
-    ) -> anyhow::Result<()> {
-        let remote_path = remote_layer_path(
-            &self.tenant_shard_id.tenant_id,
-            &self.timeline_id,
-            self.tenant_shard_id.to_index(),
-            &uploaded.layer_desc().layer_name(),
-            uploaded.metadata().generation,
-        );
-
-        backoff::retry(
-            || async {
-                upload::upload_timeline_layer(
-                    &self.storage_impl,
-                    uploaded.local_path(),
-                    &remote_path,
-                    uploaded.metadata().file_size(),
-                    cancel,
-                )
-                .await
-            },
-            TimeoutOrCancel::caused_by_cancel,
-            FAILED_UPLOAD_WARN_THRESHOLD,
-            FAILED_REMOTE_OP_RETRIES,
-            "upload a layer without adding it to latest files",
-            cancel,
-        )
-        .await
-        .ok_or_else(|| anyhow::Error::new(TimeoutOrCancel::Cancel))
-        .and_then(|x| x)
-        .context("upload a layer without adding it to latest files")
-    }
-
-    /// Copies the `adopted` remote existing layer to the remote path of `adopted_as`. The layer is
-    /// not added to be part of a future `index_part.json` upload.
-    pub(crate) async fn copy_timeline_layer(
-        self: &Arc<Self>,
-        adopted: &Layer,
-        adopted_as: &Layer,
-        cancel: &CancellationToken,
-    ) -> anyhow::Result<()> {
-        let source_remote_path = remote_layer_path(
-            &self.tenant_shard_id.tenant_id,
-            &adopted
-                .get_timeline_id()
-                .expect("Source timeline should be alive"),
-            self.tenant_shard_id.to_index(),
-            &adopted.layer_desc().layer_name(),
-            adopted.metadata().generation,
-        );
-
-        let target_remote_path = remote_layer_path(
-            &self.tenant_shard_id.tenant_id,
-            &self.timeline_id,
-            self.tenant_shard_id.to_index(),
-            &adopted_as.layer_desc().layer_name(),
-            adopted_as.metadata().generation,
-        );
-
-        backoff::retry(
-            || async {
-                upload::copy_timeline_layer(
-                    &self.storage_impl,
-                    &source_remote_path,
-                    &target_remote_path,
-                    cancel,
-                )
-                .await
-            },
-            TimeoutOrCancel::caused_by_cancel,
-            FAILED_UPLOAD_WARN_THRESHOLD,
-            FAILED_REMOTE_OP_RETRIES,
-            "copy timeline layer",
-            cancel,
-        )
-        .await
-        .ok_or_else(|| anyhow::Error::new(TimeoutOrCancel::Cancel))
-        .and_then(|x| x)
-        .context("remote copy timeline layer")
-    }
-
    async fn flush_deletion_queue(&self) -> Result<(), DeletionQueueError> {
        match tokio::time::timeout(
            DELETION_QUEUE_FLUSH_TIMEOUT,
@@ -1409,7 +1253,7 @@ impl RemoteTimelineClient {
        while let Some(next_op) = upload_queue.queued_operations.front() {
            // Can we run this task now?
            let can_run_now = match next_op {
-                UploadOp::UploadLayer(..) => {
+                UploadOp::UploadLayer(_, _) => {
                    // Can always be scheduled.
                    true
                }
@@ -1536,25 +1380,13 @@ impl RemoteTimelineClient {

            let upload_result: anyhow::Result<()> = match &task.op {
                UploadOp::UploadLayer(ref layer, ref layer_metadata) => {
-                    let local_path = layer.local_path();
-
-                    // We should only be uploading layers created by this `Tenant`'s lifetime, so
-                    // the metadata in the upload should always match our current generation.
-                    assert_eq!(layer_metadata.generation, self.generation);
-
-                    let remote_path = remote_layer_path(
-                        &self.tenant_shard_id.tenant_id,
-                        &self.timeline_id,
-                        layer_metadata.shard,
-                        &layer.layer_desc().layer_name(),
-                        layer_metadata.generation,
-                    );
-
+                    let path = layer.local_path();
                    upload::upload_timeline_layer(
+                        self.conf,
                        &self.storage_impl,
-                        local_path,
-                        &remote_path,
-                        layer_metadata.file_size(),
+                        path,
+                        layer_metadata,
+                        self.generation,
                        &self.cancel,
                    )
                    .measure_remote_op(
@@ -1830,7 +1662,6 @@ impl RemoteTimelineClient {
                        latest_files: initialized.latest_files.clone(),
                        latest_files_changes_since_metadata_upload_scheduled: 0,
                        latest_metadata: initialized.latest_metadata.clone(),
-                        latest_lineage: initialized.latest_lineage.clone(),
                        projected_remote_consistent_lsn: None,
                        visible_remote_consistent_lsn: initialized
                            .visible_remote_consistent_lsn
@@ -1916,14 +1747,14 @@ pub fn remote_layer_path(
    tenant_id: &TenantId,
    timeline_id: &TimelineId,
    shard: ShardIndex,
-    layer_file_name: &LayerName,
+    layer_file_name: &LayerFileName,
    generation: Generation,
 ) -> RemotePath {
    // Generation-aware key format
    let path = format!(
        "tenants/{tenant_id}{0}/{TIMELINES_SEGMENT_NAME}/{timeline_id}/{1}{2}",
        shard.get_suffix(),
-        layer_file_name,
+        layer_file_name.file_name(),
        generation.get_suffix()
    );

@@ -1984,6 +1815,29 @@ pub fn parse_remote_index_path(path: RemotePath) -> Option<Generation> {
    }
 }

+/// Files on the remote storage are stored with paths, relative to the workdir.
+/// That path includes in itself both tenant and timeline ids, allowing to have a unique remote storage path.
+///
+/// Errors if the path provided does not start from pageserver's workdir.
+pub fn remote_path(
+    conf: &PageServerConf,
+    local_path: &Utf8Path,
+    generation: Generation,
+) -> anyhow::Result<RemotePath> {
+    let stripped = local_path
+        .strip_prefix(&conf.workdir)
+        .context("Failed to strip workdir prefix")?;
+
+    let suffixed = format!("{0}{1}", stripped, generation.get_suffix());
+
+    RemotePath::new(Utf8Path::new(&suffixed)).with_context(|| {
+        format!(
+            "to resolve remote part of path {:?} for base {:?}",
+            local_path, conf.workdir
+        )
+    })
+}
+
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -1991,7 +1845,6 @@ mod tests {
        context::RequestContext,
        tenant::{
            harness::{TenantHarness, TIMELINE_ID},
-            storage_layer::layer::local_layer_path,
            Tenant, Timeline,
        },
        DEFAULT_PG_VERSION,
@@ -2020,8 +1873,8 @@ mod tests {
        TimelineMetadata::from_bytes(&metadata.to_bytes().unwrap()).unwrap()
    }

-    fn assert_file_list(a: &HashSet<LayerName>, b: &[&str]) {
-        let mut avec: Vec<String> = a.iter().map(|x| x.to_string()).collect();
+    fn assert_file_list(a: &HashSet<LayerFileName>, b: &[&str]) {
+        let mut avec: Vec<String> = a.iter().map(|x| x.file_name()).collect();
        avec.sort();

        let mut bvec = b.to_vec();
@@ -2147,7 +2000,7 @@ mod tests {
            .layer_metadata
            .keys()
            .map(|f| f.to_owned())
-            .collect::<HashSet<LayerName>>();
+            .collect::<HashSet<LayerFileName>>();
        let initial_layer = {
            assert!(initial_layers.len() == 1);
            initial_layers.into_iter().next().unwrap()
@@ -2173,21 +2026,12 @@ mod tests {
            ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59DA-00000000016B5A53".parse().unwrap(), dummy_contents("baz"))
        ]
        .into_iter()
-        .map(|(name, contents): (LayerName, Vec<u8>)| {
-
-            let local_path = local_layer_path(
-                harness.conf,
-                &timeline.tenant_shard_id,
-                &timeline.timeline_id,
-                &name,
-                &generation,
-            );
-            std::fs::write(&local_path, &contents).unwrap();
+        .map(|(name, contents): (LayerFileName, Vec<u8>)| {
+            std::fs::write(timeline_path.join(name.file_name()), &contents).unwrap();

            Layer::for_resident(
                harness.conf,
                &timeline,
-                local_path,
                name,
                LayerFileMetadata::new(contents.len() as u64, generation, shard),
            )
@@ -2254,9 +2098,9 @@ mod tests {
                .map(|f| f.to_owned())
                .collect(),
            &[
-                &initial_layer.to_string(),
-                &layers[0].layer_desc().layer_name().to_string(),
-                &layers[1].layer_desc().layer_name().to_string(),
+                &initial_layer.file_name(),
+                &layers[0].layer_desc().filename().file_name(),
+                &layers[1].layer_desc().filename().file_name(),
            ],
        );
        assert_eq!(index_part.metadata, metadata);
@@ -2270,7 +2114,7 @@ mod tests {
        // keep using schedule_layer_file_deletion because we don't have a way to wait for the
        // spawn_blocking started by the drop.
        client
-            .schedule_layer_file_deletion(&[layers[0].layer_desc().layer_name()])
+            .schedule_layer_file_deletion(&[layers[0].layer_desc().filename()])
            .unwrap();
        {
            let mut guard = client.upload_queue.lock().unwrap();
@@ -2288,9 +2132,9 @@ mod tests {
        }
        assert_remote_files(
            &[
-                &initial_layer.to_string(),
-                &layers[0].layer_desc().layer_name().to_string(),
-                &layers[1].layer_desc().layer_name().to_string(),
+                &initial_layer.file_name(),
+                &layers[0].layer_desc().filename().file_name(),
+                &layers[1].layer_desc().filename().file_name(),
                "index_part.json",
            ],
            &remote_timeline_dir,
@@ -2303,9 +2147,9 @@ mod tests {

        assert_remote_files(
            &[
-                &initial_layer.to_string(),
-                &layers[1].layer_desc().layer_name().to_string(),
-                &layers[2].layer_desc().layer_name().to_string(),
+                &initial_layer.file_name(),
+                &layers[1].layer_desc().filename().file_name(),
+                &layers[2].layer_desc().filename().file_name(),
                "index_part.json",
            ],
            &remote_timeline_dir,
@@ -2324,22 +2168,19 @@ mod tests {
            ..
        } = TestSetup::new("metrics").await.unwrap();
        let client = timeline.remote_client.as_ref().unwrap();
+        let timeline_path = harness.timeline_path(&TIMELINE_ID);

-        let layer_file_name_1: LayerName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap();
-        let local_path = local_layer_path(
-            harness.conf,
-            &timeline.tenant_shard_id,
-            &timeline.timeline_id,
-            &layer_file_name_1,
-            &harness.generation,
-        );
+        let layer_file_name_1: LayerFileName = "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000016B59D8-00000000016B5A51".parse().unwrap();
        let content_1 = dummy_contents("foo");
-        std::fs::write(&local_path, &content_1).unwrap();
+        std::fs::write(
+            timeline_path.join(layer_file_name_1.file_name()),
+            &content_1,
+        )
+        .unwrap();

        let layer_file_1 = Layer::for_resident(
            harness.conf,
            &timeline,
-            local_path,
            layer_file_name_1.clone(),
            LayerFileMetadata::new(content_1.len() as u64, harness.generation, harness.shard),
        );
@@ -2408,7 +2249,12 @@ mod tests {

    async fn inject_index_part(test_state: &TestSetup, generation: Generation) -> IndexPart {
        // An empty IndexPart, just sufficient to ensure deserialization will succeed
-        let example_index_part = IndexPart::example();
+        let example_metadata = TimelineMetadata::example();
+        let example_index_part = IndexPart::new(
+            HashMap::new(),
+            example_metadata.disk_consistent_lsn(),
+            example_metadata,
+        );

        let index_part_bytes = serde_json::to_vec(&example_index_part).unwrap();

--- a/pageserver/src/tenant/remote_timeline_client/download.rs
+++ b/pageserver/src/tenant/remote_timeline_client/download.rs
@@ -18,11 +18,9 @@ use tracing::warn;
 use utils::backoff;

 use crate::config::PageServerConf;
-use crate::context::RequestContext;
 use crate::span::debug_assert_current_span_has_tenant_and_timeline_id;
 use crate::tenant::remote_timeline_client::{remote_layer_path, remote_timelines_path};
-use crate::tenant::storage_layer::layer::local_layer_path;
-use crate::tenant::storage_layer::LayerName;
+use crate::tenant::storage_layer::LayerFileName;
 use crate::tenant::Generation;
 use crate::virtual_file::{on_fatal_io_error, MaybeFatalIo, VirtualFile};
 use crate::TEMP_FILE_SUFFIX;
@@ -42,27 +40,19 @@ use super::{
 /// in the metadata. (In the future, we might do more cross-checks, like CRC validation)
 ///
 /// Returns the size of the downloaded file.
-#[allow(clippy::too_many_arguments)]
 pub async fn download_layer_file<'a>(
    conf: &'static PageServerConf,
    storage: &'a GenericRemoteStorage,
    tenant_shard_id: TenantShardId,
    timeline_id: TimelineId,
-    layer_file_name: &'a LayerName,
+    layer_file_name: &'a LayerFileName,
    layer_metadata: &'a LayerFileMetadata,
    cancel: &CancellationToken,
-    ctx: &RequestContext,
 ) -> Result<u64, DownloadError> {
    debug_assert_current_span_has_tenant_and_timeline_id();

    let timeline_path = conf.timeline_path(&tenant_shard_id, &timeline_id);
-    let local_path = local_layer_path(
-        conf,
-        &tenant_shard_id,
-        &timeline_id,
-        layer_file_name,
-        &layer_metadata.generation,
-    );
+    let local_path = timeline_path.join(layer_file_name.file_name());

    let remote_path = remote_layer_path(
        &tenant_shard_id.tenant_id,
@@ -85,7 +75,7 @@ pub async fn download_layer_file<'a>(
    let temp_file_path = path_with_suffix_extension(&local_path, TEMP_DOWNLOAD_EXTENSION);

    let bytes_amount = download_retry(
-        || async { download_object(storage, &remote_path, &temp_file_path, cancel, ctx).await },
+        || async { download_object(storage, &remote_path, &temp_file_path, cancel).await },
        &format!("download {remote_path:?}"),
        cancel,
    )
@@ -143,7 +133,6 @@ async fn download_object<'a>(
    src_path: &RemotePath,
    dst_path: &Utf8PathBuf,
    cancel: &CancellationToken,
-    #[cfg_attr(target_os = "macos", allow(unused_variables))] ctx: &RequestContext,
 ) -> Result<u64, DownloadError> {
    let res = match crate::virtual_file::io_engine::get() {
        crate::virtual_file::io_engine::IoEngine::NotSet => panic!("unset"),
@@ -219,10 +208,10 @@ async fn download_object<'a>(
                            Err(e) => return Err(e),
                        };
                        buffered
-                            .write_buffered(tokio_epoll_uring::BoundedBuf::slice_full(chunk), ctx)
+                            .write_buffered(tokio_epoll_uring::BoundedBuf::slice_full(chunk))
                            .await?;
                    }
-                    let size_tracking = buffered.flush_and_into_inner(ctx).await?;
+                    let size_tracking = buffered.flush_and_into_inner().await?;
                    Ok(size_tracking.into_inner())
                }
                .await?;
--- a/pageserver/src/tenant/remote_timeline_client/index.rs
+++ b/pageserver/src/tenant/remote_timeline_client/index.rs
@@ -6,10 +6,10 @@ use std::collections::HashMap;

 use chrono::NaiveDateTime;
 use serde::{Deserialize, Serialize};
-use utils::id::TimelineId;
+use utils::bin_ser::SerializeError;

 use crate::tenant::metadata::TimelineMetadata;
-use crate::tenant::storage_layer::LayerName;
+use crate::tenant::storage_layer::LayerFileName;
 use crate::tenant::upload_queue::UploadQueueInitialized;
 use crate::tenant::Generation;
 use pageserver_api::shard::ShardIndex;
@@ -76,7 +76,7 @@ pub struct IndexPart {
    ///
    /// Older versions of `IndexPart` will not have this property or have only a part of metadata
    /// that latest version stores.
-    pub layer_metadata: HashMap<LayerName, IndexLayerMetadata>,
+    pub layer_metadata: HashMap<LayerFileName, IndexLayerMetadata>,

    // 'disk_consistent_lsn' is a copy of the 'disk_consistent_lsn' in the metadata.
    // It's duplicated for convenience when reading the serialized structure, but is
@@ -85,9 +85,6 @@ pub struct IndexPart {

    #[serde(rename = "metadata_bytes")]
    pub metadata: TimelineMetadata,
-
-    #[serde(default)]
-    pub(crate) lineage: Lineage,
 }

 impl IndexPart {
@@ -100,23 +97,22 @@ impl IndexPart {
    /// - 3: no longer deserialize `timeline_layers` (serialized format is the same, but timeline_layers
    ///      is always generated from the keys of `layer_metadata`)
    /// - 4: timeline_layers is fully removed.
-    /// - 5: lineage was added
-    const LATEST_VERSION: usize = 5;
+    const LATEST_VERSION: usize = 4;

    // Versions we may see when reading from a bucket.
-    pub const KNOWN_VERSIONS: &'static [usize] = &[1, 2, 3, 4, 5];
+    pub const KNOWN_VERSIONS: &'static [usize] = &[1, 2, 3, 4];

    pub const FILE_NAME: &'static str = "index_part.json";

-    fn new(
-        layers_and_metadata: &HashMap<LayerName, LayerFileMetadata>,
+    pub fn new(
+        layers_and_metadata: HashMap<LayerFileName, LayerFileMetadata>,
        disk_consistent_lsn: Lsn,
        metadata: TimelineMetadata,
-        lineage: Lineage,
    ) -> Self {
+        // Transform LayerFileMetadata into IndexLayerMetadata
        let layer_metadata = layers_and_metadata
-            .iter()
-            .map(|(k, v)| (k.to_owned(), IndexLayerMetadata::from(v)))
+            .into_iter()
+            .map(|(k, v)| (k, IndexLayerMetadata::from(v)))
            .collect();

        Self {
@@ -125,7 +121,6 @@ impl IndexPart {
            disk_consistent_lsn,
            metadata,
            deleted_at: None,
-            lineage,
        }
    }

@@ -146,26 +141,20 @@ impl IndexPart {
    pub fn to_s3_bytes(&self) -> serde_json::Result<Vec<u8>> {
        serde_json::to_vec(self)
    }
-
-    #[cfg(test)]
-    pub(crate) fn example() -> Self {
-        let example_metadata = TimelineMetadata::example();
-        Self::new(
-            &HashMap::new(),
-            example_metadata.disk_consistent_lsn(),
-            example_metadata,
-            Default::default(),
-        )
-    }
 }

-impl From<&UploadQueueInitialized> for IndexPart {
-    fn from(uq: &UploadQueueInitialized) -> Self {
-        let disk_consistent_lsn = uq.latest_metadata.disk_consistent_lsn();
-        let metadata = uq.latest_metadata.clone();
-        let lineage = uq.latest_lineage.clone();
+impl TryFrom<&UploadQueueInitialized> for IndexPart {
+    type Error = SerializeError;

-        Self::new(&uq.latest_files, disk_consistent_lsn, metadata, lineage)
+    fn try_from(upload_queue: &UploadQueueInitialized) -> Result<Self, Self::Error> {
+        let disk_consistent_lsn = upload_queue.latest_metadata.disk_consistent_lsn();
+        let metadata = upload_queue.latest_metadata.clone();
+
+        Ok(Self::new(
+            upload_queue.latest_files.clone(),
+            disk_consistent_lsn,
+            metadata,
+        ))
    }
 }

@@ -183,8 +172,8 @@ pub struct IndexLayerMetadata {
    pub shard: ShardIndex,
 }

-impl From<&LayerFileMetadata> for IndexLayerMetadata {
-    fn from(other: &LayerFileMetadata) -> Self {
+impl From<LayerFileMetadata> for IndexLayerMetadata {
+    fn from(other: LayerFileMetadata) -> Self {
        IndexLayerMetadata {
            file_size: other.file_size,
            generation: other.generation,
@@ -193,76 +182,8 @@ impl From<&LayerFileMetadata> for IndexLayerMetadata {
    }
 }

-/// Limited history of earlier ancestors.
-///
-/// A timeline can have more than 1 earlier ancestor, in the rare case that it was repeatedly
-/// reparented by having an later timeline be detached from it's ancestor.
-#[derive(Debug, PartialEq, Eq, Clone, Serialize, Deserialize, Default)]
-pub(crate) struct Lineage {
-    /// Has the `reparenting_history` been truncated to [`Lineage::REMEMBER_AT_MOST`].
-    #[serde(skip_serializing_if = "is_false", default)]
-    reparenting_history_truncated: bool,
-
-    /// Earlier ancestors, truncated when [`Self::reparenting_history_truncated`]
-    ///
-    /// These are stored in case we want to support WAL based DR on the timeline. There can be many
-    /// of these and at most one [`Self::original_ancestor`]. There cannot be more reparentings
-    /// after [`Self::original_ancestor`] has been set.
-    #[serde(skip_serializing_if = "Vec::is_empty", default)]
-    reparenting_history: Vec<TimelineId>,
-
-    /// The ancestor from which this timeline has been detached from and when.
-    ///
-    /// If you are adding support for detaching from a hierarchy, consider changing the ancestry
-    /// into a `Vec<(TimelineId, Lsn)>` to be a path instead.
-    #[serde(skip_serializing_if = "Option::is_none", default)]
-    original_ancestor: Option<(TimelineId, Lsn, NaiveDateTime)>,
-}
-
-fn is_false(b: &bool) -> bool {
-    !b
-}
-
-impl Lineage {
-    const REMEMBER_AT_MOST: usize = 100;
-
-    pub(crate) fn record_previous_ancestor(&mut self, old_ancestor: &TimelineId) {
-        if self.reparenting_history.last() == Some(old_ancestor) {
-            // do not re-record it
-            return;
-        }
-
-        let drop_oldest = self.reparenting_history.len() + 1 >= Self::REMEMBER_AT_MOST;
-
-        self.reparenting_history_truncated |= drop_oldest;
-        if drop_oldest {
-            self.reparenting_history.remove(0);
-        }
-        self.reparenting_history.push(*old_ancestor);
-    }
-
-    pub(crate) fn record_detaching(&mut self, branchpoint: &(TimelineId, Lsn)) {
-        assert!(self.original_ancestor.is_none());
-
-        self.original_ancestor =
-            Some((branchpoint.0, branchpoint.1, chrono::Utc::now().naive_utc()));
-    }
-
-    /// The queried lsn is most likely the basebackup lsn, and this answers question "is it allowed
-    /// to start a read/write primary at this lsn".
-    ///
-    /// Returns true if the Lsn was previously a branch point.
-    pub(crate) fn is_previous_ancestor_lsn(&self, lsn: Lsn) -> bool {
-        self.original_ancestor
-            .as_ref()
-            .is_some_and(|(_, ancestor_lsn, _)| lsn == *ancestor_lsn)
-    }
-}
-
 #[cfg(test)]
 mod tests {
-    use std::str::FromStr;
-
    use super::*;

    #[test]
@@ -298,7 +219,6 @@ mod tests {
            disk_consistent_lsn: "0/16960E8".parse::<Lsn>().unwrap(),
            metadata: TimelineMetadata::from_bytes(&[113,11,159,210,0,54,0,4,0,0,0,0,1,105,96,232,1,0,0,0,0,1,105,96,112,0,0,0,0,0,0,0,0,0,0,0,0,0,1,105,96,112,0,0,0,0,1,105,96,112,0,0,0,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]).unwrap(),
            deleted_at: None,
-            lineage: Lineage::default(),
        };

        let part = IndexPart::from_s3_bytes(example.as_bytes()).unwrap();
@@ -339,7 +259,6 @@ mod tests {
            disk_consistent_lsn: "0/16960E8".parse::<Lsn>().unwrap(),
            metadata: TimelineMetadata::from_bytes(&[113,11,159,210,0,54,0,4,0,0,0,0,1,105,96,232,1,0,0,0,0,1,105,96,112,0,0,0,0,0,0,0,0,0,0,0,0,0,1,105,96,112,0,0,0,0,1,105,96,112,0,0,0,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]).unwrap(),
            deleted_at: None,
-            lineage: Lineage::default(),
        };

        let part = IndexPart::from_s3_bytes(example.as_bytes()).unwrap();
@@ -381,8 +300,7 @@ mod tests {
            disk_consistent_lsn: "0/16960E8".parse::<Lsn>().unwrap(),
            metadata: TimelineMetadata::from_bytes(&[113,11,159,210,0,54,0,4,0,0,0,0,1,105,96,232,1,0,0,0,0,1,105,96,112,0,0,0,0,0,0,0,0,0,0,0,0,0,1,105,96,112,0,0,0,0,1,105,96,112,0,0,0,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]).unwrap(),
            deleted_at: Some(chrono::NaiveDateTime::parse_from_str(
-                "2023-07-31T09:00:00.123000000", "%Y-%m-%dT%H:%M:%S.%f").unwrap()),
-            lineage: Lineage::default(),
+                "2023-07-31T09:00:00.123000000", "%Y-%m-%dT%H:%M:%S.%f").unwrap())
        };

        let part = IndexPart::from_s3_bytes(example.as_bytes()).unwrap();
@@ -427,7 +345,6 @@ mod tests {
            ])
            .unwrap(),
            deleted_at: None,
-            lineage: Lineage::default(),
        };

        let empty_layers_parsed = IndexPart::from_s3_bytes(empty_layers_json.as_bytes()).unwrap();
@@ -466,58 +383,11 @@ mod tests {
            ]),
            disk_consistent_lsn: "0/16960E8".parse::<Lsn>().unwrap(),
            metadata: TimelineMetadata::from_bytes(&[113,11,159,210,0,54,0,4,0,0,0,0,1,105,96,232,1,0,0,0,0,1,105,96,112,0,0,0,0,0,0,0,0,0,0,0,0,0,1,105,96,112,0,0,0,0,1,105,96,112,0,0,0,14,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]).unwrap(),
-            deleted_at: Some(parse_naive_datetime("2023-07-31T09:00:00.123000000")),
-            lineage: Lineage::default(),
+            deleted_at: Some(chrono::NaiveDateTime::parse_from_str(
+                "2023-07-31T09:00:00.123000000", "%Y-%m-%dT%H:%M:%S.%f").unwrap()),
        };

        let part = IndexPart::from_s3_bytes(example.as_bytes()).unwrap();
        assert_eq!(part, expected);
    }
-
-    #[test]
-    fn v5_indexpart_is_parsed() {
-        let example = r#"{
-            "version":5,
-            "layer_metadata":{
-                "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000014EF420-00000000014EF499":{"file_size":23289856,"generation":1},
-                "000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000014EF499-00000000015A7619":{"file_size":1015808,"generation":1}},
-                "disk_consistent_lsn":"0/15A7618",
-                "metadata_bytes":[226,88,25,241,0,46,0,4,0,0,0,0,1,90,118,24,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,78,244,32,0,0,0,0,1,78,244,32,0,0,0,16,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],
-                "lineage":{
-                    "original_ancestor":["e2bfd8c633d713d279e6fcd2bcc15b6d","0/15A7618","2024-05-07T18:52:36.322426563"],
-                    "reparenting_history":["e1bfd8c633d713d279e6fcd2bcc15b6d"]
-                }
-        }"#;
-
-        let expected = IndexPart {
-            version: 5,
-            layer_metadata: HashMap::from([
-                ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000014EF420-00000000014EF499".parse().unwrap(), IndexLayerMetadata {
-                    file_size: 23289856,
-                    generation: Generation::new(1),
-                    shard: ShardIndex::unsharded(),
-                }),
-                ("000000000000000000000000000000000000-FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF__00000000014EF499-00000000015A7619".parse().unwrap(), IndexLayerMetadata {
-                    file_size: 1015808,
-                    generation: Generation::new(1),
-                    shard: ShardIndex::unsharded(),
-                })
-            ]),
-            disk_consistent_lsn: Lsn::from_str("0/15A7618").unwrap(),
-            metadata: TimelineMetadata::from_bytes(&[226,88,25,241,0,46,0,4,0,0,0,0,1,90,118,24,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,78,244,32,0,0,0,0,1,78,244,32,0,0,0,16,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]).unwrap(),
-            deleted_at: None,
-            lineage: Lineage {
-                reparenting_history_truncated: false,
-                reparenting_history: vec![TimelineId::from_str("e1bfd8c633d713d279e6fcd2bcc15b6d").unwrap()],
-                original_ancestor: Some((TimelineId::from_str("e2bfd8c633d713d279e6fcd2bcc15b6d").unwrap(), Lsn::from_str("0/15A7618").unwrap(), parse_naive_datetime("2024-05-07T18:52:36.322426563"))),
-            },
-        };
-
-        let part = IndexPart::from_s3_bytes(example.as_bytes()).unwrap();
-        assert_eq!(part, expected);
-    }
-
-    fn parse_naive_datetime(s: &str) -> NaiveDateTime {
-        chrono::NaiveDateTime::parse_from_str(s, "%Y-%m-%dT%H:%M:%S.%f").unwrap()
-    }
 }
--- a/pageserver/src/tenant/remote_timeline_client/upload.rs
+++ b/pageserver/src/tenant/remote_timeline_client/upload.rs
@@ -12,13 +12,18 @@ use tokio_util::sync::CancellationToken;
 use utils::backoff;

 use super::Generation;
-use crate::tenant::remote_timeline_client::{
-    index::IndexPart, remote_index_path, remote_initdb_archive_path,
-    remote_initdb_preserved_archive_path,
+use crate::{
+    config::PageServerConf,
+    tenant::remote_timeline_client::{
+        index::IndexPart, remote_index_path, remote_initdb_archive_path,
+        remote_initdb_preserved_archive_path, remote_path,
+    },
 };
-use remote_storage::{GenericRemoteStorage, RemotePath, TimeTravelError};
+use remote_storage::{GenericRemoteStorage, TimeTravelError};
 use utils::id::{TenantId, TimelineId};

+use super::index::LayerFileMetadata;
+
 use tracing::info;

 /// Serializes and uploads the given index part data to the remote storage.
@@ -60,10 +65,11 @@ pub(crate) async fn upload_index_part<'a>(
 ///
 /// On an error, bumps the retries count and reschedules the entire task.
 pub(super) async fn upload_timeline_layer<'a>(
+    conf: &'static PageServerConf,
    storage: &'a GenericRemoteStorage,
-    local_path: &'a Utf8Path,
-    remote_path: &'a RemotePath,
-    metadata_size: u64,
+    source_path: &'a Utf8Path,
+    known_metadata: &'a LayerFileMetadata,
+    generation: Generation,
    cancel: &CancellationToken,
 ) -> anyhow::Result<()> {
    fail_point!("before-upload-layer", |_| {
@@ -72,7 +78,8 @@ pub(super) async fn upload_timeline_layer<'a>(

    pausable_failpoint!("before-upload-layer-pausable");

-    let source_file_res = fs::File::open(&local_path).await;
+    let storage_path = remote_path(conf, source_path, generation)?;
+    let source_file_res = fs::File::open(&source_path).await;
    let source_file = match source_file_res {
        Ok(source_file) => source_file,
        Err(e) if e.kind() == ErrorKind::NotFound => {
@@ -83,49 +90,34 @@ pub(super) async fn upload_timeline_layer<'a>(
            // it has been written to disk yet.
            //
            // This is tested against `test_compaction_delete_before_upload`
-            info!(path = %local_path, "File to upload doesn't exist. Likely the file has been deleted and an upload is not required any more.");
+            info!(path = %source_path, "File to upload doesn't exist. Likely the file has been deleted and an upload is not required any more.");
            return Ok(());
        }
-        Err(e) => Err(e).with_context(|| format!("open a source file for layer {local_path:?}"))?,
+        Err(e) => {
+            Err(e).with_context(|| format!("open a source file for layer {source_path:?}"))?
+        }
    };

    let fs_size = source_file
        .metadata()
        .await
-        .with_context(|| format!("get the source file metadata for layer {local_path:?}"))?
+        .with_context(|| format!("get the source file metadata for layer {source_path:?}"))?
        .len();

+    let metadata_size = known_metadata.file_size();
    if metadata_size != fs_size {
-        bail!("File {local_path:?} has its current FS size {fs_size} diferent from initially determined {metadata_size}");
+        bail!("File {source_path:?} has its current FS size {fs_size} diferent from initially determined {metadata_size}");
    }

    let fs_size = usize::try_from(fs_size)
-        .with_context(|| format!("convert {local_path:?} size {fs_size} usize"))?;
+        .with_context(|| format!("convert {source_path:?} size {fs_size} usize"))?;

    let reader = tokio_util::io::ReaderStream::with_capacity(source_file, super::BUFFER_SIZE);

    storage
-        .upload(reader, fs_size, remote_path, None, cancel)
+        .upload(reader, fs_size, &storage_path, None, cancel)
        .await
-        .with_context(|| format!("upload layer from local path '{local_path}'"))
-}
-
-pub(super) async fn copy_timeline_layer(
-    storage: &GenericRemoteStorage,
-    source_path: &RemotePath,
-    target_path: &RemotePath,
-    cancel: &CancellationToken,
-) -> anyhow::Result<()> {
-    fail_point!("before-copy-layer", |_| {
-        bail!("failpoint before-copy-layer")
-    });
-
-    pausable_failpoint!("before-copy-layer-pausable");
-
-    storage
-        .copy_object(source_path, target_path, cancel)
-        .await
-        .with_context(|| format!("copy layer {source_path} to {target_path}"))
+        .with_context(|| format!("upload layer from local path '{source_path}'"))
 }

 /// Uploads the given `initdb` data to the remote storage.
--- a/pageserver/src/tenant/secondary.rs
+++ b/pageserver/src/tenant/secondary.rs
@@ -7,7 +7,6 @@ use std::{sync::Arc, time::SystemTime};

 use crate::{
    config::PageServerConf,
-    context::RequestContext,
    disk_usage_eviction_task::DiskUsageEvictionInfo,
    task_mgr::{self, TaskKind, BACKGROUND_RUNTIME},
    virtual_file::MaybeFatalIo,
@@ -21,9 +20,8 @@ use self::{
 use super::{
    config::{SecondaryLocationConfig, TenantConfOpt},
    mgr::TenantManager,
-    remote_timeline_client::LayerFileMetadata,
    span::debug_assert_current_span_has_tenant_id,
-    storage_layer::{layer::local_layer_path, LayerName},
+    storage_layer::LayerFileName,
 };

 use pageserver_api::{
@@ -182,8 +180,7 @@ impl SecondaryTenant {
        self: &Arc<Self>,
        conf: &PageServerConf,
        timeline_id: TimelineId,
-        name: LayerName,
-        metadata: LayerFileMetadata,
+        name: LayerFileName,
    ) {
        debug_assert_current_span_has_tenant_id();

@@ -197,13 +194,9 @@ impl SecondaryTenant {

        let now = SystemTime::now();

-        let local_path = local_layer_path(
-            conf,
-            &self.tenant_shard_id,
-            &timeline_id,
-            &name,
-            &metadata.generation,
-        );
+        let path = conf
+            .timeline_path(&self.tenant_shard_id, &timeline_id)
+            .join(name.file_name());

        let this = self.clone();

@@ -214,7 +207,7 @@ impl SecondaryTenant {
            // it, the secondary downloader could have seen an updated heatmap that
            // resulted in a layer being deleted.
            // Other local I/O errors are process-fatal: these should never happen.
-            let deleted = std::fs::remove_file(local_path);
+            let deleted = std::fs::remove_file(path);

            let not_found = deleted
                .as_ref()
@@ -323,13 +316,9 @@ pub fn spawn_tasks(
    let (upload_req_tx, upload_req_rx) =
        tokio::sync::mpsc::channel::<CommandRequest<UploadCommand>>(16);

-    let downloader_task_ctx = RequestContext::new(
-        TaskKind::SecondaryDownloads,
-        crate::context::DownloadBehavior::Download,
-    );
    task_mgr::spawn(
        BACKGROUND_RUNTIME.handle(),
-        downloader_task_ctx.task_kind(),
+        TaskKind::SecondaryDownloads,
        None,
        None,
        "secondary tenant downloads",
@@ -341,7 +330,6 @@ pub fn spawn_tasks(
                download_req_rx,
                bg_jobs_clone,
                cancel_clone,
-                downloader_task_ctx,
            )
            .await;

--- a/pageserver/src/tenant/secondary/downloader.rs
+++ b/pageserver/src/tenant/secondary/downloader.rs
@@ -8,7 +8,6 @@ use std::{

 use crate::{
    config::PageServerConf,
-    context::RequestContext,
    disk_usage_eviction_task::{
        finite_f32, DiskUsageEvictionInfo, EvictionCandidate, EvictionLayer, EvictionSecondaryLayer,
    },
@@ -22,7 +21,7 @@ use crate::{
            FAILED_REMOTE_OP_RETRIES,
        },
        span::debug_assert_current_span_has_tenant_id,
-        storage_layer::{layer::local_layer_path, LayerName},
+        storage_layer::LayerFileName,
        tasks::{warn_when_period_overrun, BackgroundLoopKind},
    },
    virtual_file::{on_fatal_io_error, MaybeFatalIo, VirtualFile},
@@ -31,10 +30,7 @@ use crate::{

 use super::{
    heatmap::HeatMapLayer,
-    scheduler::{
-        self, period_jitter, period_warmup, Completion, JobGenerator, SchedulingResult,
-        TenantBackgroundJobs,
-    },
+    scheduler::{self, Completion, JobGenerator, SchedulingResult, TenantBackgroundJobs},
    SecondaryTenant,
 };

@@ -48,6 +44,7 @@ use chrono::format::{DelayedFormat, StrftimeItems};
 use futures::Future;
 use pageserver_api::models::SecondaryProgress;
 use pageserver_api::shard::TenantShardId;
+use rand::Rng;
 use remote_storage::{DownloadError, Etag, GenericRemoteStorage};

 use tokio_util::sync::CancellationToken;
@@ -77,14 +74,12 @@ pub(super) async fn downloader_task(
    command_queue: tokio::sync::mpsc::Receiver<CommandRequest<DownloadCommand>>,
    background_jobs_can_start: Barrier,
    cancel: CancellationToken,
-    root_ctx: RequestContext,
 ) {
    let concurrency = tenant_manager.get_conf().secondary_download_concurrency;

    let generator = SecondaryDownloader {
        tenant_manager,
        remote_storage,
-        root_ctx,
    };
    let mut scheduler = Scheduler::new(generator, concurrency);

@@ -97,7 +92,6 @@ pub(super) async fn downloader_task(
 struct SecondaryDownloader {
    tenant_manager: Arc<TenantManager>,
    remote_storage: GenericRemoteStorage,
-    root_ctx: RequestContext,
 }

 #[derive(Debug, Clone)]
@@ -111,7 +105,7 @@ impl OnDiskState {
        _conf: &'static PageServerConf,
        _tenant_shard_id: &TenantShardId,
        _imeline_id: &TimelineId,
-        _ame: LayerName,
+        _ame: LayerFileName,
        metadata: LayerFileMetadata,
        access_time: SystemTime,
    ) -> Self {
@@ -124,10 +118,10 @@ impl OnDiskState {

 #[derive(Debug, Clone, Default)]
 pub(super) struct SecondaryDetailTimeline {
-    pub(super) on_disk_layers: HashMap<LayerName, OnDiskState>,
+    pub(super) on_disk_layers: HashMap<LayerFileName, OnDiskState>,

    /// We remember when layers were evicted, to prevent re-downloading them.
-    pub(super) evicted_at: HashMap<LayerName, SystemTime>,
+    pub(super) evicted_at: HashMap<LayerFileName, SystemTime>,
 }

 /// This state is written by the secondary downloader, it is opaque
@@ -276,7 +270,7 @@ impl JobGenerator<PendingDownload, RunningDownload, CompleteDownload, DownloadCo
        // Update freshened_at even if there was an error: we don't want errored tenants to implicitly
        // take priority to run again.
        let mut detail = secondary_state.detail.lock().unwrap();
-        detail.next_download = Some(Instant::now() + period_jitter(DOWNLOAD_FRESHEN_INTERVAL, 5));
+        detail.next_download = Some(Instant::now() + DOWNLOAD_FRESHEN_INTERVAL);
    }

    async fn schedule(&mut self) -> SchedulingResult<PendingDownload> {
@@ -307,9 +301,11 @@ impl JobGenerator<PendingDownload, RunningDownload, CompleteDownload, DownloadCo
                    }

                    if detail.next_download.is_none() {
-                        // Initialize randomly in the range from 0 to our interval: this uniformly spreads the start times.  Subsequent
-                        // rounds will use a smaller jitter to avoid accidentally synchronizing later.
-                        detail.next_download = Some(now.checked_add(period_warmup(DOWNLOAD_FRESHEN_INTERVAL)).expect(
+                        // Initialize with a jitter: this spreads initial downloads on startup
+                        // or mass-attach across our freshen interval.
+                        let jittered_period =
+                            rand::thread_rng().gen_range(Duration::ZERO..DOWNLOAD_FRESHEN_INTERVAL);
+                        detail.next_download = Some(now.checked_add(jittered_period).expect(
                        "Using our constant, which is known to be small compared with clock range",
                    ));
                    }
@@ -371,12 +367,11 @@ impl JobGenerator<PendingDownload, RunningDownload, CompleteDownload, DownloadCo
        let remote_storage = self.remote_storage.clone();
        let conf = self.tenant_manager.get_conf();
        let tenant_shard_id = *secondary_state.get_tenant_shard_id();
-        let download_ctx = self.root_ctx.attached_child();
        (RunningDownload { barrier }, Box::pin(async move {
            let _completion = completion;

            match TenantDownloader::new(conf, &remote_storage, &secondary_state)
-                .download(&download_ctx)
+                .download()
                .await
            {
                Err(UpdateError::NoData) => {
@@ -490,7 +485,7 @@ impl<'a> TenantDownloader<'a> {
        }
    }

-    async fn download(&self, ctx: &RequestContext) -> Result<(), UpdateError> {
+    async fn download(&self) -> Result<(), UpdateError> {
        debug_assert_current_span_has_tenant_id();

        // For the duration of a download, we must hold the SecondaryTenant::gate, to ensure
@@ -565,7 +560,7 @@ impl<'a> TenantDownloader<'a> {
            }

            let timeline_id = timeline.timeline_id;
-            self.download_timeline(timeline, ctx)
+            self.download_timeline(timeline)
                .instrument(tracing::info_span!(
                    "secondary_download_timeline",
                    tenant_id=%tenant_shard_id.tenant_id,
@@ -621,12 +616,12 @@ impl<'a> TenantDownloader<'a> {
                let layers_in_heatmap = heatmap_timeline
                    .layers
                    .iter()
-                    .map(|l| (&l.name, l.metadata.generation))
+                    .map(|l| &l.name)
                    .collect::<HashSet<_>>();
                let layers_on_disk = timeline_state
                    .on_disk_layers
                    .iter()
-                    .map(|l| (l.0, l.1.metadata.generation))
+                    .map(|l| l.0)
                    .collect::<HashSet<_>>();

                let mut layer_count = layers_on_disk.len();
@@ -637,24 +632,16 @@ impl<'a> TenantDownloader<'a> {
                    .sum();

                // Remove on-disk layers that are no longer present in heatmap
-                for (layer_file_name, generation) in layers_on_disk.difference(&layers_in_heatmap) {
+                for layer in layers_on_disk.difference(&layers_in_heatmap) {
                    layer_count -= 1;
                    layer_byte_count -= timeline_state
                        .on_disk_layers
-                        .get(layer_file_name)
+                        .get(layer)
                        .unwrap()
                        .metadata
                        .file_size();

-                    let local_path = local_layer_path(
-                        self.conf,
-                        self.secondary_state.get_tenant_shard_id(),
-                        timeline_id,
-                        layer_file_name,
-                        generation,
-                    );
-
-                    delete_layers.push((*timeline_id, (*layer_file_name).clone(), local_path));
+                    delete_layers.push((*timeline_id, (*layer).clone()));
                }

                progress.bytes_downloaded += layer_byte_count;
@@ -669,7 +656,11 @@ impl<'a> TenantDownloader<'a> {
        }

        // Execute accumulated deletions
-        for (timeline_id, layer_name, local_path) in delete_layers {
+        for (timeline_id, layer_name) in delete_layers {
+            let timeline_path = self
+                .conf
+                .timeline_path(self.secondary_state.get_tenant_shard_id(), &timeline_id);
+            let local_path = timeline_path.join(layer_name.to_string());
            tracing::info!(timeline_id=%timeline_id, "Removing secondary local layer {layer_name} because it's absent in heatmap",);

            tokio::fs::remove_file(&local_path)
@@ -751,13 +742,12 @@ impl<'a> TenantDownloader<'a> {
        .and_then(|x| x)
    }

-    async fn download_timeline(
-        &self,
-        timeline: HeatMapTimeline,
-        ctx: &RequestContext,
-    ) -> Result<(), UpdateError> {
+    async fn download_timeline(&self, timeline: HeatMapTimeline) -> Result<(), UpdateError> {
        debug_assert_current_span_has_tenant_and_timeline_id();
        let tenant_shard_id = self.secondary_state.get_tenant_shard_id();
+        let timeline_path = self
+            .conf
+            .timeline_path(tenant_shard_id, &timeline.timeline_id);

        // Accumulate updates to the state
        let mut touched = Vec::new();
@@ -807,14 +797,10 @@ impl<'a> TenantDownloader<'a> {
                if cfg!(debug_assertions) {
                    // Debug for https://github.com/neondatabase/neon/issues/6966: check that the files we think
                    // are already present on disk are really there.
-                    let local_path = local_layer_path(
-                        self.conf,
-                        tenant_shard_id,
-                        &timeline.timeline_id,
-                        &layer.name,
-                        &layer.metadata.generation,
-                    );
-
+                    let local_path = self
+                        .conf
+                        .timeline_path(tenant_shard_id, &timeline.timeline_id)
+                        .join(layer.name.file_name());
                    match tokio::fs::metadata(&local_path).await {
                        Ok(meta) => {
                            tracing::debug!(
@@ -889,7 +875,6 @@ impl<'a> TenantDownloader<'a> {
                &layer.name,
                &LayerFileMetadata::from(&layer.metadata),
                &self.secondary_state.cancel,
-                ctx,
            )
            .await
            {
@@ -908,13 +893,7 @@ impl<'a> TenantDownloader<'a> {
            };

            if downloaded_bytes != layer.metadata.file_size {
-                let local_path = local_layer_path(
-                    self.conf,
-                    tenant_shard_id,
-                    &timeline.timeline_id,
-                    &layer.name,
-                    &layer.metadata.generation,
-                );
+                let local_path = timeline_path.join(layer.name.to_string());

                tracing::warn!(
                    "Downloaded layer {} with unexpected size {} != {}.  Removing download.",
@@ -997,7 +976,7 @@ async fn init_timeline_state(

    // As we iterate through layers found on disk, we will look up their metadata from this map.
    // Layers not present in metadata will be discarded.
-    let heatmap_metadata: HashMap<&LayerName, &HeatMapLayer> =
+    let heatmap_metadata: HashMap<&LayerFileName, &HeatMapLayer> =
        heatmap.layers.iter().map(|l| (&l.name, l)).collect();

    while let Some(dentry) = dir
@@ -1034,7 +1013,7 @@ async fn init_timeline_state(
            continue;
        }

-        match LayerName::from_str(file_name) {
+        match LayerFileName::from_str(file_name) {
            Ok(name) => {
                let remote_meta = heatmap_metadata.get(&name);
                match remote_meta {
--- a/pageserver/src/tenant/secondary/heatmap.rs
+++ b/pageserver/src/tenant/secondary/heatmap.rs
@@ -1,6 +1,8 @@
 use std::time::SystemTime;

-use crate::tenant::{remote_timeline_client::index::IndexLayerMetadata, storage_layer::LayerName};
+use crate::tenant::{
+    remote_timeline_client::index::IndexLayerMetadata, storage_layer::LayerFileName,
+};

 use serde::{Deserialize, Serialize};
 use serde_with::{serde_as, DisplayFromStr, TimestampSeconds};
@@ -29,7 +31,7 @@ pub(crate) struct HeatMapTimeline {
 #[serde_as]
 #[derive(Serialize, Deserialize)]
 pub(crate) struct HeatMapLayer {
-    pub(super) name: LayerName,
+    pub(super) name: LayerFileName,
    pub(super) metadata: IndexLayerMetadata,

    #[serde_as(as = "TimestampSeconds<i64>")]
@@ -40,7 +42,7 @@ pub(crate) struct HeatMapLayer {

 impl HeatMapLayer {
    pub(crate) fn new(
-        name: LayerName,
+        name: LayerFileName,
        metadata: IndexLayerMetadata,
        access_time: SystemTime,
    ) -> Self {
--- a/pageserver/src/tenant/secondary/heatmap_uploader.rs
+++ b/pageserver/src/tenant/secondary/heatmap_uploader.rs
@@ -20,14 +20,12 @@ use crate::{

 use futures::Future;
 use pageserver_api::shard::TenantShardId;
+use rand::Rng;
 use remote_storage::{GenericRemoteStorage, TimeoutOrCancel};

 use super::{
    heatmap::HeatMapTenant,
-    scheduler::{
-        self, period_jitter, period_warmup, JobGenerator, RunningJob, SchedulingResult,
-        TenantBackgroundJobs,
-    },
+    scheduler::{self, JobGenerator, RunningJob, SchedulingResult, TenantBackgroundJobs},
    CommandRequest, UploadCommand,
 };
 use tokio_util::sync::CancellationToken;
@@ -183,11 +181,15 @@ impl JobGenerator<UploadPending, WriteInProgress, WriteComplete, UploadCommand>
            let state = self
                .tenants
                .entry(*tenant.get_tenant_shard_id())
-                .or_insert_with(|| UploaderTenantState {
-                    tenant: Arc::downgrade(&tenant),
-                    last_upload: None,
-                    next_upload: Some(now.checked_add(period_warmup(period)).unwrap_or(now)),
-                    last_digest: None,
+                .or_insert_with(|| {
+                    let jittered_period = rand::thread_rng().gen_range(Duration::ZERO..period);
+
+                    UploaderTenantState {
+                        tenant: Arc::downgrade(&tenant),
+                        last_upload: None,
+                        next_upload: Some(now.checked_add(jittered_period).unwrap_or(now)),
+                        last_digest: None,
+                    }
                });

            // Decline to do the upload if insufficient time has passed
@@ -272,7 +274,7 @@ impl JobGenerator<UploadPending, WriteInProgress, WriteComplete, UploadCommand>

            let next_upload = tenant
                .get_heatmap_period()
-                .and_then(|period| now.checked_add(period_jitter(period, 5)));
+                .and_then(|period| now.checked_add(period));

            WriteComplete {
                    tenant_shard_id: *tenant.get_tenant_shard_id(),
--- a/pageserver/src/tenant/secondary/scheduler.rs
+++ b/pageserver/src/tenant/secondary/scheduler.rs
@@ -1,5 +1,4 @@
 use futures::Future;
-use rand::Rng;
 use std::{
    collections::HashMap,
    marker::PhantomData,
@@ -20,26 +19,6 @@ use super::{CommandRequest, CommandResponse};
 const MAX_SCHEDULING_INTERVAL: Duration = Duration::from_secs(10);
 const MIN_SCHEDULING_INTERVAL: Duration = Duration::from_secs(1);

-/// Jitter a Duration by an integer percentage.  Returned values are uniform
-/// in the range 100-pct..100+pct (i.e. a 5% jitter is 5% either way: a ~10% range)
-pub(super) fn period_jitter(d: Duration, pct: u32) -> Duration {
-    if d == Duration::ZERO {
-        d
-    } else {
-        rand::thread_rng().gen_range((d * (100 - pct)) / 100..(d * (100 + pct)) / 100)
-    }
-}
-
-/// When a periodic task first starts, it should wait for some time in the range 0..period, so
-/// that starting many such tasks at the same time spreads them across the time range.
-pub(super) fn period_warmup(period: Duration) -> Duration {
-    if period == Duration::ZERO {
-        period
-    } else {
-        rand::thread_rng().gen_range(Duration::ZERO..period)
-    }
-}
-
 /// Scheduling helper for background work across many tenants.
 ///
 /// Systems that need to run background work across many tenants may use this type
--- a/pageserver/src/tenant/size.rs
+++ b/pageserver/src/tenant/size.rs
@@ -118,6 +118,9 @@ pub(super) async fn gather_inputs(
    ctx: &RequestContext,
 ) -> anyhow::Result<ModelInputs> {
    // refresh is needed to update gc related pitr_cutoff and horizon_cutoff
+    //
+    // FIXME: if a single timeline is deleted while refresh gc info is ongoing, we will fail the
+    // whole computation. It does not make sense from the billing perspective.
    tenant
        .refresh_gc_info(cancel, ctx)
        .await
@@ -189,9 +192,7 @@ pub(super) async fn gather_inputs(
        // than a space bound (horizon cutoff).  This means that if someone drops a database and waits for their
        // PITR interval, they will see synthetic size decrease, even if we are still storing data inside
        // horizon_cutoff.
-        let pitr_cutoff = gc_info.cutoffs.pitr;
-        let horizon_cutoff = gc_info.cutoffs.horizon;
-        let mut next_gc_cutoff = pitr_cutoff;
+        let mut next_gc_cutoff = gc_info.pitr_cutoff;

        // If the caller provided a shorter retention period, use that instead of the GC cutoff.
        let retention_param_cutoff = if let Some(max_retention_period) = max_retention_period {
@@ -218,8 +219,6 @@ pub(super) async fn gather_inputs(
            .map(|lsn| (lsn, LsnKind::BranchPoint))
            .collect::<Vec<_>>();

-        drop(gc_info);
-
        // Add branch points we collected earlier, just in case there were any that were
        // not present in retain_lsns. We will remove any duplicates below later.
        if let Some(this_branchpoints) = branchpoints.get(&timeline_id) {
@@ -298,8 +297,8 @@ pub(super) async fn gather_inputs(
            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(),
-            horizon_cutoff,
-            pitr_cutoff,
+            horizon_cutoff: gc_info.horizon_cutoff,
+            pitr_cutoff: gc_info.pitr_cutoff,
            next_gc_cutoff,
            retention_param_cutoff,
        });
--- a/pageserver/src/tenant/storage_layer.rs
+++ b/pageserver/src/tenant/storage_layer.rs
@@ -1,11 +1,11 @@
 //! Common traits and structs for layers

 pub mod delta_layer;
+mod filename;
 pub mod image_layer;
 pub(crate) mod inmemory_layer;
 pub(crate) mod layer;
 mod layer_desc;
-mod layer_name;

 use crate::context::{AccessStatsBehavior, RequestContext};
 use crate::repository::Value;
@@ -34,10 +34,10 @@ use utils::rate_limit::RateLimit;
 use utils::{id::TimelineId, lsn::Lsn};

 pub use delta_layer::{DeltaLayer, DeltaLayerWriter, ValueRef};
+pub use filename::{DeltaFileName, ImageFileName, LayerFileName};
 pub use image_layer::{ImageLayer, ImageLayerWriter};
 pub use inmemory_layer::InMemoryLayer;
 pub use layer_desc::{PersistentLayerDesc, PersistentLayerKey};
-pub use layer_name::{DeltaLayerName, ImageLayerName, LayerName};

 pub(crate) use layer::{EvictionError, Layer, ResidentLayer};

@@ -646,8 +646,8 @@ pub mod tests {

    use super::*;

-    impl From<DeltaLayerName> for PersistentLayerDesc {
-        fn from(value: DeltaLayerName) -> Self {
+    impl From<DeltaFileName> for PersistentLayerDesc {
+        fn from(value: DeltaFileName) -> Self {
            PersistentLayerDesc::new_delta(
                TenantShardId::from([0; 18]),
                TimelineId::from_array([0; 16]),
@@ -658,8 +658,8 @@ pub mod tests {
        }
    }

-    impl From<ImageLayerName> for PersistentLayerDesc {
-        fn from(value: ImageLayerName) -> Self {
+    impl From<ImageFileName> for PersistentLayerDesc {
+        fn from(value: ImageFileName) -> Self {
            PersistentLayerDesc::new_img(
                TenantShardId::from([0; 18]),
                TimelineId::from_array([0; 16]),
@@ -670,11 +670,11 @@ pub mod tests {
        }
    }

-    impl From<LayerName> for PersistentLayerDesc {
-        fn from(value: LayerName) -> Self {
+    impl From<LayerFileName> for PersistentLayerDesc {
+        fn from(value: LayerFileName) -> Self {
            match value {
-                LayerName::Delta(d) => Self::from(d),
-                LayerName::Image(i) => Self::from(i),
+                LayerFileName::Delta(d) => Self::from(d),
+                LayerFileName::Image(i) => Self::from(i),
            }
        }
    }
--- a/pageserver/src/tenant/storage_layer/delta_layer.rs
+++ b/pageserver/src/tenant/storage_layer/delta_layer.rs
@@ -57,7 +57,6 @@ use std::fs::File;
 use std::io::SeekFrom;
 use std::ops::Range;
 use std::os::unix::fs::FileExt;
-use std::str::FromStr;
 use std::sync::Arc;
 use tokio::sync::OnceCell;
 use tracing::*;
@@ -69,8 +68,7 @@ use utils::{
 };

 use super::{
-    AsLayerDesc, LayerAccessStats, LayerName, PersistentLayerDesc, ResidentLayer,
-    ValuesReconstructState,
+    AsLayerDesc, LayerAccessStats, PersistentLayerDesc, ResidentLayer, ValuesReconstructState,
 };

 ///
@@ -311,13 +309,13 @@ impl DeltaLayer {
            .and_then(|res| res)?;

        // not production code
-        let actual_layer_name = LayerName::from_str(path.file_name().unwrap()).unwrap();
-        let expected_layer_name = self.layer_desc().layer_name();
+        let actual_filename = path.file_name().unwrap().to_owned();
+        let expected_filename = self.layer_desc().filename().file_name();

-        if actual_layer_name != expected_layer_name {
+        if actual_filename != expected_filename {
            println!("warning: filename does not match what is expected from in-file summary");
-            println!("actual: {:?}", actual_layer_name.to_string());
-            println!("expected: {:?}", expected_layer_name.to_string());
+            println!("actual: {:?}", actual_filename);
+            println!("expected: {:?}", expected_filename);
        }

        Ok(Arc::new(loaded))
@@ -430,15 +428,9 @@ impl DeltaLayerWriterInner {
    ///
    /// The values must be appended in key, lsn order.
    ///
-    async fn put_value(
-        &mut self,
-        key: Key,
-        lsn: Lsn,
-        val: Value,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
+    async fn put_value(&mut self, key: Key, lsn: Lsn, val: Value) -> anyhow::Result<()> {
        let (_, res) = self
-            .put_value_bytes(key, lsn, Value::ser(&val)?, val.will_init(), ctx)
+            .put_value_bytes(key, lsn, Value::ser(&val)?, val.will_init())
            .await;
        res
    }
@@ -449,10 +441,9 @@ impl DeltaLayerWriterInner {
        lsn: Lsn,
        val: Vec<u8>,
        will_init: bool,
-        ctx: &RequestContext,
    ) -> (Vec<u8>, anyhow::Result<()>) {
        assert!(self.lsn_range.start <= lsn);
-        let (val, res) = self.blob_writer.write_blob(val, ctx).await;
+        let (val, res) = self.blob_writer.write_blob(val).await;
        let off = match res {
            Ok(off) => off,
            Err(e) => return (val, Err(anyhow::anyhow!(e))),
@@ -472,23 +463,18 @@ impl DeltaLayerWriterInner {
    ///
    /// Finish writing the delta layer.
    ///
-    async fn finish(
-        self,
-        key_end: Key,
-        timeline: &Arc<Timeline>,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<ResidentLayer> {
+    async fn finish(self, key_end: Key, timeline: &Arc<Timeline>) -> anyhow::Result<ResidentLayer> {
        let index_start_blk =
            ((self.blob_writer.size() + PAGE_SZ as u64 - 1) / PAGE_SZ as u64) as u32;

-        let mut file = self.blob_writer.into_inner(ctx).await?;
+        let mut file = self.blob_writer.into_inner().await?;

        // Write out the index
        let (index_root_blk, block_buf) = self.tree.finish()?;
        file.seek(SeekFrom::Start(index_start_blk as u64 * PAGE_SZ as u64))
            .await?;
        for buf in block_buf.blocks {
-            let (_buf, res) = file.write_all(buf, ctx).await;
+            let (_buf, res) = file.write_all(buf).await;
            res?;
        }
        assert!(self.lsn_range.start < self.lsn_range.end);
@@ -508,7 +494,7 @@ impl DeltaLayerWriterInner {
        // TODO: could use smallvec here but it's a pain with Slice<T>
        Summary::ser_into(&summary, &mut buf)?;
        file.seek(SeekFrom::Start(0)).await?;
-        let (_buf, res) = file.write_all(buf, ctx).await;
+        let (_buf, res) = file.write_all(buf).await;
        res?;

        let metadata = file
@@ -606,18 +592,8 @@ impl DeltaLayerWriter {
    ///
    /// The values must be appended in key, lsn order.
    ///
-    pub async fn put_value(
-        &mut self,
-        key: Key,
-        lsn: Lsn,
-        val: Value,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
-        self.inner
-            .as_mut()
-            .unwrap()
-            .put_value(key, lsn, val, ctx)
-            .await
+    pub async fn put_value(&mut self, key: Key, lsn: Lsn, val: Value) -> anyhow::Result<()> {
+        self.inner.as_mut().unwrap().put_value(key, lsn, val).await
    }

    pub async fn put_value_bytes(
@@ -626,12 +602,11 @@ impl DeltaLayerWriter {
        lsn: Lsn,
        val: Vec<u8>,
        will_init: bool,
-        ctx: &RequestContext,
    ) -> (Vec<u8>, anyhow::Result<()>) {
        self.inner
            .as_mut()
            .unwrap()
-            .put_value_bytes(key, lsn, val, will_init, ctx)
+            .put_value_bytes(key, lsn, val, will_init)
            .await
    }

@@ -646,11 +621,10 @@ impl DeltaLayerWriter {
        mut self,
        key_end: Key,
        timeline: &Arc<Timeline>,
-        ctx: &RequestContext,
    ) -> anyhow::Result<ResidentLayer> {
        let inner = self.inner.take().unwrap();
        let temp_path = inner.path.clone();
-        let result = inner.finish(key_end, timeline, ctx).await;
+        let result = inner.finish(key_end, timeline).await;
        // The delta layer files can sometimes be really large. Clean them up.
        if result.is_err() {
            tracing::warn!(
@@ -718,7 +692,7 @@ impl DeltaLayer {
        // TODO: could use smallvec here, but it's a pain with Slice<T>
        Summary::ser_into(&new_summary, &mut buf).context("serialize")?;
        file.seek(SeekFrom::Start(0)).await?;
-        let (_buf, res) = file.write_all(buf, ctx).await;
+        let (_buf, res) = file.write_all(buf).await;
        res?;
        Ok(())
    }
@@ -1141,15 +1115,15 @@ impl DeltaLayerInner {
        Ok(all_keys)
    }

-    /// Using the given writer, write out a version which has the earlier Lsns than `until`.
-    ///
-    /// Return the amount of key value records pushed to the writer.
+    /// Using the given writer, write out a truncated version, where LSNs higher than the
+    /// truncate_at are missing.
+    #[cfg(test)]
    pub(super) async fn copy_prefix(
        &self,
        writer: &mut DeltaLayerWriter,
-        until: Lsn,
+        truncate_at: Lsn,
        ctx: &RequestContext,
-    ) -> anyhow::Result<usize> {
+    ) -> anyhow::Result<()> {
        use crate::tenant::vectored_blob_io::{
            BlobMeta, VectoredReadBuilder, VectoredReadExtended,
        };
@@ -1213,8 +1187,6 @@ impl DeltaLayerInner {
        // FIXME: buffering of DeltaLayerWriter
        let mut per_blob_copy = Vec::new();

-        let mut records = 0;
-
        while let Some(item) = stream.try_next().await? {
            tracing::debug!(?item, "popped");
            let offset = item
@@ -1233,7 +1205,7 @@ impl DeltaLayerInner {

            prev = Option::from(item);

-            let actionable = actionable.filter(|x| x.0.lsn < until);
+            let actionable = actionable.filter(|x| x.0.lsn < truncate_at);

            let builder = if let Some((meta, offsets)) = actionable {
                // extend or create a new builder
@@ -1301,7 +1273,7 @@ impl DeltaLayerInner {
                    let will_init = crate::repository::ValueBytes::will_init(data)
                        .inspect_err(|_e| {
                            #[cfg(feature = "testing")]
-                            tracing::error!(data=?utils::Hex(data), err=?_e, %key, %lsn, "failed to parse will_init out of serialized value");
+                            tracing::error!(data=?utils::Hex(data), err=?_e, "failed to parse will_init out of serialized value");
                        })
                        .unwrap_or(false);

@@ -1309,19 +1281,10 @@ impl DeltaLayerInner {
                    per_blob_copy.extend_from_slice(data);

                    let (tmp, res) = writer
-                        .put_value_bytes(
-                            key,
-                            lsn,
-                            std::mem::take(&mut per_blob_copy),
-                            will_init,
-                            ctx,
-                        )
+                        .put_value_bytes(key, lsn, std::mem::take(&mut per_blob_copy), will_init)
                        .await;
                    per_blob_copy = tmp;
-
                    res?;
-
-                    records += 1;
                }

                buffer = Some(res.buf);
@@ -1333,7 +1296,7 @@ impl DeltaLayerInner {
            "with the sentinel above loop should had handled all"
        );

-        Ok(records)
+        Ok(())
    }

    pub(super) async fn dump(&self, ctx: &RequestContext) -> anyhow::Result<()> {
@@ -1406,6 +1369,7 @@ impl DeltaLayerInner {
        Ok(())
    }

+    #[cfg(test)]
    fn stream_index_forwards<'a, R>(
        &'a self,
        reader: &'a DiskBtreeReader<R, DELTA_KEY_SIZE>,
@@ -1796,14 +1760,12 @@ mod test {

        for entry in entries {
            let (_, res) = writer
-                .put_value_bytes(entry.key, entry.lsn, entry.value, false, &ctx)
+                .put_value_bytes(entry.key, entry.lsn, entry.value, false)
                .await;
            res?;
        }

-        let resident = writer
-            .finish(entries_meta.key_range.end, &timeline, &ctx)
-            .await?;
+        let resident = writer.finish(entries_meta.key_range.end, &timeline).await?;

        let inner = resident.as_delta(&ctx).await?;

@@ -1989,7 +1951,7 @@ mod test {
                .await
                .unwrap();

-            let copied_layer = writer.finish(Key::MAX, &branch, ctx).await.unwrap();
+            let copied_layer = writer.finish(Key::MAX, &branch).await.unwrap();

            copied_layer.as_delta(ctx).await.unwrap();

--- a/pageserver/src/tenant/storage_layer/layer_name.rs
+++ b/pageserver/src/tenant/storage_layer/layer_name.rs
@@ -2,42 +2,40 @@
 //! Helper functions for dealing with filenames of the image and delta layer files.
 //!
 use crate::repository::Key;
-use std::borrow::Cow;
 use std::cmp::Ordering;
 use std::fmt;
 use std::ops::Range;
 use std::str::FromStr;

-use regex::Regex;
 use utils::lsn::Lsn;

 use super::PersistentLayerDesc;

 // Note: Timeline::load_layer_map() relies on this sort order
 #[derive(PartialEq, Eq, Clone, Hash)]
-pub struct DeltaLayerName {
+pub struct DeltaFileName {
    pub key_range: Range<Key>,
    pub lsn_range: Range<Lsn>,
 }

-impl std::fmt::Debug for DeltaLayerName {
+impl std::fmt::Debug for DeltaFileName {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        use super::RangeDisplayDebug;

-        f.debug_struct("DeltaLayerName")
+        f.debug_struct("DeltaFileName")
            .field("key_range", &RangeDisplayDebug(&self.key_range))
            .field("lsn_range", &self.lsn_range)
            .finish()
    }
 }

-impl PartialOrd for DeltaLayerName {
+impl PartialOrd for DeltaFileName {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
 }

-impl Ord for DeltaLayerName {
+impl Ord for DeltaFileName {
    fn cmp(&self, other: &Self) -> Ordering {
        let mut cmp = self.key_range.start.cmp(&other.key_range.start);
        if cmp != Ordering::Equal {
@@ -57,14 +55,16 @@ impl Ord for DeltaLayerName {
    }
 }

-/// Represents the region of the LSN-Key space covered by a DeltaLayer
+/// Represents the filename of a DeltaLayer
 ///
 /// ```text
 ///    <key start>-<key end>__<LSN start>-<LSN end>
 /// ```
-impl DeltaLayerName {
-    /// Parse the part of a delta layer's file name that represents the LayerName. Returns None
-    /// if the filename does not match the expected pattern.
+impl DeltaFileName {
+    ///
+    /// Parse a string as a delta file name. Returns None if the filename does not
+    /// match the expected pattern.
+    ///
    pub fn parse_str(fname: &str) -> Option<Self> {
        let mut parts = fname.split("__");
        let mut key_parts = parts.next()?.split('-');
@@ -74,19 +74,10 @@ impl DeltaLayerName {
        let key_end_str = key_parts.next()?;
        let lsn_start_str = lsn_parts.next()?;
        let lsn_end_str = lsn_parts.next()?;
-
        if parts.next().is_some() || key_parts.next().is_some() || key_parts.next().is_some() {
            return None;
        }

-        if key_start_str.len() != 36
-            || key_end_str.len() != 36
-            || lsn_start_str.len() != 16
-            || lsn_end_str.len() != 16
-        {
-            return None;
-        }
-
        let key_start = Key::from_hex(key_start_str).ok()?;
        let key_end = Key::from_hex(key_end_str).ok()?;

@@ -103,14 +94,14 @@ impl DeltaLayerName {
            // or panic?
        }

-        Some(DeltaLayerName {
+        Some(DeltaFileName {
            key_range: key_start..key_end,
            lsn_range: start_lsn..end_lsn,
        })
    }
 }

-impl fmt::Display for DeltaLayerName {
+impl fmt::Display for DeltaFileName {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(
            f,
@@ -124,29 +115,29 @@ impl fmt::Display for DeltaLayerName {
 }

 #[derive(PartialEq, Eq, Clone, Hash)]
-pub struct ImageLayerName {
+pub struct ImageFileName {
    pub key_range: Range<Key>,
    pub lsn: Lsn,
 }

-impl std::fmt::Debug for ImageLayerName {
+impl std::fmt::Debug for ImageFileName {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        use super::RangeDisplayDebug;

-        f.debug_struct("ImageLayerName")
+        f.debug_struct("ImageFileName")
            .field("key_range", &RangeDisplayDebug(&self.key_range))
            .field("lsn", &self.lsn)
            .finish()
    }
 }

-impl PartialOrd for ImageLayerName {
+impl PartialOrd for ImageFileName {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
 }

-impl Ord for ImageLayerName {
+impl Ord for ImageFileName {
    fn cmp(&self, other: &Self) -> Ordering {
        let mut cmp = self.key_range.start.cmp(&other.key_range.start);
        if cmp != Ordering::Equal {
@@ -162,7 +153,7 @@ impl Ord for ImageLayerName {
    }
 }

-impl ImageLayerName {
+impl ImageFileName {
    pub fn lsn_as_range(&self) -> Range<Lsn> {
        // Saves from having to copypaste this all over
        PersistentLayerDesc::image_layer_lsn_range(self.lsn)
@@ -170,14 +161,16 @@ impl ImageLayerName {
 }

 ///
-/// Represents the part of the Key-LSN space covered by an ImageLayer
+/// Represents the filename of an ImageLayer
 ///
 /// ```text
 ///    <key start>-<key end>__<LSN>
 /// ```
-impl ImageLayerName {
-    /// Parse a string as then LayerName part of an image layer file name. Returns None if the
-    /// filename does not match the expected pattern.
+impl ImageFileName {
+    ///
+    /// Parse a string as an image file name. Returns None if the filename does not
+    /// match the expected pattern.
+    ///
    pub fn parse_str(fname: &str) -> Option<Self> {
        let mut parts = fname.split("__");
        let mut key_parts = parts.next()?.split('-');
@@ -189,23 +182,19 @@ impl ImageLayerName {
            return None;
        }

-        if key_start_str.len() != 36 || key_end_str.len() != 36 || lsn_str.len() != 16 {
-            return None;
-        }
-
        let key_start = Key::from_hex(key_start_str).ok()?;
        let key_end = Key::from_hex(key_end_str).ok()?;

        let lsn = Lsn::from_hex(lsn_str).ok()?;

-        Some(ImageLayerName {
+        Some(ImageFileName {
            key_range: key_start..key_end,
            lsn,
        })
    }
 }

-impl fmt::Display for ImageLayerName {
+impl fmt::Display for ImageFileName {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(
            f,
@@ -216,24 +205,21 @@ impl fmt::Display for ImageLayerName {
        )
    }
 }
-
-/// LayerName is the logical identity of a layer within a LayerMap at a moment in time.  The
-/// LayerName is not a unique filename, as the same LayerName may have multiple physical incarnations
-/// over time (e.g. across shard splits or compression). The physical filenames of layers in local
-/// storage and object names in remote storage consist of the LayerName plus some extra qualifiers
-/// that uniquely identify the physical incarnation of a layer (see [crate::tenant::remote_timeline_client::remote_layer_path])
-/// and [`crate::tenant::storage_layer::layer::local_layer_path`])
 #[derive(Debug, PartialEq, Eq, Hash, Clone)]
-pub enum LayerName {
-    Image(ImageLayerName),
-    Delta(DeltaLayerName),
+pub enum LayerFileName {
+    Image(ImageFileName),
+    Delta(DeltaFileName),
 }

-impl LayerName {
+impl LayerFileName {
+    pub fn file_name(&self) -> String {
+        self.to_string()
+    }
+
    /// Determines if this layer file is considered to be in future meaning we will discard these
    /// layers during timeline initialization from the given disk_consistent_lsn.
    pub(crate) fn is_in_future(&self, disk_consistent_lsn: Lsn) -> bool {
-        use LayerName::*;
+        use LayerFileName::*;
        match self {
            Image(file_name) if file_name.lsn > disk_consistent_lsn => true,
            Delta(file_name) if file_name.lsn_range.end > disk_consistent_lsn + 1 => true,
@@ -242,7 +228,7 @@ impl LayerName {
    }

    pub(crate) fn kind(&self) -> &'static str {
-        use LayerName::*;
+        use LayerFileName::*;
        match self {
            Delta(_) => "delta",
            Image(_) => "image",
@@ -250,7 +236,7 @@ impl LayerName {
    }
 }

-impl fmt::Display for LayerName {
+impl fmt::Display for LayerFileName {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            Self::Image(fname) => write!(f, "{fname}"),
@@ -259,36 +245,23 @@ impl fmt::Display for LayerName {
    }
 }

-impl From<ImageLayerName> for LayerName {
-    fn from(fname: ImageLayerName) -> Self {
+impl From<ImageFileName> for LayerFileName {
+    fn from(fname: ImageFileName) -> Self {
        Self::Image(fname)
    }
 }
-impl From<DeltaLayerName> for LayerName {
-    fn from(fname: DeltaLayerName) -> Self {
+impl From<DeltaFileName> for LayerFileName {
+    fn from(fname: DeltaFileName) -> Self {
        Self::Delta(fname)
    }
 }

-impl FromStr for LayerName {
+impl FromStr for LayerFileName {
    type Err = String;

-    /// Conversion from either a physical layer filename, or the string-ization of
-    /// Self. When loading a physical layer filename, we drop any extra information
-    /// not needed to build Self.
    fn from_str(value: &str) -> Result<Self, Self::Err> {
-        let gen_suffix_regex = Regex::new("^(?<base>.+)(?<gen>-v1-[0-9a-f]{8})$").unwrap();
-        let file_name: Cow<str> = match gen_suffix_regex.captures(value) {
-            Some(captures) => captures
-                .name("base")
-                .expect("Non-optional group")
-                .as_str()
-                .into(),
-            None => value.into(),
-        };
-
-        let delta = DeltaLayerName::parse_str(&file_name);
-        let image = ImageLayerName::parse_str(&file_name);
+        let delta = DeltaFileName::parse_str(value);
+        let image = ImageFileName::parse_str(value);
        let ok = match (delta, image) {
            (None, None) => {
                return Err(format!(
@@ -303,7 +276,7 @@ impl FromStr for LayerName {
    }
 }

-impl serde::Serialize for LayerName {
+impl serde::Serialize for LayerFileName {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
@@ -315,19 +288,19 @@ impl serde::Serialize for LayerName {
    }
 }

-impl<'de> serde::Deserialize<'de> for LayerName {
+impl<'de> serde::Deserialize<'de> for LayerFileName {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
-        deserializer.deserialize_string(LayerNameVisitor)
+        deserializer.deserialize_string(LayerFileNameVisitor)
    }
 }

-struct LayerNameVisitor;
+struct LayerFileNameVisitor;

-impl<'de> serde::de::Visitor<'de> for LayerNameVisitor {
-    type Value = LayerName;
+impl<'de> serde::de::Visitor<'de> for LayerFileNameVisitor {
+    type Value = LayerFileName;

    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
        write!(
@@ -342,42 +315,3 @@ impl<'de> serde::de::Visitor<'de> for LayerNameVisitor {
        v.parse().map_err(|e| E::custom(e))
    }
 }
-
-#[cfg(test)]
-mod test {
-    use super::*;
-    #[test]
-    fn image_layer_parse() -> anyhow::Result<()> {
-        let expected = LayerName::Image(ImageLayerName {
-            key_range: Key::from_i128(0)
-                ..Key::from_hex("000000067F00000001000004DF0000000006").unwrap(),
-            lsn: Lsn::from_hex("00000000014FED58").unwrap(),
-        });
-        let parsed = LayerName::from_str("000000000000000000000000000000000000-000000067F00000001000004DF0000000006__00000000014FED58-v1-00000001").map_err(|s| anyhow::anyhow!(s))?;
-        assert_eq!(parsed, expected,);
-
-        // Omitting generation suffix is valid
-        let parsed = LayerName::from_str("000000000000000000000000000000000000-000000067F00000001000004DF0000000006__00000000014FED58").map_err(|s| anyhow::anyhow!(s))?;
-        assert_eq!(parsed, expected,);
-
-        Ok(())
-    }
-
-    #[test]
-    fn delta_layer_parse() -> anyhow::Result<()> {
-        let expected = LayerName::Delta(DeltaLayerName {
-            key_range: Key::from_i128(0)
-                ..Key::from_hex("000000067F00000001000004DF0000000006").unwrap(),
-            lsn_range: Lsn::from_hex("00000000014FED58").unwrap()
-                ..Lsn::from_hex("000000000154C481").unwrap(),
-        });
-        let parsed = LayerName::from_str("000000000000000000000000000000000000-000000067F00000001000004DF0000000006__00000000014FED58-000000000154C481-v1-00000001").map_err(|s| anyhow::anyhow!(s))?;
-        assert_eq!(parsed, expected);
-
-        // Omitting generation suffix is valid
-        let parsed = LayerName::from_str("000000000000000000000000000000000000-000000067F00000001000004DF0000000006__00000000014FED58-000000000154C481").map_err(|s| anyhow::anyhow!(s))?;
-        assert_eq!(parsed, expected);
-
-        Ok(())
-    }
-}
--- a/pageserver/src/tenant/storage_layer/image_layer.rs
+++ b/pageserver/src/tenant/storage_layer/image_layer.rs
@@ -54,7 +54,6 @@ use std::fs::File;
 use std::io::SeekFrom;
 use std::ops::Range;
 use std::os::unix::prelude::FileExt;
-use std::str::FromStr;
 use std::sync::Arc;
 use tokio::sync::OnceCell;
 use tokio_stream::StreamExt;
@@ -66,10 +65,8 @@ use utils::{
    lsn::Lsn,
 };

-use super::layer_name::ImageLayerName;
-use super::{
-    AsLayerDesc, Layer, LayerName, PersistentLayerDesc, ResidentLayer, ValuesReconstructState,
-};
+use super::filename::ImageFileName;
+use super::{AsLayerDesc, Layer, PersistentLayerDesc, ResidentLayer, ValuesReconstructState};

 ///
 /// Header stored in the beginning of the file
@@ -234,7 +231,7 @@ impl ImageLayer {
        conf: &PageServerConf,
        timeline_id: TimelineId,
        tenant_shard_id: TenantShardId,
-        fname: &ImageLayerName,
+        fname: &ImageFileName,
    ) -> Utf8PathBuf {
        let rand_string: String = rand::thread_rng()
            .sample_iter(&Alphanumeric)
@@ -270,13 +267,13 @@ impl ImageLayer {
            .and_then(|res| res)?;

        // not production code
-        let actual_layer_name = LayerName::from_str(path.file_name().unwrap()).unwrap();
-        let expected_layer_name = self.layer_desc().layer_name();
+        let actual_filename = path.file_name().unwrap().to_owned();
+        let expected_filename = self.layer_desc().filename().file_name();

-        if actual_layer_name != expected_layer_name {
+        if actual_filename != expected_filename {
            println!("warning: filename does not match what is expected from in-file summary");
-            println!("actual: {:?}", actual_layer_name.to_string());
-            println!("expected: {:?}", expected_layer_name.to_string());
+            println!("actual: {:?}", actual_filename);
+            println!("expected: {:?}", expected_filename);
        }

        Ok(loaded)
@@ -360,7 +357,7 @@ impl ImageLayer {
        // TODO: could use smallvec here but it's a pain with Slice<T>
        Summary::ser_into(&new_summary, &mut buf).context("serialize")?;
        file.seek(SeekFrom::Start(0)).await?;
-        let (_buf, res) = file.write_all(buf, ctx).await;
+        let (_buf, res) = file.write_all(buf).await;
        res?;
        Ok(())
    }
@@ -638,7 +635,7 @@ impl ImageLayerWriterInner {
            conf,
            timeline_id,
            tenant_shard_id,
-            &ImageLayerName {
+            &ImageFileName {
                key_range: key_range.clone(),
                lsn,
            },
@@ -680,14 +677,9 @@ impl ImageLayerWriterInner {
    ///
    /// The page versions must be appended in blknum order.
    ///
-    async fn put_image(
-        &mut self,
-        key: Key,
-        img: Bytes,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
+    async fn put_image(&mut self, key: Key, img: Bytes) -> anyhow::Result<()> {
        ensure!(self.key_range.contains(&key));
-        let (_img, res) = self.blob_writer.write_blob(img, ctx).await;
+        let (_img, res) = self.blob_writer.write_blob(img).await;
        // TODO: re-use the buffer for `img` further upstack
        let off = res?;

@@ -701,11 +693,7 @@ impl ImageLayerWriterInner {
    ///
    /// Finish writing the image layer.
    ///
-    async fn finish(
-        self,
-        timeline: &Arc<Timeline>,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<ResidentLayer> {
+    async fn finish(self, timeline: &Arc<Timeline>) -> anyhow::Result<ResidentLayer> {
        let index_start_blk =
            ((self.blob_writer.size() + PAGE_SZ as u64 - 1) / PAGE_SZ as u64) as u32;

@@ -716,7 +704,7 @@ impl ImageLayerWriterInner {
            .await?;
        let (index_root_blk, block_buf) = self.tree.finish()?;
        for buf in block_buf.blocks {
-            let (_buf, res) = file.write_all(buf, ctx).await;
+            let (_buf, res) = file.write_all(buf).await;
            res?;
        }

@@ -736,7 +724,7 @@ impl ImageLayerWriterInner {
        // TODO: could use smallvec here but it's a pain with Slice<T>
        Summary::ser_into(&summary, &mut buf)?;
        file.seek(SeekFrom::Start(0)).await?;
-        let (_buf, res) = file.write_all(buf, ctx).await;
+        let (_buf, res) = file.write_all(buf).await;
        res?;

        let metadata = file
@@ -818,13 +806,8 @@ impl ImageLayerWriter {
    ///
    /// The page versions must be appended in blknum order.
    ///
-    pub async fn put_image(
-        &mut self,
-        key: Key,
-        img: Bytes,
-        ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
-        self.inner.as_mut().unwrap().put_image(key, img, ctx).await
+    pub async fn put_image(&mut self, key: Key, img: Bytes) -> anyhow::Result<()> {
+        self.inner.as_mut().unwrap().put_image(key, img).await
    }

    ///
@@ -833,9 +816,8 @@ impl ImageLayerWriter {
    pub(crate) async fn finish(
        mut self,
        timeline: &Arc<Timeline>,
-        ctx: &RequestContext,
    ) -> anyhow::Result<super::ResidentLayer> {
-        self.inner.take().unwrap().finish(timeline, ctx).await
+        self.inner.take().unwrap().finish(timeline).await
    }
 }

--- a/pageserver/src/tenant/storage_layer/inmemory_layer.rs
+++ b/pageserver/src/tenant/storage_layer/inmemory_layer.rs
@@ -659,14 +659,14 @@ impl InMemoryLayer {
                let will_init = Value::des(&buf)?.will_init();
                let res;
                (buf, res) = delta_layer_writer
-                    .put_value_bytes(*key, *lsn, buf, will_init, &ctx)
+                    .put_value_bytes(*key, *lsn, buf, will_init)
                    .await;
                res?;
            }
        }

        // MAX is used here because we identify L0 layers by full key range
-        let delta_layer = delta_layer_writer.finish(Key::MAX, timeline, &ctx).await?;
+        let delta_layer = delta_layer_writer.finish(Key::MAX, timeline).await?;
        Ok(Some(delta_layer))
    }
 }
--- a/pageserver/src/tenant/storage_layer/layer.rs
+++ b/pageserver/src/tenant/storage_layer/layer.rs
@@ -4,28 +4,26 @@ use pageserver_api::keyspace::KeySpace;
 use pageserver_api::models::{
    HistoricLayerInfo, LayerAccessKind, LayerResidenceEventReason, LayerResidenceStatus,
 };
-use pageserver_api::shard::{ShardIndex, TenantShardId};
+use pageserver_api::shard::ShardIndex;
 use std::ops::Range;
 use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};
 use std::sync::{Arc, Weak};
 use std::time::{Duration, SystemTime};
 use tracing::Instrument;
-use utils::id::TimelineId;
 use utils::lsn::Lsn;
 use utils::sync::heavier_once_cell;

 use crate::config::PageServerConf;
-use crate::context::{DownloadBehavior, RequestContext};
+use crate::context::RequestContext;
 use crate::repository::Key;
 use crate::span::debug_assert_current_span_has_tenant_and_timeline_id;
-use crate::task_mgr::TaskKind;
 use crate::tenant::timeline::GetVectoredError;
 use crate::tenant::{remote_timeline_client::LayerFileMetadata, Timeline};

 use super::delta_layer::{self, DeltaEntry};
 use super::image_layer;
 use super::{
-    AsLayerDesc, LayerAccessStats, LayerAccessStatsReset, LayerName, PersistentLayerDesc,
+    AsLayerDesc, LayerAccessStats, LayerAccessStatsReset, LayerFileName, PersistentLayerDesc,
    ValueReconstructResult, ValueReconstructState, ValuesReconstructState,
 };

@@ -124,42 +122,14 @@ impl PartialEq for Layer {
    }
 }

-pub(crate) fn local_layer_path(
-    conf: &PageServerConf,
-    tenant_shard_id: &TenantShardId,
-    timeline_id: &TimelineId,
-    layer_file_name: &LayerName,
-    _generation: &Generation,
-) -> Utf8PathBuf {
-    let timeline_path = conf.timeline_path(tenant_shard_id, timeline_id);
-
-    timeline_path.join(layer_file_name.to_string())
-
-    // TODO: switch to enabling new-style layer paths after next release
-    // if generation.is_none() {
-    //     // Without a generation, we may only use legacy path style
-    //     timeline_path.join(layer_file_name.to_string())
-    // } else {
-    //     timeline_path.join(format!("{}-v1{}", layer_file_name, generation.get_suffix()))
-    // }
-}
-
 impl Layer {
    /// Creates a layer value for a file we know to not be resident.
    pub(crate) fn for_evicted(
        conf: &'static PageServerConf,
        timeline: &Arc<Timeline>,
-        file_name: LayerName,
+        file_name: LayerFileName,
        metadata: LayerFileMetadata,
    ) -> Self {
-        let local_path = local_layer_path(
-            conf,
-            &timeline.tenant_shard_id,
-            &timeline.timeline_id,
-            &file_name,
-            &metadata.generation,
-        );
-
        let desc = PersistentLayerDesc::from_filename(
            timeline.tenant_shard_id,
            timeline.timeline_id,
@@ -172,7 +142,6 @@ impl Layer {
        let owner = Layer(Arc::new(LayerInner::new(
            conf,
            timeline,
-            local_path,
            access_stats,
            desc,
            None,
@@ -189,8 +158,7 @@ impl Layer {
    pub(crate) fn for_resident(
        conf: &'static PageServerConf,
        timeline: &Arc<Timeline>,
-        local_path: Utf8PathBuf,
-        file_name: LayerName,
+        file_name: LayerFileName,
        metadata: LayerFileMetadata,
    ) -> ResidentLayer {
        let desc = PersistentLayerDesc::from_filename(
@@ -215,7 +183,6 @@ impl Layer {
            LayerInner::new(
                conf,
                timeline,
-                local_path,
                access_stats,
                desc,
                Some(inner),
@@ -257,19 +224,9 @@ impl Layer {
                LayerResidenceStatus::Resident,
                LayerResidenceEventReason::LayerCreate,
            );
-
-            let local_path = local_layer_path(
-                conf,
-                &timeline.tenant_shard_id,
-                &timeline.timeline_id,
-                &desc.layer_name(),
-                &timeline.generation,
-            );
-
            LayerInner::new(
                conf,
                timeline,
-                local_path,
                access_stats,
                desc,
                Some(inner),
@@ -452,13 +409,6 @@ impl Layer {
        self.0.metadata()
    }

-    pub(crate) fn get_timeline_id(&self) -> Option<TimelineId> {
-        self.0
-            .timeline
-            .upgrade()
-            .map(|timeline| timeline.timeline_id)
-    }
-
    /// Traditional debug dumping facility
    #[allow(unused)]
    pub(crate) async fn dump(&self, verbose: bool, ctx: &RequestContext) -> anyhow::Result<()> {
@@ -690,7 +640,7 @@ impl Drop for LayerInner {
        let span = tracing::info_span!(parent: None, "layer_delete", tenant_id = %self.layer_desc().tenant_shard_id.tenant_id, shard_id=%self.layer_desc().tenant_shard_id.shard_slug(), timeline_id = %self.layer_desc().timeline_id);

        let path = std::mem::take(&mut self.path);
-        let file_name = self.layer_desc().layer_name();
+        let file_name = self.layer_desc().filename();
        let file_size = self.layer_desc().file_size;
        let timeline = self.timeline.clone();
        let meta = self.metadata();
@@ -758,17 +708,19 @@ impl Drop for LayerInner {
 }

 impl LayerInner {
-    #[allow(clippy::too_many_arguments)]
    fn new(
        conf: &'static PageServerConf,
        timeline: &Arc<Timeline>,
-        local_path: Utf8PathBuf,
        access_stats: LayerAccessStats,
        desc: PersistentLayerDesc,
        downloaded: Option<Arc<DownloadedLayer>>,
        generation: Generation,
        shard: ShardIndex,
    ) -> Self {
+        let path = conf
+            .timeline_path(&timeline.tenant_shard_id, &timeline.timeline_id)
+            .join(desc.filename().to_string());
+
        let (inner, version, init_status) = if let Some(inner) = downloaded {
            let version = inner.version;
            let resident = ResidentOrWantedEvicted::Resident(inner);
@@ -783,10 +735,8 @@ impl LayerInner {

        LayerInner {
            conf,
-            debug_str: {
-                format!("timelines/{}/{}", timeline.timeline_id, desc.layer_name()).into()
-            },
-            path: local_path,
+            debug_str: { format!("timelines/{}/{}", timeline.timeline_id, desc.filename()).into() },
+            path,
            desc,
            timeline: Arc::downgrade(timeline),
            have_remote_client: timeline.remote_client.is_some(),
@@ -989,20 +939,11 @@ impl LayerInner {
            return Err(DownloadError::DownloadRequired);
        }

-        let download_ctx = ctx
-            .map(|ctx| ctx.detached_child(TaskKind::LayerDownload, DownloadBehavior::Download))
-            .unwrap_or(RequestContext::new(
-                TaskKind::LayerDownload,
-                DownloadBehavior::Download,
-            ));
-
        async move {
            tracing::info!(%reason, "downloading on-demand");

            let init_cancelled = scopeguard::guard((), |_| LAYER_IMPL_METRICS.inc_init_cancelled());
-            let res = self
-                .download_init_and_wait(timeline, permit, download_ctx)
-                .await?;
+            let res = self.download_init_and_wait(timeline, permit).await?;
            scopeguard::ScopeGuard::into_inner(init_cancelled);
            Ok(res)
        }
@@ -1041,7 +982,6 @@ impl LayerInner {
        self: &Arc<Self>,
        timeline: Arc<Timeline>,
        permit: heavier_once_cell::InitPermit,
-        ctx: RequestContext,
    ) -> Result<Arc<DownloadedLayer>, DownloadError> {
        debug_assert_current_span_has_tenant_and_timeline_id();

@@ -1071,7 +1011,7 @@ impl LayerInner {
                    .await
                    .unwrap();

-                let res = this.download_and_init(timeline, permit, &ctx).await;
+                let res = this.download_and_init(timeline, permit).await;

                if let Err(res) = tx.send(res) {
                    match res {
@@ -1114,7 +1054,6 @@ impl LayerInner {
        self: &Arc<LayerInner>,
        timeline: Arc<Timeline>,
        permit: heavier_once_cell::InitPermit,
-        ctx: &RequestContext,
    ) -> anyhow::Result<Arc<DownloadedLayer>> {
        let client = timeline
            .remote_client
@@ -1122,12 +1061,7 @@ impl LayerInner {
            .expect("checked before download_init_and_wait");

        let result = client
-            .download_layer_file(
-                &self.desc.layer_name(),
-                &self.metadata(),
-                &timeline.cancel,
-                ctx,
-            )
+            .download_layer_file(&self.desc.filename(), &self.metadata(), &timeline.cancel)
            .await;

        match result {
@@ -1260,7 +1194,7 @@ impl LayerInner {
    }

    fn info(&self, reset: LayerAccessStatsReset) -> HistoricLayerInfo {
-        let layer_name = self.desc.layer_name().to_string();
+        let layer_file_name = self.desc.filename().file_name();

        let resident = self
            .inner
@@ -1274,7 +1208,7 @@ impl LayerInner {
            let lsn_range = &self.desc.lsn_range;

            HistoricLayerInfo::Delta {
-                layer_file_name: layer_name,
+                layer_file_name,
                layer_file_size: self.desc.file_size,
                lsn_start: lsn_range.start,
                lsn_end: lsn_range.end,
@@ -1285,7 +1219,7 @@ impl LayerInner {
            let lsn = self.desc.image_layer_lsn();

            HistoricLayerInfo::Image {
-                layer_file_name: layer_name,
+                layer_file_name,
                layer_file_size: self.desc.file_size,
                lsn_start: lsn,
                remote: !resident,
@@ -1846,23 +1780,25 @@ impl ResidentLayer {
        }
    }

-    /// Returns the amount of keys and values written to the writer.
-    pub(crate) async fn copy_delta_prefix(
+    /// FIXME: truncate is bad name because we are not truncating anything, but copying the
+    /// filtered parts.
+    #[cfg(test)]
+    pub(super) async fn copy_delta_prefix(
        &self,
        writer: &mut super::delta_layer::DeltaLayerWriter,
-        until: Lsn,
+        truncate_at: Lsn,
        ctx: &RequestContext,
-    ) -> anyhow::Result<usize> {
+    ) -> anyhow::Result<()> {
        use LayerKind::*;

        let owner = &self.owner.0;

        match self.downloaded.get(owner, ctx).await? {
            Delta(ref d) => d
-                .copy_prefix(writer, until, ctx)
+                .copy_prefix(writer, truncate_at, ctx)
                .await
-                .with_context(|| format!("copy_delta_prefix until {until} of {self}")),
-            Image(_) => anyhow::bail!(format!("cannot copy_lsn_prefix of image layer {self}")),
+                .with_context(|| format!("truncate {self}")),
+            Image(_) => anyhow::bail!(format!("cannot truncate image layer {self}")),
        }
    }

--- a/pageserver/src/tenant/storage_layer/layer_desc.rs
+++ b/pageserver/src/tenant/storage_layer/layer_desc.rs
@@ -5,7 +5,7 @@ use utils::{id::TimelineId, lsn::Lsn};

 use crate::repository::Key;

-use super::{DeltaLayerName, ImageLayerName, LayerName};
+use super::{DeltaFileName, ImageFileName, LayerFileName};

 use serde::{Deserialize, Serialize};

@@ -51,7 +51,7 @@ impl PersistentLayerDesc {
    }

    pub fn short_id(&self) -> impl Display {
-        self.layer_name()
+        self.filename()
    }

    #[cfg(test)]
@@ -103,14 +103,14 @@ impl PersistentLayerDesc {
    pub fn from_filename(
        tenant_shard_id: TenantShardId,
        timeline_id: TimelineId,
-        filename: LayerName,
+        filename: LayerFileName,
        file_size: u64,
    ) -> Self {
        match filename {
-            LayerName::Image(i) => {
+            LayerFileName::Image(i) => {
                Self::new_img(tenant_shard_id, timeline_id, i.key_range, i.lsn, file_size)
            }
-            LayerName::Delta(d) => Self::new_delta(
+            LayerFileName::Delta(d) => Self::new_delta(
                tenant_shard_id,
                timeline_id,
                d.key_range,
@@ -132,34 +132,34 @@ impl PersistentLayerDesc {
        lsn..(lsn + 1)
    }

-    /// Get a delta layer name for this layer.
+    /// Get a delta file name for this layer.
    ///
    /// Panic: if this is not a delta layer.
-    pub fn delta_layer_name(&self) -> DeltaLayerName {
+    pub fn delta_file_name(&self) -> DeltaFileName {
        assert!(self.is_delta);
-        DeltaLayerName {
+        DeltaFileName {
            key_range: self.key_range.clone(),
            lsn_range: self.lsn_range.clone(),
        }
    }

-    /// Get a image layer name for this layer.
+    /// Get a delta file name for this layer.
    ///
    /// Panic: if this is not an image layer, or the lsn range is invalid
-    pub fn image_layer_name(&self) -> ImageLayerName {
+    pub fn image_file_name(&self) -> ImageFileName {
        assert!(!self.is_delta);
        assert!(self.lsn_range.start + 1 == self.lsn_range.end);
-        ImageLayerName {
+        ImageFileName {
            key_range: self.key_range.clone(),
            lsn: self.lsn_range.start,
        }
    }

-    pub fn layer_name(&self) -> LayerName {
+    pub fn filename(&self) -> LayerFileName {
        if self.is_delta {
-            self.delta_layer_name().into()
+            self.delta_file_name().into()
        } else {
-            self.image_layer_name().into()
+            self.image_file_name().into()
        }
    }

--- a/pageserver/src/tenant/tasks.rs
+++ b/pageserver/src/tenant/tasks.rs
@@ -2,7 +2,6 @@
 //! such as compaction and GC

 use std::ops::ControlFlow;
-use std::str::FromStr;
 use std::sync::Arc;
 use std::time::{Duration, Instant};

@@ -10,11 +9,9 @@ use crate::context::{DownloadBehavior, RequestContext};
 use crate::metrics::TENANT_TASK_EVENTS;
 use crate::task_mgr;
 use crate::task_mgr::{TaskKind, BACKGROUND_RUNTIME};
-use crate::tenant::config::defaults::DEFAULT_COMPACTION_PERIOD;
 use crate::tenant::throttle::Stats;
 use crate::tenant::timeline::CompactionError;
 use crate::tenant::{Tenant, TenantState};
-use rand::Rng;
 use tokio_util::sync::CancellationToken;
 use tracing::*;
 use utils::{backoff, completion};
@@ -47,7 +44,6 @@ pub(crate) enum BackgroundLoopKind {
    Compaction,
    Gc,
    Eviction,
-    IngestHouseKeeping,
    ConsumptionMetricsCollectMetrics,
    ConsumptionMetricsSyntheticSizeWorker,
    InitialLogicalSizeCalculation,
@@ -136,30 +132,6 @@ pub fn start_background_loops(
            }
        },
    );
-
-    task_mgr::spawn(
-        BACKGROUND_RUNTIME.handle(),
-        TaskKind::IngestHousekeeping,
-        Some(tenant_shard_id),
-        None,
-        &format!("ingest housekeeping for tenant {tenant_shard_id}"),
-        false,
-        {
-            let tenant = Arc::clone(tenant);
-            let background_jobs_can_start = background_jobs_can_start.cloned();
-            async move {
-                let cancel = task_mgr::shutdown_token();
-                tokio::select! {
-                    _ = cancel.cancelled() => { return Ok(()) },
-                    _ = completion::Barrier::maybe_wait(background_jobs_can_start) => {}
-                };
-                ingest_housekeeping_loop(tenant, cancel)
-                    .instrument(info_span!("ingest_housekeeping_loop", tenant_id = %tenant_shard_id.tenant_id, shard_id = %tenant_shard_id.shard_slug()))
-                    .await;
-                Ok(())
-            }
-        },
-    );
 }

 ///
@@ -407,61 +379,6 @@ async fn gc_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
    TENANT_TASK_EVENTS.with_label_values(&["stop"]).inc();
 }

-async fn ingest_housekeeping_loop(tenant: Arc<Tenant>, cancel: CancellationToken) {
-    TENANT_TASK_EVENTS.with_label_values(&["start"]).inc();
-    async {
-        loop {
-            tokio::select! {
-                _ = cancel.cancelled() => {
-                    return;
-                },
-                tenant_wait_result = wait_for_active_tenant(&tenant) => match tenant_wait_result {
-                    ControlFlow::Break(()) => return,
-                    ControlFlow::Continue(()) => (),
-                },
-            }
-
-            // We run ingest housekeeping with the same frequency as compaction: it is not worth
-            // having a distinct setting.  But we don't run it in the same task, because compaction
-            // blocks on acquiring the background job semaphore.
-            let period = tenant.get_compaction_period();
-
-            // If compaction period is set to zero (to disable it), then we will use a reasonable default
-            let period = if period == Duration::ZERO {
-                humantime::Duration::from_str(DEFAULT_COMPACTION_PERIOD)
-                    .unwrap()
-                    .into()
-            } else {
-                period
-            };
-
-            // Jitter the period by +/- 5%
-            let period =
-                rand::thread_rng().gen_range((period * (95)) / 100..(period * (105)) / 100);
-
-            // Always sleep first: we do not need to do ingest housekeeping early in the lifetime of
-            // a tenant, since it won't have started writing any ephemeral files yet.
-            if tokio::time::timeout(period, cancel.cancelled())
-                .await
-                .is_ok()
-            {
-                break;
-            }
-
-            let started_at = Instant::now();
-            tenant.ingest_housekeeping().await;
-
-            warn_when_period_overrun(
-                started_at.elapsed(),
-                period,
-                BackgroundLoopKind::IngestHouseKeeping,
-            );
-        }
-    }
-    .await;
-    TENANT_TASK_EVENTS.with_label_values(&["stop"]).inc();
-}
-
 async fn wait_for_active_tenant(tenant: &Arc<Tenant>) -> ControlFlow<()> {
    // if the tenant has a proper status already, no need to wait for anything
    if tenant.current_state() == TenantState::Active {
@@ -503,6 +420,8 @@ pub(crate) async fn random_init_delay(
    period: Duration,
    cancel: &CancellationToken,
 ) -> Result<(), Cancelled> {
+    use rand::Rng;
+
    if period == Duration::ZERO {
        return Ok(());
    }
--- a/pageserver/src/tenant/timeline.rs
+++ b/pageserver/src/tenant/timeline.rs
@@ -1,6 +1,5 @@
 mod compaction;
 pub mod delete;
-pub(crate) mod detach_ancestor;
 mod eviction_task;
 mod init;
 pub mod layer_manager;
@@ -17,15 +16,11 @@ use enumset::EnumSet;
 use fail::fail_point;
 use once_cell::sync::Lazy;
 use pageserver_api::{
-    key::{
-        AUX_FILES_KEY, METADATA_KEY_BEGIN_PREFIX, METADATA_KEY_END_PREFIX, NON_INHERITED_RANGE,
-        NON_INHERITED_SPARSE_RANGE,
-    },
+    key::{AUX_FILES_KEY, NON_INHERITED_RANGE},
    keyspace::{KeySpaceAccum, SparseKeyPartitioning},
    models::{
-        AuxFilePolicy, CompactionAlgorithm, DownloadRemoteLayersTaskInfo,
-        DownloadRemoteLayersTaskSpawnRequest, EvictionPolicy, InMemoryLayerInfo, LayerMapInfo,
-        TimelineState,
+        CompactionAlgorithm, DownloadRemoteLayersTaskInfo, DownloadRemoteLayersTaskSpawnRequest,
+        EvictionPolicy, InMemoryLayerInfo, LayerMapInfo, TimelineState,
    },
    reltag::BlockNumber,
    shard::{ShardIdentity, ShardNumber, TenantShardId},
@@ -60,7 +55,7 @@ use std::{
    ops::ControlFlow,
 };

-use crate::tenant::timeline::init::LocalLayerFileMetadata;
+use crate::tenant::timeline::logical_size::CurrentLogicalSize;
 use crate::tenant::{
    layer_map::{LayerMap, SearchResult},
    metadata::TimelineMetadata,
@@ -75,16 +70,13 @@ use crate::{
    disk_usage_eviction_task::finite_f32,
    tenant::storage_layer::{
        AsLayerDesc, DeltaLayerWriter, EvictionError, ImageLayerWriter, InMemoryLayer, Layer,
-        LayerAccessStatsReset, LayerName, ResidentLayer, ValueReconstructResult,
+        LayerAccessStatsReset, LayerFileName, ResidentLayer, ValueReconstructResult,
        ValueReconstructState, ValuesReconstructState,
    },
 };
 use crate::{
    disk_usage_eviction_task::EvictionCandidate, tenant::storage_layer::delta_layer::DeltaEntry,
 };
-use crate::{
-    metrics::ScanLatencyOngoingRecording, tenant::timeline::logical_size::CurrentLogicalSize,
-};
 use crate::{pgdatadir_mapping::LsnForTimestamp, tenant::tasks::BackgroundLoopKind};
 use crate::{
    pgdatadir_mapping::{AuxFilesDirectory, DirectoryKind},
@@ -333,7 +325,7 @@ pub struct Timeline {

    // List of child timelines and their branch points. This is needed to avoid
    // garbage collecting data that is still needed by the child timelines.
-    pub(crate) gc_info: std::sync::RwLock<GcInfo>,
+    pub gc_info: std::sync::RwLock<GcInfo>,

    // It may change across major versions so for simplicity
    // keep it after running initdb for a timeline.
@@ -417,59 +409,33 @@ pub struct WalReceiverInfo {
    pub last_received_msg_ts: u128,
 }

+///
 /// Information about how much history needs to be retained, needed by
 /// Garbage Collection.
-#[derive(Default)]
-pub(crate) struct GcInfo {
+///
+pub struct GcInfo {
    /// Specific LSNs that are needed.
    ///
    /// Currently, this includes all points where child branches have
    /// been forked off from. In the future, could also include
    /// explicit user-defined snapshot points.
-    pub(crate) retain_lsns: Vec<Lsn>,
+    pub retain_lsns: Vec<Lsn>,

-    /// The cutoff coordinates, which are combined by selecting the minimum.
-    pub(crate) cutoffs: GcCutoffs,
-}
-
-impl GcInfo {
-    pub(crate) fn min_cutoff(&self) -> Lsn {
-        self.cutoffs.select_min()
-    }
-}
-
-/// The `GcInfo` component describing which Lsns need to be retained.
-#[derive(Debug)]
-pub(crate) struct GcCutoffs {
-    /// Keep everything newer than this point.
+    /// In addition to 'retain_lsns', keep everything newer than this
+    /// point.
    ///
    /// This is calculated by subtracting 'gc_horizon' setting from
    /// last-record LSN
    ///
    /// FIXME: is this inclusive or exclusive?
-    pub(crate) horizon: Lsn,
+    pub horizon_cutoff: Lsn,

    /// In addition to 'retain_lsns' and 'horizon_cutoff', keep everything newer than this
    /// point.
    ///
    /// This is calculated by finding a number such that a record is needed for PITR
    /// if only if its LSN is larger than 'pitr_cutoff'.
-    pub(crate) pitr: Lsn,
-}
-
-impl Default for GcCutoffs {
-    fn default() -> Self {
-        Self {
-            horizon: Lsn::INVALID,
-            pitr: Lsn::INVALID,
-        }
-    }
-}
-
-impl GcCutoffs {
-    fn select_min(&self) -> Lsn {
-        std::cmp::min(self.horizon, self.pitr)
-    }
+    pub pitr_cutoff: Lsn,
 }

 /// An error happened in a get() operation.
@@ -498,6 +464,7 @@ pub(crate) enum PageReconstructError {

 #[derive(Debug)]
 pub struct MissingKeyError {
+    stuck_at_lsn: bool,
    key: Key,
    shard: ShardNumber,
    cont_lsn: Lsn,
@@ -509,13 +476,23 @@ pub struct MissingKeyError {

 impl std::fmt::Display for MissingKeyError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(
-            f,
-            "could not find data for key {} (shard {:?}) at LSN {}, request LSN {}",
-            self.key, self.shard, self.cont_lsn, self.request_lsn
-        )?;
-        if let Some(ref ancestor_lsn) = self.ancestor_lsn {
-            write!(f, ", ancestor {}", ancestor_lsn)?;
+        if self.stuck_at_lsn {
+            // Records are found in this timeline but no image layer or initial delta record was found.
+            write!(
+                f,
+                "could not find layer with more data for key {} (shard {:?}) at LSN {}, request LSN {}",
+                self.key, self.shard, self.cont_lsn, self.request_lsn
+            )?;
+            if let Some(ref ancestor_lsn) = self.ancestor_lsn {
+                write!(f, ", ancestor {}", ancestor_lsn)?;
+            }
+        } else {
+            // No records in this timeline.
+            write!(
+                f,
+                "could not find data for key {} (shard {:?}) at LSN {}, for request at LSN {}",
+                self.key, self.shard, self.cont_lsn, self.request_lsn
+            )?;
        }

        if !self.traversal_path.is_empty() {
@@ -591,8 +568,8 @@ pub(crate) enum GetVectoredError {
    #[error("Requested at invalid LSN: {0}")]
    InvalidLsn(Lsn),

-    #[error("Requested key not found: {0}")]
-    MissingKey(MissingKeyError),
+    #[error("Requested key {0} not found")]
+    MissingKey(Key),

    #[error(transparent)]
    GetReadyAncestorError(GetReadyAncestorError),
@@ -701,7 +678,7 @@ impl From<GetVectoredError> for PageReconstructError {
            GetVectoredError::Cancelled => PageReconstructError::Cancelled,
            GetVectoredError::InvalidLsn(_) => PageReconstructError::Other(anyhow!("Invalid LSN")),
            err @ GetVectoredError::Oversized(_) => PageReconstructError::Other(err.into()),
-            GetVectoredError::MissingKey(err) => PageReconstructError::MissingKey(err),
+            err @ GetVectoredError::MissingKey(_) => PageReconstructError::Other(err.into()),
            GetVectoredError::GetReadyAncestorError(err) => PageReconstructError::from(err),
            GetVectoredError::Other(err) => PageReconstructError::Other(err),
        }
@@ -865,13 +842,9 @@ impl Timeline {
                // Initialise the reconstruct state for the key with the cache
                // entry returned above.
                let mut reconstruct_state = ValuesReconstructState::new();
-
-                // Only add the cached image to the reconstruct state when it exists.
-                if cached_page_img.is_some() {
-                    let mut key_state = VectoredValueReconstructState::default();
-                    key_state.img = cached_page_img;
-                    reconstruct_state.keys.insert(key, Ok(key_state));
-                }
+                let mut key_state = VectoredValueReconstructState::default();
+                key_state.img = cached_page_img;
+                reconstruct_state.keys.insert(key, Ok(key_state));

                let vectored_res = self
                    .get_vectored_impl(keyspace.clone(), lsn, reconstruct_state, ctx)
@@ -897,15 +870,16 @@ impl Timeline {
                            value
                        }
                    }
-                    None => Err(PageReconstructError::MissingKey(MissingKeyError {
-                        key,
-                        shard: self.shard_identity.get_shard_number(&key),
-                        cont_lsn: Lsn(0),
-                        request_lsn: lsn,
-                        ancestor_lsn: None,
-                        traversal_path: Vec::new(),
-                        backtrace: None,
-                    })),
+                    None => {
+                        error!(
+                            "Expected {}, but singular vectored get returned nothing",
+                            key
+                        );
+                        Err(PageReconstructError::Other(anyhow!(
+                            "Singular vectored get did not return a value for {}",
+                            key
+                        )))
+                    }
                }
            }
        }
@@ -1055,70 +1029,6 @@ impl Timeline {
        res
    }

-    /// Scan the keyspace and return all existing key-values in the keyspace. This currently uses vectored
-    /// get underlying. Normal vectored get would throw an error when a key in the keyspace is not found
-    /// during the search, but for the scan interface, it returns all existing key-value pairs, and does
-    /// not expect each single key in the key space will be found. The semantics is closer to the RocksDB
-    /// scan iterator interface. We could optimize this interface later to avoid some checks in the vectored
-    /// get path to maintain and split the probing and to-be-probe keyspace. We also need to ensure that
-    /// the scan operation will not cause OOM in the future.
-    #[allow(dead_code)]
-    pub(crate) async fn scan(
-        &self,
-        keyspace: KeySpace,
-        lsn: Lsn,
-        ctx: &RequestContext,
-    ) -> Result<BTreeMap<Key, Result<Bytes, PageReconstructError>>, GetVectoredError> {
-        if !lsn.is_valid() {
-            return Err(GetVectoredError::InvalidLsn(lsn));
-        }
-
-        trace!(
-            "key-value scan request for {:?}@{} from task kind {:?}",
-            keyspace,
-            lsn,
-            ctx.task_kind()
-        );
-
-        // We should generalize this into Keyspace::contains in the future.
-        for range in &keyspace.ranges {
-            if range.start.field1 < METADATA_KEY_BEGIN_PREFIX
-                || range.end.field1 > METADATA_KEY_END_PREFIX
-            {
-                return Err(GetVectoredError::Other(anyhow::anyhow!(
-                    "only metadata keyspace can be scanned"
-                )));
-            }
-        }
-
-        let start = crate::metrics::SCAN_LATENCY
-            .for_task_kind(ctx.task_kind())
-            .map(ScanLatencyOngoingRecording::start_recording);
-
-        // start counting after throttle so that throttle time
-        // is always less than observation time
-        let throttled = self
-            .timeline_get_throttle
-            // assume scan = 1 quota for now until we find a better way to process this
-            .throttle(ctx, 1)
-            .await;
-
-        let vectored_res = self
-            .get_vectored_impl(
-                keyspace.clone(),
-                lsn,
-                ValuesReconstructState::default(),
-                ctx,
-            )
-            .await;
-
-        if let Some(recording) = start {
-            recording.observe(throttled);
-        }
-
-        vectored_res
-    }
-
    /// Not subject to [`Self::timeline_get_throttle`].
    pub(super) async fn get_vectored_sequential_impl(
        &self,
@@ -1127,7 +1037,6 @@ impl Timeline {
        ctx: &RequestContext,
    ) -> Result<BTreeMap<Key, Result<Bytes, PageReconstructError>>, GetVectoredError> {
        let mut values = BTreeMap::new();
-
        for range in keyspace.ranges {
            let mut key = range.start;
            while key != range.end {
@@ -1140,17 +1049,16 @@ impl Timeline {
                    Err(Cancelled | AncestorStopping(_)) => {
                        return Err(GetVectoredError::Cancelled)
                    }
-                    Err(MissingKey(_))
-                        if NON_INHERITED_RANGE.contains(&key)
-                            || NON_INHERITED_SPARSE_RANGE.contains(&key) =>
-                    {
-                        // Ignore missing key error for aux key range. TODO: currently, we assume non_inherited_range == aux_key_range.
-                        // When we add more types of keys into the page server, we should revisit this part of code and throw errors
-                        // accordingly.
-                        key = key.next();
-                    }
-                    Err(MissingKey(err)) => {
-                        return Err(GetVectoredError::MissingKey(err));
+                    // we only capture stuck_at_lsn=false now until we figure out https://github.com/neondatabase/neon/issues/7380
+                    Err(MissingKey(MissingKeyError {
+                        stuck_at_lsn: false,
+                        ..
+                    })) if !NON_INHERITED_RANGE.contains(&key) => {
+                        // The vectored read path handles non inherited keys specially.
+                        // If such a a key cannot be reconstructed from the current timeline,
+                        // the vectored read path returns a key level error as opposed to a top
+                        // level error.
+                        return Err(GetVectoredError::MissingKey(key));
                    }
                    Err(Other(err))
                        if err
@@ -1220,17 +1128,11 @@ impl Timeline {
        }
        reconstruct_timer.stop_and_record();

-        // For aux file keys (v1 or v2) the vectored read path does not return an error
-        // when they're missing. Instead they are omitted from the resulting btree
-        // (this is a requirement, not a bug). Skip updating the metric in these cases
-        // to avoid infinite results.
-        if !results.is_empty() {
-            // Note that this is an approximation. Tracking the exact number of layers visited
-            // per key requires virtually unbounded memory usage and is inefficient
-            // (i.e. segment tree tracking each range queried from a layer)
-            crate::metrics::VEC_READ_NUM_LAYERS_VISITED
-                .observe(layers_visited as f64 / results.len() as f64);
-        }
+        // Note that this is an approximation. Tracking the exact number of layers visited
+        // per key requires virtually unbounded memory usage and is inefficient
+        // (i.e. segment tree tracking each range queried from a layer)
+        crate::metrics::VEC_READ_NUM_LAYERS_VISITED
+            .observe(layers_visited as f64 / results.len() as f64);

        Ok(results)
    }
@@ -1243,11 +1145,6 @@ impl Timeline {
        lsn: Lsn,
        ctx: &RequestContext,
    ) {
-        if keyspace.overlaps(&Key::metadata_key_range()) {
-            // skip validation for metadata key range
-            return;
-        }
-
        let sequential_res = self
            .get_vectored_sequential_impl(keyspace.clone(), lsn, ctx)
            .await;
@@ -1257,7 +1154,7 @@ impl Timeline {
            match (lhs, rhs) {
                (Oversized(l), Oversized(r)) => l == r,
                (InvalidLsn(l), InvalidLsn(r)) => l == r,
-                (MissingKey(l), MissingKey(r)) => l.key == r.key,
+                (MissingKey(l), MissingKey(r)) => l == r,
                (GetReadyAncestorError(_), GetReadyAncestorError(_)) => true,
                (Other(_), Other(_)) => true,
                _ => false,
@@ -1272,7 +1169,7 @@ impl Timeline {
                               " - keyspace={:?} lsn={}"),
                       seq_err, keyspace, lsn) },
            (Ok(_), Err(GetVectoredError::GetReadyAncestorError(GetReadyAncestorError::AncestorLsnTimeout(_)))) => {
-                // Sequential get runs after vectored get, so it is possible for the later
+                // Sequential get runs after vectored get, so it is possible for the later 
                // to time out while waiting for its ancestor's Lsn to become ready and for the
                // former to succeed (it essentially has a doubled wait time).
            },
@@ -1507,21 +1404,15 @@ impl Timeline {
    /// Flush to disk all data that was written with the put_* functions
    #[instrument(skip(self), fields(tenant_id=%self.tenant_shard_id.tenant_id, shard_id=%self.tenant_shard_id.shard_slug(), timeline_id=%self.timeline_id))]
    pub(crate) async fn freeze_and_flush(&self) -> anyhow::Result<()> {
-        self.freeze_and_flush0().await
-    }
-
-    // This exists to provide a non-span creating version of `freeze_and_flush` we can call without
-    // polluting the span hierarchy.
-    pub(crate) async fn freeze_and_flush0(&self) -> anyhow::Result<()> {
        let to_lsn = self.freeze_inmem_layer(false).await;
        self.flush_frozen_layers_and_wait(to_lsn).await
    }

-    // Check if an open ephemeral layer should be closed: this provides
-    // background enforcement of checkpoint interval if there is no active WAL receiver, to avoid keeping
-    // an ephemeral layer open forever when idle.  It also freezes layers if the global limit on
-    // ephemeral layer bytes has been breached.
-    pub(super) async fn maybe_freeze_ephemeral_layer(&self) {
+    /// If there is no writer, and conditions for rolling the latest layer are met, then freeze it.
+    ///
+    /// This is for use in background housekeeping, to provide guarantees of layers closing eventually
+    /// even if there are no ongoing writes to drive that.
+    async fn maybe_freeze_ephemeral_layer(&self) {
        let Ok(_write_guard) = self.write_lock.try_lock() else {
            // If the write lock is held, there is an active wal receiver: rolling open layers
            // is their responsibility while they hold this lock.
@@ -1548,11 +1439,13 @@ impl Timeline {
                // we are a sharded tenant and have skipped some WAL
                let last_freeze_ts = *self.last_freeze_ts.read().unwrap();
                if last_freeze_ts.elapsed() >= self.get_checkpoint_timeout() {
-                    // Only do this if have been layer-less longer than get_checkpoint_timeout, so that a shard
-                    // without any data ingested (yet) doesn't write a remote index as soon as it
+                    // This should be somewhat rare, so we log it at INFO level.
+                    //
+                    // We checked for checkpoint timeout so that a shard without any
+                    // data ingested (yet) doesn't write a remote index as soon as it
                    // sees its LSN advance: we only do this if we've been layer-less
                    // for some time.
-                    tracing::debug!(
+                    tracing::info!(
                        "Advancing disk_consistent_lsn past WAL ingest gap {} -> {}",
                        disk_consistent_lsn,
                        last_record_lsn
@@ -1642,6 +1535,11 @@ impl Timeline {
            (guard, permit)
        };

+        // Prior to compaction, check if an open ephemeral layer should be closed: this provides
+        // background enforcement of checkpoint interval if there is no active WAL receiver, to avoid keeping
+        // an ephemeral layer open forever when idle.
+        self.maybe_freeze_ephemeral_layer().await;
+
        // this wait probably never needs any "long time spent" logging, because we already nag if
        // compaction task goes over it's period (20s) which is quite often in production.
        let (_guard, _permit) = tokio::select! {
@@ -1911,7 +1809,7 @@ impl Timeline {
    #[instrument(skip_all, fields(tenant_id = %self.tenant_shard_id.tenant_id, shard_id = %self.tenant_shard_id.shard_slug(), timeline_id = %self.timeline_id))]
    pub(crate) async fn download_layer(
        &self,
-        layer_file_name: &LayerName,
+        layer_file_name: &str,
    ) -> anyhow::Result<Option<bool>> {
        let Some(layer) = self.find_layer(layer_file_name).await else {
            return Ok(None);
@@ -1929,10 +1827,7 @@ impl Timeline {
    /// Evict just one layer.
    ///
    /// Returns `Ok(None)` in the case where the layer could not be found by its `layer_file_name`.
-    pub(crate) async fn evict_layer(
-        &self,
-        layer_file_name: &LayerName,
-    ) -> anyhow::Result<Option<bool>> {
+    pub(crate) async fn evict_layer(&self, layer_file_name: &str) -> anyhow::Result<Option<bool>> {
        let _gate = self
            .gate
            .enter()
@@ -2006,12 +1901,13 @@ const REPARTITION_FREQ_IN_CHECKPOINT_DISTANCE: u64 = 10;

 // Private functions
 impl Timeline {
-    pub(crate) fn get_switch_aux_file_policy(&self) -> AuxFilePolicy {
+    #[allow(dead_code)]
+    pub(crate) fn get_switch_to_aux_file_v2(&self) -> bool {
        let tenant_conf = self.tenant_conf.load();
        tenant_conf
            .tenant_conf
-            .switch_aux_file_policy
-            .unwrap_or(self.conf.default_tenant_conf.switch_aux_file_policy)
+            .switch_to_aux_file_v2
+            .unwrap_or(self.conf.default_tenant_conf.switch_to_aux_file_v2)
    }

    pub(crate) fn get_lazy_slru_download(&self) -> bool {
@@ -2215,7 +2111,11 @@ impl Timeline {

                write_lock: tokio::sync::Mutex::new(None),

-                gc_info: std::sync::RwLock::new(GcInfo::default()),
+                gc_info: std::sync::RwLock::new(GcInfo {
+                    retain_lsns: Vec::new(),
+                    horizon_cutoff: Lsn(0),
+                    pitr_cutoff: Lsn(0),
+                }),

                latest_gc_cutoff_lsn: Rcu::new(metadata.latest_gc_cutoff_lsn()),
                initdb_lsn: metadata.initdb_lsn(),
@@ -2393,13 +2293,13 @@ impl Timeline {
        index_part: Option<IndexPart>,
    ) -> anyhow::Result<()> {
        use init::{Decision::*, Discovered, DismissedLayer};
-        use LayerName::*;
+        use LayerFileName::*;

        let mut guard = self.layers.write().await;

        let timer = self.metrics.load_layer_map_histo.start_timer();

-        // Scan timeline directory and create ImageLayerName and DeltaFilename
+        // Scan timeline directory and create ImageFileName and DeltaFilename
        // structs representing all files on disk
        let timeline_path = self
            .conf
@@ -2423,8 +2323,8 @@ impl Timeline {

                for discovered in discovered {
                    let (name, kind) = match discovered {
-                        Discovered::Layer(layer_file_name, local_path, file_size) => {
-                            discovered_layers.push((layer_file_name, local_path, file_size));
+                        Discovered::Layer(file_name, file_size) => {
+                            discovered_layers.push((file_name, file_size));
                            continue;
                        }
                        Discovered::Metadata => {
@@ -2474,30 +2374,31 @@ impl Timeline {
                        Ok(UseRemote { local, remote }) => {
                            // Remote is authoritative, but we may still choose to retain
                            // the local file if the contents appear to match
-                            if local.metadata.file_size() == remote.file_size() {
+                            if local.file_size() == remote.file_size() {
                                // Use the local file, but take the remote metadata so that we pick up
                                // the correct generation.
-                                UseLocal(
-                                    LocalLayerFileMetadata {
-                                        metadata: remote,
-                                        local_path: local.local_path
-                                    }
-                                )
+                                UseLocal(remote)
                            } else {
-                                init::cleanup_local_file_for_remote(&local, &remote)?;
+                                path.push(name.file_name());
+                                init::cleanup_local_file_for_remote(&path, &local, &remote)?;
+                                path.pop();
                                UseRemote { local, remote }
                            }
                        }
                        Ok(decision) => decision,
                        Err(DismissedLayer::Future { local }) => {
-                            if let Some(local) = local {
-                                init::cleanup_future_layer(&local.local_path, &name, disk_consistent_lsn)?;
+                            if local.is_some() {
+                                path.push(name.file_name());
+                                init::cleanup_future_layer(&path, &name, disk_consistent_lsn)?;
+                                path.pop();
                            }
                            needs_cleanup.push(name);
                            continue;
                        }
                        Err(DismissedLayer::LocalOnly(local)) => {
-                            init::cleanup_local_only_file(&name, &local)?;
+                            path.push(name.file_name());
+                            init::cleanup_local_only_file(&path, &name, &local)?;
+                            path.pop();
                            // this file never existed remotely, we will have to do rework
                            continue;
                        }
@@ -2511,9 +2412,9 @@ impl Timeline {
                    tracing::debug!(layer=%name, ?decision, "applied");

                    let layer = match decision {
-                        UseLocal(local) => {
-                            total_physical_size += local.metadata.file_size();
-                            Layer::for_resident(conf, &this, local.local_path, name, local.metadata).drop_eviction_guard()
+                        UseLocal(m) => {
+                            total_physical_size += m.file_size();
+                            Layer::for_resident(conf, &this, name, m).drop_eviction_guard()
                        }
                        Evicted(remote) | UseRemote { remote, .. } => {
                            Layer::for_evicted(conf, &this, name, remote)
@@ -2994,11 +2895,11 @@ impl Timeline {
        }
    }

-    async fn find_layer(&self, layer_name: &LayerName) -> Option<Layer> {
+    async fn find_layer(&self, layer_file_name: &str) -> Option<Layer> {
        let guard = self.layers.read().await;
        for historic_layer in guard.layer_map().iter_historic_layers() {
-            let historic_layer_name = historic_layer.layer_name();
-            if layer_name == &historic_layer_name {
+            let historic_layer_name = historic_layer.filename().file_name();
+            if layer_file_name == historic_layer_name {
                return Some(guard.get_from_desc(&historic_layer));
            }
        }
@@ -3027,8 +2928,8 @@ impl Timeline {
            let last_activity_ts = layer.access_stats().latest_activity_or_now();

            HeatMapLayer::new(
-                layer.layer_desc().layer_name(),
-                (&layer.metadata()).into(),
+                layer.layer_desc().filename(),
+                layer.metadata().into(),
                last_activity_ts,
            )
        });
@@ -3037,18 +2938,6 @@ impl Timeline {

        Some(HeatMapTimeline::new(self.timeline_id, layers))
    }
-
-    /// Returns true if the given lsn is or was an ancestor branchpoint.
-    pub(crate) fn is_ancestor_lsn(&self, lsn: Lsn) -> bool {
-        // upon timeline detach, we set the ancestor_lsn to Lsn::INVALID and the store the original
-        // branchpoint in the value in IndexPart::lineage
-        self.ancestor_lsn == lsn
-            || (self.ancestor_lsn == Lsn::INVALID
-                && self
-                    .remote_client
-                    .as_ref()
-                    .is_some_and(|rtc| rtc.is_previous_ancestor_lsn(lsn)))
-    }
 }

 type TraversalId = Arc<str>;
@@ -3135,6 +3024,7 @@ impl Timeline {
                            // Didn't make any progress in last iteration. Error out to avoid
                            // getting stuck in the loop.
                            return Err(PageReconstructError::MissingKey(MissingKeyError {
+                                stuck_at_lsn: true,
                                key,
                                shard: self.shard_identity.get_shard_number(&key),
                                cont_lsn: Lsn(cont_lsn.0 - 1),
@@ -3149,6 +3039,7 @@ impl Timeline {
                }
                ValueReconstructResult::Missing => {
                    return Err(PageReconstructError::MissingKey(MissingKeyError {
+                        stuck_at_lsn: false,
                        key,
                        shard: self.shard_identity.get_shard_number(&key),
                        cont_lsn,
@@ -3186,7 +3077,7 @@ impl Timeline {
            if let Some(open_layer) = &layers.open_layer {
                let start_lsn = open_layer.get_lsn_range().start;
                if cont_lsn > start_lsn {
-                    //info!("CHECKING for {} at {} on open layer {}", key, cont_lsn, open_layer.layer_name().display());
+                    //info!("CHECKING for {} at {} on open layer {}", key, cont_lsn, open_layer.filename().display());
                    // Get all the data needed to reconstruct the page version from this layer.
                    // But if we have an older cached page image, no need to go past that.
                    let lsn_floor = max(cached_lsn + 1, start_lsn);
@@ -3215,7 +3106,7 @@ impl Timeline {
            for frozen_layer in layers.frozen_layers.iter().rev() {
                let start_lsn = frozen_layer.get_lsn_range().start;
                if cont_lsn > start_lsn {
-                    //info!("CHECKING for {} at {} on frozen layer {}", key, cont_lsn, frozen_layer.layer_name().display());
+                    //info!("CHECKING for {} at {} on frozen layer {}", key, cont_lsn, frozen_layer.filename().display());
                    let lsn_floor = max(cached_lsn + 1, start_lsn);

                    let frozen_layer = frozen_layer.clone();
@@ -3312,12 +3203,37 @@ impl Timeline {
            // Do not descend into the ancestor timeline for aux files.
            // We don't return a blanket [`GetVectoredError::MissingKey`] to avoid
            // stalling compaction.
-            keyspace.remove_overlapping_with(&KeySpace {
-                ranges: vec![NON_INHERITED_RANGE, NON_INHERITED_SPARSE_RANGE],
-            });
+            // TODO(chi): this will need to be updated for aux files v2 storage
+            if keyspace.overlaps(&NON_INHERITED_RANGE) {
+                let removed = keyspace.remove_overlapping_with(&KeySpace {
+                    ranges: vec![NON_INHERITED_RANGE],
+                });
+
+                for range in removed.ranges {
+                    let mut key = range.start;
+                    while key < range.end {
+                        reconstruct_state.on_key_error(
+                            key,
+                            PageReconstructError::MissingKey(MissingKeyError {
+                                stuck_at_lsn: false,
+                                key,
+                                shard: self.shard_identity.get_shard_number(&key),
+                                cont_lsn,
+                                request_lsn,
+                                ancestor_lsn: None,
+                                traversal_path: Vec::default(),
+                                backtrace: if cfg!(test) {
+                                    Some(std::backtrace::Backtrace::force_capture())
+                                } else {
+                                    None
+                                },
+                            }),
+                        );
+                        key = key.next();
+                    }
+                }
+            }

-            // Keyspace is fully retrieved, no ancestor timeline, or metadata scan (where we do not look
-            // into ancestor timelines). TODO: is there any other metadata which we want to inherit?
            if keyspace.total_raw_size() == 0 || timeline.ancestor_timeline.is_none() {
                break;
            }
@@ -3332,17 +3248,7 @@ impl Timeline {
        }

        if keyspace.total_raw_size() != 0 {
-            return Err(GetVectoredError::MissingKey(MissingKeyError {
-                key: keyspace.start().unwrap(), /* better if we can store the full keyspace */
-                shard: self
-                    .shard_identity
-                    .get_shard_number(&keyspace.start().unwrap()),
-                cont_lsn,
-                request_lsn,
-                ancestor_lsn: Some(timeline.ancestor_lsn),
-                traversal_path: vec![],
-                backtrace: None,
-            }));
+            return Err(GetVectoredError::MissingKey(keyspace.start().unwrap()));
        }

        Ok(())
@@ -3542,7 +3448,7 @@ impl Timeline {
        Ok(ancestor)
    }

-    pub(crate) fn get_ancestor_timeline(&self) -> anyhow::Result<Arc<Timeline>> {
+    fn get_ancestor_timeline(&self) -> anyhow::Result<Arc<Timeline>> {
        let ancestor = self.ancestor_timeline.as_ref().with_context(|| {
            format!(
                "Ancestor is missing. Timeline id: {} Ancestor id {:?}",
@@ -4242,7 +4148,7 @@ impl Timeline {

                    // Maybe flush `key_rest_accum`
                    if key_request_accum.raw_size() >= Timeline::MAX_GET_VECTORED_KEYS
-                        || (last_key_in_range && key_request_accum.raw_size() > 0)
+                        || last_key_in_range
                    {
                        let results = self
                            .get_vectored(key_request_accum.consume_keyspace(), lsn, ctx)
@@ -4280,7 +4186,7 @@ impl Timeline {
                            };

                            // Write all the keys we just read into our new image layer.
-                            image_layer_writer.put_image(img_key, img, ctx).await?;
+                            image_layer_writer.put_image(img_key, img).await?;
                            wrote_keys = true;
                        }
                    }
@@ -4291,7 +4197,7 @@ impl Timeline {
                // Normal path: we have written some data into the new image layer for this
                // partition, so flush it to disk.
                start = img_range.end;
-                let image_layer = image_layer_writer.finish(self, ctx).await?;
+                let image_layer = image_layer_writer.finish(self).await?;
                image_layers.push(image_layer);
            } else {
                // Special case: the image layer may be empty if this is a sharded tenant and the
@@ -4358,48 +4264,6 @@ impl Timeline {
            _ = self.cancel.cancelled() => {}
        )
    }
-
-    /// Detach this timeline from its ancestor by copying all of ancestors layers as this
-    /// Timelines layers up to the ancestor_lsn.
-    ///
-    /// Requires a timeline that:
-    /// - has an ancestor to detach from
-    /// - the ancestor does not have an ancestor -- follows from the original RFC limitations, not
-    /// a technical requirement
-    ///
-    /// After the operation has been started, it cannot be canceled. Upon restart it needs to be
-    /// polled again until completion.
-    ///
-    /// During the operation all timelines sharing the data with this timeline will be reparented
-    /// from our ancestor to be branches of this timeline.
-    pub(crate) async fn prepare_to_detach_from_ancestor(
-        self: &Arc<Timeline>,
-        tenant: &crate::tenant::Tenant,
-        options: detach_ancestor::Options,
-        ctx: &RequestContext,
-    ) -> Result<
-        (
-            completion::Completion,
-            detach_ancestor::PreparedTimelineDetach,
-        ),
-        detach_ancestor::Error,
-    > {
-        detach_ancestor::prepare(self, tenant, options, ctx).await
-    }
-
-    /// Completes the ancestor detach. This method is to be called while holding the
-    /// TenantManager's tenant slot, so during this method we cannot be deleted nor can any
-    /// timeline be deleted. After this method returns successfully, tenant must be reloaded.
-    ///
-    /// Pageserver receiving a SIGKILL during this operation is not supported (yet).
-    pub(crate) async fn complete_detaching_timeline_ancestor(
-        self: &Arc<Timeline>,
-        tenant: &crate::tenant::Tenant,
-        prepared: detach_ancestor::PreparedTimelineDetach,
-        ctx: &RequestContext,
-    ) -> Result<Vec<TimelineId>, anyhow::Error> {
-        detach_ancestor::complete(self, tenant, prepared, ctx).await
-    }
 }

 /// Top-level failure to compact.
@@ -4508,24 +4372,6 @@ impl Timeline {
        Ok(())
    }

-    async fn rewrite_layers(
-        self: &Arc<Self>,
-        replace_layers: Vec<(Layer, ResidentLayer)>,
-        drop_layers: Vec<Layer>,
-    ) -> anyhow::Result<()> {
-        let mut guard = self.layers.write().await;
-
-        guard.rewrite_layers(&replace_layers, &drop_layers, &self.metrics);
-
-        let upload_layers: Vec<_> = replace_layers.into_iter().map(|r| r.1).collect();
-
-        if let Some(remote_client) = self.remote_client.as_ref() {
-            remote_client.schedule_compaction_update(&drop_layers, &upload_layers)?;
-        }
-
-        Ok(())
-    }
-
    /// Schedules the uploads of the given image layers
    fn upload_new_image_layers(
        self: &Arc<Self>,
@@ -4544,7 +4390,7 @@ impl Timeline {
        Ok(())
    }

-    /// Find the Lsns above which layer files need to be retained on
+    /// Update information about which layer files need to be retained on
    /// garbage collection. This is separate from actually performing the GC,
    /// and is updated more frequently, so that compaction can remove obsolete
    /// page versions more aggressively.
@@ -4552,6 +4398,17 @@ impl Timeline {
    /// TODO: that's wishful thinking, compaction doesn't actually do that
    /// currently.
    ///
+    /// The caller specifies how much history is needed with the 3 arguments:
+    ///
+    /// retain_lsns: keep a version of each page at these LSNs
+    /// cutoff_horizon: also keep everything newer than this LSN
+    /// pitr: the time duration required to keep data for PITR
+    ///
+    /// The 'retain_lsns' list is currently used to prevent removing files that
+    /// are needed by child timelines. In the future, the user might be able to
+    /// name additional points in time to retain. The caller is responsible for
+    /// collecting that information.
+    ///
    /// The 'cutoff_horizon' point is used to retain recent versions that might still be
    /// needed by read-only nodes. (As of this writing, the caller just passes
    /// the latest LSN subtracted by a constant, and doesn't do anything smart
@@ -4559,22 +4416,29 @@ impl Timeline {
    ///
    /// The 'pitr' duration is used to calculate a 'pitr_cutoff', which can be used to determine
    /// whether a record is needed for PITR.
+    ///
+    /// NOTE: This function holds a short-lived lock to protect the 'gc_info'
+    /// field, so that the three values passed as argument are stored
+    /// atomically. But the caller is responsible for ensuring that no new
+    /// branches are created that would need to be included in 'retain_lsns',
+    /// for example. The caller should hold `Tenant::gc_cs` lock to ensure
+    /// that.
+    ///
    #[instrument(skip_all, fields(timeline_id=%self.timeline_id))]
-    pub(super) async fn find_gc_cutoffs(
+    pub(super) async fn update_gc_info(
        &self,
+        retain_lsns: Vec<Lsn>,
        cutoff_horizon: Lsn,
        pitr: Duration,
        cancel: &CancellationToken,
        ctx: &RequestContext,
-    ) -> anyhow::Result<GcCutoffs> {
+    ) -> anyhow::Result<()> {
        let _timer = self
            .metrics
-            .find_gc_cutoffs_histo
+            .update_gc_info_histo
            .start_timer()
            .record_on_drop();

-        pausable_failpoint!("Timeline::find_gc_cutoffs-pausable");
-
        // First, calculate pitr_cutoff_timestamp and then convert it to LSN.
        //
        // Some unit tests depend on garbage-collection working even when
@@ -4624,10 +4488,14 @@ impl Timeline {
            self.get_last_record_lsn()
        };

-        Ok(GcCutoffs {
-            horizon: cutoff_horizon,
-            pitr: pitr_cutoff,
-        })
+        // Grab the lock and update the values
+        *self.gc_info.write().unwrap() = GcInfo {
+            retain_lsns,
+            horizon_cutoff: cutoff_horizon,
+            pitr_cutoff,
+        };
+
+        Ok(())
    }

    /// Garbage collect layer files on a timeline that are no longer needed.
@@ -4656,8 +4524,8 @@ impl Timeline {
        let (horizon_cutoff, pitr_cutoff, retain_lsns) = {
            let gc_info = self.gc_info.read().unwrap();

-            let horizon_cutoff = min(gc_info.cutoffs.horizon, self.get_disk_consistent_lsn());
-            let pitr_cutoff = gc_info.cutoffs.pitr;
+            let horizon_cutoff = min(gc_info.horizon_cutoff, self.get_disk_consistent_lsn());
+            let pitr_cutoff = gc_info.pitr_cutoff;
            let retain_lsns = gc_info.retain_lsns.clone();
            (horizon_cutoff, pitr_cutoff, retain_lsns)
        };
@@ -4684,8 +4552,6 @@ impl Timeline {
        retain_lsns: Vec<Lsn>,
        new_gc_cutoff: Lsn,
    ) -> anyhow::Result<GcResult> {
-        // FIXME: if there is an ongoing detach_from_ancestor, we should just skip gc
-
        let now = SystemTime::now();
        let mut result: GcResult = GcResult::default();

@@ -4739,7 +4605,7 @@ impl Timeline {
            if l.get_lsn_range().end > horizon_cutoff {
                debug!(
                    "keeping {} because it's newer than horizon_cutoff {}",
-                    l.layer_name(),
+                    l.filename(),
                    horizon_cutoff,
                );
                result.layers_needed_by_cutoff += 1;
@@ -4750,7 +4616,7 @@ impl Timeline {
            if l.get_lsn_range().end > pitr_cutoff {
                debug!(
                    "keeping {} because it's newer than pitr_cutoff {}",
-                    l.layer_name(),
+                    l.filename(),
                    pitr_cutoff,
                );
                result.layers_needed_by_pitr += 1;
@@ -4769,7 +4635,7 @@ impl Timeline {
                if &l.get_lsn_range().start <= retain_lsn {
                    debug!(
                        "keeping {} because it's still might be referenced by child branch forked at {} is_dropped: xx is_incremental: {}",
-                        l.layer_name(),
+                        l.filename(),
                        retain_lsn,
                        l.is_incremental(),
                    );
@@ -4800,7 +4666,7 @@ impl Timeline {
            if !layers
                .image_layer_exists(&l.get_key_range(), &(l.get_lsn_range().end..new_gc_cutoff))
            {
-                debug!("keeping {} because it is the latest layer", l.layer_name());
+                debug!("keeping {} because it is the latest layer", l.filename());
                result.layers_not_updated += 1;
                continue 'outer;
            }
@@ -4808,7 +4674,7 @@ impl Timeline {
            // We didn't find any reason to keep this file, so remove it.
            debug!(
                "garbage collecting {} is_dropped: xx is_incremental: {}",
-                l.layer_name(),
+                l.filename(),
                l.is_incremental(),
            );
            layers_to_remove.push(l);
--- a/pageserver/src/tenant/timeline/compaction.rs
+++ b/pageserver/src/tenant/timeline/compaction.rs
@@ -15,8 +15,7 @@ use anyhow::{anyhow, Context};
 use enumset::EnumSet;
 use fail::fail_point;
 use itertools::Itertools;
-use pageserver_api::keyspace::ShardedRange;
-use pageserver_api::shard::{ShardCount, ShardIdentity, TenantShardId};
+use pageserver_api::shard::{ShardIdentity, TenantShardId};
 use tokio_util::sync::CancellationToken;
 use tracing::{debug, info, info_span, trace, warn, Instrument};
 use utils::id::TimelineId;
@@ -94,7 +93,7 @@ impl Timeline {
        // Define partitioning schema if needed

        // FIXME: the match should only cover repartitioning, not the next steps
-        let partition_count = match self
+        match self
            .repartition(
                self.get_last_record_lsn(),
                self.get_compaction_target_size(),
@@ -147,7 +146,6 @@ impl Timeline {
                assert!(sparse_layers.is_empty());

                self.upload_new_image_layers(dense_layers)?;
-                dense_partitioning.parts.len()
            }
            Err(err) => {
                // no partitioning? This is normal, if the timeline was just created
@@ -159,150 +157,9 @@ impl Timeline {
                if !self.cancel.is_cancelled() {
                    tracing::error!("could not compact, repartitioning keyspace failed: {err:?}");
                }
-                1
            }
        };

-        if self.shard_identity.count >= ShardCount::new(2) {
-            // Limit the number of layer rewrites to the number of partitions: this means its
-            // runtime should be comparable to a full round of image layer creations, rather than
-            // being potentially much longer.
-            let rewrite_max = partition_count;
-
-            self.compact_shard_ancestors(rewrite_max, ctx).await?;
-        }
-
-        Ok(())
-    }
-
-    /// Check for layers that are elegible to be rewritten:
-    /// - Shard splitting: After a shard split, ancestor layers beyond pitr_interval, so that
-    ///   we don't indefinitely retain keys in this shard that aren't needed.
-    /// - For future use: layers beyond pitr_interval that are in formats we would
-    ///   rather not maintain compatibility with indefinitely.
-    ///
-    /// Note: this phase may read and write many gigabytes of data: use rewrite_max to bound
-    /// how much work it will try to do in each compaction pass.
-    async fn compact_shard_ancestors(
-        self: &Arc<Self>,
-        rewrite_max: usize,
-        _ctx: &RequestContext,
-    ) -> anyhow::Result<()> {
-        let mut drop_layers = Vec::new();
-        let layers_to_rewrite: Vec<Layer> = Vec::new();
-
-        // We will use the PITR cutoff as a condition for rewriting layers.
-        let pitr_cutoff = self.gc_info.read().unwrap().cutoffs.pitr;
-
-        let layers = self.layers.read().await;
-        for layer_desc in layers.layer_map().iter_historic_layers() {
-            let layer = layers.get_from_desc(&layer_desc);
-            if layer.metadata().shard.shard_count == self.shard_identity.count {
-                // This layer does not belong to a historic ancestor, no need to re-image it.
-                continue;
-            }
-
-            // This layer was created on an ancestor shard: check if it contains any data for this shard.
-            let sharded_range = ShardedRange::new(layer_desc.get_key_range(), &self.shard_identity);
-            let layer_local_page_count = sharded_range.page_count();
-            let layer_raw_page_count = ShardedRange::raw_size(&layer_desc.get_key_range());
-            if layer_local_page_count == 0 {
-                // This ancestral layer only covers keys that belong to other shards.
-                // We include the full metadata in the log: if we had some critical bug that caused
-                // us to incorrectly drop layers, this would simplify manually debugging + reinstating those layers.
-                info!(%layer, old_metadata=?layer.metadata(),
-                    "dropping layer after shard split, contains no keys for this shard.",
-                );
-
-                if cfg!(debug_assertions) {
-                    // Expensive, exhaustive check of keys in this layer: this guards against ShardedRange's calculations being
-                    // wrong.  If ShardedRange claims the local page count is zero, then no keys in this layer
-                    // should be !is_key_disposable()
-                    let range = layer_desc.get_key_range();
-                    let mut key = range.start;
-                    while key < range.end {
-                        debug_assert!(self.shard_identity.is_key_disposable(&key));
-                        key = key.next();
-                    }
-                }
-
-                drop_layers.push(layer);
-                continue;
-            } else if layer_local_page_count != u32::MAX
-                && layer_local_page_count == layer_raw_page_count
-            {
-                debug!(%layer,
-                    "layer is entirely shard local ({} keys), no need to filter it",
-                    layer_local_page_count
-                );
-                continue;
-            }
-
-            // Don't bother re-writing a layer unless it will at least halve its size
-            if layer_local_page_count != u32::MAX
-                && layer_local_page_count > layer_raw_page_count / 2
-            {
-                debug!(%layer,
-                    "layer is already mostly local ({}/{}), not rewriting",
-                    layer_local_page_count,
-                    layer_raw_page_count
-                );
-            }
-
-            // Don't bother re-writing a layer if it is within the PITR window: it will age-out eventually
-            // without incurring the I/O cost of a rewrite.
-            if layer_desc.get_lsn_range().end >= pitr_cutoff {
-                debug!(%layer, "Skipping rewrite of layer still in PITR window ({} >= {})",
-                    layer_desc.get_lsn_range().end, pitr_cutoff);
-                continue;
-            }
-
-            if layer_desc.is_delta() {
-                // We do not yet implement rewrite of delta layers
-                debug!(%layer, "Skipping rewrite of delta layer");
-                continue;
-            }
-
-            // Only rewrite layers if they would have different remote paths: either they belong to this
-            // shard but an old generation, or they belonged to another shard.  This also implicitly
-            // guarantees that the layer is persistent in remote storage (as only remote persistent
-            // layers are carried across shard splits, any local-only layer would be in the current generation)
-            if layer.metadata().generation == self.generation
-                && layer.metadata().shard.shard_count == self.shard_identity.count
-            {
-                debug!(%layer, "Skipping rewrite, is not from old generation");
-                continue;
-            }
-
-            if layers_to_rewrite.len() >= rewrite_max {
-                tracing::info!(%layer, "Will rewrite layer on a future compaction, already rewrote {}",
-                    layers_to_rewrite.len()
-                );
-                continue;
-            }
-
-            // Fall through: all our conditions for doing a rewrite passed.
-            // TODO: implement rewriting
-            tracing::debug!(%layer, "Would rewrite layer");
-        }
-
-        // Drop the layers read lock: we will acquire it for write in [`Self::rewrite_layers`]
-        drop(layers);
-
-        // TODO: collect layers to rewrite
-        let replace_layers = Vec::new();
-
-        // Update the LayerMap so that readers will use the new layers, and enqueue it for writing to remote storage
-        self.rewrite_layers(replace_layers, drop_layers).await?;
-
-        if let Some(remote_client) = self.remote_client.as_ref() {
-            // We wait for all uploads to complete before finishing this compaction stage.  This is not
-            // necessary for correctness, but it simplifies testing, and avoids proceeding with another
-            // Timeline's compaction while this timeline's uploads may be generating lots of disk I/O
-            // load.
-            remote_client.wait_completion().await?;
-        }
-
        Ok(())
    }

@@ -663,7 +520,7 @@ impl Timeline {
                            writer
                                .take()
                                .unwrap()
-                                .finish(prev_key.unwrap().next(), self, ctx)
+                                .finish(prev_key.unwrap().next(), self)
                                .await?,
                        );
                        writer = None;
@@ -705,11 +562,7 @@ impl Timeline {
                    );
                }

-                writer
-                    .as_mut()
-                    .unwrap()
-                    .put_value(key, lsn, value, ctx)
-                    .await?;
+                writer.as_mut().unwrap().put_value(key, lsn, value).await?;
            } else {
                debug!(
                    "Dropping key {} during compaction (it belongs on shard {:?})",
@@ -725,7 +578,7 @@ impl Timeline {
            prev_key = Some(key);
        }
        if let Some(writer) = writer {
-            new_layers.push(writer.finish(prev_key.unwrap().next(), self, ctx).await?);
+            new_layers.push(writer.finish(prev_key.unwrap().next(), self).await?);
        }

        // Sync layers
@@ -1119,7 +972,7 @@ impl CompactionJobExecutor for TimelineAdaptor {

            let value = val.load(ctx).await?;

-            writer.put_value(key, lsn, value, ctx).await?;
+            writer.put_value(key, lsn, value).await?;

            prev = Some((key, lsn));
        }
@@ -1135,7 +988,7 @@ impl CompactionJobExecutor for TimelineAdaptor {
        });

        let new_delta_layer = writer
-            .finish(prev.unwrap().0.next(), &self.timeline, ctx)
+            .finish(prev.unwrap().0.next(), &self.timeline)
            .await?;

        self.new_deltas.push(new_delta_layer);
@@ -1205,11 +1058,11 @@ impl TimelineAdaptor {
                        }
                    }
                };
-                image_layer_writer.put_image(key, img, ctx).await?;
+                image_layer_writer.put_image(key, img).await?;
                key = key.next();
            }
        }
-        let image_layer = image_layer_writer.finish(&self.timeline, ctx).await?;
+        let image_layer = image_layer_writer.finish(&self.timeline).await?;

        self.new_images.push(image_layer);

--- a/pageserver/src/tenant/timeline/delete.rs
+++ b/pageserver/src/tenant/timeline/delete.rs
@@ -422,10 +422,6 @@ impl DeleteTimelineFlow {
    pub(crate) fn is_finished(&self) -> bool {
        matches!(self, Self::Finished)
    }
-
-    pub(crate) fn is_not_started(&self) -> bool {
-        matches!(self, Self::NotStarted)
-    }
 }

 struct DeletionGuard(OwnedMutexGuard<DeleteTimelineFlow>);
--- a/pageserver/src/tenant/timeline/detach_ancestor.rs
+++ b/pageserver/src/tenant/timeline/detach_ancestor.rs
@@ -1,540 +0,0 @@
-use std::sync::Arc;
-
-use super::{layer_manager::LayerManager, Timeline};
-use crate::{
-    context::{DownloadBehavior, RequestContext},
-    task_mgr::TaskKind,
-    tenant::{
-        storage_layer::{AsLayerDesc as _, DeltaLayerWriter, Layer, ResidentLayer},
-        Tenant,
-    },
-    virtual_file::{MaybeFatalIo, VirtualFile},
-};
-use tokio_util::sync::CancellationToken;
-use tracing::Instrument;
-use utils::{completion, generation::Generation, id::TimelineId, lsn::Lsn};
-
-#[derive(Debug, thiserror::Error)]
-pub(crate) enum Error {
-    #[error("no ancestors")]
-    NoAncestor,
-    #[error("too many ancestors")]
-    TooManyAncestors,
-    #[error("shutting down, please retry later")]
-    ShuttingDown,
-    #[error("flushing failed")]
-    FlushAncestor(#[source] anyhow::Error),
-    #[error("layer download failed")]
-    RewrittenDeltaDownloadFailed(#[source] anyhow::Error),
-    #[error("copying LSN prefix locally failed")]
-    CopyDeltaPrefix(#[source] anyhow::Error),
-    #[error("upload rewritten layer")]
-    UploadRewritten(#[source] anyhow::Error),
-
-    #[error("ancestor is already being detached by: {}", .0)]
-    OtherTimelineDetachOngoing(TimelineId),
-
-    #[error("remote copying layer failed")]
-    CopyFailed(#[source] anyhow::Error),
-
-    #[error("unexpected error")]
-    Unexpected(#[source] anyhow::Error),
-}
-
-pub(crate) struct PreparedTimelineDetach {
-    layers: Vec<Layer>,
-}
-
-/// TODO: this should be part of PageserverConf because we cannot easily modify cplane arguments.
-#[derive(Debug)]
-pub(crate) struct Options {
-    pub(crate) rewrite_concurrency: std::num::NonZeroUsize,
-    pub(crate) copy_concurrency: std::num::NonZeroUsize,
-}
-
-impl Default for Options {
-    fn default() -> Self {
-        Self {
-            rewrite_concurrency: std::num::NonZeroUsize::new(2).unwrap(),
-            copy_concurrency: std::num::NonZeroUsize::new(10).unwrap(),
-        }
-    }
-}
-
-/// See [`Timeline::prepare_to_detach_from_ancestor`]
-pub(super) async fn prepare(
-    detached: &Arc<Timeline>,
-    tenant: &Tenant,
-    options: Options,
-    ctx: &RequestContext,
-) -> Result<(completion::Completion, PreparedTimelineDetach), Error> {
-    use Error::*;
-
-    if detached.remote_client.as_ref().is_none() {
-        unimplemented!("no new code for running without remote storage");
-    }
-
-    let Some((ancestor, ancestor_lsn)) = detached
-        .ancestor_timeline
-        .as_ref()
-        .map(|tl| (tl.clone(), detached.ancestor_lsn))
-    else {
-        return Err(NoAncestor);
-    };
-
-    if !ancestor_lsn.is_valid() {
-        return Err(NoAncestor);
-    }
-
-    if ancestor.ancestor_timeline.is_some() {
-        // non-technical requirement; we could flatten N ancestors just as easily but we chose
-        // not to
-        return Err(TooManyAncestors);
-    }
-
-    // before we acquire the gate, we must mark the ancestor as having a detach operation
-    // ongoing which will block other concurrent detach operations so we don't get to ackward
-    // situations where there would be two branches trying to reparent earlier branches.
-    let (guard, barrier) = completion::channel();
-
-    {
-        let mut guard = tenant.ongoing_timeline_detach.lock().unwrap();
-        if let Some((tl, other)) = guard.as_ref() {
-            if !other.is_ready() {
-                return Err(OtherTimelineDetachOngoing(*tl));
-            }
-        }
-        *guard = Some((detached.timeline_id, barrier));
-    }
-
-    let _gate_entered = detached.gate.enter().map_err(|_| ShuttingDown)?;
-
-    if ancestor_lsn >= ancestor.get_disk_consistent_lsn() {
-        let span =
-            tracing::info_span!("freeze_and_flush", ancestor_timeline_id=%ancestor.timeline_id);
-        async {
-            let started_at = std::time::Instant::now();
-            let freeze_and_flush = ancestor.freeze_and_flush0();
-            let mut freeze_and_flush = std::pin::pin!(freeze_and_flush);
-
-            let res =
-                tokio::time::timeout(std::time::Duration::from_secs(1), &mut freeze_and_flush)
-                    .await;
-
-            let res = match res {
-                Ok(res) => res,
-                Err(_elapsed) => {
-                    tracing::info!("freezing and flushing ancestor is still ongoing");
-                    freeze_and_flush.await
-                }
-            };
-
-            res.map_err(FlushAncestor)?;
-
-            // we do not need to wait for uploads to complete but we do need `struct Layer`,
-            // copying delta prefix is unsupported currently for `InMemoryLayer`.
-            tracing::info!(
-                elapsed_ms = started_at.elapsed().as_millis(),
-                "froze and flushed the ancestor"
-            );
-            Ok(())
-        }
-        .instrument(span)
-        .await?;
-    }
-
-    let end_lsn = ancestor_lsn + 1;
-
-    let (filtered_layers, straddling_branchpoint, rest_of_historic) = {
-        // we do not need to start from our layers, because they can only be layers that come
-        // *after* ancestor_lsn
-        let layers = tokio::select! {
-            guard = ancestor.layers.read() => guard,
-            _ = detached.cancel.cancelled() => {
-                return Err(ShuttingDown);
-            }
-            _ = ancestor.cancel.cancelled() => {
-                return Err(ShuttingDown);
-            }
-        };
-
-        // between retries, these can change if compaction or gc ran in between. this will mean
-        // we have to redo work.
-        partition_work(ancestor_lsn, &layers)
-    };
-
-    // TODO: layers are already sorted by something: use that to determine how much of remote
-    // copies are already done.
-    tracing::info!(filtered=%filtered_layers, to_rewrite = straddling_branchpoint.len(), historic=%rest_of_historic.len(), "collected layers");
-
-    // TODO: copying and lsn prefix copying could be done at the same time with a single fsync after
-    let mut new_layers: Vec<Layer> =
-        Vec::with_capacity(straddling_branchpoint.len() + rest_of_historic.len());
-
-    {
-        tracing::debug!(to_rewrite = %straddling_branchpoint.len(), "copying prefix of delta layers");
-
-        let mut tasks = tokio::task::JoinSet::new();
-
-        let mut wrote_any = false;
-
-        let limiter = Arc::new(tokio::sync::Semaphore::new(
-            options.rewrite_concurrency.get(),
-        ));
-
-        for layer in straddling_branchpoint {
-            let limiter = limiter.clone();
-            let timeline = detached.clone();
-            let ctx = ctx.detached_child(TaskKind::DetachAncestor, DownloadBehavior::Download);
-
-            tasks.spawn(async move {
-                let _permit = limiter.acquire().await;
-                let copied =
-                    upload_rewritten_layer(end_lsn, &layer, &timeline, &timeline.cancel, &ctx)
-                        .await?;
-                Ok(copied)
-            });
-        }
-
-        while let Some(res) = tasks.join_next().await {
-            match res {
-                Ok(Ok(Some(copied))) => {
-                    wrote_any = true;
-                    tracing::info!(layer=%copied, "rewrote and uploaded");
-                    new_layers.push(copied);
-                }
-                Ok(Ok(None)) => {}
-                Ok(Err(e)) => return Err(e),
-                Err(je) => return Err(Unexpected(je.into())),
-            }
-        }
-
-        // FIXME: the fsync should be mandatory, after both rewrites and copies
-        if wrote_any {
-            let timeline_dir = VirtualFile::open(
-                &detached
-                    .conf
-                    .timeline_path(&detached.tenant_shard_id, &detached.timeline_id),
-            )
-            .await
-            .fatal_err("VirtualFile::open for timeline dir fsync");
-            timeline_dir
-                .sync_all()
-                .await
-                .fatal_err("VirtualFile::sync_all timeline dir");
-        }
-    }
-
-    let mut tasks = tokio::task::JoinSet::new();
-    let limiter = Arc::new(tokio::sync::Semaphore::new(options.copy_concurrency.get()));
-
-    for adopted in rest_of_historic {
-        let limiter = limiter.clone();
-        let timeline = detached.clone();
-
-        tasks.spawn(
-            async move {
-                let _permit = limiter.acquire().await;
-                let owned =
-                    remote_copy(&adopted, &timeline, timeline.generation, &timeline.cancel).await?;
-                tracing::info!(layer=%owned, "remote copied");
-                Ok(owned)
-            }
-            .in_current_span(),
-        );
-    }
-
-    while let Some(res) = tasks.join_next().await {
-        match res {
-            Ok(Ok(owned)) => {
-                new_layers.push(owned);
-            }
-            Ok(Err(failed)) => {
-                return Err(failed);
-            }
-            Err(je) => return Err(Unexpected(je.into())),
-        }
-    }
-
-    // TODO: fsync directory again if we hardlinked something
-
-    let prepared = PreparedTimelineDetach { layers: new_layers };
-
-    Ok((guard, prepared))
-}
-
-fn partition_work(
-    ancestor_lsn: Lsn,
-    source_layermap: &LayerManager,
-) -> (usize, Vec<Layer>, Vec<Layer>) {
-    let mut straddling_branchpoint = vec![];
-    let mut rest_of_historic = vec![];
-
-    let mut later_by_lsn = 0;
-
-    for desc in source_layermap.layer_map().iter_historic_layers() {
-        // off by one chances here:
-        // - start is inclusive
-        // - end is exclusive
-        if desc.lsn_range.start > ancestor_lsn {
-            later_by_lsn += 1;
-            continue;
-        }
-
-        let target = if desc.lsn_range.start <= ancestor_lsn
-            && desc.lsn_range.end > ancestor_lsn
-            && desc.is_delta
-        {
-            // TODO: image layer at Lsn optimization
-            &mut straddling_branchpoint
-        } else {
-            &mut rest_of_historic
-        };
-
-        target.push(source_layermap.get_from_desc(&desc));
-    }
-
-    (later_by_lsn, straddling_branchpoint, rest_of_historic)
-}
-
-async fn upload_rewritten_layer(
-    end_lsn: Lsn,
-    layer: &Layer,
-    target: &Arc<Timeline>,
-    cancel: &CancellationToken,
-    ctx: &RequestContext,
-) -> Result<Option<Layer>, Error> {
-    use Error::UploadRewritten;
-    let copied = copy_lsn_prefix(end_lsn, layer, target, ctx).await?;
-
-    let Some(copied) = copied else {
-        return Ok(None);
-    };
-
-    // FIXME: better shuttingdown error
-    target
-        .remote_client
-        .as_ref()
-        .unwrap()
-        .upload_layer_file(&copied, cancel)
-        .await
-        .map_err(UploadRewritten)?;
-
-    Ok(Some(copied.into()))
-}
-
-async fn copy_lsn_prefix(
-    end_lsn: Lsn,
-    layer: &Layer,
-    target_timeline: &Arc<Timeline>,
-    ctx: &RequestContext,
-) -> Result<Option<ResidentLayer>, Error> {
-    use Error::{CopyDeltaPrefix, RewrittenDeltaDownloadFailed};
-
-    tracing::debug!(%layer, %end_lsn, "copying lsn prefix");
-
-    let mut writer = DeltaLayerWriter::new(
-        target_timeline.conf,
-        target_timeline.timeline_id,
-        target_timeline.tenant_shard_id,
-        layer.layer_desc().key_range.start,
-        layer.layer_desc().lsn_range.start..end_lsn,
-    )
-    .await
-    .map_err(CopyDeltaPrefix)?;
-
-    let resident = layer
-        .download_and_keep_resident()
-        .await
-        // likely shutdown
-        .map_err(RewrittenDeltaDownloadFailed)?;
-
-    let records = resident
-        .copy_delta_prefix(&mut writer, end_lsn, ctx)
-        .await
-        .map_err(CopyDeltaPrefix)?;
-
-    drop(resident);
-
-    tracing::debug!(%layer, records, "copied records");
-
-    if records == 0 {
-        drop(writer);
-        // TODO: we might want to store an empty marker in remote storage for this
-        // layer so that we will not needlessly walk `layer` on repeated attempts.
-        Ok(None)
-    } else {
-        // reuse the key instead of adding more holes between layers by using the real
-        // highest key in the layer.
-        let reused_highest_key = layer.layer_desc().key_range.end;
-        let copied = writer
-            .finish(reused_highest_key, target_timeline, ctx)
-            .await
-            .map_err(CopyDeltaPrefix)?;
-
-        tracing::debug!(%layer, %copied, "new layer produced");
-
-        Ok(Some(copied))
-    }
-}
-
-/// Creates a new Layer instance for the adopted layer, and ensures it is found from the remote
-/// storage on successful return without the adopted layer being added to `index_part.json`.
-async fn remote_copy(
-    adopted: &Layer,
-    adoptee: &Arc<Timeline>,
-    generation: Generation,
-    cancel: &CancellationToken,
-) -> Result<Layer, Error> {
-    use Error::CopyFailed;
-
-    // depending if Layer::keep_resident we could hardlink
-
-    let mut metadata = adopted.metadata();
-    debug_assert!(metadata.generation <= generation);
-    metadata.generation = generation;
-
-    let owned = crate::tenant::storage_layer::Layer::for_evicted(
-        adoptee.conf,
-        adoptee,
-        adopted.layer_desc().layer_name(),
-        metadata,
-    );
-
-    // FIXME: better shuttingdown error
-    adoptee
-        .remote_client
-        .as_ref()
-        .unwrap()
-        .copy_timeline_layer(adopted, &owned, cancel)
-        .await
-        .map(move |()| owned)
-        .map_err(CopyFailed)
-}
-
-/// See [`Timeline::complete_detaching_timeline_ancestor`].
-pub(super) async fn complete(
-    detached: &Arc<Timeline>,
-    tenant: &Tenant,
-    prepared: PreparedTimelineDetach,
-    _ctx: &RequestContext,
-) -> Result<Vec<TimelineId>, anyhow::Error> {
-    let rtc = detached
-        .remote_client
-        .as_ref()
-        .expect("has to have a remote timeline client for timeline ancestor detach");
-
-    let PreparedTimelineDetach { layers } = prepared;
-
-    let ancestor = detached
-        .get_ancestor_timeline()
-        .expect("must still have a ancestor");
-    let ancestor_lsn = detached.get_ancestor_lsn();
-
-    // publish the prepared layers before we reparent any of the timelines, so that on restart
-    // reparented timelines find layers. also do the actual detaching.
-    //
-    // if we crash after this operation, we will at least come up having detached a timeline, but
-    // we cannot go back and reparent the timelines which would had been reparented in normal
-    // execution.
-    //
-    // this is not perfect, but it avoids us a retry happening after a compaction or gc on restart
-    // which could give us a completely wrong layer combination.
-    rtc.schedule_adding_existing_layers_to_index_detach_and_wait(
-        &layers,
-        (ancestor.timeline_id, ancestor_lsn),
-    )
-    .await?;
-
-    let mut tasks = tokio::task::JoinSet::new();
-
-    // because we are now keeping the slot in progress, it is unlikely that there will be any
-    // timeline deletions during this time. if we raced one, then we'll just ignore it.
-    tenant
-        .timelines
-        .lock()
-        .unwrap()
-        .values()
-        .filter_map(|tl| {
-            if Arc::ptr_eq(tl, detached) {
-                return None;
-            }
-
-            if !tl.is_active() {
-                return None;
-            }
-
-            let tl_ancestor = tl.ancestor_timeline.as_ref()?;
-            let is_same = Arc::ptr_eq(&ancestor, tl_ancestor);
-            let is_earlier = tl.get_ancestor_lsn() <= ancestor_lsn;
-
-            let is_deleting = tl
-                .delete_progress
-                .try_lock()
-                .map(|flow| !flow.is_not_started())
-                .unwrap_or(true);
-
-            if is_same && is_earlier && !is_deleting {
-                Some(tl.clone())
-            } else {
-                None
-            }
-        })
-        .for_each(|timeline| {
-            // important in this scope: we are holding the Tenant::timelines lock
-            let span = tracing::info_span!("reparent", reparented=%timeline.timeline_id);
-            let new_parent = detached.timeline_id;
-
-            tasks.spawn(
-                async move {
-                    let res = timeline
-                        .remote_client
-                        .as_ref()
-                        .expect("reparented has to have remote client because detached has one")
-                        .schedule_reparenting_and_wait(&new_parent)
-                        .await;
-
-                    match res {
-                        Ok(()) => Some(timeline),
-                        Err(e) => {
-                            // with the use of tenant slot, we no longer expect these.
-                            tracing::warn!("reparenting failed: {e:#}");
-                            None
-                        }
-                    }
-                }
-                .instrument(span),
-            );
-        });
-
-    let reparenting_candidates = tasks.len();
-    let mut reparented = Vec::with_capacity(tasks.len());
-
-    while let Some(res) = tasks.join_next().await {
-        match res {
-            Ok(Some(timeline)) => {
-                tracing::info!(reparented=%timeline.timeline_id, "reparenting done");
-                reparented.push(timeline.timeline_id);
-            }
-            Ok(None) => {
-                // lets just ignore this for now. one or all reparented timelines could had
-                // started deletion, and that is fine.
-            }
-            Err(je) if je.is_cancelled() => unreachable!("not used"),
-            Err(je) if je.is_panic() => {
-                // ignore; it's better to continue with a single reparenting failing (or even
-                // all of them) in order to get to the goal state.
-                //
-                // these timelines will never be reparentable, but they can be always detached as
-                // separate tree roots.
-            }
-            Err(je) => tracing::error!("unexpected join error: {je:?}"),
-        }
-    }
-
-    if reparenting_candidates != reparented.len() {
-        tracing::info!("failed to reparent some candidates");
-    }
-
-    Ok(reparented)
-}
--- a/pageserver/src/tenant/timeline/init.rs
+++ b/pageserver/src/tenant/timeline/init.rs
@@ -6,13 +6,13 @@ use crate::{
            self,
            index::{IndexPart, LayerFileMetadata},
        },
-        storage_layer::LayerName,
+        storage_layer::LayerFileName,
        Generation,
    },
    METADATA_FILE_NAME,
 };
 use anyhow::Context;
-use camino::{Utf8Path, Utf8PathBuf};
+use camino::Utf8Path;
 use pageserver_api::shard::ShardIndex;
 use std::{collections::HashMap, str::FromStr};
 use utils::lsn::Lsn;
@@ -20,7 +20,7 @@ use utils::lsn::Lsn;
 /// Identified files in the timeline directory.
 pub(super) enum Discovered {
    /// The only one we care about
-    Layer(LayerName, Utf8PathBuf, u64),
+    Layer(LayerFileName, u64),
    /// Old ephmeral files from previous launches, should be removed
    Ephemeral(String),
    /// Old temporary timeline files, unsure what these really are, should be removed
@@ -43,10 +43,10 @@ pub(super) fn scan_timeline_dir(path: &Utf8Path) -> anyhow::Result<Vec<Discovere
        let direntry = direntry?;
        let file_name = direntry.file_name().to_string();

-        let discovered = match LayerName::from_str(&file_name) {
+        let discovered = match LayerFileName::from_str(&file_name) {
            Ok(file_name) => {
                let file_size = direntry.metadata()?.len();
-                Discovered::Layer(file_name, direntry.path().to_owned(), file_size)
+                Discovered::Layer(file_name, file_size)
            }
            Err(_) => {
                if file_name == METADATA_FILE_NAME {
@@ -72,28 +72,6 @@ pub(super) fn scan_timeline_dir(path: &Utf8Path) -> anyhow::Result<Vec<Discovere
    Ok(ret)
 }

-/// Whereas `LayerFileMetadata` describes the metadata we would store in remote storage,
-/// this structure extends it with metadata describing the layer's presence in local storage.
-#[derive(Clone, Debug)]
-pub(super) struct LocalLayerFileMetadata {
-    pub(super) metadata: LayerFileMetadata,
-    pub(super) local_path: Utf8PathBuf,
-}
-
-impl LocalLayerFileMetadata {
-    pub fn new(
-        local_path: Utf8PathBuf,
-        file_size: u64,
-        generation: Generation,
-        shard: ShardIndex,
-    ) -> Self {
-        Self {
-            local_path,
-            metadata: LayerFileMetadata::new(file_size, generation, shard),
-        }
-    }
-}
-
 /// Decision on what to do with a layer file after considering its local and remote metadata.
 #[derive(Clone, Debug)]
 pub(super) enum Decision {
@@ -102,11 +80,11 @@ pub(super) enum Decision {
    /// The layer is present locally, but local metadata does not match remote; we must
    /// delete it and treat it as evicted.
    UseRemote {
-        local: LocalLayerFileMetadata,
+        local: LayerFileMetadata,
        remote: LayerFileMetadata,
    },
    /// The layer is present locally, and metadata matches.
-    UseLocal(LocalLayerFileMetadata),
+    UseLocal(LayerFileMetadata),
 }

 /// A layer needs to be left out of the layer map.
@@ -114,42 +92,39 @@ pub(super) enum Decision {
 pub(super) enum DismissedLayer {
    /// The related layer is is in future compared to disk_consistent_lsn, it must not be loaded.
    Future {
-        /// `None` if the layer is only known through [`IndexPart`].
-        local: Option<LocalLayerFileMetadata>,
+        /// The local metadata. `None` if the layer is only known through [`IndexPart`].
+        local: Option<LayerFileMetadata>,
    },
    /// The layer only exists locally.
    ///
    /// In order to make crash safe updates to layer map, we must dismiss layers which are only
    /// found locally or not yet included in the remote `index_part.json`.
-    LocalOnly(LocalLayerFileMetadata),
+    LocalOnly(LayerFileMetadata),
 }

 /// Merges local discoveries and remote [`IndexPart`] to a collection of decisions.
 pub(super) fn reconcile(
-    discovered: Vec<(LayerName, Utf8PathBuf, u64)>,
+    discovered: Vec<(LayerFileName, u64)>,
    index_part: Option<&IndexPart>,
    disk_consistent_lsn: Lsn,
    generation: Generation,
    shard: ShardIndex,
-) -> Vec<(LayerName, Result<Decision, DismissedLayer>)> {
+) -> Vec<(LayerFileName, Result<Decision, DismissedLayer>)> {
    use Decision::*;

-    // name => (local_metadata, remote_metadata)
-    type Collected =
-        HashMap<LayerName, (Option<LocalLayerFileMetadata>, Option<LayerFileMetadata>)>;
+    // name => (local, remote)
+    type Collected = HashMap<LayerFileName, (Option<LayerFileMetadata>, Option<LayerFileMetadata>)>;

    let mut discovered = discovered
        .into_iter()
-        .map(|(layer_name, local_path, file_size)| {
+        .map(|(name, file_size)| {
            (
-                layer_name,
+                name,
                // The generation and shard here will be corrected to match IndexPart in the merge below, unless
                // it is not in IndexPart, in which case using our current generation makes sense
                // because it will be uploaded in this generation.
                (
-                    Some(LocalLayerFileMetadata::new(
-                        local_path, file_size, generation, shard,
-                    )),
+                    Some(LayerFileMetadata::new(file_size, generation, shard)),
                    None,
                ),
            )
@@ -178,7 +153,7 @@ pub(super) fn reconcile(
                Err(DismissedLayer::Future { local })
            } else {
                match (local, remote) {
-                    (Some(local), Some(remote)) if local.metadata != remote => {
+                    (Some(local), Some(remote)) if local != remote => {
                        Ok(UseRemote { local, remote })
                    }
                    (Some(x), Some(_)) => Ok(UseLocal(x)),
@@ -202,12 +177,12 @@ pub(super) fn cleanup(path: &Utf8Path, kind: &str) -> anyhow::Result<()> {
 }

 pub(super) fn cleanup_local_file_for_remote(
-    local: &LocalLayerFileMetadata,
+    path: &Utf8Path,
+    local: &LayerFileMetadata,
    remote: &LayerFileMetadata,
 ) -> anyhow::Result<()> {
-    let local_size = local.metadata.file_size();
+    let local_size = local.file_size();
    let remote_size = remote.file_size();
-    let path = &local.local_path;

    let file_name = path.file_name().expect("must be file path");
    tracing::warn!("removing local file {file_name:?} because it has unexpected length {local_size}; length in remote index is {remote_size}");
@@ -224,7 +199,7 @@ pub(super) fn cleanup_local_file_for_remote(

 pub(super) fn cleanup_future_layer(
    path: &Utf8Path,
-    name: &LayerName,
+    name: &LayerFileName,
    disk_consistent_lsn: Lsn,
 ) -> anyhow::Result<()> {
    // future image layers are allowed to be produced always for not yet flushed to disk
@@ -236,14 +211,12 @@ pub(super) fn cleanup_future_layer(
 }

 pub(super) fn cleanup_local_only_file(
-    name: &LayerName,
-    local: &LocalLayerFileMetadata,
+    path: &Utf8Path,
+    name: &LayerFileName,
+    local: &LayerFileMetadata,
 ) -> anyhow::Result<()> {
    let kind = name.kind();
-    tracing::info!(
-        "found local-only {kind} layer {name}, metadata {:?}",
-        local.metadata
-    );
-    std::fs::remove_file(&local.local_path)?;
+    tracing::info!("found local-only {kind} layer {name}, metadata {local:?}");
+    std::fs::remove_file(path)?;
    Ok(())
 }
--- a/pageserver/src/tenant/timeline/layer_manager.rs
+++ b/pageserver/src/tenant/timeline/layer_manager.rs
@@ -205,24 +205,6 @@ impl LayerManager {
        updates.flush();
    }

-    /// Called when compaction is completed.
-    pub(crate) fn rewrite_layers(
-        &mut self,
-        rewrite_layers: &[(Layer, ResidentLayer)],
-        drop_layers: &[Layer],
-        _metrics: &TimelineMetrics,
-    ) {
-        let mut updates = self.layer_map.batch_update();
-
-        // TODO: implement rewrites (currently this code path only used for drops)
-        assert!(rewrite_layers.is_empty());
-
-        for l in drop_layers {
-            Self::delete_historic_layer(l, &mut updates, &mut self.layer_fmgr);
-        }
-        updates.flush();
-    }
-
    /// Called when garbage collect has selected the layers to be removed.
    pub(crate) fn finish_gc_timeline(&mut self, gc_layers: &[Layer]) {
        let mut updates = self.layer_map.batch_update();
@@ -294,7 +276,7 @@ impl<T: AsLayerDesc + Clone> LayerFileManager<T> {
        // A layer's descriptor is present in the LayerMap => the LayerFileManager contains a layer for the descriptor.
        self.0
            .get(&desc.key())
-            .with_context(|| format!("get layer from desc: {}", desc.layer_name()))
+            .with_context(|| format!("get layer from desc: {}", desc.filename()))
            .expect("not found")
            .clone()
    }
--- a/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs
+++ b/pageserver/src/tenant/timeline/walreceiver/connection_manager.rs
@@ -1535,7 +1535,7 @@ mod tests {

        let harness = TenantHarness::create("switch_to_same_availability_zone")?;
        let mut state = dummy_state(&harness).await;
-        state.conf.availability_zone.clone_from(&test_az);
+        state.conf.availability_zone = test_az.clone();
        let current_lsn = Lsn(100_000).align();
        let now = Utc::now().naive_utc();

@@ -1568,7 +1568,7 @@ mod tests {
        // We have another safekeeper with the same commit_lsn, and it have the same availability zone as
        // the current pageserver.
        let mut same_az_sk = dummy_broker_sk_timeline(current_lsn.0, "same_az", now);
-        same_az_sk.timeline.availability_zone.clone_from(&test_az);
+        same_az_sk.timeline.availability_zone = test_az.clone();

        state.wal_stream_candidates = HashMap::from([
            (
--- a/pageserver/src/tenant/upload_queue.rs
+++ b/pageserver/src/tenant/upload_queue.rs
@@ -1,9 +1,8 @@
-use super::storage_layer::LayerName;
+use super::storage_layer::LayerFileName;
 use super::storage_layer::ResidentLayer;
 use crate::tenant::metadata::TimelineMetadata;
 use crate::tenant::remote_timeline_client::index::IndexPart;
 use crate::tenant::remote_timeline_client::index::LayerFileMetadata;
-use crate::tenant::remote_timeline_client::index::Lineage;
 use std::collections::{HashMap, VecDeque};
 use std::fmt::Debug;

@@ -46,7 +45,7 @@ pub(crate) struct UploadQueueInitialized {

    /// All layer files stored in the remote storage, taking into account all
    /// in-progress and queued operations
-    pub(crate) latest_files: HashMap<LayerName, LayerFileMetadata>,
+    pub(crate) latest_files: HashMap<LayerFileName, LayerFileMetadata>,

    /// How many file uploads or deletions been scheduled, since the
    /// last (scheduling of) metadata index upload?
@@ -57,9 +56,6 @@ pub(crate) struct UploadQueueInitialized {
    /// DANGER: do not return to outside world, e.g., safekeepers.
    pub(crate) latest_metadata: TimelineMetadata,

-    /// Part of the flattened "next" `index_part.json`.
-    pub(crate) latest_lineage: Lineage,
-
    /// `disk_consistent_lsn` from the last metadata file that was successfully
    /// uploaded. `Lsn(0)` if nothing was uploaded yet.
    /// Unlike `latest_files` or `latest_metadata`, this value is never ahead.
@@ -93,7 +89,7 @@ pub(crate) struct UploadQueueInitialized {
    /// Putting this behind a testing feature to catch problems in tests, but assuming we could have a
    /// bug causing leaks, then it's better to not leave this enabled for production builds.
    #[cfg(feature = "testing")]
-    pub(crate) dangling_files: HashMap<LayerName, Generation>,
+    pub(crate) dangling_files: HashMap<LayerFileName, Generation>,

    /// Set to true when we have inserted the `UploadOp::Shutdown` into the `inprogress_tasks`.
    pub(crate) shutting_down: bool,
@@ -175,7 +171,6 @@ impl UploadQueue {
            latest_files: HashMap::new(),
            latest_files_changes_since_metadata_upload_scheduled: 0,
            latest_metadata: metadata.clone(),
-            latest_lineage: Lineage::default(),
            projected_remote_consistent_lsn: None,
            visible_remote_consistent_lsn: Arc::new(AtomicLsn::new(0)),
            // what follows are boring default initializations
@@ -223,7 +218,6 @@ impl UploadQueue {
            latest_files: files,
            latest_files_changes_since_metadata_upload_scheduled: 0,
            latest_metadata: index_part.metadata.clone(),
-            latest_lineage: index_part.lineage.clone(),
            projected_remote_consistent_lsn: Some(index_part.metadata.disk_consistent_lsn()),
            visible_remote_consistent_lsn: Arc::new(
                index_part.metadata.disk_consistent_lsn().into(),
@@ -287,7 +281,7 @@ pub(crate) struct UploadTask {
 /// for timeline deletion, which skips this queue and goes directly to DeletionQueue.
 #[derive(Debug)]
 pub(crate) struct Delete {
-    pub(crate) layers: Vec<(LayerName, LayerFileMetadata)>,
+    pub(crate) layers: Vec<(LayerFileName, LayerFileMetadata)>,
 }

 #[derive(Debug)]
@@ -296,7 +290,7 @@ pub(crate) enum UploadOp {
    UploadLayer(ResidentLayer, LayerFileMetadata),

    /// Upload the metadata file
-    UploadMetadata(Box<IndexPart>, Lsn),
+    UploadMetadata(IndexPart, Lsn),

    /// Delete layer files
    Delete(Delete),
--- a/pageserver/src/virtual_file.rs
+++ b/pageserver/src/virtual_file.rs
@@ -10,7 +10,6 @@
 //! This is similar to PostgreSQL's virtual file descriptor facility in
 //! src/backend/storage/file/fd.c
 //!
-use crate::context::RequestContext;
 use crate::metrics::{StorageIoOperation, STORAGE_IO_SIZE, STORAGE_IO_TIME_METRIC};

 use crate::page_cache::PageWriteGuard;
@@ -616,7 +615,6 @@ impl VirtualFile {
        &self,
        buf: B,
        mut offset: u64,
-        ctx: &RequestContext,
    ) -> (B::Buf, Result<(), Error>) {
        let buf_len = buf.bytes_init();
        if buf_len == 0 {
@@ -625,7 +623,7 @@ impl VirtualFile {
        let mut buf = buf.slice(0..buf_len);
        while !buf.is_empty() {
            let res;
-            (buf, res) = self.write_at(buf, offset, ctx).await;
+            (buf, res) = self.write_at(buf, offset).await;
            match res {
                Ok(0) => {
                    return (
@@ -654,7 +652,6 @@ impl VirtualFile {
    pub async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
-        ctx: &RequestContext,
    ) -> (B::Buf, Result<usize, Error>) {
        let nbytes = buf.bytes_init();
        if nbytes == 0 {
@@ -663,7 +660,7 @@ impl VirtualFile {
        let mut buf = buf.slice(0..nbytes);
        while !buf.is_empty() {
            let res;
-            (buf, res) = self.write(buf, ctx).await;
+            (buf, res) = self.write(buf).await;
            match res {
                Ok(0) => {
                    return (
@@ -687,10 +684,9 @@ impl VirtualFile {
    async fn write<B: IoBuf + Send>(
        &mut self,
        buf: Slice<B>,
-        ctx: &RequestContext,
    ) -> (Slice<B>, Result<usize, std::io::Error>) {
        let pos = self.pos;
-        let (buf, res) = self.write_at(buf, pos, ctx).await;
+        let (buf, res) = self.write_at(buf, pos).await;
        let n = match res {
            Ok(n) => n,
            Err(e) => return (buf, Err(e)),
@@ -728,7 +724,6 @@ impl VirtualFile {
        &self,
        buf: Slice<B>,
        offset: u64,
-        _ctx: &RequestContext, /* TODO: use for metrics: https://github.com/neondatabase/neon/issues/6107 */
    ) -> (Slice<B>, Result<usize, Error>) {
        let file_guard = match self.lock_file().await {
            Ok(file_guard) => file_guard,
@@ -1093,9 +1088,8 @@ impl OwnedAsyncWriter for VirtualFile {
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
-        ctx: &RequestContext,
    ) -> std::io::Result<(usize, B::Buf)> {
-        let (buf, res) = VirtualFile::write_all(self, buf, ctx).await;
+        let (buf, res) = VirtualFile::write_all(self, buf).await;
        res.map(move |v| (v, buf))
    }
 }
@@ -1152,9 +1146,6 @@ fn get_open_files() -> &'static OpenFiles {

 #[cfg(test)]
 mod tests {
-    use crate::context::DownloadBehavior;
-    use crate::task_mgr::TaskKind;
-
    use super::*;
    use rand::seq::SliceRandom;
    use rand::thread_rng;
@@ -1186,11 +1177,10 @@ mod tests {
            &self,
            buf: B,
            offset: u64,
-            ctx: &RequestContext,
        ) -> Result<(), Error> {
            match self {
                MaybeVirtualFile::VirtualFile(file) => {
-                    let (_buf, res) = file.write_all_at(buf, offset, ctx).await;
+                    let (_buf, res) = file.write_all_at(buf, offset).await;
                    res
                }
                MaybeVirtualFile::File(file) => {
@@ -1211,11 +1201,10 @@ mod tests {
        async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
            &mut self,
            buf: B,
-            ctx: &RequestContext,
        ) -> Result<(), Error> {
            match self {
                MaybeVirtualFile::VirtualFile(file) => {
-                    let (_buf, res) = file.write_all(buf, ctx).await;
+                    let (_buf, res) = file.write_all(buf).await;
                    res.map(|_| ())
                }
                MaybeVirtualFile::File(file) => {
@@ -1286,7 +1275,6 @@ mod tests {
        OF: Fn(Utf8PathBuf, OpenOptions) -> FT,
        FT: Future<Output = Result<MaybeVirtualFile, std::io::Error>>,
    {
-        let ctx = RequestContext::new(TaskKind::UnitTest, DownloadBehavior::Error);
        let testdir = crate::config::PageServerConf::test_repo_dir(testname);
        std::fs::create_dir_all(&testdir)?;

@@ -1300,7 +1288,7 @@ mod tests {
                .to_owned(),
        )
        .await?;
-        file_a.write_all(b"foobar".to_vec(), &ctx).await?;
+        file_a.write_all(b"foobar".to_vec()).await?;

        // cannot read from a file opened in write-only mode
        let _ = file_a.read_string().await.unwrap_err();
@@ -1309,7 +1297,7 @@ mod tests {
        let mut file_a = openfunc(path_a, OpenOptions::new().read(true).to_owned()).await?;

        // cannot write to a file opened in read-only mode
-        let _ = file_a.write_all(b"bar".to_vec(), &ctx).await.unwrap_err();
+        let _ = file_a.write_all(b"bar".to_vec()).await.unwrap_err();

        // Try simple read
        assert_eq!("foobar", file_a.read_string().await?);
@@ -1351,8 +1339,8 @@ mod tests {
                .to_owned(),
        )
        .await?;
-        file_b.write_all_at(b"BAR".to_vec(), 3, &ctx).await?;
-        file_b.write_all_at(b"FOO".to_vec(), 0, &ctx).await?;
+        file_b.write_all_at(b"BAR".to_vec(), 3).await?;
+        file_b.write_all_at(b"FOO".to_vec(), 0).await?;

        assert_eq!(file_b.read_string_at(2, 3).await?, "OBA");

--- a/pageserver/src/virtual_file/owned_buffers_io/util/size_tracking_writer.rs
+++ b/pageserver/src/virtual_file/owned_buffers_io/util/size_tracking_writer.rs
@@ -1,4 +1,4 @@
-use crate::{context::RequestContext, virtual_file::owned_buffers_io::write::OwnedAsyncWriter};
+use crate::virtual_file::owned_buffers_io::write::OwnedAsyncWriter;
 use tokio_epoll_uring::{BoundedBuf, IoBuf};

 pub struct Writer<W> {
@@ -38,9 +38,8 @@ where
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
-        ctx: &RequestContext,
    ) -> std::io::Result<(usize, B::Buf)> {
-        let (nwritten, buf) = self.dst.write_all(buf, ctx).await?;
+        let (nwritten, buf) = self.dst.write_all(buf).await?;
        self.bytes_amount += u64::try_from(nwritten).unwrap();
        Ok((nwritten, buf))
    }
--- a/pageserver/src/virtual_file/owned_buffers_io/write.rs
+++ b/pageserver/src/virtual_file/owned_buffers_io/write.rs
@@ -1,15 +1,12 @@
 use bytes::BytesMut;
 use tokio_epoll_uring::{BoundedBuf, IoBuf, Slice};

-use crate::context::RequestContext;
-
 /// A trait for doing owned-buffer write IO.
 /// Think [`tokio::io::AsyncWrite`] but with owned buffers.
 pub trait OwnedAsyncWriter {
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
-        ctx: &RequestContext,
    ) -> std::io::Result<(usize, B::Buf)>;
 }

@@ -60,9 +57,8 @@ where
    }

    #[cfg_attr(target_os = "macos", allow(dead_code))]
-    pub async fn flush_and_into_inner(mut self, ctx: &RequestContext) -> std::io::Result<W> {
-        self.flush(ctx).await?;
-
+    pub async fn flush_and_into_inner(mut self) -> std::io::Result<W> {
+        self.flush().await?;
        let Self { buf, writer } = self;
        assert!(buf.is_some());
        Ok(writer)
@@ -76,15 +72,14 @@ where
    }

    #[cfg_attr(target_os = "macos", allow(dead_code))]
-    pub async fn write_buffered<S: IoBuf + Send>(
-        &mut self,
-        chunk: Slice<S>,
-        ctx: &RequestContext,
-    ) -> std::io::Result<(usize, S)> {
+    pub async fn write_buffered<S: IoBuf>(&mut self, chunk: Slice<S>) -> std::io::Result<(usize, S)>
+    where
+        S: IoBuf + Send,
+    {
        let chunk_len = chunk.len();
        // avoid memcpy for the middle of the chunk
        if chunk.len() >= self.buf().cap() {
-            self.flush(ctx).await?;
+            self.flush().await?;
            // do a big write, bypassing `buf`
            assert_eq!(
                self.buf
@@ -93,7 +88,7 @@ where
                    .pending(),
                0
            );
-            let (nwritten, chunk) = self.writer.write_all(chunk, ctx).await?;
+            let (nwritten, chunk) = self.writer.write_all(chunk).await?;
            assert_eq!(nwritten, chunk_len);
            return Ok((nwritten, chunk));
        }
@@ -109,7 +104,7 @@ where
            slice = &slice[n..];
            if buf.pending() >= buf.cap() {
                assert_eq!(buf.pending(), buf.cap());
-                self.flush(ctx).await?;
+                self.flush().await?;
            }
        }
        assert!(slice.is_empty(), "by now we should have drained the chunk");
@@ -121,11 +116,7 @@ where
    /// It is less performant because we always have to copy the borrowed data into the internal buffer
    /// before we can do the IO. The [`Self::write_buffered`] can avoid this, which is more performant
    /// for large writes.
-    pub async fn write_buffered_borrowed(
-        &mut self,
-        mut chunk: &[u8],
-        ctx: &RequestContext,
-    ) -> std::io::Result<usize> {
+    pub async fn write_buffered_borrowed(&mut self, mut chunk: &[u8]) -> std::io::Result<usize> {
        let chunk_len = chunk.len();
        while !chunk.is_empty() {
            let buf = self.buf.as_mut().expect("must not use after an error");
@@ -136,20 +127,20 @@ where
            chunk = &chunk[n..];
            if buf.pending() >= buf.cap() {
                assert_eq!(buf.pending(), buf.cap());
-                self.flush(ctx).await?;
+                self.flush().await?;
            }
        }
        Ok(chunk_len)
    }

-    async fn flush(&mut self, ctx: &RequestContext) -> std::io::Result<()> {
+    async fn flush(&mut self) -> std::io::Result<()> {
        let buf = self.buf.take().expect("must not use after an error");
        let buf_len = buf.pending();
        if buf_len == 0 {
            self.buf = Some(buf);
            return Ok(());
        }
-        let (nwritten, io_buf) = self.writer.write_all(buf.flush(), ctx).await?;
+        let (nwritten, io_buf) = self.writer.write_all(buf.flush()).await?;
        assert_eq!(nwritten, buf_len);
        self.buf = Some(Buffer::reuse_after_flush(io_buf));
        Ok(())
@@ -215,7 +206,6 @@ impl OwnedAsyncWriter for Vec<u8> {
    async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
        &mut self,
        buf: B,
-        _: &RequestContext,
    ) -> std::io::Result<(usize, B::Buf)> {
        let nbytes = buf.bytes_init();
        if nbytes == 0 {
@@ -232,8 +222,6 @@ mod tests {
    use bytes::BytesMut;

    use super::*;
-    use crate::context::{DownloadBehavior, RequestContext};
-    use crate::task_mgr::TaskKind;

    #[derive(Default)]
    struct RecorderWriter {
@@ -243,7 +231,6 @@ mod tests {
        async fn write_all<B: BoundedBuf<Buf = Buf>, Buf: IoBuf + Send>(
            &mut self,
            buf: B,
-            _: &RequestContext,
        ) -> std::io::Result<(usize, B::Buf)> {
            let nbytes = buf.bytes_init();
            if nbytes == 0 {
@@ -256,14 +243,10 @@ mod tests {
        }
    }

-    fn test_ctx() -> RequestContext {
-        RequestContext::new(TaskKind::UnitTest, DownloadBehavior::Error)
-    }
-
    macro_rules! write {
        ($writer:ident, $data:literal) => {{
            $writer
-                .write_buffered(::bytes::Bytes::from_static($data).slice_full(), &test_ctx())
+                .write_buffered(::bytes::Bytes::from_static($data).slice_full())
                .await?;
        }};
    }
@@ -277,7 +260,7 @@ mod tests {
        write!(writer, b"c");
        write!(writer, b"d");
        write!(writer, b"e");
-        let recorder = writer.flush_and_into_inner(&test_ctx()).await?;
+        let recorder = writer.flush_and_into_inner().await?;
        assert_eq!(
            recorder.writes,
            vec![Vec::from(b"ab"), Vec::from(b"cd"), Vec::from(b"e")]
@@ -293,7 +276,7 @@ mod tests {
        write!(writer, b"de");
        write!(writer, b"");
        write!(writer, b"fghijk");
-        let recorder = writer.flush_and_into_inner(&test_ctx()).await?;
+        let recorder = writer.flush_and_into_inner().await?;
        assert_eq!(
            recorder.writes,
            vec![Vec::from(b"abc"), Vec::from(b"de"), Vec::from(b"fghijk")]
@@ -309,7 +292,7 @@ mod tests {
        write!(writer, b"bc");
        write!(writer, b"d");
        write!(writer, b"e");
-        let recorder = writer.flush_and_into_inner(&test_ctx()).await?;
+        let recorder = writer.flush_and_into_inner().await?;
        assert_eq!(
            recorder.writes,
            vec![Vec::from(b"a"), Vec::from(b"bc"), Vec::from(b"de")]
@@ -319,20 +302,18 @@ mod tests {

    #[tokio::test]
    async fn test_write_all_borrowed_always_goes_through_buffer() -> std::io::Result<()> {
-        let ctx = test_ctx();
-        let ctx = &ctx;
        let recorder = RecorderWriter::default();
        let mut writer = BufferedWriter::new(recorder, BytesMut::with_capacity(2));

-        writer.write_buffered_borrowed(b"abc", ctx).await?;
-        writer.write_buffered_borrowed(b"d", ctx).await?;
-        writer.write_buffered_borrowed(b"e", ctx).await?;
-        writer.write_buffered_borrowed(b"fg", ctx).await?;
-        writer.write_buffered_borrowed(b"hi", ctx).await?;
-        writer.write_buffered_borrowed(b"j", ctx).await?;
-        writer.write_buffered_borrowed(b"klmno", ctx).await?;
+        writer.write_buffered_borrowed(b"abc").await?;
+        writer.write_buffered_borrowed(b"d").await?;
+        writer.write_buffered_borrowed(b"e").await?;
+        writer.write_buffered_borrowed(b"fg").await?;
+        writer.write_buffered_borrowed(b"hi").await?;
+        writer.write_buffered_borrowed(b"j").await?;
+        writer.write_buffered_borrowed(b"klmno").await?;

-        let recorder = writer.flush_and_into_inner(ctx).await?;
+        let recorder = writer.flush_and_into_inner().await?;
        assert_eq!(
            recorder.writes,
            {
--- a/Show More
+++ b/Show More