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After #1278, legacy hash, set, zset and stream metadata stored at its raw-key route in group L is migrated only when the node leading L also leads the user key's group P. With different leaders the row is never processed, which blocks Phase 3 of the TTL-inline design. Propose: measure the backlog (M1); let L's leader check P authoritatively and forward the rewrite, stamped by P's leader (A0b) or the TSO (Phase D) (M2); evacuate L's shadowed copies with an explicit-group delete (M3); gate Phase 3 on the measurement (M4). Owner-side scans of foreign legacy groups are rejected. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 1 files. (1 skipped: 1… | Write docstrings for the functions missing them to satisfy the coverage threshold. |
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Check name Status Explanation Linked Issues check Check skipped because no linked issues were found for this pull request. Out of Scope Changes check Check skipped because no linked issues were found for this pull request. Description Check Check skipped - CodeRabbit’s high-level summary is enabled. Title check タイトルは、レガシールート行のリーダー間移行に関するTTL-inline設計提案という主な変更内容を正確かつ簡潔に示しています。
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Write docstrings for the functions missing them to satisfy the coverage threshold.
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TestBackupLinksNoLiveClusterCode fails on main since two merges met: 3f097df (#1276) taught internal/backup to read snapshot SST ingest bundles with github.com/cockroachdb/pebble/v2/sstable, and 5678081 (#1277) forbade every github.com/cockroachdb/pebble package there. Allow exactly the sstable package. The bundles are files in pebble's sstable format, and the reader is a file-format dependency, not the live store the boundary keeps out; the rest of pebble stays forbidden. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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I ported the fix from #1278 ( Generated by Claude Code |
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… fallback Address review of the cross-leader legacy-row design: - M2 partitions rewrites by owner group; a multi-group batch is allowed only under Phase D, since no single leader can stamp it under A0b. - Batched, concurrent presence probes per owner group, and a cursor checkpoint after each batch, are convergence requirements: sequential per-row probes could exhaust the tick on the same page forever. - Budget the re-probes of rewritten rows that stay in L until M3, and ship M2 and M3 together. - Evacuating metadata does not let the dual-route fallback be retired: field, member, score and entry rows of pre-routing collections stay in L. Retiring it needs a separate all-family migration. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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…r pass Address the second review of the cross-leader design: - the plan cursor advances only over a contiguous prefix of settled rows, since owner groups interleave in scan order and their batches finish in any order; - each owner group's rewrites are chunked into transactions of at most 32 keys, the migrator's existing bound; - M1 counts accumulate per pass and are published atomically with the pass's completion epoch, invalidated on leadership change, so the Phase 3 gate never combines values from different passes. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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- Line 96: テーブルのM2要約を更新し、owner groupごとのrewrite
transactionは最大32キー単位に分割することを明記してください。カーソルは各batch完了時に単純に進めるのではなく、未settled行を飛ばさないよう連続したsettled
prefixまでのみ進める規則を記してください。
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Address the third review of the cross-leader design: - a relocation forces the metadata Put when the owner holds nothing, so an already-inline legacy row is not a silent no-op (cross-leader and same-node paths); - M3 enumerates L's raw stored page, so rows shadowed by an owner's tombstone are found, and deletes only while the current owner is a group other than L, bound to the delete's route version; - M1 does not claim the remote-owner presence split; M2 adds it; - align the M2 table row with the 32-key chunks and the settled-prefix checkpoint. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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…rsion - The group scan reports the legacy-route rows it skips, with owner group and reason, so M1 can count them and M2 can probe them. - M2 batches carry the catalog version their owners were resolved under; they are repartitioned before dispatch, or refused by the owner's leader, once the catalog moves. - M1 publishes one snapshot per group and plan, with the pass's catalog version, and counts rows deferred by staged visibility. - M4 requires every group-and-plan snapshot to share one current catalog version, and is one Phase 3 condition beside the TTL-inline design's bare-string prerequisite, not the whole gate. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
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- M3 probes in batches per owner group, deletes in explicit-group transactions of at most 32 keys, and advances its own per-plan cursor only over the contiguous settled prefix, so a page of shadowed rows cannot exhaust every tick. - M4 requires every M1 bucket to be zero, including rows whose owner is led locally and already holds a version (not yet evacuated by M3). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
… one-shot audit - Option A: bound the remote scan cost (4 x N x G_L page RPCs per tick) and add A' (delete L's copy in the same transaction): it converges, but keeps the N-fold read cost and needs the unfinished cross-group 2PC timestamp work, or Phase D. - Option B: RawVersionsVisibleAt is a new RPC; M2 batches are single-shard one-phase, which A0b forwards unstamped; Phase D is opt-in on main, and A0b is not on main yet. - Relocations carry an apply-time absence condition. OCC at readTS misses a P write below the global snapshot (G0 across groups); the condition closes that for relocations on both paths. - Explain why evacuation stays a separate single-group delete (B'). - Measure-first options: background counters, a one-shot audit RPC, an offline snapshot count. M3 ships alone if M2 turns out unnecessary. - Per-tick cost table across options, plus tests for the absence condition, the batched probe, the audit, and Jepsen seeding. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DYSs9vUWxGysn8e9ZPpw8r
…nce time - The batched presence probe is already on main: RawLatestCommitTS with key_batch, answered by VersionsExistAtOrBeforeGroupWithReadFence and called through routeHasVersionsAtOrBeforeRemote (the S3 auxiliary owner probe). M2 needs no new RawVersionsVisibleAt RPC or proto change for it, and the decoder's 1,025-key cap covers a 512-row page. - State the convergence time at the existing pace (about 16 hours per million rows of one meta family in one legacy group) and why proxyForwardTimeout never fires before the tick budget. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01M143Q9MNkB4QTCD4Zbd1M8
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Resolve the conflict in internal/backup/import_boundary_test.go by taking main's version (#1281). It allows the same Pebble sstable package that this branch's ported CI fix (ea98078) allowed. It also flags a stale allowance and pins the matching rules in TestForbiddenBackupDep. The PR's diff against main is now the design doc alone. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DYSs9vUWxGysn8e9ZPpw8r
… on learners Codex review on c6d1ffb: - D2 holds an ActiveTimestampTracker pin at its readTS and binds the whole run to one catalog version and one leadership term; a discarded run publishes nothing, so it cannot produce a false zero. - M3's plans join the TTL-inline plan rotation, so a recurring M2 workload that uses up every tick's budget cannot starve the evacuation. - The absence condition's capability gate covers learners as well as voters, through a replicated capability marker after which adding a replica without the capability is refused (the audit's A7 rule). Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01M143Q9MNkB4QTCD4Zbd1M8
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…cally led shard (#1278) ## Summary The Redis delta compactor's TTL-inline migration (`adapter/redis_ttl_inline_migrator.go`) has done no work in the server since a36dac7 ("Limit TTL migration scans to local leaders", 2026-07-22). This PR makes it run on every data group a node leads, makes the original failure mode fail safe, and adds a behavioural guard against coordinator wrappers that drop an optional capability. There were two bugs, one behind the other: 1. **The capability never reached the migrator.** The adapters hold `WithKeyVizLabel(startupGatedCoordinator{ShardedCoordinator})`. The migrator asks that value which data groups this node leads (`LocalLeaderGroupIDs`) and scans only those. The label wrapper answered `nil` when its inner lacked the method, and the startup gate never forwarded it, so the migrator planned zero scans. - **main has since fixed the forwarding** in #1277: both wrappers now embed a shared `kv.CoordinatorForwarder`. This branch is merged with main and takes that forwarder. - What this PR adds on top is the `known` contract (below). With it, a coordinator without the capability falls back to whole-prefix scans instead of planning none. 2. **The per-group scan refused every shard but the first.** Codex review found this. `ShardStore.ScanGroupAt` resolves the requested range through the route catalog, and a bare anchor prefix such as `!redis|str|` resolves to the first route only. Every other group got `ErrExplicitGroupRouteOwnerMismatch`. So on a split catalog, a node migrated at most the first route's anchors and failed every tick on the rest. This PR adds `ShardStore.ScanGroupOwnedAt` for it. ### Commits | Commit | Change | |---|---| | `main: reproduce the TTL migration losing local leader groups` | Failing regression test on the real chain: a `ShardedCoordinator` leading groups 1 and 2 and following group 3, wrapped as `main.go` wraps it. | | `kv, main, adapter: keep local leader groups through the coordinator wrappers` | The capability becomes `kv.LocalLeaderGroupsCoordinator` with `LocalLeaderGroupIDs() (ids []uint64, known bool)`. Decorators forward through `kv.LocalLeaderGroupIDsThrough`, which reports a coordinator without it as unknown. Unknown falls back to the migrator's existing whole-prefix `ScanAt` and logs once. A known empty list still plans nothing. | | `main: guard every ShardedCoordinator capability through the startup wrappers` | Behavioural guard test (see the wrapper section). | | `main: forward LinearizableReadForKey through the startup gate` | Superseded by main's forwarder in the merge. | | `adapter: reproduce TTL migration refusing every shard but the first` | Failing regression test over a **real** `ShardStore` split at `m` across two groups. | | `kv, adapter: scan each local leader group's own share of the TTL anchors` | New `ShardStore.ScanGroupOwnedAt`, used by the migrator's per-group plans. | | `kv, adapter: reproduce the group-owned scan's staged, bound and legacy gaps` / `kv, adapter: bound the group-owned scan, defer staged routes, serve legacy rows` | Codex round 2: one physical page per call, staged routes deferred, legacy-route rows served. | | `Merge main into feature/focused-pascal-dbr58v` | Takes main's `CoordinatorForwarder`. Moves the `known` contract onto it. Updates main's chain and plan tests to the new signature. Reworks the behavioural guard to use main's `shardedMethodsNotForwarded` list. | | `kv, adapter: reproduce legacy-route rows served against the owner's state` / `kv: serve legacy-route rows only while the logical owner holds none` | Codex round 3: legacy stream metadata. Also fixes a key the owner also holds being served by two groups. | | `adapter: reproduce TTL-inline ticks starving later scan plans` / `adapter: rotate TTL-inline scan plans across ticks` | Codex round 3: plans rotate across ticks that run out of budget. | | `kv: reproduce the group-owned scan re-reading every wide-column row` / `kv: skip the point-read pass for rows the group-owned scan serves` | Self-review: the scan no longer re-reads each served wide-column row through the point-read path (see below). | | `backup: allow pebble's sstable reader through the import boundary` | CI fix, ported from main's breakage. `TestBackupLinksNoLiveClusterCode` fails on main since 3f097df (#1276) added a pebble `sstable` reader to `internal/backup`, while 5678081 (#1277) forbade all of pebble there. The commit allows exactly the `sstable` package. | ### `ShardStore.ScanGroupOwnedAt` `ScanGroupOwnedAt(ctx, groupID, start, end, limit, ts) (rows, resume, err)`: - **One physical page per call.** Reads up to `limit` rows from the group's own store, fenced like the other explicit-group reads. `resume` is the last key the page read when it was full, `nil` once the range is exhausted. The migrator moves its cursor to `resume`, so a page with no served rows still advances. Each tick stays within one page per plan. - **Served rows only.** - **Owned rows:** keys whose route the group owns, judged by the same `routeAndGroupForKey` that routes writes. - **Legacy-route rows:** hash, set, zset and stream rows still stored at the route of their raw key. These are served only while the logical owner holds no version of the key at `ts`, as checked by this node as the owner's leader. That is exactly when a point read falls back to the legacy route (`routeMissStopsPointFallback`), so the row is the value a reader sees. The legacy route candidate is `legacyPointRouteKey`, the one point reads use. - **Skipped:** copies of ranges the group no longer owns. No key is rewritten from a stale value. - **No point-read pass.** Other scans re-read every hash, set and zset row through the point-read path. That pass now runs once in `scanRouteAtForwardPage`, after whichever page path ran, so those scans are unchanged. `ScanGroupOwnedAt` skips it, because every row it serves already carries the point-read value. This removes: - one point read per owned wide-column row; - a proxied read per legacy-route row the scan then dropped; - a page failure when such a row's owner had no known leader. - **Staged routes deferred.** A key whose route is under staged visibility is skipped and picked up on a later pass. An older live copy must not feed a rewrite while a newer staged copy waits for promotion. - **Meant for the group's own leader.** If leadership moves between planning and the scan, the forwarded request is served as `ScanGroupAt` and may be refused for one tick. The next tick replans. **Known limit, handled in the separate design PR #1280.** A legacy row in group L whose user key belongs to group P, where a different node leads P, is not migrated here. - **Why:** only P's leader may write the key (the HLC rule), and only P's leader can tell whether P holds it. Per-group plans never let P's leader read L. - **Plan:** #1280 proposes measuring the backlog first. L's leader then asks P's leader whether P holds the key and forwards the rewrite, with its timestamp issued by P's leader (A0b) or the TSO (Phase D). Finally L's shadowed copies are evacuated. - **History:** main has not migrated these rows since a36dac7. Before it, every node's whole-prefix scan reached them. - **Meanwhile:** reads stay correct through the dual-route point-read fallback and the legacy TTL fallback. Phase 3 (disabling the fallback) must wait until this case is covered or shown empty. ### Plan rotation Every plan (one per handler and local leader group) shares the compactor's per-tick budget. `migrateTTLInlineOnce` now flattens the plans into one list per tick and starts at the plan after the last one the previous tick ran, as `compactBackgroundHandlers` already does for its handlers. A tick that runs out of budget hands the rest of the rotation to the next tick, so no handler or group starves. ### Design choices - **`known` on main's forwarder.** `CoordinatorForwarder.LocalLeaderGroupIDs` returns `LocalLeaderGroupIDsThrough(Inner)`. Without `known`, any forwarder over an inner that lacks the capability turns "my inner doesn't say" into "leads no group", the failure mode of bug (1). This matches main's own fallbacks for single-group coordinators, such as `IsLeaderForGroup` falling back to the inner's leadership. - **Presence check over canonicalization for legacy rows.** With the owner-holds-nothing rule, the raw row is already the canonical value. Streams therefore need no value-reading canonicalization, and a key the owner also holds is migrated once, by the owner's plan. ### Behavior change - **Production:** each node migrates the TTL anchors of every data group it leads, in rotation. Each plan scans at most 512 physical rows per tick (30s) and rewrites at most 32 keys per proposal, under the existing 5s tick budget and 1m timeout backoff. Expect migration writes after rollout in proportion to the legacy backlog. - **API:** - `ShardedCoordinator.LocalLeaderGroupIDs` and `CoordinatorForwarder.LocalLeaderGroupIDs` now return `([]uint64, bool)`. - New `ShardStore.ScanGroupOwnedAt`. - Existing `ShardStore` behaviour is unchanged. - **Fail-safe:** if a coordinator does not report its groups, the migrator logs `ttl inline migrator: coordinator does not report local leader groups; falling back to whole-prefix scans` once, then runs one `ScanAt` per prefix. That path is not new and is not reached in the server. ## Wrapper capability guard Since #1277, both wrappers embed `kv.CoordinatorForwarder`, which closed every gap in this PR's original audit: - `LinearizableReadForKey` on the gate; - `EnsureMutationsWriteAllowed`, `ObserveForwardedRequests`, `RaftMembers*`, `PhaseD*` and `ValidateDurableTimestamp` on the label. The two guard tests check different things: - **main's `TestAdapterCoordinatorWrappersForwardShardedCapabilities`** checks that every `ShardedCoordinator` method not listed in `shardedMethodsNotForwarded` exists on both wrappers with the same signature. - **This PR's `TestStartupWrappersForwardShardedCoordinatorCapabilities`** uses the same list. It also calls each forwarded method through `startupGatedCoordinator` and through `WithKeyVizLabel(startupGatedCoordinator)` against a spy, and requires the call to reach the spy and return the spy's result and error: 30 methods × 2 wrappers. That second check catches the bug-(1) class, a method that exists but probes its inner through an interface that no longer matches. In a mutation test, I put the forwarder's `LocalLeaderGroupIDs` probe back on the old `[]uint64` signature. This test, the chain test and the wiring test all failed; the signature test passed. ## Do nodes need a one-off migration catch-up? No. The regular loop is the catch-up. - **Cursors reset on restart.** Migration cursors live only in memory, so a restart with this fix starts every per-group cursor at the top of each prefix. The rotation then cycles through every handler and locally led group. - **Reads stay correct meanwhile.** The stock server never disables the legacy `!redis|ttl|` read fallback; `WithRedisLegacyTTLReadFallback` is not wired to any flag or env var. - **What stalled and now resumes:** - rewriting legacy anchors into the inline format; - repairing the `!redis|ttl|` index; - physically cleaning up expired TTL-indexed legacy collections. This one affects storage, not correctness. - **Caveats:** - Time elapsed since 2026-07-22 says nothing about migration progress. Count from this rollout before considering Phase 3 (disabling the fallback). - On split catalogs, the whole-prefix `ScanAt` reaches only the first route for string, HLL, TTL-index and list anchors. So anchors outside the first route may never have been migrated at all, not just since 2026-07-22. This PR covers them. - The different-leader legacy case above stays unmigrated, and Phase 3 must wait for #1280. - Nothing signals that a full pass has finished; I suggest adding that as a follow-up. ## Test evidence - **Each fix was preceded by a failing test:** - The wrapper chain loses the groups: `expected []uint64{0x1, 0x2}`, `actual []uint64(nil)`. - The split store refuses group 2: `explicit group read does not own the requested key range`, for all eight prefixes. - The staged-route key was returned. - A scan read 7 rows for `limit=2`. - A legacy-route hash row was dropped. - A legacy stream meta row was dropped, and the compactor left its TTL out (`ExpireAt:0x0`). - A hash key the owner also held was served by both groups. - 24 budget-limited ticks scanned the first of 24 plans 24 times. - Three owned hash rows cost three point reads. - A legacy hash row whose owner had no leader failed the page with `leader not found`. - **Mutation checks:** each of these fails its targeted tests: - dropping the owner presence check, or narrowing the legacy candidate back to wide-column keys; - ignoring "cannot answer"; - always starting the rotation at plan 0; - putting the forwarder's `LocalLeaderGroupIDs` probe back on the old signature. - **Race suites:** `go test -race -count=1 ./adapter/... ./kv/... .` on `a73a7c0a`: adapter ok (233s), kv ok (14s), root ok (46s). - **Lint:** golangci-lint v2.9.0, CI's version, with main's config (now including `cyclop`): `0 issues`. - **End to end:** one process hosting groups 1 and 2 split at `m`, with a legacy string plus a legacy `!redis|ttl|` anchor seeded on each side. | Binary | Group 1 key | Group 2 key | "does not own" errors | compactor pass failures | |---|---|---|---|---| | PR at `35f698e` (before the split-store fix) | migrated | still legacy after 100s | 4 | 3 | | PR at `a73a7c0a` (merged with main) | migrated | migrated (both within 30s) | 0 | 0 | `TTL` and `GET` were correct throughout. An earlier single-group run (3 nodes) showed base `184351ae` still legacy after 100s, while this PR migrated within 30s. - **Jepsen:** on a 3-node cluster running `a73a7c0a`, the same workloads as CI with `--time-limit 60 --rate 10 --concurrency 10`: - `elastickv.redis-workload`: `{:valid? true}`, 603 ok / 0 fail / 2 info. - `elastickv.redis-zset-safety-workload`: `{:valid? true}`, 586 ok / 0 fail / 2 info. - Zero migrator, ownership or panic lines in the node logs. - These workloads write only inline-format data, so the migrator scans each group concurrently with them but has nothing to rewrite. The end-to-end runs cover the rewrite. ## Self-review (five lenses) 1. **Data loss:** - Migration writes are OCC transactions at the scan's `readTS`, with a commit timestamp from `kv.NextTimestampAfterThrough` on the dispatching group leader (`dispatchCompaction`). A user write after `readTS` conflicts rather than being overwritten. - The scan hands the migrator only rows whose value is the one a reader sees: owned rows, and legacy-route rows the owner holds no version of. Never stale copies of moved ranges, never live copies of a route under staged visibility, never a legacy copy the owner has superseded or deleted. - Rotation changes only the order of plans. - No change to Raft apply, snapshots, Pebble sync or retention. 2. **Concurrency / distributed:** - `LocalLeaderGroupIDs` is a point-in-time snapshot. Each key is still checked with `IsLeaderForKey` before dispatch. - The owner presence check runs only on the owner's leader, behind the same lease fence point reads use. Elsewhere the row is skipped. - A leadership change between the check and the dispatch is caught by `IsLeaderForKey` and OCC. - The rotation cursor is guarded by `stateMu`. Concurrent `SyncOnce` calls only shift where a tick starts. - The one-time warning uses `sync.Once`. Race tests pass. 3. **Performance:** - One physical page per scan call, plus one in-memory route lookup per row. A legacy-route row adds one local version probe. - No per-row point reads; the shared page path keeps its point-read pass for every other caller. - Rotation adds no reads; it builds handlers × local-groups plan structs per tick. - Followers scan nothing. The Redis request path is unchanged. 4. **Data consistency:** - The page and the presence check both read at `readTS`. The presence rule mirrors the point-read fallback exactly, including tombstones. - Ownership uses the same resolution as writes. - The new code issues no timestamps and does not touch the route catalog. - Keeping known-empty distinct from unknown keeps followers from scanning. - TLA+ anchors (`kv/coordinator.go`, `kv/sharded_coordinator.go`): the change adds a capability interface and helper and changes `LocalLeaderGroupIDs`' return. Nothing in the HLC-4, renewal-cadence, group-selection, fail-closed or OCC checklist changed, so no spec update is needed. 5. **Test coverage:** - Regression tests for every bug and review finding: wrapper chain, real split `ShardStore`, staged routes, physical bound, legacy-route rows (hash and stream, three owner states, owner led elsewhere), legacy stream migration end to end in the compactor, plan rotation, no point reads for served rows. - The behavioural guard test and mutation checks. - End-to-end runs on real binaries and the Redis Jepsen workloads. ## Risk Low to moderate. This turns back on a background writer that has been dormant in production for about three months, and on split catalogs it reaches parts of the keyspace it never reached before. Its writes are OCC-guarded and rate-bounded. Watch Raft proposal load on group leaders during the first pass after rollout. 🤖 Generated with [Claude Code](https://claude.com/claude-code) https://claude.ai/code/session_019P5kzueGgfe3F5iSe8TMtC
…fore M3 Codex review on f6bb7a0: - SyncOnce runs the delta-compaction handlers first and migrates only with budget left, so sustained delta load starves every TTL-inline plan, M1's counting included. M1 merges both loops into one top-level rotation. - The absence condition becomes its own milestone (M1b), applied to the same-node relocation path independently of cross-leader forwarding. M3 ships after M1b, never before, since it deletes L's copy after relocations the same-node path already performs. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01M143Q9MNkB4QTCD4Zbd1M8
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Design: docs/design/2026_10_17_proposed_ttl_inline_cross_leader_legacy_rows.md
Summary
This PR adds only a design doc. It carried a CI fix ported from main's breakage, which allowed pebble's
sstablepackage through the backup import-boundary test. Main has since landed its own fix (#1281), and the merge of main takes main's version of that file, so the PR's diff against main is now the doc alone.#1278 makes each node migrate TTL anchors only in the groups it leads. Some hash, set, zset and stream metadata is still stored at the route of its raw key, in group L, while its user key belongs to group P. That PR migrates such a row only when the same node leads both L and P.
When different nodes lead them, nothing processes the row:
Those rows keep their legacy TTL anchors. That blocks Phase 3 of the TTL-inline design, which disables the
!redis|ttl|read fallback. The maintainer decided to handle this case in a separate design.Options compared
Proposal
readTSand is discarded if the catalog or leadership changes mid-run. M1 also merges the delta-compaction handlers and the migration plans into one top-level rotation, so sustained delta load can no longer starve migration.readTSmisses a P write below the global snapshot, while the condition rejects the relocation whenever P holds any version. It is a new mutation field, gated on a capability marker that P replicates once every voter and learner supports it; after the marker, a replica lacking the capability cannot join. It applies first to the same-node relocation path of #1278 and needs no cross-leader forwarding.RawLatestCommitTS(key_batch) already on main, so it needs no new RPC. If P holds nothing, L's leader forwards the rewrite in single-shard transactions of at most 32 keys per owner group, each carrying M1b's absence condition. The timestamp is issued by P's leader under A0b, or by the TSO under Phase D. Batches are bound to their catalog version, a relocation always writes, and the cursor advances only over the contiguous settled prefix. M2 stays off unless M1b's marker is in place and A0b or Phase D holds.Delwould be routed to P). It deletes only when the current owner is a group other than L and holds a version, at the delete's route version. It is batched and checkpointed like M2, and its plans share the TTL-inline plan rotation so M2 cannot starve it. It ships with M2, or without M2 if M1 shows M2 is not needed, but never before M1b.§5 has a per-tick cost table for every option, and the convergence time at the existing pace: about 16 hours per million rows of one meta family in one legacy group. Retiring the dual-route point-read fallback is out of scope: auxiliary field, member, score and entry rows of pre-routing collections stay in L.
Review focus
pb.Mutationfield or a transaction-level key list (open question 3), and its capability-gated rollout as M1b.Self-review (five lenses)
This PR only adds a doc, so each lens applies to the design rather than to code:
readTSand must find P empty at apply, so a user write that lands below the global snapshot is never overwritten. The guard ships before any evacuation (M1b before M3). A relocation forces itsPut. M3 deletes only copies that a distinct owner shadows, inside L's current route, at a pinned route version.🤖 Generated with Claude Code
https://claude.ai/code/session_01M143Q9MNkB4QTCD4Zbd1M8