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fix(lancedb): reclaim stale versions via write-locked prune - #379

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fix(lancedb): reclaim stale versions via write-locked prune#379
gloryfromca wants to merge 7 commits into
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pr/lancedb-prune-under-lock

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@gloryfromca gloryfromca commented Jul 31, 2026

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Consolidated LanceDB hardening PR. Folds in #354 / #355 / #357 (now closed) plus the prune-under-lock storage fix + cascade health, all rebased on latest main. This mirrors the code the endurance soak actually exercised.

Commits

The prune-under-lock fix (why)

A storage-endurance soak (~100h across three runs, sustained churn + fault injection) reproduced the disk-bloat root cause: the bundled lock-free optimize(cleanup_older_than=...) loses its commit-conflict race against concurrent writes, so cleanup ran only 16 of ~250 times and superseded dataset versions piled up until the index dir hit the 40G disk guardrail and never reclaimed under load.

Split the maintenance path:

  • LanceRepoBase.optimize() — compact-only, lock-free (a Retryable commit conflict here is benign; the next beat retries, so it must not stall writers).
  • LanceRepoBase.prune(older_than) — new; cleanup_older_than + delete_unverified=True under the per-table write lock (no writer in flight → the Rewrite owns the manifest → cleanup completes every beat; aggressive deletion is safe). Also removes empty _indices/<uuid>/ husks (soak: 13061 dirs, 98% empty), threaded.
  • Cascade worker: heavy beat calls prune(), light beat optimize(). Benign light-beat conflict → debug, doesn't count toward the failure streak or trigger a fallback rebuild.
  • Prune retention decoupled from the prune cadence, defaulted to 60s (runs under the lock → only needs to outlive an in-flight read).

Plus cascade observability: CascadeOrchestrator.health()CascadeHealth, surfaced as a typed cascade block on GET /health. healthy = operational only (drain / optimize / prune); failed_permanent is an informational count that does not flip healthy.

Soak result

  • Disk bounded & fully reclaimable — sawtooths under load, reclaims to live size (~1.3G); 42G → 1.3G in 10 min once writes pause. vs run1 stuck at 40G until idle.
  • 0 crashes / 0 OOM / 0 stuck cleanups across all runs. lance reports 2 live fragments / ~625MB per table.

Full write-up (code + conditions + results, with figures): DlabDev wiki → "EverOS LanceDB 存储浸泡测试 — 最终报告".

Tests

make lint + import-linter + dump_openapi.py --check + full unit suite (1882 passed).

Follow-up (not in this PR)

Embedding/vector errors during cascade indexing are currently classified permanent (retryable=False); the soak's fuzz showed a transient embedder blip permanently fails a file. Candidate: reclassify as RecoverableError.

Co-Authored-By: Claude Opus 4.8 noreply@anthropic.com

🤖 Generated with Claude Code

zhanghui and others added 7 commits July 30, 2026 17:26
The storage soak (48h, sustained churn + fuzz) proved the bundled
lock-free `optimize(cleanup_older_than=...)` loses its commit-conflict
race against concurrent writes — cleanup ran only 16 of ~250 times, so
old dataset versions / FTS orphans piled up and the index dir grew to
the 40G disk guardrail and never reclaimed under load. main still had
that bundled call.

Split the maintenance path:
- `LanceRepoBase.optimize()` is now compact-only and lock-free (a commit
  conflict here is benign — the next beat retries, so it must not stall
  writers).
- `LanceRepoBase.prune(older_than)` runs `cleanup_older_than +
  delete_unverified=True` **under the per-table write lock**, so no
  writer is in flight: the Rewrite has the manifest to itself (cleanup
  completes every beat) and aggressive deletion is safe. It also removes
  the empty `_indices/<uuid>/` husks cleanup leaves behind (soak: 13061
  dirs, 98% empty), offloaded to a thread.
- The cascade worker's heavy beat calls `prune()`; the light beat calls
  `optimize()`. A benign light-beat commit conflict is logged at debug
  and does not count toward the failure streak or trigger a rebuild.
- Prune's retention window (`cleanup_older_than`) is decoupled from the
  prune cadence and defaulted short (60s). It runs under the write lock,
  so the window only needs to outlive an in-flight read; keeping it =
  cadence (300s) left ~2 cadences of superseded full-table copies on
  disk between beats (soak: transient ~15G/table peaks). 60s reclaims
  all but the last minute each beat — same live floor (~625MB/table),
  far lower transient footprint.

Result on the re-run soak: disk sawtooths and reclaims to live-data size
(~1.3G total) under active load — vs run1 stuck at 40G until writes
stopped — with 0 crashes / 0 OOM / 0 stuck cleanups over 48h.

Cascade projection health is now observable:
- `CascadeOrchestrator.health()` -> `CascadeHealth`, combining the
  worker's in-memory signals (drain-loop failures, unrecoverable count,
  optimize streak, prune staleness) with the SQLite queue summary.
- `GET /health` gains a typed `cascade` readiness block. `healthy`
  reflects operational health only (drain / optimize / prune);
  `failed_permanent` (files awaiting `cascade fix`) is a data-quality
  backlog reported as an informational count that does NOT flip
  `healthy` — otherwise the signal would sit red permanently.

The scanner-side retry cap and the `_MAX_TOTAL_RETRIES` budget already
on main handle re-enqueue storms, so no duplicate is added here.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The previous open-ended `>=0.13.0` let any environment float to an
untested release, including 0.32-0.34 which carry a compaction
offset-overflow regression (lance-format/lance#7653) that stalls
version cleanup and grows the index dir without bound.

- Floor 0.34.0: the current resolved version; runs safely thanks to
  the with_position=False FTS workaround shipped in #336. Verified that
  data written by lancedb 0.32.0 (lance v6) reads correctly under
  0.34.0 (lance v8), so existing deployments upgrade cleanly. Never
  widen the floor below 0.34 -- older lance cannot read v8-format data.
- Ceiling <0.35.0: 0.35 embeds lance-rust v9 (large encoding jump, not
  yet stable-released); it must pass the soak harness before we allow
  it.

Resolved version is unchanged (still 0.34.0); this only tightens the
declared constraint.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
(cherry picked from commit 94f9aa6)
The agent AGENTIC path (`agent_case` / `agent_skill`) fed recall
candidates straight into `aagentic_retrieve`, whose `_format_docs`
(LLM sufficiency / multi-query prompt) reads `metadata["episode"]` as a
`{subject, content}` dict plus a ms-epoch `timestamp`. Agent-kind rows
carry their body in the recaller's `text_field` and time as a datetime,
so `_format_docs` raised `TypeError: Candidate ... has no episode dict`
and `POST /api/v*/memory/search` returned 500 for any
`owner_type=agent` + `method=agentic` request.

Mirror the episode path's bridge: reshape agent candidate metadata into
the everalgo doc contract before `aagentic_retrieve`, and revert it
before DTO shaping so the agent shapers still see a datetime timestamp.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit bb9a3a5)
The committed `search_seed` fixture and several search e2e tests were
written for the pre-1.5 memcell fact-linkage model. Current extraction
links atomic_facts to episodes via `parent_id == episode.entry_id`
(parent_type="episode"), and user_memory clusters store episode
entry_id members — so the stale fixture made VECTOR/AGENTIC recall and
the cluster-narrowing path find nothing, and stale assertions checked
an old error code.

- Regenerate `search_seed/*` from a fresh corpus in the current
  entry_id format; facts now bridge across multiple episodes (richer
  agentic / hierarchical-eviction coverage).
- Fix `_dump_search_seed.py` sampling: pick episodes that host facts
  first and keep facts by episode entry_id, so re-dumps stay coherent.
- Migrate e2e tests to the entry_id model (hierarchical-eviction,
  session/timestamp filters, cluster seeding helper) and update the
  filter-error assertion to the current `INVALID_INPUT` code.
- Provision `ome.toml` in the full-app pipeline fixture (the OME config
  reloader requires it; strategies are code-registered so the packaged
  default suffices), unblocking corpus regeneration.

Full search e2e suite now green (49/49).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
(cherry picked from commit 44cd9ce)
verify_business_schemas only compared column names, so a column whose
on-disk Arrow type had drifted (name unchanged) slipped through and
detonated later inside merge_insert as an opaque LanceError(IO)
"Spill has sent an error" (#337). Now compare each shared column's Arrow
type against schema.to_arrow_schema() — the exact schema get_table
builds tables from, so a healthy table never false-positives.

Reproduced #337 byte-identically: an episode.subject_vector column left
as string or null by an older build, plus a real 1024-d vector on
upsert, yields the exact crash. No lancedb version (0.13-0.34) renders
Optional[Vector] as a non-vector type, so the startup guard is what
should catch it — not the runtime.

Add `everos cascade rebuild` as the safe recovery: it drops the business
LanceDB tables and re-indexes from markdown, skipping the verify guard
(which the drift would otherwise trip on startup). Unlike removing only
.index/lancedb it re-populates already-done entries (reset_all clears
the cascade queue); unlike removing all of .index it preserves
unprocessed_buffer (messages not yet extracted).

Fixes #337.
Add the `everos cascade rebuild` command to the runbook, CLI, and
how-memory-works docs. Correct the old recovery guidance: a bare
`rm -rf .index/lancedb` leaves md_change_state marked `done`, so the
scanner skips those files and the index comes back empty — the runbook
previously claimed a full repopulation that does not happen. `cascade
rebuild` is the safe path (re-populates done entries, preserves
unprocessed_buffer). Also document that verify now checks column types.
CascadeOrchestrator dropped the embedder param when embedding became a
soft dependency (main); fold the schema-drift integration test onto it.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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