Fix #1929: Bug: /api/v1/embeddings/maintenance causes 100% CPU and event loop starvation on

[Memtensor-AI]

Description

Fixes MemOS#1929 (100% CPU + event-loop starvation on GET /api/v1/embeddings/maintenance) inside the TypeScript subproject apps/memos-local-plugin. Root cause: computeEmbeddingMaintenanceStats() walked every row of traces/policies/world_model/skills with the full BLOB vector columns selected, then decoded each vector into a Float32Array only to read its .length. On a 93K-trace corpus that allocated ~270MB of heap per call and blocked the Node main thread for 4+ minutes.

Primary fix: added embeddingMaintenanceStats(expectedByteLength) to each of the four vector-bearing repos plus a Repos.embeddingMaintenanceStats(expectedDim) aggregator. The new path uses SELECT COUNT(*), SUM(CASE WHEN ...) with LENGTH(blob) for the dim check — no BLOB ever crosses the better-sqlite3 boundary. The trace path mirrors the existing eligibility filter (shouldTraceHaveEmbeddings) and the lightweight-memory exclusion on vec_action in SQL using LENGTH(TRIM(...)) and the established instr(tags_json, '"lightweight_memory"') pattern. computeEmbeddingMaintenanceStats() now takes the SQL fast path whenever embedder.dimensions > 0; the legacy JS walk stays as a fallback for the "no embedder configured" case so dimension inference still works for rebuildEmbeddings.

Secondary fix (opt-in): added algorithm.retrieval.vectorScanMaxAgeMs config field (default 0 = disabled, range 0..365d). When > 0, tier-2 traces.searchByVector pre-filters by ts >= now - vectorScanMaxAgeMs at the SQL layer, bounding the per-turn brute-force scan reported as a separate 5-30s blocking issue. Older memories still surface via the FTS / pattern channels which already run in parallel.

Verification: tsc -p tsconfig.json --noEmit exits 0. vitest run tests/unit → 1045 pass / 1 skip / 2 pre-existing failures (page-clamp + migrator schema drift, both reproduce on a clean base-branch checkout). Integration suite passes. New coverage: 4 SQL-COUNT tests in tests/unit/storage/embedding-maintenance-stats.test.ts and 1 time-window test in tests/unit/retrieval/tier2.test.ts. The 28 existing pipeline tests now exercise the SQL path end-to-end (test embedder advertises dimensions=384), proving the SQL path returns identical counts to the JS-walk on the same seeded dataset.

Related Issue (Required): Fixes #1929

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactor (does not change functionality, e.g. code style improvements, linting)
• Documentation update

How Has This Been Tested?

Automated tests are pending.

• Unit Test
• Test Script Or Test Steps (please provide)
• Pipeline Automated API Test (please provide)

Checklist

• I have performed a self-review of my own code
• I have commented my code in hard-to-understand areas
• I have added tests that prove my fix is effective or that my feature works
• I have created related documentation issue/PR in MemOS-Docs (if applicable)
• I have linked the issue to this PR (if applicable)
• I have mentioned the person who will review this PR

@MatthewZhuang, @CarltonXiang, @syzsunshine219, @World-controller please review this PR.

Reviewer Checklist

• closes Bug: /api/v1/embeddings/maintenance causes 100% CPU and event loop starvation on large corpora #1929
• Made sure Checks passed
• Tests have been provided

[Memtensor-AI]

❌ Automated Test Results: FAILED

Auto-fix retry 1/2 triggered.

Failed tests:

• test_out_of_range_rejected_or_clamped_to_valid[negative_1]
• test_out_of_range_rejected_or_clamped_to_valid[negative_60s]
• test_out_of_range_rejected_or_clamped_to_valid[negative_one_day]
• test_out_of_range_rejected_or_clamped_to_valid[max_plus_1]
• test_out_of_range_rejected_or_clamped_to_valid[max_plus_one_day]
• test_out_of_range_rejected_or_clamped_to_valid[hundred_x_max]
• test_invalid_type_does_not_crash_or_corrupt[string_number]
• test_invalid_type_does_not_crash_or_corrupt[string_text]
• test_invalid_type_does_not_crash_or_corrupt[none_value]
• test_invalid_type_does_not_crash_or_corrupt[bool_true]

Error details

Tests failed. Failed cases: test_out_of_range_rejected_or_clamped_to_valid[negative_1], test_out_of_range_rejected_or_clamped_to_valid[negative_60s], test_out_of_range_rejected_or_clamped_to_valid[negative_one_day], test_out_of_range_rejected_or_clamped_to_valid[max_plus_1], test_out_of_range_rejected_or_clamped_to_valid[max_plus_one_day]

Branch: bugfix/autodev-1929

[Memtensor-AI]

❌ Automated Test Results: FAILED

Auto-fix retry 1/2 triggered.

Failed tests:

• test_out_of_range_rejected_or_clamped_to_valid[negative_1]
• test_out_of_range_rejected_or_clamped_to_valid[negative_60s]
• test_out_of_range_rejected_or_clamped_to_valid[negative_one_day]
• test_out_of_range_rejected_or_clamped_to_valid[max_plus_1]
• test_out_of_range_rejected_or_clamped_to_valid[max_plus_one_day]
• test_out_of_range_rejected_or_clamped_to_valid[hundred_x_max]
• test_invalid_type_does_not_crash_or_corrupt[string_number]
• test_invalid_type_does_not_crash_or_corrupt[string_text]
• test_invalid_type_does_not_crash_or_corrupt[none_value]
• test_invalid_type_does_not_crash_or_corrupt[dict_value]

Error details

The vector_scan_max_age field in the memos_local_plugin accepts and persists invalid values (negatives, out-of-range integers, and non-numeric types) via PATCH without rejection or clamping, violating the schema contract that GET must return a value within [0, 31536000000].

Branch: bugfix/autodev-1929