tidaldb/docs
jx12n a0399550d6 feat(m12p6): persist HNSW graph + bounded SIGTERM drain — boot loads, no rebuild
Boot now LOADS the per-slot HNSW graph instead of rebuilding it. Clean
shutdown writes {data_dir}/vector/<kind>__<slot>.usearch; the next open loads
it when it matches the durable corpus (seconds), falling back to a full rebuild
only when the graph is missing/stale/corrupt. Eliminates the multi-minute boot
rebuild (~50-70 min at 1M/1536-D) that let the WAL compact past a restarting
node and triggered the reseed cascade.

Graceful SIGTERM now actually runs the close: bounded_drain caps the post-signal
HTTP drain (TIDAL_SHUTDOWN_DRAIN_MS, default 15s) then runs the deterministic
close regardless — sibling keep-alive connections no longer block the drain past
the k8s 60s grace into a SIGKILL (which cannot run Drop). ClusterNode and
ShardReplica::shutdown are now &self (db handle is an ArcSwapOption) so the close
fires even when a stuck connection task holds an Arc.

Fix USearch insert to be a true upsert (remove+add): it was unconditional add,
which a multi:false index rejects on a reseeding follower's post-snapshot WAL
replay -> applied_events stalls -> catch-up deadlock -> unrecoverable cluster.

Also: circuit-breaker peer last-contact tracking; real k3s 1536-dim deploy +
recall findings (recall@10 0.9869, read p99 8.71ms @ 200rps @ 100k) in
docs/profiling/m12-cluster-deploy-findings.md; new tidal-stress k8s jobs and
m12p6 graph-persistence + SIGTERM tier-3 regression tests.
2026-06-15 13:09:20 -06:00
..
guides feat(m11): cluster security (m11p7) + perf instrumentation floor 2026-06-13 01:25:35 -06:00
ops bench(1536): production-shape capacity — read path is cheap, quorum write is the ceiling 2026-06-13 21:40:58 -06:00
planning feat(m11): sharding × replication + rebalancing (m11p6 L3-L5) 2026-06-13 18:23:43 -06:00
profiling feat(m12p6): persist HNSW graph + bounded SIGTERM drain — boot loads, no rebuild 2026-06-15 13:09:20 -06:00
research chore: doc consolidation, seven-dimension review fixes, and commit hooks 2026-06-08 22:46:28 -06:00
reviews feat(m11): observability+ops (m11p8) + perf-sweep wave 2 T2 2026-06-13 09:17:49 -06:00
runbooks fix(m12p6): T4 TLS scale-up enablement — https seed-join via ready-only Service + up-front rustls provider 2026-06-14 20:29:37 -06:00
specs feat(m12): vector retrieval G1/G2 — recall harness, ANN in RETRIEVE, index tuning 2026-06-14 11:07:09 -06:00
content-strategy.md feat: complete Milestone 5 — full-text search, RRF fusion, and creator search 2026-02-21 23:53:16 -07:00
personal-briefing-beachhead.md feat: M0p1 runtime skeleton, M0p2 tooling & diagnostics, m1p4 signal ledger 2026-02-20 20:32:00 -07:00
README.md feat(m11): membership, snapshot install, and reseed (m11p5) 2026-06-12 19:55:54 -06:00
roadmap-to-cluster.md feat(m11): sharding × replication + rebalancing (m11p6 L3-L5) 2026-06-13 18:23:43 -06:00

tidalDB Engineering Docs

The engineering documentation home. Top-level product docs (VISION, USE_CASES, SEQUENCE, ARCHITECTURE, API, QUICKSTART, CODING_GUIDELINES, thoughts) live at the repository root; everything below is the deeper engineering record.

This and the repo root are the two canonical doc homes. There is intentionally no per-crate doc mirror (no tidal/docs/). Edit the canonical file, never a copy.

Component specs — specs/

The authoritative component specifications (status: Implemented, M0M8).

# Spec # Spec
00 Architecture overview 08 Query engine
01 Storage engine 09 Ranking & scoring
02 Entity model 10 Feedback loop
03 Signal system 11 Schema
04 Relationships 12 Cold start
05 Cohorts 13 Concurrency
06 Text retrieval 14 Scale architecture
07 Vector retrieval

Planning — planning/

Code reviews — reviews/

Guides — guides/

Task-oriented, build-an-app docs (complements the root QUICKSTART.md and API.md):

Operations — ops/ and runbooks/

Research — research/

ANN (1, 2) · Tantivy (1, 2) · Signal ledger (1, 2) · WAL · Type system · Tooling & diagnostics · Enterprise-readiness risks

Profiling — profiling/

Hotspot analysis · Scale baselines · Signal memory · Signal rollup eval · Social scale · Tantivy merge tuning · USearch tuning

Strategy

Content strategy · Personal-briefing beachhead