live sync
docs/guides/live-sync.md
Live Sync: Keep the Index Current
Goal
Every markdown change in the brain repo is searchable within minutes, automatically, with no manual intervention.
What the User Gets
Without this: you correct a hallucination in a brain page, but the vector DB
keeps serving the old text because nobody ran gbrain sync. Stale search
results erode trust. The brain becomes unreliable.
With this: edits show up in search within minutes. The vector DB stays current with the brain repo automatically. You never have to remember to run sync.
Implementation
Prerequisite: a reachable direct connection
GBrain is tuned for the Supabase Transaction pooler (port 6543): it
auto-disables prepared statements there and routes engine.transaction()
(migrations, DDL, sync imports) to a derived direct connection
(db.<ref>.supabase.co:5432). That direct host is IPv6-only, so on an
IPv4-only host it is unreachable. When that happens gbrain now falls back to
the pooler automatically (one stderr warning, then single-pool mode for the
rest of the process) — but the pooler's ~2-min statement timeout can truncate
very long migrations or bulk imports.
Fix: make the direct connection reachable over IPv4. Either set
GBRAIN_DIRECT_DATABASE_URL to the Session pooler string (port 5432 on the
pooler.supabase.com host, IPv4), or enable Supabase's IPv4 add-on.
GBRAIN_DISABLE_DIRECT_POOL=1 skips the direct pool (and the fallback warning)
entirely. Verify by running gbrain sync and checking that the page count in
gbrain stats matches the syncable file count in the repo.
The Primitives
Always chain sync + embed:
gbrain sync --repo /path/to/brain && gbrain embed --stale
gbrain sync --repo <path>-- one-shot incremental sync. Detects changes viagit diff, imports only what changed. For small changesets (<= 100 files), embeddings are generated inline during import — unless the inline cost gate intervenes: when the estimated embedding spend crosses the configured floor in a non-interactive session (cron,--json), sync auto-defers embeds to a cappedembed-backfilljob instead of spending silently. Either way the chunks get embedded; a deferred run just finishes asynchronously. See spend controls.gbrain embed --stale-- backfill embeddings for any chunks that don't have them. Safety net for large syncs (>100 files) or prior--no-embedruns. On a keyless brain (installed with--no-embedding), a bare stale embed refuses cleanly — exit 0 with a stderr note — so this chain is safe to schedule on keyless installs; keyword search keeps working. Explicit embed requests (a slug,--slugs,--all) still exit 1 on a keyless brain.gbrain sync --watch --repo <path>-- foreground polling loop, every 60s (configurable with--interval N). Embeds inline for small changesets. Exits after 5 consecutive failures, so run under a process manager or pair with a cron fallback.
Approach 1: Cron Job (recommended)
Run every 5-30 minutes. Works with any cron scheduler.
gbrain sync --repo /data/brain && gbrain embed --stale
OpenClaw:
Name: gbrain-auto-sync
Schedule: */15 * * * *
Prompt: "Run: gbrain sync --repo /data/brain && gbrain embed --stale
Log the result. If sync errors mention an unreachable host or timeout,
the direct connection isn't reachable over IPv4 (set
GBRAIN_DIRECT_DATABASE_URL to the Session pooler, or enable the IPv4 add-on)."
Hermes:
/cron add "*/15 * * * *" "Run gbrain sync --repo /data/brain &&
gbrain embed --stale. Log the result." --name "gbrain-auto-sync"
Approach 2: Long-Lived Watcher
For near-instant sync (60s polling). Run under a process manager that
auto-restarts on exit. Pair with a cron fallback since --watch exits
on repeated failures.
gbrain sync --watch --repo /data/brain
Approach 3: Git Hook / Webhook
Triggers sync on push events for instant sync (<5s).
- GitHub webhook: Set up the webhook to call
gbrain sync --repo /data/brain && gbrain embed --stale. VerifyX-Hub-Signature-256against a shared secret. - Git post-receive hook: If the brain repo is on the same machine.
What Gets Synced
Sync only indexes "syncable" markdown files. These are excluded by design:
- Hidden paths (
.git/,.raw/, etc.) and vendored/generated trees (node_modules/,dist/,build/,venv/) - Meta files:
README.md,index.md,schema.md,log.md,RESOLVER.md
Everything else is ordinary synced content — including ops/ (the bundled
daily-task-manager skill files its canonical page under ops/tasks).
Sync is Idempotent — and Resumable
Concurrent runs are safe. Two syncs on the same commit no-op because content
hashes match. If both a cron and --watch fire simultaneously, no conflict.
Long syncs also survive being killed: progress checkpoints into the database
as files drain, so a killed or aborted run resumes from where it stopped, and
the sync bookmark only advances on true completion. A progress-aware stall
watchdog (GBRAIN_SYNC_STALL_ABORT_SECONDS, default 900, 0 disables) aborts
a run that stops making forward progress and releases the per-source lock so
the next gbrain sync picks up from the checkpoint. The checkpoint cadence
and lock-steal grace are tunable via GBRAIN_SYNC_* / GBRAIN_LOCK_* env
vars — incident-time escape hatches, not everyday knobs.
Tricky Spots
-
Always chain sync + embed. Running
gbrain syncwithoutgbrain embed --staleleaves new chunks without embeddings. They exist in the database but are invisible to vector search. Always run both commands together. The&&ensures embed only runs if sync succeeds. -
--watch polls, it doesn't stream. The
--watchflag polls every 60s (configurable). It is not a filesystem watcher or git hook. It exits after 5 consecutive failures, so it needs a process manager (systemd, pm2) or a cron fallback to stay alive. Don't assume it runs forever. -
Webhook needs the server running. If you use a GitHub webhook for instant sync, the receiving server must be running and reachable. If the server is down when a push happens, that sync is missed. Pair webhooks with a cron fallback that catches anything the webhook missed.
-
A single un-parseable file can't wedge all indexing. When a file fails to import (malformed YAML frontmatter, an unquoted colon, etc.), sync holds the bookmark and tells you exactly which file broke — a fresh failure fails closed so nothing is silently dropped. But a file that fails the same way
GBRAIN_SYNC_AUTOSKIP_AFTERconsecutive syncs (default 3, set0to disable) is auto-skipped so the rest of the brain keeps indexing past it. Skipped files don't disappear:gbrain doctorkeeps warning until you fix or delete them, and fixing the file clears it on the next sync. A repository history rewrite still hard-blocks even with--skip-failed. Rungbrain sync --skip-failedto acknowledge a known-bad set yourself. -
Staleness can't read "fresh" forever. A source whose content stopped moving (or whose local clone vanished) used to report fresh indefinitely off the stored content timestamp. Content-relative staleness now ramps toward stale once wall-clock time since the last sync passes a ceiling (default 72h;
GBRAIN_STALENESS_CEILING_HOURSto tune — it tracksGBRAIN_SYNC_FRESHNESS_FAIL_HOURSunless set). The ramp is gradual, so the warn tier still fires before the fail tier.gbrain statussource rows carryhours_since_last_sync(raw wall-clock truth) alongside the threshold-relativestaleness_hoursthat drives the fresh/stale class. -
Import checkpoints name the import target, not the caller's CWD. Interrupted
gbrain import <dir>runs may leave~/.gbrain/import-checkpoint.jsonso the next import can resume. The checkpointdiris the absolute, resolved import target captured when import starts. It is not a cleanup instruction and it must not be re-derived from the process working directory. Checkpoints written by gbrain includeschema_version: 1,owner: "gbrain", andkind: "import"so downstream tools can validate the contract before deciding whether to resume.
How to Verify
-
Edit a file and search for the change. Edit a brain markdown file, commit, and push. Wait for the next sync cycle (cron interval or
--watchpoll). Rungbrain search "<text from the edit>". The updated content should appear in results. If it returns old content, sync failed. -
Compare page count to file count. Run
gbrain statsand count the syncable markdown files in the brain repo. The page count in the database should match. If they diverge, files are being silently skipped (likely an unreachable direct connection on IPv4 — see the prerequisite above). -
Check embedded chunk count. In
gbrain stats, the embedded chunk count should be close to the total chunk count. A large gap meansgbrain embed --staleisn't running after sync, leaving chunks invisible to vector search. -
Gate on the daemon's heartbeat. If the built-in daemon runs your sync (
gbrain autopilot --install), wire your scheduler's health check togbrain autopilot --status. The exit code is the signal: 0 fresh (or nothing installed), 1 needs attention (stale heartbeat, never ran, or paused by a migration), 2 the daemon took itself out of rotation.--jsonemits the full report, includingheartbeat_age_seconds. Status reads only the filesystem — no database connection — so it keeps working during the exact outages it exists to diagnose.
Part of the GBrain Skillpack.