* fix(agent-history): keep the app responsive while scanning huge OpenCode databases (#8864)
Opening or refreshing Agent Session History froze the entire app when
OpenCode's opencode.db had grown to multiple GB (reporter: 29 GB with
20+ live opencode writers). All OpenCode SQLite reads ran synchronously
(node:sqlite DatabaseSync) on the Electron main-process event loop, the
discovery query evaluated a COUNT+json_extract subquery for every
session before LIMIT, and the preview query JSON-parsed every part blob
of each session. Live writers bump session.time_updated continuously,
so the mtime parse cache missed every 15s/focus/manual refresh and the
multi-tens-of-seconds freeze repeated forever.
Fix:
- Run OpenCode SQLite discovery and per-session parsing on a persistent
worker thread (lazy spawn, unref'd, idle teardown, FIFO dispatch,
per-call timeouts, crash-loop cap). Faults surface as per-source scan
issues instead of stalls; other providers' results always arrive.
- Fall back to the in-process reader when no worker bundle exists,
surfacing a degraded-mode scan issue so a persistent fallback cannot
silently reintroduce the hang.
- Bound the queries: sort+LIMIT sessions before computing message
counts, and source previews from the newest 100 messages via the
(session_id, time_created, id) index instead of scanning every part.
Measured on a 22 GB synthetic DB matching the reporter's shape: main-
process IPC RTT during a fully cache-invalidated scan went from a
32.8 s continuous block (UI click timeout) to 1 ms max, with the panel
populating normally (previews and message counts intact).
* fix(agent-history): drop the cached worker handle after a clean exit and document worker-client exports
A worker that exits cleanly on its own left this.worker pointing at the dead
thread; the next request would post into it and stall to its timeout instead
of respawning. Clean idle exits now drop the handle without counting as a
death. Also adds JSDoc to the new exported scan-worker surfaces.
* fix(agent-history): keep OpenCode scans off the main thread
* fix(agent-history): align OpenCode recency ordering
NeilandOrca
Brennan Benson