Chasing "Minesweeper is laggy" ended somewhere else entirely. Press-to-paint is
29ms median at x11vnc's socket and 29ms through the sidecar relay, but 35-200ms+
in the browser — so every bit of the variance is added by the one hop between,
which is officer.
Officer answering a trivial 401 on /api/health: median 1ms, p90 2ms, max 490ms.
summarizeTranscript full-reads and JSON.parses an entire transcript to build a
session-list row; timed against the largest here (196 MB, 70,137 entries) that
is 323ms to read plus 541ms to parse — 864ms of blocked loop per call. It is
cached on mtime, and a LIVE session appends every few seconds, so the cache
misses exactly when the agent is busy.
Filed rather than fixed: it is a hot path shared by every surface, and the right
shape (incremental parse keyed on size, versus moving summaries off the request
path) is an architecture call. The file already contains the argument for the
incremental version — "Claude only ever appends".
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Officer-Session: f7a62308-0977-4cf4-aa29-c020853fd420
pastilhasandClaude Opus 5
73a9b0bf51