Measuring the tracking-store queue on the rig moved nothing: the DB-done -> Notify.Send
gap stayed at 108 ms. The cost was the audit half of CachedCallTelemetryForwarder:
SqliteAuditWriter.WriteAsync enqueues synchronously but returns the BATCH completion,
and the writer loop coalesces for FlushIntervalMs (50 ms) before it commits, so each
awaited audit row cost ~50 ms + fsync and a cached call awaited three (submit,
attempted, resolve) on the script thread. Every other script-path emitter already
fired-and-observed; only this forwarder awaited.
TryEmitAuditAsync now hands the row to the writer and observes the completion on a
fault-logging continuation (the FallbackAuditWriter ring-buffer fallback still runs
inside that task). Best-effort contract unchanged; per-store FIFO unchanged; nothing
joins the audit and tracking stores by commit order.
Rig, FlowOutboundDemo, 5-run medians: inbound 194 -> 25 ms, site script run 176 -> 17 ms,
CachedWrite submit->done 61 -> 11 ms, DB done -> Notify.Send 108 -> 0.1 ms. The tracking
queue stays (three fewer fsyncs per call, batched). Docs corrected to attribute the cost
to the flush wait, with the trap recorded in CLAUDE.md and Component-SiteRuntime.md.
Tests: ForwardAsync returns while the audit commit is still pending (never-completing
writer task) and still records tracking; a late commit fault is swallowed.
Claude-Session: https://claude.ai/code/session_01NcMG6xXdsJbmD2wYAgkK29
Joseph Doherty
0ccbe140ae