Documents the four perf surfaces shipped in Phase 6:
- Tracing surface (PR 6.1) — table of every span the driver emits +
rationale for stream-level (not per-event) coverage.
- Metrics surface (PR 6.2) — three EventPump counters, tagging
scheme, the bounded-channel design, and the
received = dispatched + dropped + in-flight invariant.
- Buffered update interval (PR 6.3) — how MxAccess.PublishingIntervalMs
flows through both subscribe paths and what's still pending on the
gw side (typed SetBufferedUpdateInterval helper).
- Soak scenario (PR 6.4) — env-var-gated 24h × 50k validation with
the CI-compressed override recipe.
- Tuned defaults (PR 6.5) — table of every default with source +
notes; rows marked "unchanged" carry the explicit "no live data
argues for changing this" caveat.
Closes with a "where to look first when something's slow" runbook
section so on-call doesn't have to re-derive the trace+metric
correlation map from primary docs.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>