Files
rippled/docs
Pratik Mankawde 8dd64d4dcd fix(telemetry): add second-scale spanmetrics histogram buckets
P95 of second-scale spans was a meaningless interpolation. The spanmetrics
histogram topped out at [.. 1s, 5s], so consensus.round (~3.9s) and
consensus.establish (~1.9s) all fell into one 1s-5s bucket and
histogram_quantile interpolated linearly across that 4s-wide gap — the
"Build vs Close" / "Ledger Close Duration" panels' P95 read ~4800ms purely
as an artifact (verified: sum/count avg = 3824ms). ledger.acquire was worse:
~17% of samples exceeded the 5s ceiling, so its p95/p99 were unmeasurable.

Add 2s, 3s, 4s (resolve the 1-5s pile-up) and 10s, 30s (give the
ledger.acquire catch-up tail a measurable home). All ten existing boundaries
are preserved and the list stays strictly ascending (the connector
binary-searches buckets and silently misbuckets otherwise). Pin unit=ms so a
future collector default-unit flip can't rename the metric to _seconds.

Buckets chosen from the live mainnet distribution, not guessed. Native
beast::insight histograms (ms-scale RPC/IO timers in Telemetry.cpp) are 100%
under 5s, so they keep the original buckets — this is collector-only.

Applies on collector restart (cumulative series reset once, handled by
rate()). Runbook and regression-threshold bucket notes updated to match.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-07-22 14:27:06 +01:00
..
2020-03-30 18:57:35 -04:00