Since 15:00 UTC on 5 October every paired benchmark run that was not
superseded has hit its 25-minute step timeout. Each step runs ten base
and ten candidate samples, so per-sample growth is multiplied by twenty.
BenchmarkRegistryProjectionSnapshot (#2518) rebuilt a registry behind
StopTimer on every cold iteration. Go sizes b.N from timed work only, so
the empty-registry cases ran hundreds of thousands of untimed ingests
and took 16 s of a 100 ms benchtime. With #2486's new owner-index and
metadata benchmarks, internal/unifiedresources went from 8 s to 38 s per
sample. Cold now invalidates the registry's derived state instead. The
refresh never reads its own output, so this repeats a fresh ingest's
first read with the same allocations, and the family drops from 22 s to
about 5 s per sample.
Paired runs also measured every package even when both trees compiled
identical code, as on frontend-only changes. They now sample only
packages whose in-module dependency closure the change reaches. Module
files, dirty or non-Git trees and an unreadable graph still select
everything.
A module or shared-model change still samples nearly every package,
about 24 minutes with warm-up. The step therefore gets a measured 30
minutes, and the script stops at a 28-minute projected budget with
per-package costs instead of meeting a bare timeout.
rcourtman
b027bb0e8e