T03 reported AM-5 at 87.0 s / 61.3 s and called it a 45% breach of the
60 s target. Re-measured with the fixed instrument on a quiet machine:
load before measuring: 0.14 per CPU over 8 CPUs — quiet
dev toolchain (default features) 37.3 s [ok target <= 60 s]
best of 3: 37.3, 42.9, 46.2 (spread 1.24x)
shipped runtime (--no-default-features) 41.2 s [ok target <= 60 s]
best of 3: 41.2, 50.8, 54.2 (spread 1.32x)
AM-5 is MET with 1.6x headroom. The 87.0 s was measured while the machine
was busy with mutation-check and cargo builds — a timing measurement under
contention measures the contention.
That is the same error class as AM-6's, committed two tasks later in the
same session by the same author, in the row immediately after the one
where it was diagnosed. Knowing the failure mode did not prevent it; only
building the guard did. That is the InnerLoop v1.2 design-goal argument
holding up under a third instance: optimize for cheap correction, because
prevention keeps not converging.
The instrument now refuses to measure above 0.5 load per CPU, takes the
best of 3, and warns when the spread exceeds 1.25x. Best, not worst: a
build-time ceiling asks whether the machine can do it in 60 s, the mirror
of AM-6's best-of-N for a throughput floor. The spread warning fired on
the shipped-runtime samples — consecutive clean builds degrade 37.3 ->
46.2 — so a quiet machine is not a uniform one either.
The escalation to a maintainer decision is withdrawn: there is no breach.
The build profiling done while the breach was believed real is recorded in
the log rather than acted on — 174 s of CPU work at only 3.2x parallelism
on 8 cores, a ~22 s serial proc-macro chain, lto=thin worth ~6 s, and
pinning ppv-lite86 to drop zerocopy making it worse (23 -> 25 crates).
With 1.6x headroom there is nothing to buy.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
loop-lint failed at 427 lines. Third workplan in this project to cross the
~400-line loadability limit, which makes it structural rather than a
formatting nuisance: delivery notes accumulate in a file whose job is to
state intent, and every remaining task would push it further over.
history/260801-cb-wp-0006-log.md now holds the per-task narrative; the
workplan keeps a one-line pointer per task. 427 -> 270 lines, with room
for T05-T09. T08 draws on both.
Same fix shape as CB-WP-0005, where the limit exposed a circular reference
rather than mere length. A gate that keeps finding real structure is worth
more than its stated rule.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
