Nothing in the workspace compared any number to 100,000 events/s while
the evidence file reported "AM-6 | met, 16.5x". Now a test does — a test,
not a bench, because Criterion reports throughput and asserts nothing,
which is why this row measured nothing for six passes.
Measured on bnt-lap001: 341,280 ev/s in debug (3.4x the target), ~2.4-3.1M
in release. The spec target holds even in an unoptimized build, so the
gate needs no cfg split and runs in the ordinary `make test`.
The trap this task named — loosening a flaky timing assertion until it
never fires — is avoided by construction. The threshold is the spec value,
untouched; the constant says lowering it requires an ADR; and the failure
message repeats that, states measured headroom, and names reference
figures, so an agent hitting a red AM-6 is told not to tune it in the
place they are actually reading. Robustness comes from best-of-N, not from
a lower bar: a throughput floor asks whether the machine is capable, so
transient load should not fail the build.
Two positive controls in the test: a run that applied fewer than 50,000
events, or measured zero elapsed time, fails rather than scoring as
infinite throughput.
Verified by a PROPERTY mutation — 4,000 black_box iterations injected into
GroundState::fold, the hot path — not a threshold tweak, which would only
prove the comparison runs.
And the FA class found last pass is now gated. mutation-check rows gained
an `expect` field: the mutant's output must contain the row's stated
failure string or the verdict is WRONG-REASON, not red. Without it a
mutation that merely failed to compile would credit its row with an
assertion it does not have. Verified by pointing expect at a string the
verifier never prints and watching the verdict flip. This is remedy (2)
from the CB-WP-0005 retrospective, built a task earlier than planned
because the class it guards is the newest and most dangerous.
M-D1-MUT: 4 -> 5 of 14.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
tegwick
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