Under CPU starvation (16 burners on 8 logical CPUs), all 5 rounds failed
at iteration 0 or 1 with "256 of 256 pollers returned before the close
began, so they were never in the race". The fixture contradicted itself:
the asserts-on settle waits up to 30s (plus a 50ms remainder) for every
poller to be counted inside the library, but each poller's own
next_event wait used a 5s timeout, so the first pollers timed out for
real while the settle was still waiting on the last ones. The race never
ran; the fixture just gave up on itself.
kPollTimeoutMs is now derived from the settle budget it must outlast in
every build configuration (asserts-on's counted deadline plus its fixed
remainder, and the no-seam #else's longer fixed window), named side by
side so they cannot drift apart again. A long poll timeout costs nothing
on a passing run, since the close is what actually ends each wait.
Also give the fixture's own failure to settle a distinct report. If
counted_deadline expires before every poller is counted, CloseRaceOnce
now says "fixture could not settle: N of M pollers counted inside after
30000 ms" instead of proceeding to a close that blames the pollers for a
race the fixture never set up.
holdclose, latecall and holdtimeout use the same counted-deadline idiom
but are not the same defect: their pollers are parked behind
cultmesh_quic_debug_hold_calls, so they cannot time out for real while
the settle waits, and were left alone.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
44ab3767ce