During #802 qualification on exact candidate core SHA 5B8EB7AA62C9B906863E46F2F0BE2B49EF68772A45AC04597D46B103BD918527, the disabled-preparation/inline single-1440p-capture control lost six Program packets and the same six recording identities. Raw artifacts: artifacts/cpu-source-final-821-capture-cpu0/pair-1-inline.* (120 measured seconds after fixed 15-second warmup, 1080p60 Program, buffer2, GPU_CAPTURE=0).
The six measured misses were three pairs. At slots1932,5676,7340 the matching front was still Preparing at its deadline. At each following deadline, that previous front was Ready and expired, still blocking the queue: front1932 at target1933, front5676 at target5677, front7340 at target7341. Initial submitted ages were 7.15/5.90/4.24 ms; follow-up ready ages were 16.71/16.25/16.08 ms. Shutdown-only empty-source misses occur afterward and are distinct from the measured losses.
Code audit: deliveryLoop retires an expired Ready front at the top of its loop, but when an in-flight preparation becomes Ready after its lost deadline, waitUntilPrecise's predicate only wakes for a Ready front matching the NEW target. The expired Ready front cannot satisfy that predicate. The loop reaches the next deadline and charges another underrun before re-entering retirement. This is a plausible miss-amplification mechanism, not attribution of the original late GPU completion. The preparation-enabled counterpart passed; remaining controls continue.
Proposed focused repair: wake/re-enter retirement when the front becomes expired and Ready, without taking the next due slot early, waiting for optional exports or extending buffering. Add a deterministic real GPU preparation-delay/queue regression that fails before and recovers the following independently ready slot after repair. Preserve the first injected loss and counters; no claim that late content can be delivered on time. Validate subsequent identities, pixel ownership and original two-frame deadline mapping. Continue the current #802/#823 work; this finding is unranked until owner disposition.
During #802 qualification on exact candidate core SHA 5B8EB7AA62C9B906863E46F2F0BE2B49EF68772A45AC04597D46B103BD918527, the disabled-preparation/inline single-1440p-capture control lost six Program packets and the same six recording identities. Raw artifacts: artifacts/cpu-source-final-821-capture-cpu0/pair-1-inline.* (120 measured seconds after fixed 15-second warmup, 1080p60 Program, buffer2, GPU_CAPTURE=0).
The six measured misses were three pairs. At slots1932,5676,7340 the matching front was still Preparing at its deadline. At each following deadline, that previous front was Ready and expired, still blocking the queue: front1932 at target1933, front5676 at target5677, front7340 at target7341. Initial submitted ages were 7.15/5.90/4.24 ms; follow-up ready ages were 16.71/16.25/16.08 ms. Shutdown-only empty-source misses occur afterward and are distinct from the measured losses.
Code audit: deliveryLoop retires an expired Ready front at the top of its loop, but when an in-flight preparation becomes Ready after its lost deadline, waitUntilPrecise's predicate only wakes for a Ready front matching the NEW target. The expired Ready front cannot satisfy that predicate. The loop reaches the next deadline and charges another underrun before re-entering retirement. This is a plausible miss-amplification mechanism, not attribution of the original late GPU completion. The preparation-enabled counterpart passed; remaining controls continue.
Proposed focused repair: wake/re-enter retirement when the front becomes expired and Ready, without taking the next due slot early, waiting for optional exports or extending buffering. Add a deterministic real GPU preparation-delay/queue regression that fails before and recovers the following independently ready slot after repair. Preserve the first injected loss and counters; no claim that late content can be delivered on time. Validate subsequent identities, pixel ownership and original two-frame deadline mapping. Continue the current #802/#823 work; this finding is unranked until owner disposition.