The GPU engine copies six small per-ring arrays back to the host every frame - the
clipped raw sum/sum2/count that the threshold is computed from, and the plain
corrected sum/sum2/count that become the azimuthal profile. They were plain
std::vectors, so the copies landed in pageable memory, and a device-to-host copy
into pageable memory blocks the calling thread until it has completed whatever
stream it was issued on. The profile snapshot sits between the plain pass and the
two sigma-clip passes, so Detect() stopped there and the device then sat idle while
the host caught up and enqueued the rest.
Register them, as AzIntEngineGPU already does with its own, and the copies are
genuinely asynchronous. Measured on a 4.5 Mpixel frame: 0.647 -> 0.621 ms per
frame. Nothing else changes - the spot list and the profile are unaffected.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
leonarski_fandClaude Opus 5
3ccb97e31b