I'm going to retract my support for this - I just profiled a scenario where I generate geometry on the CPU every frame, upload it via a copy queue, then have the gfx queue do clears + some work before waiting for same-frame copy.

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• URL: https://x.com/SheriefFYI/status/1738800602568638492
• Author: Sherief, FYI (@SheriefFYI)
• Posted: 2023-12-24 05:55:43

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1/ @SheriefFYI

I’m going to retract my support for this - I just profiled a scenario where I generate geometry on the CPU every frame, upload it via a copy queue, then have the gfx queue do clears + some work before waiting for same-frame copy. Delay is ~50us from signal to gfx queue resuming.

Branches: 2023-12-24-lectem-sorry-i-didnt-have-time-to-do-this-during-the, 2023-12-24-NOTimothyLottes-2x-faster-today-perhaps-prior-on-amd-i-had-rgp

2/ @SheriefFYI

I profiled this in multiple cases - vsync on and frame taking < 16ms the wait is longer but that’s because other parts of the system clock down, so you still hit your vsync window. At no point was this cross-queue wait a significant cause of delay / missing frame time.

3/ @SheriefFYI

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