chellomere@lemmy.worldtoTechnology@lemmy.world•FFmpeg devs boast of up to 94x performance boost after implementing handwritten AVX-512 assembly codeEnglish
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18 days agoYeah 7000-series Ryzen benefits from the avx512 code paths in ffmpeg. I’ve benchmarked a 5900x vs a 7900x specifically for software H.265 decoding and there was a sizeable difference.
This is great, but the context is that this is for specific inner loops, and it is compared to the C version of that specific inner loop. Typically what was used before this on a computer with avx512 was the avx2 version of the inner loop, and the speedup compared to that version appears to be up to 60%: https://x.com/FFmpeg/status/1852542388851601913 . Then as not a specific inner loop isn’t run all the time, the speedup is probably much less than 60%. This is still sizeable, but the actual speedup in practice with this implementation is far far from 94x.