Slower here.
Using LGHs build with a dell 2u rack server with a Xeon Gold 6126 (12c/24t). CPU utilization dropped with about 10% (both for 1080p and 2160p) and clockspeed dropped from 2.9Ghz to 2.4Ghz. I'm guessing that the gains for AVX512 didnt outweight the dropp in clockspeed and utilization.
Tears of steal source (10bit UHD-Bluray compat x265 source for 2160p test, 8bit bluray compat x264 soruce for 1080p)
2160p with avx512: 80-90% CPU usage, 2.28 fps
Code:
--asm avx512 --preset slow --profile main10 --level-idc 51 --crf 22
2160p: 100% CPU usage, 2.36 fps
Code:
--preset slow --profile main10 --level-idc 51 --crf 22
1080p with avx512: 45-55% CPU usage, 6.54 fps
Code:
--asm avx512 --preset slow --profile main10 --level-idc 41 --crf 18
1080p: 55-65% CPU usage, 7.14 fps
Code:
--preset slow --profile main10 --level-idc 41 --crf 18