[PragmaticPulp]

This was massively exaggerated by journalists when AVX-512 was first announced.

It is true that randomly applied AVX-512 instructions can cause a slight clock speed reduction, the proper way to use libraries like this would be within specific hot code loops where the mild clock speed reduction is more than offset by the huge parallelism increase.

This doesn’t make sense if you’re a consumer doing something multitasking and a background process is invoking the AVX-512 penalty in the background, but it usually would make sense in a server scenario.

[adgjlsfhk1]

the thing I never understood about this is why Intel didn't just add latency to the avx512 instructions instead? that seems much easier than downclocking the whole cpu

[janwas]

I believe they do actually do something like this - until power and voltage delivery change, wide instructions are throttled independently of frequency changes (which on SKX involved a short halt).