Jukka Larja (roskakori2006.delete@this.gmail.com) on May 18, 2022 6:47 am wrote:
> me (me.delete@this.me.com) on May 18, 2022 5:50 am wrote:
> > > More likely, the opposite is going to happen in the next ten years: AVX512-less CPUs
> > > will rule the installed base and AVX512 will be, at best, HPC-only curiosity.
> > >
> > > 2021-2022 are peak years for AVx512 in terms of shipment and
> > > 2023 would be a peak year in terms of installed base.
> >
> > AVX-512 will be back on Intel's mainstream products. Eventually.
> > Especially since AMD is adding it in Zen 4.
>
> Just out of curiosity, has AMD said something official about
> this? I know there are rumours, but they go many ways.
>
> I'm not sure if Intel has said anything official, but I think there's a good reason to presume that
> next Core models (13th generation) to be released by the end of this year or early next year will
> still not have AVX-512 (due to efficiency cores not having it). By the 2024 who knows what makes
> sense and what not? Both Intel and AMD could decide that AVX-512 doesn't make sense in consumer
> products, or only makes sense as some heavily crippled, micro-coded compatibility thingy.


The timeline from designing in something like AVX512 to actually releasing CPUs that contain it isn't short. AMD could have made a decision to include AVX512 if at the time they felt it looked like Intel was going to introduce it across their whole line, or at least whole non-mobile line. Seeing them pull back later could cause them to 1) disable AVX512 functionality that exists in a core when it is released or 2) leave it enabled, but as with Intel include AVX512 in only some of their future cores.

So even if Zen 4 includes AVX512, I wouldn't take it as given that all future AMD cores will include it. Or that Intel would feel pressure to include AVX512 in all their cores even if AMD does go ahead and include it all of theirs.

I think it is too early to decide 2023 is the peak year for the installed base of AVX512, but it is way too early to say that AVX512 will exist AT ALL in any CPUs shipped five years from now. Maybe Intel has decided such long vectors are only useful in HPC. Maybe they are designing AVX1024 and intend a clear split between 1024 bit vectors in HPC and 256 bit vectors in everything else. Maybe they are designing a length agnostic successor similar to SVE2?

I don't think it makes sense for ANYONE to invest in AVX512 support for software because of some future assessment it will be table stakes - or even EXIST in the future. The only reason to make that investment is if it pays off TODAY, based on the installed base of AVX512 support in your target market TODAY.