Ungo (a.delete@this.b.c.d.e) on May 23, 2022 1:27 am wrote:
> Jan Wassenberg (jan.wassenberg.delete@this.gmail.com) on May 22, 2022 11:11 pm wrote:
> > But given that we are moving into a world with more
> > heterogeneity (whether we like it or not), isn't that an occasion to perhaps adapt what we've been doing?
>
> Who says we're moving into a world with more ISA-level heterogeneity in general purpose
> personal computers? Performance and efficiency heterogeneity is clearly here to stay,

Hopefully, not, at least for desktops and 13+'' laptops.

> but in application processor cores, ISA heterogeneity doesn't seem to have a future.
>
> Consider that Alder Lake's ISA heterogeneity proved to be such a problem that Intel decided to patch
> out a huge chunk of it by disabling AVX512 in AL's P cores. Doesn't that tell you something?
>
> So I don't see AL as a trendsetter. I think it's something unique to Intel's current circumstances.
> A few years ago, Intel must have realized they needed a high performance heterogenous chip yesterday,
> and the fastest path to get one to market was to repurpose an Atom core as an E core. If Intel
> is being run well, in the near future they should begin shipping heterogenous chips whose cores
> are far better matched to each other than Gracemont and Golden Cove.
>
> It's not just x86 either, there have been a few painful object lessons in the Arm space too.
> Today's standard practice is to pair Arm cores with identical (or nearly so) ISA features.