Ampere Altra Max 16MB LLC with 128 cores

By: Andrei F (andrei.delete@this.anandtech.com), May 25, 2021 8:06 am
Room: Moderated Discussions
Doug S (foo.delete@this.bar.bar) on May 25, 2021 7:50 am wrote:
> Ganon (anon.delete@this.gmail.com) on May 25, 2021 1:30 am wrote:
> > https://amperecomputing.com/wp-content/uploads/2021/05/Altra_Max_PB_v0.55_20210514.pdf
> >
> > 128 cores with 16MB seems small; esp when compared to what amd rome/milan is providing. Obviously
> > this is targeting only certain workloads (minimal sharing/small per thread working set).
> >
> > Any thoughts?
>
>
> The biggest thing that jumped out at me when I read about it was going from 32MB to 16MB SLC.
> Did they sacrifice cache area to add more cores? They only gained 32% increased performance from
> 60% more cores in SPECrate 2017_int_base which is as embarrassingly parallel as workloads can
> get, so clearly they are running into some not insignificant scaling issues. If the issue is
> maxing out memory bandwidth, why not add more memory controllers or go with DDR5 this time?

SPEC is still very memory and cache-bound in the geomean score.

Given Ampere's announcement of their new custom cores and hyper-focus on cloud workloads it seems very clear that they're targeting only workloads that are important to their customers, which don't seem to be memory or cache-bound.

We saw the same kind of two sides to the 80C Altra, in that it dominates anything execution throughput bound but less so anything memory.

https://images.anandtech.com/graphs/graph16594/117494.png
< Previous Post in ThreadNext Post in Thread >
TopicPosted ByDate
Ampere Altra Max 16MB LLC with 128 coresGanon2021/05/25 01:30 AM
  Ampere Altra Max 16MB LLC with 128 coresanon2021/05/25 03:11 AM
    Ampere Altra Max 16MB LLC with 128 coresHeikki Kultala2021/05/25 11:22 PM
      Ampere Altra Max 16MB LLC with 128 coresAnon2021/05/26 01:36 PM
        Ampere Altra Max 16MB LLC with 128 coresChester2021/05/26 02:54 PM
          Ampere Altra Max 16MB LLC with 128 coresChester2021/05/26 03:03 PM
  Ampere Altra Max 16MB LLC with 128 coresDoug S2021/05/25 07:50 AM
    Ampere Altra Max 16MB LLC with 128 coresAndrei F2021/05/25 08:06 AM
    Ampere Altra Max 16MB LLC with 128 coresRayla2021/05/25 08:17 AM
  A few thoughts on Ampere's Altra MaxPaul A. Clayton2021/05/27 12:00 PM
    A few thoughts on Ampere's Altra MaxBjörn Ragnar Björnsson2021/05/27 03:47 PM
      Yeah, I should have looked for and through a data sheet (NT)Paul A. Clayton2021/05/27 06:25 PM
    A few thoughts on Ampere's Altra MaxAdrian2021/05/27 11:13 PM
      Boring can be profitablePaul A. Clayton2021/05/29 12:18 PM
Reply to this Topic
Name:
Email:
Topic:
Body: No Text
How do you spell tangerine? 🍊