Mark Roulo (nothanks.delete@this.xxx.com) on September 14, 2021 3:51 pm wrote:
> hobold (hobold.delete@this.vectorizer.org) on September 14, 2021 6:47 am wrote:
> > Heikki Kultala (heikki.kultala.delete@this.gmail.com) on September 13, 2021 7:33 am wrote:
> >
> > > There are no little cores in Alder Lake. There are mediun cores. And these
> > > medium cores gives twice the performance/area than the big cores.
> > >
> > > Now there is throughput performance worth 12 big cores, but area of only 10 big cores.
> > >
> > > The advantage would be even better if there was 16 instead of 8 of those medium cores.
> >
> > Why stop there? By that line of reasoning, one would want many different core sizes
> > from big to little. Say, core N has performance proportional to 0.9^N, silicon
> > area proportional to 0.8^N, and power consumption proportional to 0.75^N.
> >
> > This way, the fewer threads are running, the faster each
> > thread gets to run. And the more runnable threads there
> > are, the more efficient the cores are getting (both in terms of energy as well as silicon real estate).
> >
> > Punch line: total silicon area and power consumption of an infinite number of such
> > cores is finite. :-) But performance is finite, too. And yes, the extreme version
> > of this idea is a joke ... but what about three, four, five ... core sizes?
> >
> > One could always shrink and re-use previous generation cores, instead of having to re-design
> > every core type from scratch. Or one could use parameterized synthesizable cores and let core
> > proliferation be a semi-automatic thing. We do have AI now to handle the bulk of grunt work.
>
> Caches seem to have played out this way.
>
> The older microprocessors didn't have caches.
>
> The z15 had L1 (I and D), L2, L3 and L4 ...
>
> If one want to think of "memory hierarchy" rather than cache we have something like:

You missed two levels:
>

>
1. Registers

>
2. L1 cache

>
3. L2 cache

>
4. L3 cache

>
5. L4 cache (on z15 anyway)

>
6. DRAM



7. Compressed memory


8. Flash


>
9. Disk for paging (HDD or SSD)

>
10. Tape

>