Re: Minutes from Feb 21 LSE Call

Alan Cox
2003-02-23T22:45:56Z

On Sun, 2003-02-23 at 20:50, Martin J. Bligh wrote:
> >> And the baroque instruction encoding on the x86 is actually a _good_
> >> thing: it's a rather dense encoding, which means that you win on icache.
> >> It's a bit hard to decode, but who cares? Existing chips do well at
> >> decoding, and thanks to the icache win they tend to perform better - and
> >> they load faster too (which is important - you can make your CPU have
> >> big caches, but _nothing_ saves you from the cold-cache costs).
> >
> > Next step: hardware gzip ?
>
> They did that already ... IBM were demonstrating such a thing a couple of
> years ago. Don't see it helping with icache though, as it unpacks between
> memory and the processory, IIRC.

I saw the L2/L3 compressed cache thing, and I thought "doh!", and I watched and
I've not seen it for a long time. What happened to it ?