Re: question about M2 "feature"

Mike Jagdis (mike@roan.co.uk)
Thu, 24 Jul 1997 08:56:23 +0100 (GMT/BST)


On Tue, 22 Jul 1997, Patrick St. Jean wrote:

> I saw it in "Windows Sources" August 1997 issue. Page 108 third column.
>
> here's the quote:
> [snip]
> An intersting feature available on the 6x86MX, which has yet to be
> implemented in software is Scratchpad RAM. This tiny 8K block of cache on
> the chip stores small pieces of code locally, rather than in the L2 cache.
> Cyrix promises that this will allow a serious performance boost to any
> instructions an application might post there.
>
> end quote.

It isn't a special area of "scrathpad RAM". The 6x86MX allows you
to lock down L1 cache lines. This means that the line will never
be discard and hence you will never take a reload hit on the
region of memory it is covering. Of course, you also have one
less line of L1 cache available for general caching too...

Mike

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