🚀 go-pugleaf

In article <14362@amdcad.UUCP> phil@amdcad.UUCP (Phil Ngai) writes:
>...does seem to be the case that the Unix kernel does not interact with
>caches as well as applications such as nroff. This led me to wonder if
>in that case, one might not do well to turn off the cache while the
>processor is in supervisor mode, since the hit rate does not seem to
>be very high and you thereby avoid flushing the cache of information
>that is useful to the application....

1) There ARE places in teh kernel that are worth selective uncaching.
2) In general, uncaching the kernel is probably not the thing to do,
although this may vary according to cache design, applications, etc.
In particular, as caches continue to increase in size, kernel cache
residence in a multi-process environment incerases substantially.
Some modest evidence:
	a) There's been some interesting recent research on the area
	at Stanford.
	b) We've experimented a lot at MIPS, especially early, with
	uncached kernels; we also changed I-cache sizes at one point.
	The results [I can't give you the details] : our kernels run cached.
-- 
-john mashey	DISCLAIMER: <generic disclaimer, I speak for me only, etc>
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