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From: Adam David <adam@veda.is>
Message-Id: <199610072322.XAA06650@veda.is>
Subject: Re: cvs commit:  src/sys/vm vm_page.h
To: dyson@freebsd.org
Date: Mon, 7 Oct 1996 23:22:11 +0000 (GMT)
Cc: guido@gvr.win.tue.nl, dyson@freebsd.org, dyson@freefall.freebsd.org,
        CVS-committers@freefall.freebsd.org, cvs-all@freefall.freebsd.org,
        cvs-sys@freefall.freebsd.org
In-Reply-To: <199610072234.RAA03072@dyson.iquest.net> from "John S. Dyson" at "Oct 7, 96 05:34:26 pm"
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> > > > Perhaps we could introduce a new word in the kernel config file.
> > > > Something like 
> > > > cache	<n>
> > > > where <n> is the amount of L2 cache. The L1 cache is processor specific
> > > > and thus can be obtained via the  cpu directive. The rest can then be
> > > > doen with macros.
> > > >
> > > Actually, the L1 cache will be changing on P5 class machines soon.
> > 
> > hmm. But that would be identifiable by the stepping number, right?

> In the longer term (probably in release timeframe) an attempt to probe
> the system interface chips would be useful, upon failure, perhaps
> default to 256K.  (Most reasonably high perf systems since the
> 386 and certainly the 486 have 256K (maybe some 128K) cache.)  It
> is only the medium 386s that had 64K anyway.

... and Cx486-DLC
Also some systems might be supplied without L2 cache altogether, or the cache
misconfigured so it is equivalent to non-existence.

Is there no reliable probe for cache size that could be coaxed to work on
all systems?

==
Adam