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From: John Dyson <dyson@dyson.iquest.net>
Message-Id: <199610072028.PAA02845@dyson.iquest.net>
Subject: Re: cvs commit:  src/sys/vm vm_page.h
To: guido@gvr.win.tue.nl (Guido van Rooij)
Date: Mon, 7 Oct 1996 15:28:02 -0500 (EST)
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        CVS-committers@freefall.freebsd.org, cvs-all@freefall.freebsd.org,
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In-Reply-To: <199610072008.WAA14802@gvr.win.tue.nl> from "Guido van Rooij" at Oct 7, 96 10:08:36 pm
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> John Dyson wrote:
> > > 
> > PQ_L2_SIZE is the size in pages...  PQ_L2_SIZE * PAGE_SIZE = 256k.
> > IMO, It is kind-of bogus to "hard-code" the value, and I am thinking about
> > a good solution for that problem.  The value is controllable from the
> > config file, but my naming conventions leave something to be desired,
> > so I haven't documented them (yet.)  If you have any ideas, let me know!!!
> > 
> 
> 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.

> Btw: Isn't it possible to somehow get the amount of cache at boottime?
> 
It is possible (I think) on a pci-chipset specific basis.  We could
also estimate it like 'lat_mem_rd', but that would be going too far,
probably.

John