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From: "John S. Dyson" <toor@dyson.iquest.net>
Message-Id: <199604150122.UAA00309@dyson.iquest.net>
Subject: Re: Unices are created equal, but ...
To: davidg@Root.COM
Date: Sun, 14 Apr 1996 20:22:16 -0500 (EST)
Cc: dyson@FreeBSD.org, andreas@knobel.gun.de, joerg_wunsch@uriah.heep.sax.de,
        groudier@iplus.fr, hackers@FreeBSD.org, linux-kernel@vger.rutgers.edu
In-Reply-To: <199604142355.QAA04357@Root.COM> from "David Greenman" at Apr 14, 96 04:55:34 pm
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> >systems!!!  The AT&T GIS/NCR/Tandem boxes really acted badly when users
> >would tune the system to allow too much memory to be dirty filesystem
> >cache buffers.  I could be convinced that 1/4 of memory for dirty buffers
> >is okay, and in some cases even more could be considered.  But those cases
> >where a system could gain significantly from huge write caches are few
> >and far between.  I guess if managed VERY WELL, a large (>1/2 mem) write cache
> >would be good -- I just haven't seen that yet.
> 
>    Worst case, that would be about 256MB of cached data to write out on
> wcarchive. :-) I think I prefer the current scheme. :-)
> 
> -DG
> 
That is the point -- those boxes did have 256MBytes!!!  Imagine what sync
did to the systems!!!

John