From owner-freebsd-hackers  Sat Jan  4 17:13:32 1997
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To: Charles Henrich <henrich@crh.cl.msu.edu>
cc: msmith@atrad.adelaide.edu.au (Michael Smith),
        joerg_wunsch@uriah.heep.sax.de, freebsd-hackers@FreeBSD.ORG
Subject: Re: MMAP Troubles (Joerg?) 
In-reply-to: Your message of "Sat, 04 Jan 1997 14:54:17 EST."
             <199701041954.OAA05981@crh.cl.msu.edu> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sat, 04 Jan 1997 17:12:27 -0800
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>> Slightly older news (but I suspect still current) was that INN is
>> faster on FreeBSD _without_ mmap, due to caching etc.  Remember that
>
>I dont see how that is, since the READ/WRITE's just turn into MMAP's inside the
>kernel (from what I understand of it).

   Pages that are read in using read have lower priority than mmaped pages
and can be more easily reclaimed. ...so it would probably be faster to do
read/write for articles, but slower to do read/write for the active file
(which you want to stay in memory if possible).

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project