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To: Joe Greco <jgreco@brasil.moneng.mei.com>
cc: hsu@cs.hut.fi, freebsd-current@FreeBSD.org
Subject: Re: mmap bugs gone yet? 
In-reply-to: Your message of "Fri, 14 Apr 95 17:36:32 CDT."
             <9504142236.AA02076@brasil.moneng.mei.com> 
From: David Greenman <davidg@Root.COM>
Reply-To: davidg@Root.COM
Date: Fri, 14 Apr 1995 19:14:17 -0700
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>> With the merged VM/buffer cache, i doubt it will buy too much to mmap
>> the files at all.
>
>This was not true on my Sun 3/60.  I never investigated to find out why,
>however.

   mmap should be faster at accessing files randomly and will eliminate an
extra copy compared with doing read() system calls. It might be slower when
modifying large amounts of large files. I think overall mmap would be faster,
but YYMV.

-DG