From owner-freebsd-fs@FreeBSD.ORG  Mon Jan 10 10:11:46 2005
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To: Barath S <barath_yes@yahoo.com.sg>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 10 Jan 2005 18:08:40 +0800."
             <20050110100840.29845.qmail@web30301.mail.mud.yahoo.com> 
Date: Mon, 10 Jan 2005 11:11:44 +0100
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cc: FreeBsd-MailGrp <freebsd-fs@freebsd.org>
cc: Scott Long <scottl@freebsd.org>
Subject: Re: using mfs of size > 64Mb and system stability 
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In message <20050110100840.29845.qmail@web30301.mail.mud.yahoo.com>, Barath S w
rites:
>Initially, I didn't go for swap based fs as I felt
>that  the memory occupied will be from the swap area.
>As you are saying that the allocation will be from
>buffer/cache, I will test swap-mfs.

malloc backing should not be used for large disks.

If you _truly_ want to have a large disk which is memory backed,
you should consider using the "preload" backing as this will withdraw
the memory entirely from the kernels use.

In general, the benefit from using RAM disks is much smaller than
most people realize.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.