Subject: Re: mfs woes
To: None <tech-kern@netbsd.org>
From: Andrew Brown <atatat@atatdot.net>
List: tech-kern
Date: 07/13/2004 23:01:12
On Tue, Jul 13, 2004 at 05:18:31PM -0500, David Young wrote:
>I am told that blocks in the memory filesystem (mfs) can end up in the
>buffer cache: this double-whammy on memory can lead to memory exhaustion.

yes, 'cause it's a "file system".

>The problem is compounded (I do not understand how or why) when multiple
>mfs are in use.
>
>Is there any bug-fix or work-around for the memory-inefficiency/exhaustion
>issue?  Can somebody outline what a fix would look like?

write a real swap-based file system?  mfs also comes with a ~2.9
gigabyte limit (on i386, at least).  when using USE_TOPDOWN_VM.  when
you're not, it comes with a ~1.8 gigabyte limit.  regardless of how
much ram or swap you have.

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