Subject: Re: mfs woes
To: Andrew Brown <>
From: Steven M. Bellovin <>
List: tech-kern
Date: 07/13/2004 23:32:22
In message <>, Andrew Brown writes:
>On Tue, Jul 13, 2004 at 11:17:20PM -0400, Steven M. Bellovin wrote:
>>In message <>, Andrew Brown writes:
>>>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.
>>Given the new buffer cache architecture, I've been wondering if mfs 
>>even makes sense these days.  Perhaps a disk partition mounted with 
>>async would provide comparable performance?  I don't know; I haven't 
>>tried it.  But I'm getting ready to bring up a new machine; I might 
>>reserve a partition and see what happens.
>mfs still makes sense as a "simple place to keep transient files that
>you don't need from one boot to the next".  newfs'ing or rmrf'ing /tmp
>doesn't count, imho, because it doesn't scale.

I suspect that newfs does scale quite well to the size file system that 
MFS can handle.

		--Steve Bellovin,