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From: dawes@suphys.physics.su.OZ.AU (David Dawes)
Newsgroups: comp.unix.sysv386
Subject: Re: File system performance
Message-ID: <1990Nov18.125156.24118@metro.ucc.su.OZ.AU>
Date: 18 Nov 90 12:51:56 GMT
References: <294@audfax.audiofax.com> <1990Nov3.124110.2155@metro.ucc.su.OZ.AU> <1305@bilver.UUCP>
Reply-To: dawes@suphys.physics.su.OZ.AU (David Dawes)
Organization: School of Physics, Uni of Sydney, Australia.
Lines: 29
Nntp-Posting-Host: suphys.physics.su.oz.au

In article <1305@bilver.UUCP> bill@bilver.UUCP (Bill Vermillion) writes:
>In article <1990Nov3.124110.2155@metro.ucc.su.OZ.AU> dawes@suphys.physics.su.OZ.AU (David Dawes) writes:
>
>>I too am using ESIX rev D with ffs.  One of my file systems became heavily
>>fragmented, and got to the point where there were 0 free blocks, and
>>5000 free frags.  df reported 10000 blocks free, but attempting to write
>>to the file system resulted in "Disk full" errors.  This meant that I
>>had an unusable 5MB on a 65MB file system. (BTW, there were plenty of free
>>inodes.)
> 
>>Is this how FFS is supposed to work, or is there a problem with the ESIX
>>implementation?
>
>That's about the right amount.  Check your manual in the newfs entry or the
>ffsmkfs entry, and you will see that 10% of the disk is reserved and can
>NOT be used by anyone except the super user.  That disk is full 0%, as far
>as a regular user is concerned.

I forgot to mention that I checked this angle, and found that it wasn't the
problem.  I've not seen any evidence that the min-free parameter actually
does anything on an Esix FFS.  My problem was that there were just too many
frags.  I have been able to improve this by using 4k blocks (with 1k frags).

David
--
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 David Dawes (dawes@suphys.physics.su.oz.au) DoD#210   | Phone: +612 692 2639
 School of Physics, University of Sydney, Australia    | Fax:   +612 660 2903
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