From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Clayton <andrew@digital-domain.net>
Subject: Re: RAID 5 performance issue.
Date: Wed, 3 Oct 2007 21:48:23 +0100
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To: David Rees <drees76@gmail.com>
Cc: Justin Piszcz <jpiszcz@lucidpixels.com>, Andrew Clayton <andrew@pccl.info>, linux-raid@vger.kernel.org
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On Wed, 3 Oct 2007 13:36:39 -0700, David Rees wrote:

> > # xfs_db -c frag -f /dev/md0
> > actual 1828276, ideal 1708782, fragmentation factor 6.54%
> >
> > Good or bad?
> 
> Not bad, but not that good, either. Try running xfs_fsr into a nightly
> cronjob. By default, it will defrag mounted xfs filesystems for up to
> 2 hours. Typically this is enough to keep fragmentation well below 1%.

Worth a shot.

> -Dave

Andrew