From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Sanders <jeremy@jeremysanders.net>
Subject: Re: Btrfs slowdown
Date: Mon, 25 Jul 2011 15:37:51 +0100
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Cc: ceph-devel@vger.kernel.org
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Christian Brunner wrote:

> we are running a ceph cluster with btrfs as it's base filesystem
> (kernel 3.0). At the beginning everything worked very well, but after
> a few days (2-3) things are getting very slow.

We get quite a slowdown over time, doing rsyncs to different snapshots. 
Btrfs seems to go from using several threads in parallel btrfs-endio-0,1,2, 
shown in top, to just using a single thread btrfs-delalloc.

Jeremy