From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefan Priebe <s.priebe@profihost.ag>
Subject: Re: poor OSD performance using kernel 3.4
Date: Wed, 30 May 2012 20:42:39 +0200
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To: Mark Nelson <mark.nelson@inktank.com>
Cc: Stefan Majer <stefan.majer@gmail.com>, "ceph-devel@vger.kernel.org" <ceph-devel@vger.kernel.org>

Hi Mark,

> Specifically, the gap in the movie where there is no write activity
> around second 30 correlates in the blktrace results with one of these
> stalls:
>> 8,16 0 0 29.548567957 0 m N cfq schedule dispatch
>> 8,16 2 2185 34.548923918 2688 A W 2192 + 8 <- (8,17) 144
>
> As to why this is happening, I don't know yet. I'll have more later.
Should i try the bisect thing?

Stefan