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Re: [Xen-users] 100% iowait in domU with no IO tasks.

To: "Bogdan B. Rudas" <brudas@xxxxxxxxxxx>
Subject: Re: [Xen-users] 100% iowait in domU with no IO tasks.
From: Tomasz Chmielewski <mangoo@xxxxxxxx>
Date: Thu, 08 May 2008 11:06:15 +0200
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Bogdan B. Rudas schrieb:
Hi. I entered one of our domU tonight and see following problem:
# iowait -k 5

avg-cpu:  %user   %nice %system %iowait  %steal   %idle

           0.00    0.00    0.00  100.00    0.00    0.00

Device:            tps    kB_read/s    kB_wrtn/s    kB_read    kB_wrtn
sda1              0.00         0.00         0.00          0          0
sda2              0.00         0.00         0.00          0          0

I check other domU and dom0 on same server - there were high iowait: from 20% 
to 50% with few transactions per second and about 0.1-1.5 Mb/sec storage 
bandwith usage per domU. This domU have no disk IO at all but show LA 15 and 
possible higher.

Did you check for processes in a "D" state?

ps aux | grep " D"

Tomasz Chmielewski

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