From: Lothar Braun <mail@lobraun.de>
To: jassduec@gmail.com
Cc: linux-admin@vger.kernel.org, linux-config@vger.kernel.org
Subject: Re: High iowait
Date: Tue, 22 Aug 2006 11:38:10 +0200 [thread overview]
Message-ID: <200608221138.15159.mail@lobraun.de> (raw)
In-Reply-To: <3a1eedb70608211931w67f86bccpb383bb0ff8089f45@mail.gmail.com>
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Hi,
On Tuesday 22 August 2006 04:31, jassduec@gmail.com wrote:
> I have a storage raid attached to my linux server running CentOS 4.3
> kernel 2.6.9-39.0.2.ELsmp. My server goes into huge iowait when i try
> to read/write lot of data to the storage device. How can i debug
> whether the problem is with the storage device or some setting of the
> operating system. Is there any known issue with this kernel? How can i
> tune my system to reduce iowait time?
Why should you want to reduce the iowait time? Iowait, as shown by top, means
afaik that there are some processes waiting for io to complete and nothing
else to do for the processor.
If you're running some CPU eating processes while your I/O operations are
performed, then the iowait value should go down (this is because your CPU can
then do more sophisticated work than waiting)
Regards,
Lothar
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next prev parent reply other threads:[~2006-08-22 9:38 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-08-22 2:31 High iowait jassduec
2006-08-22 9:38 ` Lothar Braun [this message]
2006-08-23 16:10 ` jassduec
2006-08-24 1:01 ` terry white
2006-08-24 20:06 ` Art Wildman
2006-08-25 18:59 ` how tell what specific device is sending an interrupt? tom arnall
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