finding reasons for disk spin ups

finding reasons for disk spin ups

[Norbert Preining]

Hi all,
(please cc)

is there a way I can find the reasons why my disk is spinning up again
and again? I tried to monitor io with
	iotop -o -d 0.01 -b -qqq -t
but sometimes the disks spins up without anything showing up.
The partitions are mounted with noatime.

Is there any kernel interface telling me why/whcih process called for
the sync so that the disk wakes up?

Thanks a lot

Norbert

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Dr. Norbert Preining <preining@logic.at>        Vienna University of Technology
Debian Developer <preining@debian.org>                         Debian TeX Group
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Re: finding reasons for disk spin ups

[Matthew Garrett]

On Tue, Jun 23, 2009 at 07:00:06PM +0200, Norbert Preining wrote:
> Hi all,
> (please cc)
> 
> is there a way I can find the reasons why my disk is spinning up again
> and again? I tried to monitor io with
> 	iotop -o -d 0.01 -b -qqq -t
> but sometimes the disks spins up without anything showing up.
> The partitions are mounted with noatime.
> 
> Is there any kernel interface telling me why/whcih process called for
> the sync so that the disk wakes up?

Yes. /proc/sys/vm/block_dump - set that to 1. Make sure you disable 
syslog first.

-- 
Matthew Garrett | mjg59@srcf.ucam.org