Re: 2.6.36 io bring the system to its knees

[Arjan van de Ven]

On Fri, 5 Nov 2010 08:48:13 -0400
Sanjoy Mahajan <sanjoy@xxxxxxxx> wrote:

> Dave Chinner <david@xxxxxxxxxxxxx> wrote:
> 
> > I think anyone reporting a interactivity problem also needs to
> > indicate what their filesystem is, what mount paramters they are
> > using, what their storage config is, whether barriers are active or
> > not, what elevator they are using, whether one or more of the
> > applications are issuing fsync() or sync() calls, and so on.
> 
> Good idea.  
> 
> The filesystems are all ext3 with default mount parameters.  The
> dmesgs say that the filesystems are mounted in ordered data mode and
> that barriers are not enabled.

btw few more things to try (from my standard rc.local script):

echo 4096 > /sys/block/sda/queue/nr_requests

for i in `pidof kjournald` ; do ionice -c1 -p $i ; done

echo 75 >  /proc/sys/vm/dirty_ratio


(replace sda with whatever your disk is of course)

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
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