From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: 2.6.23-rc6: hanging ext3 dbench tests
Date: Mon, 24 Sep 2007 12:12:55 -0700
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Cc: Andy Whitcroft <apw@shadowen.org>,
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To: Badari Pulavarty <pbadari@gmail.com>
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On Mon, 24 Sep 2007 11:01:58 -0700
Badari Pulavarty <pbadari@gmail.com> wrote:

> Hi Andy,
> 
> I managed to reproduce the dbench problem. (not sure if its the same
> thing or not - but symptoms are same). My problem has nothing to do 
> with ext3. I can produce it on ext2, jfs also.
> 
> Whats happening on my machine is ..
> 
> dbench forks of 4 children and sends them a signal to start the work.
> 3 out of 4 children gets the signal and does the work. One of the child
> never gets the signal so, it waits forever in pause(). So, parent waits
> for a longtime to kill it.
> 
> BTW, I was trying to find out when this problem started showing up.
> So far, I managed to track it to 2.6.23-rc4. (2.6.23-rc3 doesn't seem
> to have this problem). I am going to do bi-sect and find out which
> patch caused this.
> 
> I am using dbench-2.0 which consistently reproduces the problem on
> my x86-64 box. Did you find anything new with your setup ?
> 

Thanks, Badari.  That sounds like a bit of a showstopper for 2.6.23.
Michal, do you have this regression in the dirt file?