Re: Still seeing hangs in xlog_grant_log_space

Dave Chinner
2012-04-25T22:38:50Z

On Tue, Apr 24, 2012 at 08:26:04PM +0200, Juerg Haefliger wrote:
> On Tue, Apr 24, 2012 at 2:07 PM, Dave Chinner <david@fromorbit.com> wrote:
> > On Tue, Apr 24, 2012 at 10:55:22AM +0200, Juerg Haefliger wrote:
> >> > Alright, then I need all the usual information. I suspect an event
> >> > trace is the only way I'm going to see what is happening. I just
> >> > updated the FAQ entry, so all the necessary info for gathering a
> >> > trace should be there now.
> >> >
> >> > http://xfs.org/index.php/XFS_FAQ#Q:_What_information_should_I_include_when_reporting_a_problem.3F
> >>
> >> Very good. Will do. What kernel do you want me to run? I would prefer
> >> our current production kernel (2.6.38-8-server) but I understand if
> >> you want something newer.
> >
> > If you can reproduce it on a current kernel - 3.4-rc4 if possible, if
> > not a 3.3.x stable kernel would be best. 2.6.38 is simply too old to
> > be useful for debugging these sorts of problems...
>
> OK, I reproduced a hang running 3.4-rc4. The data is here but it's a
> whopping 2GB (yes it's compressed):
> https://region-a.geo-1.objects.hpcloudsvc.com:443/v1.0/AUTH_9630ead2-6194-40df-afd3-7395448d4536/xfs-hang/report-2012-04-24.tar

That's a bit big to be useful, and far bigger than I'm willing to
download given that I'm on the end of a wet piece of string, not a
big fat intarwebby pipe. I'm assuming it is the event trace
that is causing it to blow out? If so, just the 30-60s either side of
the hang first showing up is probaby necessary, and that should cut
the size down greatly....

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com