2008-07-18 19:07:51

by J. Bruce Fields

[permalink] [raw]
Subject: Re: NFS hangs with 2.6.25/2.6.26 despite server being reachable

On Thu, Jul 17, 2008 at 11:04:05PM -0700, Michel Lespinasse wrote:
> On Wed, Jul 16, 2008 at 03:15:53PM -0400, J. Bruce Fields wrote:
> > On Tue, Jul 15, 2008 at 10:40:53PM -0700, Michel Lespinasse wrote:
> > > I'm getting frequent NFS hangs when running 2.6.25 or 2.6.26 on my
> > > NFS clients, while 2.6.24 seems to work fine.
> > > [...]
> > > Any ideas about what might be going wrong and/or what additional
> > > information I should try to collect about the hangs ?
> >
> > A sysrq-T trace showing where the clients were hung might help. (So,
> > "echo T >/proc/sysrq-trigger", then look at the logs.)
>
> Thanks for the reply. I'm now running 2.6.25.11 with sysrq enabled.
> Have not captured the failure yet, but then again it's been only one night.
> I prefer to go with 2.6.25 instead of 2.6.26 because 2.6.25 generally
> recovers from the failure after a few minutes - so there is a higher chance
> that I'll actually get something useful logged.
>
> > If it were possible to get it down to a simple test case, then we'd
> > probably learn something from a git-bisect to figure out exactly when
> > the problem was first introduced.
>
> I wish I had a better way to reproduce this... as it is it happens only
> every 2 or 3 days (with 2.6.25.4, but I suppose 2.6.25.11 will be the same)
>
> I'll let you know when I capture a good trace.

OK, thanks.

--b.