Re: 2.4.31 hangs, no information on console or serial port

[Willy Tarreau <willy@w.ods.org>]

On Tue, Feb 21, 2006 at 11:04:57AM -0500, David Golombek wrote:
> Benjamin LaHaise <bcrl@kvack.org> writes:
> > On Tue, Feb 21, 2006 at 10:23:56AM -0500, David Golombek wrote:
> > > Any suggestions as to how we might debug this or possible causes would
> > > be greatly appreciated.
> > 
> > Have you tried turning on the NMI watchdog (nmi_watchdog=1)?  It
> > should be able to kick the machine out of the locked state, as these
> > symptoms would hint at a spinlock deadlock with interrupts disabled.
> > Also, try to reproduce on the latest 2.4.33pre.  That said, for an
> > io intensive workload like you're running, 2.6 is much better,
> > especially for systems using highmem.
> 
> I'll enable nmi_watchdog as soon as we can bring the machine down,
> thanks for the excellent suggestion. I'd entirely forgotten about the
> watchdog.  I'll try to switch to 2.4.33pre out as soon as poosible, it
> certainly has several fixes we've been waiting for.  2.6 is still a
> ways off, lots of qualification work to do.

BTW, if your console blanks, you should use this :

   # setterm -blank 0

Maybe you'll notice some "OOM: killing process" messages indicating
that some hungry process is going mad (possibly the NFS server).

> Thanks,
> Dave

Regards,
Willy