Re: Consistent kernel hang during heavy TCP connection handling load

From: Jan Kara
Date: Mon Sep 27 2004 - 08:37:08 EST


Hello,

> Yes, I have reproduced the problem on another machine running a
> similar kernel but with different network card, CPU, etc.
OK, so it probably won't be hardware. Any debugging output? If I got
it right you are using RH kernel - can you try with the vanilla one from
ftp.kernel.org to rule out some RH specific patches? Can you send your
kernel configuration?

Honza

> -----Original Message-----
> From: Jan Kara
> Subject: Re: Consistent kernel hang during heavy TCP connection handling
> load
>
>
> Hello,
>
> > Thanks for responding. When I got no responses, I searched for ways
> I don't have personaly much experience with debugging by above tools
> so I won't be of much help. As you describe the problem below I
> personaly think that you won't get much from them if the system is as
> unresponsive as you write.
>
> > (3) Enabled sysrq on both kernels, including echo "1" > /proc/sys/kernel/sysrq
> >
> > I'll wait for the next hang now, trying it on both kernels. By the
> > way, the system is hung VERY badly--doesn't respond to anything, no
> > switching consoles, no keyboard events, no disk activity. Dunno about
> > network, since I haven't put a sniffer on it yet.
> Hmm.. that looks bad. Do you debug things under console and not
> in X? If that is the case either there is some hardware problem (you
> likely generate quite high load on the machine) or some driver is stuck
> with interrupts disabled. In case debugging tools don't help you can try
> to compile kernel with minimal config (just disable everything not
> needed to run the test). Also reproducing on a different machine would
> be useful to rule out hardware...
>
> Honza
>
>
>
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
--
Jan Kara <jack@xxxxxxx>
SuSE CR Labs
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/