Debugging a system hang.

[Naoki]

Hello Gents,

Sorry I didn't include all the version info etc because what I really
wanted was some general guidelines on kernel debugging so I could check
into this myself.

However as you're all so kind and want to know :)

No custom modules at all. It's out of the box. And the problem occurs
with both SMP and UP kernels of version 2.6.11-1.1369_FC4 #1 Thu Jun 2
22:56:33 EDT 2005 x86_64 x86_64 x86_64.

All I need to do is start an rsync over ssh from another machine of 8GB
(many files) and after a minute or two she's popped.

The closest thing to a trace I've managed to see is :

<3>Debug : Sleeping function called from invalid context at
include/linux/rwsem.h:43
in_atomic:(0) irqs_disabled:(1)

And I just saw something like this :

"Warning lost too many ticks
Your time source is instable or some driver is hogging interrupts."


Any ideas lads?

On Fri, 2005-09-02 at 07:29 +0200, Arjan van de Ven wrote:
> On Fri, 2005-09-02 at 12:29 +0900, Naoki wrote:
> > Hey all,
> > 
> > I was asking this back over on fedora-list but had no responses.
> > 
> > How do I debug a hung system?  My box doesn't (ibm e326 with FC4,
> > x86_64) actually panic and crash so lkcd is of no use(?) kgdb? How about
> > magic sys key ?
> > 
> > I can reliably make it hang to a point where the only working operations
> > I can see are a blinking cursor and replies to ping packets.
> 
> well which version exactly? what modules are in use?
> is there a backtrace?
> 
> -- 
> fedora-devel-list mailing list
> fedora-devel-list at redhat.com
> http://www.redhat.com/mailman/listinfo/fedora-devel-list
......................................................................................
Mark "Naoki" Rogers /VP - Systems Engineering
Systems
ValueCommerce Co., Ltd. 

Tokyo Bldg 4F 3-32-7 Hongo Bunkyo-ku Tokyo 113-0033 Japan
Tel. +81.3.3817.8995   Fax. +81.3.3812.4051
mailto:naoki at valuecommerce.co.jp
......................................................................................