Re: kvm linux guest hanging for minutes at a time

[Thomas Fjellstrom <thomas@fjellstrom.ca>]

On August 9, 2011, Avi Kivity wrote:
> On 08/09/2011 05:31 PM, Thomas Fjellstrom wrote:
> > On August 9, 2011, Avi Kivity wrote:
> > >  On 08/09/2011 03:03 PM, Thomas Fjellstrom wrote:
> > >  >  >   Your guest isn't using kvmclock for some reason.  Is it
> > >  >  >   compiled in the guest kernel?  What are the contents of
> > >  >  >   /sys/devices/system/clocksource/clocksource0/available_clocksou
> > >  >  >   rce and
> > >  >  >   /sys/devices/system/clocksource/clocksource0/current_clocksour
> > >  >  >   ce (in the guest filesystem)?
> > >  >  
> > >  >  Hi, it seems it is using kvm-clock:
> > >  >  
> > >  >  $ cat
> > >  >  /sys/devices/system/clocksource/clocksource0/available_clocksource
> > >  >  kvm-clock hpet acpi_pm
> > >  >  $ cat
> > >  >  /sys/devices/system/clocksource/clocksource0/current_clocksource
> > >  >  kvm-clock
> > >  
> > >  Yikes.  Please trace such a hang according to
> > >  http://www.linux-kvm.org/page/Tracing.
> > 
> > Does it matter that I have several vms running? Is there a way to limit
> > it to tracing the single kvm process that's been locking up?
> 
> You can use "trace-cmd record -F ... qemu ..." but that misses out on
> events the run from workqueues.
> 
> Best to stop those other guests.

I would prefer not to do that, those other guests are my web server, mail 
server, and database server. I have no idea if I can reproduce the problem in 
a reasonable time frame.

-- 
Thomas Fjellstrom
thomas@fjellstrom.ca