Re: [Xen-users] Xen system hang or freeze

[Peter Booth <peter_booth@xxxxxxx>]

Nick,

When you got the "soft lockup" errors were they always with CPU0?
Do you have any nesting in your LVM definitions?
Is dom0 making use of LVM?
Does the host have a wireless card?
What graphics card does it have?

There is a Xen 2.6.18 kernel bug that might be related to what you  
see, as well as a patch:
http://www.mail-archive.com/debian-kernel@xxxxxxxxxxxxxxxx/msg40893.html

I appreciate that this freezing occurs when the system is quiet, but  
it seems as if the hypervisor CPU scheduler might play some part in  
this, such that the guest vcpus don't get scheduled on a pcpu. If it  
were me I would try limiting dom0 to four vcpus - not as a long-term  
configuration, but to see whether the problem recurred when we know  
that each domU should have an available CPU.
On Apr 23, 2009, at 4:47 PM, Nick Anderson wrote:

> On Thu, Apr 23, 2009 at 04:27:49PM -0400, Peter Booth wrote:
> > Nick,
> > How many vcpus does Dom0 have?
> ~# xm vcpu-list
> Name                                ID  VCPU   CPU State   Time(s) CPU
> Affinity
> Domain-0                             0     0     2   -b-    3603.1 any
> cpu
> Domain-0                             0     1     3   -b-      46.7 any
> cpu
> Domain-0                             0     2     6   -b-     380.0 any
> cpu
> Domain-0                             0     3     5   -b-     140.6 any
> cpu
> Domain-0                             0     4     0   -b-      46.4 any
> cpu
> Domain-0                             0     5     1   -b-      41.2 any
> cpu
> Domain-0                             0     6     5   -b-      34.7 any
> cpu
> Domain-0                             0     7     3   r--      69.9 any
> cpu
> domU1                                1     0     1   -b-   14154.7 any
> cpu
> domU2                                2     0     4   -b-   98047.2 any
> cpu
> domU3                                3     0     0   -b-    8588.2 any
> cpu
>
> --
> Nick Anderson <nick@xxxxxxxxxxxx>
> http://www.cmdln.org
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users