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

On Fri, Apr 03, 2009 at 04:59:33PM +0100, Paraic Gallagher wrote:
> Thanks for the response. After searching net for few weeks with no luck
> in finding similar issues was beginning to think I was going crazy!
I'm feeling the same way I just can't seem to find anything that
points to an answer.

> All vms are LVM backed on this system except for Dom0.
> This seems to be quite a similar problem from the description, however I
> haven't
> noticed the guest vms locking up prior to Dom0. Something to keep an eye on.
> Are you running a particular load on the system at the time or is it
> somewhat
> idle? Seems to be idle in my case before lockup.

The domUs are defiantly not overloaded. I have had the lockups at
different loads and times but it most frequently happens during the
night (so lower load times). But I have had it occur in the middle of
the day as well.

When this first started I didn't notice the vms locking either. I
tightened up my monitoring so I could get faster notifications of any
one thing becoming unresponsive and that helped me get logged into
the dom0 in time to start looking at the domU that was locked. Also
this is not specific to any one domU. At first I thought it was but
time has proved me wrong and I have had each domU lock up similarly.
All of my domUs currently have only a single vcpu but at one point one
(the one I thought was the only domU locking) had 2 vcpus. This had no
bearing on the lockups as far as I could tell.

Again the only thing I have correlated was the appearance of
"softlockup detected on cpu" msgs on the domU consoles during an

I'm still baffled by how the server was unresponsive for 45 minutes
then became responsive again for about 10 minutes only to lockup again
and be unresponsive from the dom0 physical console.

Nick Anderson <nick@xxxxxxxxxxxx>

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