Para-Virt DomU + HVM DomU with xen 4.1.1 & linux 3.0.6 locks up system

Para-Virt DomU + HVM DomU with xen 4.1.1 & linux 3.0.6 locks up system

[Anthony Wright]

I have xen 4.1.1 running with a 3.0.6 linux kernel, both 32 bit.

If I run 2 x para-virtualized DomUs they run fine. If I run 2 x HVM
DomUs they run fine. If I run 1 x para-virtualized and 1 x HVM DomU (it
doesn't matter which one is run first & which second), the system locks
up just after I start the second DomU.

Re: Para-Virt DomU + HVM DomU with xen 4.1.1 & linux 3.0.6 locks up system

[Konrad Rzeszutek Wilk]

On Fri, Oct 14, 2011 at 02:35:13PM +0100, Anthony Wright wrote:
> I have xen 4.1.1 running with a 3.0.6 linux kernel, both 32 bit.
> 
> If I run 2 x para-virtualized DomUs they run fine. If I run 2 x HVM
> DomUs they run fine. If I run 1 x para-virtualized and 1 x HVM DomU (it
> doesn't matter which one is run first & which second), the system locks
> up just after I start the second DomU.

Locks up you say? When you launch the second guest, can you
also run 'while (true); do; xl list; sleep 1; done' to see if the memory
for Dom0 is going down to unreasonable amount?

Re: Para-Virt DomU + HVM DomU with xen 4.1.1 & linux 3.0.6 locks up system

[Pasi Kärkkäinen]

On Fri, Oct 14, 2011 at 10:00:30AM -0400, Konrad Rzeszutek Wilk wrote:
> On Fri, Oct 14, 2011 at 02:35:13PM +0100, Anthony Wright wrote:
> > I have xen 4.1.1 running with a 3.0.6 linux kernel, both 32 bit.
> > 
> > If I run 2 x para-virtualized DomUs they run fine. If I run 2 x HVM
> > DomUs they run fine. If I run 1 x para-virtualized and 1 x HVM DomU (it
> > doesn't matter which one is run first & which second), the system locks
> > up just after I start the second DomU.
> 
> Locks up you say? When you launch the second guest, can you
> also run 'while (true); do; xl list; sleep 1; done' to see if the memory
> for Dom0 is going down to unreasonable amount?
> 

Also are you using dom0_mem= for Xen? and did you disable dom0 ballooning?

Try enabling serial console and capturing all the Xen+dom0 console output..
http://wiki.xen.org/xenwiki/XenSerialConsole

-- Pasi

Re: Para-Virt DomU + HVM DomU with xen 4.1.1 & linux 3.0.6 locks up system

[Anthony Wright]

On 14/10/2011 15:00, Konrad Rzeszutek Wilk wrote:
> On Fri, Oct 14, 2011 at 02:35:13PM +0100, Anthony Wright wrote:
>> I have xen 4.1.1 running with a 3.0.6 linux kernel, both 32 bit.
>>
>> If I run 2 x para-virtualized DomUs they run fine. If I run 2 x HVM
>> DomUs they run fine. If I run 1 x para-virtualized and 1 x HVM DomU (it
>> doesn't matter which one is run first & which second), the system locks
>> up just after I start the second DomU.
> Locks up you say? When you launch the second guest, can you
> also run 'while (true); do; xl list; sleep 1; done' to see if the memory
> for Dom0 is going down to unreasonable amount?
It behaves as if it's run out of memory as you say, but I did 'while
true; do; xl list; sleep 0.2 ; done' on one session while I started the
other DomU, and the system locked so quickly that the xl list didn't see
any drop in Dom0 memory or the DomU even start.

I have given Dom0 1000MB, and the HVM DomU also uses 1000MB (though it
gets reported as 995MB). The para-virtual DomU uses 2000MB, and the
machine has 8GB. Before I start the para-virtual DomU the commited
AS_limit is around 141MB