Re: [kvm-devel] problems running many guests

[Marcelo T. <mto...@re...>]

On Thu, May 01, 2008 at 06:00:44PM -0500, Karl Rister wrote:
> Hi
> 
> I have been trying to do some testing of a large number of guests (72) on a 
> big multi-node IBM box (8 sockets, 32 cores, 128GB) and I am having various 
> issues with the guests.  I can get the guests to boot, but then I start to 
> have problems.  Some guests appear to stall doing I/O and some become 
> unresponsive and spin their single vcpu at 100%.

Does -no-kvm-irqchip or -no-kvm-pit makes a difference? If not, please
grab kvm_stat --once output when that happens.

Also run "readprofile -r ; readprofile -m System-map-of-guest.map" with the 
host booted with "profile=kvm". Make sure all guests are running the same kernel
image. 

The profiling should be easier to understand if you have 1 guest spinning and 
remaining ones idle.