Re: [Xen-devel] soft lockups during live migrate..

[Tim Deegan <Tim.Deegan@xxxxxxxxxx>]

At 11:09 +0100 on 23 Oct (1256296176), Tim Deegan wrote:
> At 05:21 +0100 on 23 Oct (1256275309), Mukesh Rathor wrote:
> > Trying to migrate a 64bit PV guest with 64GB running medium to heavy load 
> > on xen 3.4.0, it is showing lot of soft lockups. The softlockups are 
> > causing dom0 reboot by the cluster FS. The hardware has 256GB and 32
> > CPUs.
> > 
> > Looking into the hypervisor thru kdb, I see one cpu in sh_resync_all()
> > while all other 31 appear spinning on the shadow_lock.
> 
> How many vcpus does the guest have?  Scalability issues in the OOS
> shadow code are more related to number of VCPUs than amount of RAM.

With my brain in gear, I realise that it must have 32. :)  Yes, that's
likely to be well past the point of diminishing returns for OOS. 

Tim.

> > I vaguely remember
> > seeing some thread on this while ago, but just can't seem to google find
> > it now. I'm trying to figure what could be done in the short run.
> 
> The solution (for BS2000) was to plumb in a flag that disabled the OOS
> code for particular domains. 
>  
> Tim.
> 
> -- 
> Tim Deegan <Tim.Deegan@xxxxxxxxxx>
> Principal Software Engineer, Citrix Systems (R&D) Ltd.
> [Company #02300071, SL9 0DZ, UK.]

-- 
Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Citrix Systems (R&D) Ltd.
[Company #02300071, SL9 0DZ, UK.]

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel