[libvirt] [PATCH v2 0/4] Add cpu hotplug support to libvirt.

[Viktor Mihajlovski]

On 09/05/2012 07:32 AM, Tang Chen wrote:

>
> 4) Make libvirt not use cpuset cgroup.
>     - For now, seems impossable.
>       sched_setaffinity() behaves properly, which assumes the repluged
>       cpu is the same one unpluged before. (am I right ?)
>       But with cgroup's control, we cannot resolve this problem using
>       sched_setaffinity().
>
>
> If I want to solve the start failure problem, what should I do ?

Hi,

I posted a comment some time ago about that. If you do not mount the 
cpuset controller, i.e for RHEL 6 you delete the cpuset line from 
/etc/cgconfig, the CPU affinity isn't controlled by cgroups any more but 
uses the old mechanism, which works as expected: take a host CPU offline 
and it will be removed from the process CPU mask and will show up again 
after onlining the host CPU.
The only issue I currently see is that the display of virsh vcpuinfo and 
vcpupin is somewhat strange. Using taskset will however show the the 
correct affinity.

I suggest that you try out that approach.


-- 

Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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