Re: [libvirt] [PATCH v2 0/4] Add cpu hotplug support to libvirt.
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.
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Viktor Mihajlovski
IBM Deutschland Research & Development GmbH
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