[libvirt] [PATCHv2 1/3] qemu, lxc: Change host CPU detection logic.

Viktor Mihajlovski mihajlov at linux.vnet.ibm.com
Thu Nov 1 08:16:50 UTC 2012

On 11/01/2012 04:00 AM, Eric Blake wrote:
> On 10/31/2012 11:20 AM, Viktor Mihajlovski wrote:
>>       /* setaffinity fails if you set bits for CPUs which
>>        * aren't present, so we have to limit ourselves */
> Question - does setaffinity fail if you request setting a CPU that is
> present but offline?  In that case, we would need the CPU map instead of
> just the count of max cpus.  But in the meantime, I'm okay with your patch.

It will fail in the case you describe. Of course, with the new API it is 
possible for a client to determine the host CPU map beforehand allowing 
to specify a valid affinity mask. The other question is whether an 
incorrect mask should be corrected silently by libvirt or whether a 
reported error would be more appropriate.
All in all this needs more thought and discussion, IMO independent of 
this patch series.


Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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