Open Stack

Hi, I'd like you to take a look at this patch for potential
DocImpact.
https://review.openstack.org/26363

Log:
commit f4ac5aee9a4d82a508627facf62de34691ab6594
Author: Wangpan <hzwangpan at corp.netease.com>
Date:   Mon Apr 8 17:57:10 2013 +0800

    Add cpuset attr to vcpu conf in libvirt xml
    
    Currently the instances can use all of the pcpu of compute node, the
    host may become slow when vcpus of instances are busy, so we need to
    pin vcpus to the specific pcpus of host instead of all pcpus.
    Also added a cache of total vcpus num in libvirt driver here.
    
    DocImpact
    Implements blueprint: instance-vcpu-pin
    Change-Id: I6b6e805c15b249cc5e7517e26619d79bb0183de8