nova修改libvirt.xml及自定义xml文件修改nova代码支持vhost

<interface type='bridge'>

<mac address='00:1a:4a:4d:63:a0'/>

<source bridge='sdcos-vmnet'/>

<model type='virtio'/>

<filterref filter='vdsm-no-mac-spoofing'/>

<link state='up'/>

<bandwidth>

</bandwidth>

<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>

<driver name='qemu'/>

</interface>

<interface type="bridge">

<mac address="fa:16:3e:ea:69:50"/>

<model type="virtio"/>

<source bridge="qbr3bcc4870-b3"/>

<target dev="tap3bcc4870-b3"/>

<driver name='qemu'/> #加上此配置文件，则启动的虚拟机参数中就会有vhost=off

修改nova代码支持：

def get_config(self,instance,vif,image_Meta,inst_type): conf = vconfig.LibvirtConfigGuestInterface() # Default to letting libvirt / the hypervisor choose the model model = None driver = None # If the user has specified a 'vif_model' against the # image then honour that model if image_Meta: vif_model = image_Meta.get('properties', {}).get('hw_vif_model') if vif_model is not None: model = vif_model # Else if the virt type is KVM/QEMU,use virtio according # to the global config parameter if (model is None and CONF.libvirt.virt_type in ('kvm','qemu') and CONF.libvirt.use_virtio_for_bridges): model = "virtio" # Workaround libvirt bug,where it mistakenly # enables vhost mode,even for non-KVM guests if model == "virtio" and CONF.libvirt.virt_type == "qemu": driver = "qemu"

修改为：

if model == "virtio" and CONF.libvirt.virt_type == "qemu": driver = "qemu" driver = "qemu"//增加此句，代表永远为qemu