Re: [libvirt] question for <interface> in ethernet type and multiple queues in KVM (start VM failed)

> > > > I use ethernet vif for VM (libvirt 1.1.0 qemu 1.5.1). xml as such > > > > <interface type='ethernet'> > > <script path='' /> > > <target dev='tap_mq'/> > > <mac address='52:54:00:19:9e:4e'/> > > <model type='virtio' /> > > <driver name='vhost' queues='2'/> > > </interface> > > > > tap_mq is a tap device with multi_queue property which was created > on host by ip command, such as follows > > #ip tuntap add tap_mq mode tap multi_queue > > > > I want to use multiple queue feature for this vif so I set queues='2' in > xml. > > > > When start VM , an error occurs > > "error: unsupported configuration: Multiqueue network is not > supported for: ethernet". > > This error is reported from function qemuBuildInterfaceCommandLine > > > > /* Currently nothing besides TAP devices supports multiqueue. */ > > if (net->driver.virtio.queues > 0 && > > !(actualType == VIR_DOMAIN_NET_TYPE_NETWORK || > > actualType == VIR_DOMAIN_NET_TYPE_BRIDGE)) { > > virReportError(VIR_ERR_CONFIG_UNSUPPORTED, > > _("Multiqueue network is not supported > for: %s"), > > virDomainNetTypeToString(actualType)); > > return -1; > > } > > > > The comment specifies that only TAP device supports multiqueue. But > VIR_DOMAIN_NET_TYPE_ETHERNET is also TAP device I think. > > Even though the device is TAP device indeed, it's not from the libvirt > POV. Libvirt doesn't examine the target dev to see if it is TAP, > physical NIC, sit, ... whatever. Yep, but I think libvirt should provide this ability which process multi_queue of ethernet type. And the result is guaranteed by the emulator, such as Qemu.