On 09/19/2014 03:42 AM, Gonglei (Arei) wrote: >> Subject: [Qemu-devel] [question] virtio-net-device and multi-queue option >> >> Hi, >> >> >> I am currently doing some benchmarks using virtio-net-device using >> virtio-mmio (non PCI) with qemu_system_arm with KVM. Purpose is to >> compare with device passthrough performance. >> >> I heard about the availability of a multi-queue option that greatly >> improves the performance but I currently fail in enabling it. >> >> Please could someone explain me how to turn that feature on? My current >> virtio-net options simply are: >> >> -netdev tap,id=tap0,ifname="tap0" \ >> -device virtio-net-device,netdev=tap0 >> > > There are some steps: > > 1. create multi-queue netdev device, such as tap device (you can > use "ip tuntap" command, or libvirt), something like as below: > ip tuntap add tap_1 mode tap multi_queue > 2. pass corresponding parameters in QEMU command line: > -netdev > type=tap,ifname=tap_q,id=net1,vhost=on,vhostforce=on,queues=4,script= \ > -device virtio-net-device,netdev=net1,mq=on,vectors=9
Hi Gonglei, Thanks for your quick reply. Definitively I have not gone through step 1! Nethertheless I am a but dubious about the fact the mq property does not seem to exist for my virtio-net-device. I get qemu-system-arm: -device virtio-net-device,netdev=tap0,mq=on,mac=52:54:00:12:34:56: Property '.mq' not found Best Regards Eric > >> Also are there any "easy" tunings I can play with to try to reach the >> best performance. >> > > You can consider that using irq binding, core binding, vhost-net? etc.. > > Best regards, > -Gonglei > >> Thank you in advance >> >> Best Regards >> >> Eric >
