On Wed, Aug 12, 2009 at 07:56:05AM -0400, Gregory Haskins wrote: > Michael S. Tsirkin wrote: > > On Tue, Aug 11, 2009 at 07:49:37PM -0400, Gregory Haskins wrote: > >> Michael S. Tsirkin wrote: > >>> This implements vhost: a kernel-level backend for virtio, > >>> The main motivation for this work is to reduce virtualization > >>> overhead for virtio by removing system calls on data path, > >>> without guest changes. For virtio-net, this removes up to > >>> 4 system calls per packet: vm exit for kick, reentry for kick, > >>> iothread wakeup for packet, interrupt injection for packet. > >>> > >>> Some more detailed description attached to the patch itself. > >>> > >>> The patches are against 2.6.31-rc4. I'd like them to go into linux-next > >>> and down the road 2.6.32 if possible. Please comment. > >> I will add this series to my benchmark run in the next day or so. Any > >> specific instructions on how to set it up and run? > >> > >> Regards, > >> -Greg > >> > > > > 1. use a dedicated network interface with SRIOV, program mac to match > > that of guest (for testing, you can set promisc mode, but that is > > bad for performance) > > Are you saying SRIOV is a requirement, and I can either program the > SRIOV adapter with a mac or use promis? Or are you saying I can use > SRIOV+programmed mac OR a regular nic + promisc (with a perf penalty). SRIOV is not a requirement. And you can also use a dedicated nic+programmed mac if you are so inclined. > > 2. disable tso,gso,lro with ethtool > > Out of curiosity, wouldnt you only need to disable LRO on the adapter, > since the other two (IIUC) are transmit path and are therefore > influenced by the skb's you generate in vhost? Hmm, makes sense. I'll check this and let you know. > > > 3. add vhost=ethX > > You mean via "ip link" I assume? No, that's a new flag for virtio in qemu: -net nic,model=virtio,vhost=veth0 > Regards, > -Greg > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
