From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: xen drivers to use virtio? Date: Thu, 26 Feb 2009 20:30:36 -0600 Message-ID: <49A7504C.4010506@codemonkey.ws> References: <49A5DA20.2080306@goop.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <49A5DA20.2080306@goop.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jeremy Fitzhardinge Cc: xen-devel , Jun Koi List-Id: xen-devel@lists.xenproject.org Jeremy Fitzhardinge wrote: > Jun Koi wrote: >> If I understand correctly, we are going to rewrite some xen drivers in >> Linux kernel to use virtio once virtio is stable. Is that true? >> > > There are no plans to do so. Actually, they're already there to some degree now that qemu-dm is tracking the upstream QEMU tree. virtio support has been in the QEMU tree for some time now. If it's not enabled in qemu-dm by default, it should be trivial to enable. From Xend's perspective, virtio devices shouldn't be different from either rtl8139, e1000, etc. It's just another PCI device. This model makes less sense in the context of stub domains, but if you're running qemu-dm in dom0, you may actually get reasonable performance out of the virtio drivers. In fact, comparing an HVM domain using virtio with qemu-dm in dom0 verses netfront ala PV-on-HVM would make for a very interesting comparison. And assuming PV-on-HVM isn't in upstream Linux yet (that appears to be the case) and virtio is, it may even be a practical thing to do. Regards, Anthony Liguori > J