From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 0/9][RFC] KVM virtio_net performance Date: Sun, 27 Jul 2008 10:52:12 +0300 Message-ID: <488C292C.7020609@qumranet.com> References: <1216899979-32532-1-git-send-email-markmc@redhat.com> <4888EC61.8050208@codemonkey.ws> <488B7668.7090605@tmr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Anthony Liguori , Mark McLoughlin , kvm@vger.kernel.org, Herbert Xu , Rusty Russell To: Bill Davidsen Return-path: Received: from il.qumranet.com ([212.179.150.194]:55416 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750792AbYG0HwN (ORCPT ); Sun, 27 Jul 2008 03:52:13 -0400 In-Reply-To: <488B7668.7090605@tmr.com> Sender: kvm-owner@vger.kernel.org List-ID: Bill Davidsen wrote: > Anthony Liguori wrote: >> Hi Mark, >> >> Mark McLoughlin wrote: >>> Hey, >>> Here's a bunch of patches attempting to improve the performance >>> of virtio_net. This is more an RFC rather than a patch submission >>> since, as can be seen below, not all patches actually improve the >>> perfomance measurably. >>> >> >> I'm still seeing the same problem I saw with my patch series. >> Namely, dhclient fails to get a DHCP address. Rusty noticed that RX >> has a lot more packets received then it should so we're suspicious >> that we're getting packet corruption. > > I have been discussing this (on this list) in another thread. Putting > tcpdump on the eth0 device in the VM, the br0 device in the host, and > the eth0 (physical NIC) in the host, you can see that when the VM > generates a DHCP request it shows up on the br0 in the host, but never > gets sent on the wire by eth0. > > That's the point of failure, at least using RHEL5/FC6/kvm-66 as the > environment. Does playing with the bridge forward delay ('brctl setfd') help? -- error compiling committee.c: too many arguments to function