From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark McLoughlin Subject: Re: [PATCH 0/9][RFC] KVM virtio_net performance Date: Thu, 24 Jul 2008 17:53:51 +0100 Message-ID: <1216918431.19183.10.camel@muff> References: <1216899979-32532-1-git-send-email-markmc@redhat.com> Reply-To: Mark McLoughlin Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Herbert Xu , Rusty Russell To: kvm@vger.kernel.org Return-path: Received: from mx1.redhat.com ([66.187.233.31]:52533 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205AbYGXQyH (ORCPT ); Thu, 24 Jul 2008 12:54:07 -0400 In-Reply-To: <1216899979-32532-1-git-send-email-markmc@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Hey, One all all-important thing I forgot to include was a comparison with lguest :-) netperf, 10x20s runs (Gb/s) | guest->host | host->guest -----------------------------+----------------------------+--------------------------- KVM | 4.230/ 4.619/ 4.780/ 0.155 | 8.140/ 8.578/ 8.770/ 0.162 lguest | 5.700/ 5.926/ 6.150/ 0.132 | 8.680/ 9.073/ 9.320/ 0.205 ping -f -c 100000 (ms) | guest->host | host->guest -----------------------------+----------------------------+--------------------------- KVM | 0.199/ 0.326/ 7.698/ 0.744 | 0.199/ 0.245/ 0.402/ 0.022 lguest | 0.022/ 0.055/ 0.467/ 0.019 | 0.019/ 0.046/89.249/ 0.448 So, puppies gets you an extra 1.3Gb/s guest->host, .5Gb/s host->guest and much better latency. Actually, I guess the main reason for the latency difference is that when lguest gets notified on the tx ring, it immediately sends whatever is available and then starts a timer. KVM doesn't send anything until it's tx timer fires or the ring is full. Cheers, Mark.