From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: Re: Regression in throughput between kvm guests over virtual bridge Date: Tue, 31 Oct 2017 15:00:56 +0800 Message-ID: References: <129a01d9-de9b-f3f1-935c-128e73153df6@linux.vnet.ibm.com> <3f824b0e-65f9-c69c-5421-2c5f6b349b09@redhat.com> <78678f33-c9ba-bf85-7778-b2d0676b78dd@linux.vnet.ibm.com> <038445a6-9dd5-30c2-aac0-ab5efbfa7024@linux.vnet.ibm.com> <20171012183132.qrbgnmvki6lpgt4a@Wei-Dev> <376f8939-1990-abf6-1f5f-57b3822f94fe@redhat.com> <20171026094415.uyogf2iw7yoavnoc@Wei-Dev> <20171031070717.wcbgrp6thrjmtrh3@Wei-Dev> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: mst@redhat.com, netdev@vger.kernel.org, davem@davemloft.net To: Wei Xu , Matthew Rosato Return-path: Received: from mx1.redhat.com ([209.132.183.28]:49150 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751539AbdJaHBN (ORCPT ); Tue, 31 Oct 2017 03:01:13 -0400 In-Reply-To: <20171031070717.wcbgrp6thrjmtrh3@Wei-Dev> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 2017年10月31日 15:07, Wei Xu wrote: >>> BTW, did you see any improvement when running pktgen from the host if no >>> regression was found? Since this can be reproduced with only 1 vcpu for >>> guest, may you try this bind? This might help simplify the problem. >>> vcpu0 -> cpu2 >>> vhost -> cpu3 >>> pktgen -> cpu1 >>> >> Yes -- I ran the pktgen test from host to guest with the binding >> described. I see an approx 5% increase in throughput from 4.12->4.13. >> Some numbers: >> >> host-4.12: 1384486.2pps 663.8MB/sec >> host-4.13: 1434598.6pps 688.2MB/sec > That's great, at least we are aligned in this case. > > Jason, any thoughts on this? > > Wei > Good news is that pps is increased. I think the first step is moving things a little bit ahead by reposting the optimization of tx polling. I will post a new version soon. Thanks