From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jianbo Liu Subject: Re: [PATCH v3 0/5] vhost: optimize enqueue Date: Thu, 22 Sep 2016 17:01:41 +0800 Message-ID: References: <1471319402-112998-1-git-send-email-zhihong.wang@intel.com> <1471585430-125925-1-git-send-email-zhihong.wang@intel.com> <8F6C2BD409508844A0EFC19955BE09414E7B5581@SHSMSX103.ccr.corp.intel.com> <20160922022903.GJ23158@yliu-dev.sh.intel.com> <8F6C2BD409508844A0EFC19955BE09414E7B5DAE@SHSMSX103.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: Yuanhan Liu , Maxime Coquelin , "dev@dpdk.org" To: "Wang, Zhihong" Return-path: Received: from mail-yw0-f172.google.com (mail-yw0-f172.google.com [209.85.161.172]) by dpdk.org (Postfix) with ESMTP id D0BD258D8 for ; Thu, 22 Sep 2016 11:01:42 +0200 (CEST) Received: by mail-yw0-f172.google.com with SMTP id g192so87064228ywh.1 for ; Thu, 22 Sep 2016 02:01:42 -0700 (PDT) In-Reply-To: <8F6C2BD409508844A0EFC19955BE09414E7B5DAE@SHSMSX103.ccr.corp.intel.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 22 September 2016 at 14:58, Wang, Zhihong wrote: > > >> -----Original Message----- >> From: Jianbo Liu [mailto:jianbo.liu@linaro.org] >> Sent: Thursday, September 22, 2016 1:48 PM >> To: Yuanhan Liu >> Cc: Wang, Zhihong ; Maxime Coquelin >> ; dev@dpdk.org >> Subject: Re: [dpdk-dev] [PATCH v3 0/5] vhost: optimize enqueue >> >> On 22 September 2016 at 10:29, Yuanhan Liu >> wrote: >> > On Wed, Sep 21, 2016 at 08:54:11PM +0800, Jianbo Liu wrote: >> >> >> > My setup consists of one host running a guest. >> >> >> > The guest generates as much 64bytes packets as possible using >> >> >> >> >> >> Have you tested with other different packet size? >> >> >> My testing shows that performance is dropping when packet size is >> more >> >> >> than 256. >> >> > >> >> > >> >> > Hi Jianbo, >> >> > >> >> > Thanks for reporting this. >> >> > >> >> > 1. Are you running the vector frontend with mrg_rxbuf=off? >> >> > >> Yes, my testing is mrg_rxbuf=off, but not vector frontend PMD. >> >> >> > 2. Could you please specify what CPU you're running? Is it Haswell >> >> > or Ivy Bridge? >> >> > >> It's an ARM server. >> >> >> > 3. How many percentage of drop are you seeing? >> The testing result: >> size (bytes) improvement (%) >> 64 3.92 >> 128 11.51 >> 256 24.16 >> 512 -13.79 >> 1024 -22.51 >> 1500 -12.22 >> A correction is that performance is dropping if byte size is larger than 512. > > > Jianbo, > > Could you please verify does this patch really cause enqueue perf to drop? > > You can test the enqueue path only by set guest to do rxonly, and compare > the mpps by show port stats all in the guest. > > Tested with testpmd, host: txonly, guest: rxonly size (bytes) improvement (%) 64 4.12 128 6 256 2.65 512 -1.12 1024 -7.02