From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by dpdk.org (Postfix) with ESMTP id 693661B3B9 for ; Fri, 3 Nov 2017 08:47:18 +0100 (CET) Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Nov 2017 00:47:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,337,1505804400"; d="scan'208";a="331560036" Received: from fmsmsx108.amr.corp.intel.com ([10.18.124.206]) by fmsmga004.fm.intel.com with ESMTP; 03 Nov 2017 00:47:16 -0700 Received: from shsmsx152.ccr.corp.intel.com (10.239.6.52) by FMSMSX108.amr.corp.intel.com (10.18.124.206) with Microsoft SMTP Server (TLS) id 14.3.319.2; Fri, 3 Nov 2017 00:47:17 -0700 Received: from shsmsx102.ccr.corp.intel.com ([169.254.2.175]) by SHSMSX152.ccr.corp.intel.com ([169.254.6.93]) with mapi id 14.03.0319.002; Fri, 3 Nov 2017 15:47:15 +0800 From: "Yao, Lei A" To: Thomas Monjalon , "Wang, Zhihong" , "Li, Xiaoyun" CC: "dev@dpdk.org" , "Richardson, Bruce" , "Ananyev, Konstantin" , "Lu, Wenzhuo" , "Zhang, Helin" , "ophirmu@mellanox.com" Thread-Topic: [dpdk-dev] [PATCH v8 1/3] eal/x86: run-time dispatch over memcpy Thread-Index: AQHTRAJC5SptfEPRe0mJsN+gPF49naLoDmwAgABTEQCAAENNgIABVbcAgABG0gCAAA7OAIAAC6cAgAAE2YCAAAKvgIAACCUAgAEEqYCACD4lgIAACHCAgAZg+YCABmM1gIAABiIAgAHl17A= Date: Fri, 3 Nov 2017 07:47:14 +0000 Message-ID: <2DBBFF226F7CF64BAFCA79B681719D953A2CE048@shsmsx102.ccr.corp.intel.com> References: <1507206794-79941-1-git-send-email-xiaoyun.li@intel.com> <6811801.9Gdy4CqsrT@xps> <8F6C2BD409508844A0EFC19955BE0941513593EB@SHSMSX103.ccr.corp.intel.com> <2027509.fDzOy6Rher@xps> In-Reply-To: <2027509.fDzOy6Rher@xps> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiMjU1MDYzZGUtYTM4MC00NzEzLTlhMmEtN2EyNjIzODMzZjVkIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6Iis5MStSWnN4R0tqRHVcLzFZNlgyclFHZzhnZ3ZjZUVXSVNpV1g2Mjl4RTI0PSJ9 x-ctpclassification: CTP_IC dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [dpdk-dev] [PATCH v8 1/3] eal/x86: run-time dispatch over memcpy X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Nov 2017 07:47:21 -0000 Hi, Thomas > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Thomas Monjalon > Sent: Thursday, November 2, 2017 6:45 PM > To: Wang, Zhihong ; Li, Xiaoyun > > Cc: dev@dpdk.org; Richardson, Bruce ; > Ananyev, Konstantin ; Lu, Wenzhuo > ; Zhang, Helin ; > ophirmu@mellanox.com > Subject: Re: [dpdk-dev] [PATCH v8 1/3] eal/x86: run-time dispatch over > memcpy >=20 > 02/11/2017 11:22, Wang, Zhihong: > > > I don't know what is creating this drop exactly. > > > When doing different tests on different environments, we do not see > this > > > drop. > > > If nobody else can see such issue, I guess we can ignore it. > > > > Hi Thomas, Xiaoyun, > > > > With this patch (commit 84cc318424d49372dd2a5fbf3cf84426bf95acce) I see > > more than 20% performance drop in vhost loopback test with testpmd > > macswap for 256 bytes packets, which means it impacts actual vSwitching > > performance. > > > > Suggest we fix it or revert it for this release. >=20 > I think we need more numbers to take a decision. > What is the benefit of this patch? In which use-cases? > What are the drawbacks? In which use-cases? >=20 > Please, it is a call to test performance with and without this patch > in more environments (CPU, packet size, applications). Following is the performance drop we observe in vhost/virtio loopback perfo= rmance with and without this patch Test application: testpmd CPU info: Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz OS: Ubuntu 16.04 Mergebale Path=09 packet size Performance Drop 64 -1.30% 128 0.81% 158 -19.17% 188 -19.18% 218 -16.29% 230 -16.57% 256 -16.77% 280 -3.07% 300 -3.22% 380 -2.44% 420 -1.65% 512 -0.99% 1024 0.00% 1518 -0.68% =09 Vector Path=09 packet size Performance Drop 64 3.30% 128 7.18% 256 -12.77% 512 -0.98% 1024 0.27% 1518 0.68%