From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f50.google.com (mail-pa0-f50.google.com [209.85.220.50]) by dpdk.org (Postfix) with ESMTP id 39D891F3 for ; Mon, 2 Sep 2013 18:09:42 +0200 (CEST) Received: by mail-pa0-f50.google.com with SMTP id fb10so5363171pad.37 for ; Mon, 02 Sep 2013 09:10:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-type:content-transfer-encoding; bh=WJheowdGKoyFQufjzZMFcwAWF0of9XPwF1uZnN7HEpY=; b=Y4iLNcpUnaEqgQX4PZ1HJnkhrB69nVWQdtxDc43Gzb1pNRz4hg2pKynIPaxtboSkOO Ch9qdZxyMK1U7pTciFZlrZIXm7qXY6bdUy6qEhaVxwsePfP/RYa8PomaLmHFQb9KTx5R SRtSn70dbigZXi9AcF0UIZ8Sw+q/cGVcoskgYz9VPAb4vDzARHsf6YKPmTqmPl9s9mf7 RSh555J8xe1hWSE+oSpnDSH/YCr8vJLpxtaxuVyP5UdKw2MPVSInzHoN/tMnUVgGEQrX 5xjROwyuDNqBHA4HgrJJLhk7DxaDD5WRNVRK7kB6e2duQOEbHnx9co4k0alp95lgcaWW XtNg== X-Gm-Message-State: ALoCoQml9nPjfg8UnX8WqA9OqeUL8eSiYiNL/yY1ZedybG1D5w4l9XFs6ak4K3FWKEQb9U2mlbf/ X-Received: by 10.68.14.234 with SMTP id s10mr4215282pbc.139.1378138215336; Mon, 02 Sep 2013 09:10:15 -0700 (PDT) Received: from nehalam.linuxnetplumber.net (static-50-53-69-237.bvtn.or.frontiernet.net. [50.53.69.237]) by mx.google.com with ESMTPSA id ta10sm18048127pab.5.1969.12.31.16.00.00 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Mon, 02 Sep 2013 09:10:15 -0700 (PDT) Date: Mon, 2 Sep 2013 09:10:12 -0700 From: Stephen Hemminger To: Zachary Message-ID: <20130902091012.2e68b88e@nehalam.linuxnetplumber.net> In-Reply-To: <52240466.7050907@cas-well.com> References: <52240466.7050907@cas-well.com> X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org, "Yannic.Chou \(=?utf-8?B?5ZGo5ZOy5q2j?=\) : 6808" , "Alan Yu \(=?utf-8?B?5L+e5Lqm5YGJ?=\) : 6632" Subject: Re: [dpdk-dev] DPDK & QPI performance issue in Romley platform. X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 Sep 2013 16:09:42 -0000 On Mon, 2 Sep 2013 11:22:14 +0800 Zachary wrote: > Hi~ > > I have a question about DPDK & QPI performance issue in Romley platform. > Recently, I use DPDK example, l2fwd, to test DPDK's performance in my Romley platform. > When I try to do the test, crossing used CPU, I find the performance dramatically decrease. > Is it true? Or any method can prove the phenomenon? > > In my opinion, there should be no this kind of issue here due to QPI have enough bandwidth to deal the kinds of case. > Thus, I am so amaze in our results and can not explain it. > Could someone can help me to solve this problem. > > Thank a lot! Many DPDK API's have NUMA socket as one of the parameters. In order to get good performance it is up to the application to be NUMA aware and use socket local resources. One example we do is to have a packet mbuf pool per socket, and assign each device to the correct pool. Also, you may want to choose which lcore's to assign to which function based on socket locality. For example threads that are polling receiver should be on same socket as that NIC. Remember the example applications are demo toys, and don't do all the things a real application would need to do.