From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f169.google.com (mail-yw0-f169.google.com [209.85.161.169]) by dpdk.org (Postfix) with ESMTP id 65E8B69EC for ; Fri, 17 Mar 2017 13:59:26 +0100 (CET) Received: by mail-yw0-f169.google.com with SMTP id v76so52450962ywg.0 for ; Fri, 17 Mar 2017 05:59:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc:content-transfer-encoding; bh=VXhGJ7HwRwcDhDfWvWHxWDrztDRPmNUi6QgU7SzXUkk=; b=R0+XdpRQnjaA4PnfTNy6OhkpMutiDv9PIWrEmFlclgWCwww0+gHQKIKqur8Sy+VZIQ 9Lbclrz5GRp1GPBlBGyk6XJKWrTVej3sxWTJc1HfbGKiOA6NINM/TQjqqh+rlZ3T7ttu SQb+J/tEd+MMNDErYV68EOLWuSmhO4ixDIX/OQ/wxgo7PYBoGGwBTulsls8kaW0e0KDW azgKXtn+Z0nDvVnMiuQARC6qIBAEq9juwrkpzoQU2Ij7vqIhvMwabs356ir9qaMK5JXp CMb4Wq+MoYZcXQ0qdexw6eQ1eR/MA+gWj28STWDhk6/7YUYU8g3uYa5JeM7ME52I2fPR Q37w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc:content-transfer-encoding; bh=VXhGJ7HwRwcDhDfWvWHxWDrztDRPmNUi6QgU7SzXUkk=; b=obBnffZjZhyH3AsJUw8F47d7rJaUuk1KOsJzyJr6nCw1M/982NzyUIigDqoDDWkFtv uvHvbYfPGcOnBqL6ONyRGDbotJqy+V8jdnfDT8O+wQuGvoASw6+Nj5rrRlpwHdtRg2fy u26+N4xryaqWX0VdlGgoeYPHXj5scclfg+gQI+7EHd76cGwH8l3VAgNAylj0/kAwaAXN Tgc3B1SL2DwNTvGcUl13v2k/cqG4poFlrKJMNE8ZNLjUUXLPLWwMRKufLzgNPGqvANn/ 5of2o0LSk9m/biQ0p+D5XzXNoB7fkkR9LmGFjNF3/KJxys+QzKTXujiFxfsSpFr9BGsA APfw== X-Gm-Message-State: AFeK/H1KKOzSXHNYY7mGmBirbEovBhRDgWT7TYXfS1Kd+Zo42m/6rL2ojrXl9y/BSe5V2K0muSNXzFZ9CqKiVg== X-Received: by 10.37.122.70 with SMTP id v67mr6050289ybc.2.1489755565477; Fri, 17 Mar 2017 05:59:25 -0700 (PDT) MIME-Version: 1.0 Sender: castet.j@gmail.com Received: by 10.129.172.91 with HTTP; Fri, 17 Mar 2017 05:59:25 -0700 (PDT) In-Reply-To: <0603B9A8-6CE9-45CA-AA98-4318E0F7E7EA@intel.com> References: <0603B9A8-6CE9-45CA-AA98-4318E0F7E7EA@intel.com> From: Julien Castets Date: Fri, 17 Mar 2017 13:59:25 +0100 X-Google-Sender-Auth: CZkvy08CcYQpa5FRB_APxoZrIBc Message-ID: To: "Wiles, Keith" Cc: "users@dpdk.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [dpdk-users] Behavior of pktgen's "rate" option X-BeenThere: users@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK usage discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 17 Mar 2017 12:59:26 -0000 On Fri, Mar 17, 2017 at 1:25 AM, Wiles, Keith wrote= : > > Be careful in how you setup and change the size of a packet. Changing the= size while Pktgen is running can lead to some weird performance. The probl= em is the packets already in flight are not changed to the new size or they= are stuck on the TX done queue. The new TX flush API needs to be added to = the PMDs and then in Pktgen I can flush all of the buffers back to the memp= ool and then alter the size of the mbuf. You did not state the version of P= ktgen you are using, as DPDK 16.11 added some support for pktgen to locate = and update all of the mbuf, I think that is kind of a hack on my part. Pktgen Ver: 3.1.2 (DPDK 17.02.0) > The code in Pktgen takes your rate and packet size to determine the numbe= r of packets to send at a given rate to obtain you desired rate. I thought = the calculation accounted for the number of TX cores, but maybe that is a = bug. I would have expected 16Gbps in the two core case if I did not account= for that config. I do not have direct access to the machine to verify the = code. > > Try stopping the traffic before changing any of the configs, changing the= rate should work while Pktgen is sending. The problem is if the size of co= ntent needs to change the system should be halted. Also if you want to do a= some more debugging, try quiting Pktgen between configurations and see if = that works better. It is not what I intended on the usage of Pktgen is to q= uit all of the time. To generate traffic, I'm loading the lua configuration file (attached to my first email) from pktgen. This lua file starts with: pktgen.stop("all"); pktgen.reset("all"); pktgen.clear("all"); So I'm not changing parameters while pktgen is sending. Anyway, the results are the same if I stop pktgen between tests: * 1 core, pktsize 64 bytes, rate 20: 8Gbps * 2 cores, pktsize 64 bytes, rate 20: 28Gbps * 1 core, pktsize 128 bytes, rate 20: 14Gbps > I will try to have a look this weekend when I get back home. Awesome! --=20 Julien Castets