From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-x231.google.com (mail-lb0-x231.google.com [IPv6:2a00:1450:4010:c04::231]) by dpdk.org (Postfix) with ESMTP id E1B6E1F3 for ; Sun, 22 Sep 2013 21:03:02 +0200 (CEST) Received: by mail-lb0-f177.google.com with SMTP id w7so2011992lbi.8 for ; Sun, 22 Sep 2013 12:03:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=K0aljcHQvlzgvJj/w88WDbVKZVcD/XAG+dZdK61wthw=; b=haADdHrSEDlMey0LhsyoC9SZQ+cY7GQnlcIcvCmN/IrcG3uoJ8dDGPnlzV98cvcFhm oJ8QgnAtby8ZIJjPcRUOjD6pBPqFASQJJgtjPVJpsk5OpPsdjD6tUlcfY7nPZaLpNKE0 XyV3yboehNmYZ+p1Z/cCWKUNO2+E/2oOHXgadJTykFTKaGaZ+SBFccFQIxui+xVVXGVH PmIoX4obTRPkHHi3ZbuuEBExpsOIyNHJK9/ROe8VmrpY/UforP837Ek/iDlaHM7S/eBL cxDtl3ZVwoaJvW4yCfmN3JHMh/Lb3byrOI7W9T8oVeHc78gSpu2bOp5xR2UEt9kb+Gc4 IHUg== X-Received: by 10.112.9.195 with SMTP id c3mr66637lbb.33.1379876622230; Sun, 22 Sep 2013 12:03:42 -0700 (PDT) Received: from [192.168.0.51] ([176.104.197.138]) by mx.google.com with ESMTPSA id i3sm10871949laf.4.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sun, 22 Sep 2013 12:03:41 -0700 (PDT) Message-ID: <523F3F0C.2010104@gmail.com> Date: Sun, 22 Sep 2013 23:03:40 +0400 From: Dmitry Vyal User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: Robert Sanford References: <523AACC9.8010304@gmail.com> <523BEFA3.4070209@gmail.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: dev@dpdk.org Subject: Re: [dpdk-dev] How to fight forwarding performance regression on large mempool sizes. 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: Sun, 22 Sep 2013 19:03:03 -0000 On 09/20/2013 07:34 PM, Robert Sanford wrote: > One more point, if you're not doing this already: Allocate 2^N-1 > mbufs, not 2^N. According to the code and comments: "The optimum size > (in terms of memory usage) for a mempool is when n is a power of two > minus one: n = (2^q - 1)." > Many thanks! Didn't know about it.