From owner-freebsd-net@FreeBSD.ORG Sun Jul 6 08:13:49 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4811D1065674 for ; Sun, 6 Jul 2008 08:13:49 +0000 (UTC) (envelope-from andrew@modulus.org) Received: from email.octopus.com.au (host-122-100-2-232.octopus.com.au [122.100.2.232]) by mx1.freebsd.org (Postfix) with ESMTP id EAAB88FC1D for ; Sun, 6 Jul 2008 08:13:48 +0000 (UTC) (envelope-from andrew@modulus.org) Received: by email.octopus.com.au (Postfix, from userid 1002) id 212AA17336; Sun, 6 Jul 2008 18:13:46 +1000 (EST) X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on email.octopus.com.au X-Spam-Level: X-Spam-Status: No, score=-1.4 required=10.0 tests=ALL_TRUSTED autolearn=failed version=3.2.3 Received: from [10.20.30.101] (60.218.233.220.exetel.com.au [220.233.218.60]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: admin@email.octopus.com.au) by email.octopus.com.au (Postfix) with ESMTP id 0F1C717259 for ; Sun, 6 Jul 2008 18:13:42 +1000 (EST) Message-ID: <48707EA6.2020506@modulus.org> Date: Sun, 06 Jul 2008 18:13:26 +1000 From: Andrew Snow User-Agent: Thunderbird 1.5.0.9 (Windows/20061207) MIME-Version: 1.0 To: freebsd-net@freebsd.org References: <4867420D.7090406@gtcomm.net> <20080701033117.GH83626@cdnetworks.co.kr><4869ACFC.5020205@gtcomm.net> <4869B025.9080006@gtcomm.net><486A7E45.3030902@gtcomm.net> <486A8F24.5010000@gtcomm.net><486A9A0E.6060308@elischer.org> <486B41D5.3060609@gtcomm.net><486B4F11.6040906@gtcomm.net><486BC7F5.5070604@gtcomm.net><20080703160540.W6369@delplex.bde.org><486C7F93.7010308@gtcomm.net><20080703195521.O6973@delplex.bde.org><486D35A0.4000302@gtcomm.net><486DF1A3.9000409@gtcomm.net><486E65E6.3060301@gtcomm.net> <2d3001c8def1$f4309b90$020b000a@bartwrkstxp> <48704E15.1070803@elischer.org> In-Reply-To: <48704E15.1070803@elischer.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: Freebsd IP Forwarding performance (question, and some info) [7-stable, current, em, smp] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Jul 2008 08:13:49 -0000 I'm no expert, but I imagine the problem is because the net processing of FreeBSD is not pipelined enough. We are now able to affordably throw many gigabytes of RAM into a machine, as well 2 to 8 CPUs. So why not allow for big buffers and multiple processing steps? I be happy to give up a bit of latency in order to increase the parallel processing ability of packets travelling through the system. I could be wrong but I imagine it would be better to treat the processing of pockets as a series of stages with queues (that can grow quite large if necessary).