From owner-freebsd-net@FreeBSD.ORG Sun Jan 11 14:01:37 2004 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2734716A4CE for ; Sun, 11 Jan 2004 14:01:37 -0800 (PST) Received: from silver.he.iki.fi (helenius.fi [193.64.42.241]) by mx1.FreeBSD.org (Postfix) with ESMTP id A4E9143D1F for ; Sun, 11 Jan 2004 14:01:32 -0800 (PST) (envelope-from pete@he.iki.fi) Received: from he.iki.fi (localhost [127.0.0.1]) by silver.he.iki.fi (8.12.9p2/8.11.4) with ESMTP id i0BM1Ugr031179; Mon, 12 Jan 2004 00:01:30 +0200 (EET) (envelope-from pete@he.iki.fi) Message-ID: <4001C78A.3060904@he.iki.fi> Date: Mon, 12 Jan 2004 00:00:42 +0200 From: Petri Helenius User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.5) Gecko/20031007 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Bruce M Simpson References: <20040109171717.33976.qmail@web60804.mail.yahoo.com> <20040111195740.GK17555@saboteur.dek.spc.org> In-Reply-To: <20040111195740.GK17555@saboteur.dek.spc.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit cc: freebsd-net@freebsd.org cc: Richard Bejtlich Subject: Re: Paper on device polling and packet capture performance X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 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, 11 Jan 2004 22:01:37 -0000 Bruce M Simpson wrote: > I'd be happy to review other patches for this. My personal feeling though > >is that the actual performance increase may not be that great, but it's >a case of someone implementing it and doing the math. > > > Writing to memory, specially on SMP systems, is very expensive. So eliminating copies will give huge performance benefits. Where bpf can go hardly 500Mbps on dual CPU machine, memory mapped capture will reach 1.5-2.0Gbps. Pete