From owner-freebsd-current@FreeBSD.ORG Fri Nov 16 00:22:13 2007 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id EAF7216A46D for ; Fri, 16 Nov 2007 00:22:12 +0000 (UTC) (envelope-from andre@freebsd.org) Received: from c00l3r.networx.ch (c00l3r.networx.ch [62.48.2.2]) by mx1.freebsd.org (Postfix) with ESMTP id 4C7AA13C502 for ; Fri, 16 Nov 2007 00:22:12 +0000 (UTC) (envelope-from andre@freebsd.org) Received: (qmail 67072 invoked from network); 15 Nov 2007 23:56:20 -0000 Received: from c00l3r.networx.ch (HELO [127.0.0.1]) ([62.48.2.2]) (envelope-sender ) by c00l3r.networx.ch (qmail-ldap-1.03) with SMTP for ; 15 Nov 2007 23:56:20 -0000 Message-ID: <473CE2B9.8010201@freebsd.org> Date: Fri, 16 Nov 2007 01:22:17 +0100 From: Andre Oppermann User-Agent: Thunderbird 1.5.0.13 (Windows/20070809) MIME-Version: 1.0 To: Scott Ullrich References: <200711151729.lAFHTbiq024351@ambrisko.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-net@freebsd.org, freebsd-current@freebsd.org, Julian Elischer , "Wilkinson, Alex" , Jack Vogel Subject: Re: I/OAT ... Coming Soon ? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Nov 2007 00:22:13 -0000 Scott Ullrich wrote: > On 11/15/07, Doug Ambrisko wrote: >> Hmm, I forgot about the 2970 which are AMD based. Can you check the >> BIOS to see if there is an option to turn it on? I think this is an >> Intel feature. AMD might have something close? We have one 2970 >> that we've played with a little but not much. I can't say for sure >> if it has it. > > Right you are. As of BIOS 1.2.2 I do not see a I/OAT option. Guess > I will need to pick up a different server as we are interested in what > kind of packet forwarding rate increase that this feature might bring > on a heavily loaded firewall. Not much. Unless your firewall is in usermode. Otherwise the data stays in the kernel and I/OAT is of not help as no copying happens. Your CPU is probably spending half of its clock cycles waiting on cache misses from newly arrived packets. Some Intel chipset integrated gige ports have a cache prefetch feature (duno whether our driver supports it) that would help quite a bit for your case. -- Andre