From owner-freebsd-net@FreeBSD.ORG Wed Jul 4 08:13:09 2012 Return-Path: Delivered-To: net@freebsd.org Received: from mx2.freebsd.org (mx2.freebsd.org [IPv6:2001:4f8:fff6::35]) by hub.freebsd.org (Postfix) with ESMTP id AAB5F106566B; Wed, 4 Jul 2012 08:13:09 +0000 (UTC) (envelope-from dougb@FreeBSD.org) Received: from opti.dougb.net (hub.freebsd.org [IPv6:2001:4f8:fff6::36]) by mx2.freebsd.org (Postfix) with ESMTP id 2DCB81512BF; Wed, 4 Jul 2012 08:13:09 +0000 (UTC) Message-ID: <4FF3FB14.8020006@FreeBSD.org> Date: Wed, 04 Jul 2012 01:13:08 -0700 From: Doug Barton Organization: http://SupersetSolutions.com/ User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:13.0) Gecko/20120621 Thunderbird/13.0.1 MIME-Version: 1.0 To: "Alexander V. Chernikov" References: <4FF319A2.6070905@FreeBSD.org> <4FF361CA.4000506@FreeBSD.org> <20120703214419.GC92445@onelab2.iet.unipi.it> <4FF36438.2030902@FreeBSD.org> <4FF3E2C4.7050701@FreeBSD.org> In-Reply-To: <4FF3E2C4.7050701@FreeBSD.org> X-Enigmail-Version: 1.4.2 OpenPGP: id=1A1ABC84 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: net@freebsd.org Subject: Re: FreeBSD 10G forwarding performance @Intel 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: Wed, 04 Jul 2012 08:13:09 -0000 On 07/03/2012 23:29, Alexander V. Chernikov wrote: > On 04.07.2012 01:29, Doug Barton wrote: >>>> Just curious ... what's the MTU on your FreeBSD box, and the Linux box? > > In this particular setup - 1500. You're probably meaning type of mbufs > which are allocated by ixgbe driver? 1500 for both? And no, I'm not thinking of the mbufs directly, although that may be a side effect. I've seen cases on FreeBSD with em where setting the MTU to 9000 had unexpected (albeit pleasant) side effects on throughput vs. system load. Since it was working better I didn't take the time to find out why. However since you're obviously interested in finding out the nitty-gritty details (and thank you for that) you might want to give it a look, and a few test runs. hth, Doug -- This .signature sanitized for your protection