From owner-freebsd-net@FreeBSD.ORG Thu Apr 28 07:30:28 2011 Return-Path: <owner-freebsd-net@FreeBSD.ORG> 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 2A8C6106564A for <freebsd-net@freebsd.org>; Thu, 28 Apr 2011 07:30:28 +0000 (UTC) (envelope-from kungfujesus06@gmail.com) Received: from mail-iy0-f182.google.com (mail-iy0-f182.google.com [209.85.210.182]) by mx1.freebsd.org (Postfix) with ESMTP id E302D8FC1B for <freebsd-net@freebsd.org>; Thu, 28 Apr 2011 07:30:27 +0000 (UTC) Received: by iyj12 with SMTP id 12so2814858iyj.13 for <freebsd-net@freebsd.org>; Thu, 28 Apr 2011 00:30:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:date:from:to:subject:message-id:mime-version :content-type:content-disposition:user-agent; bh=G1Kee/6QvVql18mhNLTWMjL07yCZEAynsdsWPUyil8U=; b=PS1W8ocxJEgMlQhe+J0+xKPc3EX48CA7aQ9DBknJGwNccjyyy7SQjor6MF/nD0BIVC nwyF+HRsCEnS3DnHIeVyD0zqu9w5qa14cDwl0fsHmFrUgJ2KQH9NRBkPULydb/dr9OSd Q0xqsTBbPVX9cB+ADlC+oNz9KT4ntAeBS3e/k= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:subject:message-id:mime-version:content-type :content-disposition:user-agent; b=pV80Mh8r5ofs5seWp3ZTpxV987WdslCD+o9SZo/XSgw7r7017fLliuXQiBbFVxcOqN exeAzPs5Lr8Sfld5MXTACXEtzqWaNC4ssqrh9nTDOFYlfdfhPD4FbZimnN16Wo+/iHDW 1LrczUP9n8VS9FboX6vdPA8lSvGV8mSdoVcFo= Received: by 10.42.157.199 with SMTP id e7mr4057430icx.278.1303975827170; Thu, 28 Apr 2011 00:30:27 -0700 (PDT) Received: from zephyr.adamsnet ([72.49.234.31]) by mx.google.com with ESMTPS id y10sm622249iba.12.2011.04.28.00.30.25 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 28 Apr 2011 00:30:26 -0700 (PDT) Date: Thu, 28 Apr 2011 03:29:46 -0400 From: Adam Stylinski <kungfujesus06@gmail.com> To: freebsd-net@freebsd.org Message-ID: <20110428072946.GA11391@zephyr.adamsnet> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="qDbXVdCdHGoSgWSk" Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Subject: em0 performance subpar X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>, <mailto:freebsd-net-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net> List-Post: <mailto:freebsd-net@freebsd.org> List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>, <mailto:freebsd-net-request@freebsd.org?subject=subscribe> X-List-Received-Date: Thu, 28 Apr 2011 07:30:28 -0000 --qDbXVdCdHGoSgWSk Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, I have an intel gigabit network adapter (the 1000 GT w/chipset 82541PI) whi= ch performs poorly in Freebsd compared to the same card in Linux. I've tri= ed this card in two different freebsd boxes and for whatever reason I get p= oor transmit performance. I've done all of the tweaking specified in just = about every guide out there (the usual TCP window scaling, larger nmbcluste= rs, delayed acks, etc) and still I get only around 600mbps. I'm using jumb= o frames, with an MTU of 9000. I'm testing this with iperf. While I reali= ze that this may not be the most realistic test, linux hosts with the same = card can achieve 995Mbit/s to another host running this. When the Freebsd = box is the server, Linux hosts can transmit to it at around 800 something M= bit/s. I've increased the transmit descriptors as specified in the if_em m= an page, and while that gave me 20 or 30 more mbit/s, my transmit performan= ce is still below normal. =20 sysctl stats report that the card is trigger a lot of tx_desc_fail2: dev.em.0.tx_desc_fail2: 3431 Looking at a comment in the source code this indicates that the card was no= t able to obtain enough transmit descriptors (but I've given the card the m= aximum of 4096 in my loader.conf tunable). Is this a bug or a performance = regression of some kind? Does anybody have a fix for this? I tried anothe= r card with the same chip in a different box on 8-STABLE to no avail (the b= ox I'm trying to improve performance on is on 8.2-RELEASE-p1). Anybody manage to make this card push above 600mbps in ideal network benchm= arks? Any help would be gladly appreciated. --=20 Adam Stylinski PGP Key: http://pohl.ececs.uc.edu/~adam/publickey.pub Blog: http://technicallyliving.blogspot.com --qDbXVdCdHGoSgWSk Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (FreeBSD) iQIcBAEBAgAGBQJNuRdpAAoJED6sRHE6TvmnhSwP/RncWw07PGrukndXs+/VVDLa SBPC8V1GUUW3zoisNEKORYQQ4qYM97Ql94zNB11tFR9MxjcmqJjZv2GqmVSiMGHR 5px/UOuoQjiGYxcFfqVyaN6EhaZaSGLmiYlVfNdSAFYwZ1jNcl1AsmD+zKgl6BRw UfmVui8UlmmakggQJ2qir2yr+6cmi6VV6MCaJNelHnVJ7ggHB85Qha1UdaoFqb2e UzDsAMnU6RDeEhQxvRvlv+ch0cAciTnVm/ipmR+5PQEJ4Wht4rhjTEodK/IZ8O/Z fEYapcS11HTZal6T4FMjImB3bf0YpT2tV//H5SycGDsGUNgNysbOBnuP/rway7x0 Qhp5XR1gKW7YNCzREe9dK7QtmUIcjHIFw9/qSWt4tRaEerpDR8sH9JUq71Hvc2QC pws9SHFBzYjV4zKZg597TJuuSY0gWPKpRZmPmY3mZ0aR0LnbVQgO29ay0lgCuyxF owhdUUb5JKmn9H7vcOacTQYYP//GyWMMYnVMmDCecz5jOWAQuN5xx4htQKhDu1I5 bV3qG1+j2F6iIEP+7DKWogIEF3QcbF3vecboeehc5MouoIpEyLm6jyA3GQnW/gE4 RNuqKVuoMFgqK06QdBNNgysNkfj3oY4WrkDPoNAJFvE2PYeIZxFzr7Cve5Cm+Bgt 8lL3b3dFM7OkIzx5CUAh =hke5 -----END PGP SIGNATURE----- --qDbXVdCdHGoSgWSk--