From owner-freebsd-current@FreeBSD.ORG Fri Sep 15 10:22:39 2006 Return-Path: X-Original-To: current@FreeBSD.org Delivered-To: freebsd-current@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 06DD616A40F; Fri, 15 Sep 2006 10:22:39 +0000 (UTC) (envelope-from glebius@FreeBSD.org) Received: from cell.sick.ru (cell.sick.ru [217.72.144.68]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2D13B43D45; Fri, 15 Sep 2006 10:22:37 +0000 (GMT) (envelope-from glebius@FreeBSD.org) Received: from cell.sick.ru (glebius@localhost [127.0.0.1]) by cell.sick.ru (8.13.4/8.13.3) with ESMTP id k8FAMUuB078965 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 15 Sep 2006 14:22:30 +0400 (MSD) (envelope-from glebius@FreeBSD.org) Received: (from glebius@localhost) by cell.sick.ru (8.13.4/8.13.1/Submit) id k8FAMSwO078964; Fri, 15 Sep 2006 14:22:28 +0400 (MSD) (envelope-from glebius@FreeBSD.org) X-Authentication-Warning: cell.sick.ru: glebius set sender to glebius@FreeBSD.org using -f Date: Fri, 15 Sep 2006 14:22:28 +0400 From: Gleb Smirnoff To: Brooks Davis Message-ID: <20060915102228.GK27667@FreeBSD.org> References: <7.0.1.0.0.20060912125903.15bdb7a0@sentex.net> <45073F58.6080900@freebsd.org> <200609131108.45382.jhb@freebsd.org> <20060913154622.GA52716@lor.one-eyed-alien.net> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <20060913154622.GA52716@lor.one-eyed-alien.net> User-Agent: Mutt/1.5.6i Cc: Andre Oppermann , current@FreeBSD.org, John Baldwin , Mike Tancsa , Ian FREISLICH , freebsd-current@FreeBSD.org, Jack Vogel Subject: Re: TSO, SMP and the em driver. 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, 15 Sep 2006 10:22:39 -0000 On Wed, Sep 13, 2006 at 10:46:22AM -0500, Brooks Davis wrote: B> On Wed, Sep 13, 2006 at 11:08:44AM -0400, John Baldwin wrote: B> > On Tuesday 12 September 2006 19:14, Andre Oppermann wrote: B> > > Mike Tancsa wrote: B> > > > At 12:43 PM 9/12/2006, Andre Oppermann wrote: B> > > > B> > > >> TSO != (vlan && promisc) B> > > > B> > > > Sorry, the commonality I was referring to was VLAN hardware tagging and B> > > > how it must be enabled for TSO, but that breaks other things. See a few B> > > > messages ago B> > > > B> > http://lists.freebsd.org/pipermail/freebsd-current/2006-September/065818.html B> > > B> > > I'm sure we can find a workaround for that. B> > B> > Well, you could have the em(4) driver manually handle TSO in software, which B> > is what it does to workaround the VLAN tag problem. (It does VLAN B> > encapsulation in the driver.) While VLAN insertion may be trivial, B> > re-implementing TCP segmentation in the driver might be a good bit less B> > trivial to do. There's not going to be a simple easy workaround for this B> > hardware bug. :( B> B> I'm not sure it's worth worrying about with GbE hardware. Just disable B> TSO in promiscuous mode. Where TSO is going to really matter is 10GbE. B> No supporting TSO in some configurations with GbE doesn't seem like a B> big deal to me. Yes, makeing TSO and promisc mutually exclusive would be fine. -- Totus tuus, Glebius. GLEBIUS-RIPN GLEB-RIPE