From owner-freebsd-current@FreeBSD.ORG Thu Nov 1 15:25:18 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 8552716A420 for ; Thu, 1 Nov 2007 15:25:18 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from speedfactory.net (mail6.speedfactory.net [66.23.216.219]) by mx1.freebsd.org (Postfix) with ESMTP id 2D8DC13C4B0 for ; Thu, 1 Nov 2007 15:25:17 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (unverified [66.23.211.162]) by speedfactory.net (SurgeMail 3.8p) with ESMTP id 217264608-1834499 for multiple; Thu, 01 Nov 2007 10:24:02 -0500 Received: from localhost.corp.yahoo.com (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.13.8/8.13.8) with ESMTP id lA1FNpfe006973; Thu, 1 Nov 2007 11:23:51 -0400 (EDT) (envelope-from jhb@freebsd.org) From: John Baldwin To: "Jack Vogel" Date: Thu, 1 Nov 2007 11:21:15 -0400 User-Agent: KMail/1.9.6 References: <20071011003619.GA84433@obelix.dsto.defence.gov.au> <200710312232.l9VMWgJJ090112@lava.sentex.ca> <2a41acea0710311544x5db98f27ta0f1276fd06d13f@mail.gmail.com> In-Reply-To: <2a41acea0710311544x5db98f27ta0f1276fd06d13f@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200711011121.15687.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Thu, 01 Nov 2007 11:23:51 -0400 (EDT) X-Virus-Scanned: ClamAV 0.91.2/4658/Thu Nov 1 08:50:49 2007 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: freebsd-current@freebsd.org, Mike Tancsa Subject: Re: em0: watchdog timeout ... 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: Thu, 01 Nov 2007 15:25:18 -0000 On Wednesday 31 October 2007 06:44:36 pm Jack Vogel wrote: > On 10/31/07, Mike Tancsa wrote: > > At 06:25 PM 10/31/2007, Jack Vogel wrote: > > > > > > > > > >What if you use MSI? > > > > > > > > How do I enable that ? > > > > > >sysctl hw.pci.enable_msi=1 > > > > > >and > > > > > >sysctl hw.pci.enable_msix=1 > > > > > >For those that don't know, MSI/X is there in STABLE but off by default. > > > > Thanks, > > Do I need to do this in /boot/loader.conf or can I set it at > > any time? Are there any performance hits / boosts to use this method > > instead of the default ? > > I have set it after the system booted and it seemed to work. > > John could speak more authoritatively since he wrote it, but I have > seen no problem turning em use on whenever. Uh, this means of > course, enabling it and THEN loading the driver, if em is loaded and > you enable the system it will have no effect on em until unload and > reloading it. > > John has also said that MSI in 6.X is not as full an implementation as > in 7 but I don't recall what that amounted to. > > It means you have a unique unshared interrupt, I have never really had > any performance tests done on MSI vs Legacy so I can't speak to that. The only thing MSI in 6.x doesn't have is the MSI-X remap function, the rest of the implementation is identical. I just haven't enabled it by default on 6.x due to caution. -- John Baldwin