From owner-freebsd-stable@FreeBSD.ORG Wed Oct 14 12:51:23 2009 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 69CCA106566C for ; Wed, 14 Oct 2009 12:51:23 +0000 (UTC) (envelope-from luigi@onelab2.iet.unipi.it) Received: from onelab2.iet.unipi.it (onelab2.iet.unipi.it [131.114.59.238]) by mx1.freebsd.org (Postfix) with ESMTP id 2C1818FC15 for ; Wed, 14 Oct 2009 12:51:22 +0000 (UTC) Received: by onelab2.iet.unipi.it (Postfix, from userid 275) id CD93F730DA; Wed, 14 Oct 2009 14:58:16 +0200 (CEST) Date: Wed, 14 Oct 2009 14:58:16 +0200 From: Luigi Rizzo To: Thomas Backman Message-ID: <20091014125816.GB42021@onelab2.iet.unipi.it> References: <20091012223529.GA77733@onelab2.iet.unipi.it> <3C775420-9B3D-4971-BDA8-4D2FD507587F@exscape.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3C775420-9B3D-4971-BDA8-4D2FD507587F@exscape.org> User-Agent: Mutt/1.4.2.3i Cc: freebsd-stable Subject: Re: Extreme console latency during disk IO (8.0-RC1, previous releases also affected according to others) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 Oct 2009 12:51:23 -0000 On Tue, Oct 13, 2009 at 09:58:09AM +0200, Thomas Backman wrote: > > On Oct 13, 2009, at 12:35 AM, Luigi Rizzo wrote: ... > >hi, > >this issue (not specific to FreeBSD, and not new -- it has been > >like this forever) is discussed in some detail here > > > > http://www.bsdcan.org/2009/schedule/events/122.en.html > > > >The following code (a bit outdated) can help > > > >http://lists.freebsd.org/pipermail/freebsd-stable/2009-March/048704.html > > > >cheers > >luigi > Hmm, how stable would you say the code is? (And/or has there been any > progress since March?) > I'd prefer something that I feel confident in using in production, and > the warning in the README clearly says "stay away!". Maybe not for production but if you want to use it on a test box to see if it helps then it is definitely reliable (as long as you don't exercise too much the plugging and unplugging schedulers on a mounted filesystems). I have been using the code for perhaps a couple of months on my desktop machine and no data loss, the only reason it is not loaded now is that it is not loaded by default at boot time. cheers luigi