From owner-freebsd-stable@FreeBSD.ORG Sat Jul 16 14:07:42 2005 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 56BE816A41C for ; Sat, 16 Jul 2005 14:07:42 +0000 (GMT) (envelope-from mkb@mkbuelow.net) Received: from luzifer.incubus.de (incubus.de [80.237.207.83]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8845343D55 for ; Sat, 16 Jul 2005 14:07:41 +0000 (GMT) (envelope-from mkb@mkbuelow.net) Received: from drjekyll.mkbuelow.net (p54AA8609.dip0.t-ipconnect.de [84.170.134.9]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by luzifer.incubus.de (Postfix) with ESMTP id 399FD327FC for ; Sat, 16 Jul 2005 16:10:33 +0200 (CEST) Received: from drjekyll.mkbuelow.net (mkb@localhost.mkbuelow.net [127.0.0.1]) by drjekyll.mkbuelow.net (8.13.3/8.13.3) with ESMTP id j6GE7s6A000791 for ; Sat, 16 Jul 2005 16:07:54 +0200 (CEST) (envelope-from mkb@drjekyll.mkbuelow.net) Received: (from mkb@localhost) by drjekyll.mkbuelow.net (8.13.3/8.13.3/Submit) id j6GE7son000790 for freebsd-stable@freebsd.org; Sat, 16 Jul 2005 16:07:54 +0200 (CEST) (envelope-from mkb) Date: Sat, 16 Jul 2005 16:07:54 +0200 From: Matthias Buelow To: freebsd-stable@freebsd.org Message-ID: <20050716140754.GA752@drjekyll.mkbuelow.net> References: <20050715224650.GA48516@outcold.yadt.co.uk> <200507152342.j6FNg5Tx015427@drjekyll.mkbuelow.net> <20050716101657.GA44786@pc5.i.0x5.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050716101657.GA44786@pc5.i.0x5.de> User-Agent: Mutt/1.4.2.1i Subject: Re: dangerous situation with shutdown process 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: Sat, 16 Jul 2005 14:07:42 -0000 Nicolas Rachinsky wrote: >> >The track which is corrupted could contain data that wasn't written >> >to in months. How would the journal help? >> >> I don't understand this question. > >The track destroyed could contain sectors which are in no way related >to the sectors the OS is writing to. And in what way is that related to the existence or nonexistence of write barriers and a journal? If you pound the disk with a hammer, it will most likely break, no matter what strategy you're using. That you cannot eliminate _all_ sources of error with a strategy doesn't mean that you shouldn't implement it to minimize the number of errors that could happen. Besides, I always thought that (most) disks had enough power reserve to be able to write at least one track when power goes away? Or is that an urban myth, I don't know for sure. mkb.