From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751940AbZHaW0m (ORCPT ); Mon, 31 Aug 2009 18:26:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751558AbZHaW0m (ORCPT ); Mon, 31 Aug 2009 18:26:42 -0400 Received: from mail-gx0-f205.google.com ([209.85.217.205]:44686 "EHLO mail-gx0-f205.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929AbZHaW0l convert rfc822-to-8bit (ORCPT ); Mon, 31 Aug 2009 18:26:41 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=JNIxXdTCcZHlBALMlufqUF71xOnLz1ydNEQnhjXcBbwyiYU7JDT5AFpZGDvBIv82FH QD7Hff9IcHRvZAZr+7yHn9btKGe6QTqxyhdkSIMZt2nz5fDJyv5rnUtlJySvxAqsUtjN 0P/g/JnGRRszaFZ4ODalL34aZwVNvnqjaJ7TM= MIME-Version: 1.0 In-Reply-To: <20090831180746.GA32110@piper.oerlikon.madduck.net> References: <4A947682.2010204@redhat.com> <4A967175.5070700@redhat.com> <20090827221319.GA1601@ucw.cz> <4A9733C1.2070904@redhat.com> <20090828064449.GA27528@elf.ucw.cz> <20090828120854.GA8153@mit.edu> <20090830075135.GA1874@ucw.cz> <20090830152023.GB23828@mit.edu> <4807377b0908311049id9a2167r937bc8447c2b3546@mail.gmail.com> <20090831180746.GA32110@piper.oerlikon.madduck.net> Date: Mon, 31 Aug 2009 15:26:42 -0700 Message-ID: <4807377b0908311526r3b42f581j27b9c26166b7ac96@mail.gmail.com> Subject: Re: raid is dangerous but that's secret (was Re: [patch] ext2/3: document conditions when reliable operation is possible) From: Jesse Brandeburg To: Jesse Brandeburg , Theodore Tso , Pavel Machek , NeilBrown , Ric Wheeler , Rob Landley , Florian Weimer , Goswin von Brederlow , kernel list , Andrew Morton , mtk.manpages@gmail.com, rdunlap@xenotime.net, linux-doc@vger.kernel.org, linux-ext4@vger.kernel.org, corbet@lwn.net Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 31, 2009 at 11:07 AM, martin f krafft wrote: > also sprach Jesse Brandeburg [2009.08.31.1949 +0200]: >> In the case of a degraded array, could the kernel be more >> proactive (or maybe even mdadm) and have the filesystem remount >> itself withOUT journalling enabled?  This seems on the surface to >> be possible, but I don't know the internal particulars that might >> prevent/allow it. > > Why would I want to disable the filesystem journal in that case? I misspoke w.r.t journalling, the idea I was trying to get across was to remount with -o sync while running on a degraded array, but given some of the other comments in this thread I'm not even sure that would help. the idea was to make writes as safe as possible (at the cost of speed) when running on a degraded array, and to have the transition be as hands-free as possible, just have the kernel (or mdadm) by default remount. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Brandeburg Subject: Re: raid is dangerous but that's secret (was Re: [patch] ext2/3: document conditions when reliable operation is possible) Date: Mon, 31 Aug 2009 15:26:42 -0700 Message-ID: <4807377b0908311526r3b42f581j27b9c26166b7ac96@mail.gmail.com> References: <4A947682.2010204@redhat.com> <4A967175.5070700@redhat.com> <20090827221319.GA1601@ucw.cz> <4A9733C1.2070904@redhat.com> <20090828064449.GA27528@elf.ucw.cz> <20090828120854.GA8153@mit.edu> <20090830075135.GA1874@ucw.cz> <20090830152023.GB23828@mit.edu> <4807377b0908311049id9a2167r937bc8447c2b3546@mail.gmail.com> <20090831180746.GA32110@piper.oerlikon.madduck.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE To: Jesse Brandeburg , Theodore Tso , Pavel Machek , NeilBrown , Ric Wheeler , Rob Landley Received: from mail-gx0-f205.google.com ([209.85.217.205]:44686 "EHLO mail-gx0-f205.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750929AbZHaW0l convert rfc822-to-8bit (ORCPT ); Mon, 31 Aug 2009 18:26:41 -0400 In-Reply-To: <20090831180746.GA32110@piper.oerlikon.madduck.net> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Aug 31, 2009 at 11:07 AM, martin f krafft w= rote: > also sprach Jesse Brandeburg [2009.08.31= =2E1949 +0200]: >> In the case of a degraded array, could the kernel be more >> proactive (or maybe even mdadm) and have the filesystem remount >> itself withOUT journalling enabled? =A0This seems on the surface to >> be possible, but I don't know the internal particulars that might >> prevent/allow it. > > Why would I want to disable the filesystem journal in that case? I misspoke w.r.t journalling, the idea I was trying to get across was to remount with -o sync while running on a degraded array, but given some of the other comments in this thread I'm not even sure that would help. the idea was to make writes as safe as possible (at the cost of speed) when running on a degraded array, and to have the transition be as hands-free as possible, just have the kernel (or mdadm) by default remount. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html