Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1767694AbXEDG5l (ORCPT ); Fri, 4 May 2007 02:57:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1767700AbXEDG5i (ORCPT ); Fri, 4 May 2007 02:57:38 -0400 Received: from mail.chehov.net ([80.71.245.247]:58526 "EHLO mail.rialcom.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1767694AbXEDG53 (ORCPT ); Fri, 4 May 2007 02:57:29 -0400 X-Spam-Flag: SKIP X-Spam-Yversion: Spamooborona 1.6.1 Message-ID: <463AD948.9090103@clusterfs.com> Date: Fri, 04 May 2007 10:57:12 +0400 From: Alex Tomas Organization: Cluster Filesystems, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.10) Gecko/20070302 Fedora/1.5.0.10-1.fc6 pango-text Thunderbird/1.5.0.10 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Andrew Morton CC: Andreas Dilger , Linus Torvalds , Marat Buharov , Mike Galbraith , LKML , Jens Axboe , "linux-ext4@vger.kernel.org" Subject: Re: [ext3][kernels >= 2.6.20.7 at least] KDE going comatose when FS is under heavy write load (massive starvation) References: <1177660767.6567.41.camel@Homer.simpson.net> <20070427013350.d0d7ac38.akpm@linux-foundation.org> <698310e10704270459t7663d39dp977cf055b8db9d2a@mail.gmail.com> <20070427193130.GD5967@schatzie.adilger.int> <20070427151837.f1439639.akpm@linux-foundation.org> <463A1E02.8020506@clusterfs.com> <20070503165428.855eb7d7.akpm@linux-foundation.org> <463AD024.6060208@clusterfs.com> <20070503233804.9dace4a7.akpm@linux-foundation.org> In-Reply-To: <20070503233804.9dace4a7.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1543 Lines: 49 Andrew Morton wrote: > On Fri, 04 May 2007 10:18:12 +0400 Alex Tomas wrote: > >> Andrew Morton wrote: >>> Yes, there can be issues with needing to allocate journal space within the >>> context of a commit. But >> no-no, this isn't required. we only need to mark pages/blocks within >> transaction, otherwise race is possible when we allocate blocks in transaction, >> then transacton starts to commit, then we mark pages/blocks to be flushed >> before commit. > > I don't understand. Can you please describe the race in more detail? if I understood your idea right, then in data=ordered mode, commit thread writes all dirty mapped blocks before real commit. say, we have two threads: t1 is a thread doing flushing and t2 is a commit thread t1 t2 find dirty inode I find some dirty unallocated blocks journal_start() allocate blocks attach them to I journal_stop() going to commit find inode I dirty do NOT find these blocks because they're allocated only, but pages/bhs aren't mapped to them start commit map pages/bhs to just allocate blocks so, either we mark pages/bhs someway within journal_start()--journal_stop() or commit thread should do lookup for all dirty pages. the latter doesn't sound nice, IMHO. thanks, Alex - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/