From: Dmitry Monakhov Subject: Re: [RFC] do you want jbd2 interface of ext3? Date: Mon, 22 Feb 2010 21:57:18 +0300 Message-ID: <87bpfhyu7l.fsf@openvz.org> References: <20100216164123.b10b00e5.toshi.okajima@jp.fujitsu.com> <20100216185452.GE3153@quack.suse.cz> <4B7BAA70.9070605@jp.fujitsu.com> <20100217164933.GC5337@thunk.org> <4B8219B8.8070207@jp.fujitsu.com> <9B774728-3508-4850-B036-CB0013403DE9@mit.edu> <20100222180246.GA3112@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Tso , "toshi.okajima\@jp.fujitsu.com" , "akpm\@linux-foundation.org" , "adilger\@sun.com" , "linux-ext4\@vger.kernel.org" To: Jan Kara Return-path: Received: from mail-bw0-f209.google.com ([209.85.218.209]:63269 "EHLO mail-bw0-f209.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752995Ab0BVS51 (ORCPT ); Mon, 22 Feb 2010 13:57:27 -0500 Received: by bwz1 with SMTP id 1so312248bwz.21 for ; Mon, 22 Feb 2010 10:57:25 -0800 (PST) In-Reply-To: <20100222180246.GA3112@quack.suse.cz> (Jan Kara's message of "Mon, 22 Feb 2010 21:02:47 +0300") Sender: linux-ext4-owner@vger.kernel.org List-ID: Jan Kara writes: > On Mon 22-02-10 08:55:53, Theodore Tso wrote: >> As for quota --- quite seriously --- if you have mission critical users, >> I'd suggest that they not use quota. Dimitry has been turning up all >> sorts of bugs in the quota subsystem, many of which are just as >> applicable to ext3. The real issue is that quota hasn't received as much >> testing as other file system features --- in any file system, not just >> ext4. > I don't agree with this. I know about quite a few large customers > depending on quotas on their servers and they run on ext3 / reiserfs quite > happily. Dmitry's patches touching the generic code were mostly cleanups, > the fixes were just in the delayed allocation handling but that never > gets executed for ext3 or reiserfs... Stability is relative thing. I's quite depends on usecase. For example after triggering bug on not empty orphan list on ext3_umount i've started full orphan-list management code revision. And both ext3/ext4 appears to be almost broken in case of errors. But nobody seems never catch it in real life. But still at that time i have triggered: 1) non empty orphan list on umount for both (ext3 and ext4) 2) on_disk linked list corruption for both 3) data blocks beyond i_size 4) bit-difference on fsck for both Currently i'm working on fixes. It takes week or so. So at least i'll reduce "project_id quota" spam flow a bit. > I don't say there cannot be bugs and certainly quota code has less > exposure than other more used filesystem parts. But I don't know about > any serious quota issue on ext3 / reiserfs in last two years or so > (except the one that was caused by Dmitry's fixes ;). This time i'll try to give enough test coverage. > > Honza