Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759550Ab0FJQZV (ORCPT ); Thu, 10 Jun 2010 12:25:21 -0400 Received: from 0122700014.0.fullrate.dk ([95.166.99.235]:60558 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751996Ab0FJQZU (ORCPT ); Thu, 10 Jun 2010 12:25:20 -0400 Message-ID: <4C1111ED.6020008@fusionio.com> Date: Thu, 10 Jun 2010 18:25:17 +0200 From: Jens Axboe MIME-Version: 1.0 To: Linus Torvalds CC: "linux-kernel@vger.kernel.org" , Christoph Hellwig Subject: Re: [GIT PULL] block/io bits for 2.6.35-rc References: <4C10EC2A.8060002@fusionio.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1735 Lines: 38 On 2010-06-10 17:55, Linus Torvalds wrote: > On Thu, Jun 10, 2010 at 6:44 AM, Jens Axboe wrote: >> >> - A set of patches fixing the WB_SYNC_NONE writeback from Christoph. So >> we should finally have both functional and working WB_SYNC_NONE from >> umount context. > > I _really_ think this is too late, considering how broken it has been. > We already reverted the WB_SYNC_NONE things exactly because it didn't > work, didn't we? I'm going to be off-line in two days, and this part > of the pull request really makes me nervous, if only simply because of > the history of it all (ie it's always been broken, why shouldn't it be > broken now?). > > IOW, that's a lot of scary changes, that have historically not been > safe or sufficiently tested, and have caused problems for various > filesystems. Convince me why they should suddenly be ok to merge? I agree, it's late and it makes me nervous too. I had them cook for a day, didn't see any problems. And Christoph would not send it in unless it passes at least xfs qa, which is what found the problems last time (the ones we reverted). It's fixing a regression where umount takes a LONG time if you have a lot of dirty inodes, since it basically degenerates to a data integrity writeback instead of a simple WB_SYNC_NONE. If it wasn't fixing a nasty regression (the distros are all wanting a real fix for this, it's a user problem), I would not be submitting this code at this point in time. -- Jens Axboe -- 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/