Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752879AbWLWJ1Y (ORCPT ); Sat, 23 Dec 2006 04:27:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752872AbWLWJ1Y (ORCPT ); Sat, 23 Dec 2006 04:27:24 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:50947 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752789AbWLWJ1X (ORCPT ); Sat, 23 Dec 2006 04:27:23 -0500 Date: Sat, 23 Dec 2006 09:27:18 +0000 From: Christoph Hellwig To: David Chinner Cc: Alex Tomas , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC] delayed allocation for ext4 Message-ID: <20061223092718.GA26276@infradead.org> Mail-Followup-To: Christoph Hellwig , David Chinner , Alex Tomas , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org References: <20061223033123.GL44411608@melbourne.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061223033123.GL44411608@melbourne.sgi.com> User-Agent: Mutt/1.4.2.2i X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1218 Lines: 24 On Sat, Dec 23, 2006 at 02:31:23PM +1100, David Chinner wrote: > > - ext4-delayed-allocation.patch > > delayed allocation itself, enabled by "delalloc" mount option. > > extents support is also required. currently it works only > > with blocksize=pagesize. > > Ah, that's why you can get away with a page flag - you've ignored > the partial page delay state problem. Any plans to use the > existing method in the future so we will be able to use ext4 delalloc > on machines with a page size larger than 4k? I think fixing this up for blocksize < pagesize is an absolute requirement to get things merged. We don't need more filesystems that are crippled on half of our platforms. Note that recording delayed alloc state at a page granularity in addition to just the buffer heads has a lot of advantages aswell and would help xfs, too. But I think it makes a lot more sense to record it as a radix tree tag to speed up the gang lookups for delalloc conversion. - 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/