From: Alex Tomas Subject: Re: [RFC][Patch 2/2] Persistent preallocation in ext4 Date: Fri, 22 Dec 2006 18:31:03 +0300 Message-ID: References: <20061205134338.GA1894@amitarora.in.ibm.com> <20061215123920.GB24572@amitarora.in.ibm.com> <20061219114251.GA25086@amitarora.in.ibm.com> <20061219211409.GP5937@schatzie.adilger.int> <20061222151615.GA5851@amitarora.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Andreas Dilger , linux-ext4@vger.kernel.org, suparna@in.ibm.com, cmm@us.ibm.com, suzuki@in.ibm.com, alex@clusterfs.com Return-path: Received: from ppp85-141-214-150.pppoe.mtu-net.ru ([85.141.214.150]:51273 "EHLO gw.home.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S965204AbWLVQKG (ORCPT ); Fri, 22 Dec 2006 11:10:06 -0500 To: "Amit K. Arora" In-Reply-To: <20061222151615.GA5851@amitarora.in.ibm.com> (Amit K. Arora's message of "Fri\, 22 Dec 2006 20\:46\:15 +0530") Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org >>>>> Amit K Arora (AKA) writes: AKA> Above we can see that block numbers from 68 to 502 are each covered by AKA> more than one extent (besides couple of holes, which also might be part AKA> of the same problem). AKA> Note: A "u" in extent[u] donates that this extent is AKA> uninitialized, and thus was created as part of preallocation and noone AKA> has written to it. An "i" signifies that the extent is initialized. AKA> I am trying to solve this issue currently. Any suggestions are more than AKA> welcome.. :) I'd write a simple function that check given leaf for consistency (in this case you need to check that every subsequent extent doesn't overlap previous one) and add this check in few points (before and after change). this worked very well, especially if all extents fit single block. thanks, Alex