From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e7.ny.us.ibm.com ([32.97.182.137]:45808 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751322Ab2JCBAe (ORCPT ); Tue, 2 Oct 2012 21:00:34 -0400 Received: from /spool/local by e7.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 2 Oct 2012 21:00:33 -0400 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay03.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q9310Uad126844 for ; Tue, 2 Oct 2012 21:00:30 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q9310UT7015600 for ; Tue, 2 Oct 2012 21:00:30 -0400 Message-ID: <506B8E2C.7070107@linux.vnet.ibm.com> Date: Tue, 02 Oct 2012 18:00:28 -0700 From: Wade Cline MIME-Version: 1.0 To: Josef Bacik CC: linux-btrfs@vger.kernel.org, "cmm@linux.vnet.ibm.com" Subject: Re: [RFC] [PATCH] Btrfs: rework can_nocow_odirect References: <1349118014-6319-1-git-send-email-jbacik@fusionio.com> In-Reply-To: <1349118014-6319-1-git-send-email-jbacik@fusionio.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi Josef, This patch is causing fragmentation with O_DIRECT on preallocated extents located -after- the first write to the preallocated extent. This happens regardless of nodatacow/autodefrag mount options. Thank you, Wade On 10/01/2012 12:00 PM, Josef Bacik wrote: > I need everybody to go over this with a fine toothed comb since it is a pretty > big change. I think it is right and it seems to come out right, but if it's not > it will mean we screw up O_DIRECT on snapshotted files with preallocated > extents, so please, make sure it is correct :).