From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id C9E997F4E for ; Mon, 25 Aug 2014 17:34:40 -0500 (CDT) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay1.corp.sgi.com (Postfix) with ESMTP id B5AAC8F804B for ; Mon, 25 Aug 2014 15:34:40 -0700 (PDT) Received: from ipmail04.adl6.internode.on.net (ipmail04.adl6.internode.on.net [150.101.137.141]) by cuda.sgi.com with ESMTP id hwJVf01hvTumwDXr for ; Mon, 25 Aug 2014 15:34:38 -0700 (PDT) Date: Tue, 26 Aug 2014 08:34:31 +1000 From: Dave Chinner Subject: Re: [PATCH] xfs: trim eofblocks before collapse range Message-ID: <20140825223431.GG20518@dastard> References: <1408988250-17772-1-git-send-email-bfoster@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1408988250-17772-1-git-send-email-bfoster@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Brian Foster Cc: xfs@oss.sgi.com On Mon, Aug 25, 2014 at 01:37:30PM -0400, Brian Foster wrote: > xfs_collapse_file_space() currently writes back the entire file > undergoing collapse range to settle things down for the extent shift > algorithm. While this prevents changes to the extent list during the > collapse operation, the writeback itself is not enough to prevent > unnecessary collapse failures. > > The current shift algorithm uses the extent index to iterate the in-core > extent list. If a post-eof delalloc extent persists after the writeback > (e.g., a prior zero range op where the end of the range aligns with eof > can separate the post-eof blocks such that they are not written back and > converted), xfs_bmap_shift_extents() becomes confused over the encoded > br_startblock value and fails the collapse. > > As with the full writeback, this is a temporary fix until the algorithm > is improved to cope with a volatile extent list and avoid attempts to > shift post-eof extents. > > Signed-off-by: Brian Foster > --- > > Hi all, > > This addresses the other fsx failure I've observed related to collapse > range. It should also be addressed by reworking the algorithm as > discussed in Dave's full file writeback patch. This patch applies on top > of that and I think this is more suitable for a near-term -rc drop. Added to my set of patches for testing. Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs