From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id p585IlCh073924 for ; Wed, 8 Jun 2011 00:18:48 -0500 Received: from ipmail04.adl6.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id AB44616C54CF for ; Tue, 7 Jun 2011 22:18:45 -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 qf794Kjpw1KD4e74 for ; Tue, 07 Jun 2011 22:18:45 -0700 (PDT) Date: Wed, 8 Jun 2011 15:18:42 +1000 From: Dave Chinner Subject: Re: I/O hang, possibly XFS, possibly general Message-ID: <20110608051842.GO32466@dastard> References: <19945.24042.711472.158523@tree.ty.sabi.co.UK> <201106060929.06814@zmi.at> <19950.12549.541440.285348@tree.ty.sabi.co.UK> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <19950.12549.541440.285348@tree.ty.sabi.co.UK> 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 Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Peter Grandi Cc: Michael Monnerie , xfs@oss.sgi.com On Tue, Jun 07, 2011 at 03:09:09PM +0100, Peter Grandi wrote: > Personally I'd rather have a file system design with space > reservations (on detecting an append-like access pattern) and > truncate-on-close than delayed allocation like XFS; Welcome to the 1990s, Peter. XFS has been doing this for 15 years. It is an optimisation used by the delayed allocation mechanism, not a replacement for it. You might have heard the term "speculative preallocation" before - this is what it does. FYI, ext3 has a space reservation infrastructure to try to ensure contiguous allocation occurs without using delayed allocation. It doesn't work nearly as well as delayed allocation in ext4, btrfs or XFS... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs