From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q15HNDcR056550 for ; Sun, 5 Feb 2012 11:23:14 -0600 Received: from enyo.dsw2k3.info (enyo.dsw2k3.info [195.71.86.239]) by cuda.sgi.com with ESMTP id YFdIFk25w5vHD6bY (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Sun, 05 Feb 2012 09:23:12 -0800 (PST) Date: Sun, 5 Feb 2012 18:23:02 +0100 From: Matthias Schniedermeyer Subject: Re: sparsify - utility to punch out blocks of 0s in a file Message-ID: <20120205172302.GA7057@citd.de> References: <4F2D8F30.3090802@redhat.com> <201202050933.q159XQpB026380@helium.internal.tigress.co.uk> <4F2EB017.5090006@redhat.com> <9C5B5C07-B0E4-4D13-BCFE-7F35162DF5E8@dilger.ca> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <9C5B5C07-B0E4-4D13-BCFE-7F35162DF5E8@dilger.ca> 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: Andreas Dilger Cc: Eric Sandeen , "linux-ext4@vger.kernel.org" , Ron Yorston , "xfs@oss.sgi.com" On 05.02.2012 09:55, Andreas Dilger wrote: > > Matthias' suggestion of adding SEEK_HOLE/SEEK_DATA makes very good sense too. > > I thought about this, but if SEEK_HOLE/SEEK_DATA (or FIEMAP) worked, then the file would already be sparse, so I don't think that will help in this case... With that argumentation you wouldn't need the tool in the first place. "How can a bunch of zeros be in a file in the first place?" "Can only be because of the deficiency of another program." And who is to say that you wouldn't want to repeat such a thing from time to time, without SEEK_HOLE/SEEK_DATE you MAY crunch through big regions of zeros for no gain at all. Bis denn -- Real Programmers consider "what you see is what you get" to be just as bad a concept in Text Editors as it is in women. No, the Real Programmer wants a "you asked for it, you got it" text editor -- complicated, cryptic, powerful, unforgiving, dangerous. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs