From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Mon, 07 May 2007 22:03:13 -0700 (PDT) Received: from sandeen.net (sandeen.net [209.173.210.139]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id l48539fB010772 for ; Mon, 7 May 2007 22:03:10 -0700 Message-ID: <4640048B.6070803@sandeen.net> Date: Tue, 08 May 2007 00:03:07 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: RESVSP problems References: <200705072004.22848.lucke@o2.pl> <463F7368.8090101@sandeen.net> <200705072058.32679.lucke@o2.pl> <20070508005923.GS77450368@melbourne.sgi.com> In-Reply-To: <20070508005923.GS77450368@melbourne.sgi.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: David Chinner Cc: =?UTF-8?B?xYF1a2FzeiBGaWJpbmdlcg==?= , xfs@oss.sgi.com David Chinner wrote: >>> yeah... ISTR that the arguments are funky. I can't remember if it's a >>> bug or not. :) FWIW, allocsp just writes zeros to the file, so you >>> could do it just as well from userspace w/ no fancy ioctls... ALLOCSP >>> is a bit pointless if you ask me... though maybe someone knows why it's >>> there :) >> Let me say that I have noticed that using ALLOCSP seems to create less extents >> than posix_fallocate/manual zeroing. > > Yes, that's likely ;) > > There's work currently active to make posix_fallocate() do the same thing > as ALLOCSP (i.e. call into the filesystem and let it do smart stuff), but > that's a ways off yet... Dave, doesn't ALLOCSP actually create actual zeroed space though? Pretty much as posix_fallocate from userspace does today, maybe with better allocation... And "smart stuff" would be *not* needing to write zeros.... i.e. what RESVSP does. -Eric