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 n4D042Gl104106 for ; Tue, 12 May 2009 19:04:02 -0500 Received: from mail.sandeen.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id D63B01D11AA8 for ; Tue, 12 May 2009 17:04:08 -0700 (PDT) Received: from mail.sandeen.net (sandeen.net [209.173.210.139]) by cuda.sgi.com with ESMTP id Z45FbIhCPhz9KbVq for ; Tue, 12 May 2009 17:04:08 -0700 (PDT) Message-ID: <4A0A0E76.6000701@sandeen.net> Date: Tue, 12 May 2009 19:04:06 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: file preallocation without unwritten flag being set References: <283244.29270.qm@web65608.mail.ac4.yahoo.com> In-Reply-To: <283244.29270.qm@web65608.mail.ac4.yahoo.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 Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: p v Cc: xfs@oss.sgi.com p v wrote: > > Hello, > > I need to create large files fast without initializing them - in the > past I used these steps - > > mkfs -t xfs -f -d unwritten=0 /dev/sda1 mount -t xfs -o noatime > /dev/sda1 /hay touch /hay/foo xfs_io /hay/foo xfs_io> resvsp 0 1024g > xfs_io> quit ls -i /hay/foo 131 /hay/foo umount /hay xfs_db -x > /dev/sda1 xfs_db> inode 131 xfs_db> write core.size 1099511627776 > core.size = 1099511627776 xfs_db> q Is there a reason that you don't want the unwritten flag set? (You know that not using the unwritten extents feature exposes garbage from the disk in this case?) There may well be a legit reason but I just want to make sure you're doing what you think you're doing :) Thanks, -Eric > But unwritten=0 is failing as unrecognized option now (was it > deprecated????) so I tried to clear the unwritten extent flag > directly - > > xfs_db> a u.bmbt.ptrs[1] xfs_db> write recs[1].extentflag 0 > recs[1].extentflag = 1 xfs_db> > > It just won't change to 0 - any way to do this? Or is there any > straightforward way to preallocate a large file and set it's file > size without the unwritten flags being turned on? > > Thanks > > Peter Vajgel > > > > > > _______________________________________________ xfs mailing list > xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs > _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs