From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 36EC77F37 for ; Mon, 11 Mar 2013 17:19:41 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay2.corp.sgi.com (Postfix) with ESMTP id 10DE1304059 for ; Mon, 11 Mar 2013 15:19:40 -0700 (PDT) Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by cuda.sgi.com with ESMTP id 29XdECiWGi6qccM2 for ; Mon, 11 Mar 2013 15:19:38 -0700 (PDT) Date: Tue, 12 Mar 2013 09:19:36 +1100 From: Dave Chinner Subject: Re: Maximum file system size of XFS? Message-ID: <20130311221936.GD21651@dastard> References: <20130309215121.0e614ef8@thinky> <201303112245.40522.Martin@lichtvoll.de> <201303112257.00798.Martin@lichtvoll.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <201303112257.00798.Martin@lichtvoll.de> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Martin Steigerwald Cc: Pascal , xfs@oss.sgi.com On Mon, Mar 11, 2013 at 10:57:00PM +0100, Martin Steigerwald wrote: > Am Montag, 11. M=E4rz 2013 schrieb Martin Steigerwald: > > 2) Create a insanely big sparse file > > = > > merkaba:~> truncate -s1E /mnt/zeit/evenmorecrazy.img > > merkaba:~> ls -lh /mnt/zeit/evenmorecrazy.img > > -rw-r--r-- 1 root root 1,0E M=E4r 11 22:37 /mnt/zeit/evenmorecrazy.img > > = > > (No, this won=B4t work with Ext4.) > = > Okay, you can=B4t go beyond 8 EiB for a single file which is about what I= have = > read somewhere: Right - file size offsets max out at 2^63 bytes. .... > merkaba:/mnt/zeit#5> vgcreate --physicalextentsize 4G justinsane /dev/lo= op0 = > /dev/loop1 > Volume group "justinsane" successfully created > = > merkaba:/mnt/zeit> vgs = = > VG #PV #LV #SN Attr VSize VFree = > justinsane 2 0 0 wz--n- 14,00e 14,00e > merkaba 1 4 0 wz--n- 278,99g 4,85g > merkaba:/mnt/zeit> .... > Enough insanity for today :) > = > I won=B4t mkfs.xfs on it, the 20 GiB of the just filesystem wouldn=B4t be = > enough. Right - I did a mkfs.xfs on a (8EB - 1GB) file a couple of days ago just to check it worked. I killed it after a short while, because I didn't feel like needlessly subjecting the SSDs the file was physically located on to the 25 million sparse sector sized writes needed for mkfs to complete. And you can double that number of writes needed for a 16EB filesystem to be initialised by mkfs. So, theory be damned, even mkfs.xfs doesn't scale to supporting exabyte filesystems... Cheers, Dave. -- = Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs