From: Christian Kujau Subject: Re: birth time of a file Date: Thu, 25 Sep 2014 02:40:56 -0700 (PDT) Message-ID: References: <3C36B392-FF09-46D1-B7DA-ADF893A56C42@dilger.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: "linux-ext4@vger.kernel.org" To: Andreas Dilger Return-path: Received: from trent.utfs.org ([94.185.90.103]:41965 "EHLO trent.utfs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751693AbaIYJlI (ORCPT ); Thu, 25 Sep 2014 05:41:08 -0400 In-Reply-To: <3C36B392-FF09-46D1-B7DA-ADF893A56C42@dilger.ca> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, 25 Sep 2014 at 09:08, Andreas Dilger wrote: > It looks like your filesystem is formatted with 128-byte inodes > (i.e. ext3) instead of 256-byte inodes (i.e. ext4). The i_crtime is stored > in this extended space of the inode. You could verify this with Bingo! Thanks, that was the problem. I used a small (less than 512MB) test filesystem and inode size was indeed 128 byte. When I ran mkfs.ext4 on a 512 MB (and larger) device, 256 byte inodes were created and then crtime was indeed visible with debugfs. Or I could have used -I to force larger inodes. Thanks for the hint! Christian. > dumpe2fs -h /dev/loop0 > > and look for the "Inode size" field. > > This is a format time option. What is strange is that you have specified mkfs.ext4, so > this should be selected automatically. It may be that with very small > devices (e.g. floppy size) it defaults to 128-byte inodes. -- BOFH excuse #124: user to computer ration too low.