From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 980207F50 for ; Fri, 22 Feb 2013 10:17:14 -0600 (CST) Date: Fri, 22 Feb 2013 10:17:13 -0600 From: Ben Myers Subject: Re: inode64 superblock flag is still worth Message-ID: <20130222161713.GV22182@sgi.com> References: <20130222132721.GA10079@andromeda.usersys.redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130222132721.GA10079@andromeda.usersys.redhat.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 Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Carlos Maiolino Cc: xfs@oss.sgi.com Hi Carlos, On Fri, Feb 22, 2013 at 10:27:21AM -0300, Carlos Maiolino wrote: > I was looking the "Ideas for XFS" wiki page, and noticed a topic about the > implementation of a flag in superblock to identify the filesystem is using > 64-bit inodes. Once we use it by default now, is this idea still worth? I can > work on it, but I don't think this is still worth to be implemented. > If still looks worth, I'd suggest a flag set when 32-bit inodes only is used not > 64, but I really dunno how this might be useful for kernel. From a user > perspective, it might help, but `mount` command or mtab already shows inode32 > option when it's used. So the inode32 allocation policy becomes persistent and no longer need to be set at mount time. This is definately worth working on, IMO. Setting a bit in the superblock would work fine for inode32. We should think about something more general before making on-disk changes for this. For example, Rich recently posted the agskip data allocation policy which (like inode32) was implemented as a mount option. If agskip=5 were to be made persistent we'd need space in the superblock to keep track of the 5. I think an xattr on the root inode could be a good solution as long as it is invisible to the user. The interface for changing alloc policies should probably be in xfs_io or xfs_mkfs. -Ben _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs