From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id BB77D7FD6 for ; Wed, 10 Apr 2013 15:31:57 -0500 (CDT) Message-ID: <5165CC39.2090108@sgi.com> Date: Wed, 10 Apr 2013 15:31:53 -0500 From: Mark Tinguely MIME-Version: 1.0 Subject: Re: [PATCH] xfs: reserve fields in inode for parent ptr and alloc policy References: <20130410182438.268267840@sgi.com> <5165B5CB.2070203@sandeen.net> <5165BFF4.8020601@sgi.com> In-Reply-To: <5165BFF4.8020601@sgi.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Rich Johnston Cc: Eric Sandeen , xfs@oss.sgi.com On 04/10/13 14:39, Rich Johnston wrote: > On 04/10/2013 01:56 PM, Eric Sandeen wrote: >> On 4/10/13 1:24 PM, Mark Tinguely wrote: >>> Reserve fields in new inode layout for parent pointer and >>> allocation policy. >>> ---- >>> The inode will hold the parent information for the first >>> link to a file. Information for the other links will be >>> held in extended attribute entries. >>> >>> The "di_parino" is the inode of the parent directory. The >>> directory information for this entry is located the parent >>> directory with "di_paroff" offset. >>> >>> The di_parino/di_paroff concept code is running. >>> ---- >>> The "di_allocpolicy" will be used to remember the allocation >>> policy associated with this inode. >> >> can you say more about this allocation policy? >> >> -Eric > > No its super secret information. ;) > > Its on my plate Eric, because Mark was making a change for parent ptrs, > I asked him to request space for allocation policies also. > > I don't have all the details yet but here is a very high level concept. > > Identify allocation groups by names (or numbers -- preferably using names > in user-visible areas), allowing many different areas. Placing the > allocation > policy outside of user programs is necessary for this to be successful. > > Current thoughts on proposed a layered allocation policies: > > Policy for the entire filesystem > Policy attached to a directory (whose policy would be inherited by > subdirectories when subdirectories are created) > Policy for a single file > > The policy would define: > > where to place file data > where to place metadata for the files. > a prefered allocation group for placing file data (for directories). > > --Rich > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs The allocation policies is based on work by Dave: http://oss.sgi.com/archives/xfs/2009-02/msg00250.html --Mark. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs