From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Barton Date: Tue, 12 Feb 2008 19:43:44 +0000 Subject: [Lustre-devel] Lustre HSM HLD draft In-Reply-To: <20080212172321.GQ3029@webber.adilger.int> References: <47AAE307.9040305@cea.fr> <47ACC71C.7050808@sun.com> <47B062BA.1070809@cea.fr> <47B0B0FF.7060805@sun.com> <20080212035557.GP3029@webber.adilger.int> <026801c86d67$01a0beb0$0281a8c0@ebpc> <47B1BA52.8040304@cea.fr> <20080212172321.GQ3029@webber.adilger.int> Message-ID: <032701c86daf$94333f30$0281a8c0@ebpc> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org Andreas, Is this requirement documented? I'd appreciate any pointers... > -----Original Message----- > From: Andreas.Dilger at Sun.COM [mailto:Andreas.Dilger at Sun.COM] > On Behalf Of Andreas Dilger > Sent: 12 February 2008 5:23 PM > To: Aurelien Degremont > Cc: Eric Barton; lustre-devel at lists.lustre.org > Subject: Re: [Lustre-devel] Lustre HSM HLD draft > > On Feb 12, 2008 16:25 +0100, Aurelien Degremont wrote: > > Eric Barton a ?crit : > > > Sorry if these questions duplicates previous debate. > > > > > > Have I understood correctly that the design allows > individual objects > > > within a lustre file (i.e. stripes?) to be purged independently? > > > > > > If so why is this needed? > > > > > > I would have thought that when you purge a file, you need > only record > > > the purged extent as an attribute of the whole lustre > file and punch > > > its stripes to free the space. Am I missing a use case? > > > > Since the beginning CFS required this feature. It seems a > lab ask for > > it. I do not know who. Unfortunately we have no use case > for what they > > want to do with this. > > I'm wondering if their need could not be met with other > features like > > the internal Lustre migration... > > That is my understanding also - I believe one of the Labs wanted this > (to be able to do HSM on a per-stripe basis instead of a > per-file basis). > > Cheers, Andreas > -- > Andreas Dilger > Sr. Staff Engineer, Lustre Group > Sun Microsystems of Canada, Inc. > >