> From: 'J. Bruce Fields' [mailto:bfields@xxxxxxxxxxxx] > Sent: Friday, March 8, 2019 1:38 PM > To: Frank Filz <ffilzlnx@xxxxxxxxxxxxxx> > Cc: 'linux-fsdevel' <linux-fsdevel@xxxxxxxxxxxxxxx>; > Volker.Lendecke@xxxxxxxxx; samba-technical@xxxxxxxxxxxxxxx; 'Jeremy Allison' > <jra@xxxxxxxxx>; 'Linux NFS Mailing List' <linux-nfs@xxxxxxxxxxxxxxx>; 'Jeff > Layton' <jlayton@xxxxxxxxxx>; 'Amir Goldstein' <amir73il@xxxxxxxxx>; > devel@xxxxxxxxxxxxxxxxxxxxx; 'Ralph Boehme' <slow@xxxxxxxxx> > Subject: [NFS-Ganesha-Devel] Re: Better interop for NFS/SMB file share > mode/reservation > > On Wed, Mar 06, 2019 at 07:37:00AM -0800, Frank Filz wrote: > > > On Wed, Mar 06, 2019 at 09:09:21AM +0200, Amir Goldstein wrote: > > > > On Tue, Mar 5, 2019 at 11:48 PM J. Bruce Fields > > > > <bfields@xxxxxxxxxxxx> wrote: > > > > > > > > > > On Thu, Feb 14, 2019 at 04:06:52PM -0500, J. Bruce Fields wrote: > > > > > > After this: > > > > > > > > > > > > https://marc.info/?l=linux-nfs&m=154966239918297&w=2 > > > > > > > > > > > > delegations would no longer conflict with opens from the same > > > > > > tgid. So if your threads all run in the same process and > > > > > > you're willing to manage conflicts among your own clients, > > > > > > that should still allow you to do multiple opens of the same > > > > > > file without giving up your > > > lease/delegation. > > > > > > > > > > > > I'd be curious to know whether that works with Samba's design. > > > > > > > > > > Any idea whether that would work? > > > > > > > > > > (Easy? Impossible? Possible, but realistically the changes > > > > > required to Samba would be painful enough that it'd be unlikely > > > > > to get done?) > > > > > > > > > > > > > [CC Ralph Boehme] > > > > > > > > I am not a samba team member, but seems to me that your proposal > > > > fits samba design like a glove. With one smbd process per client > > > > connection, with your proposal, opens (for read) from same smbd > > > > process will not break the shared read lease from same client, so > > > > oplocks level II could be implemented using kernel oplocks (new > > > > flavor). > > > > > > OK. So I wonder about Ganesha. I'm not sure, but I *think* it's > > > like knfsd in that it has a bunch of worker threads that can each > > > take rpc's from any client. I don't remember if they're actually > > > threads or processes. > > > > Ganesha does use worker threads > > And they're all part of one process? Sorry, should have specified, yes, Ganesha runs a single multi-threaded process. > > however, one thing that may be an > > advantage here, or at least can be leveraged, is that Ganesha attaches > > a single file descriptor to each stateid. As long as the I/O requests > > come using the stateid, that file descriptor will be used. > > > > We have some work completed and more in progress on delegations, and > > if there becomes a new kernel oplock available, we could definitely > > use it. On the other hand, FSAL_VFS which is the FSAL used with kernel > > file systems does not support delegations... > > > > The (distributed) file systems we support delegations on have use > > space libraries (which Samba should also be using?) that implement the > > delegation primitives. > > Is there anyone working on delegation support for FSAL_VFS? If it's not getting > much attention then maybe Samba is the only real user for the forseeable > future. As far as I know, no one is working on delegations for FSAL_VFS. A good interface would make it something that might be used if it then became easy to implement delegations. FSAL_VFS is convenient for verifying some of the protocol and meta-data caching features of Ganesha. Frank
