On 08/03/2017 08:42 PM, Jeff Layton wrote:
On Fri, 2017-05-19 at 11:55 +0530, Soumya Koduri wrote:
Hi,
On 05/18/2017 08:04 PM, Yun-Chih Chen wrote:
Hi, friends:
I'm studying the affect of NFSv4 on Linux. As far as I know, NFS
implemented in Linux kernel supports read delegation but not write
delegation. I wonder if Ganesha implements write delegation? If yes,
can it take effect if accessed by Linux NFS client?
I use the following config file to observe delegation in Ganesha:
EXPORT {
Export_Id = 77;
Path = /e;
Pseudo = /e;
Access_Type = RW;
FSAL {
Name = XFS;
}
Delegations = readwrite;
}
NFSV4 {
Delegations = true;
}
However, I did not see any trace of delegation under various workloads
(example: repeated read [1], repeated write [2]) using tools like
nfstrace or tcpdump. When running in debug mode, I always got the
following in the log file:
ganesha.nfsd-8999[main] display_fsinfo :FSAL :DEBUG : delegations = 0
indicating that delegation was not on.
Is there something wrong with my config file? Or any other clue
regarding NFS delegation? Thanks ( ;
AFAIK except for FSAL_GPFS, other FSALs do not have support for
delegations yet. Also after switching to new extended APIs
(>=nfs-ganesha-2.4), delegations are disabled. It needs some additional
work. We are planning to address it as part of adding this support for
FSAL_GLUSTER (hopefully in 2.6 release). WRT XFS, I am not sure if
anyone is actively looking at it.
Thanks,
Soumya
Hi Soumya,
I just started looking at delegation support in ganesha (mostly with an
eye toward plumbing in delegation support for Ceph).
I think we probably need to rework the whole delegation interface (maybe
even give it a dedicated FSAL op), and was wondering if you had started
any work along those lines.
Hi Jeff,
yes. I started it but have done only POC to mainly test the glusterfs
lease support (which is experimental feature) at first. I could manage
to get leases granted from and returned to the backend.
The only changes I had done so far in the core ganesha layer is to
uncomment earlier delegation code path to get the request all the way
till FSAL [1]. I now intent to fix the SAL layer and happy to
collaborate with you. Agree that instead of clubbing with lock, a
dedicated fop shall be better.
Thanks,
Soumya
[1] https://review.gerrithub.io/372998
Thanks,
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Nfs-ganesha-devel mailing list
Nfs-ganesha-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs-ganesha-devel
