VOP_LEASE

[Robert Watson]

On Sun, 5 Apr 2009, zachary.loafman at isilon.com wrote:

> On Sun, Apr 05, 2009 at 06:31:59PM +0100, Robert Watson wrote:
>>
>> On Sat, 12 Apr 2008, Jeff Roberson wrote:
>>
>>> As far as I can tell this has never been used.  Unless someone can show me 
>>> otherwise I'm going to go ahead and remove it.
>>
>> (A year, +/- one week, passes...)
>>
>> Since we now have an NFSv4 client/server and it doesn't use VOP_LEASE, and 
>> NQNFS is long-gone, I propose we revisit removing VOP_LEASE [...]
>
> I haven't had a chance to dig into the code, but can you explain how the v4 
> server is granting delegations without something like VOP_LEASE? This was 
> actually a conversation I was going to prep for prior to BSDcan. We already 
> have a cluster-coherent oplock mechanism for CIFS, and we were planning on 
> trying to hook that in with v4 delegations, but our FS very much needs VOP 
> calls to accomplish things like delegations. We can't use a local lease 
> manager.
>
> Like I said, I need to look at code; it's very likely the existing VOP_LEASE 
> isn't right for us, anyways.

Zach,

Let me know if/when you're ready for the VOP_LEASE-axing to take place, and 
I'll move ahead with it.

And we should perhaps add delegation/oplock/etc mechanisms to our agenda for 
the devsummit?

Robert N M Watson
Computer Laboratory
University of Cambridge