[pnfs] pNFS testing at connectathon

[Iyer, Rahul]

> 
> >We will work on trying to make sure we don't do this, 
> however, I do not 
> >believe it is illegal for a client to issue more than one 
> LAYOUTGET for 
> >the same file and byte range; at least the spec doesn't outlaw this.
> >  
> >
> If a client issues a LAYOUTGET for a file and byte range that 
> it already has a layout for, the files based server should 
> just reply to the LAYOUTGET request with the layout that has 
> already been handed out.  
> Correct?
Yes. That's the interpretation we're going with.

> 
> As far as what was happening at Bakeathon (just from memory)...
> 
> I think the root cause of why our server was returning 
> NFS4ERR_LAYOUTTRYLATER to you was that upon receipt of the 
> LAYOUTGET from your client, we would record that a layout was 
> requested for the the file and byte range specified and then 
> we would contact all of the data servers included in the 
> layout.  When doing this, we hung trying to contact one of 
> the data servers and couldn't respond to the LAYOUTGET.  
> Then, I believe the LAYOUTGET request was retransmitted by 
> your client and that is when we responded with NFS4ERR_LAYOUTTRYLATER.
> 
> We (well actually Robert Gordon) are changing our server side 
> LAYOUTGET processing so I don't think we'll see this error at 
> Connectathon.
Cool! So I hope we can interoperate this time around!
Regards
Rahul