[pnfs] [PATCH 9/9] pnfs client prevent race in sequence slot

[Trond Myklebust]

On Thu, 2007-09-27 at 22:54 +0200, Benny Halevy wrote:

> The problem with doing this is that you might be racing with the 
> original call in case it
> was delayed in the network for some obscure reason and you could get 
> MISORDERED or DELAY
> on the retry.  In the DELAY case you'll need to poll the server until it 
> finishes processing the previous
> request, then you should get MISORDERED again and you can try seq#+1 yet 
> again.

You should never get a NFS4ERR_SEQ_MISORDERED error since you are
retrying a sequenceid that is known to be either the next free
sequenceid or the current in-use one. You should therefore get either
NFS4ERR_DELAY or NFS4ERR_SEQ_FALSE_RETRY. Both those errors are obvious
to recover from...

Cheers
  Trond