Duane,
I believe Paul is talking about
a new, second, sequence that is used as a
rollover for the first sequence - not
reusing the original sequence. If the
second sequence could preserve the InOrder-ness
(assuming that is the DA
needed) across sequences then I believe
it should work. The question is
whether or not this type of logic is
something the spec should help support
or leave it up to the source to deal
with it on its own.
thanks,
-Doug
Duane Nickull <>
07/18/2005 11:35 AM
To
Paul Fremantle <>
cc
Jacques Durand <>,
"'Patil, Sanjay'" <>, ,
Christopher B Ferris/Waltham/IBM@IBMUS, Doug Davis/Raleigh/IBM@IBMUS,
Subject
Re: [ws-rx] NEW ISSUE: Sequence
termination on Fault
Paul:
I am a bit confused. Rolling over a message sequence number and
preserving the original sequence does absolutely nothing to reclaim
resources or mitigate the problem of superseding the destinations
capabilities.
Assume for example that the rollover was at 1000 and message 1001 is now
the new 0001. In order to facilitate reliable messaging, the
destination still has to preserve all 1000 of the original message plus
reconcile message 0001 as message 1001, not have duplicate message
0001's in the sequence. Since the messaging component of the stack
is
relatively dumb and will get its instructions for things like rolling
back transactions form the application/business layer, it cannot release
the first 1000 messages since the upper stack logic may dictate that if
message 1003 is not received in XX minutes, the entire sequence should
roll back to message 934. Accordingly, it must persist all messages
in
the sequence or throw an unrecoverable fault.
The rollover is currently an unrecoverable fault and nothing more.
That is how it is written in the current draft.
Did I miss something? Please correct me if I did.
Thanks
Duane Nickull
Paul Fremantle wrote:
>I think Jacques' points about handling the rollover problem "smoothly"
are
>key. I would like to see an explicit sequence take-over model that
can be
>used to preserve ordering across sequences where one sequence has ended
-
>prematurely from the RM sources perspective.
>
>
>
>
