[zeromq-dev] Non-contiguous message thoughts

[Brian Granger]

Martin,

>> I haven't been able to follow this thread very closely, but I do have
>> one question:
>>
>> You can already do non-copying sends of non-contiguous memory using
>> 0MQ, you just have to send multiple messages.  What additional benefit
>> would message groups give beyond that?
>
> It's atomicity. Imagine load-balancing socket such as ZMQ_DOWNSTREAM. If
> there are two peers connected and you send 2 messages, one message will go
> to one peer while the second goes to the another.

This makes perfect sense and would be a great addition - especially if
it works with all the socket types.

> Also, you don't want 0MQ to deliver 1st part of the message while remaining
> parts are not yet available. That kind of thing can possibly cause
> deadlocks.

OK, this was the other aspect part I was wondering.  So will you be
guaranteed that if 1 message from the group arrives that all will
arrive?

Cheers,

Brian

> Martin
>



-- 
Brian E. Granger, Ph.D.
Assistant Professor of Physics
Cal Poly State University, San Luis Obispo
bgranger at calpoly.edu
ellisonbg at gmail.com