On 06/05/2010 10:54 AM, Underwood, Keith D wrote:

Yeah, (4) exists, but I didn't list it because, as you observe, (2) is the analogue of it and is "the MPI way".

I listed (4) because we didn't decide in the previous meeting whether to go with (2) or (4).

We would need to think about whether we have to have the whole message ordered or ordered on a per target address basis.

Atomicity and ordering go hand-in-hand; if there's no atomicity, ordering doesn't make sense. Since we have basic datatype atomicity for accumulate/get_accumulate, ordering would make sense at that granularity as well. If someone wants to propose full-message atomicity, then we can consider ordering at that granularity too. But till then, whole message ordering is an overkill. -- Pavan -- Pavan Balaji http://www.mcs.anl.gov/~balaji