[Mpi3-rma] RMA synchronization optimization [was: Updated MPI-3 RMA proposal 1]

[Pavan Balaji]

Hi Doug,

On 06/23/2010 08:01 AM, Douglas Miller wrote:
> Right, the amount of code to maintain does increase, especially in the case
> that nothing is deprecated. My concern is for the performance of "common
> use" cases, which I think are where only one synchronization mode is used
> (is this not true? are there any "real" codes using this?).

 From your description it is (somewhat) clear that the code complexity 
does increase, but to me it's not clear that it becomes more 
inefficient. Why does the possibility that an RMA operation might happen 
sometime later make it more inefficient?

They way the MPI standard is structured is that RMA operations can 
happen anytime between Win_create/alloc and Win_free, which seems like 
an "epoch" in terms of your expectation.

  -- Pavan

-- 
Pavan Balaji
http://www.mcs.anl.gov/~balaji