I vote for #2. Hubert ________________________________________ From: [email protected] [[email protected]] on behalf of Jim Dinan [[email protected]] Sent: Wednesday, July 25, 2012 8:45 PM To: [email protected] Subject: Re: [Mpi3-rma] [EXTERNAL] Re: Disp_unit in allocate_shared should be returned by win_shared_query? Hi All, We should try to reach a decision on this issue before the end of the week. I think it would be helpful to hear some other opinions. So far, we have three options to choose from: 1) Require that the displacement unit be the same at all processes for MPI_Win_allocate_shared(). 2) Allow different displacement units at each process in shared memory windows and allow processes to determine the displacement unit at remote processes via MPI_Win_shared_query(). This is in addition to the MPI-2 self-query already possible with MPI_Win_get_attr(MPI_WIN_DISP_UNIT). 3) Allow different displacement units at each process in shared memory windows and provide only the MPI-2 self-query already possible with MPI_Win_get_attr(MPI_WIN_DISP_UNIT). Manual communication would be needed to exchange disp_unit information. A (very) rough summary of the discussion on this issue: * Given that non-uniform disp_unit values are currently allowed, processes may need to use disp_unit in address calculations. * Requiring programmers to use the disp_unit at each process in address calculations diminishes the usefulness of the shared memory programming model. It's also not clear if there is a use case to support the non-uniform disp_unit model. Thanks, ~Jim. _______________________________________________ mpi3-rma mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-rma Click https://www.mailcontrol.com/sr/wycxuHidNhjTndxI!oX7UoEGNNKKZK+evdchg5q1g6rvv... to report this email as spam.