Hi Junchao, On Oct 14, 2013, at 3:46 PM, Junchao Zhang <[email protected]> wrote:

Hello, I have some questions on MPI_T_init_thread, which are unclear in the Standard. 1) Must MPI_T_init_thread() be called in programs before using MPI_T?

Yes.

2) Must MPI_T_init_thread() be only called by the main thread?

No, I don't think we ever limited that (to allow tools running in other threads).

3) Is it wrong to do MPI_T_init_thread(MPI_THREAD_SINGLE, &provided); MPI_Init_thread(LEVEL_HIGHER_THAN_SINGLE, &provided);

or vice versa,

MPI_Init_thread(MPI_THREAD_SINGLE, &provided); MPI_T_init_thread(LEVEL_HIGHER_THAN_SINGLE, &provided);

No, that should be OK - however, an MPI implementation can choose to return SINGLE from the second calls. Perhaps not the best implementation, but a correct one. Martin

Thanks.

--Junchao Zhang _______________________________________________ mpiwg-tools mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-tools

________________________________________________________________________ Martin Schulz, [email protected], http://people.llnl.gov/schulzm CASC @ Lawrence Livermore National Laboratory, Livermore, USA