ask-MPI

This program retrieves some information about MPI library using MPI calls:

• List of the ranks, hostnames, PIDs and CWDs of all threads.
• The MPI standard version supported by the MPI library.
• The current level of thread support.
• The upper bound for MPI tags. It may vary wildly values from 2¹⁹-1 to 2³¹-1 have been seen.
• The information from MPI_INFO_ENV
• The MPI library build information.

When compiled with defined symbol MPI41 it also tries to decode:

• The info object returned by MPI_Get_hw_resource_info.

Compilation

You can do just

mpif90 ask_mpi.F90 && ./a.out && rm a.out

or something more elaborate such as adding -D MPI41 (for the newest MPI versions) or -fc=ifx if it is needed by your Intel's OneAPI environment.

Legacy MPI

On old MPI/compiler environments, where the use mpi_f08 does not work please switch to non_mpi_f08 branch to be able to compile the test.