What controls does Open MPI have that aid in debugging?
Open MPI has a series of MCA parameters for the MPI layer itself that are designed to help with debugging. These parameters can be can be set in the usual ways. MPI-level MCA parameters can be displayed by invoking the following command: shell$ ompi_info –param mpi all Here is a summary of the debugging parameters for the MPI layer: • mpi_param_check: If set to true (any positive value), and when Open MPI is compiled with parameter checking enabled (the default), the parameters to each MPI function can be passed through a series of correctness checks. Problems such as passing illegal values (e.g., NULL or MPI_DATATYPE_NULL or other “bad” values) will be discovered at run time and an MPI exception will be invoked (the default of which is to print a short message and abort the entire MPI job). If set to 0, these checks are disabled, slightly increasing performance. • mpi_show_handle_leaks: If set to true (any positive value), OMPI will display lists of any MPI handles that were not free
