A Design of a Communication Library between Multiple Sets of MPI Processes for MPMD

An MPMD programming model is widely used as a master-worker program or a coupling program for multiple physical models. To utilize recent high-end parallel computers having more than several thousand nodes, we propose the communication library MPMPI between different multiple sets of MPI processes in the MPMD model. In particular, we present MPMPI interfaces that include interfaces for a PGAS language and the basic performance of MPMPI functions. As benchmark programs of the MPMPI library, we evaluated the performance of a master-worker program and a weak coupling program. As a result, we found that Pack/Unpack has a large influence on the performance of MPMPI functions, the interface of MPMPI functions can easily be used in these benchmark programs written in Xcalable MP PGAS language, and the performances of the master-worker and weak coupling benchmark programs using the basic MPMPI functions are practical under the conditions of this paper.