OpenMPI+ Java as a High Performance Language

The Message Passing Interface (MPI) is a software platform that can utilize the parallel capabilities of most multi-processors, making it useful for teaching students about parallel and distributed computing (PDC). MPI provides language bindings for Fortran and C/C++, but many university instructors lack expertise in these languages, preventing them from using MPI in their courses. OpenMPI is a free implementation of MPI that also provides Java bindings, allowing instructors who know Java but not C/C++ or Fortran to teach PDC. However, Java has a reputation as a “slow” language, so some say it is unsuitable for teaching PDC. This paper gives a head-to-head comparison of the performance of OpenMPI's Java and C bindings. Our study shows that by default, Java can be faster than C unless one takes special measures, and it exhibits similar speedup, efficiency, and scalability. We conclude that Java is a suitable language for teaching PDC.