A Lightweight C++ Interface to MPI

The Message Passing Interface (MPI) provides bindings for the three programming languages commonly used in High Performance Computing (HPC): C, C++ and Fortran. Unfortunately, MPI supports only the lowest common denominator of the three languages, providing a level of abstraction far lower than typical C++ libraries. Lately, after the decision of the MPI committee to deprecate and remove the C++ bindings from the MPI standard, programmers are forced to use either the C API or rely on third-party libraries. In this paper we present a lightweight, header-only C++ interface to MPI which uses object oriented and generic programming concepts to improve its integration into the C++ programming language. We compare our wrapper with a related approach called Boost. MPI showing how MPP facilitates the interaction with C++ objects. Performance wise, MPP outperforms Boost. MPI by reducing the interface overhead by a factor of eight. Additionally, MPP´s handling of user-defined data types allows transferring of STL containers (e.g. std::list) up to 20 times faster than Boost. MPI for small linked lists by relying on software serialization.