Overview of the MPI Standard and Implementations

The Message Passing Interface (MPI) has become a standard for message passing parallel applications. This report first introduces the underlying paradigm, message passing, and explores some of the challenges explicit message passing poses for developing parallel programs. We then take a closer look at the MPI standardization effort, its goals, and its results to see what features the current version of the MPI standard provides and how MPI became what it is today. Several implementations of the MPI standard, including the open source LAM/MPI and MPICH implementations, and Sun MPI, as an example of a vendor-supplied MPI implementation, are being presented. A comparison is attempted regarding various aspects, such as supported MPI features, system architecture, network hardware, and operating system. Graph-oriented programming (GOP), a high-level abstraction for message passing applications based on MPI, is included as an example of ongoing research that aims to help the developer overcome some of the challenges the low-level approach taken by MPI poses. The report concludes with an outlook on the future of the MPI standard and its implementations, and how they are influenced by current trends in cluster computing.