Introduction to Sun MPI

The MPI specification was developed by the MPI Forum, a group of software developers, computer vendors, academics, and computer-science researchers whose goal was to develop a standard for writing message-passing programs that would be efficient, flexible, and portable.

The outcome, known as the MPI Standard, was first published in 1993. The most recent version (MPI-2) was published in 1997. It was well received, and several implementations are available publicly.

Sun MPI is a complete library of message-passing routines, including all MPI 1.2-compliant and MPI 2-compliant routines. Chapter 2 provides an overview of the routines, Appendix A summarizes them, and the Sun man pages provide detailed descriptions.

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Sun MPI Features

• Optimization for running with Sun HPC ClusterTools 5 software using C, C⁺⁺, Fortran 77, or Fortran 90.
• Integration with the Sun HPC ClusterTools Runtime Environment (CRE) and the Sun GridEngine, LSF, and PBS distributed resource-management systems.
• Support for multithreaded programming.
• Seamless use of various network protocols.
• Multiprotocol support so that MPI selects the fastest available medium for each type of connection (such as shared memory, RSM, and ATM).
• Communication by shared memory for fast performance on clusters of SMPs
• Finely tunable shared-memory communication.
• Optimized collectives for symmetric multiprocessors (SMPs) and clusters of SMPs.
• MPI I/O support for parallel file I/O.
• Prism support, so that users can develop, run, and debug programs in the Prism programming environment.
• Implicit co-scheduling, whereby the Sun HPC spind daemon enables certain processes of a given MPI job on a shared-memory system to be scheduled at approximately the same time as other related processes. This co-scheduling reduces the load on the processors, thus reducing the effect that MPI jobs have on each other.
• Complete support of one-sided communication routines and name-publishing routines.
• Dynamic library support.
• MPI-2 dynamic support.

Sun MPI and MPI I/O provide full F77, C, and C⁺⁺ support, as well as Basic F90 support.

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Sun MPI I/O

File I/O in Sun MPI uses MPI 2-compliant routines for parallel file I/O. Chapter 4 describes these routines. Their man pages are provided online, and the routines are summarized in Appendix A.