Estimating Communication Rates in MPI

RING_MPI is a C++ program which estimates the time it takes to send a vector of N double precision values through each process in a ring.

Process 0 sends N double precision values to process 1, which passes them to process 2, and so on, until process P-1 sends them back to process 0. The time for this transmission is recorded. The experiment is repeated several times, and for several different array sizes N.

The latest versions of MPI no longer support the special C++ MPI bindings, so the examples given here have reverted to using the C MPI bindings.


The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.


RING_MPI is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version.

Related Data and Programs:

COMMUNICATOR_MPI, a C++ program which creates new communicators involving a subset of initial set of MPI processes in the default communicator MPI_COMM_WORLD.

HEAT_MPI, a C++ program which solves the 1D Time Dependent Heat Equation using MPI.

HELLO_MPI, a C++ program which prints out "Hello, world!" using MPI for parallel execution.

MPI, C++ programs which illustrate the use of the MPI application program interface for carrying out parallel computatioins in a distributed memory environment.

MPI_STUBS, a C++ library which contains stub MPI routines, allowing a user to compile, load, and possibly run an MPI program on a serial machine.

MULTITASK_MPI, a C++ program which demonstrates how to "multitask", that is, to execute several unrelated and distinct tasks simultaneously, using MPI for parallel execution.

PRIME_MPI, a C++ program which counts the number of primes between 1 and N, using MPI for parallel execution.

QUAD_MPI, a C++ program which approximates an integral using a quadrature rule, and carries out the computation in parallel using MPI.

RANDOM_MPI, a C++ program which demonstrates one way to generate the same sequence of random numbers for both sequential execution and parallel execution under MPI.

SATISFY_MPI, a C++ program which demonstrates, for a particular circuit, an exhaustive search for solutions of the circuit satisfiability problem, using MPI to carry out the calculation in parallel.

SEARCH_MPI, a C++ program which searches integers between A and B for a value J such that F(J) = C, using MPI for parallel execution.

WAVE_MPI, a C++ program which uses finite differences and MPI to estimate a solution to the wave equation.


  1. Peter Pacheco,
    Parallel Programming with MPI,
    Morgan Kaufman, 1996,
    ISBN: 1558603395,
    LC: QA76.642.P3.

Source Code:

Examples and Tests:

RING_FSU compiles and runs the program on the FSU HPC cluster.

RING_LOCAL compiles and runs the program on the local system, which might work if OpenMPI is installed, and which might make sense if your system has multiple cores.

You can go up one level to the C++ source codes.

Last revised on 20 October 2012.