Benchmarking mpich


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The mpich/examples/perftest directory contains a sophisticated tool for measuring latency and bandwidth for mpich on your system. To run it, first make sure that mpich was configured with the -mpe option. Then go to mpich/examples/perftest and do

    make 

    mpirun -np 2 mpptest -gnuplot > out.gpl 

The file out.gpl will then contain the necessary gnuplot commands. The file mppout.gpl will contain the data. To view the data with gnuplot, use:
    gnuplot out.gpl 

or use
    load 'out.gpl' 

from within gnuplot. Depending on your environment and version of gnuplot, you may need to start gnuplot first and issue the command set terminal x11 before executing load 'out.gpl'.

The programs mpptest and goptest have a wide variety of capabilities; the option -help will list them. For example, mpptest can automatically pick message lengths to discover any sudden changes in behavior and can investigate the ability to overlap communication with computation. These programs are written using MPI, and may be used with any MPI implementation, not just mpich. (See the configure file in the examples/perftest directory.) More information is available at http://www.mcs.anl.gov/mpi/mpptest.

Benchmarking can be very tricky. See http://www.mcs.anl.gov/mpi/mpptest/hownot.html for some common benchmarking errors. The paper [11] discusses these issues at more length.



Up: Contents Next: The mpich Programming Environment Previous: Internationalization