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Measure MPI (mmpi)

This implements a simple MPI program which measures the amount of time it takes to send fixed length MPI messages from every MPI process to every other MPI process. The resulting message delivery times are plotted for a variety of cores. The resulting plots, showing both delivery time and variability in delivery times, between MPI ranks often show how the message delivery times change as the MPI send them off-processor, or off-node.

Dependencies

This program is primarily C language program. The post-processing scripts however, include a matlab plotting script, developed when a matlab license was avialable. These plots should be re-implemented as matplotlib scripts, to increase the portability of the program.

ToDo

These scripts, especially the post-processing scripts that extract the timing information from log files, need to be modified for new systems. The script must be modified to extract the information as written by the system under test. These script can be improved if more general purpose log file parser was developed.

Also, these timing information is collected in one direction. However, the resulting timing plots show symmetry around the axis. These plots should be updated to collect bi-directional data. Plotting of the bi-directional data should remove duplicate measurements that lead to the symmetric plots.