Methods, apparatus, and products are disclosed for performance testing of message passing operations in a parallel computer, the parallel computer comprising a plurality of compute nodes organized into at least one operational group, that include: establishing, on a compute node of the operational group, a number of measurement iterations for testing a message passing operation, a first group of the measurement iterations designated as warm-up iterations, and a second group of the measurement iterations designated as testing iterations; for each measurement iteration: executing, by the compute node, the message passing operation under test, and measuring, by the compute node, an elapsed time for only the execution of the message passing operation under test; and determining, by the compute node, a performance result in dependence upon the elapsed time for each measurement iteration designated as one of the testing iterations.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with Government support under Contract No. B554331 awarded by the Department of Energy. The Government has certain rights in this invention.