Selection of message passing collectives in presence of system noise
Consideration of system jitter in selecting a “message passing collectives algorithm” used in a message passing interface. A set of multiple message passing collectives algorithms are ranked against each other with at least some consideration of relative jitter-related performance as between the algorithms. The consideration of jitter includes consideration of “system jitter” (OS jitter and/or network jitter). In some embodiments, multiple rankings are performed for different levels of system jitter.
1. A computer program product comprising:
a machine readable storage device; and
computer code stored on the machine readable storage device, with the computer code including instructions for causing a processor(s) set to perform operations including the following:
providing a plurality of message passing collectives algorithms,
evaluating each algorithm of the plurality of message passing collectives algorithms for performance when subject to at least one type(s) of jitter to obtain jitter evaluations, ranking the plurality of message passing collectives algorithms relative to each other based upon the jitter evaluations to obtain a first ranking,
selecting, at runtime, a first message passing collectives algorithm from the plurality of message passing collectives algorithm, where the selection is based, at least in part, on the first ranking,
performing message passing using the first message passing collectives algorithm, and
estimating a level of system jitter that will occur at runtime through performance data collected by benchmarks during offline calibration to obtain an estimated system jitter level,
wherein:
the selection of the first message passing collectives algorithms is further based, at least in part, upon a first non-jitter factor which is not related to any type of jitter, and
the at least one type(s) of jitter includes both of the following types of jitter: operating system jitter and/or network jitter.