Multirate: A Flexible MPI Benchmark for Fast Assessment of Multithreaded Communication Performance

As the modern hardware landscape continues to drastically change, the degree of parallelism required to maintain a high occupancy of resources has substantially increased. These hardware changes have highlighted the limitations of the traditional method of using one process per processing unit, which indicates that a more flexible programming paradigm is necessary. In the context of the message passing paradigm, MPI needs a significant improvement in threaded performance in order to fully utilize all hardware capabilities. However, for developers to know what needs to be improved, and for users to know what performance to expect, benchmarks are needed to quickly assess the capabilities and performance of MPI implementations. This paper introduces a new communication benchmark designed to replicate typical application communication patterns and assess their performance with a varied amount of resources. We evaluate three MPI implementations with our benchmark suite and assess their strengths and weaknesses.