Green HPC: MPI vs. OpenMP on a shared memory system

A power consumption of a high performance computer (HPC) system has been an issue lately. Many programming techniques are still relying on performance gain, but only few of them are concerning energy footprint of the increased computing power. MPI and OpenMP are considered as a core scientific HPC programming libraries for distributed-memory and shared-memory computer systems respectively. Each of them brings performance when used on a parallel system, but there are dissimilarities in their performance per watt ratio. The key is to find the best appliance for each of them on a shared-memory computer system.