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DOE OSTI · 1986176

Multi-level parallelization of quantum-chemical calculations

Fedorov, Dmitri G.·Pham, Buu Q.
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Abstract

Here, strategies for multiple-level parallelizations of quantum-mechanical calculations are discussed, with an emphasis on using groups of workers for performing parallel tasks. These parallel programming models can be used for a variety ab initio quantum chemistry approaches, including the fragment molecular orbital method and replica-exchange molecular dynamics. Strategies for efficient load balancing on problems of increasing granularity are introduced and discussed. A four-level parallelization is developed based on a multi-level hierarchical grouping, and a high parallel efficiency is achieved on the Theta supercomputer using 131 072 OpenMP threads.

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Fedorov, Dmitri G., Pham, Buu Q.. 2023-04-26. Multi-level parallelization of quantum-chemical calculations. https://doi.org/10.1063/5.0144917

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