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arXiv · 1708.00033

An efficient MPI/OpenMP parallelization of the Hartree-Fock method for the second generation of Intel Xeon Phi processor

Vladimir Mironov·Yuri Alexeev·Kristopher Keipert·Michael D'mello·Alexander Moskovsky·Mark S. Gordon
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Abstract

Modern OpenMP threading techniques are used to convert the MPI-only Hartree-Fock code in the GAMESS program to a hybrid MPI/OpenMP algorithm. Two separate implementations that differ by the sharing or replication of key data structures among threads are considered, density and Fock matrices. All implementations are benchmarked on a super-computer of 3,000 Intel Xeon Phi processors. With 64 cores per processor, scaling numbers are reported on up to 192,000 cores. The hybrid MPI/OpenMP implementation reduces the memory footprint by approximately 200 times compared to the legacy code. The MPI/OpenMP code was shown to run up to six times faster than the original for a range of molecular system sizes.

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Vladimir Mironov, Yuri Alexeev, Kristopher Keipert, Michael D'mello, Alexander Moskovsky, Mark S. Gordon. 2017-07-31. An efficient MPI/OpenMP parallelization of the Hartree-Fock method for the second generation of Intel Xeon Phi processor. https://doi.org/10.1145/3126908.3126956

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