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arXiv · 1808.05506

Three Dirac operators on two architectures with one piece of code and no hassle

Stephan Durr
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Abstract

A simple minded approach to implement three discretizations of the Dirac operator (staggered, Wilson, Brillouin) on two architectures (KNL and core i7) is presented. The idea is to use a high-level compiler along with OpenMP parallelization and SIMD pragmas, but to stay away from cache-line optimization and/or assembly-tuning. The implementation is for N_v right-hand-sides, and this extra index is used to fill the SIMD pipeline. On one KNL node single precision performance figures for N_c=3, N_v=12 read 475 Gflop/s, 345 Gflop/s, and 790 Gflop/s for the three discretization schemes, respectively.

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Stephan Durr. 2018-08-16. Three Dirac operators on two architectures with one piece of code and no hassle. https://arxiv.org/abs/1808.05506

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