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arXiv · 1709.01828

Optimization of the Brillouin operator on the KNL architecture

Stephan Durr
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Abstract

Experiences with optimizing the matrix-times-vector application of the Brillouin operator on the Intel KNL processor are reported. Without adjustments to the memory layout, performance figures of 360 Gflop/s in single and 270 Gflop/s in double precision are observed. This is with N_c=3 colors, N_v=12 right-hand-sides, N_{thr}=256 threads, on lattices of size 32^3*64, using exclusively OMP pragmas. Interestingly, the same routine performs quite well on Intel Core i7 architectures, too. Some observations on the much harder Wilson fermion matrix-times-vector optimization problem are added.

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Stephan Durr. 2017-09-06. Optimization of the Brillouin operator on the KNL architecture. https://doi.org/10.1051/epjconf/201817502001

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