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arXiv · 2212.12559

Optimizing Staggered Multigrid for Exascale performance

Venkitesh Ayyar·Richard Brower·M. A. Clark·Mathias Wagner·Evan Weinberg
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Abstract

Adaptive multi-grid methods have proven very successful in dealing with critical slow down for the Wilson-Dirac solver in lattice gauge theory. Multi-grid algorithms developed for Staggered fermions using the K\"ahler-Dirac preconditioning~\cite{Brower:2018ymy} have shown remarkable success. In this work, we discuss the performance of this staggered multi-grid algorithm in four dimensions. We also demonstrate that offloading some components of a multi-shift solve to a multi-grid solver leads to a significant performance improvement in an existing MILC spectrum workflow on the Summit and Selene supercomputers.

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Venkitesh Ayyar, Richard Brower, M. A. Clark, Mathias Wagner, Evan Weinberg. 2022-12-23. Optimizing Staggered Multigrid for Exascale performance. https://doi.org/10.22323/1.430.0335

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