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arXiv · 1307.6101

An adaptive aggregation based domain decomposition multilevel method for the lattice wilson dirac operator: multilevel results

A. Frommer·K. Kahl·S. Krieg·B. Leder·M. Rottmann
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Abstract

In lattice QCD computations a substantial amount of work is spent in solving linear systems arising in Wilson's discretization of the Dirac equations. We show first numerical results of the extension of the two-level DD-αAMG method to a true multilevel method based on our parallel MPI-C implementation. Using additional levels pays off, allowing to cut down the core minutes spent on one system solve by a factor of approximately 700 compared to standard Krylov subspace methods and yielding another speed-up of a factor of 1.7 over the two-level approach.

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A. Frommer, K. Kahl, S. Krieg, B. Leder, M. Rottmann. 2013-07-23. An adaptive aggregation based domain decomposition multilevel method for the lattice wilson dirac operator: multilevel results. https://arxiv.org/abs/1307.6101

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