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arXiv · 2312.14715

Resilient asynchronous primal Schur method

Guillaume Gbikpi-Benissan·Frédéric Magoulès
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Abstract

This paper introduces the application of the asynchronous iterations theory within the framework of the primal Schur domain decomposition method. A suitable relaxation scheme is designed, which asynchronous convergence is established under classical spectral radius conditions. For the usual case where the local Schur complement matrices are not constructed, suitable splittings only based on explicitly generated matrices are provided. Numerical experiments are conducted on a supercomputer for both Poisson's and linear elasticity problems. The asynchronous Schur solver outperformed the classical conjugate-gradient-based one in case of compute node failures.

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Guillaume Gbikpi-Benissan, Frédéric Magoulès. 2023-12-22. Resilient asynchronous primal Schur method. https://doi.org/10.21136/am.2022.0146-21

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