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arXiv · 2506.05793

ShyLU node: On-node Scalable Solvers and Preconditioners Recent Progresses and Current Performance

Ichitaro Yamazaki·Nathan Ellingwood·Sivasankaran Rajamanickam
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Abstract

ShyLU-node is an open-source software package that implements linear solvers and preconditioners on shared-memory multicore CPUs or on a GPU. It is part of the Trilinos software framework and designed to provide a robust and efficient solution of large-scale linear systems from real-world applications on the current and emerging computers. In this paper, we discuss two sparse direct solvers, Basker and Tacho, and an algebraic preconditioner, FastILU, in ShyLU-node package. These ShyLU solvers and preconditioner can be used as a stand-alone global problem solver, as a local subdomain solver for domain decomposition (DD) preconditioner, or as the coarse-problem solver in algebraic multi-grid preconditioner. We present performance results with the sparse direct solvers for real application problems, namely, Basker for Xyce Circuit Simulations and Tacho for Albany Land-Ice Simulation of Antarctica. FastILU has been also used in real-world applications, but in this paper, we illustrate its performance using 3D model problems.

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Ichitaro Yamazaki, Nathan Ellingwood, Sivasankaran Rajamanickam. 2025-06-06. ShyLU node: On-node Scalable Solvers and Preconditioners Recent Progresses and Current Performance. https://arxiv.org/abs/2506.05793

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