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arXiv · 2001.04886

s-Step Orthomin and GMRES implemented on parallel computers

A. T. Chronopoulos·S. K. Kim
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Abstract

The Orthomin ( Omin ) and the Generalized Minimal Residual method ( GMRES ) are commonly used iterative methods for approximating the solution of non-symmetric linear systems. The s-step generalizations of these methods enhance their data locality parallel and properties by forming s simultaneous search direction vectors. Good data locality is the key in achieving near peak rates on memory hierarchical supercomputers. The theoretical derivation of the s-step Arnoldi and Omin has been published in the past. Here we derive the s-step GMRES method. We then implement s-step Omin and GMRES on a Cray-2 hierarchical memory supercomputer.

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A. T. Chronopoulos, S. K. Kim. 2020-01-14. s-Step Orthomin and GMRES implemented on parallel computers. https://arxiv.org/abs/2001.04886

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