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arXiv · 2312.15747

A Comparison of Image and Scalar-Based Approaches in Preconditioner Selection

Michael Souza·Luiz M. Carvalho·Douglas Augusto·Jairo Panetta·Paulo Goldfeld·José R. P. Rodrigues
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Abstract

Within high-performance computing (HPC), solving large sparse linear systems efficiently remains paramount, with iterative methods being the predominant choice. However, the performance of these methods is tightly coupled to the aptness of the chosen preconditioner. The multifaceted nature of sparse matrices makes the universal prescription of preconditioners elusive. Notably, the key attribute of sparsity is not precisely captured by scalar metrics such as bandwidth or matrix dimensions. Advancing prior methodologies, this research introduces matrix sparsity depiction via RGB images. Utilizing a convolutional neural network (CNN), the task of preconditioner selection turns into a multi-class classification problem. Extensive tests on 126 SuiteSparse matrices emphasize the enhanced prowess of the CNN model, noting a 32% boost in accuracy and a 25% reduction in computational slowdown.

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Michael Souza, Luiz M. Carvalho, Douglas Augusto, Jairo Panetta, Paulo Goldfeld, José R. P. Rodrigues. 2023-12-25. A Comparison of Image and Scalar-Based Approaches in Preconditioner Selection. https://arxiv.org/abs/2312.15747

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