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arXiv · 1703.01325

Decoupled Block-Wise ILU(k) Preconditioner on GPU

Bo Yang·Hui Liu·He Zhong·Zhangxin Chen
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Abstract

This research investigates the implementation mechanism of block-wise ILU(k) preconditioner on GPU. The block-wise ILU(k) algorithm requires both the level k and the block size to be designed as variables. A decoupled ILU(k) algorithm consists of a symbolic phase and a factorization phase. In the symbolic phase, a ILU(k) nonzero pattern is established from the point-wise structure extracted from a block-wise matrix. In the factorization phase, the block-wise matrix with a variable block size is factorized into a block lower triangular matrix and a block upper triangular matrix. And a further diagonal factorization is required to perform on the block upper triangular matrix for adapting a parallel triangular solver on GPU.We also present the numerical experiments to study the preconditioner actions on different k levels and block sizes.

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Bo Yang, Hui Liu, He Zhong, Zhangxin Chen. 2017-03-03. Decoupled Block-Wise ILU(k) Preconditioner on GPU. https://arxiv.org/abs/1703.01325

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