Iterative Sparse Triangular Solves for Preconditioning

TitleIterative Sparse Triangular Solves for Preconditioning
Publication TypeConference Paper
Year of Publication2015
AuthorsAnzt, H., E. Chow, and J. Dongarra
Conference NameEuroPar 2015
Date Published08-2015
PublisherSpringer Berlin
Conference LocationVienna, Austria

Sparse triangular solvers are typically parallelized using level scheduling techniques, but parallel eciency is poor on high-throughput architectures like GPUs. We propose using an iterative approach for solving sparse triangular systems when an approximation is suitable. This approach will not work for all problems, but can be successful for sparse triangular matrices arising from incomplete factorizations, where an approximate solution is acceptable. We demonstrate the performance gains that this approach can have on GPUs in the context of solving sparse linear systems with a preconditioned Krylov subspace method. We also illustrate the effect of using asynchronous iterations.