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Iterative Sparse Triangular Solves for Preconditioning

  • Hartwig AnztEmail author
  • Edmond Chow
  • Jack Dongarra
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9233)

Abstract

Sparse triangular solvers are typically parallelized using level-scheduling techniques, but parallel efficiency 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.

Notes

Acknowledgments

This material is based upon work supported by the U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing Research, Applied Mathematics program under Award Numbers DE-SC-0012538 and DE-SC-0010042. Support from NVIDIA is also gratefully acknowledged.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.University of TennesseeKnoxvilleUSA
  2. 2.Georgia Institute of TechnologyAtlantaUSA

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