English

A Direct Elliptic Solver Based on Hierarchically Low-rank Schur Complements

Numerical Analysis 2017-12-27 v1

Abstract

A parallel fast direct solver for rank-compressible block tridiagonal linear systems is presented. Algorithmic synergies between Cyclic Reduction and Hierarchical matrix arithmetic operations result in a solver with O(Nlog2N)O(N \log^2 N) arithmetic complexity and O(NlogN)O(N \log N) memory footprint. We provide a baseline for performance and applicability by comparing with well known implementations of the H\mathcal{H}-LU factorization and algebraic multigrid with a parallel implementation that leverages the concurrency features of the method. Numerical experiments reveal that this method is comparable with other fast direct solvers based on Hierarchical Matrices such as H\mathcal{H}-LU and that it can tackle problems where algebraic multigrid fails to converge.

Keywords

Cite

@article{arxiv.1604.00617,
  title  = {A Direct Elliptic Solver Based on Hierarchically Low-rank Schur Complements},
  author = {Gustavo Chávez and George Turkiyyah and David Keyes},
  journal= {arXiv preprint arXiv:1604.00617},
  year   = {2017}
}
R2 v1 2026-06-22T13:24:04.811Z