ShyLU swMATH ID: 18568 Software Authors: Rajamanickam S., Boman E.G., Heroux M.A. Description: ShyLU: A Hybrid-Hybrid Solver for Multicore Platforms. With the ubiquity of multicore processors, it is crucial that solvers adapt to the hierarchical structure of modern architectures. We present ShyLU, a “hybrid-hybrid” solver for general sparse linear systems that is hybrid in two ways: First, it combines direct and iterative methods. The iterative part is based on approximate Schur complements where we compute the approximate Schur complement using a value-based dropping strategy or structure-based probing strategy. Second, the solver uses two levels of parallelism via hybrid programming (MPI+threads). ShyLU is useful both in shared-memory environments and on large parallel computers with distributed memory. In the latter case, it should be used as a subdomain solver. We argue that with the increasing complexity of compute nodes, it is important to exploit multiple levels of parallelism even within a single compute node. We show the robustness of ShyLU against other algebraic preconditioners. ShyLU scales well up to 384 cores for a given problem size. We also study the MPI-only performance of ShyLU against a hybrid implementation and conclude that on present multicore nodes MPI-only implementation is better. However, for future multicore machines (96 or more cores) hybrid/ hierarchical algorithms and implementations are important for sustained performance. Homepage: http://ieeexplore.ieee.org/document/6267865/ Related Software: Trilinos; FROSch; Amesos2; IFPACK; lobpcg.m Cited in: 3 Documents all top 5 Cited by 9 Authors 2 Heinlein, Alexander 2 Klawonn, Axel 2 Rheinbach, Oliver 1 Knepper, Jascha 1 Kopysov, Sergeĭ Petrovich 1 Kuz’min, Igor’ Mikhaĭlovich 1 Nedozhogin, Nikita Sergeevich 1 Novikov, Aleksandr Konstantinovich 1 Rajamanickam, Sivasankaran Cited in 2 Serials 1 SIAM Journal on Scientific Computing 1 Uchenye Zapiski Kazanskogo Universiteta. Seriya Fiziko-Matematicheskie Nauki Cited in 2 Fields 3 Numerical analysis (65-XX) 1 Linear and multilinear algebra; matrix theory (15-XX) Citations by Year