Parallel Multigrid Methods

10:00 AM-12:30 PM

*Room: Ballroom A*

Modern simulation codes must solve extremely large systems of equations- tens, even hundreds of millions of equations. Hence, there is an acute need for scalable parallel linear solvers, i.e., algorithms for which the time to solution (or number of iterations) remains constant as both problem size and number of processors increase. Multigrid, known to be an optimal serial algorithm, is often scalable when implemented on a parallel computer. The speakers in this minisymposium will discuss parallelizing multigrid solvers for various problems and architectures. The machines range from the high-end ASCI machines, with thousands of processors, to low-cost clusters of workstations.

**Organizer: Van Emden Henson**

*Lawrence Livermore National Laboratory*

**10:00-10:20 Parallel Semicoarsening Multigrid***Jim E. Jones*and Robert D. Falgout, Lawrence Livermore National Laboratory**10:25-10:45 Transpose-Free Parallel ADI Methods in Multigrid**

*Craig C. Douglas*, University of Kentucky; Sachit Malhotra, Morgan Stanley Dean Witter; and Martin H. Schultz, Yale University

**10:50-11:10 Approaches to Parallel Multigrid with the Full Domain Partition**

- William F. Mitchell, National Institute of Standards and
Technology, Gaithersburg

**11:15-11:35 Parallel Multigrid Solver of Unstructured Finite Element Problems in Non-Linear Solid Mechanics**

*Mark Adams*, University of California, Berkeley

**11:40-12:00 Design of a Multilevel Module for Parallel Unstructured Grid Computations**

- Karen Devine, John Shadid, Charles Tong and
*Ray Tuminaro*, Sandia National Laboratories, Livermore

**12:05-12:25 A Parallel Implementation of Algebraic Multigrid**

*Van Emden Henson*, Organizer; Robert D. Falgout, Jim E. Jones and Ulrike Meier Yang, Lawrence Livermore National Laboratory

*LMH, 10/28/98, MMD, 11/16/98*