Thanks, Patrick. I will try your suggestion Richardson/SOR. Xiaodong Liu, PhD X: Computational Physics Division Los Alamos National Laboratory P.O. Box 1663, Los Alamos, NM 87544 505-709-0534
On Wed, Mar 18, 2020 at 10:34 AM Patrick Sanan <[email protected]> wrote: > I may not be interpreting the question correctly, but you can use SOR as > the only preconditioner, e.g. > > -ksp_type gmres -pc_type sor > > or you can use Richardson/SOR as your multigrid smoother, which might be > what you're asking for > > -ksp_type gmres -pc_type mg -pc_mg_levels 3 > -mg_levels_ksp_type richardson -mg_levels_pc_type SOR > > > > Am Mi., 18. März 2020 um 18:19 Uhr schrieb Xiaodong Liu <[email protected]>: > >> Hi, Petsc team, >> >> I am doing something using multigrid as a preconditioner for GMRES. From >> the official case, >> >> most use KSP (Chebyshev) and PC (SOR) for solving the preconditioning >> system for every level of multigrid except the coarse one. >> >> -ksp_type gmres -pc_type mg -pc_mg_levels 3 >> -mg_levels_ksp_type Chebyshev -mg_levels_pc_type SOR >> >> I would like to use SOR for solving the preconditioning system >> directly. I can not find that Petsc supports non-KSP iterative solver for a >> linear system, right? >> >> If I am wrong, please let me know. >> >> Xiaodong Liu, PhD >> X: Computational Physics Division >> Los Alamos National Laboratory >> P.O. Box 1663, >> Los Alamos, NM 87544 >> 505-709-0534 >> >
