Hi Knut, I'm currently using boomeramg to solve my poisson eqn too. I'm using it on my structured C-grid. I found it to be faster than LU, especially as the grid size increases. However I use it as a preconditioner with GMRES as the solver. Have you tried this option? Although it's faster, the speed increase is usually less than double. It seems to be worse if there is a lot of stretching in the grid.
Btw, your mention using the DMMG framework and it takes less than a sec. What solver or preconditioner did you use? It's 4 times faster than GMRES... thanks! knutert at stud.ntnu.no wrote: > Hello, > > I am trying to use the hypre multigrid solver to solve a Poisson > equation. > However, on a test case with grid size 257x257 it takes 40 seconds to > converge > on one processor when I run with > ./run -ksp_type richardson -pc_type hypre -pc_type_hypre boomeramg > > Using the DMMG framework, the same problem takes less than a second, > and the default gmres solver uses only four seconds. > > Am I somehow using the solver the wrong way, or is this performance > expected? > > Regards > Knut Erik Teigen > >
