> On May 4, 2017, at 12:52 PM, Hom Nath Gharti <[email protected]> wrote: > > Thanks, Barry. Is there a way to take advantage of the fact that the > matrix remains same during time steps?
Yes since you are not changing the matrix it will construct the preconditioner once and just use it forever. > > On Thu, May 4, 2017 at 1:47 PM, Barry Smith <[email protected]> wrote: >> >>> On May 4, 2017, at 12:10 PM, Hom Nath Gharti <[email protected]> wrote: >>> >>> Dear all, >>> >>> I am trying to solve a Poisson's equation on the Earth models with the >>> following information >>> >>> - Degrees of freedom ~300,000,000 >>> - I use MPIAIJ matrix >>> - Coefficient matrix is symmetric and doesn't change with time steps >>> - Need to compute for a large number of time steps >>> >>> Which solver/preconditioner is the most efficient for this problem? I >>> would be grateful for your suggestion. >> >> Geometric multigrid is always best if you can use it. If not I would use >> hypre BoomerAMG, it should have very good convergence. >> >> >>> >>> Thanks, >>> Hom Nath >>
