On Fri, Oct 5, 2018 at 9:16 PM Mike Wick <[email protected]> wrote:
> Hi Hong: > > There is no explicit error message actually. The solver converge in 0 > iteration and returns an nan number. Looks like a zero pivoting problem. > > Mike > I use MatMumpsGetInfo <https://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatMumpsGetInfo.html> to get error info returned by MUMPS, e.g. PetscInt info_1; MatMumpsGetInfo(pc_mat, 1, &info_1); Then you can check the value of info_1 to get error diagnostics. One error that I run into sometimes is when info_1 is -9, in which case I increase icntl_14 and try again. Best, David > > On Fri, Oct 5, 2018 at 6:12 PM Zhang, Hong <[email protected]> wrote: > >> Mike: >> >>> Hello PETSc team: >>> >>> I am trying to solve a PDE problem with high-order finite elements. The >>> matrix is getting denser and my experience is that MUMPS just outperforms >>> iterative solvers. >>> >>> For certain problems, MUMPS just fail in the middle for no clear reason. >>> I just wander if there is any suggestion to improve the robustness of >>> MUMPS? Or in general, any suggestion for interative solver with very >>> high-order finite elements? >>> >> >> What error message do you get when MUMPS fails? Out of memory, zero >> pivoting, or something? >> Hong >> >
