[petsc-users] testing scalability for ksp/ex22.c

Jed Brown jedbrown at mcs.anl.gov
Thu Feb 23 20:24:17 CST 2012


On Thu, Feb 23, 2012 at 18:58, Francis Poulin <fpoulin at uwaterloo.ca> wrote:

> I can do it for each of them if that helps but I suspect the method is the
> same so I'm sending the information for the first 3, n = 2, 4, 8.  In the
> mean  time I will figure out how to change the number of levels..
>

There are only three levels. The coarsest level has 32k degrees of freedom,
which is very expensive to solve (redundantly) with a direct solver.

Run this, it's higher resolution and will be much faster than what you had.

mpiexec -n 2 ./ex22 -da_grid_x 5 -da_grid_y 5 -da_grid_z 5 -dmmg_nlevels 6
-ksp_monitor -mg_levels_ksp_type richardson -mg_levels_pc_type sor
-log_summary


Also, please switch to a more recent release of PETSc as soon as possible
and do not develop new code using DMMG since that component has been
removed (and its functionality incorporated into SNES and KSP).
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120223/e3786d3d/attachment.htm>


More information about the petsc-users mailing list