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<div class="moz-cite-prefix">Hi Barry,<br>
<br>
My command line is :<br>
<br>
mpiexec -np 46 ./a.out -options_left -poisson_ksp_view
-poisson_ksp_type gmres -poisson_pc_type hypre
-poisson_pc_type_hypre boomeramg > log<br>
<br>
My result is :<br>
<br>
<i><b>KSP Object:(poisson_) 46 MPI processes<br>
type: gmres<br>
GMRES: restart=30, using Classical (unmodified)
Gram-Schmidt Orthogonalization with no iterative refinement<br>
GMRES: happy breakdown tolerance 1e-30<br>
maximum iterations=10000, initial guess is zero<br>
tolerances: relative=1e-05, absolute=1e-50,
divergence=10000<br>
left preconditioning<br>
using PRECONDITIONED norm type for convergence test<br>
PC Object:(poisson_) 46 MPI processes<br>
type: hypre<br>
HYPRE BoomerAMG preconditioning<br>
HYPRE BoomerAMG: Cycle type V<br>
HYPRE BoomerAMG: Maximum number of levels 25<br>
HYPRE BoomerAMG: Maximum number of iterations PER hypre
call 1<br>
HYPRE BoomerAMG: Convergence tolerance PER hypre call 0<br>
HYPRE BoomerAMG: Threshold for strong coupling 0.25<br>
HYPRE BoomerAMG: Interpolation truncation factor 0<br>
HYPRE BoomerAMG: Interpolation: max elements per row 0<br>
HYPRE BoomerAMG: Number of levels of aggressive coarsening
0<br>
HYPRE BoomerAMG: Number of paths for aggressive coarsening
1<br>
HYPRE BoomerAMG: Maximum row sums 0.9<br>
HYPRE BoomerAMG: Sweeps down 1<br>
HYPRE BoomerAMG: Sweeps up 1<br>
HYPRE BoomerAMG: Sweeps on coarse 1<br>
HYPRE BoomerAMG: Relax down symmetric-SOR/Jacobi<br>
HYPRE BoomerAMG: Relax up symmetric-SOR/Jacobi<br>
HYPRE BoomerAMG: Relax on coarse Gaussian-elimination<br>
HYPRE BoomerAMG: Relax weight (all) 1<br>
HYPRE BoomerAMG: Outer relax weight (all) 1<br>
HYPRE BoomerAMG: Using CF-relaxation<br>
HYPRE BoomerAMG: Measure type local<br>
HYPRE BoomerAMG: Coarsen type Falgout<br>
HYPRE BoomerAMG: Interpolation type classical<br>
linear system matrix = precond matrix:<br>
Matrix Object: 46 MPI processes<br>
....<br>
<br>
...<br>
</b></i><i><b></b></i><i><b>#PETSc Option Table entries:<br>
-options_left<br>
-poisson_ksp_type gmres<br>
-poisson_pc_type hypre<br>
-poisson_pc_type_hypre boomeramg<br>
#End of PETSc Option Table entries<br>
There is one unused database option. It is:<br>
Option left: name:-poisson_pc_type_hypre value: boomeramg</b></i><br>
<br>
It seems that it is using boomeramg but why does it say "one
unused database option"?<br>
<br>
Did I do something wrong?<br>
<br>
Also if only my RHS of the Poisson eqn's changes, do I set the ksp
and pc once at the start? E.g. : <br>
<br>
call KSPSetType(ksp,ksptype,ierr)<br>
<br>
ksptype=KSPGMRES<br>
<br>
call PCSetType(pc,'hypre',ierr)<br>
<br>
call PCHYPREGetType(pc,'boomeramg',ierr)<br>
<br>
or do I have to do it at each time step?<br>
<pre class="moz-signature" cols="72">Thank you
Yours sincerely,
TAY wee-beng</pre>
On 18/3/2014 2:23 AM, Barry Smith wrote:<br>
</div>
<blockquote
cite="mid:BC951F9C-4EAA-44C6-8E32-4CD43B9EB645@mcs.anl.gov"
type="cite">
<pre wrap="">
Yes. You can run with -poisson_ksp_view and -options_left to make sure the options you provide are actually used.
Barry
On Mar 17, 2014, at 9:39 AM, TAY wee-beng <a class="moz-txt-link-rfc2396E" href="mailto:zonexo@gmail.com"><zonexo@gmail.com></a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Hi,
I use
call KSPSetOptionsPrefix(ksp_semi_xyz,"momentum_",ierr)
and
call KSPSetOptionsPrefix(ksp,"poisson_",ierr)
so that I can choose separate ksp/pc options for my momentum and poisson equations through command line e.g.
-poisson_ksp_type gmres -poisson_pc_type hypre -poisson_pc_type_hypre boomeramg
In general, I need to use boomeramg as the preconditioner and gmres as the solver for my poisson eqn, separate from my momentum eqn, which has its own default pc and ksp. Is the above the correct way?
Thanks!
--
Yours sincerely,
TAY wee-beng
</pre>
</blockquote>
<pre wrap="">
</pre>
</blockquote>
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