[petsc-users] Database key for KSP_Solve

[Xuefeng Li]

On Fri, 15 Jun 2012, Matthew Knepley wrote:

> On Fri, Jun 15, 2012 at 3:08 AM, Xuefeng Li <li at loyno.edu> wrote:
>
>> Are there any database keys to control the number of
>> times KSP_Solve() is called? Where is the loop that
>> calls KSP_Solve?  The key -ksp_max_it does not seem
>> to affect it.
>>
>
> Then this option did not reach the solver. You may have set a prefix.
>
> Run with -snes_max_it 1 -ksp_max_it 1 -snes_view to see what you are
> actually doing.
>
The key -ksp_max_it affects the iteration number
for the (main) ksp object for SNES, but not the ksp
object for PC.

I observed yet another (related) problem. Even though
I set KSP type to be GMRES, the type is GMRES only on
the coarse level of the DMMG; the type changes to MG
on all finer levels. How do I control KSP and PC on
finer levels of DMMG?

Regards,

--Xuefeng Li, (504)865-3340(phone)
   Like floating clouds, the heart rests easy
   Like flowing water, the spirit stays free
        http://www.loyno.edu/~li/home
   New Orleans, Louisiana (504)865-2051(fax)