KSP/PC choice

[Tim Kröger]

Dear gaatenek

On Mon, 23 Jul 2007, gaatenek at irisa.fr wrote:

> Do you monitoring the convergence? Try it a see if you have stagnation in
> your convergence.

Yes, I monitor it, but that doesn't seem to give me any helpful 
information -- except that it stagnates of course.

> However you can  try this setting,
> -ksp_type gmres
> -ksp_gmres_restart 30
> -pc_type asm
> -pc_asm_overlap 2
> -sub_pc_type ilu
> -sub_pc_factor_zeropivot 0
> -sub_pc_ilu_levels 3

Thank you, I tried it, and it worked well for a test case.  However, 
for the real application, the PC eats up all my memory (even in cases 
where my former setting did work).

Any hints (except buying a larger computer)?

Might some sub_ksp method help?

Best Regards,

Tim

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