[petsc-users] subdomain solver options

[Matthew Knepley]

See you next week!

   Matt

On Wed, Aug 27, 2025 at 3:39 AM Anton Popov <popov at uni-mainz.de> wrote:

> Thanks Matt, it works!
>
> Anton
> On 26.08.25 22:34, Matthew Knepley wrote:
>
> On Tue, Aug 26, 2025 at 12:45 PM Anton Popov <popov at uni-mainz.de> wrote:
>
>> There is an important addition, I use asm and bjacobi as smoothers on
>> multigrid levels.
>>
>> So I probably need to set the options with -mg_levels_sub_, or
>> -mg_levels_3_sub_(if they are different on different levels), instead of
>> just -sub_.
>>
>> Correct?
>>
>
> Yes, and as Mark says, you can see the prefix if you View the solver.
>
>   Thanks,
>
>      Matt
>
>
>> Anton
>>
>>
>>
>> On 26.08.25 18:20, Anton Popov wrote:
>> > Hi all,
>> >
>> > I have a strange behavior setting the solver options for asm and
>> > bjacobi blocks.
>> >
>> > Irrespective of what I set with -sub_ksp_ -sub_pc_ it just selects the
>> > default preonly and ilu options.
>> >
>> > This behavior does not change no matter how many local blocks per cpu
>> > I try to use, for example with the default one block/cpu it does not
>> > work as well.
>> >
>> > Is there anything wrong?
>> >
>> > Best,
>> >
>> > Anton
>> >
>>
>
>
> --
> What most experimenters take for granted before they begin their
> experiments is infinitely more interesting than any results to which their
> experiments lead.
> -- Norbert Wiener
>
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>

-- 
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which their
experiments lead.
-- Norbert Wiener

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