[petsc-dev] DMMG without libpetscsnes?

[Barry Smith]

    You misunderstood my comment. I was not not trying to state that  
linear problems are silly, not at all. Only that I'm not interesting  
in adaptive mesh refinement on a purely linear problem.

    Barry

On Jan 7, 2010, at 3:06 PM, Jed Brown wrote:

> On Thu, 7 Jan 2010 14:52:41 -0600, Barry Smith <bsmith at mcs.anl.gov>  
> wrote:
>
>>    There would be no SNES in this context!  One would be able to
>> cleanly and simply (more so then today) put geometric multigrid  
>> inside
>> a Schure fieldsplit preconditioner. If one can't then we screwed up
>> our new design.
>
> I think we're agreeing.  My comment was just a retort to the claim  
> that
> linear problems are silly.  They are silly if that's your end goal,  
> and
> I believe they are still silly when using a scheme where the quality  
> of
> your solution depends on the quality of the linear solve (as in a
> semi-implicit scheme), but having a nice interface for linear MG is
> important when it goes inside a preconditioner.  In contrast, I think
> that all special treatment of linear problems could be stripped out of
> TS with no ill consequences.
>
> Jed