[petsc-dev] ASM request

[Matthew Knepley]

On Tue, Mar 16, 2010 at 2:35 PM, Jed Brown <jed at 59a2.org> wrote:

> On Tue, 16 Mar 2010 14:12:03 -0400, Matthew Knepley <knepley at gmail.com>
> wrote:
> >    You have a preconditioner which is ASM, but with a LOT of small
> > blocks.  You do not save very much by discarding one big block, but if
> > you only ever form each small block, you get a lot of savings.
>
> Unless I misunderstand you, this means that you'll be refactoring each
> block on every Krylov iteration.  I realize it's a bit less memory, but
> that's going to be pretty painful.


If the number one thing is how big a problem can be run, they will tolerate
ait.

  Matt


>
> Jed

-- 
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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