[petsc-users] Automatic partition of Cartesian grids

[Matthew Knepley]

On Fri, Nov 11, 2011 at 2:26 PM, TAY wee-beng <zonexo at gmail.com> wrote:

> Hi,
>
> I am currently using PETSc for my Fortran CFD code and I am manually
> partitioning my Cartesian grids. So in 2D, it will be something like
> u(1:size_x,jstart:jend), where the y component is partitioned into 2,4,8
> etc parts depending on the no. of processors.
>
> However, it seems that there are better ways to do it to get a more
> balanced load. Do I use DMDA in PETSc to do it? I'm now using staggered
> Cartesian grids for my u,v,p. Is there an example to construct a
> Laplace/Poisson equation using DMDA?
>

Yes use DMDA. Look at SNES ex5 and ex50.


> It is mentioned in the manual that DMMG infrastructure will be replaced in
> the next release and we should not use it. Is this related to DMDA?
>

Only if you use multigrid.

   Matt


> Yours sincerely,
>
> TAY wee-beng
>
>
>


-- 
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
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20111111/20c6e0a6/attachment.htm>