dolfin team mailing list archive

[Niclas Jansson <njansson@xxxxxx>]

On Mon, 18 Feb 2008 18:31:54 +0100
Anders Logg <logg@xxxxxxxxx> wrote:


> > We (Nicklas) have now a preliminary distributed parallel
> > implementation running for Poisson and a Unicorn flow solver. The
> > structure is still quite messy and the partitioning is based on
> > Metis, but we expect it to be integrated with DOLFIN in the coming
> > months, hopefully before the summer.
> 
> Could this be done in small pieces? I'm a little worried about seeing
> big changesets that add things to the mesh classes.
> 
> > When the structure is more clear we can discuss on the mailing list
> > how to best incorporate this into DOLFIN. Apart from the structure
> > of the implementation we are also focusing on distributed local mesh
> > refinement.
> 
> Great.
> 
> What is the difference from what we have now? Is it the same but with
> a distributed mesh (so each processor just sees the local part, not
> the whole mesh)? Or is it something different?
> 

Yes, each processor only sees the local part. The entire problem is
never represented on one processor. Preprocessing, assembly, solution
and postprocessing are all done without gathering/scattering data
to/from one processor.

The only modification to the mesh classes is a new class storing
information about ghost points and vertex local to global mapping.

Most of the messy parts are inside the function classes.


Niclas