dolfin team mailing list archive

[Anders Logg <logg@xxxxxxxxx>]

On Sun, Dec 02, 2007 at 06:17:35PM +0100, Johan Hoffman wrote:
> >
> >
> > Johan Hoffman wrote:
> >>> Johan Hoffman wrote:
> >>>> Hi all,
> >>>>
> >>>> Connected to this discussion is also the msc thesis work on dolfin
> >>>> parallization of Nicklas Jansson at KTH. He has now started working on
> >>>> this based on the updated TODO list of dolfin. He has tried to send an
> >>>> email to this list (dolfin-dev@xxxxxxxxxx) but it appears that it is
> >>>> stuck
> >>>> in a filter awaiting moderator approval.
> >>> If he joins the list, he'll be able to make posts.
> >>
> >> Ok.
> >>
> >>> Maybe someone (a moderator) could
> >>>> help out so that we can get past this, to better coordinate
> >>>> parallelization efforts?
> >>>>
> >>> One point on the TODO list: we discussed some time ago the mesh
> >>> partitioning, and decided against ParMETIS or METIS because they do not
> >>> use a GPL (compatible) license. Magnus has implemented a nice
> >>> partitioning interface which uses SOCTCH which does have a GPL
> >>> compatible license.
> >>
> >> Ok. Does the switch to LGPL licence for dolfin make any difference? Or
> >> is
> >> it still a conflict?
> >>
> >
> > There is still a conflict. The METIS license basically says that it can
> > be used for non-profit purposes only, and permission is required to
> > re-distribute it.
> 
> Ok, then there is a problem.
> 
> >> About Scotch; the argument was that it lacked parallel partitioning, and
> >> a
> >> few other nice features of parMetis. But it seems that Scotch v5.0 is
> >> moving towards a parallel implementation as well?
> >>
> >
> > It does have it now. That said, I can't see us using or needing parallel
> > partitioning in the short- to medium-term future.
> 
> Ok. Maybe we'll manage with Scotch for now then.
> 
> As for parallel assembly, we will need this in the coming months, so we
> will push the fully parallel approach within Nicklas' msc project,
> including parallel redistribution for adaptively refined meshes (which
> parMetis seems to support nicely).
> 
> /Johan

Sounds very good, but if major changes to the Mesh classes are
necessary (which seems likely), I suspect I will be somewhat sensitive
to having all those changes pushed at once. So it would be good to
discuss plans for the design as early as possible so we can all feel
comfortable with the changes.

-- 
Anders