On Tue, Dec 7, 2010 at 22:37, Dmitry Karpeev <karpeev at mcs.anl.gov> wrote:
> I may be out on a limb here, but the column DM could also encapsulate the > scatter > that currently sits in the Mat object. By default the row DM could have an > identity (noop) scatter. > > Note that this is very natural from the DD standpoint: ASM/GASM/FieldSplit > already define scatters that > scatter to a "subdomain" on which a matrix/pc operate. Currently, the > VecScatter inside the subdomain Mat > will further scatter the Vec to the "local" part, on which the matrix then > operates locally. If the scatter is moved > out of Mat and into its column DM, than this double scatter can be avoided. > Hmm, now the DM is starting to know a lot. There are times where I think fusing scatters is good, but this one sounds tricky. How would you implement this? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20101207/cef04e2d/attachment.html>