On Nov 30, 2012, at 11:30 AM, Matthew Knepley <knepley at gmail.com> wrote:
>
> On Nov 30, 2012 11:17 AM, "Barry Smith" <bsmith at mcs.anl.gov> wrote:
> >
> >
> > I would like to add to the _p_DM struct
> >
> > PetscObject dmksp, dmsnes, dmts.
> >
> > The current model that uses PetscObjectCompose() is a mis-use of
> > PetscObjectCompose(), why?
> >
> > The PetscObjectQuery() is always used for every function evaluation in
> > every time step, every Newton step, ?
> >
> > 1) this is a performance problem with small size ODEs for example
> >
> > 2) PetscObjectQuery is suppose to be for exceptional things that occur
> > seldomly, not ones that occur inside the main computational routes.
> >
> >
> >
> > Please send any technical (not philosophical) reasons why making this
> > change is a bad idea and will haunt us later.
>
> There is an extensibility problem that Jed has already noted.
That is only a philosophical objection :-) If one wishes to add a
DMGetDMTAOSomething() they can implement it with the PetscObjectCompose() model
so things are still extensible.
Barry
>
> Matt
>
> > Barry
> >
> >
> >
> >
>
