On Wed, Jun 22, 2016 at 8:14 PM, Boyce Griffith <[email protected]> wrote:
> > On Jun 22, 2016, at 2:06 PM, Barry Smith <[email protected]> wrote: > > > I suggest focusing on asm. Having blocks that span multiple processes > seems like over kill for a smoother ? (Major league overkill) in fact > doesn't one want multiple blocks per process, ie. pretty small blocks. > > > And with lots of small blocks, remember to configure > with --with-viewfromoptions=0. :-) > Yikes. That is overkill right, unless you are worried about (users) accidentally using view and crashing the run with output. I guess we should have a flag or not iterate over the blocks in ASMView ... > > -- Boyce > > > Barry > > On Jun 22, 2016, at 7:51 AM, Mark Adams <[email protected]> wrote: > > I'm trying to get block smoothers to work for gamg. We (Garth) tried this > and got this error: > > > - Another option is use '-pc_gamg_use_agg_gasm true' and use > '-mg_levels_pc_type gasm'. > > > Running in parallel, I get > > ** Max-trans not allowed because matrix is distributed > ---- > > First, what is the difference between asm and gasm? > > Second, I need to fix this to get block smoothers. This used to work. Did > we lose the capability to have blocks that span processor subdomains? > > gamg only aggregates across processor subdomains within one layer, so > maybe I could use one layer of overlap in some way? > > Thanks, > Mark > > >
