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.
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 >
