On Jun 22, 2016, at 10:20 PM, Mark Adams <[email protected]> wrote:

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No joke, Amneet found that PCASM with lots of small subdomains was spending a ton of time in view calls.

(And, of course, Barry fixed it by adding this configure flag --- thanks Barry!)

Note that it does not matter whether you use view or not.

Oh wow. So no view with ASM,

Garth, you will need to configure with '--with-viewfromoptions=0'

Not really, first we make sure it runs correctly and only then do we optimize. Please send me the arguments for the crash case with gasm so I can debug it. Thanks Barry

-- Boyce

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-- Boyce

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I guess we should have a flag or not iterate over the blocks in ASMView ...

-- Boyce

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Barry

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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