[Nek5000-users] Problem size requires AMG solver

[nek5000-users at lists.mcs.anl.gov]

What's the reason not use the AMG solver?

-----Original message-----
> From:nek5000-users at lists.mcs.anl.gov <nek5000-users at lists.mcs.anl.gov>
> Sent: Thursday 7th June 2018 13:59
> To: nek5000-users at lists.mcs.anl.gov
> Subject: [Nek5000-users] Problem size requires AMG solver
> 
> Hi everyone,
> I need to run a case in Nek with a large number of elements (~ 1 million).
> The same problem with a small number of elements works fine, but on the larger grid
> the solver exits with the following error: 
>     EXIT: Problem size requires AMG solver          1
> Going through the code
> # if (imode.eq.0 .and. nelgt.gt.350000) call exitti(
> #   $ 'Problem size requires AMG solver$',1)
> It seems that over 350000 elements, you need to use the AMG solver.
> Is that correct? Or is there any workaround to not use the AMG.
> Kind regards,
> Dante De Santis
> Research Consultant Computational Physics 4 Solutions
> [NRG - Research and Innovation Unit]
> Westerduinweg 3, 1755 LE  PETTEN
> 
> P.O. Box 25, 1755 ZG  PETTEN 
> THE NETHERLANDS
> phone: 31(0) 224 56 4656
> e-mail: desantis at nrg.eu <mailto:desantis at nrg.eu>
> Visit NRG at
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