[petsc-users] odd SNES behavior

[Mark F. Adams]

I have a SNES solve if I switch the pc_type between gamg and hypre I get some odd results:

1) The gamg solve takes two more Newton iterations and converges for a different reason.  This could be OK, but it seems odd.

2) The more mystifying issue is that the gamg solve seems to take just a few more total linear solve iterations but does about 5x as many function evaluations.

I've attached two log files.  Any ideas what is going on here?  It seems like it should be impossible for the choice of PC to effect the nonlinear solve like this.

Mark
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