> On 6 Nov 2015, at 17:39, Barry Smith <[email protected]> wrote: > > > If it is a true mass matrix in the finite element sense of the word then it > should be very well conditioned and one definitely would not use something > like GAMG on. Jacobi + CG or maybe SSOR + CG should converge rapidly
That I understand and absolutely agree. It just does not explain why GAMG would fail, especially on 4 cores and not on 8. Regards, Denis.
