Singular matrix causes program to hang in MPI mode
In one porous flow simulation, I get this message:
Newton iteration 6 done, residual = 3.1654e+13
Solve: M deltax^k = rNewton: Caught exception: "FMatrixError [luDecomposition:/home/dpavlov/DUMUX/dune-common/dune/common/densematrix.hh:939]: matrix is singular"
... and it is fine. Matrix can be singular, no objection here. After this, the Newton solver reports that it did not converge and restarts with a smaller time step, and eventually it proceeds.
However, when I run the same simulation with MPI, I get this
Newton iteration 8 done, residual = 7.2437e+13
Solve: M deltax^k =
and the program hangs.