Mark, I have runs of GAMG on one and two ranks with -pc_gamg_symmetrize_graph because the matrix is far from symmetric and some of GAMG is taking a huge amount more time with 2 ranks than one. (While other stuff like VecNorm shows improvement with two ranks). I've attached the two files
Have you seen this before, is there anything that can be done about? If going to two ranks causes almost a doubling in GAMG setup time that makes using parallelism not useful, Barry
outMPI1
Description: Binary data
outMPI2
Description: Binary data