Mark: > >> > > [2998]PETSC ERROR: #2 PetscTableCreate() line 52 in >> > > /global/u2/m/madams/petsc_install/petsc/src/sys/utils/ctable.c >> > > [2998]PETSC ERROR: #3 MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ() >> line 1691 >> > MatTransposeMatMult() tends to use much larger ctable than MatMatMult. Is your matrix symmetric? If so, MatMatMult() will use smaller ctable and require less communication.
Hong
