I updated the branch and made a PR. I tried to do MPI_SUM on MPI_CHAR. We do not have UnpackAdd on this type (we are right). But unfortunately, MPICH's MPI_Reduce_local did not report errors (it should) so we did not generate an error either.
--Junchao Zhang On Thu, Apr 4, 2019 at 10:37 AM Jed Brown <j...@jedbrown.org<mailto:j...@jedbrown.org>> wrote: Fande Kong via petsc-users <petsc-users@mcs.anl.gov<mailto:petsc-users@mcs.anl.gov>> writes: > Hi Jed, > > One more question. Is it fine to use the same SF to exchange two groups of > data at the same time? What is the better way to do this This should work due to the non-overtaking property defined by MPI. > Fande Kong, > > ierr = > PetscSFReduceBegin(ptap->sf,MPIU_INT,rmtspace,space,MPIU_REPLACE);CHKERRQ(ierr); > ierr = > PetscSFReduceBegin(ptap->sf,MPI_CHAR,rmtspace2,space2,MPIU_REPLACE);CHKERRQ(ierr); > Doing some calculations > ierr = > PetscSFReduceEnd(ptap->sf,MPIU_INT,rmtspace,space,MPIU_REPLACE);CHKERRQ(ierr); > ierr = > PetscSFReduceEnd(ptap->sf,MPI_CHAR,rmtspace2,space2,MPIU_REPLACE);CHKERRQ(ierr);
