On Fri, May 22, 2020 at 4:34 PM Lucas Banting <[email protected]> wrote:
> Hello, > > I am converting a serial code to parallel in fortran with petsc. I am > using the DMDA to manage communication of the information that used to be > in old two-dimensional fortran arrays. > > I noticed when using DMLocalToLocalBegin/End, not all the ghost values in > the array at the DM_BOUNDARY_GHOSTED area is updated. Is this expected > behaviour? > I believe so. GHOSTED is user managed space. We do not touch it. > I read through this thread: > https://lists.mcs.anl.gov/mailman/htdig/petsc-users/2016-May/029252.html > and saw someone had a similar question, but the answer was not clear to me. > > If this is expected behaviour, how should I instead update these values in > my arrays? I was using DM_BOUNDARY_GHOSTED as I needed the extra ghost > cells for some subroutines, but I do not need them in my matrix from > DMCreateMatrix. > You fill them in the local vector. Thanks, Matt > I am using Petsc 3.12.4 and open MPI 3.1.4. > > Thanks, > > Lucas Banting > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>
