The authors seem to using the MPI package from Julia [1] so not something they did on their own. I didn't see any discussion on why MPI.jl is scales differently

The authors seem to using the MPI package from Julia [1] so not something they did on their own. I didn't see any discussion on why MPI.jl is scales differently than Fortran-MPI. Something for the MPI.jl developers to investigate. [1] https://github.com/robertstrauss/MPAS_Ocean_Julia/blob/main/scaling_test.jl https://github.com/robertstrauss/MPAS_Ocean_Julia/blob/main/...