Pardon my ignorance, but how is the Alltoallv used? In Parallel HOP, I communicate arrays that are large fractions of a GB in size with no problem using un-pickled methods. I looked and it appears that Alltoallv is a not pickling comm, is this correct?
Hi Stephen, No, you're totally right, it's used to communicate a single array via direct buffers at a time. So if you're projecting Density and Temperature, the alltoall would be something like: calculate_sizes calculate_offsets for field in "px" "py" "pdx" "pdy" "Density" "Temperature: create_full_array alltoall(sizes, offsets, field, full_array) I'm not sure what the deal is with OpenMPI on Ranger. I'll see if I can replicate this and dig a bit deeper on Ranger tomorrow... -Matt