The advantage of the Buffer interface is that mpi4py can take advantage of it. (Essentially making the whole of MPI available) I don’t know of a way to use it directly with address and length. Maybe using custom DataTypes, but I’d need to investigate that.
Since I can afford a hacky solution (only need send/recv), I’ll try that while waiting for THDP. In any case, I’ll keep this thread up-to-date.