I’ve browsed several tutorials and articles found on Fortran Wiki and elsewhere and got into confusion mentioned as the B3 question in this topic.
Some articles (e.g. Shterenlikht, A. and L. Cebamanos (2018). Cellular automata beyond 100k cores: MPI vs Fortran coarrays) shows that a coarray Fortran program can be run on multiple parallel nodes, i.e. separate, although interconnected with a fast nestwork, machines.
Now all the tutorials I have found on coarrays, as well as my naive, simple tests using gfortran and OpenCoarrays, ended up with executables suited for execution in Shared Memory environment, i.e. multiple threads running on on a single, yet multi-core, machine.
Could somebody point me to a simple cheat sheet/tutorial on how to do it on multiple nodes, without digging into some hundreds of pages MPI manuals etc.? Am I right assuming that coarrays in modern Fortran should, in principle, allow that without need for adding all MPI function calls to the code?