On Aug 10, 2018, at 6:27 PM, Diego Avesani <diego.aves...@gmail.com> wrote: > > The question is: > Is it possible to have a barrier for all CPUs despite they belong to > different group? > If the answer is yes I will go in more details.
By "CPUs", I assume you mean "MPI processes", right? (i.e., not threads inside an individual MPI process) Again, this is not quite a specific-enough question. Do the different groups (and I assume you really mean communicators) overlap? Are they disjoint? Is there a reason MPI_COMM_WORLD is not sufficient? There are two typical ways to barrier a set of MPI processes. 1. Write your own algorithm to do sends / receives -- and possibly even collectives -- to ensure that no process leaves the barrier before every process enters the barrier. 2. Make sure that you have a communicator that includes exactly the set of processes that you want (and if you don't have a communicator fitting this description, make one), and then call MPI_BARRIER on it. #2 is typically the easier solution. -- Jeff Squyres jsquy...@cisco.com _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users
