did you try to start the program with the --mca coll ^inter switch that I mentioned? Collective dup for intercommunicators should work, its probably again the bcast over a communicator of size 1 that is causing the hang, and you could avoid it with the flag that I mentioned above.
Also, if you could attach your test code, that would help in hunting things down. Thanks Edgar On 4/4/2012 2:18 PM, Thatyene Louise Alves de Souza Ramos wrote: > Hi there. > > I've made some tests related to the problem reported by Rodrigo. And I > think, I'd rather be wrong, that /collective calls like Create and Dup > do not work with Inter communicators. I've try this in the client group:/ > > *MPI::Intercomm tmp_inter_comm;* > * > * > *tmp_inter_comm = server_comm.Create (server_comm.Get_group().Excl(1, > &rank));* > * > * > *if(server_comm.Get_rank() != rank)* > *server_comm = tmp_inter_comm.Dup();* > *else* > *server_comm = MPI::COMM_NULL;* > * > * > The server_comm is the original inter communicator with the server group. > > I've noticed that the program hangs in the Dup call. It seems that the > tmp_inter_comm created without one process still has this process, > because the other processes are waiting for it call the Dup too. > > What do you think? > > On Wed, Mar 28, 2012 at 6:03 PM, Edgar Gabriel <gabr...@cs.uh.edu > <mailto:gabr...@cs.uh.edu>> wrote: > > it just uses a different algorithm which avoids the bcast on a > communicator of 1 (which is causing the problem here). > > Thanks > Edgar > > On 3/28/2012 12:08 PM, Rodrigo Oliveira wrote: > > Hi Edgar, > > > > I tested the execution of my code using the option -mca coll ^inter as > > you suggested and the program worked fine, even when I use 1 server > > instance. > > > > What is the modification caused by this parameter? I did not find an > > explanation about the utilization of the module coll inter. > > > > Thanks a lot for your attention and for the solution. > > > > Best regards, > > > > Rodrigo Oliveira > > > > On Tue, Mar 27, 2012 at 1:10 PM, Rodrigo Oliveira > > <rsilva.olive...@gmail.com <mailto:rsilva.olive...@gmail.com> > <mailto:rsilva.olive...@gmail.com > <mailto:rsilva.olive...@gmail.com>>> wrote: > > > > > > Hi Edgar. > > > > Thanks for the response. I just did not understand why the Barrier > > works before I remove one of the client processes. > > > > I tryed it with 1 server and 3 clients and it worked properly. > After > > I removed 1 of the clients, it stops working. So, the removal is > > affecting the functionality of Barrier, I guess. > > > > Anyone has an idea? > > > > > > On Mon, Mar 26, 2012 at 12:34 PM, Edgar Gabriel > <gabr...@cs.uh.edu <mailto:gabr...@cs.uh.edu> > > <mailto:gabr...@cs.uh.edu <mailto:gabr...@cs.uh.edu>>> wrote: > > > > I do not recall on what the agreement was on how to treat > the size=1 > > > > > > > > > > > > _______________________________________________ > > users mailing list > > us...@open-mpi.org <mailto:us...@open-mpi.org> > > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > _______________________________________________ > users mailing list > us...@open-mpi.org <mailto:us...@open-mpi.org> > http://www.open-mpi.org/mailman/listinfo.cgi/users > > > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users -- Edgar Gabriel Associate Professor Parallel Software Technologies Lab http://pstl.cs.uh.edu Department of Computer Science University of Houston Philip G. Hoffman Hall, Room 524 Houston, TX-77204, USA Tel: +1 (713) 743-3857 Fax: +1 (713) 743-3335
signature.asc
Description: OpenPGP digital signature
