Dear Christian, Thanks for the idea. I play with Ssends a little in the other reply. Best regards. Alexander -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Christian Siebert Sent: Friday, October 17, 2008 2:42 PM To: MPI-3 Collective Subgroup Discussions Subject: Re: [mpi3-coll] Non-blocking Collectives Proposal Draft Dear Alexander, as Rich pointed out, your example will not deadlock (try to understand his good explanation). I think that your progression question is not really related to nonblocking collectives. The same question could be asked with an example using MPI-1: process 0 process 1 --------- --------- MPI_Irecv(.., req) MPI_Barrier(comm) MPI_Barrier(comm) MPI_Ssend(..) MPI_Bcast(..) MPI_Bcast(..) MPI_Wait(req, ..) The barrier only ensures that the send gets started after the incompleted Irecv returned to the user (to simulate the outstanding Ibarrier). Although the broadcast has nothing to do with the Irecv(), it will still ensure the required progress. Best regards, Christian -- Christian Siebert, Dipl.-Inf. Research Associate NEC Laboratories Europe, NEC Europe Ltd. Rathausallee 10, D-53757 Sankt Augustin, Germany Phone: +49 (0) 2241 - 92 52 44 Fax: +49 (0) 2241 - 92 52 99 (Registered Office: 1 Victoria Road, London W3 6BL, 2832014) _______________________________________________ mpi3-coll mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi3-coll --------------------------------------------------------------------- Intel GmbH Dornacher Strasse 1 85622 Feldkirchen/Muenchen Germany Sitz der Gesellschaft: Feldkirchen bei Muenchen Geschaeftsfuehrer: Douglas Lusk, Peter Gleissner, Hannes Schwaderer Registergericht: Muenchen HRB 47456 Ust.-IdNr. VAT Registration No.: DE129385895 Citibank Frankfurt (BLZ 502 109 00) 600119052 This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.