It's taking so long because you are sleeping for .1 second between calling MPI_Test().
The TCP transport is only sending a few fragments of your message during each iteration through MPI_Test (because, by definition, it has to return "immediately"). Other transports do better handing off large messages like this to hardware for asynchronous progress. Additionally, in the upcoming v2.0.0 release is a non-default option to enable an asynchronous progress thread for the TCP transport. We're up to v2.0.0rc2; you can give that async TCP support a whirl, if you want. Pass "--mca btl_tcp_progress_thread 1" on the mpirun command line to enable the TCP progress thread to try it. > On May 4, 2016, at 7:40 PM, Zhen Wang <tod...@gmail.com> wrote: > > Hi, > > I'm having a problem with Isend, Recv and Test in Linux Mint 16 Petra. The > source is attached. > > Open MPI 1.10.2 is configured with > ./configure --enable-debug --prefix=/home/<me>/Tool/openmpi-1.10.2-debug > > The source is built with > ~/Tool/openmpi-1.10.2-debug/bin/mpiCC a5.cpp > > and run in one node with > ~/Tool/openmpi-1.10.2-debug/bin/mpirun -n 2 ./a.out > > The output is in the end. What puzzles me is why MPI_Test is called so many > times, and it takes so long to send a message. Am I doing something wrong? > I'm simulating a more complicated program: MPI 0 Isends data to MPI 1, > computes (usleep here), and calls Test to check if data are sent. MPI 1 Recvs > data, and computes. > > Thanks in advance. > > > Best regards, > Zhen > > MPI 0: Isend of 0 started at 20:32:35. > MPI 1: Recv of 0 started at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:35. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:36. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:37. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:38. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 1: Recv of 0 finished at 20:32:39. > MPI 0: MPI_Test of 0 at 20:32:39. > MPI 0: Isend of 0 finished at 20:32:39. > > <a5.cpp>_______________________________________________ > users mailing list > us...@open-mpi.org > Subscription: https://www.open-mpi.org/mailman/listinfo.cgi/users > Link to this post: > http://www.open-mpi.org/community/lists/users/2016/05/29085.php -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
