According to the mpi_finalize documentation, a call to mpi_finalize terminate all processes. I have ran into this problem before where one process calls mpi_finalize before other processes reach the same line of code and cause errors/hang ups. Put a mpi_barrier(mpi_comm_world) before mpi_finalize would do the trick.
On Mon, Jan 31, 2011 at 11:40 PM, abc def <cannonj...@hotmail.co.uk> wrote: > Hello, > > I'm having trouble with some MPI programming in Fortran, using openmpi. > It seems that my program doesn't work unless I print some unrelated text to > the screen. For example, if I have this situation: > > *** hundreds of lines cut *** > IF (irank .eq. 0) THEN > CALL print_results1(variable) > CALL print_results2(more_variable) > END IF > print *, "done", irank > CALL MPI_FINALIZE(ierr) > END PROGRAM calculation > > The results are not printed unless I include this "print done irank" > penultimate line. > Also, despite seeing that all ranks reach the print statement, the program > hangs, as if they have not all reached MPI_FINALIZE. > > Can anyone help me? Why does it do this? > > I also had many times where the program would crash if I didn't include a > print statement in a loop. I've been doing Fortran programming for a while, > and this is my nightmare debugging scenario since I've never been able to > figure out why the simple printing of statements magically fixes the > program, and I usually end up having to go back to a serial solution, which > is really slow. > > If anyone might be able to help me, I would be really really grateful!! > > Thank you. > > Tom > > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users > -- David Zhang University of California, San Diego
