On Sat, Jul 17, 2010 at 07:49:21AM -0400, Jeff Squyres wrote: > On Jul 17, 2010, at 4:13 AM, Anton Shterenlikht wrote: > > > Sorry, just to be absolutely clear, are you saying > > that even though only one process in the communicator > > is calling Bcast, the call will be made on all > > processes? > > MPI does not magically cause all processes to call MPI_Bcast behind the > scenes for you. You must ensure that every process in the communicator > explicitly invokes MPI_Bcast. You can do whatever logic you want (to include > "if" blocks, etc.) as long as they all call MPI_Bcast. > > To be clear: all MPI collective operations must be explicitly invoked by > every process in the target communicator.
Jeff, many thanks. Now I'm very clear indeed. -- Anton Shterenlikht Room 2.6, Queen's Building Mech Eng Dept Bristol University University Walk, Bristol BS8 1TR, UK Tel: +44 (0)117 331 5944 Fax: +44 (0)117 929 4423
