2016年1月18日 · I have found this IBM link and this question MPI - one function for MPI_Init and MPI_Init_thread. I am interesting only in C, if that matters. I am interesting only in C, if that matters. The description is the same for both functions:

2010年4月15日 · MPI_Init(&argc, &argv) argc = 3 and myparam1 is at argv[1] and myparam2 is at argv[2] Apparently this is outside the standard, but I've tested it on linux mpich and it certainly seems to be the case.

In most MPI implementations on Linux/Windows/Mac OSX, when you call MPI_Init(&argc, &argv), the argument list is modified just as if you had run the serial problem as program 10 10; it eats the argument list up to the executable, which can potentially contain any number of options to the mpirun command itself.

2012年7月28日 · Note that MPI_Init() is just a regular library call as any other library call. It doesn't change the content of user memory - it only makes the multitude of running MPI processes aware of one another and enables them to communicate with each other, thus enabling them to work collectively in order to solve the particular problem.

2012年1月27日 · MPI_Init initialises the environment needed to make MPI calls. It has little to do with fork() or mpiexec. At the point when MPI_Init is called all MPI instances/processes would have already started. You don't call it more than once simply because the initialisation process should only be done once and repeated calls may lead to errorneous ...

2009年9月10日 · Then MPI_INIT_THREAD will return provided = MPI_THREAD_MULTIPLE, irrespective of the value of required; a call to MPI_INIT will also initialize the MPI thread support level to MPI_THREAD_MULTIPLE. Suppose, on the other hand, that an MPI program has been started so that all four levels of thread support are available.

2012年11月14日 · You've basically got the right solution, so I'll just confirm. It is in fact erroneous to call MPI_Init and MPI_Finalize multiple times, and if you have an entity that calls these internally on creation/destruction, then you can only instantiate that entity once. If you want to create multiple instances, you'll need to change the entity to do ...

1997年8月6日 · Once this routine is called, no MPI routine (even MPI_INIT) may be called. The user must ensure that all pending communications involving a process completes before the process calls MPI_FINALIZE. MPI_INITIALIZED( flag ) [ OUT flag] Flag is true if MPI_INIT has been called and false otherwise. int MPI_Initialized(int *flag)

2015年6月4日 · MPI_INIT_THREAD(REQUIRED, PROVIDED, IERROR) INTEGER REQUIRED, PROVIDED, IERROR . Advice to users. In C, the passing of argc and argv is optional, as with MPI_INIT as discussed in Section Startup . In C, null pointers may be passed in their place. (End of advice to users.) This call initializes MPI in the same way that a call to MPI_INIT would ...

2012年7月10日 · MPI libraires usually come with compiler wrappers like mpicc, mpic++, etc. that one normally uses to compile and link MPI program.