Multiple completions


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It is often desirable to wait on multiple requests. An example is a master/slave program, where the master waits for one or more slaves to send it a message.


  • MPI_Waitall(count, array_of_requests, array_of_statuses)
  • MPI_Waitany(count, array_of_requests, index, status)
  • MPI_Waitsome(incount, array_of_requests, outcount, array_of_indices, array_of_statuses)
    There are corresponding versions of test for each of these.

    127 The MPI_WAITSOME and MPI_TESTSOME may be used to implement master/slave algorithms that provide fair access to the master by the slaves.



    Up: Buffering issues Next: Fairness Previous: MPI's Non-Blocking Operations