Supercomputer Applications
MPI Projects, Part 1, Fall 2004

MPI Routines

1. Example programs:
   • helloWorldMPI.c
   • helloWorld2.c
   • passOneMPI.c
   • arrayMPI.c
   • bcast.c reduce.c

2. MPI Program Lab05, "HelloCluster.c"
   MPI_Init(), MPI_Comm_size() , MPI_Comm_rank(), MPI_Finalize() MPI_COMM_WORLD (scroll down to "Communicators")

3. MPI Program Lab06, share.c
   --Input a number with scanf, broadcast this value to other "nodes"/processes
   uses:
   MPI_Send(), and MPI_Recv() (Vers. 1)
   MPI_Bcast() (Vers. 2)
   also see MPI Data types
   NOTE: Place the call to MPI_Bcast outside of the "if (rank == 0)" block:

            if (rank == 0) {
   	      scanf( ... );
   	  }
   	  MPI_Bcast( ... );  //MPI_Bcast is like a combination send/receive,
   	                     //so each process needs it
   	

4. MPI Program Lab07, DinnerParty.c
   Use MPI_Send(), and MPI_Recv(), INSTEAD OF MPI_Bcast()
   Sample Output:
   mpirun N lab02
   Process 0, Sending out random int 406999 to process 1
   Process 2 received: 1252750, mysalary=380245, sending out 1632995 to process 3
   Process 3 received: 1632995, mysalary=600007, sending out 2233002 to process 4
   Process 1 received: 406999, mysalary=845751, sending out 1252750 to process 2
   Process 0 received 3014004, mySalary=157838, average salary=$460807.17
   Process 4 received: 2233002, mysalary=618007, sending out 2851009 to process 5
   Process 5 received: 2851009, mysalary=162995, sending out 3014004 to process 0

5. MPI Program Lab08, IntervalSlicing.c - Calculate Pi,
   --parallelize the program "gregory.c"
   Use MPI_Reduce() to sum data that is local to each process

6. MPI Program Lab09, Parallel Programming Application - Array Search
   --a parallelized search of a large array for a target value

7. MPI Resources and Sample Programs
   • Introduction to MPI programming
   • Introductory Slides on MPI, by William Gropp
   • A Short Overview of MPI Concepts, by William Gropp
   • MPI Exercises, Pt.1
   • Intermediate Level MPI programming