Portability is an important concern give the short life time of current parallel computer systems.
The following sections describes MPI in greater detail and illustrates its use with two extremely simple examples written in Fortran and C. 2. These function implement communication operations among the multiple processors cooperating on a computation. The MPI model is a message passing model where processors at both the message source and the message destination must actively participate in the communication operation. MPI Collective communication is used to exchange data among several processors. Examples of collective operations are barriers synchronizations, reductions, and broadcasts.