Hi Alaa, Generally, for small number of processes, the performance of MPI_Bcast is usually equal to MPI_Isend/MPI_Recv, for large number of processes, broadcast should be better. Could you please try the lateat version of MPICH on you system ? MPICH2 is very old. Please also give us following information.Number of processesNumber of processes per nodeThe execution time of each algorithm Min Sent via my cell phone. -------- Original message -------- From: alaa nashar <[email protected]> Date: 9/7/2016 7:04 AM (GMT-06:00) To: [email protected] Subject: [mpich-discuss] MPI_Send and MPI_Bcast Dear all I have implemented the following two algorithms on my home Ethernet LAN containing 2/ and three heterogeneous devices using MPICH2. Algorithm1: 1- Root process reads the contents of an input array. 2- It then sends the array data to all other processes. 3- All processes including the root process perform specific computations on their array copies. 4- Once the computations within each process are finished, the generated arrays are directly written by the process that performed the computations to separate files. Algorithm2: Same as Algorithm 1 except step 2 is replace by: 2- Root process broadcast the array data to all other processes. The implementation of both algorithms work fine and give the expected results but Algorithm2 that uses MIPI_Bcast is slower than Algorithm1 that uses MPI_Send For my knowledge, MIPI_Bcast is faster than MPI_Send. Please, would you guide me to know if there is any conflict of misunderstand. Thanks a lot Alaa _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss