Sending and Receiving 2D Arrays using MPI

Problem:

You have a large 2D matrix that requires processing across multiple nodes using MPI. The only communication between nodes involves sharing edge values after each time step.

Approach:

Your proposed approach, outlined in the question, is suitable for this problem. The following code segments illustrate the suggested implementation:

// (assume A is a 2D array)
if (myrank == 0) {
  for (i = 0; i 
Additional MPI Functions:

• MPI_Allgather: Gathers data from all processors into a buffer accessible to all processors. Useful for collecting a distributed array onto a single processor.
• MPI_Alltoall: Provides a complete exchange of data between all processors.
• MPI_Sendrecv: A convenient function that combines a send and receive operation into a single call.
• MPI_Buffer_attach: Attaches a buffer to a process, without needing to explicitly allocate memory for it.

Considerations:

• Contiguous memory allocation is recommended for 2D arrays to simplify MPI communication.
• MPI_Barrier ensures synchronization between processes, but it can be replaced with non-blocking alternatives like MPI_Wait or MPI_Test.
• Blocking sends and receives are used here, but non-blocking options are available for enhanced efficiency.