How to optimize communication

An interesting feature that is provided by MPI concerns the virtual topologies. As already noted, all the communication functions (point-to-point or collective) refer to a group of processes. We have always used the MPI_COMM_WORLD group that includes all processes. It assigns a rank 0 to n-1 for each process that belongs to a communicator of the size n. However, MPI allows us to assign a virtual topology to a communicator. It defines a particular assignment of labels to the different processes. A mechanism of this type permits you to increase the execution performance. In fact, if you build a virtual topology, then every node will communicate only with its virtual neighbor, optimizing the performance.

For example, ...

Get Python Parallel Programming Cookbook now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.