Inside the Message Passing Interface

Chapter 1 Overview

The implementation process of a Message Passing Interface library is guided by laser focused dedication to performance. This dedication permeates the MPI standard, it drives the advices to implementors contained therein, it forces an implementor to think thrice about every bit and byte, every conditional operation, and extra argument added to the source code, because all seemingly desirable extras result in additional nanoseconds in the critical code path. Yes, this is not a typo. We are going to deal in nanoseconds in this book. A thousand of them will make a whole microsecond, and this will soon seem to you like walking instead of flying, because characteristic latencies associated with the shared memory and modern networks ...