Instrumentation for a massively parallel MIMD application

Abstract

This paper describes an application implemented on a simulated machine called Horizon. One purpose of this study is to investigate some of the features of a possible future machine (or class of machines) with a view toward deciding, early on in the research cycle, where problems may come up, what features should be added or strengthened, and what proposed features seem to be unnecessary. Another purpose is to learn more about how to program, instrument and debug a shared memory, massively parallel MIMD computer, and to begin to answer some of the questions: What tools does a programmer need to debug this type of machine? How can a programmer know if the machine is performing well? How can bottlenecks be identified? How can the massive amount of instrumentation information be condensed and presented to a user in a way that makes sense?