Falcon: On-line Monitoring and Steering of Large-scale Parallel Programs 1

{ Falcon is a system for on-line monitoring and steering of large-scale parallel programs. The purpose of such interactive steering is to improve its performance or to aaect its execution behavior. The Falcon system is composed of an application-speciic on-line monitoring system, an interactive steering mechanism, and a graphical display system. In this paper, we present a framework of the Falcon system, its implementation, and evaluation of the system performance. A complex sample application { a molecular dynamics simulation program (MD) { is used to motivate the research as well as to evaluate the performance of the Falcon system.