INSPIRE : A general purpose network simulator generating system for massively parallel processors

In this paper, we describe a general purpose network simulator generation system INSPIRE (Interconnection Network Simulator with Programmable Interaction and Routing for performance Evaluation), for massively parallel processing systems. In this system, a user describes various characteristics of the target network, for instance, network resources, network topology, and routing algorithm, in a dedicated language called NDL (Network Description Language). A user also can describe the behavior of PU's (Processing Units) in C language with procedural manner to simulate not only simple message transfer patterns but also actual application. The network speci cation le in NDL is translated into a C language source le, then combined with PU behavior description le and the kernel object code for INSPIRE to create a dedicated network simulator. It is executed automatically and it helps reducing a large man-power for writing simulators for various kinds of network and PU behavior. A simulator created by INSPIRE simulates the behavior of all PU's, message sent/received by PU's, and message transfer and con ict on the network. Finally, various statistics on message passing and PU behavior are shown as the simulation result. We have implemented INSPIRE on UNIX workstations, and con rmed that the execution speed of generated simulator is enough high compared with dedicated simulators. We also con rmed that NDL is powerful enough to describe various kinds of direct and indirect network topologies.