Abstract

A central problem in building large scale parallel machines is the design of the interconnection network. Interconnection network design is largely constrained by packaging technology. We start with a generic set of packaging restrictions and evaluate di erent network organizations under a random tra c model. Our results indicate that customizing the network topology to the packaging constraints is useful. Some of the general principles that arise out of this study are: 1) Making the networks denser at the lower levels of the packaging hierarchy has a signi cant positive impact on global communication performance, 2) It is better to organize a xed amount of communication bandwidth as a smaller number of high bandwidth channels, 3) Providing the processors with the ability to tolerate latencies (by using multithreading) isvery useful in improving performance.

Citations