How to Build Scalable On-Chip ILP Networks for a Decentralized Architecture

Abstract

The era of billion transistors-on-a-chip is creating a completely different set of design constraints, forcing radically new microprocessor archiecture designs. This paper examines a few of the possible microarchitectures that are capable of obtaining scalable ILP performance. First, we observe that the network that interconnects the processing elements is the critical design point in the microarchitecture. Next, we characterize four fundamental properties that have to be satisfied by the interconnection network. Next, we provide case studies of two different networks that satisfy these properties. Finally, a detailed evaluation of these networks is presented to highlight the scalability and performance of these microarchitectures. We show that by using compile time information, we can build simpler networks and use them efficiently.