Power Minimization under QoS Constraints

Abstract

QoS has been often addressed in multimedia, video, and networking research communities, but rarely in the design community. Our goal is to introduce the first system design technique for comprehensive quality-of-service (QoS) low power synthesis. Specifically, we study how to efficiently exploit the trade-o between the system cost and energy consumption in real-time systems that address packet-based multimedia transmission and processing. We first introduce a system of techniques that minimizes energy consumption of stream-oriented applications under two main QoS metrics: latency and synchronization. Speci cally, we study how multiple voltages can be used to simultaneously satisfy hardware requirements and minimize power consumption, while preserving the requested level of QoS, in this case satisfying latency and synchronization requirements. We have developed a provably optimal polynomial time o -line algorithm for multiple volt- age scheduling of single and multiple processes. The o -line algorithm provides lower bounds on achievable power minimization and can be used as a starting point for the development and evaluation of an on-line approach. The effectiveness of the algorithm is demonstrated on a number of multimedia benchmarks.