ABSTRACT
Computer system designers face two challenges: energy and performance. The spectrum of system design considerations ranges from ultrahigh performance on one side, in which energy consumption is not a limiting factor, all the way to ultralow power design, where performance expectations are very low. The middle of the range is occupied by systems where both power and performance play a role in system design. Portable system designers are faced with a user demand for performance, functionality, and better user interfaces along with a longer battery life. Designers of servers and desktop systems focus almost entirely on performance, since energy usually is not a constrained resource. However, this trend has started to change since researchers have realized the positive financial and environmental implications of energy conservation for stand-alone servers and server clusters [1-4]. The challenge of designing energy-efficient systems lies in understanding the role of user interaction in energy consumption and in providing an energy-performance schedule that adequately accommodates user demand. Furthermore,
system performance can be tailored to a user’s pattern of interaction and its energy-performance schedule optimized.
