A computer-architecture approach to thermal management in computer systems: opportunities and challenges

Cooling costs for notebook, desktop, and server computer systems are rising exponentially as power densities for high-performance chips continue to double every three years. Research has led to a range of advances in modeling and design of thermal packaging and circuit boards. Yet a major front that has been absent is thermal design in the computer architecture domain, where processor utilization, the interleaving of different computation processes, and the flow of instructions through the CPU are controlled. The architecture domain presents a rich opportunity for thermal management that complements other advances by controlling temperature at runtime in response to the dynamic behavior of the computer's current workload. This paper describes a compact modeling algorithm that is appropriate for this domain, presents some architecture techniques for runtime thermal management, and describes some interesting problems that remain to be solved.