For decades, the high-performance computing (HPC) community has focused on performance, where performance is defined as speed. To achieve better performance per compute node, microprocessor vendors have not only doubled the number of transistors (and speed) every 18-24 months, but they have also doubled the power densities. Consequently, keeping a large-scale HPC system functioning properly requires continual cooling in a large machine room, thus resulting in substantial operational costs. Furthermore, the increase in power densities has led (in part) to a decrease in system reliability, thus leading to lost productivity. To address these problems, we propose a power-aware algorithm that automatically and transparently adapts its voltage and frequency settings to achieve significant power reduction and energy savings with minimal impact on performance. Specifically, we leverage a commodity technology called “dynamic voltage and frequency scaling” to implement our power-aware al...