Decoupled speed scaling: Analysis and evaluation

In this paper, we introduce the notion of decoupled speed scaling, wherein the speed scaling function is completely decoupled from the scheduling policy used in a simple single-server computer system. As an initial result, we first demonstrate that the Fair Sojourn Protocol (FSP) scheduling policy does not work properly with coupled (native) speed scaling, but that it can and does work well with decoupled speed scaling. We then compare the performance of PS, SRPT, and FSP scheduling policies under decoupled speed scaling, and demonstrate significant advantages for FSP. Our simulation results suggest that it might be possible to simultaneously achieve fairness, robustness, and near optimality with decoupled speed scaling.