LEneS: task scheduling for low-energy systems using variable supply voltage processors

The work presented in this paper addresses minimization of the energy consumption of a system during system-level design. The paper focuses on scheduling techniques for architectures containing variable supply voltage processors, running dependent tasks. We introduce our new approach for low-energy scheduling (LEneS) and compare it to two other scheduling methods. LEneS is based on a list-scheduling heuristic with dynamic recalculation of priorities, and assumes a given allocation and assignment of tasks to processors. Our approach minimizes the energy by choosing the best combination of supply voltages for each task running on its processor. The set of experiments we present shows that, using the LEneS approach, we can achieve up to 28% energy savings for the tightest deadlines, and up to 77% energy savings when these deadlines are relaxed by 50%.