Metrics and task scheduling policies for energy saving in multicore computers

In this paper, we have proposed three new metrics, Speedup per Watt (SPW), Power per Speedup (PPS) and Energy per Target (EPT), to guide task schedulers to select the best task schedules for energy saving in multicore computers. Based on these metrics, we have proposed the novel Sharing Policies, the Hare and the Tortoise Policies, which have taken into account parallelism and Dynamic Voltage Frequency Scaling (DVFS) in their schedules. Our experiments show that, on a modern multicore computer, the Hare Policy can save energy up to 72% in a system with low utilization. On a busier system the Sharing Policy can make a saving up to 20% of energy over standard scheduling policies.