Abstract:

Heterogeneous multicore processors mostly consist of highperformance big cores and energyefficient small cores. Proper scheduling on such kind of processors can improve resource utilization and reduce energy consumption effectively. Fairnessaware scheduling proposed previously does not take DVFS into account. However, processors supporting DVFS become more and more common. It is necessary to extend fairnessaware scheduling to processors with multiple frequency/voltage states on each core. In this paper, we propose a scheduling on heterogeneous multicore processors which can reduce the energy consumption of the workload by keeping both the fairness of all threads and the total power of the processor satisfying the preset threshold. We propose a calculation method for the fairness among cores with multiple frequency/voltage states, and improve the existing performance prediction models which can estimate the performance of a thread for all configurations using hardware counters collected on the current configuration. Then the best scheduling policy is chosen, which can not only satisfy the fairness and the power threshold, but also maximize the energy efficiency at the same time. Some experiments are done with the Odroid XU3 development board and more experiments with Sniper simulator. Experimental results show that compared with the static, DVFSonly, swaponly scheduling, the proposal can reduce energy consumption obviously while the total running time is almost not affected.

Key words: heterogeneous multicores;DVFS;fairness;energy consumption;thread scheduling