PollO: Polling-aware On-demand Governor for Improving Power Efficiency

Efficient power management is one of the most important requirements for modern mobile computing devices. To satisfy it, the Linux kernel provides CPU governors which can adjust the CPU frequency. Meanwhile, as high-performance storage devices being matured, vendors have begun to employ them into mobile devices. To sufficiently exploit this high performance of storage devices, we can use polling-based I/O service mechanism, because it can perform better than conventional methods. However, polling-based I/O service mechanism does not have benefit in power consumption, and traditional CPU governors do not consider this characteristic of polling-based I/O service. In this paper, we introduce Polling-aware Ondemand governor, called PollO governor, which improves the power efficiency while ensuring comparable I/O performance. Our experimental results show that PollO governor achieves 26.93% lower power consumption without a performance drop.