Storage servers consume significant amounts of energy and are highly non-energy-proportional. Fortunately, researchers have proposed disks that adjust their rotation speeds based on utilization. However, these disks either pose significant engineering challenges (by having too many speeds) or adjust behavior only at a coarse grain (by having just two speeds). In this paper, we propose LogStore, a storage system that enables two-speed disks to achieve substantially increased energy proportionality and, consequently, lower energy consumption. Our evaluation with real I/O workloads shows that LogStore can decrease energy consumption significantly, even for very tightly provisioned servers, with a negligible impact on aggregate throughput.
['Wei Zheng', 'Ana Paula Centeno', 'Frederic T. Chong', 'Ricardo Bianchini']
LogStore: toward energy-proportional storage servers