Enabling Accurate Performance Isolation on Hybrid Storage Devices in Cloud Environment

Hybrid storage devices have been widely deployed in cloud platforms to provide cost-efficient storage services. So the performance isolation on hybrid storage devices is important and necessary to ensure the quality-of-service (QoS) of cloud tenants. However, existing performance isolation techniques (e.g., the widely used cgroup) cannot provide accurate performance isolation on hybrid devices, usually leading to an unexpected throughput shrink than the user-specified value. In this paper, we propose a new Self-Adaptive Accurate Throttling (SAAT) method to achieve accurate performance isolation on hybrid storage devices. SAAT can give an accurate estimation of the throughput shift of existing solutions periodically according to the latest status of hybrid storage devices, and then adjust the assigned throughput of cgroup to achieve the accurate performance isolation. The experimental results exhibit that SAAT outperform the original cgroup method for 3.42 times on the difference of average throughput (DAT) between the target and the measured one, i.e., reducing DAT from 6.56% to 1.94%; in the meanwhile, SAAT reduces the Average Jitter of practical throughput from 6.62% to 5.25%.