Quality of Service Support for Real-time Storage Systems

The performance and capacity of commodity computer systems have improved drastically in recent years. However, these systems still lack the support for real-time data access, which is required by an increasing number of emerging applications. In this paper we first present several important storage-bound real-time applications and classify their Quality of Service (QoS) requirements. We then survey the representative work on disk management in the areas of IO scheduling, admission control, and data placement. Finally, we present our approach for providing disk QoS in commodity systems and present key empirical results from the micro-benchmark-based evaluation of our QoS-enhanced Linux kernel.