Latency Fairness Scheduling for Shared Storage Systems

Abstract

Providing latency support is an important problem for clustered storage systems. In this paper, we present Fair-EDF, a framework for latency guarantees in shared storage servers. It provides fairness control while supporting latency guarantees. Fair-EDF extends the pure earliest deadline first (EDF) scheduler by adding a controller to shape the workloads. Under overload it selects a minimal number of requests to drop and to choose the dropped requests in a fair manner. The evaluation results show Fair-EDF provides steady fairness control among a set of clients with different runtime behaviors.