Dimitris Skourtis: QBox - Guaranteeing I/O Performance on Black Box Storage Systems

Tuesday, May 29, 2012

Many storage systems are shared by multiple clients with different types of workloads and performance targets. To achieve performance targets without over-provisioning, a system must provide isolation between clients. Throughput-based reservations are challenging due to the mix of workloads and the stateful nature of disk drives, leading to low reservable throughput, while existing utilization-based solutions require specialized I/O scheduling for each device in the storage system.

QBox is a new utilization-based approach for generic black box storage systems that enforces utilization (and, indirectly, throughput) requirements and provides isolation between clients, without specialized low-level I/O scheduling. Our experimental results show that QBox provides good isolation and achieves the target utilizations of its clients.