CAREER: Building Virtual Devices with QoS Assurance in a Consolidated Storage Infrastructure

Wayne State University, Detroit MI

Investigators

Abstract

A growing and inevitable trend in the use and management of storage resources is the consolidation of distributed storage into a large data center to reduce the rapidly growing administration cost and to improve resource utilization. Despite its compelling advantages and years of efforts on research and product development, a critical challenge in turning this promising technology into reality remains to be addressed, which is that the quality of the I/O services (QoS) cannot be conveniently presented and efficiently guaranteed for users who outsource their dedicated storages to the shared system. To this end, a performance interface, or specification of required service quality, must be able to allow a diverse set of users to easily relate each of their I/O QoS requirements to their respective application performance and enable efficient system implementation to meet the QoS requirements. Currently, the QoS requirements are usually presented in the form of service-level agreements (SLAs) to bound latency and throughput of I/O requests. SLA is not suitable for I/O requests from application servers to storage servers because users have difficulties in using the performance interface and resources allocation can be misguided by the SLA measures, which do not consistently reflect users' resource demands. To address this critical issue, the investigator will develop a reference (or virtual) storage device as performance interface and will implement consolidated storage service based on the interface. In this way, a user is guaranteed to receive an I/O service whose quality is at least as good as that on the reference system regardless of variations and instantaneous changes of data access patterns. The research project aims to remove the significant barrier for users and system administrators to communicate I/O performance requirements and pave the road to wide acceptance of the storage consolidation technology.