Trading Capacity for Performance in a Disk Array


X. Yu, B. Gum, Y. Chen, R. Y. Wang, K. Li, A. Krishnamurthy, and T. E. Anderson. Trading Capacity for Performance in a Disk Array. Proc. Fourth Symposium on Operating Systems Design and Implementation. October 2000.


A variety of performance-enhancing techniques, such as striping, mirroring, and rotational data replication, exist in the disk array literature. Given a fixed budget of disks, one must intelligently choose what combination of these techniques to employ. In this paper, we present a way of designing disk arrays that can flexibly and systematically reduce seek and rotational delay in a balanced manner. We give analytical models that can guide an array designer towards optimal configurations by considering both disk and workload characteristics. We have implemented a prototype disk array that incorporates the configuration models. In the process, we have also developed a robust disk head position prediction mechanism without any hardware support. The resulting prototype demonstrates the effectiveness of the configuration models.


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© 2000 Randy Wang    (rywang.public@gmail.com)