Chained declustering: load balancing and robustness to skew and failures

Abstract

There has been considerable research concerning the use of arrays of disks in solving I/O bottleneck problems, where high availability of data is achieved through some form of data redundancy, e.g. mirroring. This paper investigates the degree to which a dynamic load balancing disk scheduling algorithm in conjunction with chained declustering, an alternative to the classical mirroring scheme, can respond robustly to variations in workload and disk failures. Specifically, it defines and investigates the behavior of two dynamic scheduling algorithms under various workload distributions and disk failure. It demonstrates that using a simple dynamic scheduling algorithm can greatly improved the average response time compared with static load balancing.<>