Manageable storage via adaptation in WiND

The key to storage manageability is adaptation. In traditional storage systems, adaptation is performed by a human administrator who must assess problems and then manually adjust various knobs and levers to bring the behavior of the system back to an acceptable level. Future storage systems must themselves adapt and, in doing so, reduce the need for manual intervention. In this paper, we describe the Wisconsin Network Disks (WiND) project, wherein we seek to understand and develop the key adaptive techniques required to build a truly manageable network-attached storage system. WiND gracefully and efficiently adapts to changes in the environment, reducing the burden of administration and increasing the flexibility and performance of storage for an eclectic range of clients. In particular, WiND automatically adapts to the addition of new disks to the system, the failure or erratic performance of existing disks and changes in client workload and access patterns.