Optimal data placement on disks: a comprehensive solution for different technologies

The problem of optimally placing data on disks (ODP) to maximize disk-access performance has long been recognized as important. Solutions to this problem have been reported for some widely available disk technologies, such as magnetic CAV and optical CLV disks. However, important new technologies such as multizoned magnetic disks, have been recently introduced. For such technologies no formal solution to the ODP problem has been reported. In this paper, we first identify the fundamental characteristics of disk-device technologies which influence the solution to the ODP problem. We develop a comprehensive solution to the problem that covers all currently available disk technologies. We show how our comprehensive solution can be reduced to the solutions for existing disk technologies, contributing thus a solution to the ODP problem for multizoned disks. Our analytical solution has been validated through simulations and through its reduction to the known solutions for particular disks. Finally, we study how the solution for multizoned disks is affected by the disk and data characteristics.