VARIOUS DISK CONFIGURATIONS AND THEIR PERFORMANCE

摘要

In this paper we study several disk configurations and their performance. The proposed configurations are attempted to improve the disk response time by either doubling the number of heads per suspension or doubling the number of arms per disk. A simplified modeling approach is used to compare the effectiveness of these schemes. It is assumed that there is no cache in the subsystem and all other resources are abundant so that the channels and the disks are the only potential bottlenecks. M/G/1 queueing models are used to model the disk waiting time for the I/O requests. Based on this queueing model, the performances of the various configurations are compared. Previous versions of this work were done while the authors were with IBM