An Optimal Restricted Multi-Headed Disk System

Abstract

Disk system is important to operating system and database management system. Now, the multi-headed disk system is commercially available. There are many such disk systems used in our computers to improve the system performance. In this paper, we consider a restricted multi-headed disk system. The disk heads in this system are locked in a fixed number of cylinders, and they are distributed on the disk surface equally. We call these heads restricted since these disk heads must remain within the disk surface. According to our analysis , this disk system is optimal based upon the amortized complexity. Moreover, we obtain that this disk system performs more than k times as well as a system with only one head. Here k is the number of the disk heads used in our multi-headed disk system. This result matches the conclusions of the previous studies in which multi-headed disk systems have been analyzed based on some probability models.