What is the scan disk scheduling algorithm?

Overview

The scan is a disk scheduling algorithm that serves requests generated by memory management unit.

• It is also called an elevator algorithm.
• In this algorithm read and write head has to move in one direction and fulfill all the requests until we move to the end of the disk.
• In this algorithm, the direction matters to serve requests.

Example

Let’s consider a disk with 200 tracks(0-199), a request queue containing track numbers [82,170,43,140,24,16,190], and the current position of read-write head=50. The requirement is to find the total number of track movements in cylinders.