Disk scheduling

Description

This document discusses various disk scheduling algorithms:
- FCFS handles requests sequentially but suffers from the global zigzag effect.
- SSTF selects the request with the minimum seek time, reducing total head movement but risking starvation.
- SCAN and C-SCAN move the disk arm back and forth, providing more uniform wait times.
- LOOK and C-LOOK only move as far as the last request in each direction before reversing. Circular versions like C-SCAN are more fair but have larger total seek times. The optimal algorithm depends on disk load and request patterns.