Disk Scheduling These notes provide a clear, simple, and complete explanation of Disk Scheduling for Operating Systems. Perfect for B.Tech, BCA, MCA, and other computer science courses. The content is written in easy language, making it ideal for assignme

Disk Scheduling Algorithms

, Introduction
• Disk scheduling algorithms manage how data is read from and
written to a computer's hard disk. These algorithms help
determine the order in which disk read and write requests are
processed.
• Disk scheduling is also known as I/O Scheduling.
• The main goals of disk scheduling are to optimize the
performance of disk operations; reduce the time it takes to
access data and improve overall system efficiency.
• Common disk scheduling methods include First-Come,
First-Served (FCFS), Shortest Seek Time First (SSTF), SCAN,
C-SCAN, LOOK, and C-LOOK.

, • Importance of Disk Scheduling in Operating System
• Multiple I/O requests may arrive by different processes
and only one I/O request can be served at a time by
the disk controller. Thus other I/O requests need to
wait in the waiting queue and need to be scheduled.
• Two or more requests may be far from each other so
this can result in greater disk arm movement.
• Hard drives are one of the slowest parts of the
computer system and thus need to be accessed in an
efficient manner.