Question

Which disk scheduling algorithm looks for the track closest to the current head position?

• A. LOOK
• B. SSTF
• C. FCFS
• D. SCAN

Hint:

SSTF minimizes the seek time by choosing the closest track to the current position of the disk head.

Answer 1

The Correct Option is B

Step 1: Definition of SSTF.
The SSTF (Shortest Seek Time First) disk scheduling algorithm selects the track that is closest to the current head position, thus minimizing the seek time for each disk access.

Step 2: Analysis of other options.
- (1) LOOK: This algorithm moves the head towards the end of the disk and reverses direction when the end is reached, searching for the requested track.
- (3) FCFS: First Come First Serve simply services requests in the order they arrive, without considering the track location.
- (4) SCAN: Similar to LOOK, it moves the head in one direction until it reaches the end, then reverses direction.

Step 3: Conclusion.
The correct answer is **SSTF**, which looks for the track closest to the current head position.