1. Disk scheduling is concerned with:
A) Memory allocation
B) CPU scheduling
C) Order of servicing disk I/O requests
D) File permissions
C) Order of servicing disk I/O requests
2. The main objective of disk scheduling algorithms is to:
A) Maximize disk space
B) Minimize seek time
C) Increase memory utilization
D) Avoid deadlock
B) Minimize seek time
3. Which disk scheduling algorithm services requests in arrival order?
A) SSTF
B) SCAN
C) FCFS
D) LOOK
C) FCFS
4. Which disk scheduling algorithm may cause starvation?
A) FCFS
B) SSTF
C) SCAN
D) C-SCAN
B) SSTF
5. SSTF stands for:
A) Shortest Seek Time First
B) Smallest Sector Transfer First
C) Shortest Service Time First
D) Sequential Seek Time First
A) Shortest Seek Time First
6. Which algorithm selects the request closest to the current head position?
A) FCFS
B) SCAN
C) SSTF
D) LOOK
C) SSTF
7. The SCAN disk scheduling algorithm is also known as:
A) Elevator algorithm
B) Circular scan
C) Shortest job next
D) FIFO scan
A) Elevator algorithm
8. In SCAN scheduling, the disk head:
A) Moves in one direction only
B) Services requests only at ends
C) Moves back and forth across disk
D) Randomly accesses tracks
C) Moves back and forth across disk
9. Which disk scheduling algorithm provides more uniform wait time?
A) SSTF
B) FCFS
C) SCAN
D) C-SCAN
D) C-SCAN
10. C-SCAN differs from SCAN because:
A) Head reverses direction
B) Head services only one direction
C) Requests are ignored
D) Disk is accessed randomly
B) Head services only one direction
11. LOOK disk scheduling differs from SCAN because:
A) It skips end tracks with no requests
B) It moves only in one direction
C) It ignores seek time
D) It causes starvation
A) It skips end tracks with no requests
12. C-LOOK algorithm:
A) Always goes to disk end
B) Services requests circularly without reaching disk end
C) Is same as SCAN
D) Uses FCFS order
B) Services requests circularly without reaching disk end
13. Which algorithm has the least implementation complexity?
A) SSTF
B) SCAN
C) FCFS
D) LOOK
C) FCFS
14. Disk scheduling algorithms mainly reduce:
A) Rotational latency
B) Transfer time
C) Seek time
D) Access permission
C) Seek time
15. Starvation in disk scheduling means:
A) Disk failure
B) Request never serviced
C) Disk overflow
D) Seek time is zero
B) Request never serviced
16. Which algorithm reduces starvation compared to SSTF?
A) FCFS
B) SCAN
C) FIFO
D) Random
B) SCAN
17. Which disk scheduling algorithm treats requests uniformly?
A) SSTF
B) FCFS
C) C-SCAN
D) LOOK
C) C-SCAN
18. Disk scheduling is done by:
A) Application program
B) Compiler
C) Operating system
D) Disk controller only
C) Operating system
19. Which factor does NOT affect disk performance?
A) Seek time
B) Rotational latency
C) Transfer rate
D) CPU clock speed
D) CPU clock speed
20. Disk scheduling algorithms are most useful when:
A) Disk is idle
B) Disk load is high
C) Only one request exists
D) CPU utilization is low
B) Disk load is high
21. Which algorithm gives better throughput under heavy load?
A) FCFS
B) SSTF
C) SCAN
D) Random
C) SCAN
22. Which scheduling algorithm is fair but inefficient?
A) SSTF
B) FCFS
C) SCAN
D) C-SCAN
B) FCFS
23. Which disk scheduling algorithm is best for real-time systems?
A) FCFS
B) SSTF
C) SCAN
D) Depends on constraints
D) Depends on constraints
24. Which disk scheduling algorithm does NOT cause starvation?
A) SSTF
B) FCFS
C) SCAN
D) Both B and C
D) Both B and C
25. Disk scheduling improves system performance by:
A) Increasing disk size
B) Reducing seek movements
C) Increasing page size
D) Reducing memory usage
B) Reducing seek movements