UGC NET · PAPER 2
UGC NET Paper 2 Computer Science – Unit 5: System Software and Operating System PYQ (December 2024)
Q27. Consider the following disk-scheduling movement and identify the algorithm it represents. Request queue: 84, 125, 11, 36, 170, 20, 172, 45 (cylinders 0–199). The head starts at cylinder 28 and services 36 → 45 → 84 → 125 → 170 → 172 moving towards higher cylinders, then jumps directly back to 11 (without going to 199 or 0) and services 11 → 20.
- SSTF
- SCAN
- C-SCAN
- C-LOOK
Q41. Match List I with List II
| List I | List II |
|---|---|
| A. RAID level 1 | I. Bit-interleaved parity organization |
| B. RAID level 2 | II. Disk mirroring |
| C. RAID level 3 | III. Block-interleaved parity organization |
| D. RAID level 4 | IV. ECC organization |
- A-II, B-I, C-IV, D-III
- A-II, B-IV, C-I, D-III
- A-III, B-IV, C-I, D-II
- A-IV, B-III, C-II, D-I
Q47. If the virtual memory size is 32 MB and the physical memory size is 4 MB with a page size of 2 KB, calculate the number of frames available in physical memory.
- 1024
- 2048
- 3072
- 4096
Q76. Which of the following does NOT interrupt a running process?
- Device
- Timer
- Scheduler
- Power Failure
Q77. Given the following processes with their burst times and priorities (lower number indicates higher priority), all arriving at time 0, what is the average waiting time using the (non-preemptive) priority scheduling algorithm?
| Process | Burst Time | Priority |
|---|---|---|
| P1 | 10 | 3 |
| P2 | 1 | 1 |
| P3 | 2 | 4 |
| P4 | 1 | 5 |
| P5 | 5 | 2 |
- 9.2
- 6.8
- 7.6
- 8.2
Directions (Q96–100): Consider the following set of processes with arrival time and CPU burst time given in milliseconds (ms):
| Process | Arrival Time | Burst Time |
|---|---|---|
| P1 | 0 | 5 |
| P2 | 2 | 3 |
| P3 | 2 | 2 |
| P4 | 5 | 3 |
| P5 | 6 | 1 |
Q96. Calculate the average response time for these processes with the non-preemptive priority scheduling algorithm. Priorities are as follows; consider that all the processes arrive at time 0 (low numbers represent high priority).
| Process | Burst Time | Priority |
|---|---|---|
| P1 | 5 | 3 |
| P2 | 3 | 1 |
| P3 | 2 | 5 |
| P4 | 3 | 4 |
| P5 | 1 | 2 |
- 5.6 ms
- 5.2 ms
- 4.7 ms
- 3.8 ms
Q97. Find the average weighted turnaround time for these processes using the Highest Response Ratio Next (HRN) algorithm.
- 3.2 ms
- 2.834 ms
- 1.632 ms
- 6.721 ms
Q98. What is the average turnaround time for these processes with the First Come First Serve (FCFS) scheduling algorithm?
- 5.3 ms
- 6.4 ms
- 7.0 ms
- 8.2 ms
Q99. What is the average waiting time for these processes with non-preemptive Shortest Job First (SJF) scheduling?
- 3.0 ms
- 2.1 ms
- 4.6 ms
- 3.2 ms
Q100. When we apply the Shortest Job First (SJF) scheduling algorithm, process P2 faces partial starvation and waits a longer time to execute. Which one of the following algorithms addresses this problem?
- Round Robin
- Priority
- Highest Response Ratio Next
- Least Completed Next