Tribhuvan University
Bachelor of Computer Application
Semester 4 · TU Board 2024
Course Title: Operating System (CACS251)
Full Marks: 60Pass Marks: 24Time: 3 hours
Candidates are required to answer the question in their own words as far as possible.
Group A
Group B
Attempt any SIX question.(6 × 5 = 30)
- 2.5
Define kernel. Explain different types of kernel in operating system.
Answer comingAlso asked in 2023, 2020
- 3.5
What is PCB? What are different information that are included in a PCB?
- 4.5
How paging can be used for memory management? Also differentiate it with segmentation.
Answer comingAlso asked in 2026
- 5.5
What are page faults and thrashing? Explain demand paging with protection bit.
- 6.5
How deadlock can be prevented? Explain in detail.
- 7.5
Explain different file access methods in detail.
- 8.5
What is distributed system? Explain the role of clock synchronization in distributed system.
Answer comingAlso asked in 2026
Group C
Attempt any TWO questions(2 × 10 = 20)
- 9.10
What is critical section problem? How semaphores can be used to solve critical section problem Also explain producer consumer problem with its solution using Mutex.
- 10.10
What is Belady's Anomaly in page replacement Algorithm? Explain with example. Consider the following page reference string: 7, 2, 3, 1, 2, 5, 3, 4, 6, 7, 7, 1, 0, 5, 4, 6, 2, 3, 0, 1 How many page facts will occur if the program has four page frames available to it and usesthe following page replacement algorithm? a) FIFO replacement b) LRU replacement c) Optimal replacement
- 11.10
What is use of DMA controller? Consider the following process and answer the following questions.ProcessAllocationMaxAvailable[A,B,C,D][A,B,C,D][A,B,C,D]P00 0 1 10 0 1 21 5 2 0P11 0 0 01 7 5 0P21 3 5 42 3 5 6P30 6 3 20 6 5 2P40 0 1 40 6 5 6a) What is the content of need matrix? b) Is the system in safe state? c) If P2 request (3 4 0 2), can the request be granted Immediately.
Answer comingAlso asked in 2022
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