Questions
Syllabus
Qns. By Syllabus

Semester

Subject

Year

Tribhuwan University

Institute of Science and Technology

2079

Bachelor Level / Second Year / Third Semester / Science

Bachelors in Information Technology (BIT204)

(Operating Systems)

Full Marks: 60

Pass Marks: 24

Time: 3 Hours

Candidates are required to give their answers in their own words as for as practicable.

The figures in the margin indicate full marks.

Section A

Long Answers Questions

Attempt any TWO questions.
[2*10=20]
1.
What are the different types of operating system? Differentiate between Real time and Batch OS. [10]
2.
What is kernel? Explain the process of system call with suitable diagram. [10]
3.
What is Resource Allocation Graph (RAG)? What are the necessary conditions for deadlock? Explain. Determine if the system is safe from deadlock or not using Banker's Algorithm for given condition.
Need MatrixProcessABCP11164P2341P3823P4324P5523\begin{array}{|c|c|c|c|}\hline \text{Need Matrix} & & & \\ \hline \text{Process} & A & B & C \\ \hline P1 & 11 & 6 & 4 \\ P2 & 3 & 4 & 1 \\ P3 & 8 & 2 & 3 \\ P4 & 3 & 2 & 4 \\ P5 & 5 & 2 & 3 \\ \hline \end{array}
Allocation MatrixProcessABCP1311P2310P3411P4101P5201\begin{array}{|c|c|c|c|}\hline \text{Allocation Matrix} & & & \\ \hline \text{Process} & A & B & C \\ \hline P1 & 3 & 1 & 1 \\ P2 & 3 & 1 & 0 \\ P3 & 4 & 1 & 1 \\ P4 & 1 & 0 & 1 \\ P5 & 2 & 0 & 1 \\ \hline \end{array}
MAX Resource MatrixABC17810\begin{array}{|c|c|c|}\hline \text{MAX Resource Matrix} & & \\ \hline A & B & C \\ \hline 17 & 8 & 10 \\ \hline \end{array}
[10]
Section B

Short Answers Questions

Attempt any Eight questions.
[8*5=40]
4.
What is an OS? Explain 3-state model of process with neat and clean diagram. [5]
5.
What is race condition? Explain critical problem solution using lock variable. [5]
6.
What is memory compaction? Explain best fit memory allocation with suitable example. [5]
7.
What is RAID? Explain Level-2 and Level-3 RAID. [5]
8.
How threads differ from processes? Explain user level thread and kernel level thread. [5]
9.
Consider the following page reference string: 3,2,1,3,4,2,8,9,7,4,2,9,8,3. Calculate the total number of page faults for Optimal and LRU page replacement algorithms using a 4 page frame. [5]
10.
What is TLB? Explain the importance of TLB in conversion of logical address to physical address. [5]
11.
Consider 500 GB hard drive with 5 KB block size. Calculate the size of the file allocation table if entry for each block needs 4 bytes. [5]
12.
Explain the working mechanism of DMA. [5]