Bachelors Level/Second Year/Fourth Semester/Science csit/fourth semester/operating systems/syllabus wise questions

B.Sc Computer Science and Information Technology

Institute of Science and Technology, TU

Operating Systems (CSC264)

Year Asked: 2076, syllabus wise question

Device Management
1.
When programmed IO is suitable than other IO handling techniques? Explain the process of IO handling using DMA. [5]
2.
What is problem associated with semaphores? Explain the concept of monitors in brief. [5]
File Management
1.
What is the main objective of disk scheduling algorithms? Why SSTF is not practically feasible? Assume that we have disk with 100 tracks and currently head is at track number 35. What will be the seek time for the algorithms SCAN and LOOK for processing IO requests queue: 52, 67, 21, 11, 43, 85, 18, 75, 92, 8? [10]
2.
How can you manage free disk space? Explain the linked list approach of managing free disk space with example. [5]
Linux Case Study
1.
Write short notes on: a. Linux File System b. Resource Allocation Graph [5]
Memory Management
1.
How Second Chance page replacement algorithm differs from FIFO page replacement policy? Discuss the concept of Belady’s anomaly with suitable example. [10]
2.
Why program relocation and protection is important? Explain the technique of achieving program relocation and protection. [5]
Operating System Overview
1.
What are two modes of OS? Discuss different OS structures briefly. [5]
2.
Differentiate between multi programming and Monoprogramming. What will be the CPU utilization with 6 processes with 60% IO waiting time are in memory? [5]
Process Deadlocks
1.
Differentiate between deadlock and starvation? Discuss the process of detecting deadlocks when there are multiple resources of each type. [5]
Process Management
1.
Defined interactive system goals? List various interactive scheduling algorithms. Consider following process data and compute average waiting time and average turnaround time for RR(quantum 10) and priority scheduling algorithms.

$\begin{array}{|c|c|c|c|} \hline \text{PID} & \text{Burst Time} & \text{Arrival Time} & \text{Priority} \\ \hline A & 16 & 0 & 1 \\ B & 37 & 12 & 2 \\ C & 25 & 7 & 3 \\ \hline \end{array}$
[10]
2.
When threads are better than processes? Explain the concept of user level threads in detail. [5]