Operating System BS IT term 5th Past Paper 2017 UOS
University of Sargodha
BS 5th Term Examination 2017
Subject: I.T
Paper: Operating System (CMP: 3621)
Time Allowed: 2:30 Hours
Maximum Marks: 80
Objective Part Compulsory
Q.NO.1: – Answer the following questions in 2-3 lines having 2 marks each
[12×2=24]
- What is multiprogramming?
- What are the four conditions of deadlock?
- Explain long term scheduler.
- Under what circumstances do page faults occur?
- What is Memory-Management Unit?
- Different types of Real-Time Scheduling?
- What is Dispatcher?
- What is virtual memory?
- What is a deadlock?
- What are types of threads?
- What is a ready queue?
- What is PCB?
Subjective Part
Note: Attempt any three Questions. All carry equal marks
[12×3=36]
Q.No.2
a) Briefly explain the operating system services.
b) Describe the Simple Batch System and Time sharing system.
Q.No.3
a) Define System Calls. What are the main types of System calls?
b) What are differences between user-level threads and kernel-level threads?
Q.No.4
Suppose that a disk drive has 200 cylinders, numbered from 0 to 199. The disk head is initially at cylinder 53. The queue of pending requests, in FIFO order, is: 98, 183, 37, 122, 14, 124, 65, 67
Starting from the current head position, what is the total distance (in cylinders) that the disk arm moves to satisfy all the pending requests for each of the following disk-scheduling algorithms?
a) FCFS
b) SSTF
c) Scan
d) C-Scan
Q.No.5
a) What is semaphore? How semaphore works for synchronizations of the processes?
b) Briefly explain the segmentation.
Q.No.6
Consider the following set of processes, with the length of the CPU burst given in milliseconds: