Operating System BS 2 Semester/Term UOSindh — University of Sindh 2023

Institute of Mathematics & Computer Science

University of Sindh, Jamshoro

BS (CS) part - III 2nd Semester Examination (Morning and Evening) Regular

Operating System

December 7, 2023, Marks 50 Time: 2 hours

Note: Attempt any four questions and question no 7 is compulsory.

Q.No.1 What is the distinction between segmentation and segmentation with paging, discuss in detail their

memory management issues?

Q.No.2 Define the history of operating system in a chronological order, also elaborate the batch processing and

timesharing and their issues.

Q.No.3

(a) discuss the interrupt execution cycle and also role of an interrupt in the process execution cycle.

(b) Compare different techniques for CPU operations. And how CPU protection is implemented.

Q.No.4

(a) What does it mean to say a process is heavy weight whereas a thread is a light weight process?

(b) Discuss any two examples for each of the two scenarios: (1) single processor system is better than

Multiprocessor system. And (2) multiprocessor system is better than single processor system

Q.No.5 What is context-switching? Also, discuss the role of the process control block (PCB) in context-switching

between processes performed by the operating system

Q.No.6 Define the following terms

(1) Aging (2) Thrashing (3) compaction (4) medium term scheduler

Q.No.7

(a) Process CPU Burst Arrival Time

P1 7 0

P2 4 1

P3 2 1.5

P4 1 2

Define and determine the waiting time and turnaround time of each of the above processes with SJF

and round ribbon (time quantum 2 sec)

Q.No.7

(b) What are the conditions are checked by long term scheduler to select process for memory allocation.

***** FIRST DESERVE THEN DESIRE *****