SRM University 2007 B.Tech Computer Science and Engineering BANK : OPERATING SYSTEMS - Question Paper

19. discuss how semaphores may be inspected/manipulated?
20. What do you mean by weak and strong semaphore?
21. State producer/consumer issue.
22. What is a monitor?
23. What conditions are generally associated with learners and authors problem?
24. What are the 3 conditions that must be current for deadlock to be possible?
25. What are the 4 conditions that create deadlock?
26. Give example for reusable and consumable resource.
27. How can the hold and wait condition be prevented?
28. List 2 ways in which no-preemption condition can be prevented.
29. How the circular wait condition be prevented?
30. What is the difference among the dead lock avoidance, prevention and detection?
31. What is safe and unsafe state?
32. Define turnaround time, waiting time, and response time.
33. What do you mean by scheduling?
34. What are the kinds of scheduling? provide example.
35. Write the difference ranging from preemptive and non preemptive scheduling?
36. Briefly define the 3 kinds of processor scheduling.
37. Briefly discuss FCFS scheduling.
38. Briefly discuss Round robin scheduling.
39. Briefly discuss SPN scheduling.
40. Briefly discuss SRTF scheduling.
41. Briefly discuss HRRN scheduling.
42. Briefly discuss Feedback scheduling.


PART B

1. Consider the subsequent set of processes with the length of CPU burst time provided in ms.
Process Burst time Priority

P1 8 3
P2 3 1
P3 4 4
P4 2 2
P5 6 5

Processes are presumed to have arrived in the order P1, P2, P3, P4 & P5 and all at time 0.

i. Draw four Gantt charts illustrating the execution of these processes using FCFS,SJF non-preemptive, RR(quantum =2) scheduling.
ii. What is turnaround time, waiting time, avg. waiting time of every process for every of the scheduling?

2. a)Explain Dekkar’s algorithm for solving mutual exclusion issue.
b)Consider a system with a total of 150 units of memory, allocated to 3 processes as shown:

Process Max Hold
1 70 45
2 60 40
3 60 15

Apply banker’s algorithm to determine it would be safe to grant every of the subsequent requests.If yes, indicate a sequence of terminations that could be guaranteed possible.If no, show the reduction of the resulting allocation table.
i.A 4th process arrives with maximum memory need of 60 and initial need of 25 units.
ii. A 4th process arrives with maximum memory need of 60 and initial need of 35 units.

Earning:   Approval pending.