Unit 3 CPU Scheduling
Long Answer Question with Answer
Q1. What is CPU scheduling? Give the criteria for scheduling?
OR
Discuss the performance criteria for CPU scheduling?
AKTU 2015-16
Q2. What is the difference between preemptive and non pre-emptive scheduling? State, why strict non pre-emptive scheduling is unlike to be used in compute center? Explain the operation of multi-level scheduling?
Q3. List out the various states of process?
OR
Draw the process state diagram and describe the various process states?
OR
what are the various process states? depict process state diagram. What do you understand by context switching and various process involve in it?
OR
Draw and explain the process state transition diagram?
AKTU 2011-12
Q4.What is process control block? Also list out the information it contains?
OR
What is process control block? Explain all its component?
Q5. Differentiate between long term, short term and mid term schedulers?
Q6. Discuss First Come First Serve scheduling algorithm? Give its advantage and disadvantage?
Q7. Discuss Shortest job First (SJF) scheduling algorithm? also write its advantages and disadvantages?
Q8. What is CPU scheduling? Discuss the multilevel feedback queue scheduling?
Q9. Explain the following scheduling algorithm?
- Multilevel feedback queue scheduling
- Multiprocessor scheduling
AKTU 2014-15
Q10. What is thread? differentiate between User Level Thread and kernel level thread? What is thread cancellation?
OR
what is a thread? How thread is different from a process? What resource are used when a thread is created?
Q11. consider a variant of Round Robin scheduling algorithm where the entries in the ready queue are pointers to the processes? what would be the effect of putting two pointers to the same process in the ready queue? What would be advantage and disadvantage of this scheme?
AKTU 2012-13
Q12. Consider the set of the processes given in the table and the following scheduling algorithm:
- Round Robin (Quantum= 1)
- Round Robin (Quantum= 2)
- Shortest Remaining Job First
|
P id |
Arrival |
Execution |
|
1 |
0 |
4 |
|
2 |
2 |
7 |
|
3 |
3 |
3 |
|
4 |
3.5 |
3 |
|
5 |
4 |
5 |
if there is tie within the processes the tie is broken in the favour of the oldest process. Draw the Gantt Chart and find the average waiting time, Response time and turnaround time for the algorithms? comment on your result? Which one is better and why?
AKTU 2013-14
Q13. Consider the processes, CPU burst time and arrival time given below
|
P id |
CPU burst time |
Arrival Time |
|
1 |
8 |
0 |
|
2 |
4 |
1 |
|
3 |
5 |
2 |
|
4 |
5 |
3 |
Draw the Gantt chart and calculate the following by using SRTF CPU scheduling algorithm
1. Average waiting Time
2. Average turn around time
Q14. list various performance criteria for scheduling algorithms. Five processes A,B,C,D,E require burst time of 3,5,2,5,5 units respectively. Their arrival times in the system is 0, 1, 3, 9 and 12 respectively. Draw Gantt chart and compute the average turn around time and average waiting time of these processes for the Shortest Job first (SJF) and Shortest Remaining Time first (SRTF) scheduling algorithm?
Q15. What is deadlock? What is the necessary condition for deadlock?
OR
What are the necessary condition to hold a deadlock in a system?
OR
What is dead lock? Discuss the necessary condition for deadlock with example?
AKTU 2013-14, AKTU 2016-17
Q16. How deadlock are prevented?
OR
Define and explain the deadlock prevention?
OR
what the approaches that can be used for prevention of deadlock?
AKTU 2013-14
Q17. What is deadlock avoidance? Define all states of the system?
Q18. Describe resource allocation graph?
Q19. Define deadlock detection? Write an algorithm for deadlock detection?
Q20. What are the two ways in which deadlock can be detected?
Q21. A safe state is not a deadlock state but a deadlock state is an unsafe state”. Explain Discuss the different methods for handling dead locks?
Q22. Define deadlock. List four necessary condition for occurrence of deadlock? A system contains 6 units of resources and n processes that use the resource? What is the maximum value of n for which the system will be deadlock free if the maximum requirement of each process is 3?
AKTU 2012-13
Q23. Write an algorithm for detection of deadlock in a system having several instance of multiple resource types?
AKTU 2012-13
Q24. Write the Banker’s algorithm and how it can be used to avoid can be used to avoid deadlock?
OR
Describe Banker’s algorithm for safe allocation?
OR
Write and explain Banker’s algorithm for avoidance of dead lock?
AKTU 2016-17, AKTU 2011-12
Q25. Describe Banker’s algorithm for deadlock avoidance. Consider a system with three process and three resource? The snap shot of a system at time t0 is given below?
|
Proid |
Allocation |
Max |
Available |
||||||
|
|
A |
B |
C |
A |
B |
C |
A |
B |
C |
|
P0 |
2 |
2 |
3 |
3 |
6 |
8 |
7 |
7 |
10 |
|
P1 |
2 |
0 |
3 |
4 |
3 |
3 |
|
|
|
|
P2 |
1 |
2 |
4 |
3 |
4 |
4 |
|
|
|
1. is the current allocation in safe state
2. would the following requests be granted in the current state:
Process p2 requests (1,0,0)
Process p1 requests (1,0,0)
AKTU 2014-15
Q26. Consider the following snapshot of the system
|
Proid |
Allocation |
Max |
Available |
||||||||||
|
|
A |
B |
C |
D |
A |
B |
C |
D |
A |
B |
C |
D |
|
|
P0 |
0 |
0 |
1 |
2 |
0 |
0 |
1 |
2 |
1 |
5 |
2 |
0 |
|
|
P1 |
1 |
0 |
0 |
0 |
1 |
7 |
5 |
0 |
|
|
|
|
|
|
P2 |
1 |
3 |
5 |
4 |
2 |
3 |
5 |
6 |
|
|
|
|
|
|
P3 |
0 |
6 |
3 |
2 |
0 |
6 |
5 |
2 |
|
|
|
|
|
|
P4 |
0 |
0 |
1 |
4 |
0 |
6 |
5 |
6 |
|
|
|
|
|
answer the following question using banker’s algorithm
1. What is the content of the matrix need?
2. Is the system in a safe state? if yes then find the safe sequence?
3.if a request from process p1 arrived for (0,4,2,0) can request be granted immediately?
Q27. Differentiate between deadlock and starvation?
AKTU 2011-12
Q28.Define the different states of a process with diagram? Explain the need of process suspension?
AKTU 2013-14