Explain the need for the Process Control Block (PCB) fields. (Unit 3)

Given the following table:

Answer the following questions:
i) Give the scheduling sequence of these processes according to FCFS, Round Robin (Time Quantum=3), pre-emptive SJF. (a larger no. implies a higher priority).
ii) Compute the turnaround time for each process for each of scheduling algorithms in part (i).
iii) Compute the waiting time for each process for each of scheduling algorithms in part (i). (Unit 3)

How multilevel feedback queue scheduling differs from multilevel queue scheduling. (Unit 3)

What is Resource Allocation Graph? Explain the occurrence and avoidance of deadlock graphically among 3 processes and 3 resources. (Unit 4)

The following is the sequence of page requests: 1, 2, 3, 5, 4, 1, 2, 5, 3, 2, 4, 3. Assume that there are three frames. Now, how many page faults will occur if an Optimal Page Replacement algorithm is used to replace pages? (Unit 3)

Write short notes on the following: (Any two)

a) Thrashing (Unit 3)

b) LRU algorithm (Unit 3)

c) Process Control Block (Unit 3)

d) Contiguous and Linked Disk Allocation Method (Unit 2)

e) Optimal Page Replacement algorithm (Unit 3)

f) Interrupts (Unit 4)
Multilevel Feedback Queue Scheduling (Unit 3)

Define the term "Directory". Explain any two schemes of logical directory structures. (Unit 2)

When do page-faults occur? Describe the action taken by the O.S when page-fault occurs. (Unit 3)