B.Tech., IV Semester
Examination, November 2023
Grading System (GS)
Max Marks: 70 | Time: 3 Hours
Note:
i) Answer any five questions.
ii) All questions carry equal marks.
a) List and explain the various features of operating system. (Unit 1)
b) Describe the evolution of operating system in detail. (Unit 1)
a) Discuss the various services provided by operating system. (Unit 1)
b) Write and explain the Banker's algorithm for dead lock avoidance. (Unit 2)
a) Consider the following set of process, with the length of the CPU burst given in milliseconds.
| Process | Burst Time | Priority |
|---|---|---|
| $P_{1}$ | 10 | 3 |
| $P_{2}$ | 1 | 1 |
| $P_{3}$ | 2 | 3 |
| $P_{4}$ | 1 | 4 |
| $P_{5}$ | 5 | 2 |
The processes are assumed to have arrived in the order $P_{1},$ $P_{2},$ $P_{3}$, $P_{4},$ $P_{5}$ all at time 0. Calculate the turnaround time of each process by applying priority scheduling algorithm. (Unit 2)
b) Explain the Peterson solution for critical section problem. (Unit 2)
a) Discuss the advantage of segmentation over paging. (Unit 3)
b) Explain in brief the need of demand paging. (Unit 3)
a) Define Belady's anomaly. Why does Belady's anomaly happen explain with an example? (Unit 3)
b) Suppose the head of a moving head disk with 200 tracks, numbered 0 to 199, is currently serving a request at track 143 and has just finished a request at track 125. If the queue of requests is kept in FIFO order: 86, 147, 91, 177, 94, 150, 102, 175, and 130. What is the total head movement to satisfy these requests for the FCFS disk scheduling algorithms? (Unit 4)
Explain the following with relevant diagrams:
a) Two level directory structure (Unit 4)
b) Acyclic-graph directory structure (Unit 4)
a) Discuss in brief the logical structure of I/O function. (Unit 5)
b) Explain the interrupt driven I/O techniques. (Unit 5)
Discuss in brief any of the following:
a) User level and kernel level threads (Unit 2)
b) Virtual memory (Unit 3)
c) Tape organization (Unit 4)
d) I/O Buffering (Unit 5)
