Mumbai University question question paper 4th Sem Computer science
(1) QuestionNo.1 is compulsory.
(2) Attempt any four questions out of remaining six questions.
1. (a) Explain features of Modern operating system.
(b) What are requirements of mutual exclusion? Explain Peterson’s algorithm
for mutual exclusion.
(c) Explain effect of page type (too small or too large) on performance.
(d) Differentiate between Monolithic Kernel and Micro Kernel.
2. (a) What is PCB? Explain importance of PCB in multiprocesor environment. 10
(b) What is deadlock? Explain two approaches for deadlock avoidance. 10
33! (a) Explain ULTs and KLTs in detail. 10
.(t;» Considera systemwithtotal of 150unitsof memoryallocatedto three processes 10
Apply Banker’s algorithm to determine whether it would be safe to grant each
of following request. If yes, indicate sequence of termination that could be
possible. If no show reduction of resulting allocation table.
(i) A fourth process arrives with max need of 60 and initial need of 25
(ii) A fourth process arrives with max need of 60 and initial need of 35
(a) What are characteristics of real time operating ~ystem and explain in detail 10
real time scheduling.
(b) Explain types of processor scheduling. 10
5. (a) State various page replacement policies and calculate hit for (LRU, FIFO, OPT) 10
for page frame of following sequence where page frame size is three:
0, 1, 2, 1, 4, 2, 3, 7, 2, 1, 3, 5, 1, 2, 5.
(b) What are requirements of memory management? Explain segmentation with 10
6. (a) What types of files in Unix? Explain Unix file management.
(b) Explain file allocation in detail.
7. Write short notes on the following:
(a) Mobile OS
(c) 1/0 buffering
(d) System calls.