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D192037 Pages:3

Process Arrival time Burst time
Pl 0 8
P2 2 4
P3 + 9
P4 5 5
Consider the following snapshot of a system
Process Allocation Max Available

ABCD ABCD ABCD
PO 001 2 0012 1520
Pl 100 0 1750
P2 135 4 2356
P3 0632 0652
P4 0014 0656

Answer the following questions using Bankers algorithm
a. What is the content of "Need" matrix?
b. Is the system in a safe state? Justify your answer.
௦. If a request from 01 arrive (04 2 0), can the request be granted immediately
PARTE
Answer any four questions. Each carries 10 marks.
Explain the concept of paging.
With the help of a diagram, explain logical address to physical address translation
in paging. Illustrate with an example.
Describe contiguous memory allocation.

Given six memory partitions of 300 KB, 600 KB, 350 KB, 200 KB, 750 KB, and
125 KB (in order), how would the first-fit, best-fit, and worst-fit algorithms place
processes of size 115 KB, 500 KB, 358 KB, 200 KB, and 375 KB (in order)?

Rank the algorithms in terms of how efficiently they use memory.

Explain Optimal page replacement and LRU algorithms for page replacement

Find the number of page faults for the following page reference string with 3 page
frames for Optimal page replacement and LRU algorithms.

2342137543

Explain "Elevator" algorithm for disk scheduling with example.

Total cylinders in a disk is 5000 [0-4999]. Header is at position 143; previous
request is for 125, request queue is 86,1470, 913, 1774, 948, 1509, 1022, 1780, 130

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