Assignment No. 03 Semester: Fall 2014 CS604 –Operating System Total Marks: 15 Due Date: 16/2/2015

[+ Aqib]

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Assignment
Question 1:   (5 Marks)   Consider the following snapshot of a system:     Allocation Max Available   A B C D A B C D A B C D P0 1 1 1 2 3 4 2 2 1 2 3 4 P1 1 0 2 2 1 3 4 14         P2 1 4 5 6 2 7 5 8         P3 2 5 4 2 3 5 7 9         P4 1 5 2 7 1 6 3 9           Need A B C D                                           Answer the following questions using the banker’s algorithm:   (a)   What is the content of the matrix Need?                                             5     (b)   Is the system in a safe state? If yes identify the safe sequence. Show the step by step execution by updating the data structure if necessary.                                                            10     NOTE:Do not put any query on MDB about this assignment, if you have any query then [e-mail].
Deadline: Your assignment must be uploaded/submitted on or before

[saleem Kalro]

safe sequence is <P4, P0, P1, P2, P3>

this is correct answer

but i can be achieved in 3 or four steps

[sadima]

This is the corrected solution plz change it before submit and pray for me.

[nazish noor]

thnk  u 

[Maham Ali]

Thanks ......

[lll.NaYaB.lll(Mcs)]

thanxxxxxx

[shagufta parveen]

thanx GODbless u

[NADEEM Ch]

thanks

[zunaira malik]

thanku

[syed qaisar javaid]

My Solution:

Need
A	B	C	D
2	3	1	0
0	3	2	12
1	3	0	2
1	0	3	7
0	1	1	2

[syed qaisar javaid]

	Need				Allocation				Available
Process	A	B	C	D	A	B	C	D	A	B	C	D
P0	2	3	1	0	1	1	1	2	1	2	3	4
P1	0	3	2	12	1	0	2	2	2	7	5	11
P2	1	3	0	2	1	4	5	6	3	8	6	13
P3	1	0	3	7	2	5	4	2	4	8	8	15
P4	0	1	1	2	1	5	2	7	5	12	13	21

[syed qaisar javaid]

Enjoy dear students: Best of luck

[syed qaisar javaid]

Safe sequence

 < P4, P0, P1, P2, P3 >