Dead lock recovery

Question

Maximum        allocation           available

      A B C D         A B C D           A B C D

p0  6 0 1 2          4 0 0 1             3 2 1 1

p1  2 7 5 0          1 1 0 0

p2  2 3 5 6          1 2 5 4

p3  1 6 5 3           0 6 3 3

p4  1 6 5 6           0 2 1 2

 

 

What is the total number of instances of each resource type?Find a safe sequence of given system

Answer 1

From given data ..

Max Requirement	Allocated	Need Matrix
6   0    1     2	4   0    0   1	2     0    1     1
2   7    5     0	1    1   0   0	1     6     5    0
2    3    5    6	1    2   5   4	1     1      0   2
1    6     5   3	0    6    3   3	1      0     2    0
1     6    5   6	0     2    1   2	1      4     4     4

Now avaliable are 3 2 1 1 ..so we can satisfy only Process P0 ..so free resources are 7 2 1 2 

Now execute P2 so we get 8 4 6 6 resources .

Now  P4 we get 8 6 7 8 

then P3 we get  8 12 10 11 

Now P1 we get  9 13 10 11