UGC-NET | UGC NET CS 2014 Dec – III | Question 52
An operating system has 13 tape drives. There are three processes P1, P2 & P3. Maximum requirement of P1 is 11 tape drives, P2 is 5 tape drives and P3 is 8 tape drives. Currently, P1 is allocated 6 tape drives, P2 is allocated 3 tape drives and P3 is allocated 2 tape drives. Which of the following sequences represent a safe state ?
(A) P2 P1 P3
(B) P2 P3 P1
(C) P1 P2 P3
(D) P1 P3 P2
Answer: (A)
Explanation: Maximum need for the process P1 P2 P3 is 11, 5, 8 and current allocation is 6, 3, 2 respectively. Total 13 tape drive were present out of which 11 are allocated and left with 2 drives.
Now P1 needs 5; P2 needs 2; P3 needs 6 tape Only P2’s need can be fulfilled. Now after P2 execute 5 tapes are free which can fulfill P1’s demand after that p1 will execute.
Execution order will be P2 P1 P3.
So, option (A) is correct.
Quiz of this Question
Last Updated :
04 Jul, 2018
Like Article
Save Article
Share your thoughts in the comments
Please Login to comment...