Consider the following process and resource requirement of each process. Type…
2013
Consider the following process and resource requirement of each process.
Type 1 Type 2
Process Used Max Used Max
P1 1 2 1 3
P2 1 3 1 2
P3 2 4 1 4 Predict the state of this system, assuming that there are a total of 5 instances of resource type 1 and 4 instances of resource type 2.
- A.
Can go to safe or unsafe state based on sequence
- B.
Safe state
- C.
Unsafe state
- D.
Deadlock state
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Correct answer: C
First, calculate the available resources for each type by subtracting total used from total instances. For Type 1: Total is 5, Used is 4 (1+1+2), so Available = 1. For Type 2: Total is 4, Used is 3 (1+1+1), so Available = 1. The Available Vector is [1, 1].
Next, calculate the remaining need for each process using (Max - Used). P1 Need = [2-1, 3-1] = [1, 2]. P2 Need = [3-1, 2-1] = [2, 1]. P3 Need = [4-2, 4-1] = [2, 3].
Finally, check if any process can be satisfied with the available resources [1, 1]. P1 needs 2 of Type 2 (Available is 1). P2 needs 2 of Type 1 (Available is 1). P3 needs more than available. Since no process can proceed, the system is in an unsafe state.