Consider a system with 3 processes that share 4 instances of the same resource type

Q. Consider a system with 3 processes that share 4 instances of the same resource type. Each process can request a maximum of 𝐾 instances. Resource instances can be requested and released only one at a time. The largest value of 𝐾 that will always avoid deadlock is .

Ans: 2

Sol:

Given,
Number of processes (P) = 3
Number of resources (R) = 4

Since deadlock-free condition is:R ≥ P(N − 1) + 1

Where R is total number of resources,
P is the number of processes, and
N is the max need for each resource.4 ≥ 3(N − 1) + 1 3 ≥ 3(N − 1) 1 ≥ (N − 1) N ≤ 2

Therefore, the largest value of K that will always avoid deadlock is 2.