GATE CSE 2007 | Deadlocks Question 16 | Operating Systems

GATE CSE 2007

MCQ (Single Correct Answer)

-0.6

A single processor system has three resource types X, Y and Z, which are shared by three processes. There are 5 units of each resource type. Consider the following scenario, where the column alloc denotes the number of units of each resource type allocated to each process, and the column request denotes the number of units of each resource type requested by a process in order to complete execution. Which of these processes will finish LAST? GATE CSE 2007 Operating Systems - Deadlocks Question 17 English

GATE CSE 2007 Operating Systems - Deadlocks Question 17 English

None of the above, since the system is in a deadlock.

GATE CSE 2006

MCQ (Single Correct Answer)

-0.6

Consider the following snapshot of a system running n processes. Process i is holding x_i instances of a resource R, for $$1 \le i \le n$$. Currently, all instances of R are occupied. Further, for all i, process i has placed a request for an additional y_i instances while holding the x_i instances it already has. There are exactly two processes p and q such that y_p = y_q = 0. Which one of the following can serve as a necessary condition to guarantee that the system is not approaching a deadlock?

$$\min ({x_p},{x_q}) < {\max _{k \ne p,q}}{y_k}$$

$${x_p} + {x_q} \ge {\min _{k \ne p,q}}{y_k}$$

$$\max ({x_p},{x_q}) > 1$$

$$\min ({x_p},{x_q}) > 1$$

GATE CSE 2005

MCQ (Single Correct Answer)

-0.6

Suppose n processes, P₁,......., P_n share m identical resource units, which can be reserved and released one at a time. The maximum resource requirement of process P_i is S_i, where S_i > 0. Which one of the following is a sufficient condition for ensuring that deadlock does not occur?

$$\forall i,{s_i} < m$$

$$\forall i,{s_i} < n$$

$$\sum\limits_{i = 1}^n {{s_i}} < \left( {m + n} \right)$$

$$\sum\limits_{i = 1}^n {{s_i}} < \left( {m \times n} \right)$$

GATE CSE 2000

MCQ (Single Correct Answer)

-0.6

Which of the following is NOT a valid deadlock prevention scheme?

Release all resources before requesting a new resource

Number the resources uniquely and never request a lower numbered resource than the last one requested.

Never request a resource after releasing any resource

Request and all required resources be allocated before execution.