OPERATING SYSTEM

A computer system has 9 tape drives, with processes competing for them. Each process may need 3 tape drives. The maximum value of n for which the system is guaranteed to be deadlock free is
(i) 9
(ii) 7
(iii) 4
(iv) 6

What is the drawback of banker's algorithm?
(i) in advance processes rarely know how much resource they will need
(ii) the number of processes changes as time progresses
(iii) resource once available can disappear
(iv) all of the mentioned

When a process waits indefinitely for some resources which are being used by other processes, it is called
(i) Starvation
(ii) Demand Paging
(iii) Segmentation
(iv) None of the above

If the wait for graph contains a cycle, then
(i) a deadlock does not exist
(ii) a deadlock exists
(iii) the system is in a safe state
(iv) either deadlock exists or system is in a safe state

Which of the following conditions is required for deadlock to be possible?
(i) Mutual exclusion
(ii) A process may hold allocated resources while awaiting assignment of other resources
(iii) No resource can be forcibly removed from a process holding it
(iv) All of the above

Which one of the following is the deadlock avoidance algorithm?
(i) Banker's algorithm
(ii) Round-robin algorithm
(iii) Elevator algorithm
(iv) Karn's algorithm

Describe the techniques for recovery from deadlock? Explain briefly resource allocation graph with examples.

What do you understand by deadlock? Discuss the methods to avoid deadlock.

Clearly justify why deadlocks cannot arise in a bounded buffer producers-consumers system.

State and explain the necessary and sufficient conditions for a deadlock.

Consider a system consisting of four resources of the same type that are shared by three processes, each of which needs at most two resources. Show that the system is deadlock-free.

Compare and contrast Deadlock Prevention and Deadlock Avoidance. Can a system be in a state that is neither deadlock nor safe? If so, give an example. If not, prove that all states are either deadlock or safe.

Define deadlock. List four necessary conditions for occurrence of deadlock.

A system contains six units of resource, and n processes that use the resource. What is the maximum value of n for which the system will be deadlock free if the maximum requirement of each process is 3?