OS-Deadlock

Which of the following condition is required for deadlock to be possible?

• mutual exclusion

• a process may hold allocated resources while awaiting assignment of other resources

• no resource can be forcibly removed from a process holding it

• all of the mentioned

A system is in the safe state if

• the system can allocate resources to each process in some order and still avoid a deadlock

• there exist a safe sequence

• all of the mentioned

• none of the mentioned

The circular wait condition can be prevented by

• defining a linear ordering of resource types

• using thread

• using pipes

• all of the mentioned

Which one of the following is the deadlock avoidance algorithm?

• banker’s algorithm

• round-robin algorithm

• elevator algorithm

• karn’s algorithm

A process said to be in ___________ state if it was waiting for an event that will never occur.

• Safe

• Unsafe

• Starvation

• Dead lock

A computer system has 6 tape drives, with 'n' 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

• 4

• 3

• 2

• 1

Which one of the following is a visual ( mathematical ) way to determine the deadlock occurrence?

• resource allocation graph

• starvation graph

• inversion graph

• none of the mentioned

To ensure that the hold and wait condition never occurs in the system, it must be ensured that ____________

• whenever a resource is requested by a process, it is not holding any other resources

• each process must request and be allocated all its resources before it begins its execution

• a process can request resources only when it has none

• all of the mentioned

A system has 12 magnetic tape drives and 3 processes : P0, P1, and P2. Process P0 requires 10 tape drives, P1 requires 4 and P2 requires 9 tape drives.

Process :P0 P1 P2

Maximum needs (process-wise: P0 through P2 top to bottom) :10 4 9

Currently allocated (process-wise)5 2 2

• P0, P1, P2

• P1, P2, P0

• P2, P0, P1

• P1, P0, P2

If no cycle exists in the resource allocation graph ____________

• then the system will not be in a safe state

• then the system will be in a safe state

• all of the mentioned

• none of the mentioned