Deadlock

Question 1

Can be taken away from a process without any side effects

Answer 1

preemptable resource

Question 2

Cannot be taken away from current process without any side effects

Answer 2

nonpremptable resource

Question 3

Each resource is either currently assigned to one process or available

Answer 3

mutual exclusion condition

Question 4

Process currently holding resources that were granted earlier can still request new resources

Answer 4

hold and wait condition

Question 5

Resources previously granted cannot be forcibly taken away from a process

Answer 5

no-premption condition

Question 6

Must be two or more processes which are waiting for a resource held by another process

Answer 6

Circular wait condition

Question 7

• Ignore problem and hope it resolves itself
• detection and recovery
• dynamic avoidance by careful resource allocation
• prevention by not allowing one of the four deadlock conditions to exist

Answer 7

Strategies with deadlock

Question 8

Take away a resource from current owner and give to another process

Answer 8

Recovery through preemption

Question 9

Checkpoint system state. When deadlock detected, rollback process to checkpoint before it acquired resource

Answer 9

Recovery through rollback

Question 10

Kill process to break cycle. Attempt to select process that is safest to kill

Answer 10

Recovery through killing

Question 11

Some schedling order in which every process can be ran to completion

Answer 11

safe state

Question 12

Do not imply deadlock, but opposite implies lack of deadlock

Answer 12

nonsafe states

Question 13

Assure that at least one condition of deadlock is never satisfied

Answer 13

deadlock prevention

Question 14

Processes can request resource whenever, but all requests must be made in defind order

Answer 14

global ordering of processes to attack circular wait