Understanding Deadlock in Operating Systems

What is a deadlock in an operating system?

• A situation where a process runs indefinitely without completing

• A situation where two or more processes are blocked forever, each waiting for a resource held by the other

• A situation where the CPU is idle due to lack of processes

• A situation where memory is fully utilized by a single process

Which of the following is NOT one of the four necessary conditions for a deadlock to occur?

• Mutual Exclusion

• Hold and Wait

• Preemption

• Circular Wait

In a Resource Allocation Graph (RAG), what does a cycle in the graph indicate?

• That all processes have completed execution

• That resources are being shared efficiently

• That a deadlock may exist if each resource has only one instance

• That the CPU scheduling is optimal

Which deadlock prevention technique works by ensuring that a process must request all the resources it needs at once before it begins execution?

• Eliminating Circular Wait

• Eliminating Hold and Wait

• Eliminating Mutual Exclusion

• Eliminating No Preemption

• No deadlock exists because there are enough resources

• A deadlock exists because there is a circular wait among all three processes

• A deadlock may exist but cannot be confirmed without more information

• The system is in a safe state

The Banker's Algorithm is used for which of the following purposes in operating systems?

• Deadlock Recovery by killing processes

• Deadlock Detection by building a wait-for graph

• Deadlock Avoidance by ensuring the system stays in a safe state

• Deadlock Prevention by eliminating mutual exclusion

• No, because no process can complete with only 1 available instance

• Yes, because the total allocated resources are less than the maximum

• No, because the Banker's Algorithm does not apply to single resource types

Which deadlock recovery strategy involves rolling back one or more processes to a previously saved state to break the deadlock?

• Resource Preemption

• Process Termination

• Process Rollback

• Resource Reallocation

• All five processes are deadlocked; terminate all processes simultaneously

A system designer is building a real-time operating system where processes must frequently share printers and disk drives. The designer wants to prevent deadlocks by eliminating the "Circular Wait" condition. Which of the following strategies best achieves this, and what is a potential drawback of this approach?

• Assign a unique priority number to each process; drawback is that low-priority processes may starve

• Impose a total ordering on all resource types and require processes to request resources in increasing order; drawback is that it may lead to inefficient resource utilization

• Allow processes to request all resources at once before execution; drawback is that it increases the chance of mutual exclusion

• Preempt resources from processes when needed; drawback is that it may cause data inconsistency