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What is a deadlock in an operating system?. A process running out of memory. A set of processes where each is waiting for a resource held by another , forming a cycle. A process being preempted involuntarily. A system crash due to resource overload.

Which of the following is NOT a necessary condition for a deadlock?. Mutual exclusion. Hold and wait. Preemption. Circular wait.

In a resource-allocation graph, what does a request edge represent?. A resource allocated to a process. A process waiting for a resource. A resource type with multiple instances. A process releasing a resource.

What does the presence of a cycle in a resource-allocation graph indicate when each resource type has only one instance ?. No deadlock. Guaranteed deadlock. Possible deadlock. safe state.

Which condition does the deadlock prevention strategy of imposing a total ordering of resources target ?. Mutual exclusion. Hold & Wait. No Preemption. Circular wait.

In the Banker's Algorithm , what does the need matrix represent?. Resources currently allocated. Maximum resources a process may request. Resources a process still needs to complete. Available resources in the system.

What happens if a process's request exceeds its declared maximum need in the Banker's Algorithm ?. The request is granted. An error is raised. The process waits indefinitely. The system enters an unsafe state.

A system is in a safe state if: A deadlock is currently occuring. There exists a sequence of processes that can complete without deadlock. All resources are fully allocated. A cycle exists in the resource-allocation graph.

What is a claim edge in a resource-allocation graph for deadlock avoidance?. A solid line indicating resource allocation. A dashed line indicating potential future requests. An edge between 2 processes. An edge indicating resource release.

In the deadlock detection algorithm , what does it mean if Finish[i] = false after execution?. Process (P_i) is safe. Process (P_i) is deadlocked. Process (P_i) has no allocated resources. Process (P_i) has completed.

Which method allows the system to enter a deadlock state and then address it. Deadlock prevention. Deadlock avoidance. Deadlock detection and recovery. Resource Preemption.

What is a key disadvantage of deadlock prevention?. High computational overhead. Resource underutilizaiton. Frequent deadlocks. Inability to detect deadlocks.

In the mutex lock example , why does a deadlock occur?. Threads acquire locks in the same order. Threads acquire locks in different orders. Only one mutex is used. The system preempts resources.

What is the purpose of the wait-for graph in deadlock detection?. To allocate resources. To identify cycles among processes. To prevent circular wait. To track resource instances.

How does the Banker's Algorithm ensure a safe state?. By preempting resources. By simulating resource allocation & checking for a safe sequence. By ignoring deadlocks. By ordering resource requests.

what is a possible recovery action from a deadlock?. Grant all resource requests. Abort one or more processes. ignore the deadlock. increase resource instances.

In a resource-allocation graph, an assignment edge points from: Process to resource. Resource to process. Process to Process. Resource to resource.

What happens if a request causes a cycle in the resource-allocation graph algorithm ?. The request is granted. The request is denied. The system terminates all processes. The system enters a safe state.

Which resource type can avoid mutual exclusion to prevent deadlocks?. Printers. Read-only files. Memory space. CPU cycles.

What is the complexity of the deadlock detection algorithm for multiple resource instances ?/. O(n). O(m*n^2). O(n^2). O(m*n).

In the Banker's algorithm example, why is the sequence <P1,P3,P4,P2,P0> safe?. All processes have no need. Each process can be allocated resources in order. No resources are allocated. A cycle exists.

What is a key factor in choosing a process to terminate for deadlock recovery?. Process Priority. Resource availability. System memory size. Number of resource in the syste.

What does the Available vector represent in the Banker's Algorithm?. Maximum resources needed. Resources currently free. Resources allocated to processes. Resources request by processes.

Why might a system ignore deadlocks , as in UNIX?. Deadlocks are impossible. Deadlocks are rare and detection is costly. Deadlocks are always prevented. Deadlocks improve performance.

In the transaction example with lock ordering , what prevents deadlocks?. Random lock acquisition. Consistent lock order based on account IDs. Preempting locks. Allowing multiple lock acquisitions.

What indicates a deadlock in a wait-for graph?. No edges. A cycle among processes. Multiple resource instances. No processes.

What is a disadvantage of resource preemption for deadlock recovery ?. it always causes deadlock. it may lead to starvation. it increases resource availability. it prevents process termination.

in the detection algorithm example , what happens when P2 requests an additional C instance?. The system remains safe. A deadlock occurs. All processes complete. Resources are preempted.

What is the purpose of the Finish Vector in the Safety Algorithm (Banker's Algorithm)?. To track allocated resources. To indicate whether a process can complete. To store maximum needs. to count available resources.

Why is the resource-allocation graph algorithm less practical for systems with multiple resource instances?. It cannot detect cycles. It requires prior knowledge of max needs. It is computationally expensive for complex graphs. it always prevents deadlocks.