Deadlock Prevention and Recovery in Distributed Systems: A Comprehensive Guide

Question 1

Which of the following conditions is NOT necessary for a deadlock to occur in a distributed system?

Accepted Answer

Resource hierarchy

Answer

Mutual exclusion

Answer

Hold and wait

Answer

Circular waiting

Question 2

Which deadlock prevention strategy ensures that processes can only hold resources they actively need?

Accepted Answer

Banker's algorithm

Answer

Resource ordering

Answer

Wound-wait

Answer

Timeout

Question 3

Which deadlock recovery technique involves terminating a process and releasing its held resources?

Accepted Answer

Kill

Answer

Preemption

Answer

Rollback

Answer

Restart

Question 4

Which of the following is a potential drawback of using a timeout-based deadlock detection algorithm?

Accepted Answer

False positives leading to unnecessary process termination

Answer

Increased resource utilization due to additional monitoring

Answer

Reduced performance caused by frequent timeout checks

Answer

Increased complexity in algorithm implementation

Question 5

Which of the following is NOT an advantage of using a centralized deadlock detection algorithm?

Accepted Answer

Reduced computation costs due to efficient resource management

Answer

Lower network traffic due to reduced message passing

Answer

Faster detection latency due to centralized monitoring

Answer

Increased detection accuracy due to global visibility

Question 6

Which of the following algorithms is specifically designed to prevent deadlocks in a distributed system?

Accepted Answer

Banker's algorithm

Answer

Round-robin scheduling

Answer

Wound-wait algorithm

Question 7

What is the primary purpose of deadlock detection algorithms?

Accepted Answer

Identify the processes involved in a deadlock

Answer

Prevent deadlocks from occurring

Answer

Recover the system from a deadlock

Answer

Avoid resource starvation

Question 8

Which metric is commonly used to assess the efficiency of deadlock prevention algorithms?

Accepted Answer

Deadlock avoidance overhead

Answer

Deadlock detection time

Answer

Deadlock recovery time

Answer

Resource utilization

Question 9

Which of these is NOT a fundamental condition for a deadlock to occur in a distributed system?

Accepted Answer

Resource starvation

Answer

Mutual exclusion

Answer

Hold and wait

Answer

Circular wait

Question 10

Which condition is NOT necessary for a deadlock to occur in a distributed system?

Accepted Answer

Sufficient system resources

Answer

Mutual exclusion

Answer

Hold and wait

Answer

Circular wait

Question 11

Which deadlock prevention algorithm assigns all resources needed by a process to that process before it starts execution?

Accepted Answer

Resource ordering

Answer

Hold-and-wait

Answer

Wound-wait

Answer

Timestamp ordering

Question 12

Which deadlock detection algorithm utilizes depth-first search to identify cycles in the resource allocation graph?

Accepted Answer

Floyd's cycle detection algorithm

Answer

Basic detection algorithm

Answer

Banker's algorithm

Answer

Dijkstra's algorithm

Question 13

Which of the following is NOT a technique for recovering from a deadlock?

Accepted Answer

Deadlock avoidance

Answer

Process termination

Answer

Resource preemption

Answer

Resource rollback

Question 14

Which characteristic defines a deadlock-free system?

Accepted Answer

Absence of cycles in the resource allocation graph

Answer

Abundant resources to fulfill all requests

Answer

Employment of deadlock prevention algorithms

Answer

Insensitivity to timing conditions

Question 15

In a distributed system, a set of processes that are waiting for each other to release resources they are holding is known as a:

Accepted Answer

Deadlock

Answer

Livelock

Answer

Starvation

Answer

Race condition

Question 16

In Banker's algorithm, a safe sequence is a sequence of processes that can be run without causing a deadlock.

Accepted Answer

True

Answer

False

Question 17

What is the primary distinction between deadlock prevention and deadlock avoidance?

Accepted Answer

Prevention detects deadlocks, while avoidance aims to prevent them from occurring.

Answer

Prevention restricts resource allocation, while avoidance does not.

Answer

Prevention is more efficient than avoidance.

Answer

Avoidance requires more system information than prevention.

Question 18

When recovering from a deadlock, what should be the initial step?

Accepted Answer

Identifying the deadlocked processes

Answer

Terminating one or more deadlocked processes

Answer

Rolling back the state of the deadlocked processes

Answer

Restarting the entire system

Question 19

What is a primary goal of a deadlock detection algorithm?

Accepted Answer

Accurately and efficiently identifying deadlocks

Answer

Resolving deadlocks by terminating processes or rolling back transactions

Answer

Preventing deadlocks from occurring in the first place

Answer

Monitoring the system for potential deadlocks

Question 20

What advantage does a centralized deadlock detection algorithm offer?

Accepted Answer

Provides a holistic view of the system, aiding in deadlock identification

Answer

Lower overhead compared to distributed algorithms

Answer

More efficient in detecting deadlocks involving multiple resources

Answer

More resilient to failures than distributed algorithms

Question 21

In the context of deadlock prevention in distributed systems, what is the distinction between a safe state and an unsafe state?

Accepted Answer

A safe state allows for a sequence of resource allocations to avoid deadlocks, while an unsafe state does not.

Answer

An unsafe state allows for a sequence of resource allocations to avoid deadlocks, while a safe state does not.

Answer

A safe state is a state with no possible deadlocks, whereas an unsafe state has potential deadlocks.

Answer

A safe state has potential deadlocks, whereas an unsafe state has no possible deadlocks.

Question 22

Which design principle is essential for preventing deadlocks in distributed systems?

Accepted Answer

Acquire resources in a predefined order

Answer

Request all necessary resources at once

Answer

Permit processes to forcibly take resources from one another

Question 23

Which of the following algorithms is specifically designed for deadlock detection in distributed systems?

Accepted Answer

Chandy-Lamport

Answer

Resource allocation graph

Answer

Waiter-victim

Answer

Time-stamping

Question 24

What is the primary objective of deadlock avoidance algorithms?

Accepted Answer

Preventing processes from entering a state where they could potentially deadlock

Answer

Allowing deadlocks to occur and then recovering from them

Answer

Establishing a hierarchical structure among processes to avoid starvation

Answer

Utilizing timeouts to ensure processes do not hold resources indefinitely

Question 25

Which recovery technique involves terminating one or more deadlocked processes to break the deadlock?

Accepted Answer

Killing

Answer

Rollback

Answer

Starvation

Answer

Timeouts

Question 26

What is the primary purpose of a resource allocation graph in deadlock detection?

Accepted Answer

Providing a visual representation of resource allocation within a system

Answer

Detecting deadlocks using the Banker's algorithm

Answer

Optimizing resource utilization

Answer

Implementing deadlock prevention algorithms

Question 27

Which condition is NOT essential for a deadlock to occur in a system?

Accepted Answer

Resource ordering

Answer

Mutual exclusion

Answer

Hold and wait

Answer

No preemption

Question 28

What is a fundamental distinction between deadlock prevention and deadlock avoidance strategies?

Accepted Answer

Prevention aims to eliminate the possibility of deadlocks, while avoidance only reduces their likelihood

Answer

Prevention is suitable for static systems, while avoidance is suitable for dynamic systems

Answer

Prevention requires more system information than avoidance

Answer

Prevention is inherently more computationally intensive than avoidance

Question 29

Which deadlock detection algorithm utilizes timestamps assigned to resource requests to establish the sequence in which processes obtained resources?

Accepted Answer

Timestamp Ordering

Answer

Wound-Wait

Answer

Banker's Algorithm

Answer

Resource Allocation Graph

Question 30

Which of the following is a necessary condition for a deadlock to occur?

Accepted Answer

All processes are waiting permanently for resources held by others

Answer

No two processes are holding the same resource

Answer

All processes are running at the same priority

Answer

The system has sufficient resources for all processes

Question 31

What is the key difference between deadlock detection and deadlock avoidance?

Accepted Answer

Detection identifies deadlocks after they occur, while avoidance prevents them from happening

Answer

Detection is used in systems with static resources, while avoidance is used in systems with dynamic resources

Answer

Detection is more efficient than avoidance

Question 32

Which of the following is an example of a deadlock avoidance algorithm?

Accepted Answer

Banker's Algorithm

Answer

Dijkstra's Algorithm

Answer

Round Robin Algorithm

Question 33

What is the central mechanism of the Banker's Algorithm?

Accepted Answer

Predicting whether a resource request can be granted safely without leading to a deadlock

Answer

Limiting processes from requesting resources beyond their need

Answer

Determining deadlocks by searching for cycles in a resource allocation graph

Question 34

Which of the following is a commonly used strategy for deadlock recovery?

Accepted Answer

Terminating one or more processes involved in the deadlock

Answer

Ignoring the deadlock and waiting for it to resolve naturally

Answer

Adjusting the process priorities to break the deadlock

Answer

Increasing the number of available resources in the system

Question 35

What is a primary advantage of deadlock prevention over deadlock detection?

Accepted Answer

Preventing deadlocks from occurring entirely

Answer

Applicable to systems with any number of resources

Answer

Simplicity and lower overhead

Question 36

Which condition must be met for a resource allocation graph to be considered safe?

Accepted Answer

All cycles in the graph have at least one edge directed towards an available resource

Answer

The graph contains no cycles

Answer

The graph is connected

Answer

All nodes in the graph have the same weight

Question 37

Which of the following conditions is NOT required for a deadlock to occur?

Accepted Answer

Mutual exclusion is not held

Answer

Circular wait (a cycle of processes waiting for each other)

Answer

Hold and wait (resource holding and requesting)

Answer

No preemption (resources cannot be forcibly taken)

Question 38

The Banker's algorithm is primarily used for:

Accepted Answer

Deadlock avoidance

Answer

Deadlock detection

Answer

Deadlock recovery

Answer

Deadlock prevention

Question 39

Which deadlock recovery strategy involves terminating one or more processes to break the deadlock?

Accepted Answer

Process termination

Answer

Resource preemption (taking a resource from a process)

Answer

None of the above

Answer

Rollback (restoring processes to a previous safe state)

Question 40

Which of these is NOT a potential drawback of using deadlock prevention techniques?

Accepted Answer

Improved system performance

Answer

Reduced system overhead

Answer

Increased system complexity

Answer

None of the above

Question 41

The Chandy-Misra-Haas algorithm is primarily used for:

Accepted Answer

Deadlock detection in distributed systems

Answer

None of the above

Answer

Deadlock recovery in real-time systems

Answer

Deadlock avoidance in centralized systems

Question 42

What is a major challenge in implementing deadlock recovery mechanisms?

Accepted Answer

Determining the minimum rollback point (to minimize work loss)

Answer

Identifying the deadlocked processes

Answer

Allocating additional resources

Answer

None of the above

Question 43

Which of the following sets of conditions is **necessary** for a system to be in a deadlock state?

Accepted Answer

Mutual Exclusion, Hold and Wait, No Preemption, Circular Wait

Answer

Exclusive Resource Access, Non-preemption, Resource Sharing, Process Termination

Answer

Mutual Exclusion, Resource Sharing, Process Creation, Resource Allocation

Answer

Resource Allocation, Process Creation, Circular Wait, Hold and Wait

Question 44

What is the key difference between deadlock **detection** and deadlock **avoidance** algorithms?

Accepted Answer

Detection algorithms identify deadlocks after they occur, while avoidance algorithms prevent deadlocks from happening.

Answer

Detection algorithms are more efficient than avoidance algorithms.

Answer

Detection algorithms are used for static systems, while avoidance algorithms are used for dynamic systems.

Answer

Avoidance algorithms are more complex to implement than detection algorithms.

Question 45

What is the primary goal of the Banker's Algorithm, a deadlock **avoidance** algorithm?

Accepted Answer

To ensure that all processes can complete their execution without encountering a deadlock.

Answer

To recover from deadlocks if they occur.

Answer

To detect deadlocks when they occur.

Answer

To optimize resource allocation for maximum system throughput.

Question 46

Which of the following is a potential **limitation** of deadlock **recovery** algorithms?

Accepted Answer

They may lead to the starvation of certain processes, where they are repeatedly rolled back and never progress.

Answer

They can prevent deadlocks from occurring in the future.

Answer

They are easy to implement and have minimal overhead.

Answer

They are always able to restore the system to a deadlock-free state.

Question 47

What is the main advantage of using a **timestamp-based** deadlock detection algorithm?

Accepted Answer

It can effectively detect deadlocks in systems where resource requests are not always known in advance, such as in distributed environments.

Answer

It is easier to implement than other deadlock detection algorithms.

Answer

It provides a precise indication of the time at which a deadlock occurred.

Answer

It is more efficient than other deadlock detection algorithms.

Question 48

Which of the following is a common approach for **deadlock prevention** in **database systems**?

Accepted Answer

Two-Phase Locking (2PL)

Answer

Chandy-Misra-Haas Algorithm

Answer

Wound-Wait Algorithm

Answer

Wait-for Graph Algorithm

Question 49

What is the primary purpose of a deadlock **recovery** algorithm?

Accepted Answer

To restore the system to a deadlock-free state by aborting or suspending processes, releasing resources, and potentially rolling back transactions.

Answer

To optimize resource allocation for maximum system throughput.

Answer

To detect deadlocks when they occur.

Answer

To prevent deadlocks from occurring in the system.

Question 50

What is the main idea behind the **Wound-Wait** Algorithm, a deadlock avoidance technique?

Accepted Answer

When a process requests a resource held by another process, the older process can 'wound' (terminate) the younger process, allowing the older process to proceed.

Answer

Processes are required to release all resources before requesting new ones.

Answer

Only older processes can make requests for resources.

Answer

Processes are assigned a priority based on their age.