Virtual Labs

Maekawa's Quorum-Based Mutual Exclusion Algorithm

What is the primary purpose of a quorum-based mutual exclusion algorithm?

a: To ensure that only one process can access a critical section at a time. Explanation

Explanation

b: To allow multiple processes to access a critical section simultaneously. Explanation

Explanation

c: To reduce the number of messages exchanged. Explanation

Explanation

d: To eliminate the need for a central coordinator. Explanation

Explanation

In Maekawa's algorithm, a process sends a request message to which set of processes?

a: All processes in its own quorum. Explanation

Explanation

b: All processes in the system. Explanation

Explanation

c: A randomly selected subset of processes. Explanation

Explanation

d: The central coordinator. Explanation

Explanation

A process can enter the critical section only after it receives a grant message from which set of processes?

a: All processes in its quorum. Explanation

Explanation

b: A majority of processes in the system. Explanation

Explanation

c: At least one other process. Explanation

Explanation

d: The central coordinator. Explanation

Explanation

What is the main advantage of Maekawa's algorithm over Lamport's and Ricart-Agrawala's algorithms?

a: It has a lower message complexity. Explanation

Explanation

b: It is simpler to implement. Explanation

Explanation

c: It is completely fault-tolerant. Explanation

Explanation

d: It does not require timestamps. Explanation

Explanation

The condition that any two quorums have a non-empty intersection ensures which property of mutual exclusion?

a: Safety Explanation

Explanation

b: Liveness Explanation

Explanation

c: Fairness Explanation

Explanation

d: Freedom from starvation Explanation

Explanation

If a process fails in Maekawa's algorithm, what is the potential consequence?

a: The system may deadlock. Explanation

Explanation

b: The critical section may be accessed by multiple processes simultaneously. Explanation

Explanation

c: The failed process will be automatically removed from all quorums. Explanation

Explanation

d: The algorithm will continue to function correctly without any issues. Explanation

Explanation

How does Maekawa's algorithm handle concurrent requests for the critical section?

a: It uses timestamps to order the requests. Explanation

Explanation

b: It grants access on a first-come, first-served basis. Explanation

Explanation

c: It can lead to deadlock if not handled carefully. Explanation

Explanation

d: It uses a central coordinator to resolve conflicts. Explanation

Explanation

To build a fault-tolerant version of Maekawa's algorithm, what modification could be made?

a: Increase the size of the quorums. Explanation

Explanation

b: Use a dynamic quorum system. Explanation

Explanation

c: Add a failure detector and a recovery mechanism. Explanation

Explanation

d: All of the above. Explanation

Explanation

Compared to a centralized mutual exclusion algorithm, Maekawa's algorithm offers better:

a: Scalability and reliability. Explanation

Explanation

b: Simplicity and ease of implementation. Explanation

Explanation

c: Performance in low-contention scenarios. Explanation

Explanation

d: Guaranteed freedom from deadlock. Explanation

Explanation