Virtual Labs

Lamport’s algorithm

What is the main purpose of Lamport's algorithm in distributed systems?

a: To provide fault tolerance during process crashes Explanation

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b: To ensure only one process can access the critical section at a time Explanation

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c: To synchronize clocks across all processes in the system Explanation

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d: To maximize throughput in distributed systems Explanation

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How does Lamport's algorithm resolve conflicts when two processes request the critical section simultaneously?

a: By using a round-robin approach to give each process equal time Explanation

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b: By comparing the timestamps of the requests and allowing the process with the smaller timestamp to enter Explanation

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c: By randomly choosing which process gets to enter Explanation

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d: By blocking all requests until the first process finishes executing Explanation

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What type of clock does Lamport's algorithm use to order events in a distributed system?

a: Real-time clock Explanation

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b: Physical clock Explanation

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c: Logical clock Explanation

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d: Global clock Explanation

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Which of the following is **not** a feature of Lamport's algorithm for mutual exclusion?

a: It ensures that only one process accesses the critical section at any time Explanation

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b: It requires all processes to send messages to each other to request entry into the critical section Explanation

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c: It resolves conflicts based on process priorities set by physical clocks Explanation

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d: It guarantees that all processes eventually enter the critical section Explanation

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In Lamport's algorithm, what must a process do before entering the critical section?

a: Wait for a timeout Explanation

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b: Send a request to all other processes and wait for a reply Explanation

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c: Increment its clock and enter immediately Explanation

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d: Wait for a process to release the critical section Explanation

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What happens when a process releases the critical section in Lamport's algorithm?

a: It sends a message to all other processes indicating that the critical section is now available Explanation

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b: It sends a message only to the process that requested last Explanation

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c: It automatically enters the critical section again Explanation

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d: It waits for the next process to request the critical section Explanation

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What happens when two processes send requests with identical logical timestamps in Lamport's algorithm?

a: The system crashes due to timestamp conflict Explanation

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b: Both processes are allowed to enter the critical section simultaneously Explanation

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c: The tie is broken using process IDs, with the lower ID getting priority Explanation

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d: The requests are queued randomly Explanation

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In Lamport's algorithm, what is the significance of maintaining a request queue at each process?

a: To store messages temporarily when the network is slow Explanation

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b: To ensure requests are processed in timestamp order for correctness Explanation

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c: To reduce memory usage by batching requests Explanation

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d: To implement load balancing across processes Explanation

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Why must a process wait for replies from ALL other processes before entering the critical section in Lamport's algorithm?

a: To ensure network reliability Explanation

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b: To prevent deadlock scenarios Explanation

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c: To guarantee that no other process has an earlier timestamp request Explanation

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d: To maintain load balance across the system Explanation

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