QUESTION 37 Which of the algorithm(s) given below is/are NOT a type of contention-based...
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QUESTION 37
Which of the algorithm(s) given below is/are NOT a type of contention-based algorithms for mutual exclusion in operating systems?
I) Lamport's Algorithm
II) Suzuki-Kasami Algorithm
III) Ricart-Agarwala Algorithm
Show answer & explanation
Lamport's Algorithm and Ricart-Agarwala Algorithm are contention-based algorithms that use permission-based or timestamp-based approaches for mutual exclusion. Suzuki-Kasami Algorithm is a token-based (non-contention-based) algorithm where a single token is passed among processes, avoiding the contention characteristic of permission-based algorithms. Therefore, only (II) Suzuki-Kasami is NOT contention-based.
Step-by-step Derivation:
Mutual exclusion algorithms are classified into two categories:
Contention-Based Algorithms: Processes compete for access by requesting permission from other processes.
- Lamport's Bakery Algorithm (I): Uses logical clocks and timestamp ordering. Processes request access and compete for the critical section. ✓ Contention-based
- Ricart-Agarwala Algorithm (III): Uses permission-based approach where a process requests permission from all others before entering the critical section. ✓ Contention-based
Token-Based (Non-Contention) Algorithms: A single token circulates among processes; only the token holder can access the critical section.
- Suzuki-Kasami Algorithm (II): Uses a token that circulates through a logical ring structure. Only the token holder enters the critical section, eliminating contention. ✗ NOT contention-based
Answer: Only (II) Suzuki-Kasami Algorithm is NOT contention-based.
Note: Option A references (IV) which does not exist in the question; this is a transcription error in the original options.