0

When implementing Peterson's algorithm on a modern multi-core processor with relaxed memory consistency, what is the primary concern that must be addressed to ensure correctness?

hard🚀 Advanced Concept Q8 of Q15

Operating Systems - Critical Section Problem - Requirements & Peterson's Solution

When implementing Peterson's algorithm on a modern multi-core processor with relaxed memory consistency, what is the primary concern that must be addressed to ensure correctness?

AExcessive CPU usage from busy waiting

BDeadlock due to infinite waiting on flags

CMemory reordering causing visibility issues between processes

DIncorrect initialization of the turn variable

Step-by-Step Solution

Solution:

Step 1: Understand memory model
Modern multi-core processors may reorder memory operations for optimization.
Step 2: Impact on Peterson's algorithm
This reordering can cause one process to see stale values of flags or turn, violating mutual exclusion.
Step 3: Addressing the issue
Memory barriers or fences are required to enforce ordering and visibility.
Final Answer:
Option C -> Option C
Quick Check:
Memory consistency affects synchronization correctness [OK]

Quick Trick: Memory reordering breaks flag visibility without fences [OK]

Common Mistakes:

MISTAKES

Confusing deadlock with memory visibility issues
Assuming busy waiting is the main problem
Ignoring the need for memory barriers

Trap Explanation:

PITFALL

Mistaking deadlock or CPU usage as primary issues instead of memory ordering

Interviewer Note:

CONTEXT

Tests knowledge of hardware memory models affecting software synchronization

Master "Critical Section Problem - Requirements & Peterson's Solution" in Operating Systems

2 interactive learning modes - each teaches the same concept differently

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions

More Operating Systems Quizzes