[Solved] Consider a producer-consumer system with a buffer s... If the consumer attempts to consume an item immediately after system start, what happens to the consumer thread when using semaphores correctly? | Operating Systems

Operating Systems - Producer-Consumer Problem Using Semaphores

Consider a producer-consumer system with a buffer size of 5, initially empty. If the consumer attempts to consume an item immediately after system start, what happens to the consumer thread when using semaphores correctly?

AThe consumer blocks on the 'full' semaphore until the producer produces an item

BThe consumer proceeds and consumes a default or garbage item from the buffer

CThe consumer acquires the mutex and waits inside the critical section

DThe consumer causes a buffer overflow error

Step-by-Step Solution

Solution:

Step 1: Initial semaphore values
'full' semaphore is initialized to 0, indicating no items to consume.
Step 2: Consumer behavior
Consumer performs P (wait) on 'full'; since it's 0, consumer blocks until producer signals.
Step 3: Evaluate other options
Consuming garbage (B) violates semaphore logic; acquiring mutex (C) requires 'full' semaphore; buffer overflow (A) is unrelated.
Final Answer:
Option A -> Option A
Quick Check:
Consumer blocks on empty buffer until producer signals [OK]

Quick Trick: Consumer blocks on 'full' semaphore when buffer empty [OK]

Common Mistakes:

MISTAKES

Assuming consumer can consume without items
Confusing mutex with semaphore blocking
Ignoring initial semaphore values

Trap Explanation:

PITFALL

Candidates often think consumer proceeds regardless of buffer state, ignoring semaphore blocking.

Interviewer Note:

CONTEXT

Checks understanding of semaphore initialization and blocking behavior.

Master "Producer-Consumer Problem Using Semaphores" in Operating Systems

2 interactive learning modes - each teaches the same concept differently

Solution Trace

More Operating Systems Quizzes

If the consumer attempts to consume an item immediately after system start, what happens to the consumer thread when using semaphores correctly?

Step 1: Initial semaphore values

Step 2: Consumer behavior

Step 3: Evaluate other options

Final Answer:

Quick Check:

Want More Practice?