How do I implement semaphores in code?

What are semaphores and how do I use them in my code?

Semaphores are synchronization tools used to control access to a common resource in concurrent programming. They help prevent race conditions.

Can you show me a simple example of semaphore implementation in Python?

Sure! Here's a basic example using the threading module:

import threading

# Create a semaphore with a limit of 2
semaphore = threading.Semaphore(2)

def access_resource(thread_id):
    print(f'Thread {thread_id} is trying to access the resource.')
    with semaphore:
        print(f'Thread {thread_id} has accessed the resource.')
        # Simulate resource access
        time.sleep(2)
    print(f'Thread {thread_id} has released the resource.')

# Create multiple threads
threads = [threading.Thread(target=access_resource, args=(i,)) for i in range(5)]

# Start the threads
for thread in threads:
    thread.start()

# Wait for all threads to complete
for thread in threads:
    thread.join()

What happens if I set the semaphore limit too high?

If the semaphore limit is set too high, it may lead to resource contention, where too many threads access the resource simultaneously, potentially causing performance issues or even deadlocks.