Error at threaded_visits.py Ch6, Multiprocessing

[binodil]

Hi there,

Concurrency is great topic. I followed the code regarding threaded_visits.py. Authors argued that when I will run the file, I will get unexpected results. However, I am getting expected 10_000_000 value for thread_visits.

My hypothesis: There might be changes in threading standard library.
Looking for your reply!

from threading import Thread

thread_visits = 0

def visit_counter():
    global thread_visits 
    for i in range(100_000):
        # value = thread_visits
        thread_visits +=  1

if __name__ == "__main__":
    thread_count = 100
    threads = [
        Thread(target=visit_counter)
        for _ in range(thread_count)
    ]
    for thread in threads:
        thread.start()
    
    for thread in threads:
        thread.join()
    print(f"{thread_count=}, {thread_visits=}")

(my_bert) (base) sardor@Sardors-MacBook-Pro Concurrency % python3 thread_chaos.py
thread_count=100, thread_visits=10000000
(my_bert) (base) sardor@Sardors-MacBook-Pro Concurrency % python3 thread_chaos.py
thread_count=100, thread_visits=10000000
(my_bert) (base) sardor@Sardors-MacBook-Pro Concurrency % python3 thread_chaos.py
thread_count=100, thread_visits=10000000
(my_bert) (base) sardor@Sardors-MacBook-Pro Concurrency % python3 thread_chaos.py
thread_count=100, thread_visits=10000000