p46

import logging
import threading
from concurrent.futures import ThreadPoolExecutor  # Python 3.2
import time
import random

counter = 0
lock_counter = threading.Lock()


# Test function
def test(count):
    global counter
    global lock_counter
    threadname = threading.current_thread().name
    # logging.info(f'Starting: {threadname}')

    for x in range(count):
        logging.info(f'Count: {threadname} += {count}')

        # The global interpreter lock (GIL) in action
        counter = counter + 1

        # Locking
        # lock_counter.acquire()
        # lock_counter.acquire() #deadlock - waiting on resources
        # try:
        #    counter += 1
        # finally:
        #    lock_counter.release()

    # logging.info(f'Completed: {threadname}')


# Main function
def main():
    logging.basicConfig(format='%(levelname)s - %(asctime)s.%(msecs)03d: %(message)s',
                        datefmt='%H:%M:%S',
                        level=logging.DEBUG)
    logging.info('App Start')

    # initialize two workers.
    # initialize 4 iterations, in each calling the test function with a random value.
    # increment the global counter by 1 for 'random value' times..


    workers = 100
    with ThreadPoolExecutor(max_workers=workers) as ex:
        val = 10000
        results = [ex.submit(test, val) for x in range(workers * 2)]

    print(f'Counter: {counter}')
    logging.info('App Finished')


if __name__ == "__main__":
    main()