多线程操作同一个全局变量

多线程操作同一变量无参数版 非GIL

import threading 
from time import sleep
from datetime import datetime


date_time_format = '%y-%m-%d %H:%M:%S'

def date_time_str(date_time):
    return datetime.strftime(date_time, date_time_format)

global_count = 0

def add():
    global global_count
    global_count = global_count + 1

def main():
    print(f'---all threads start : :{date_time_str(datetime.now())}')
    threads = []
    n_loops = range(10)
    #
    for i in n_loops:
        t = threading.Thread(target=add)
        threads.append(t)

    for i in n_loops:      # start threads
        threads[i].start()

    for i in n_loops:      # wait for all
        threads[i].join()    # threads to finish

    print(f'---all threads finished :{date_time_str(datetime.now())}')

if __name__ == '__main__':
    main()
    print(global_count)

带一个参数版本 非GIL

import threading 
from time import sleep
from datetime import datetime


date_time_format = '%y-%m-%d %H:%M:%S'

def date_time_str(date_time):
    return datetime.strftime(date_time, date_time_format)

global_count = 0

def add(step = 10):
    global global_count
    global_count = global_count + step

def main():
    print(f'---all threads start : :{date_time_str(datetime.now())}')
    threads = []
    n_loops = range(10)
    #
    for i in n_loops:
        t = threading.Thread(target=add,args=(i+1,))
        threads.append(t)

    for i in n_loops:      # start threads
        threads[i].start()

    for i in n_loops:      # wait for all
        threads[i].join()    # threads to finish

    print(f'---all threads finished :{date_time_str(datetime.now())}')

if __name__ == '__main__':
    main()
    print(global_count)

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