Python multiprocessing and thread

Thread

import threading
from datetime import datetime


def show(n, s):
    total = 0
    from random import random
    for i in range(n):
        total += i
    print('total={} start={} end={}'.format(total, str(s), str(datetime.now())))

if __name__ == "__main__":
    max = 1000

    jobs = []
    for index in range(4):
        s = datetime.now()
        jobs.append(threading.Thread(target=show, args=[max, s]))

    for index in range(4):
        jobs[index].start()

    for index in range(4):
        jobs[index].join()

total=499500 start=2018-08-13 14:32:26.588980 end=2018-08-13 14:32:26.590985
total=499500 start=2018-08-13 14:32:26.588980 end=2018-08-13 14:32:26.591987
total=499500 start=2018-08-13 14:32:26.589481 end=2018-08-13 14:32:26.592990
total=499500 start=2018-08-13 14:32:26.589481 end=2018-08-13 14:32:26.593993

Multiprocessing

import multiprocessing
from datetime import datetime


def show(n, s):
    total = 0
    for i in range(n):
        total += i
    print('total={} start={} end={}'.format(total, str(s), str(datetime.now())))

if __name__ == "__main__":
    max = 1000

    jobs = []
    for index in range(4):
        s = datetime.now()
        jobs.append(multiprocessing.Process(target=show, args=[max, s]))

    for index in range(4):
        jobs[index].start()

    for index in range(4):
        jobs[index].join()

output

total=499500 start=2018-08-13 14:24:28.087562 end=2018-08-13 14:24:28.803968
total=499500 start=2018-08-13 14:24:28.088063 end=2018-08-13 14:24:29.428128
total=499500 start=2018-08-13 14:24:28.088063 end=2018-08-13 14:24:30.018699
total=499500 start=2018-08-13 14:24:28.088063 end=2018-08-13 14:24:30.587712