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GitHub Repository: jackfrued/Python-100-Days
 Path: blob/master/Day16-20/code/example22.py
Views: 729
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"""

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多进程和进程池的使用

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多线程因为GIL的存在不能够发挥CPU的多核特性

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对于计算密集型任务应该考虑使用多进程

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time python3 example22.py

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real    0m11.512s

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user    0m39.319s

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sys     0m0.169s

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"""

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import concurrent.futures

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import math

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PRIMES = [

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    1116281,

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    1297337,

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    104395303,

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    472882027,

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    533000389,

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    817504243,

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    982451653,

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    112272535095293,

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    112582705942171,

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    112272535095293,

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    115280095190773,

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    115797848077099,

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    1099726899285419

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] * 5

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def is_prime(n):

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    """判断素数"""

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    if n % 2 == 0:

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        return False

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    sqrt_n = int(math.floor(math.sqrt(n)))

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    for i in range(3, sqrt_n + 1, 2):

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        if n % i == 0:

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            return False

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    return True

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def main():

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    """主函数"""

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    with concurrent.futures.ProcessPoolExecutor() as executor:

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        for number, prime in zip(PRIMES, executor.map(is_prime, PRIMES)):

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            print('%d is prime: %s' % (number, prime))

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if __name__ == '__main__':

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    main()

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