【Python】python3.x 线程池 初探

#!/usr/bin/env python
# -*- encoding: utf-8 -*-
'''
@File    :   thread_test.py
@Time    :   2019/06/14 16:13:56
@Author  :   Ni Dazhong 
@Version :   1.0
@Desc    :   use python3.x
'''

from concurrent.futures import ProcessPoolExecutor, ThreadPoolExecutor, wait
import os, time, random, logging


logging.basicConfig(
    level    = logging.DEBUG,
    format   = '%(asctime)s %(levelname)s %(process)d --- [%(threadName)s] %(filename)s %(funcName)s %(lineno)d : %(message)s',
    datefmt  = '%Y-%m-%d %H:%M:%S',
)

def run_task(identifier, sleep_time):
    logging.info("task %s running ..."%(identifier))
    time.sleep(sleep_time) # 模拟方法执行时间
    return sleep_time



if __name__ == "__main__":
    start_time = time.time()
    executor = ThreadPoolExecutor(max_workers=3)

    tasks = []

    for i in range(5):
        random_sleep = random.randint(1,5)
        task = executor.submit(run_task, i, random_sleep)


        task_info = {}
        task_info["identifier"] = i
        task_info["random_sleep"] = random_sleep
        task_info["task"] = task

        tasks.append(task_info)
        
    print(wait([t["task"] for t in tasks], 4)) # wait方法等待4 秒查看线程运行状态

    for t in tasks:
        print("task{} random_sleep {}s, isDone: {} ".format(t["identifier"], t["random_sleep"], t["task"].done()))

运行结果

$ python thread_test.py
2019-06-14 17:19:13 INFO 52688 --- [ThreadPoolExecutor-0_0] thread_test.py run_task 22 : task 0 running ...
2019-06-14 17:19:13 INFO 52688 --- [ThreadPoolExecutor-0_1] thread_test.py run_task 22 : task 1 running ...
2019-06-14 17:19:13 INFO 52688 --- [ThreadPoolExecutor-0_2] thread_test.py run_task 22 : task 2 running ...
2019-06-14 17:19:14 INFO 52688 --- [ThreadPoolExecutor-0_0] thread_test.py run_task 22 : task 3 running ...
2019-06-14 17:19:16 INFO 52688 --- [ThreadPoolExecutor-0_2] thread_test.py run_task 22 : task 4 running ...
DoneAndNotDoneFutures(done={<Future at 0x30d8b10 state=finished returned int>, <Future at 0x30e76b0 state=finished returned
int>}, not_done={<Future at 0x30e7b10 state=running>, <Future at 0x30e7550 state=running>, <Future at 0x30e7b50 state=running>})
task0 random_sleep 1s, isDone: True
task1 random_sleep 5s, isDone: False
task2 random_sleep 3s, isDone: True
task3 random_sleep 4s, isDone: False
task4 random_sleep 4s, isDone: False

结果分析
代码中指定线程池只有3个可用线程， 可见打印日志也只有ThreadPoolExecutor-0_0/1/2 三个线程， 其中主线程wait 了4买哦