Python | 事半功倍怎么来呢

"""
跨平台
提供了一个 Process 类来描述进程对象。创建子进程，只需要传入一个执行函数和函数的参数
，即可完成一个 Process 实例创建，用 start() 方法启动进程，用 join() 方法实现进程
间的同步
"""
import os
from multiprocessing import Process


#子进程要执行的代码
def run_proc(name):
    print('Child process %s (%s) Running ...' % (name,os.getpid())) # os.getpid() 获取进程 id


if __name__ == '__main__':
    print('Parent process %s.' % os.getpid())
    for i in range(5):
        p = Process(target=run_proc,args=(str(i),)) # 第一个参数为任务函数，第二个为传进去的任务参数
        print('Process will start.')
        p.start()
    p.join()
    print('Process end.')

"""
Pool 可以提供指定数量的进程供用户调用，默认大小是 CPU 的核数。但有新的请求提交到
Pool 中时，池还没有满，就会创建一个新的进程用来执行该请求；如已达到最大数，就会等待
知道有进程结束，才会创建新的进程来处理他
"""
from multiprocessing import Pool
import os,time,random


def run_task(name):
    print('Task %s (pid = %s) is running ...' % (name,os.getpid()))
    time.sleep(random.random() * 3)
    print('Task %s end.' % name)


if __name__ == '__main__':
    print('Current process %s.' % os.getpid())
    p = Pool(processes=3)
    for i in range(5):
        p.apply_async(run_task,args=(i,)) #添加进程任务，i 为传进去的进程任务的参数
        pass
    print('Waiting for all subprocesses done...')
    p.close() #不再添加新进程
    p.join() #等待所有子进程执行完毕,调用之前必须先调用 close(),针对 Pool 对象
    print('All subprocesses done.')

"""
把一个函数传入并创建 Tread 实例
"""
import random
import time,threading


#新线程执行的代码
def thread_run(urls):
    print('Current %s is running...' % threading.current_thread().name)
    for url in urls:
        print('%s --->>> %s' % (threading.current_thread().name,url))
        time.sleep(random.random())
    print('%s ended.' % threading.current_thread().name)


print('%s is runnung...' % threading.current_thread().name)
t1 = threading.Thread(target=thread_run,name='Thread_1',args=(['url_1',
                            'url_2','url_3'],))
t2 = threading.Thread(target=thread_run,name='Thread_2',args=(['url_4',
                            'url_5','url_6'],))
t1.start()
t2.start()
t1.join()
t2.join()
print('%s ended.' % threading.current_thread().name)

"""
从 treading.Thread 继承创建线程类
"""
import random
import threading
import time


class myThreading(threading.Thread):
    def __init__(self,name,urls):
        threading.Thread.__init__(self,name=name) #初始化线程
        self.urls = urls

    def run(self):
        print('Current %s is running...' % threading.current_thread().name)
        for url in self.urls:
            print('%s --->>> %s' % (threading.current_thread().name,url))
            time.sleep(random.random())
        print('%s ended.' % threading.current_thread().name,url)


print('%s is running...' % threading.current_thread().name)
t1 = myThreading(name='Tread_1',urls=['url_1','url_2','url_3'])
t2 = myThreading(name='Tread_2',urls=['url_4','url_5','url_6'])
t1.start()
t2.start()
t1.join()
t2.join()
print('%s ended.' % threading.current_thread().name)