Python并发执行（未完待续）

python的多进程执行

多进程实现方式一

from multiprocessing import Processdef func1(name):print("测试 %s 多进程" %name)if __name__ == "__main__":process_list = []for i in range(5):p = Process(target = func1, args = ('Python', ))p.start()process_list.append(p)for i in process_list:p.join()print("结束测试")

多进程实现方式二 

from multiprocessing import Processclass MyProcess(Process):   # 继承Process类def __init__(self, name):super(MyProcess, self).__init__()self.name = namedef run(self):print("测试%s多进程" % self.name)if __name__ == '__main__':process_list = []for i in range(5):p = MyProcess('Python {}'.format(i))p.start()process_list.append(p)for i in process_list:p.join()print('测试结束')

python进程通信方式

管道Pipe

调用Pipe()返回管道两端的Connection；Pipe的读写效率高于Queue，进程间的Pipe基于fork机制建立。

Python官方文档的描述：

Returns a pair (conn1, conn2) of Connection objects representing the ends of a pipe.

新建Pipe(duplex)的时候

• 如何duplex为Flase，Pipe适用于只有两个进程一读一写的单双工情况； 
• 如果duplex为True，Pipe适用于两个进程双工情况；【默认为True】

Pipe的方法包含 send()、recv()、close()；当pipe的输入端被关闭，且无法接受接收到输入端的值，则会抛出EOFError。

from multiprocessing import Process, Pipe
import timedef func1(conn):print("子进程发送消息：")conn.send("你好主进程")print("子进程接收消息：")print(conn.recv())conn.close()if __name__ == '__main__':conn1, conn2 = Pipe()p = Process(target = func1, args = (conn2, ))p.start()time.sleep(1)print('主进程接受消息：')print(conn1.recv())print('主进程发送消息：')conn1.send("你好子进程")p.join()print('结束测试')

 进程队列

Queue是基于Pipe实现的

Queue的使用主要是一边put()，一边get()；但是Queue可以是多个Process进行put操作，也可以是多个Process进行get操作。

from multiprocessing import Process, Queue
import timedef func1(queue, index):print("子进程 {} 开始put数据".format(index))queue.put("子进程 {}, 通过Queue开始通信".format(index))if __name__ == "__main__":queue = Queue()process_list = []for i in range(3):p = Process(target = func1, args = (queue, i, ))p.start()process_list.append(p)print("开始join")for i in process_list:p.join()print('主进程获取Queue数据')for i in range(3):print(queue.get())print("结束测试")

python的多线程执行

from concurrent.futures import ThreadPoolExecutor
import time# 设置最大的线程个数
executor = ThreadPoolExecutor(max_workers = 8)
all_num = 100def worker(index):time.sleep( (int)(index) / 5)print(index)def run():time1 = time.time()for id_ in range(all_num):executor.submit(worker,id_)executor.shutdown(wait = True)time2 = time.time()print(time2 - time1)if __name__ == "__main__":run()