进程实例： import threading import time def run(n): print("task",n) time.sleep(2) t1 = threading.Thread(target=run,args = ("t1",)) t2 = threading.Thread(target=run,args = ("t2",)) t1.start() t2.start() 多线程类实现方法： class MyThread(threading.Thread): def __init__(self,n): super(MyThread,self).__init__() self.n = n def run(self): print("runint task",self.n) t1 = MyThread("t1") t1.run() 一个程序有多个线程的话，子线程是并发执行的，怎么才能等等子线程结束结果呢，关健字join() import threadingimport time def run(n):
print("task ",n ) time.sleep(2) print("task done",n)start_time = time.time()
t_objs = [] #存线程实例for i in range(50): t = threading.Thread(target=run,args=("t-%s" %i ,)) t.start() t_objs.append(t) #为了不阻塞后面线程的启动，不在这里join，先放到一个列表里# for t in t_objs: #循环线程实例列表，等待所有线程执行完毕
# t.join() print("----------all threads has finished...")print("cost:",time.time() - start_time)# run("t1")# run("t2")如何做到主线程结束，子线程就结束呢，要用到守护线程 关健字 .setDaemon(True)
import threadingimport timedef run(n):
print("task ",n ) time.sleep(2) print("task done",n,threading.current_thread())start_time = time.time()
t_objs = [] #存线程实例for i in range(50): t = threading.Thread(target=run,args=("t-%s" %i ,)) t.setDaemon(True) #把当前线程设置为守护线程 t.start() t_objs.append(t) #为了不阻塞后面线程的启动，不在这里join，先放到一个列表里# for t in t_objs: #循环线程实例列表，等待所有线程执行完毕
# t.join()time.sleep(2)
print("----------all threads has finished...",threading.current_thread(),threading.active_count())print("cost:",time.time() - start_time)# run("t1")# run("t2")全局解析器锁
无论你的主机有多少个核，python的线程其实只有一个线程，一切都是假象 上下文切换。它是调用c写的原生内核接口，加锁方法，，，，python3.0以上会自动加锁，新版忽略
_author__ = "Alex Li"
import threading
import time
def run(n):
lock.acquire() global num num +=1 time.sleep(1) lock.release()lock = threading.Lock()num = 0t_objs = [] #线程实例for i in range(50): t = threading.Thread(target=run,args=("t-%s" %i ,)) t.start() t_objs.append(t) #为了不阻塞后面线程的启动，不在这里join，先放到一个列表里
for t in t_objs: #循环线程实例列表，等待所有线程执行完毕
t.join()
print("----------all threads has finished...",threading.current_thread(),threading.active_count())
print("num:",num)
线程无法发挥计算机性能，，只适用io操作，大密集CPU操作时用进程 下面一人简单的例子创造进程
from multiprocessing import Process
import time
def f(name):
time.sleep(2)
print('hello', name)
if __name__ == '__main__':
p = Process(target=f, args=('bob',))
p.start()
p.join() import multiprocessing
import time
def run(name):
time.sleep(1)
print('hello',name)
if __name__ == "__main__":
for i in range(10):
print("e")
p = multiprocessing.Process(target =run, args = ('xs',))
p.start()
p.join()
import multiprocessing import time def f(name): time.sleep(1) print('hello',name) if __name__ == "__main__": for i in range(10): print("e") p = multiprocessing.Process(target =f, args = ('xs',)) p.start() p.join() 如何在进程中加入线程例子： import multiprocessing import time,threading def thr(): print('输出当前线程',threading.get_ident()) def run(name): time.sleep(1) print('hello',name) #没有参数直接忽略，逗号结束 t = threading.Thread(target=thr,) t.start() if __name__ == "__main__": for i in range(10): p = multiprocessing.Process(target =run, args = ('xs',)) p.start() p.join() #每一个进程都是父进程启动的，，， from multiprocessing import Process import os def info(title): print(title) print('module name',__name__) print('父进程id',os.getppid()) print('自己的进程id',os.getpid()) def f(name): info('\033[31;1m dfdfdfdfdfdfd \033[0m') print("hello",name) if __name__=='__main__': info('\033[31;1m dfdfdfdfdfdfd \033[0m') p = Process(target = f,args = ('bob',)) p.start() p.join() #每一个进程都是父进程启动的，，， # 本程序的第一个父ID是pychrm 子进程是自己写的那个主函数，，而主函数调用手，子进程 变成了子进程的父进程 id from multiprocessing import Process import os def info(title): print(title) print('module name',__name__) print('父进程id',os.getppid()) print('自己的进程id',os.getpid()) def f(name): info('\033[31;1m funcif \033[0m') print("hello",name) if __name__=='__main__': info('\033[31;1m pychrmfun \033[0m') p = Process(target = f,args = ('bob',)) p.start() p.join()