进程线程_开启

1.进程:

  优点：可以利用多核，计算密集型

  缺点：开销大，时间慢

2.线程：

  优点：开销小，时间快，IO密集型

  缺点：不可以利用多核

#开启进程方式1 
from multiprocessing import Process
import time

def work(name):
    print("target %s is running" %name)
    time.sleep(2)
    print("target %s is done" %name)
if __name__=="__main__":
    p1=Process(target=work,args=("egon",))
    p2=Process(target=work,args=("alex",))
    p1.start()#向操作系统发送请求，开启进程
    p2.start()
    print("主进程")
'''
主进程
target egon is running
target alex is running
target alex is done
target egon is done
'''

#开启进程方式1 
from multiprocessing import Process
import time

def work(name):
    print("target %s is running" %name)
    time.sleep(2)
    print("target %s is done" %name)
if __name__=="__main__":
    p1=Process(target=work,args=("egon",))
    p2=Process(target=work,args=("alex",))
    p1.start()#向操作系统发送请求，开启进程
    p2.start()
    print("主进程")
'''
主进程
target egon is running
target alex is running
target alex is done
target egon is done
'''

#开启线程方式1
from threading import Thread
import time
def work(name):
    print("target %s is running" %name)
    time.sleep(2)
    print("target %s is done" %name)
if __name__=="__main__":
    t1=Thread(target=work,args=("egon",))
    t2=Thread(target=work,args=("alex",))
    t1.start()
    t2.start()
    print("主")

'''
target egon is running
target alex is running
主
target alex is done
target egon is don
'''

#开启线程方式2
from threading import Thread
import time
class MyThread(Thread):
    def __init__(self,name):
        super().__init__()
        self.name=name
    def run(self):
        print("target %s is running" %self.name)
        time.sleep(2)
        print("target %s is done" %self.name)
if __name__=="__main__":
    t1=MyThread("egon")
    t2=MyThread("alex")
    t1.start()
    t2.start()
    print("主")

'''
target egon is running
target alex is running
主
target alex is done
target egon is done
'''