python 线程(创建2种方式,守护进程,锁,死锁,递归锁,GIL锁,其他方式)

###第一种
from threading import Thread
def f1(n):
    print(n)
if __name__ == ‘__main__‘:
    t1=Thread(target=f1,args=(1,))
    t1.start()
###第二种
class mythread(Thread):
    def __init__(self,name):
        super().__init__()
        self.name=name
    def run(self):
        print(‘hellow‘+self.name)
if __name__ == ‘__main__‘:
    t=mythread(‘alex‘)
    t.start()
    print(‘主线程结束‘)

import os
from  threading import Thread
def f1(n):
    print(‘1号‘,os.getpid())
    print(‘%s号‘%n)
def f2(n):
    print(‘2号‘,os.getpid())
    print(‘%s‘%n)
if __name__ == ‘__main__‘:
    t1=Thread(target=f1,args=(1,))
    t2=Thread(target=f2,args=(2,))
    t1.start()
    t2.start()
    print(‘主进程id‘,os.getpid())
############
线程ID是一样的

import os
import time
from threading import Thread
num=100
def f1(n):
    global num
    num=3
    print(‘子线程num‘,num)
if __name__ == ‘__main__‘:
    t=Thread(target=f1,args=(1,))
    t.start()
    t.join()#主进程等待子进程运行完才继续执行
    print(‘主进程的num‘,num)
###################

子线程num 3
主进程的num 3

import time
from threading import Thread
from multiprocessing import Process
def f1():
    for i in range(5):
        i=i+i
if __name__ == ‘__main__‘:
    t_s_time=time.time()
    t_list=[]
    # 查看一下20个线程执行20个任务的执行时间
    for i in range(20):
        t=Thread(target=f1,)
        t.start()
        t_list.append(t)
    [tt.join() for tt in t_list]
    t_e_time=time.time()
    t_dif_time=t_e_time-t_s_time
    # print(t_dif_time)
    #查看一个20个进程执行的任务时间
##########################################
    p_s_time=time.time()
    p_list=[]
    for i in range(20):
        p=Process(target=f1,)
        p.start()
        p_list.append(p)
    [pp for pp in p_list]
    p_e_time=time.time()
    p_dif_time=p_e_time-p_s_time
    print(‘线程执行的时间%s‘%t_dif_time)
    print(‘进程执行的时间%s‘ % p_dif_time)
###################
线程执行的时间0.003000497817993164
进程执行的时间0.2560145854949951

import time
from multiprocessing import Process
from threading import Thread,Lock
num=100
def f1(loc):
    loc.acquire()
    global num
    tmp=num
    tmp-=1
    time.sleep(0.01)#模拟
    num=tmp
    loc.release()
if __name__ == ‘__main__‘:
    t_loc=Lock()
    t_list=[]
    for i in range(10):
        t=Thread(target=f1,args=(t_loc,))
        t.start()
        t_list.append(t)
    [tt.join() for tt in t_list]
    print(‘主进程‘,num)
##############
主进程 90

import time
from threading import Thread,Lock,RLock
def f1(locA,locB):
    locA.acquire()
    print(‘f1>>1号抢到了A锁‘)
    time.sleep(1)
    locB.acquire()
    print(‘f1>>1号抢到了B锁‘)
    locB.release()
    locA.release()
def f2(locA,locB):
    locB.acquire()
    print(‘f2>>2号抢到了B锁‘)
    locA.acquire()
    time.sleep(1)
    print(‘f2>>2号抢到了A锁‘)
    locA.release()
    locB.release()
if __name__ == ‘__main__‘:
    locA = Lock()
    locB = Lock()
    t1 = Thread(target=f1,args=(locA,locB))
    t2 = Thread(target=f2,args=(locA,locB))
    t1.start()
    t2.start()
##################
f1>>1号抢到了A锁
f2>>2号抢到了B锁