python-----多线程、线程池、进程池

import  threading
import time

###############################多线程###############################
#----------函数无参数，子线程等待方式 循环join
def run():
   time.sleep(2)
   print("正在执行" ,threading.current_thread())
starttime=time.time()
threads=[]
for i in range(3):
   t=threading.Thread(target=run)
   threads.append(t)
   t.start()
for t in threads:
   t.join()
endtime=time.time()
print(endtime-starttime)


#----------函数无参数，子线程等待方式 循环join函数带参数run(name) 线程传递参数args=('ABC',) 一个参数元组必须用“，”，子线程等待方式 while threading.active_count() != 1
def run(name):
   time.sleep(2)
   print("正在执行：%s" %name,threading.current_thread())
starttime=time.time()

for i in range(3):
   t=threading.Thread(target=run,args=('ABC',))
   t.start()
while threading.active_count() !=1:
   print("子线程已执行完毕")
endtime = time.time()
print(endtime - starttime)

################################线程池###############################
import threadpool
#辅助方法
import pymongo,requests
client = pymongo.MongoClient(host='118.24.3.40',port=27017)
table = client['likun']['qq_group_likun']
all_qq = [i.get('qq') for i in table.find()]
url = 'http://q4.qlogo.cn/g?b=qq&nk=%s&s=140'

def down_img(qq_num):
   res = requests.get(url%qq_num).content
   with open('%s.jpg'%qq_num,'wb') as fw:
      fw.write(res)

#线程池实现
pool = threadpool.ThreadPool(200)  #线程池的大小
all_requests = threadpool.makeRequests(down_img,all_qq)#分配数据 makeRequests(函数,list)
for r in all_requests:
   pool.putRequest(r)   #发请求
pool.wait()#等待所有线程运行完
print('done！下载完成。')



#################################进程池###############################
from multiprocessing import Process,Pool,active_children
import pymongo,requests
import threading
#辅助方法
client = pymongo.MongoClient(host='118.24.3.40',port=27017)
table = client['likun']['qq_group_likun']
all_qq = [i.get('qq') for i in table.find()]
url = 'http://q4.qlogo.cn/g?b=qq&nk=%s&s=140'
def down_img(qq_num):

   res = requests.get(url%qq_num).content
   with open('%s.jpg'%qq_num,'wb') as fw:
      fw.write(res)
#进程池实现
if __name__ == '__main__':
   # for qq in all_qq:
   #  p = Process(target=down_img,args=(qq,)) #启动多进程
   #  p.start()
   pool = Pool(5)#指定进程池的大小
   list(pool.map(down_img,all_qq)) #运行 使用进程池