异步爬虫（基础）

#使用单线程串行方法执行
import time
def get_page(str):
time.sleep(2)
print('正在下载：',str)
name=['qwe','est','sdsaa','g56']
start_time=time.time()
for i in range(len(name)):
get_page(name[i])
end_time=time.time()
print('%d second'%(end_time))

 

 

import time
from multiprocessing.dummy import Pool
start_time=time.time()
def get_p(url):
print('zhengzai xiazai :',url)
time.sleep(2)
print('haole')
name=['a','f','v','g']
#实例化一个线程池对象
pool=Pool(4)
pool.map(get_p,name)
end=time.time()
print(end)