python - 如何在多线程或多处理中运行脚本

Question

这个脚本需要 2 秒才能完成，但是如何在多个线程中运行它并在 50 毫秒内完成

import urllib2                                                                                                                              
from threading import  Thread                                                                                       
def btl_test(url):                                                                                                                                                                                                          
    page = urllib2.urlopen(url) 
    print page                                                                                                            


url = ["http://google.com","http://example.com","http://yahoo.com","http://linkedin.com","http://orkut.com","http://quora.com","http://facebook.com","http://myspace.com","http://gmail.com","http://nltk.org","http://cyber.com"]
for i in url:                                                                                                                        
    t = Thread(target = btl_test,args=(i,))                                                                                                           
    t.start()

如何对结果进行排序？

Answer 1

from contextlib import closing # http://stackoverflow.com/a/25968716/968442
from multiprocessing.pool import Pool

with closing(Pool(len(url))) as pool:
    pool.map(btl_test, url)

应该是方便的片段。关于顺序，您可以使用元组分配映射并相应地打印它们。

---

更新:

根据这个blog pool.map 将返回保留顺序的输出。这是在不更改顺序的情况下以 (url, html_content) 格式打印元组列表的代码

urls = ["http://google.com","http://example.com","http://yahoo.com","http://linkedin.com","http://orkut.com","http://quora.com","http://facebook.com","http://myspace.com","http://gmail.com","http://nltk.org","http://cyber.com"]

def btl_test(url):
    import urllib2
    return url, urllib2.urlopen(url).read()

from contextlib import closing # http://stackoverflow.com/a/25968716/968442
from multiprocessing.pool import Pool

with closing(Pool(len(urls))) as pool:
    result = pool.map(btl_test, urls)

print result