我使用gevent进行并发下载 基于this示例,这是代码:
import gevent
from gevent import monkey
urls = ['https://www.djangoproject.com/','http://www.nytimes.com/','http://www.microsoft.com']
monkey.patch_all()
import urllib2
from datetime import datetime
def print_head(url):
print ('Starting %s' % url)
data = urllib2.urlopen(url).read()
print ('%s: %s bytes: %r' % (url, len(data), data[:50]))
startTime = datetime.now()
jobs = [gevent.spawn(print_head, url) for url in urls]
gevent.joinall(jobs)
totalTime = datetime.now() - startTime
print "Total time: %s" % totalTime
我的问题是上面的代码需要比串行版本更长的时间,并且在大多数情况下它会超时。这是更快的串行版本:
import urllib2
from datetime import datetime
urls = ['https://www.djangoproject.com/','http://www.nytimes.com/','http://www.microsoft.com']
def print_head(url):
print ('Starting %s' % url)
data = urllib2.urlopen(url).read()
print ('%s: %s bytes: %r' % (url, len(data), data[:50]))
startTime = datetime.now()
for url in urls:
try:
print_head(url)
except:
print 'ops EXCEPTION :('
totalTime = datetime.now() - startTime
print "Total time: %s" % totalTime