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= tornado并发加到2000就开始出错?! =


##startInc
== 现象 ==
{{{
dean forever deanforwever2010@gmail.com
发件人当地时间:	 发送时间 10:47 (GMT+08:00)。发送地当前时间：下午10:05。 ✆
主题:	 [CPyUG] 测试tornado性能时 并发加到2000就开始出错？
}}}
双核 2.0Ghz debian系统
跑tornado的hello world：

{{{
#!python
import tornado.httpserver
import tornado.ioloop
import tornado.web
class MainHandler(tornado.web.RequestHandler):
   def get(self):
       self.write("Hello, world")
application = tornado.web.Application([(r"/", MainHandler),])

if __name__ == "__main__":
   http_server = tornado.httpserver.HTTPServer(application)
   http_server.listen(1081)
   tornado.ioloop.IOLoop.instance().start()

}}}

`ab -n 10000 -c 1000 http://192.168.8.2:8889/`  并发可达到1588req/s

执行 `ab -n 10000 -c 2000 http://192.168.8.2:1081/`
出错:
{{{
Traceback (most recent call last):
 File "/usr/local/lib/python2.6/site-packages/tornado-1.2.1-py2.6.egg/tornado/ioloop.py",
line 269, in start
 File "/usr/local/lib/python2.6/site-packages/tornado-1.2.1-py2.6.egg/tornado/stack_context.py",
line 173, in wrapped
 File "/usr/local/lib/python2.6/site-packages/tornado-1.2.1-py2.6.egg/tornado/httpserver.py",
line 238, in _handle_events
 File "/usr/local/lib/python2.6/socket.py", line 195, in accept
error: [Errno 24] Too many open files
}}}

在另一台8核 8G内存服务器上跑ab 性能也没有见提升，并发开到2000也出错：
{{{
Traceback (most recent call last):
 File "/usr/local/python/lib/python2.6/site-packages/tornado-2.1.1-py2.6.egg/tornado/ioloop.py",
line 309, in start
 File "/usr/local/python/lib/python2.6/site-packages/tornado-2.1.1-py2.6.egg/tornado/netutil.py",
line 314, in accept_handler
 File "/usr/local/python/lib/python2.6/socket.py", line 195, in accept
error: [Errno 24] Too many open files

}}}


求指点，是否我的测试方法哪里不对，怎么看不到别的大牛写的 3000+的并发效果？
=== 内置支持 ===
{{{
WooParadog guohaochuan@gmail.com
发件人当地时间:	 发送时间 20:20 (GMT+08:00)。发送地当前时间：下午10:08。 ✆
}}}

翻了一下, 发现tornado自带了并行的东西...用法如下..在我的机器上(Dell i5/4G)能跑到5790.15 [#/sec] (mean)
不用的话在2726.08 [#/sec] (mean).. 嗯, 笔记本假四核...

{{{
#!python
#!/usr/bin/env python
# -*- coding: utf-8 -*-
'''
tor.py
Author: WooParadog
Email:  Guohaochuan@gmail.com

Created on
2011-11-25
'''

import tornado
import tornado.process
import tornado.web
from tornado import httpserver
from tornado import ioloop
from tornado.web import RequestHandler

class non(RequestHandler):
    def get(self):
        """docstring for get"""
        self.write("hello")
        
def main():
    """docstring for main"""
    sokets = tornado.netutil.bind_sockets(8080)
    tornado.process.fork_processes(0)
    application = tornado.web.Application([
        ('',non)])
    http_server = httpserver.HTTPServer(application)
    http_server.add_sockets(sokets)
    ioloop.IOLoop.instance().start()

if __name__ == '__main__':
    main()
}}}

哇哇 大牛你这个最管用了！
{{{
ab -n 10000 -c 1000 http://192.168.0.36:1081/ 
...
Requests per second: 8416.98 [#/sec] (mean)

}}}
并发开到5000 都还能达到 5000req/s
看来真是自己用的不对 呵呵

=== 飞龙分析 ===
{{{
Felinx Lee felinx.lee@gmail.com
发件人当地时间:	 发送时间 11:33 (GMT+08:00)。发送地当前时间：下午10:10。 ✆

}}}

 * 这个是系统允许的fd限制所制，可以参考下这个
    * http://thedaneshproject.com/posts/how-to-increase-total-file-descriptors-count-on-linux/
 * 每个进程的fd limit有限制，参考下：
    * http://stackoverflow.com/questions/2569620/socket-accept-error-24-to-many-open-files
 * 用了fork其实是根据多核来跑多个进程，每个进程的限制还没有达到，所以没出错。但tornado的老大们是不推荐用fork的。
 
##endInc

----
'''反馈'''

创建 by -- ZoomQuiet [<<DateTime(2011-11-25T22:11:35+0800)>>]