IOError: Stream is closed

[Anderson]

After leaving server idle for couple of minutes and than making a request, i'm getting following error. What can it be?  

Traceback (most recent call last):

      File "/home/apphome/Development/tornadotest/tornado/web.py", line 1074, in wrapper

        return method(self, *args, **kwargs)

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 107, in wrapper

        runner.run()

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 319, in run

        yielded = self.gen.throw(*exc_info)

      File "/home/apphome/Development/tornadotest/controllers/login.py", line 27, in post

        player = yield gen.Task(backend.login_player)

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 341, in run

        self.yield_point.start(self)

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 223, in start

        self.func(*self.args, **self.kwargs)

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 107, in wrapper

        runner.run()

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 319, in run

        yielded = self.gen.throw(*exc_info)

      File "/home/apphome/Development/tornadotest/auth_backends/facebook_backend.py", line 35, in login_player

        player_id = yield gen.Task(redis.get, "pfacebook:%s" % data['user_id'])

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 341, in run

        self.yield_point.start(self)

      File "/home/apphome/Development/tornadotest/tornado/gen.py", line 223, in start

        self.func(*self.args, **self.kwargs)

      File "/home/apphome/Development/tornadotest/akane/client.py", line 24, in get

        self.send_command(callback, 'GET', key)

      File "/home/apphome/Development/tornadotest/akane/client.py", line 18, in send_command

        conn.send_command(callback, *args)

      File "/home/apphome/Development/tornadotest/akane/connection.py", line 56, in send_command

        self._stream.write(command)

      File "/home/apphome/Development/tornadotest/tornado/iostream.py", line 213, in write

        self._check_closed()

      File "/home/apphome/Development/tornadotest/tornado/iostream.py", line 535, in _check_closed

        raise IOError("Stream is closed")

    IOError: Stream is closed

[Costa Farber]

I think timeout was expired. The default is connect_timeout=20.0.

[Andrey Shmigelsky]

I measured exact time and it's comes out that after being idle for 5 minutes it throws this error. The connection_timeout is set to 20.0 as you said. 

[Александр Приймак]

As far as I understand your server is connected to some kind of backend (I see redis) and connection to this backend somehow is closed after 5 minutes of inactivity.

Did I understand right?

воскресенье, 20 мая 2012 г., 17:43:44 UTC+4 пользователь Anderson написал:

[Anderson]

Yes, but the library that i use for connecting to redis don't have code that close iostream it only writes to it. Also i tried to create a "ping" method that run query to redis with cron job every minute. It doesn't help. The interesting part is, half of the queries do work till it hits some specific query. If the query wasn't valid it wouldn't work from beginning, but why it works for five minutes and than stops???? How can i debug it? What is the reason for socket switches to None in IOStream object?

[Micheál Keane]

Assuming https://github.com/FSX/akane is what you're using, it looks like it's still in development?

I haven't had any issues with tornado-redis so far.

https://github.com/leporo/tornado-redis

Washington, DC  USA
ffaris...@gmail.com

[Frank Smit]

Ah, didn't notice you're using Akane. Yes, it's still under
development and I'm focusing more on the command and reply parsing at
the moment. And going to try out various things before it's usable for
production. I haven't seen this issue yet, because the connection
doesn't live long enough to time out while testing.

Feel free to test it out and report the bugs you find at
https://github.com/FSX/akane , but don't expect things to be fixed
immediately. I'm not developing this for work or anything related to
that; not getting paid for this. It's just interesting to work on
this. I do intend to write documentation and unit tests when the API
is stabilized.

Regards,
Frank

[Andrey Shmigelsky]

Maybe it not worth to use redis asynchronously at all? Or only in situations where i need to save data without waiting for response? I tried standard py-redis and it works way faster than all of async modules. Is the async way is only better for networks with latency problems? If the ping to redis server lets say is 0.1ms, is it rational to use async calls?  

[Frank Smit]

That's a good point. I haven't tested that yet. And I guess most time
is spend in the IOLoop/IOStream and not in sending, processing and
receiving data from Redis.