ClientSession.request will hang forever in rare cases despite using ClientTimeout.total

[jogc]

Describe the bug

Once the TCP connection to the server is successfully established and the client has sent its request it will start waiting for a response from the server using epoll_wait with a timeout value of -1 (indefinitely). If the server simply never send a response or the connectivity is lost between the client and the server for a prolonged period epoll_wait will simply never return. Using ClientTimeout.sock_read in addition to ClientTimeout.total solves the issue (makes epoll_wait be called with a timeout instead of -1) but the documentation gives the impression that ClientTimeout.total should be enough. Since the default is total=5*60 and sock_timeout=None, every HTTP request done using aiohttp is susceptible to hanging forever in rare cases unless sock_read is set specifically.

To Reproduce

Do a request while using strace on the process and look for the epoll_wait that is done right after the request headers have been sent. Example:

sendto(6, "GET /foo HTTP/1.1\r\nHost: 127"..., 133, 0, NULL, 0) = 133
epoll_wait(3, [{events=EPOLLIN, data={u32=6, u64=6}}], 2, -1) = 1

The last argument to epoll_wait is the timeout.

Expected behavior

The client should under no circumstances hang forever when a total timeout value has been set (as is the default).

Logs/tracebacks

-

Python Version

$ python --version
Python 3.11.2

aiohttp Version

$ python -m pip show aiohttp
Name: aiohttp
Version: 3.12.12
Summary: Async http client/server framework (asyncio)
Home-page: https://github.com/aio-libs/aiohttp
Author: 
Author-email: 
License: Apache-2.0
Location: /x/y/.local/python-venv/lib/python3.11/site-packages
Requires: aiohappyeyeballs, aiosignal, attrs, frozenlist, multidict, propcache, yarl
Required-by: aiohttp_socks, jsonrpc-async

multidict Version

$ python -m pip show multidict
Name: multidict
Version: 6.0.4
Summary: multidict implementation
Home-page: https://github.com/aio-libs/multidict
Author: Andrew Svetlov
Author-email: andrew.svetlov@gmail.com
License: Apache 2
Location: /x/y/.local/python-venv/lib/python3.11/site-packages
Requires: 
Required-by: aiohttp, yarl

propcache Version

$ python -m pip show propcache
Name: propcache
Version: 0.3.2
Summary: Accelerated property cache
Home-page: https://github.com/aio-libs/propcache
Author: Andrew Svetlov
Author-email: andrew.svetlov@gmail.com
License: Apache-2.0
Location: /x/y/.local/python-venv/lib/python3.11/site-packages
Requires: 
Required-by: aiohttp, yarl

yarl Version

$ python -m pip show yarl
Name: yarl
Version: 1.20.1
Summary: Yet another URL library
Home-page: https://github.com/aio-libs/yarl
Author: Andrew Svetlov
Author-email: andrew.svetlov@gmail.com
License: Apache-2.0
Location: /x/y/.local/python-venv/lib/python3.11/site-packages
Requires: idna, multidict, propcache
Required-by: aiohttp

OS

Linux

Related component

Client

Additional context

No response

Code of Conduct

• I agree to follow the aio-libs Code of Conduct

[bharat]

This issue seems to be still happening - can we reopen this issue and submit a proper fix PR or is there something I'm missing?

[Dreamsorcerer]

The reporter closed the issue themselves, so they clearly changed their mind. Feel free to open a new issue with a reproducer.

[jogc]

I can clarify that I was unable to reproduce this when using the latest version so this issue has indeed been fixed and thats why I closed it.

The reson for the initial report was me making a mistake and not using the version I thought I was using (if I remember correctly).