python / python/cpython

Timeout is doubled - socket.create_connection()

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stdlib topic-socket type-bug
Dominant language
Python
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Description

Bug report

Bug description:
import socket
import time
start = time.time()
sock = socket.create_connection(
    address=("foobar", 10000),
    timeout=5)
print(time.time() - start)

No matter what value you specify as a timeout, the timeout is always doubled. If you specify 5 seconds, an exception will only be thrown after 10 seconds; if you specify 10 seconds, then only after 20.

Tested on Debian 12 with Python 3.11.

CPython versions tested on:

3.11

Operating systems tested on:

Linux

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First steps

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  4. Open a pull request that references the issue number.

Research direction

Start at the socket.create_connection() entry point and reproduce the supplied script on Linux with Python 3.11, measuring the elapsed time for several timeout values. Trace the timeout handling and identify the relevant regression-test location. Done means the observed timeout matches the requested value and the behavior is covered by a test.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
networking
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
42/100

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