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Fatal Python error: could not acquire lock at interpreter shutdown...

See original GitHub issue

A little bit excited about this project :)

In the process playing around, and have been getting some odd results with the following program:

# main.py
from chopsticks.tunnel import Tunnel
import tasks

def main(host):
    host.call(tasks.get_time)

if __name__ == '__main__':
    main(Tunnel('user@example.com'))

# tasks.py
import subprocess

def get_time():
    return subprocess.run('time', stdout=subprocess.PIPE, shell=True).stdout.decode()

Sometimes nothing prints, and program exits with code 0.

Sometimes I get the following (expected) printout (and code 0):

[user@example.com] Usage: time [-apvV] [-f format] [-o file] [--append] [--verbose]
[user@example.com]        [--portability] [--format=format] [--output=file] [--version]
[user@example.com]        [--quiet] [--help] command [arg...]

… and sometimes I get a total failure:

[user@example.com] Usage: time [-apvV] [-f format] [-o file] [--append] [--verbose]
Fatal Python error: could not acquire lock for <_io.BufferedWriter name='<stderr>'>
at interpreter shutdown, possibly due to daemon threads

Thread 0x00007f86dde4c700 (most recent call first):
  File ".../lib/python3.6/site-packages/chopsticks/ioloop.py", line 155 in println
  File ".../lib/python3.6/site-packages/chopsticks/ioloop.py", line 162 in _check
  File ".../lib/python3.6/site-packages/chopsticks/ioloop.py", line 145 in on_data
  File ".../lib/python3.6/site-packages/chopsticks/ioloop.py", line 223 in step
  File ".../lib/python3.6/site-packages/chopsticks/ioloop.py", line 242 in run
  File "/usr/lib64/python3.6/threading.py", line 864 in run
  File "/usr/lib64/python3.6/threading.py", line 916 in _bootstrap_inner
  File "/usr/lib64/python3.6/threading.py", line 884 in _bootstrap

Current thread 0x00007f86e259c4c0 (most recent call first):
[1]    6661 abort (core dumped)  ./main.py

The number of lines that successfully print before failure varies.

I’m running Python 3.6.1 locally, and 3.5.2 on the server. I don’t know if it helps, but the result of running ssh -V is OpenSSH_7.5p1, OpenSSL 1.1.0f 25 May 2017.

Please let me know if there’s any further information I could provide to help shed some light on this.

Issue Analytics

State:
Created 6 years ago
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

lordmauvecommented, Jul 2, 2017

Thanks. I’ll open an issue about the stderr handling specifically.

0reactions

meshycommented, Jul 2, 2017

I’ve just had another look. I was indeed using chopsticks 0.5, and it works on master \o/.

I’ve done a bisect, and it looks as though it was fixed in 41d7683da300e2a0f88a3a46add0eb49b3f54fce.

Thank you!

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