python / python/cpython

contextvars.Context.run hangs forever in ProccessPoolExecutor

Open
#83,438 2 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

3.8 (EOL) topic-multiprocessing type-bug
Dominant language
Python
Stars
77.2k
Forks
36k
PR merge metrics
PR metrics pending

Description

BPO 39257
Nosy @1st1, @Ronserruya

Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.

Show more details

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-01-08.10:34:34.026>
labels = ['type-bug', '3.8']
title = 'contextvars.Context.run hangs forever in ProccessPoolExecutor'
updated_at = <Date 2020-01-10.19:23:50.063>
user = 'https://github.com/Ronserruya'

bugs.python.org fields:

activity = <Date 2020-01-10.19:23:50.063>
actor = 'yselivanov'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = []
creation = <Date 2020-01-08.10:34:34.026>
creator = 'ronserruya'
dependencies = []
files = []
hgrepos = []
issue_num = 39257
keywords = []
message_count = 2.0
messages = ['359575', '359749']
nosy_count = 2.0
nosy_names = ['yselivanov', 'ronserruya']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue39257'
versions = ['Python 3.8']

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the linked BPO issue 39257 and the reported interaction between contextvars.Context.run and ProcessPoolExecutor. The payload names no source files or tests, so first reproduce the hang and identify the relevant implementation and regression coverage. Done means Context.run no longer hangs in this executor scenario.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
backend
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.