René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Coverage.py test suite failure since commit 0749244d134","articleBody":"# Bug report\n\n### Bug description:\n\nCoverage.py runs its test suite against nightly builds of Python.  The tests stalled last night.  Running them locally, there's one test that freezes the suite.  The GitHub action is eventually cancelled by timing out after six hours: https://github.com/nedbat/coveragepy/actions/runs/8000886484\n\nBisecting CPython, the first bad commit is 0749244d13412d7cb5b53d834f586f2198f5b9a6\n\n```\ncommit 0749244d13412d7cb5b53d834f586f2198f5b9a6\nAuthor: Brett Simmers \u003cswtaarrs@users.noreply.github.com\u003e\nDate:   Tue Feb 20 06:57:48 2024 -0800\n\n    gh-112175: Add `eval_breaker` to `PyThreadState` (#115194)\n\n    This change adds an `eval_breaker` field to `PyThreadState`. The primary\n    motivation is for performance in free-threaded builds: with thread-local eval\n    breakers, we can stop a specific thread (e.g., for an async exception) without\n    interrupting other threads.\n\n    The source of truth for the global instrumentation version is stored in the\n    `instrumentation_version` field in PyInterpreterState. Threads usually read the\n    version from their local `eval_breaker`, where it continues to be colocated\n    with the eval breaker bits.\n```\nI'm still investigating, but I'm hoping that someone familiar with the change (@swtaarrs?) will be able to help.\n\nTo reproduce:\n```\n% git clone https://github.com/nedbat/coveragepy\n% cd coveragepy\n% export COVERAGE_ANYPY=/path/to/your/python3\n% pip install tox\n% tox -qre anypy -- -n 0 -vvv -k test_multiprocessing_simple\n=== CPython 3.13.0a4+ (rev 0749244d13) with C tracer (.tox/anypy/bin/python) ===\n===================================================================== test session starts ======================================================================\nplatform darwin -- Python 3.13.0a4+, pytest-8.0.1, pluggy-1.4.0 -- /Users/ned/coverage/trunk/.tox/anypy/bin/python\ncachedir: .tox/anypy/.pytest_cache\nhypothesis profile 'default' -\u003e database=DirectoryBasedExampleDatabase(PosixPath('/Users/ned/coverage/trunk/.hypothesis/examples'))\nrootdir: /Users/ned/coverage/trunk\nconfigfile: pyproject.toml\nplugins: flaky-3.7.0, xdist-3.5.0, hypothesis-6.98.9\ncollected 1386 items / 1384 deselected / 2 selected\nrun-last-failure: no previously failed tests, not deselecting items.\n\ntests/test_concurrency.py::MultiprocessingTest::test_multiprocessing_simple[fork] PASSED                                                                 [ 50%]\ntests/test_concurrency.py::MultiprocessingTest::test_multiprocessing_simple[spawn] PASSED                                                                [100%]\n\n============================================================== 2 passed, 1384 deselected in 3.37s ==============================================================\n=== CPython 3.13.0a4+ (rev 0749244d13) with sys.monitoring (.tox/anypy/bin/python) ===\n===================================================================== test session starts ======================================================================\nplatform darwin -- Python 3.13.0a4+, pytest-8.0.1, pluggy-1.4.0 -- /Users/ned/coverage/trunk/.tox/anypy/bin/python\ncachedir: .tox/anypy/.pytest_cache\nhypothesis profile 'default' -\u003e database=DirectoryBasedExampleDatabase(PosixPath('/Users/ned/coverage/trunk/.hypothesis/examples'))\nrootdir: /Users/ned/coverage/trunk\nconfigfile: pyproject.toml\nplugins: flaky-3.7.0, xdist-3.5.0, hypothesis-6.98.9\ncollected 1386 items / 1384 deselected / 2 selected\nrun-last-failure: no previously failed tests, not deselecting items.\n\ntests/test_concurrency.py::MultiprocessingTest::test_multiprocessing_simple[fork] PASSED                                                                 [ 50%]\ntests/test_concurrency.py::MultiprocessingTest::test_multiprocessing_simple[spawn]\n```\nand there it is stuck.\n\n### CPython versions tested on:\n\nCPython main branch\n\n### Operating systems tested on:\n\nLinux, macOS\n\n\u003c!-- gh-linked-prs --\u003e\n### Linked PRs\n* gh-115856\n\u003c!-- /gh-linked-prs --\u003e\n","author":{"url":"https://github.com/nedbat","@type":"Person","name":"nedbat"},"datePublished":"2024-02-22T18:45:02.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/115832/cpython/issues/115832"}