René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Running tests in parallel on Windows quits too soon","articleBody":"On my Win10 the test suite completes when run serially.  But with main and 3.11, but not 3.10, it quits too soon with -j0.  This has occured with both repository debug builds and installed 3.11.0b4.  Failure is currently deterministic with variable details.  Presence of -ugui or -uall has no apparent effect.\r\n\r\nWhat happens is that roughly about 100 tests before the end, a 'regrtest worker thread' fails ('warning') with `UnicodeDecodeError: 'utf-8' codec can't decode byte 0x91 in position \u003cvariable\u003e: invalid start byte`.  The 14 worker processes are stopped and the usual summary is given, but with an additional list of '\u003cn\u003e tests omitted \u003clist of test names'.  The test is called a 'SUCCESS'.  This is followed by a traceback for SystemExit(0), followed by 1 or more tracebacks for PermissionError because a temporary test file is supposedly used by another process.\r\n\r\nAttaching a file with output starting with the initial warning fails.  Will paste separately.\r\n\r\nIf this is not limited to my system, I think it should be a release blocker.\r\n","author":{"url":"https://github.com/terryjreedy","@type":"Person","name":"terryjreedy"},"datePublished":"2022-07-19T22:44:10.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":34},"url":"https://github.com/95027/cpython/issues/95027"}