waterWang opened a new pull request, #71384: URL: https://github.com/apache/airflow/pull/71384
### Problem When a DAG is paused while it has an active (running) DagRun — e.g. one started via manual trigger before the pause, or a manual trigger on an already-paused DAG that got an initial burst of tasks dispatched — the scheduler stops scheduling further task instances for that run. The run does not fail and logs no error; it simply stalls indefinitely in `running` state with remaining tasks stuck in `scheduled`, `queued_when=None`, never sent to the executor. This happens because `is_paused` is checked as a single gate that governs both "should new DagRuns be created" and "should ready task instances in existing DagRuns be scheduled." The two are conflated. ### Root cause Two places filter by `is_paused` to block task scheduling, when only DagRun creation should be blocked: 1. **`scheduler_job_runner.py`**: The task scheduling query filters out ALL task instances of paused DAGs via `.where(~DM.is_paused)`, including those belonging to already-RUNNING DagRuns. 2. **`dagrun.py` `next_dagruns_to_examine()`**: The method that selects RUNNING DagRuns for scheduling examination filters out all DagRuns of paused DAGs via `DagModel.is_paused == false()`. ### Fix - Remove `.where(~DM.is_paused)` from the task scheduling query in `scheduler_job_runner.py` - Remove `DagModel.is_paused == false()` from `next_dagruns_to_examine()` in `dagrun.py` **Preserved**: `DagModel.dags_needing_dagruns()` still filters by `is_paused == false()`, so paused DAGs cannot create **new** DagRuns. The `_update_dag_run_state_for_paused_dags` timer still runs every 60s for edge cases. The QUEUED DagRun filter in `dagrun.py` (line 818) also retains its `is_paused` check, so queued runs for paused DAGs are not promoted. ### Related issue Closes #71381 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
