Hi All, We are observing intermittently that Tasks get stuck in queued state and never get executed by Airflow. On debugging it we found that one of the queued dependency was not met due to which task did not move from queued to running state. So task remained in queued state. (are_dependencies_met function returned false for QUEUE_DEPS inside _check_and_change_state_before_execution)
By looking into scheduler code it seems that scheduler does not reschedule the queued state tasks due to which task never got added to executor queue again and remained stuck in queued state. There is a logic inside _check_and_change_state_before_execution function to move the task from queued to None state(which gets picked by scheduler for rescheduling) if RUN_DEPS are not met but this logic seems to be missing for QUEUE_DEPS. It seems that task should be moved to None state even if QUEUE_DEPS are not met. Any help/pointer on this would be useful. Thanks, Raman Gupta
