Airflow tasks get stuck at “queued” status and never gets running
I'm using Airflow v1.8.1 and run all components (worker, web, flower, scheduler) on kubernetes & Docker. I use Celery Executor with Redis and my tasks are looks like: (start) -> (do_work_for_product1) ├ -> (do_work_for_product2) ├ -> (do_work_for_product3) ├ … So the start task has multiple downstreams. And I setup concurrency related configuration as below: parallelism = 3 dag_concurrency = 3 max_active_runs = 1 Then when I run this DAG manually (not sure if it never happens on a scheduled task) , some downstreams get executed, but others stuck at "queued" status. If I clear the task from