https://github.com/apache/airflow/pull/12139 added some new params to the scheduler -- we have "cursory" docs for them in the comments in the config file, but we should have a more details docs in the scheduler.rst page.
airflow/jobs/scheduler_job.py
guard.commit()
                
            dag_runs = DagRun.next_dagruns_to_examine(session)
            
            
            
            
            
            
            
            #
            
            
            
            
            
            active_runs_by_dag_id = defaultdict(set)
            query = (
                session.query(
                    TI.dag_id,
                    TI.execution_date,
                )
                .filter(
                    TI.dag_id.in_(list({dag_run.dag_id for dag_run in dag_runs})),
                    TI.state.notin_(list(State.finished)),
                )
                .group_by(TI.dag_id, TI.execution_date)
            )
            for dag_id, execution_date in query: