deferred / deferrable task are not take in account by max_active_tasks

[raphaelauv]

Apache Airflow version

2.9.2

What happened?

If you set max_active_tasks, it do not limit the number of concurrent deferred tasks.

It's possible to restrict the number of concurrent deferred tasks with a pool but I want limit the number of tasks run by a dag and keep the possibility for every task to use a specific pool ( we can only use 1 pool by task in airflow )

What you think should happen instead?

max_active_tasks should take in account the deferred task or we should create a new boolean setting

max_active_tasks_include_deferred like what was done for the pools

How to reproduce

from datetime import datetime, timezone, timedelta

from airflow.sensors.time_sensor import TimeSensorAsync
from pendulum import today
from airflow import DAG

with DAG(
        dag_id='example',
        schedule_interval='0 0 * * *',
        max_active_tasks=10,
        start_date=today("UTC").add(days=-1)):
    for i in range(100):
        TimeSensorAsync(task_id=f"a_{i}", target_time=(datetime.now(tz=timezone.utc) + timedelta(minutes=10)).time())

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct