task.queued_duration metric not emitted in Airflow 3 (all executors)

[sakethsomaraju]

Under which category would you file this issue?

Airflow Core

Apache Airflow version

3.x

What happened and how to reproduce it?

What happened:

task.queued_duration (legacy: dag.<dag_id>.<task_id>.queued_duration) is never emitted in Airflow 3 regardless of executor (LocalExecutor, CeleryExecutor, KubernetesExecutor). The companion metric task.scheduled_duration emits correctly.

No "cannot record queued_duration" warnings appear in logs, the metric emission code is never reached, not silently skipped.

How to reproduce:

1. Run any DAG on Airflow 3 with StatsD configured
2. Observe task.scheduled_duration (or legacy dag.<dag_id>.<task_id>.scheduled_duration) appears in metrics
3. Observe task.queued_duration (or legacy dag.<dag_id>.<task_id>.queued_duration) is absent

What you think should happen instead?

task.queued_duration should be emitted each time a task transitions from QUEUED --> RUNNING, matching Airflow 2 behavior.

Operating System

linux

Deployment

None

Apache Airflow Provider(s)

No response

Versions of Apache Airflow Providers

No response

Official Helm Chart version

Not Applicable

Kubernetes Version

No response

Helm Chart configuration

No response

Docker Image customizations

No response

Anything else?

• task.scheduled_duration emits correctly because the scheduler still owns the SCHEDULED --> QUEUED transition and calls emit_state_change_metric(QUEUED) directly.
• queued_dttm is correctly set when the task enters QUEUED state , so the timing data is available, it just never gets consumed for the metric.
• This looks like a regression from Airflow 2 where queued_duration was reliably emitted for all executor types.

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

[saidiraja]

Hi, I would like to work on this issue.

I have started reproducing the problem locally on Airflow 3.2.0 and confirmed that the task.queued_duration metric is not emitted, while the timing data seems to be available.

I will investigate where the metric emission is missing and propose a fix.

Thanks!