Airflow 3.1.7 - UI very slow

[romanzdk]

Hello, since upgrade to Airflow 3 we are experiencing pretty laggy UI. Sometimes we need to refresh the UI a few times so the grid loads.

We run on python 3.12.12, On-prem Kubernetes deployment, 3 replicas of the webserver, postgres 16.6 in HA.

What should we look after in order to improve the responsiveness?

[saidiraja]

Hi,

I recently worked with Airflow 3.x locally (standalone mode), and while my setup is much smaller, I also noticed that the UI can sometimes feel slow or take time to fully load certain views.

A few things that might be worth checking:

• Browser/network side: Sometimes the grid view loads multiple API calls, so delays can come from network latency or browser performance.
• Number of DAGs and tasks: A large number of DAGs or task instances can significantly impact UI responsiveness.
• Database performance: Since the UI depends heavily on metadata queries, slow responses from Postgres could affect loading times.
• Webserver logs: Checking logs might reveal slow API endpoints or timeouts.

From a usability perspective, it might also help if the UI provided clearer feedback when data is still loading or if requests are delayed.

I’d be interested to know if others running at scale have identified specific bottlenecks in Airflow 3.x UI performance.

[bbovenzi]

We had a UI-only performance update in 3.1.6 but we have more API improvements coming in 3.2.2: #64034