Hosted on Render.com with a simple ‘hello world’ application we see messages exactly every 20 minutes of this form:
2025-06-12 11:47:20.271 Session with id 9f8ea2af-1b41-40d2-bfde-383b55153414 is already connected! Connecting to a new session.
This is the case in (at least) 1.37.1, 1.44.0 and 1.45.1
In versions >1.38 disconnectedSessionTTL is set to 1 hour or more.
The handover to each new 20 minute session is seamless - not problematic - but we are trying to understand why this is happening.
Render assert that on our (paid for) package they do not terminate websockets or close early except on very occasional proxy node maintenance.
Is Streamlit closing websockets early?