Heroku

Question 1

What is dyno idling?

Answer 1

Apps that have only 1 web dyno will be idled out after a period of inactivity.
The web dyno will be shut down. When a request comes in to an idled app your
web dyno will be automatically spun back up, causing a few second delay for
this first request. Subsequent requests will perform normally.

Apps that have more than 1 web dyno are never idled out. Workers dynos are
never idled out.