What does Autotune do?
Autotune finds the right Ingress Rate for your domain by sampling the performance of your pages. Think of it as a continual load test, using live traffic to ascertain the right rate to send users from your Waiting Room to your website.
How does Autotune know how my website is performing?
Why does Autotune dial the Ingress Rate down when there is low traffic?
Autotune plays it safe by setting a rate that is commensurate with demand to your domain, and then raising the rate as the demand increases. This allows any load protection measures your website might have in place, in terms of caching or auto-scaling, to take effect, rather than being shocked by spikes in demand. As your website adapts to demand it may well be able to perform better, allowing Autotune to increase the rate.