How much CPU is actually required to keep something like connectivitycheck-gstatic.com working at low latency for billions of devices?

Background: connectivitycheck-gstatic.com is Android's and Chrome's "is the internet reachable" URL, whenever you turn on Wifi/Mobile or open Google's browser it automatically checks the URL to see if you got a internet connection.

Purely inquisitive question, I assume gstatic-conncheck's job is not much more than a few ICMP roundtrip packets, so pretty much one of the most simple requests that your networking device can do, it's got me wondering how much CPU grunt do you need to do something so simple but at the massive scale of the requests it needs to work with (Android devices, Chrome and some other browsers, and probably more)