This gives me a lot of confidence in their crypto currency.
1) Cryptocurrency ops are so vastly different from running a social website that I can't even think of any overlap. 2) I hate Facebook as a company, but as a builder/scaler of web apps for many years, I'm continually blown away by the speed and reliability of their website. Their operations are mind-blowing. The only comparable apps (in terms of scale) are Gmail and YouTube, and Gmail is simpler in certain key areas…
It would be interesting to know more details. I bet results are sometimes incomplete, but somehow Google manages to keep the system correct enough nobody notices a sudden quality drop.
I also understood Search has some special QoS at all levels: from the network to the scheduling of jobs...