An (possibly) apocryphal story at Google is that when Gmail first launched, they figured that email delivery isn't latency-sensitive, so they purposefully set u

An (possibly) apocryphal story at Google is that when Gmail first launched, they figured that email delivery isn't latency-sensitive, so they purposefully set up compute-intensive jobs (like spam analysis) to be cross continent. When it's night time in the U.S. people aren't doing a lot of web searches, so U.S. servers are relatively idle and the entire world's email delivery processing happens in the U.S.; when the U.S. wakes up all those email processing gets done in Europe. My takeaway is that for large companies cost of international bandwidth isn't such a big factor, at least relative to compute.