GPS satellites use atomic clocks which don't drift aka don't become 0.1% slower or faster than they should be. OK, technically they drift, but not enough to be

GPS satellites use atomic clocks which don't drift aka don't become 0.1% slower or faster than they should be. OK, technically they drift, but not enough to be noticeable by anyone. They're the standard to which other clocks are compared. According to https://en.wikipedia.org/wiki/Atomic_clock#Evaluated_accuracy https://en.wikipedia.org/wiki/Atomic_clock#Evaluated_accurac... existing atomic clocks can drift by 1 second in 100 million or 150 million years. You won't notice that in your high-speed datacenter applications over the course of a few decades. (unless perhaps if one is plain broken, and it's noticed by comparing to the others and taken out of service)