This sounds like a sensible solution. If Facebook wants to start using non-UTC time coordination, like TAI, they by all means should try it. They only need to p

This sounds like a sensible solution. If Facebook wants to start using non-UTC time coordination, like TAI, they by all means should try it. They only need to publish their own NTP servers I guess, but that shouldn't be a big problem for an organization of their size. As far as I can tell, TAI will always be offset from UTC by an integer amount of full seconds, and I guess time coordination between large independent systems is mostly useful just when comparing log timestamps (I would guess almost all sensible software uses already account for much larger clock drifts than the current leap second count of 37, right?) After adopting TAI, Facebook engineers just need to remember that their log timestamps are offset by N seconds from all the others.