G+: December 31st will have an extra second this …

David Coles
December 31st will have an extra second this year. I wonder how much confusion the :60 will cause.

Turns out that computers aren't great with handling extra seconds, so most large tech companies (Google, Amazon, Microsoft) have taken the approach of smearing away the difference so they can pretend the extra second doesn't exist. This is implemented by slowing down their clocks around the actual leap second so that after ~1 day this smeared time and actual time end up being the same.

Sadly there's a few competing proposals for what is the right way to do this (how long should you smear, when should you start, should it be linear or a smoother curve) but it looks like the industry is moving towards 24-hour linear smear from noon to noon UTC.

Leap Smear | Public NTP | Google Developers


(+1's) 2
David Coles
I guess it's only a problem if you're in London since the leap second occurs 2016-12-31 11:59:60 UTC.

Abe Hassan
I really wish they would've added the leap second on any day other than NYE. I don't know how TV shows will handle the countdown! You can't show both the real time and the countdown!

David Coles
I'm curious how they'll handle it too. Maybe they'll chose just to hide the time or perhaps it's just easier to smear the second away Google style.

Shouldn't be a problem for us over here in the US since we'll see the leap second this afternoon at 15:59:60 PST (or 2017-01-01 10:59:60 AEDT for my rellies back home).