Computers Have a Love/Hate Relationship With the Leap Second

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Every once in a while, the folks you control the Coordinated Universal Time (UTC) system decide for the sake of accuracy to add a “leap second” to the end of a month. This brings human time into a closer congruity with solar time Our next leap second is set to occur at the end of June. Here’s how the clocks will look over a three second span:

30 June 2015 23:59:59 UTC

30 June 2015 23:59:60 UTC

01 July 2015 00:00:00 UTC

While the inserted second may enthuse astronomers and train conductors, it’s not always a good thing for computers and the people who build them. Robert McMillan at WIRED writes that the leap second from 2012 crashed sites like Reddit and caused hiccups for plane departures in Australia. The reasons vary but can usually be tied to the fact that the timekeeping systems for these sites were pegged to GPS or designed so that a day equals exactly 86,400 seconds. When the rest of the world starts meddling with phantom seconds here and there, it can really toss a wrench into the machine.

McMillan’s piece features a short interview with Linus Torvalds, the creator of Linux, who says the leap second doesn’t bother him too much. He says the problems from 2012 have all likely been patched by now and that worrying too much about the idiosyncrasies of time vis-à-vis computers is liable to cause more headaches than you could expect to solve. It’s an interesting conversation and one definitely worth reading. Check out the link below and let us now what you think.