June 30 ‘Leap Second’ May Cause Computer Problems

Instead of the standard 86,400 seconds, June 30, 2015 will last for 86,401 seconds. An extra second isn’t enough time to catch up on your favorite TV shows or get that much-needed sleep your body has been craving, but it may have a direct impact on computer systems – and not in a good way. Information Technology experts say this extra second, known as a leap second, may wreck havoc on computer systems and infrastructures.

The International Earth Rotation Service (IERS) announced plans earlier this month to add an extra second to the atomic clock on June 30, 2015. A spokesperson for the IERS explained the need for this adjustment, citing the Earth’s natural spin. Although you can’t see or feel it, the Earth’s spin is slowing down, at a rate of approximately two thousandths of a second per day. To account for this slowdown, atomic clocks must be adjusted every so often, with June 30, 2015 being the official date for the latest atomic clock adjustment.

Some people may turn their heads at the thought of a leap second causing any real problems with computer systems. After all, the whole Y2K didn’t exactly cause any catastrophic issues as predicted. If you go back to the last leap second, though, you’ll see that it did in fact take down some major websites and services, including Mozilla, Reddit, Foursquare, LinkedIn, Yelp and StumbleUpon. Granted, they were soon fixed, but it serves as a reminder to the impact a single extra second can have on computer systems.

Being the tech-savvy company that it is, Google designed a software update to protect its search engine and related computer systems from the 2012 leap second. Rightfully known as “leap smear,” this update modified Google’s servers so they automatically added micro-seconds throughout the year. And by the time the leap second was added, the severs were already caught up. Google has yet to announce whether or not it plans to use leap smear this year, but it’s safe to assume the Mountain View company has some type of plan in place.

“You can think of the whole mess as a kind of cosmic struggle between machines, which consider a day to be 86,400 seconds, and humans, who think of a day as one spin of Planet Earth. For thousands of years, one rotation of the earth was indeed the best way of measuring 86,400 seconds, but it turns out this is an imperfect method,” wrote Wired magazine in an article describing the upcoming leap second and its ramifications.