2015迎来闰秒：全球计算机陷入恐慌

The year 2015 will have an extra second — which could wreak havoc on the infrastructure powering the internet.

2015年将会多一秒钟——这会对网络基础设施造成严重破坏。

At 11.59 on June 30, clocks will count up all the way to 60 seconds. That will allow the Earth’s spin to catch up with atomic time.

6月30日11点59分，时钟会一直走到60秒，那会使得地球自转赶上原子时间。

The Earth’s spin is gradually slowing down, by about two thousandths of a second per day, but atomic clocks are constant. That means that occasionally years have to be lengthened slightly, to allow the slowing Earth to catch up with the constant clock.

地球自转逐步减速，每天减少2/1000秒，但是原子钟是不变的。那意味着偶尔有年份会稍稍长一些，来减缓地球赶上恒速计时器。

But last time it happened, in 2012, it took down much of the internet. Reddit, Foursquare, Yelp and LinkedIn all reported problems, and so did the Linux operating system and programmes using Java.

但是上一次闰秒是发生在2012年，冲击了一大片互联网。Reddit，Foursquare，Yelp还有LinkedIn（领英），还有Linux操作系统和使用Java的程序都报错了。

The reset has happened 25 times since they were introduced in 1972, but the computer problems are getting more serious as increasing numbers of computers sync up with atomic clocks. Those computers and servers are then shown the same second twice in a row — throwing them into a panic.

自从1972年引进闰秒这个概念以来，重置发生了25次，但是随着电脑（和原子钟同步）数量的增长，电脑的问题变得越来越严重。那些电脑和服务器随后连续显示相同的两秒钟——而引起了恐慌。

If a computer is told to do an operation at the time that is repeated, for instance, the computer is unsure what to do. Or if an email is received in that moment, it could find its way in the wrong bit of the server.

举个例子，如果一台电脑当时接到的操作命令操作重复了，电脑就不确定该怎么做了。或者如果那时收到了一封邮件，服务器就会发现报错了。

Last time, Google anticipated the problem and built a smart update, which it called “leap smear”.  It modified its servers so that they would add a little bit of extra time every time they were updated, so that by the time of the leap second they were already caught up with the new time. It said when it laid out the plan in 2011 that it would use the same technique in the future, when new leap seconds are announced.

上一次，谷歌预料到了这个问题，并巧妙搭建了更新，称作“leap smear”。它更改服务器使得每回在更新时都会增加一点额外的时间，如此到闰秒的时候，他们已经赶上了新时间。它说当2011年出台了这个方案时，新闰秒到来之际的未来也能用到同样的技术。

Leap seconds were initially added at least once a year, but have slowed since 1979. The US wants to get rid of them entirely, arguing that they cause too much disruption, but others have opposed the change.

闰秒起先一年至少增加一次，但是自从1979年来就放慢了。美国希望彻彻底底摆脱它们，并声称它们引起了太多破坏，但是其他人反对此改变。

Britain, for example, has said that the leap second should stay. Getting rid of it would mean the end of Greenwich Mean Time, which is measured by the sun and would no longer be accurate.

举个例子，英国就表示闰秒应该保留。摆脱了闰秒就意味着由太阳测出的格林威治标准时间的消亡，GMT也不再精准了。