Everybody always talks about needing more time. Well, this year you get it! Saturday night will be one second longer than normal. A leap second is being inserted in order to slow clocks down to match the Earth’s rotation.
Beyond just adding a second to your day, your software needs to be ready as well. The addition of leap seconds in 2012 and 2015 means that many software systems are ready for it. This includes CycleCloud and the cloud service providers it works with.
Leap second handling
Here’s how the cloud service providers handle the leap second:
- Amazon Web Services — The additional second is spread over the 24 hour period from 12:00 UTC on December 31 through 12:00 UTC on January 1. Each “second” will be 1/86400 longer.
- Azure — In 2015, Azure inserted leap seconds at midnight local time. The assumption is that they will do this again.
- Google Cloud — The additional second is spread over the 20 hour period from 14:00 UTC on December 31 through 10:00 UTC on January 1.
Instances started in the cloud providers will depend on the configured behavior. Generally speaking, Linux instances will use the NTP server pools and handle the change in the kernel. Windows instances on AWS will follow the AWS time adjustment above. Windows generally handles leap seconds by changing the clock at the next update.
It’s a leap year, too
In case one extra second was not enough 2016 for you, remember that this year was a leap year as well. If your application considers the day of the year, you’ll want to make sure it’s ready for a 366th day. For more information about handling leap years, see Microsoft’s blog post.
And be sure to enjoy your extra time!