Leap second bug wreaks havoc for major websites built on Java

2 Jul 2012

Popular websites such as Reddit and software platforms such as Mozilla have been disrupted by the addition of an extra second to the world’s atomic clocks. In particular, platforms that rely heavily on the Java software language are being disrupted.

The changing speed of the Earth’s rotation means an adjustment had to be made by the International Earth Rotation and Reference Systems Service. Around 25 leap seconds have been made since 1972.

News sharing site Reddit was knocked offline by the change that was made on Saturday evening (30 June) because of the effect the extra second had on its open-source database, Apache Cassandra, built on Java.

Firefox creator Mozilla was experiencing similar problems with its Hadoop platform, which was also built using Java.

Mozilla engineer Eric Ziegenhorn wrote on the Mozilla bug report: “Servers running Java apps such as Hadoop and ElasticSearch don’t appear to be working. We believe this is related to the leap second happening tonight because it happened at midnight GMT.”

Other popular sites including Gawker, Yelp, Buzzfeed, Opera, Foursquare and LinkedIn were also affected by the bug, which choked up servers and caused predictability issues.

The bug is also reported to have affected Linux servers.

The atomic clock issue is known and understood in the industry, however, and internet companies like Google, for example, compensate and avoid disruption by adding milliseconds prior to the addition of a leap second.

Infinity time image via Shutterstock

John Kennedy is a journalist who served as editor of Silicon Republic for 17 years