Several popular Internet services including LinkedIn, Reddit and Quantas airline's reservation system and others crashed during the weekend due to an extra second added to the official timekeeping record even as system providers had warned of its effects on the internet sites.

Experts say that mostly systems based on un-patched Linux OS kernels, Hadoop instances, Cassandra databases and Java-based programs faced downtime due to the extra second. The concept of leap seconds was introduced in 1971 as a way to synchronize Coordinated Universal Time (UTC) and mean solar time.

The whole process is overseen by the International Telecommunications Union. The ITU had added a second onto the end of June 30 UTC at midnight Greenwich Mean Time, making its 25th adjustment to UTC since 1971.

Several sites with servers running Debian Linux reported downtime for servers after the leap second occurred. The servers were restored after NTP was temporarily disabled. The issue with Linux stemmed from a deadlock, a patch for which was released in March.

The ITU is now considering doing away with the leap second system to avoid problems to the IT systems around the world.