Linux processing leap seconds

Leap second Introduction can refer to Wikipedia https://zh.wikipedia.org/wiki/leap seconds

Linux processing leap seconds

Linux uses a UTC clock, and time synchronization is performed through NTP, which sends a leap-second event notification to the most edge of the NTP server at the first level, and then NTP notifies the client's operating system of the leap second. Leap-seconds notifications are handled by the operating system.

A leap second affects the Linux operating system that partially opens the NTP service--which causes the Linux kernel to crash! Linux kernel resolves this issue in the post-2.6.18-164.E15 version.

How does our operating system handle positive leap seconds notifications? Typically there are three implementations:

1. Back one second.
2. Stop for one second.
3. Real increase of one second.

The first two approaches solve this problem in a workaround or hack way. The first approach causes some timestamp-based message notification to be ordered, and the second causes two identical timestamp to appear. Finally, there is no timestamp problem.

Linux processing leap seconds