leap second outage

Wed Jul 1 05:38:49 UTC 2015

On Wed, 1 Jul 2015, Jean-Francois Mezei wrote:

> However, in systems that expect tightly synchronized clocks, they would 
> want all the nodes to make the NTP adjustement at the same time.

This is both an operating system and application problem.

http://infiniteundo.com/post/25326999628/falsehoods-programmers-believe-about-time
http://infiniteundo.com/post/25509354022/more-falsehoods-programmers-believe-about-time

This is similar to the jiffycounter wrapping, since this doesn't happen 
that often, it's not commonly tested for. Good way is to start the jiffy 
counter so it wraps after 10 minutes of uptime. That way you'll run into 
any bugs quickly. Either we should abolish the leap second or we should 
make leap second adjustments (back and forth) on a monthly basis to 
exercise the code.

This is a hard sell though...

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se