F-ckin Leap Seconds, how do they work?

Saku Ytti saku at ytti.fi
Wed Jul 4 06:27:22 UTC 2012

On (2012-07-03 16:53 -0700), Owen DeLong wrote:

> Sure, but even with that, 99% of it has only a passing 'interesting' effect and
> then recovers.

Inclusive you no longer know order of events based on your logs, and
virtually none of your software are logging 60th second.
What are only interesting and what can cause with luck (or bad luck)
catastrophic failures is guess work, no one is going to review all the code
written, and almost all of it assumes monotonic time.

> > Quite. But it is not well known that unixtime travels backwards.
> In part because it shouldn't actually do so. It should simply chime 59 twice.

Chiming 59 twice is traveling backwards. It goes to what ever precision you
have between 59 and 00, then it goes back to 59 flat.


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