Ask HN: Are systems ready for the first negative leap second?
7 points
8 hours ago
| 4 comments
| HN
It’s been 10 years since we had the last leap second and it looks like we will get the first negative one soonish. Are systems ready for that?
al_borland
46 minutes ago
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If we have positive and negative leap seconds, why are we doing anything at all? 1 second forward, just to go 1 second back 10 years later…
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wmf
7 hours ago
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Systems are absolutely not ready. Leap seconds are a bad idea and negative leap seconds are worse. Just don't do it and let the drift cancel out.
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Bender
7 hours ago
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Google's proposal is a smear. [1] Most time servers do not use smear. No idea what behavior it may introduce in places where sub-second time is important. Curious if all these bugs [2] were fixed specifically to deal with going backwards.

[1] - https://developers.google.com/time/smear

[2] - https://rivassec.com/leap-second-chaos-2012.html

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d00d0ff000
8 hours ago
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NTP.

By any other standard, most manually set clocks are up to a full minute off all the time.

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subscribed
5 hours ago
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Yeah, but we're thinking of systems where nanoseconds matter.

MiFID 2 alone forces sub-μs precision. Million times less than the leap 1 second.

NTP minute away is good for displaying date on the workstation, not for many of the devices that are critical to the modern world.

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cyanydeez
5 hours ago
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dont most systems that rely on sharp timing simply manage it themselves.
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subscribed
4 hours ago
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Yesno.

Sure they have their own time servers fed from the GPS, but they need to be _accurate_ in relation to the world.

But timestamps used by companies forced to use very accurate timing must be synchronised to UTC.

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