We need to test leap smearing :)

[Gary E. Miller]

Yo Fred!

On Thu, 22 Dec 2022 17:00:37 -0800 (PST)
Fred Wright via devel <devel at ntpsec.org> wrote:

> On Wed, 21 Dec 2022, Hal Murray via devel wrote:
> 
> > Google says:
> >  https://developers.google.com/time/smear
> >  We encourage anyone smearing leap seconds to use a 24-hour linear
> > smear from noon to noon UTC.
> >
> > There were earlier versions which did sine rather than linear.  
> 
> Hmm.  I don't recall any nonlinear version (and I presume you meant
> raised cosine rather than sine), but I do recall that Google's smear
> interval was originally 20 hours, not 24.  If you make it 24 hours,
> there's the question of whether that means 86400 seconds or 86401. :-)

There are many strange smearing schemees.  From a few hours to 48 hours. 

Google: On Feb 15 Google said they smear linear, over 20 hours,
centered on the leap second.

Previously Google said this:

https://googleblog.blogspot.com/2011/09/time-technology-and-leaping-seconds.html

    lie(t) = (1.0 - cos(pi * t / w)) / 2.0 

AWS smears linear for the 24 hours preceeding the leap second.

Some versions of NTP and chronyd, can ignore the leap second, then slew
the system clock to catch up:

https://developers.redhat.com/blog/2015/06/01/five-different-ways-handle-leap-seconds-ntp#options_with_ntpd

And of course:
    https://xkcd.com/2266/

The madness goes on, the only way to win the game is not to play.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
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