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A similar approach is used to sync up the clock in the tower at
Westminster ("Big Ben" -- although that is really the name of the
largest bell in the tower) on the evening of the leap second by
gradually taking off some of the old pennies in a tray near the top of
the clock's pendulum.

-- Richard Langley

Quoting Frank Reed :

> You may reasonably imagine that this is easy and computers have it
> all programmed in, but it's an illusion. Computer code for
> networking has developed in an organic fashion. At the end of 2008,
> the folks who manage Google's servers chose to skip the leap second
> in the proper sense, and instead they inserted 1000 one-millisecond
> delays (equivalent) during the course of the day on December 31,
> 2008. As their official blog described it:
> "The solution we came up with came to be known as the 'leap smear.'
> We modified our internal NTP servers to gradually add a couple of
> milliseconds to every update, varying over a time window before the
> moment when the leap second actually happens. This meant that when
> it became time to add an extra second at midnight, our clocks had
> already taken this into account, by skewing the time over the course
> of the day. All of our servers were then able to continue as normal
> with the new year, blissfully unaware that a leap second had just
> occurred. We plan to use this 'leap smear' technique again in the
> future, when new leap seconds are announced by the IERS."
>
> -FER
>
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| Richard B. Langley                            E-mail: lang@unb.ca         |
| Geodetic Research Laboratory                  Web: http://www.unb.ca/GGE/ |
| Dept. of Geodesy and Geomatics Engineering    Phone:    +1 506 453-5142   |
| University of New Brunswick                   Fax:      +1 506 453-4943   |
| Fredericton, N.B., Canada  E3B 5A3                                        |
|        Fredericton?  Where's that?  See: http://www.fredericton.ca/       |
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