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    Re: Time up for the leap second?
    From: Richard B. Langley
    Date: 2012 Jan 17, 22:59 -0400

    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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