[ale] OT ntp - leap second - how many knew what this was 3 weeks ago

[John Pilman]

I knew about leap seconds, but I never kept up with when they occurred.  My
oldest son recently called so we could celebrate his one billionth second
since birth.  He mentioned that in determining the appropriate second, he
had to account for fifteen leap seconds since his birth.  It was a fun
celebration, even though it only lasted a second.

I have never programmed any system level applications, but I have
programmed data acquisition and reporting systems many times.  I never had
any trouble with adjusting the time on any of them.  For me, there has
always been the assumption that no two clocks could be expected to show the
same time.  So periodically making an adjustment was natural and did not
cause trouble.  We have some SQL Server apps which will not respond to
queries if the client's clock is more than five minutes different from the
server's, but we don't let them get that far apart.

On Wed, Jul 4, 2012 at 10:39 AM, Ron Frazier (ALE) <
atllinuxenthinfo at techstarship.com> wrote:

> Hi all,
>
> Around the beginning of this year, I was doing quite a bit of research
> into ntp and gps and eventually set up my own gps based ntp time server in
> both Linux and Windows. At the end of June, a leap second was inserted into
> the time sequences of the clocks on Earth. For those that may not know what
> that is, the atomic clocks are coordinated with the earth's rotation, so,
> for example, when the clock says noon, the sun is always roughly overhead.
> However, the earth's rotation speeds up and slows down at times.
> So,sometimes, we have to tweak the clocks to match the earth again. At the
> end of June, an extra second was inserted. Normally, the seconds go 58 ...
> 59 ... 00. This time, they went 58 ... 59 ... 60 ... 00. As it turns out,
> this crashed a number of servers.
>
> I find this very interesting, and somewhat scary as a potential
> programmer. Since I'm thinking of learning programming again, and since I
> have an interest in timekeeping, I have considered writing a world clock
> program etc., to show the time in different parts of the world. However,
> prior to my NTP research, I never knew about the leap second. So, there
> would have been a good possibility, had I written the program prior to this
> year, that my program would have crashed as well.
>
> So, my question is, how many of you knew about leap seconds prior to this
> incidence of it and prior to my describing it. If you were writing a clock
> program, would you have known to account for this?
>
> Sincerely,
>
> Ron
>
>
> --
>
> Sent from my Android Acer A500 tablet with bluetooth keyboard and K-9 Mail.
> Please excuse my potential brevity.
>
> (To whom it may concern. My email address has changed. Replying to former
> messages prior to 03/31/12 with my personal address will go to the wrong
> address. Please send all personal correspondence to the new address.)
>
> (PS - If you email me and don't get a quick response, you might want to
> call on the phone. I get about 300 emails per day from alternate energy
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> quickly.)
>
> Ron Frazier
> 770-205-9422 (O) Leave a message.
> linuxdude AT techstarship.com
>
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