[LEAPSECS] Coming of age in the solar system

[Poul-Henning Kamp]

In message <1283623216.9536.35.camel at localhost>, Paul Sheer writes:


>the software side I don't need to ask about - I've

>been working on their core C code for two years now.

>And...

>

>it works perfectly even if the time is completely wrong.

>Why? because none of the code depends, to-the-second, on

>the absolute time of day.


And because your code is time-agnostic, you are 100% sure that no
telco anywhere has any leap-second issues with any code they run
in their system ?

Do I need to remind you about the 3rd rule of software development:

	3. The only thing worse than generalizing from one example
	   is generalizing from no examples at all.


>> In my experience, [...]

>

>What you are saying is:


No, I said exactly what I said:  Very few of the leap second
induced anomalies gets recognized for what they are, fewer still
gets reported as such and since nobody thinks there is anything
that can be done about it, the reports gather dust.

To that I can add, that a lot of organizations have special
operational status across leap-seconds.  Basically they give
up trying to handle it correctly, and simply shut down/idle
their operation in a window around the leap second.

One example: Medicine production.

FDA and EU requires lot-tracking to the second.  It is cheaper to
not transfer any substances for a window of N minutes around the
leap second, thus avoiding any timestamps during the leapsecond,
than it is to qualify that all kit will do the leap second correctly.

I know several facilities of various kinds I which schedule their
yearly maintenance during leap-seconds, or shut down extraordinarily.

One particular paranoid installation shuts production, takes UPS
off-grid and runs on diesel during leap-seconds.

How many reports does that prevent from getting written ?

We don't know, but we do know that managers are willing to do a lot
of work to avoid even the risk of writing the reports..

Poul-Henning

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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