[ntp:questions] WARNING: someone's faking a leap second tonight

Martin Burnicki martin.burnicki at meinberg.de
Sun Aug 5 11:18:17 UTC 2012

Jeffrey Lerman wrote:
> The unfortunate combination of the bogus leap second and the
> newly-discovered (on July 1) Linux kernel bug related to leap-second
> handling means that bogus leap seconds have a much bigger-than-normal
> impact.

I think a main problem here is that there are many software developers who
are not aware at all that leap seconds exist, or they just don't care.

In the 1980's and 1990's there were leap seconds about once every 12 or 18
months, and most people working on stuff which could be affected by leap
seconds were aware of this and took care the leaps were handled correctly
since the next one was going to come "soon".

Then after Jan 1999 there was suddenly a period of 7 years without any leap
second, and people just forgot about them or didn't really care about leap
seconds anymore. Then for Dec 2005 a new leap second was scheduled which
already caused some trouble, and until the next leap seconds (Dec 2008 and
June 2012) there were intervals of 3 and 3 1/2 years. Hers a link with a
graph showing the UTC time steps due to leap seconds:

Martin Burnicki

Meinberg Funkuhren
Bad Pyrmont

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