[ntp:questions] Leap second to be introduced in June

Rob nomail at example.com
Mon Jan 12 10:35:23 UTC 2015

brian utterback <brian.utterback at oracle.com> wrote:
> On 1/11/2015 4:56 PM, Rob wrote:
>> Michael Moroney <moroney at world.std.spaamtrap.com> wrote:
>>> If I have a system synchronized with a public NTP source, which is 
>>> synchronized with an atomic clock that provides leap second info, and
>>> I am watching carefully, what will happen when the leap second hits?  Will
>>> my system suddenly find its clock off by 1 second and slowly drift to
>>> the accurate time provided by the NTP server?
>> That depends on what kind of system it is.
>> Carefully designed systems will do the right thing.
> Define "the right thing".
> To eloaborate, there is no "right thing". There are a whole bunch of
> "things" that are right for some people and not for others. That is the
> very reason that there isn't a right thing, because if there was one
> right thing all the vendors would have fixed their operating systems to
> do it.

"the right thing" is to jump over this leap second by inserting a 60'th
second in the minute at midnight UTC.

Of course there are several problems caused by inadvertent decisions in
the past (e.g. to let the Unix clock tick UTC seconds instead of TAI
seconds), but it is for the OS designers to decide how to work around
that problem and communicate it to their application and subsystem
designers so they can live with it.

However, I don't believe in an urge of operating systems vendors to
do things right.  Operating systems do what makes them money, even when
the resulting functionality is sub-optimal.  Keeping accurate and
consistent time certainly is not high on their list of priorities.

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