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'Leap Seconds' May Be Eliminated From UTC
angry tapir writes "Sparking a fresh round of debate over an ongoing issue in time-keeping circles, the International Telecommunications Union is considering eliminating leap seconds from the time scale used by most computer systems, Coordinated Universal Time (UTC). Since their introduction in 1971, leap seconds have proved problematic for at least a few software programs. The leap second added on to the end of 2008, for instance, caused Oracle cluster software to reboot unexpectedly in some cases."
They aren't predictable in advance. They are basically the noise in the solar system's timekeeping. It's impossible to write code that knows in advance when they will occur, since they are only announced six months ahead of time. So any clock that wants to stay in sync with UTC must be connected to either NTP or GPS or similar timekeeping service.
If only those darn astronomers didn't care so much about keeping the sun at Greenwich precisely at the meridian at high noon, we wouldn't have this problem.
The determined Real Programmer can write Fortran programs in any language.
Isn't the problem with Oracle here? It should not be that difficult to fix their software. What's the difference with Summer time change?
The difference with spring/fall time changes is that although the local time may change, the UTC time does not. In other words, your offset from UTC (eg: GMT-8) may get adjusted depending on your location's observance of daylight savings time but UTC itself simply marches on oblivious to anything. The leap second is the one exception.
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Yeah, leap seconds suck, but the proposed solution (to let UTC drift farther and farther away from reality) sucks even harder. UTC should just be abolished in favor of UT1. Computer clocks are so crude anyway (mine is off by 3 seconds right now) that the supposed benefits of UTC's constant second are really non-existent, every computer needs to have its time adjusted now and then no matter what.
And that is what NTP is for. To automatically adjust the computers clock to account for drift.
..or its actually difficult to 'handle' leap seconds. I can tell that you've never worked seriously with time values as a programmer.
If you can't answer "When will each of the next 10 leap seconds be?" and "When were the last 10 leap seconds?" then you are pretty much fucked from a programming standpoint of 'handling' it in any sane manner using common time encodings, which use a count of intervals (usually seconds, or milliseconds) since some specific date and time.
Leap seconds make it impossible to incorporate them into intervals because leap seconds are not computationally predictable.
They are simply arbitrary announcements from the time keepers "we are adjusting the clocks by 1 second on such and such a date. We dont know when we will adjust them again.. we'll keep you posted."
Leap seconds are not like leap years, which are easily handled because they are introduced systematically based on only the interval value.
"His name was James Damore."