It seems odd to me that they decision was to not solve it this way, but not how it will be solved going forward. Like, doesn't that effectively make everything more complicated/difficult?
The leap second’s time is up: world votes to stop pausing clocks
331–340 of 456 posts
Re: The leap second’s time is up: world votes to stop pausing clocks
#332Earlier quoted context omitted.
>Sometimes the best solution is not a technical solution (“halt the markets for 15 minutes before/after”) We've had an election recently, right on the day when DST changed. On the night of counting of the votes, the clock went 2:59 AM -> 2:00 AM. To save themselves trouble the Statistics Office instructed all vote counters that under no circumstances are they to enter or update anything in any system during the repea…
The interesting thing about DST is that it's not really repeating the hour, if you include the time zone offset in your time stamp. Here, look. Using the time zone for Norway in this example, with the `date` command on macOS. First the last second before DST ended in Norway this year. TZ=Europe/Oslo date -I seconds -jf %s 1667091599 2022-10-30T02:59:59+02:00 Then the second after. TZ=Europe/Oslo date -I seconds -jf %…
Perhaps another moral to add: ISO8601 solves a lot of problems.
Re: The leap second’s time is up: world votes to stop pausing clocks
#333Earlier quoted context omitted.
Sometimes it pays to be the most-prepared among your cohort. In this case, it would have paid so well that your cohort decided to work around it. It always pays to not be the least-prepared among your cohort. You'll get no sympathy if you're at the back of the pack, you'll just die.
Another moral of the story could be that sometimes it's best to have a people solution to a technical problem.
Sometimes yes, the best answer to "doctor, it hurts when I do this" is actually "then don't do that".
Re: The leap second’s time is up: world votes to stop pausing clocks
#334Earlier quoted context omitted.
> That'd test all the software paths. The daylight savings time bugs I've run into at pretty much every company I've ever worked at would beg to differ.
My favorite is comparing aggregated data across several time zones when DST changes happen.
Shouldn't you just aggregate based on UTC? Leap seconds still cause a problem here but daylight savings shouldn't matter.
Re: The leap second’s time is up: world votes to stop pausing clocks
#335Earlier quoted context omitted.
The moral is we get to hear your cool war story. Thanks for sharing! ...okay yeah that's not a moral, but still.
Great, here's another. $work had thousands of full custom, dsp-heavy, location measurement hardware devices widely deployed in the field for UTDOA locating cell phones. It used GPS for time reference -- if you know your location, you can get GPS time accurate around the 10's of nanoseconds. GPS also broadcasts a periodic almanac which includes leap second offsets: if you wanted to apply the offset to GPS you could de…
It seems the less likely an event is to occur, the less likely your vendor put work into handling it.
This recalls perhaps the biggest mistake in the GPS specification, the 1024-week rollover period. A timespan long enough to be impractical to test without expensive simulator hardware, short enough to be virtually guaranteed to cause problems in long-term installations... and long enough for OEMs to ignore with impunity. ("Eh, it's 20 years, by that time I'll be retired/dead/working somewhere else.")
Moral: timescale rollovers need to be designed to happen very frequently -- as in a few days at most -- or not at all. Unfortunately the leap second implementers didn't have that option.
Re: The leap second’s time is up: world votes to stop pausing clocks
#336I wonder if the idea of giving an irregular offset at regular intervals is in the cards. Having a unknown offset of x seconds every century, say, seems easier to implement than a known offset every unknown interval.
Re: The leap second’s time is up: world votes to stop pausing clocks
#337Earlier quoted context omitted.
It rotates itself in 23 hours and 56 minutes relative to the fixed stars . It rotates itself in 24 hours relative to the Sun . It is Earth's rotation relative to the Sun what people care about in most situations, because day and night depend on that, not on the position relative to some far-away stars.
24 hours is an average over the duration of the Earth's orbit around the sun.
Seems like a problem to be solved with more rockets!
Re: The leap second’s time is up: world votes to stop pausing clocks
#338Does anyone find it weird that the General Conference of Weights and Measures has acronym CGWM instead of GCWM?
Re: The leap second’s time is up: world votes to stop pausing clocks
#339Does anyone find it weird that the General Conference of Weights and Measures has acronym CGWM instead of GCWM?
It's CGPM, from French "Conférence générale des poids et mesures"
Re: The leap second’s time is up: world votes to stop pausing clocks
#340Currently software has to be built to accommodate leap seconds. They happen frequently enough that you'll find out within a few years whether your software breaks when time suddenly skips forward or backward. If we kick the can down the road such that eventually we'll need to add a leap minute, we're going to end up with software that was never written to expect time to change in such a way, hasn't had a real world t…
clocks get used for two distinct purposes, often at odds: - the measurement of durations. - the presentation of some timestamp in a way that the reader has some intuition for. that first purpose won’t be hurt by not tracking leap seconds. actually, a lot of applications will probably more accurately measure durations by eliminating leap seconds. if leap seconds (or minutes) really are of critical importance, we’ll re…
I agree with your separation between "duration" and "absolute point in time". But it doesn't solve the issue, because durations are often computed as the difference between two absolute points in time. You could get over this on your local machine with a local counter, but across network boundaries you need to rely on absolute differences.