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The leap second’s time is up: world votes to stop pausing clocks

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Re: The leap second’s time is up: world votes to stop pausing clocks

#191

Post by toast0 »

krick wrote: post #166
techdragon wrote: post #80

Hot take… Storing anything as UTC was a mistake and we should be using TAI for all storage and computation, only transforming into more human friendly formats for display to end users. This never needed to be a problem except we decided to make it harder to use TAI than UTC and so everything got built up off the backs of legacy bios level hardware supported UTC style clock behaviour, when we should have been using TA…

I'm not sure I support your "hot take" — it is hot and requires a lot of contemplation. But that's not the point, IMO. The point is, that there ALREADY EXIST both TAI and UTC. TAI is true monotonic (whatever it means in a relativistic universe) and doesn't make any compromises. UTC abolishes monotonicity in order to keep both the length of a second and the time relationship to the orbital rotation. They both work. Fo…

> For whatever reason (for obvious reasons that is, but doesn't matter) UTC was chosen in virtually any software system to keep time.

What was chosen really isn't UTC. Several UTC seconds in the past are not accurately representable in unixtime. Several unixtime seconds in the past are ambigious as to which UTC second they are.

Unixtime is awfully close to UTC time, but it's not the same. If UTC time stops inserting leap seconds and never has negative leap seconds, then they will be equivalent going forward.

Re: The leap second’s time is up: world votes to stop pausing clocks

#192

Post by lifthrasiir »

slavik81 wrote: post #182
krick wrote: post #166

Earlier quoted context omitted.

I'm not sure I support your "hot take" — it is hot and requires a lot of contemplation. But that's not the point, IMO. The point is, that there ALREADY EXIST both TAI and UTC. TAI is true monotonic (whatever it means in a relativistic universe) and doesn't make any compromises. UTC abolishes monotonicity in order to keep both the length of a second and the time relationship to the orbital rotation. They both work. Fo…

If you want to keep UTC matching the solar rotation, why do you specifically require leap seconds? Why not leap minutes? Or leap milliseconds? The choice of ±1 s as the acceptable error seems arbitrary.

It is worthwhile to look at the past; before leap seconds the disagreement with UT1 was handled by changing the rate of UTC slightly, and that's probably even worse than leap seconds. And for a while the unit of adjustment was less than a second, varying from 0.05 to 0.2 seconds. I believe enough people have complained about subsecond adjustments, and thus leap seconds have survived only because not enough people have complained at that time.

Re: The leap second’s time is up: world votes to stop pausing clocks

#193

Post by lifthrasiir »

schlowmo wrote: post #92
amflare wrote: post #34

Earlier quoted context omitted.

I mean, if chaos is the goal, then sure... Let me refer you to: https://qntm.org/abolish

> Do normal humans publish "waking hours"? Not typically. I believe I just fell in love with that idea. If this would become a social norm people would maybe stop trying to reach me in the morning. And I would know if it's too late to call others.

This can indeed happen when a significant portion of humanity lives in the space, and can trigger the biggest change to how we keep date and time.

Re: The leap second’s time is up: world votes to stop pausing clocks

#194

Post by gpvos »

cptskippy wrote: post #73
adamsb6 wrote: post #50

Currently 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…

In an enterprise environment, every leap second or TZ change invokes a ceremonious updating of anything using Java or a JVM. I suspect a lot of people would rather perform a once a century update than the bi-annual process they do now.

The thing is that there will be entire Java-like ecosystems that will have shorter longevity than the time between leaps. So practically all of them will have no facility for a leap at all.

Re: The leap second’s time is up: world votes to stop pausing clocks

#195

Post by clnq »

magnio wrote: post #57
micah94 wrote: post #52

Earlier quoted context omitted.

I'm for this. Get rid of timezones, AM, PM, DST, leap years, seconds, all of it! Imagine having to know just one time. It takes a bit to wrap your head around. But only because we've accepted all the confusion for so long. The sun is still going to be "up" in one part of the world and "down" in another. The little numbers on your clock don't change that. Why can't it be the same little numbers everywhere?

How do you know whether the sun is up or down in a place when all places have the same time?

I see people bringing this question up as a counter-argument for a unified time.

But how do you know whether the sun is up or down in any given place on Earth right now? You probably don't, if the place is a few thousand miles East or West from where you are. You'd have to look up its time zone. And doing that might not be that much different from looking up at what hour the solar noon is somewhere else.

Re: The leap second’s time is up: world votes to stop pausing clocks

#196

Post by [deleted] »

throw0101a wrote: post #110
ender341341 wrote: post #89

Earlier quoted context omitted.

Why have them at all? how many people do things where they actually matter? at the current rate it'll be ~9000ad before we hit an hour offset, and we do hour offsets twice a year, so if an hour off is okay why is 1 second off not?

> at the current rate it'll be ~9000ad before we hit an hour offset And the leap year problems of the Julian calendar weren't a problem… until they were. And then good luck coördinating things: * https://en.wikipedia.org/wiki/Gregorian_calendar#Adoption_by... * https://en.wikipedia.org/wiki/Adoption_of_the_Gregorian_cale...

[deleted]

Re: The leap second’s time is up: world votes to stop pausing clocks

#197

Post by AnotherGoodName »

layer8 wrote: post #177
techdragon wrote: post #80

Hot take… Storing anything as UTC was a mistake and we should be using TAI for all storage and computation, only transforming into more human friendly formats for display to end users. This never needed to be a problem except we decided to make it harder to use TAI than UTC and so everything got built up off the backs of legacy bios level hardware supported UTC style clock behaviour, when we should have been using TA…

Arguably, being able to perform calendar calculations without leap-second information (which you don’t have for the future) is more important in applications than maintaining to-the-second accuracy over calendrical timescales. What applications and date-time libraries should really do is differentiate between timestamps, calendar plus wall-clock time, and elapsed runtime. In most circumstances, only the latter would…

You don't have dst offsets for the future either. Those keep changing. That's not a blocker.

The straight up truth is that we created something in between. Some parts of earth sun alignment are in the time zone abstraction layer and leap seconds are in the seconds count layer. There's no real cause for this and we should have moved to TAI to fix this blunder long ago.

Re: The leap second’s time is up: world votes to stop pausing clocks

#198

Post by throw0101a »

bewaretheirs wrote: post #119
throw0101a wrote: post #85

Earlier quoted context omitted.

> This could be handled for civil/local time via an adjustment in the timezone definitions (something which happens a few times a year today), leaving the underlying UTC timebase unchanged. Like I said: it could become a huge coordination problem. * https://en.wikipedia.org/wiki/Gregorian_calendar#Adoption_by... * https://en.wikipedia.org/wiki/Adoption_of_the_Gregorian_cale...

it's really just a tzdata update for the vast majority of computer systems. That package updates several times a year. Get the revised rule in there a decade in advance and you're golden.

> it's really just a tzdata update for the vast majority of computer systems.

I don't think you understand how the tzdata works: the tzdata folks only update the contents after the civil authority for a region changes the law.

So first you have to get all the law makers to update what the legal statues say and then you "just" update the computer systems. The latter is the 'easy' part, it's the former that's the coordination problem.

And as someone who was around for the 2005 DST change, I can say that may also be quite the coordination problem. (Though I think code has gotten much better since then.)

Re: The leap second’s time is up: world votes to stop pausing clocks

#199

Post by oblio »

bahmboo wrote: post #172
hoytech wrote: post #103

In 2015 I was working at a "fintech" company and a leap second was announced. It was scheduled for a Wednesday, unlike all others before which had happened on the weekend, when markets were closed. When the previous leap second was applied, a bunch of our Linux servers had kernel panics for some reason, so needless to say everyone was really concerned about a leap second happening during trading hours. So I was assig…

You got paid to dig extremely deeply into a very complex and important problem spanning multiple systems and domains. You developed a plan, tested it and were ready to act. This is a hugely valuable learning experience few people even get a chance at, let alone solve. Too bad it doesn’t show up on your resume is the only downside!

Résumé, no.

Interview discussion? If you're any good at interviewing, it should.

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