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Tell HN: Sudden Chile daylight savings time rules change causes chaos

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Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#51

Post by Mountain_Skies »

This seemingly almost happened a year or two ago in Georgia (the US state, not the country) when the legislature overwhelmingly supported ending the twice a year time change. But much like the public, the legislature couldn't agree on if they should go to year around standard time or year around daylight saving time, with one house passing standard time overwhelmingly and the other house passing DST overwhelmingly. There's no good reason for the two houses to each have such strong affinities to one system or the other, which makes me think the two houses may have had an agreement to look like they tried to address the issue that the public wants settled once and for all without actually passing something that would make half the state upset no matter which way they went. Or the party whips in both houses are simply very effective in gaining consensus in their own chamber.

IIRC, one of the bills was to go into effect the year it was passed, which would have been extremely short notice for the IT world to deal with.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#52

Post by ithkuil »

tgv wrote: post #44
ithkuil wrote: post #30

Italy has not yet made a decision on a whether DST will ever end this year and I suppose the situation is similar in other European countries. I can't even imagine the chaos if each EU country makes their own choice last minute

I don't think they can do that on their own, can they? There's still an EU wide rule on DST. They never revoked it, AFAIK.

In 2018, the European Parliament voted to get rid of twice a year clock changes. It came after a poll of 4.6 million EU citizens showed strong support for scrapping it.

I'm not sure however what's the process of getting this actually implemented.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#53

Post by gerikson »

Here is Microsoft's interim guidance for the change

https://techcommunity.microsoft.com/t5/daylight-saving-time-...>

In my experience MSFT does a stellar job within the limits of what's possible to accommodate TZ/DST changes.

As per the TZ Info mailing list, the change was committed on 9 Aug:

https://mm.icann.org/pipermail/tz/2022-August/031777.html>

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#54

Post by tsimionescu »

foepys wrote: post #29
MobiusHorizons wrote: post #22

Earlier quoted context omitted.

It’s one heuristic, but you can’t know what they want, the problem is underspecified. It’s reasonably likely they could want a reminder to watch a game that is being broadcast from a different time zone, or call a friend in a different country.

But this is one more reason to save the timezone and stop calculating on current data? Save the time and timezone of the event in the other country, so literally the time it starts not the calculated local time. Unless the other country decides to switch timezones, well then you are screwed.

That assumes you know what timezone the user intended. If I read somewhere that some football match in Chile is happening on November 1st at 1 o'clock, I may well put in a reminder for November 1st at 1 o'clock, without specifying a timezone or location. The calendar/reminder app would of course be unable to notify me that Chile's time for November 1st has changed, since I never told it anything about Chile.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#55

Post by mike_hock »

hilbert42 wrote: post #23
sjsdaiuasgdia wrote: post #15

Earlier quoted context omitted.

Far more coordination with this than something like Y2K. This is a government deciding the rules of time have changed in some way. Y2K, the rules of time didn't change, but a pattern of implementation decisions frequently used over the previous few decades broke down. A system that needs to know about the rule change has to actually receive it in some way. It has to be connected or the update has to be brought to it.…

The fundamental problem is that we humans are slaves to our computer systems instead of them being our slaves. By definition, a computer is a streamlined process or procedure designed to help humans but that's so often not the case. (Something that's so often overlooked.) The fact is that the biggest problem in computing is that their ergonomics suck big-time. This daylight saving issue is yet another instance of it.…

No, the fundamental problem is that DST is an ill-conceived concept, and being forced to inscribe it in software exposes all the contradictions and inconsistencies.

As another poster said, when is 1:30am on November 6th in Ontario?

The only thing this has to with computers is that we do all organizational stuff with computers nowadays. Changing DST on short notice would have caused chaos in the 19th century as well.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#56

Post by TJSomething »

spiffytech wrote: post #20

This kind of thing is why it's important to store user-specified future dates as local time + IANA zone name. If a user wants a calendar event at 9am, they probably still mean 9am after accounting for time zone or DST changes. Storing dates as UTC is appropriate for dates in the past, or future dates that a user will never expect to happen at a certain wall-clock time. (An IANA zone name is something like America/New…

I like keeping the offset and the zone name. Then, if there's a discrepancy, I can ask the user what to do about affected events.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#57

Post by hilbert42 »

sjsdaiuasgdia wrote: post #45
hilbert42 wrote: post #40

Earlier quoted context omitted.

Politics can change faster than the time it takes to lick a postage stamp and can do so in the most unpredictable ways. That's been a fact of life for the whole of human existence. That said, a processor can do billions of operations in the time it takes to lick a stamp. Thus, there's plenty of leeway there to ensure that computers don't even enter the political equation.

My point is that ergonomics and design is secondary to connectivity (continuous, intermittent, sneakernet, whatever) for a great deal of systems that need to care about time, including the latest political whims regarding time. The fastest processor ever created can't do anything with information it doesn't have.

"...with information it doesn't have."

That's my point. But when it eventually gets that info it shouldn't be impeded in updating as is the present system.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#58

Post by tsimionescu »

hilbert42 wrote: post #27
lifthrasiir wrote: post #17

Earlier quoted context omitted.

Well... https://qntm.org/abolish Time zones are fine. Random time zone offset changes are not.

"Random time zone offset changes are not." Are you saying that our computer systems are so inflexible that we cannot make them do our bidding? The issue here has nothing to do with whether daylight saving is appropriate or not, rather it's about the inability of computers to adapt quickly. When I was studying computing I had a textbook titled Problems for Computer Solution, it was about how to get computers to do our…

Most computers adapt just fine. International travel and cooperation are the real problem, especially in our increasingly globalized world.

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#59

Post by wil421 »

Mountain_Skies wrote: post #51

This seemingly almost happened a year or two ago in Georgia (the US state, not the country) when the legislature overwhelmingly supported ending the twice a year time change. But much like the public, the legislature couldn't agree on if they should go to year around standard time or year around daylight saving time, with one house passing standard time overwhelmingly and the other house passing DST overwhelmingly. T…

Not exactly what happened in the end. The house and senate in Georgia agreed on DST. However we can’t change to permanent DST yet. By Federal Law an act of Congress has to happen to change the law.

https://www.fox5atlanta.com/weather/permanent-daylight-savin...

Re: Tell HN: Sudden Chile daylight savings time rules change causes chaos

#60

Post by avip »

chrismorgan wrote: post #18

This is not novel. Look through the tzdb news and you will find many instances of similar and considerably shorter periods of notice. Just to pick a couple from last year that are unambiguous and well-documented (most you’ll have at least a bit more trouble finding first-party announcement of): 2021d: Fiji gave a month’s notice on suspending DST for the season. 2021b: Samoa gave less than a week’s notice on cancellin…

Samoa also famously skipped the 2011-12-30.

Maybe "famously among software developers" is more on-point.

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