6 ms·
Many parts of the world move forwards and back a full _hour_ every year. We complain about it but it’s mostly ignored. A gradual drift of a couple of minutes is
by lovecg 2y ago
Many parts of the world move forwards and back a full _hour_ every year. We complain about it but it’s mostly ignored. A gradual drift of a couple of minutes is fine.
- teruakohatu 2y agoIts not quite the same problem. Timezones are a transformation applied on top of UTC. If you are writing code, you are transforming the always increasing UTC to a more or less arbitrary dates and times. Moving backwards means you (your code) experiences the same time twice.
- ffsm8 2y agoKeep in mind that the earth is round and timezones switch an hour by area, so there is always some drift between the suns position and midday. So from my point of view, they were spot on
- jpitz 2y agoYou might be surprised to learn that there are time zones that are not an integer number of hours different from UTC.
- ffsm8 2y agoI'm always open to change my mind, but I struggle to see the relevance of that in this context. Are there timezone areas in the world which change their UTC differential fluidly throughout the year and by the yard to pin midday to the highest position of the sun? I'll definitely say that that'd not only surprise me but blow my mind if true! If there isn't ... Then what was your point?
- jpitz 2y agoYou claimed that timezones change an hour by area. That's not the case. That's my point.
- ffsm8 2y agoSo you don't have a point, because the only "claim" I had was - agreeing with the grandparent comment, because: there is always some drift between the suns position and midday Your point is about as coherent as saying CO2 levels in the air aren't going higher, because the sea is blue
- deleted 2y ago[deleted]
- lifthrasiir 2y agoIt is not exactly same, but it can be framed as the same problem by requiring every nation to change their own time zone once in a while. As long as the "once in a while" is not frequent (unlikely to happen before 2500, and should happen less than once per century for next 10K years), this should be okay.
- naniwaduni 2y agoAbout half of the world would 15+ minutes away from sun directly overhead at noon if hour-aligned time zones worked correctly, leapseconds are "solving" a "problem" at a level of precision wildly at odds with actual usage.
- mlyle 2y agoThere's the astronomical applications, where a second error corresponds to a couple of arcseconds of precision, which is just a bit better than most applications want.
- input_sh 2y agoIt's not that many parts of the world. DST is a very western "problem" that most of South and Central America, Africa and Asia simply don't have to deal with. We're the exception, not the rule.
- HeatrayEnjoyer 2y agoThe sun is everywhere. Time zones (and the reasons that spawned them) after everywhere. Why would they be magically free of it?
- mzl 2y agoDaylight savings time is not in a majority of countries. See the map on Wikipedia: https://en.wikipedia.org/wiki/Daylight_saving_time https://en.wikipedia.org/wiki/Daylight_saving_time
- HeatrayEnjoyer 2y agoWhy haven't they caught up to the west yet? Why are they doing it wrong?
- outworlder 2y agoFunny that you only consider North America as 'western'. Brazil, the largest country in South America, had DST until very recently (2019). A large chunk of South America observed DST at some point. Some stopped in the 90s, others stopped much more recently.
- mlyle 2y ago> > DST is a very western "problem" that most of South and Central America, Africa and Asia simply don't have to deal with. > Funny that you only consider North America as 'western'. No, he's including Europe, which mostly observes a summer time offset.
- aezart 2y agoI work in Arizona, and some of our software calls APIs on a server hosted in California. The California server expects timestamps in requests to be in Pacific time, with no timezone in the timestamp, and expects them to conform to daylight savings rules. This gets very hard to reason about because Arizona doesn't _do_ daylight savings. Like, what happens when we request 24 hours of data from them, on the day daylight savings time flips over? Do we want midnight-to-midnight data, or do we actually want 24 hours of data, which might wind up timestamped differently since there's a duplicate 2AM one day and a missing 2AM another day. A few years ago we had a contractor write some extremely messy code to handle cases like that, and soon it's going to be my job to try and refactor it into something readable.
- Mountain_Skies 2y agoIt's surprising how many vendors of security product refuse to use UTC for timestamps and insist on using the local time of their bay area data center. The number of edge cases that arise from DST issues that are significantly reduced, if not completely eliminated, by using UTC should be reason enough for security product vendors to see it as a core best practice.
- swores 2y agoI'm amazed to hear anyone doesn't use UTC, I'm not a professional developer and I remember learning, just while teaching myself the basics of PHP & MySQL as a teenager, that it's best to have databases store either UTC or a Unix timestamp (which afaik is essentially the same as using UTC except that it's less easy for most people to read at a glance) and to do the conversion to any local time zone wherever users interact with it.
- josephg 2y agoI have a rule of thumb that software works progressively worse the further you are away from the Bay Area - both geographically and culturally. For example, we use roundabouts (traffic circles) everywhere here in Australia and google maps still gives pretty terrible directions when driving on them. I was shocked the first time I drove on the 101 just how good the spoken directions are - but it makes sense given the actual Google maps engineers drive that road. If the directions were bad there, they would get fixed. I shudder to think how many bugs must show up for people who use right-to-left languages or use non-ascii charsets - especially before Unicode & emoji were popular. I’m ashamed to admit I don’t even know how to test if my software works properly in languages like Arabic. Of course software made in the Bay Area assumes the whole planet uses pacific time. I’m sorry to throw shade, but that’s entirely in character for the area.
- bergen 2y agoEven besides daylight savings time, timezones exist. England and Spain are on a vertical axis, yet the timezone differs by 1 hour. Cross the border from spain to portugal and time jumps a full hour, so there are people living 100 Meters apart with 1 hour time difference.
- shagie 2y agoTimezones are political and economic statements (and sometimes even religious - https://github.com/eggert/tz/blob/main/africa#L853 https://github.com/eggert/tz/blob/main/africa#L853 ). Things like China being all one timezone or India changing to IST after declaring independence https://en.wikipedia.org/wiki/Time_in_India#After_independence https://en.wikipedia.org/wiki/Time_in_India#After_independen... . An example of an economic change was https://en.wikipedia.org/wiki/International_Date_Line#Eastern_Kiribati_(1994) https://en.wikipedia.org/wiki/International_Date_Line#Easter... Trying to make sense of them as purely time keeping artifacts is bound to have misunderstandings.
- rjmunro 2y agoI've heard that this is why Spanish people go to bed so late. They are going to bed at the same solar time, it just seems later because of the time zone they are in. https://www.bbc.com/worklife/article/20170609-its-time-to-put-the-tired-spanish-siesta-stereotype-to-bed#:~:text=The%20Spanish%20also%20go%20to,pm%20and%20Italians%20at%2011pm https://www.bbc.com/worklife/article/20170609-its-time-to-pu.... > The Spanish also go to sleep later than their European neighbours. According to Eurostat, Spaniards go to bed, on average, at midnight, compared to Germans at 10pm, the French at 10.30pm and Italians at 11pm.
- creatonez 2y agoNote that political timezones are not baked into Unix time, whereas leap second corrections are.