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Comment by gmiller123456 | Hacker News Reader

The physical effort of setting a clock is not the issue. Switching to "leap hours" would involve a good part of the world living with about 9am sunrise (or a 3:30pm sunset) for hundreds of years. It'd be a really hard sell to say that's actually better. DST is adjusting to the amount of daylight available, so there's not much of a negative impact. Systems that need to be more accurate just set their time zones to UTC. And one second every year or so is far within the accuracy of a typical computer clock, so anything that needs something better is already going to have a complex time synchronization system.

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For humans, it's no worse than folks today who live on a time zone boundary and cross it often. You might argue that for humans, the local solar time should be computed as a continuous function of longitude, leap seconds can be managed there, and we get rid of the concept of a time zone.

Computers are another story though, perhaps in the past "a typical computer clock" could be on the order of seconds off and be fine. When computers start to control things like wireless networks (cellular is a problem today, time accuracy is a design factor in evolving Wifi as well), those seconds turn into microseconds very, very quickly. The whole point of the article is to reduce unnecessary complexity in the existing complex time synchronization systems.

If you're running large infrastructure, the next leap second is going to cause an outage somewhere in your org, and the cost may be very large.

> Switching to "leap hours" would involve a good part of the world living with about 9am sunrise (or a 3:30pm sunset) for hundreds of years.

Can we switch to leap minutes instead? In the worst case it would mean to adjust the time once in 30 years, which means that astronomers and software engineers would have to deal with this problem no more than 3 times in a century. Fair enough IMHO.

> a good part of the world living with about 9am sunrise (or a 3:30pm sunset) for hundreds of years

So no real change to the status quo?

Yeah how ever will they live with having to wake up slightly earlier or later for their entire lives.

> earlier or later

My understanding was that leap seconds are only ever added. It’s not like this averages out over time. The problem is that because they are only added the effect is cumulative and eventually some future generation will be eating lunch at 00:00:00.

There is a provision for negative leap seconds. In practice, this has never happened.

Thanks, I skimmed the wiki and it sounded like they could only be added.

Hasn't happened, but it may actually happen in the next half-decade or so. If not, it's almost guaranteed to happen ~25 years from now.

So what is it about a system where everyone and every business adjusts their schedule slightly (I guess independently) of each other that is better than the leap second system we have now. Which, as I said earlier, is essentially the same thing, but done in a standardized way.

Timekeeping at the abstraction level where business hours exist is a lot more tolerant of 40 seconds of error than at the abstraction level where timekeeping primitives are implemented.

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