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Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

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Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#181

Post by lesuorac »

lmm wrote: post #180
Shorel wrote: post #108

Earlier quoted context omitted.

I'm in total disagreement with your last paragraph. In fact, I can't see how it follows from the rest. Software can have defects, true. There are finite resources, true. So keep the tickets open. Eventually someone will fix them. Closing something for spurious psychological reasons seems detrimental to actual engineering and it doesn't actually avoid any real problem. Let me repeat that: ignoring a problem doesn't ma…

> There are finite resources, true. So keep the tickets open. Eventually someone will fix them. Realistically, no, they won't. If the rate of new P0-P2 bugs is higher than the rate of fixing being done, then the P3 bugs will never be fixed. Certainly by the time someone gets around to trying to fix the bug, the ticket will be far enough out of date that that person will not be able to trust it. There is zero value in…

But then when somebody else has the issue they make a new bug and any data/investigation from the old one is basically lost.

Like what's wrong with having 1000 open bugs?

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#182

Post by lmm »

jp57 wrote: post #147
lostlogin wrote: post #73

Earlier quoted context omitted.

It says ‘metric’. Good.

Though one could argue that the (original) definition of a meter and the definition of a nautical mile are equally arbitrary and yet similarly based. Originally 1 meter was one ten-millionth of the distance over the surface of the earth from the equator to the pole. One nautical mile is the length one arc-minute of latitude along a meridian. (About 1.85km).

They were. The difference is one is part of a standard system of units with sensible relations between different units in the system, and the other isn't; the specifics aren't what's important, the relations are.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#183

Post by Arainach »

lesuorac wrote: post #181
lmm wrote: post #180

Earlier quoted context omitted.

> There are finite resources, true. So keep the tickets open. Eventually someone will fix them. Realistically, no, they won't. If the rate of new P0-P2 bugs is higher than the rate of fixing being done, then the P3 bugs will never be fixed. Certainly by the time someone gets around to trying to fix the bug, the ticket will be far enough out of date that that person will not be able to trust it. There is zero value in…

But then when somebody else has the issue they make a new bug and any data/investigation from the old one is basically lost. Like what's wrong with having 1000 open bugs?

In becomes functionally impossible to measure and track tech debt. Not all of those issues are tech debt - things which will never be fixed don't matter.

Put another way: you're working on a new version of your product. There are 900 issues in the tracker. Is this an urgent emergency where you need to shut down feature work and stabilize?

If you keep a clean work tracker where things that are open mean work that should get done: absolutely

If you just track everything ever and started this release with 1100 issues: no, not necessarily.

But wait, of those 900 issues are there any that should block the release? Now you have 900 to go through and determine. And unless you won't fix some of them you'll have the same thing in a few months.

Work planning, triage, and other team tasks are not magic and voodoo, but on my experience the same engineers who object to the idea of "won't fix" are the ones who want to just code all day and never have to deal with the impact of a huge messy issue database on team and product.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#184

Post by bigiain »

amelius wrote: post #111
ericjmorey wrote: post #99

Earlier quoted context omitted.

Which company deployed a chaos monkey deamon on their systems? Seemed to improve resiliency when I read about it.

"Your flight has been delayed due to Chaos Monkey."

"My name is Susie and I'll be the purser on your flight today, and on behalf of the Captain Chaos Monkey and the First Officer Chaos Monkey... Oh. Shit..."

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#185

Post by eru »

chrisweekly wrote: post #178
RcouF1uZ4gsC wrote: post #173

Earlier quoted context omitted.

The same company that was in the news recently for screwing up a livestream of a boxing match.

True, but it's the exception that proves the rule; it's also the same company responsible for delivering a staggeringly high percentage of internet video, typically without a hitch.

Yes, though serving static files is easier than streaming live.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#186

Post by eru »

jp57 wrote: post #147
lostlogin wrote: post #73

Earlier quoted context omitted.

It says ‘metric’. Good.

Though one could argue that the (original) definition of a meter and the definition of a nautical mile are equally arbitrary and yet similarly based. Originally 1 meter was one ten-millionth of the distance over the surface of the earth from the equator to the pole. One nautical mile is the length one arc-minute of latitude along a meridian. (About 1.85km).

Yes, the nautical mile is actually les arbitrary than the 'normal' mile.

> Originally 1 meter was one ten-millionth of the distance over the surface of the earth from the equator to the pole.

Even more originally, they wanted to use the length of a pendulum that takes one second to swing. But they discovered that this varies from place to place. So they came up with the newer definition based on the size of the earth. And just like with all the subsequent redefinitions (like the one based on the speed of light etc), the new length of the metre matches the old length of the metre:

> [The] length of the string will be approximately 993.6 millimetres, i.e. less than a centimetre short of one metre everywhere on Earth. This is because the value of g, expressed in m/s^2, is very close to π^2.

The definitions matching is by design, not an accident.

See https://en.wikipedia.org/wiki/History_of_the_metre and https://en.wikipedia.org/wiki/Seconds_pendulum

If you want something less arbitrary, you can pick 'Natural Units': https://en.wikipedia.org/wiki/Natural_units

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#187

Post by eru »

Nevermark wrote: post #154
skykooler wrote: post #150

Earlier quoted context omitted.

"Hacker News failure caused by two units 12 orders of magnitude apart sharing 2-letter code"

We better get this sorted out before open source manned Mars missions. That all programming languages, down to statically typed assembly, don’t support something as simple to validate as unit consistency says something strange about how the science of replacing unreliable manual processes with automated systems is really bad at the practice of replacing its own risky manual processes with automated systems. If numeri…

> That all programming languages, down to statically typed assembly, don’t support something as simple to validate as unit consistency [...]

Many programming languages are flexible and strong enough support this. We just don't do it by default, and you'd need libraries.

Btw, units by themselves are useful, but not enough. Eg angular momentum and energy have the same units of Newton * metre, but adding them up is not recommended.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#188

Post by scarlehoff »

ianferrel wrote: post #114
andkenneth wrote: post #98

Earlier quoted context omitted.

No one is using nanometers in aviation navigation. Quite a few aviation systems are case insensitive or all caps only so you can't always make a distinction. In fact, if you say "miles", you mean nautical miles. You have to use "sm" to mean statute miles if you're using that unit, which is often used for measuring visibility.

Sure but I could imagine some kind of software failure caused by trying to divide by a distance that rounded two zero because the same location was listed in two databases that were almost but not exactly the same location. In fact I did when I first read the headline, then realized that it was probably nautical miles. That would be roughly consistent with the title and not a totally absurd thing to happen in the wor…

This is exactly what I thought q when I first read the title.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#189

Post by YokoZar »

lmm wrote: post #180
Shorel wrote: post #108

Earlier quoted context omitted.

I'm in total disagreement with your last paragraph. In fact, I can't see how it follows from the rest. Software can have defects, true. There are finite resources, true. So keep the tickets open. Eventually someone will fix them. Closing something for spurious psychological reasons seems detrimental to actual engineering and it doesn't actually avoid any real problem. Let me repeat that: ignoring a problem doesn't ma…

> There are finite resources, true. So keep the tickets open. Eventually someone will fix them. Realistically, no, they won't. If the rate of new P0-P2 bugs is higher than the rate of fixing being done, then the P3 bugs will never be fixed. Certainly by the time someone gets around to trying to fix the bug, the ticket will be far enough out of date that that person will not be able to trust it. There is zero value in…

Every once in a while I get an email about a ten plus year old bug finally getting fixed in some open source project. If it's a good bug accurately describing a real thing, there's no reason to throw that work away rather than just marking it lower priority.

Re: Air traffic failure caused by two locations 3600nm apart sharing 3-letter code

#190

Post by tovej »

chrisweekly wrote: post #178
RcouF1uZ4gsC wrote: post #173

Earlier quoted context omitted.

The same company that was in the news recently for screwing up a livestream of a boxing match.

True, but it's the exception that proves the rule; it's also the same company responsible for delivering a staggeringly high percentage of internet video, typically without a hitch.

That's not what an exception proving a rule means. It has a technical meaning: a sign that says "free parking on sundays" implies parking is not free as a rule.

When used like this it just confuses a reader with rethoric. In this case netflix is just bad at live streaming, they clearly haven't done the necessary engineering work on it.

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