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UK air traffic control meltdown

jameshaydon.github.io

31–40 of 459 posts

Re: UK air traffic control meltdown

#31
This is one of the many reasons there should be a universal data standard using a format like JSON. Heavily structured, easy to parse, easy to debug. What you lose in footprint (i.e., more disk space), you gain in system stability.

Imagine a world where everybody uses JSON and if they offer an API, you can just consume the data without a bunch of hoop jumping. Failures like this would vanish overnight.

Re: UK air traffic control meltdown

#32

And why could the system not put the failed flight plan in a queue for human review and just keep on working for the rest of the flights? I think the lack of that “feature” is what I find so boggling.

Because they hit "unknown error" and when that happens on safety critical systems you have to assume that all your system's invariants are compromised and you're in undefined behavior -- so all you can do is stop.

Saying this should have been handled as a known error is totally reasonable but that's broadly the same as saying they should have just written bug free code. Even if they had parsed it into some structure this would be the equivalent of a KeyError popping out of nowhere because the code assumed an optional key existed.

For these kinds of things the post mortem and remediation have to kinda take as given that eventually a not predictable in advance unhandled unknown error will occur and then work on how it could be handled better. Because of course the solution to a bug is to fix the bug, but the issue and the reason for the meltdown is a DR plan that couldn't be implemented in a reasonable timeframe. I don't care what programming practices, what style, what language, what tooling. Something of a similar caliber will happen again eventually with probability 1 even with the best coders.

Re: UK air traffic control meltdown

#33
post #26

Earlier quoted context omitted.

As is tradition =) (We actaully have no major issues with the French at least in my generation, its all just good fun)

It’s all good. We still take cheap-shots at English food and English women ;) Edit: I lived in London for 3 years. I miss it every day.

I wouldn't worry about it, we take cheap shots at French food and French people too ;)

Re: UK air traffic control meltdown

#34
post #19

Software has bugs, that's not really the damning part... The damning part is that in four hours and two levels of support teams, there was noone who actually knew anything about how the system worked who could remove the problematic flight plan so that the rest of the system could continue operating! What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input..…

They were probably on vacation

Re: UK air traffic control meltdown

#36
post #19

Software has bugs, that's not really the damning part... The damning part is that in four hours and two levels of support teams, there was noone who actually knew anything about how the system worked who could remove the problematic flight plan so that the rest of the system could continue operating! What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input..…

Just guessing:

They bought a software from a third party and treat it as a "black box". There are few known ways that the software fails, and the local team has instructions on how to fix it. But if it fails in an unexpected way, good luck, it's impossible for the local team to identify and fix the problem without the vendor.

The reason it took so much was they realized too late that they need to call the vendor.

Probably you have to blame managers rather than engineers in the support team.

Re: UK air traffic control meltdown

#37
post #19

Software has bugs, that's not really the damning part... The damning part is that in four hours and two levels of support teams, there was noone who actually knew anything about how the system worked who could remove the problematic flight plan so that the rest of the system could continue operating! What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input..…

> What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input...) To collect money on support contracts, I suspect.

Try to get developers who love to code and create to stay on a support team and be on an on-call roster. I betcha at least half will say no, and the other half will either leave or you'll run out of money paying them.

Re: UK air traffic control meltdown

#38
post #31

This is one of the many reasons there should be a universal data standard using a format like JSON. Heavily structured, easy to parse, easy to debug. What you lose in footprint (i.e., more disk space), you gain in system stability. Imagine a world where everybody uses JSON and if they offer an API, you can just consume the data without a bunch of hoop jumping. Failures like this would vanish overnight.

Broadly speaking I think this is done for new systems. What you need to identify here is how and when you transition legacy systems to this new better standard of practice.

Re: UK air traffic control meltdown

#39
post #19

Software has bugs, that's not really the damning part... The damning part is that in four hours and two levels of support teams, there was noone who actually knew anything about how the system worked who could remove the problematic flight plan so that the rest of the system could continue operating! What exactly is the point of these support teams when they can't fix the most basic failure mode (a single bad input..…

One important software engineering skill that is often overlook is the art of writing just the right amount of log, such that one could have sufficient information to debug easily when things go wrong, but not too verbose such that it will be ignored or pruned in production.

Re: UK air traffic control meltdown

#40

Earlier quoted context omitted.

It’s all good. We still take cheap-shots at English food and English women ;) Edit: I lived in London for 3 years. I miss it every day.

I wouldn't worry about it, we take cheap shots at French food and French people too ;)

Hold on, I think we take cheap shots at French people, but _expensive_ shots on the food and wine
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