
Fault in Hong Kong Air Traffic system caused by exceeding 5500 user settings - dklsf
http://www.scmp.com/news/hong-kong/economy/article/2087944/hong-kong-air-traffic-system-fix-come-two-weeks-after-latest
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atonse
This just doesn't add up to me.

5500 is an odd number (not power of two) which rules out some kind of overflow
issue.

Was this some kind of fixed size database? Why would it have crashed when
storing 5500 rows?

Maybe storing that many hit a timeout, and maybe they were stored outside a
transaction, hence leaving the system in an inconsistent state? But that
wouldn't explain the database shutting down.

Maybe they were trying to store 5500 but hit a limit at 4096 before getting
there?

I feel something is lost in translation (between nerds and non nerds) in the
explanation for this outage.

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houst0n_
Yeah I had the same feeling; how could anyone writing something like an air
traffic control system design it in such a way that some failure/exception in
loading user settings causes the system to die?

This is probably a horrible mess of ancient java crap and the 5500 is just an
arbitrary number that the store couldn't respond to in time before the app
timed the con out; but having lived in mordor, a horrific data model which
would enable this sort of thing to be a problem isn't too big of a stretch of
the imagination.

My bigger question was what the hell kind of application needs 5k settings per
user.....

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cnvogel
It seems to be this one here... Auto Track III

[http://www.raytheon.com/capabilities/products/autotrac/](http://www.raytheon.com/capabilities/products/autotrac/)
[https://www.youtube.com/watch?v=QB4Qy6mNYWY](https://www.youtube.com/watch?v=QB4Qy6mNYWY)

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lm2s
This reminds me of junior (and sometimes not so junior) developers not
protecting against the full range of possibilities in conditions, and how hard
it's for some to understand that there's glitches that make the counter go +2
instead of +1 before arriving at the condition check.

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cpncrunch
Atrocious site. Popups before seeing site. Then difficult to scroll. Randomly
navigates to a new story when scrolling.

