When Computers Go Wrong

Barence writes "PC Pro's Stewart Mitchell has charted the world's ten most calamitous computer cock-ups. They include the Russians' stealing software that resulted in their gas pipeline exploding, the Mars Orbiter that went missing because the programmers got their imperial and metric measurements mixed up, the Soviet early-warning system that confused the sun for a missile and almost triggered World War III, plus the Windows anti-piracy measure that resulted in millions of legitimate customers being branded software thieves."

Comments

Computers do what they are told to

[adosch]

TFA article should have been named the 'Worlds ten most calamitous logic cock-ups' instead. Because in the end, malformed, ill-tested or and unforeseen logic compensation(s) caused those issues, not computers themselves.

Re:Computers do what they are told to

[jc42]

Another aspect to this is a common property of most "digital" computations. I've seen it expressed as "Digital errors have no order of magnitude". Another phrasing is "Getting one bit wrong is generally indistinguishable from randomizing all of memory". So when a digital calculation goes wrong, a tiny, inconsequential error is just about as likely as a total meltdown of the entire system.

Programmers tend to get familiar with this phenomenon very early in their career. They write a small chunk of code that does a simple calculation, and the result is orders of magnitude wrong. When they investigate, they discover it was caused by a one-character typo, perhaps an "off by one" error such as using '<' instead of '<=', or vice-versa. This quickly leads to what many "normal" people consider the major character failure of software geeks, the insistence that everything be exactly right, no matter what, and the willingness to spend long hours discussing insignificant minutiae as if they mattered. In their work, it's usually such insignificant minutiae that brings the whole house of cards tumbling down.

If you're unwilling to take the difference between a comma and a simicolon seriously, you have no future as a software developer. This is often why something goes badly wrong and we have events like those described in this story.

OTOH, it is interesting that, despite all the software disasters like the metric/imperial-units story, the software world has never insisted that programming languages include units as part of variables' values. It's not like this is anything difficult, and it has been done in a number of languages. But none of the common languages have such a feature. It is a bit bizarre that we can get into long discussions of complex, obscure concepts such as type checking or class inheritance, when our calculations are all susceptible to unchecked unit mismatches (without even a warning from the compiler or interpreter). There's a lot of poor logic when the topic is the relative importance of various sources of bogus calculations.

"Black day for power programmers" Windows virus

[Locutus]

to comments, I thought the deal with the big blackout was that the network(TCP/IP) was flooded with a Windows virus infection and if you know TCP/IP, it's not very good with lots of traffic. There was so much traffic that the computer( a UNIX box ) sending status messages to the control room display system could not get messages out of it's buffers. TCP/IP does this thing where the message isn't put on the network if there's going to be a collision and it waits some before trying again. With the network flooded with Windows based computers trying to infect each other, the warning messages were stuck in the UNIX box and eventually the buffers filled up as more and more warning messages queued up. They seem to be blaming the UNIX box software because the software ended up crashing because they didn't catch the situation where they buffers overflowed. IMO, that was caused by Windows and it's ability to be a great petri dish for viruses and the idiots who keep putting Windows systems on critical networks.

The second comment I have on this is about missing the LAX Communications system software crash which caused multiple near misses on the tarmac and in the air when air traffic controllers could not communicate with pilots because of the crash. The cause of the software crash was a UNIX system was replaced with a Windows based system which had a known flaw. The flaw was that the OS could not run for more than 39 days no matter what was running on it. The system and software was still approved and put inplace with a maintenance instruction of rebooting the computer every 30 days. In comes a new employee who sees things are working fine so he/she doesn't reboot the computer and 9 days later the system crashes. The backup does the same and both are unable to recover and it takes hours to get the system back running again. That should have been in the list IMO.

There was also the CSX Railway situation when lots of its signals go offline because they are run by Windows and their Windows computers got a virus.

It would be nice to see a more complete and more accurate list of these kinds of computer software failures.

LoB