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Comment by laurencei | Hacker News Reader

Could this has been a deliberate/malicious act? Why else would someone post 20,000 consecutive characters of whitespace on a comment line?

Also, the "homepage" of StackOverflow does not show any 'comments' - it is just the top questions? Why was the page loading any comments in the first place?

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We don't think it was intentional. Maybe copy and paste, or something an editor did.

To clarify the "comment" was not a Stack Overflow comment, but rather a comment in a code block inside a question.

I am genuinly curious: how did you fix it? Did you remove the spaces first and then tried to use substring / trimming with proper testing done, or did you just implement it in place? I have faced similar dilemmas in the past, but I usually go with "put out the fire, then find the correct solution" approach.

Implement in place to put the fire out. Pushed to half the web servers, made sure it fixed the problem, then rolled it out the rest. Coding under fire :P

How did you test this on half? Accessing the single web server directly I'm guessing? Probably not public

May we see this code comment? Sounds interesting.

Imagine if they had only posted 10,000 or 15,000 characters, and it just slowed the site down. How fast would it have been noticed? Hours? Days?

Good monitoring (which I expect the SO guys to have) would have triggered on a spike in 95% or 99% response times so probably almost as quickly

Actually we average less than 10% CPU on the web tier... so anything over that warrants investigation. Graph of CPU during today's issue at https://twitter.com/Nick_Craver/status/755793398544601088

on a site like stackoverflow, I would think they get malicious requests like that all the time. Even if it wasn't malicious (perhaps an otherwise benign script gone amuk), I bet something like this happens very often.

It would be interesting to find out if something like this goes into their automated regression tests. :)

more likely select all copy + paste

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