The website today was sluggish starting around 12:30PM EDT. At around 1:15 PD EDT, the server began to struggle and eventually became unresponsive due to server resources being fully utilized. This led to the eventual server crash.
We've determined the issue to be related to abnormal traffic coming from the following IP address in Montreal, Canada: 18.104.22.168.
If you know this IP, give the owner a polite tap on the shoulder and tell him or her to CUT IT OUT! If this was you, CUT IT OUT! As servers and computers go, our existing connection throttling mechanism didn't work as optimally as we had hoped, but we'll be addressing that issue separately.
We can only assume the Montreal connection was scraping our website for content. That's the usual culprit when something like this happens. The other is denial of service, an attack meant to flood our web server with so many requests that it can't keep up with, eventually just hanging.
Regardless of motive, we're back up and running, and we'll be working on optimizing our systems so this doesn't happen again.