The userscripts.org was unavailable to users on 29th April due to a DDOS attack. The site is again facing the DDOS attack today โ and unavailable to users again! :(
The site admins have described this situation as:
Being DDOS again, this time 10,000 to 100,000 attempts at requests per second... Trying to bring it back up with even more defenses please learn how to use setTimeout properly the load balancer is being overloaded ... ------------ There are ~10 scripts that are misbehaving. Our current thought is to modify them to fix their updaters... Most painful script is currently causing 109+ Mbps: By having the user download the entire source (~500k), each time the user loads their script If you are a script author please remember to use http://userscripts.org/scripts/source/(YOUR SCRIPT ID HERE).meta.js for your updating code.
The userscripts.org is facing this problems due to some hosted scripts, which are constantly making requests to the server. The site admins have also suggested the script authors to properly code the scripts.
This incident clearly indicates that the greasemonkey scripts need a much advanced (and secured) way for automatic updates.
:(
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Thanks for the heads up, I was trying to access the site today to no avail :(