Comment by uo_throwaway

It actually falls over around 1000 clients if they're actually playing and encountering one another at any regularity. I have been contributing to a new RunUO based shard (http://www.uooutlands.com) that has become extremely popular and hit 2k clients online. The lag was pretty extreme at first, but after a few weeks of studying CPU profiles I rewrote a lot of the map search algorithms, plus a few other things, and it's scaling easily now. I plan to push the rewrites upstream soon. The emulator still has legs!