Hy there,
I recently configured pidgin to access the chat and when I had to get the list of the rooms available, I had to wait 10 minutes (with pidgin using 100% of my CPU) before I got this list. Indeed there are really a huge amount of rooms because of all the clash.
I don’t know if how exactly it works but maybe it could be a good idea to close the rooms corresponding to old clash (more than 24 hours or more)?
A+.