Yahoo has multiple rooms for a game. For example, let's choose Chess.
For Chess, they have multiple rooms, and every rooms has multiple tables.
What would be the reason to have multiple rooms ?
Will the server be slower with 1 room and 10.000 tables than 10 rooms and 1000 tables for each room ?
If yes, please make me understand why. I know they use Sockets.
'The' server would probably run the same with 1 room. What makes you assume that every room runs on the same server? Usually splitting up a service is done as a simple way of spreading load between multiple boxes.
I imagine that choosing a "room" from a list of 10000 tables would prove to be a poor user experience, and reduces the amount of data sent back to the client during room selection.