I'm curious if there are any ways of lowering CPU overhead, specifically with magic users.
Normally on my server I notice a ~5% CPU usage per player (roughly, usually it's less), but I notice that when casters get going the average CPU usage can easily jet up an extra 20%. It makes sense that summons and AoE abilities would chunk up some extra CPU, but I'm worried if these numbers are a little farfetched.
I have heard that party play exasperates this problem, with each additional player acting as a data multiplier for the server. Is this only for party members who are in the same area? Is there anything that can be done to lessen this effect?
And finally, last but not least, assuming CPU raises steadily with each additional player, what exactly is the behavior of a server running at or near 100%? Is it constant lag, or just a shudder here and there when big events take place?
(Misc info that might/might not matter: 3.2Ghz Dual core (running on one thread), no custom heartbeats, CPU usage is near nothing when players are idle)