The server has been up for 2.5 days now and it's using 870mb.
There are only 5 maps loaded.
While i am typing this, 1 map unloaded and the memory stayed the same.
It seems the memory doesn't get free-ed after a map is unloaded.
When i count the GUI weight the total is around 70kb.
I must say that megaboid and triangle are used very often.