I recently making some maps of my surroundings. The map sever is very laggy and its a bit painful. Almost all the time my local and regional maps stays blank and even GUI mini map have holes and not refreshing images.
From what I see all maps are downloaded every time I open map (local, regional) or go to some part of world (GUI map). Am I right?
If that's true its the main reason for map server overload.
EDIT:
Hm. Maybe they are cached but cleared when changing "zones". When i walked into house and get back local map was starting to load again.