dynmap

Quote from _ForgeUser7455706 https://dev.bukkit.org/projects/dynmap?page=140

Also, Mike has added a feature to Bukkit, which allows him to retrieve whole chunks quite fast. As an added bonus, we can access those chunks from different threads, which is why multi-threaded rendering is now possible ;). (the 'parallelrendercnt' in configuration.txt) All in all I think Dynmap allows enough configurations-tweaks to make it perform under most circumstances. Check out 'timesliceinterval' if fullrenders are hogging your cpu. If the main game is underperforming while doing fullrenders (or any renders), you might want to take a look at 'maxchunkspertick'