Server keeps crashing - no plugins installed

I am running 1.7.9 beta R 02, and the server keeps crashing with this error: http://pastebin.com/YfF2Dths

When someone goes into a new jungle chunk, the CPU is maxed, and the server crashes shortly afterwards. When someone goes into a mega taiga (if it has not been generated), it crashes instantly.

memory usage is normal, all the time, and no plugins are installed. If it helps I get the same problem with R03 1.7.9 Spigot.

 

Ah, I know why, I am pretty sure, are you using the Minercraft.net website to host your server? If you are, that website isn't very good for hosting a server, unless you know how to use it well...

If you aren't using the Minecraft.net website, just try and switch it to 1.7.2 or 1.7.4

 

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