Lag spikes

Any one have an idea what is causing these . Like commands, players, regions/worlds that may be cuasing the problems?

well lets see here, with the new map we have ALOT of new terrain being rendered. There has been a lot of mob spawning lately as well as the main world is very much explored and the memory is at 50%, plus you have done stuff with nether and there has been a lot of world edit. oh yeah and i wanted to see what would happen if i made like 6 towers of cacti about 70ish blocks high and broke all the bottoms at the same time. that was fun.

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