Entities are not unloading at your respawn piont

Entities wouldn't unload at your respawn point.

Where ever you set your spawn point, the entities in the area won't unload. 

This could easily cause a lot of lag 

 

How to reproduce. 

1. Set your spawn point in the nether or the overworld.
2. Nametag a mob near by.
3. Go 1000 blocks away or any other dimension.
4. Run command /testfor @e