So, I know that chunk loading is something that usually affects performance, or causes some lag spikes, but this didn't happen until now.

When the chunks load, the FPS drops from 60 to around 20-15. My computer is INCREDIBLY low-end, but this wasn't an issue, at all.

It's a problem when every time you face another direction, the chunks unload, and when you turn around again, the game has to re-load them all. This means that gameplay is just the FPS jumping from 60 to 20FPS all the time.