Landscape Edit Layers Lag

Hi, I’ve noticed bad lag when using the Edit Layers option on a new landscape for a resolution of 500x500 and above. When not using this, I experience no lag, and sculpting is smooth. However, when I check the Edit Layers box, the Game Thread jumps up significantly as seen below:

My specs are:
CPU: I7 5930K
GPU: GTX 1080
RAM: 16 GB DDR4

if that helps.

I don’t know why this is happening, since does not Task Manager report any significant changes or spikes when sculpting. It looks like this is a CPU problem but I don’t know where to go from here.