I don't know why this started happening, it will lower to like 10 fps and raise up again every 5 seconds or so. Here are my specs:
i7 8700k 3.7ghz
1x16gb DDR4 3200mhz RAM
GTX 1080ti
Java 1.8.0_ 51 64 bit
Read more: Why do I have major fps lags on minecraft?