Huge Lag Spikes 1.12.2

I’ve been running a Pixelmon server for a while. I’m not sure what happened, but one day, my server starts receiving these huge lag spikes where the whole server will just freeze for up to ten seconds at a time at seemingly random intervals. I’ve looked at the timings report and I’m not sure exactly what could be causing the issue. The memory for the server seems fine too. If anyone could help out, that would be great!

spark plz. for more readable

Have you pre-generated your world? It looks like there’s a fair bit of world gen going on which generally is very slow