Since the 1.16.220 update, I am encountering massive frame drops occasionly in local worlds. Every frame drop lasts for about 5-10 minutes (lagging my whole system and hogging 100% CPU at the beginning) and drops to fps as low as 12-15.

-The drop persists even when both CPU and GPU are not fully loaded like you can see in the picture attached.

-The drop seems more likely to happen in jungles, but can also happen in other places rarely.

-Minimizing minecraft for a few seconds then maximizing it fixes the drop (until the next one happens).

Before the 1.16.220 update I used to get solid 60 fps while hosting worlds, now it is becoming an annoyance dropping my PC to performance lower than my low end mobile.

My PC specs:

Intel core i7-8565U

Nvidia Geforce MX130.

Update on the matter:

It seems that the issue is in my system not in minecraft (I thought it is minecraft but turns out that minecraft is the only app I use that loads the PC so hard to trigger this behavior), doing more tests I found out that my CPU during these lag spikes is running at 400MHz which is what is slowing down my system to a halt. Sorry for the inconvenience...