Performance problem

Hello, I use PaperSpigot#110 [1.16.6]
I have 30 online players and 16TPS on my server.

Specifications:
CPU: intel i7 6700k
RAM: 10GB

The problem is that the server still has about 3GB of free RAM, and the processor is loaded by 60-70%. Everything is set up very correctly, experience (after 1.15.2) at least chew your ass.
Timings: https://timings.aikar.co/?id=b755d8b2e9494946b768eec2181984bb
CPU Profiler: https://spark.lucko.me/#YDhM0szlFV

I mean, it looks like entities. Reduce the mob caps or spawn ranges or something along those lines.

mob-spawn range: 5
view-distance: 6

spawn’s in bukkit.yml already cut by 30%

Try to increase number in bukkit.yml >> ticks-per >> monster-spawns to 2-4

And so stands at 2, If I bet more, the players will be unhappy

yeah, entities are really the bane of multiplayer survival servers.

might be disk?