Every time someone joins my Minecraft Server the tps drop to 14-16 tps instead of 20 and I don't know why. Anyone an idea why that is? A plugin? I use paper 1.16.1 v.6 and I only have Open Inventory, Armored Elytra and Redye as plugins but I use datapacks. I run the server on a raspberrypi 4gb model B with 2524mb of ram.
According to this Raspberry Pi Minecraft V1.12 Server – Excellent Performance Guide blog, even a Raspberry Pi 4 is not very well suited as a Minecraft Server.
Should you try this?
Let me answer a big question right off the bat. Should you buy a Raspberry Pi just to run it as a Minecraft server? Absolutely not. If you just want to run a Minecraft server, especially one with more than a few people, you are much better off buying a realms subscription or one of the many dedicated Minecraft server options.
A few paragraphs later, the author describes their own setup, which includes a Raspberry Pi 4.
One of the reasons appears to be storage speeds:
Second question: Do you have fast Raspberry Pi storage? Because this tutorial will overclock your SD port from 50hz to 100hz. (Update: Since I wrote this article solid state storage has gone down so much in price that it makes much more sense!) If you have a good SanDisk A1 Class 10 card you should have no problems. However, although the risk is minimal, there is some risk of SD card corruption if you don’t have a high quality card. I am not responsible if your card dies, your Pi explodes, your house gets hit by a meteorite, or anything else that happens! This is solely at your own risk! These are very common overclocks though and the risk is minimal, but you have been warned!
What you can do to fix this
If using a dedicated server (or even a PC) is out of the question, you could try and follow the performance guide linked above. For Minecraft Server 1.14 or newer, you can try this newer guide instead.