PaperMC server software: Paper and Folia configuration, performance tuning and how it compares to Spigot and Bukkit.
Every entity, every block update, every redstone pulse — one thread, twenty times a second, 50 milliseconds a pass. Folia's answer is to stop sharing the kitchen. Here is the tick budget and the ownership rules, read from the PaperMC source.
Can't keep up! is not a hardware message. It's the server telling you a tick took longer than 50ms, and almost every cause is a default nobody changed. Here's what actually moves MSPT, with the flags that are now wrong and the setting that isn't where every guide says it is.
There is a fifteen-year fork tree underneath every Minecraft server, and most admins copy a jar without knowing what's in it. Here's the whole chain, with the code — including the config key most DAB guides get wrong.
Your server dropped to 12 TPS. You copied Aikar's flags. You upgraded Java. Nothing changed. That's because JVM flags don't fix plugin bugs. Here's how to find what's actually killing your tick budget.
Every six months the same thread appears and nobody maps the JVM engineering onto what a Minecraft server actually does. This does — version by version, with the flag most guides still tell you to set that will eventually stop your server from booting.
