I locally host and maintain some Minecraft (Java) servers for my kids and their friends. This morning, I kicked everyone off the servers while I did some routine maintenance. I finished with a standard sudo apt update && sudo apt full-upgrade
A few things were updated - PHP, a library or two, and the kernel from 4.19.0-16-amd64 to 4.19.0-17-amd64
All went fine.
After I was done, I rebooted the system and fired up the MC servers. As soon as a player joins an MC server, the CPU usage on all cores slams to 100% and stays there. The game is unplayable.
Nothing has changed with regards to the versions of game server, game clients, or Java.
Debian buster.
Oracle Java 16.0.1
Is there any way to downgrade back to 4.19.0-16-amd64 ... ?