This is a new issue specific to version 1.14.2. It doesn't apply to 1.14 or 1.14.1 because the server was running normally in those versions. This is a report for an issue that only occurred after this morning's upgrade to the latest version of minecraft.
Server is a vanilla minecraft server (running on Creeperhost). When a single player logs on, they report the game as unplayable (chopping down entire trees only for them to reappear, rampant rubberbanding, etc). Looking at the logs, I find the following messages:
[18:30:49] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 4817ms or 96 ticks behind
The longer the server stays running and the longer the player stays logged on, the higher the number of ticks the server runs behind. At one point, I saw the server report 10 seconds (10 thousand milliseconds) worth of ticks of lag.
This has resulted in a server that's literally unplayable so I've had to shut it down to avoid potential corruption to game save data.
its a issues with 1.14.2 thats happening on all multithreaded cpus...
at least it seems to be that...
i have tested it on a ryzen 1600 and a my old intel pc and it was doing the same but with disabled multithreading it didnt seem to...
the test was about half an hour tho could defently be something else...
but after checking it more i made sure that its NOT about:
RAM
GPU
INTERNET CONNECTION(yes it might cause something similar but thats simply your side)
Java version(only tested 3 versions)
.
It could be
CPU (posibly cause of the lighting)
the drive(HDD-SSD)
i didnt check cause i dont have a free SSD at the moment...
all of these ofc didnt happened on 1.13 so its that 1.14 is heavy on something ...
a posible solution for mojang after they find out what it is would be to make it distribute over several ticks instead of just trying to do a massive calculation in 1 tick...