The problem
There are big performance issues with versions 1.13 and above of Minecraft.
A lot of lag spikes appear when the game loads and unloads chunks.
Also, when you open the pause menu of the game, a huge lag spike occurs.
Here are some videos of the problem...
A – When loading new chunks
[media]
B – When loading already generated chunks
[media]
C – When you open the pause menu
[media]
How to reproduce
1. Create or load a world in 1.13 or above
2. Once in play, press Alt + F3 to display the lagometer graph
3. Explore your world and keep an eye on the graph
Duplicate of MC-132135.