When you run the "The Twilight Forest" mod, there are problems with server lags, play with a friend. And it is impossible to do nothing, blocks cannot be broken, it is impossible to kill a mob, everything lags very much and it is impossible to play, what could be the problem?
Mods which installed on server :
betteranimalsplus-1.12.2-9.0.1.jar
BetterFps-1.4.8.jar
BiomesOPlenty-1.12.2-7.0.1.2410-universal.jar
Bookshelf-1.12.2-2.3.590.jar
Clumps-3.1.2.jar
CTM-MC1.12.2-0.3.2.20.jar
EnchantmentDescriptions-1.12.2-1.1.20.jar
FastLeafDecay-v14.jar
Gravitation Suite-3.1.1.jar
industrialcraft-2-2.8.221-ex112.jar
ironchest-1.12.2-7.0.72.847.jar
jei_1.12.2-4.13.1.223.jar
journeymap-1.12.2-5.7.1.jar
Neat 1.4-17.jar
Patchouli-1.0-9.jar
stg-1.12.2-1.2.3.jar
TreeChopper-1.12.2-1.2.4.jar
twilightforest-1.12.2-3.8.689-universal.jar
UniDict-1.12.2-2.9.9.jar
WanionLib-1.12.2-2.5.jar
More of them is libraries or helper mods.
Core: Forge
Version: 1.12.2 (14.23.4.2766)