As shown in the title, enter the world again after saving will cause the computer to freeze severely. During the fault, you cannot enter the task manager to force the end of the game process. You can only wait for more than ten minutes for load complete or use the launcher's forced shutdown function.
(I don't speak English, this text was typed through Google Translate, I'm sorry for the inconvenience)

what is the max ram of your settings in curseforge?

About 10240MB, also this problem doesn't only happen in single player games, it also sometimes happens when multiplayer games are disconnected and reconnected