I played Skyfactory 4 in Minecraft for a long time at 30fps. But suddenly I only have 1-2 fps. I also increased the allocated memory (ram) at Twitch but did nothing. I also updated Java. Does anyone have an idea why?
You should assign less ram to Twitch so there's more for the game.
Otherwise in the Game Launcher you can give the game more RAM under the code of the version, by default the game has 2.
Didn't work I also tried 2560 mb but without success