Why would I be getting TPS lag spikes every 30 seconds on a single player local client world? [closed]

Solution 1:

The game, even on singleplayer, is separated into a client and server. This means that the server can lag behind (tick lag) without the client experiencing an FPS drop.

This is likely caused by what appears to be a fairly extensive Thaumcraft setup, and the server being unable to keep up with the processing. Other mods or events in the world may also be contributing, although we'd need a world file and list of mods (F3 says you have 20) to work out what else could be causing the lag.

Changing graphical settings will most likely not help. You can try reducing the number of loaded chunks, shutting off machines and mechanisms when you do not need them, or uninstalling unnecessary mods.