I keep getting a very weird lag where fps drop from 60 to 30 around create machines when I load a chunk with them, either by moving or loading a save.

You could think this is a issue with my computer but that is impossible, the instance is on a SSD, my computer has a 3 years old i7 running at 4ghz, it does not overheat. I am allocating 12 GB of RAM to Minecraft, and as for the GPU i have a 3090 RTX.
While playing Minecraft i close all other programs.

Plus the most telling sign is that, in a not laggy chunk, as long as i do not run away, unloading it, or close the save and reload it, i can build whatever i want without the fps falling from 60, but the moment i unload the chunk with machinery and then reload it, fps drop to 30.

This happens to me both on forge 36.0.13 with optifine 1.16.5_HD_U_G6 and on forge 35.1.36 with optifine 1.16.4_HD_U_G6.

This happens even with minimal septups as a single max level windmill around 10 gears and 4 machines.

Once the lag appears, even if you disengage the windmill, halting all, that only returns around 10 fps, leaving me at 40fps.

This issue has been marked as stale because it has been inactive for 3 weeks. It will be closed if it remains inactive for another 3 weeks.

This issue has been closed since it has been inactive for 3 weeks since it was marked as stale.

I have to add that if you remove optifine, this issue disappears, so it seems to be an incompatibility between Create and Optifine.

This may be related to the ticking issue, wherein forge 35.1.37 crashes, maybe the issue persists in other versions as well, only that instead of a full crash, causes several fps lag like I've been experiencing, but it may be also completely unrelated issue.

If I do shift f3, the pie of resources is representing rendering consuming 98% of the pie when this bug is occurring.

I do not add logs, since they do not add any useful information, there are neither Create nor Optifine related lines on the log when this bug happens.