ThreadTweak
What ThreadTweak Does
ThreadTweak is a small, single-purpose mod that improves and tweaks Minecraft's thread scheduling. It is a fork of Smooth Boot, carried forward for newer versions of the game.
Minecraft splits its work across several threads, and how that work is scheduled affects both startup and general responsiveness. ThreadTweak adjusts that scheduling so the game's threads are handled more efficiently, rather than leaving the default behavior untouched.
Because it only changes scheduling behavior, it does not add blocks, items, or any in-game content. There is nothing to configure in the world and no new mechanics to learn. You install it and the tweaks apply on their own.
It is most relevant if you want smoother loading and steadier thread behavior without a large performance mod. Since it is a fork of Smooth Boot, players who used that mod for the same purpose will find the same idea here, maintained for versions above it.