Minecraft performance mods

Performance mods are not magic.

Good ones

There are a few extremely well-made, high-impact mods which are shoo-ins to every modpack. They makes the game faster with virtually no observable changes to the game.

Off the top of my head: Sodium, Lithium, FerriteCore, ModernFix.

Situational ones

Some performance mods have tradeoffs which may or may not be appropriate for your modpack and your tastes. Does the mod optimize a game feature by making its code more efficient, or by just preventing it from working correctly?

Maybe you can tolerate model pop-in when you walk around corners, so “entity culling” is fine. Maybe combat just isn’t that important in your pack, so mods that slow down AI ticking are okay. If Lithium wins some performance while maintaining perfect vanilla parity, then of course you can win even more by foregoing vanilla parity where it makes sense to do so.

Just know what you’re installing.

Snake oil

There are plenty of low-quality performance mods that technically optimize the game, but in ways that don’t matter. There was this mod called “Saturn”, which “improved” performance by:

• taking a hacksaw to “useless” Forge features that other mods, including Create, actually did use
• caching something that definitely did not need to be cached, wasting memory
• saving allocations such as a teeny tiny allocation that occurs every time an Allay entity is loaded - not every tick! just once!

Installing a mod at all has some associated overhead; the mod needs to be loaded into memory after all. Good mods punch way above their weight and installing them is clearly worth the cost of loading them. When you’re saving 8 bytes per Allay, the math is less clear. And when you’re breaking compatibility with obscure mods like Create it starts to become even more of a net-negative.

I think some developers are not performance experts and do not know how to make a performance mod, but (correctly!) sumrised that making an “optimization” mod is a really good way to get an awful lot of downloads awfully quickly, and on CurseForge and Modrinth that’s how you make money.

Canned air

There are mods where “whether this even does anything at all” is a hotly debated topic. I believe initial versions of the mod Memory Leak Fix changed something which did not appear to actually cause a memory leak?

Outright lies

Remember that one which “increased your FPS” by just presenting the same exact frame to the monitor 5 times in a row and counting that as 5 unique frames for purposes of the FPS counter? Good times.

Prevention is the best medicine

• Turn off shaders.
• Turn off HD / animated texture packs.
• Remove or tone down mods with complicated rendering effects.
• Lower the game’s resolution, especially if you have a 4k display.
• Lower your render and simulation distance. Even lowering it from 8 to 7 makes a huge difference.
• Close web browsers and Electron programs.
• Double-check you’re using the right video card.
• Double-check you allocated enough memory to the JVM.
• Use an updated version of Java, if possible, and do not bog it down with shitty flags.

and, of course,

• Lower your standards. Minecraft performs like shit. It’s fine.