LoaderOptimization
Java mod listed for Minecraft 1.21. Downloads from the MC Java Mods app on Android.
⬇ Download on CurseForgeThe author built this one for Minecraft 1.21.1 on NeoForge. On other versions it may install and then do nothing.
Ever stared at the NeoForge loading screen wondering why it takes so long? LoaderOptimization gets to work before your world even loads warming up registries, caching resource metadata, trimming redundant class scanning, and pre-sorting event listeners so the modloader hits the ground running instead of stumbling through cold startup.
Once you're in-game, the built-in /loaderopt command gives you a live window into everything happening under the hood. Check your startup phase timings, inspect registry sizes by namespace, see tick stats, monitor your intern cache hit rate, pull a full JVM heap and GC breakdown, and run a complete one-shot analysis all without leaving the game.
Every optimization is individually toggleable from the in-game config screen. Nothing is hardcoded, nothing touches other mods' internals, and there are no mixins. LoaderOptimization works quietly alongside any other mod in your pack.
Features:
- Registry warm-up — pre-sizes hash maps before world load to eliminate freeze spikes
- Pack metadata caching — skips unchanged resource packs on reload
- Background resource scanning — offloads the mods folder scan to a daemon thread
- ResourceLocation intern cache — deduplicates repeated location objects during startup
- Slow tick detection — logs any server tick that exceeds your configured threshold
- Startup phase timings — see exactly where your load time is going
/loaderoptcommand suite — status, timings, ticks, registry, mods, memory, intern cache, full analysis, and reset
- Edition: Minecraft Java
- File type: .jar
- Minecraft version listed: 1.21.1
- How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
- Where to get it: Opens on CurseForge — not every file is mirrored on our own servers.
Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.
- Ships as loaderoptimization-1.0.0.jar — drop this file into the mods folder
- Download size: 30 KB
- Download link checked 3 Oct 2026 — working
These come from our own check of the pack file, not from the source page.