minecraft-client-expert

name	minecraft-client-expert
description	Expert knowledge for Minecraft Java Edition client optimization on Windows — FPS settings, NeoForge performance mods, shader configuration (Iris/Oculus), JVM flags, and PrismLauncher instance management. Auto-loads when discussing Minecraft performance, mods, shaders, or configuration.
triggers	["minecraft","neoforge","minecraft fps","minecraft mods","optifine","iris shaders","oculus mod","embeddium","prism launcher","prismlauncher","shader pack","jvm flags minecraft","minecraft optimization","java edition minecraft"]
invocable	true

Minecraft Client Expert

Comprehensive reference for Minecraft Java Edition client optimization on Windows. Scope: client-side FPS, NeoForge modded performance, shaders (Iris/Oculus), JVM tuning, PrismLauncher management.

Quick Reference

Topic	File	Use When
Vanilla FPS & Windows settings	FPS-OPTIMIZATION.md	Low FPS without mods, in-game settings
Shader installation & config	SHADERS.md	Iris/Oculus setup, per-tier shader tuning
NeoForge performance mods	NEOFORGE-MODS.md	Building a performance mod stack
JVM flags & Java selection	JVM-FLAGS.md	Memory allocation, GC flags, Java version
PrismLauncher config	PRISM-LAUNCHER.md	Per-instance settings, override system
Hardware profiling (PowerShell)	SYSTEM-PROFILING.md	Detecting GPU/CPU/RAM on Windows
Full optimization workflow	cookbook/optimize-instance.md	New instance setup, end-to-end tuning

Scope

• Edition: Java Edition only
• Loader: NeoForge (primary), Forge (secondary)
• Platform: Windows only (PowerShell for system commands)
• Launcher: PrismLauncher
• Focus: Client FPS, shaders, modded performance

Core Principles

1. Embeddium > OptiFine for NeoForge. OptiFine is unmaintained for modern modded play.
2. Iris/NeOculus > OptiFine shaders — better FPS, mod compatibility, faster updates.
3. ZGC Generational > G1GC for Java 21+ clients. Lower pause times, better frame consistency.
4. FerriteCore + ModernFix are non-negotiable in any modpack for RAM reduction.
5. Always profile first — run hardware detection before recommending settings.

Known Configurations

User's BMC5 instance (NeoForge 1.21.1) is a validated reference baseline:

• JVM: -XX:+UseZGC -XX:+ZGenerational -XX:+AlwaysPreTouch -XX:+UseStringDeduplication -XX:+UnlockExperimentalVMOptions -XX:+AlwaysActAsServerClassMachine -XX:+DisableExplicitGC -XX:+UseNUMA -XX:ReservedCodeCacheSize=400M
• Memory: 8192 MB min/max, PermGen 1024
• Java: Microsoft JDK 21 (bundled by PrismLauncher)

When to Read Reference Files

Read FPS-OPTIMIZATION.md when:

• User reports low FPS without a clear cause
• Asking for vanilla/base game settings to tweak
• Windows-level GPU and process optimizations needed

Read SHADERS.md when:

• Installing shaders for the first time
• Shader FPS is too low — need to tune settings
• Choosing between shader packs for a given GPU tier

Read NEOFORGE-MODS.md when:

• Building or auditing a performance mod stack
• Diagnosing mod compatibility (Moonrise vs C2ME, Embeddium vs Rubidium)
• Looking for the right mod for a specific bottleneck (RAM, entity lag, startup)

Read JVM-FLAGS.md when:

• Configuring memory allocation (Xmx/Xms)
• Choosing garbage collector (ZGC vs G1GC)
• Selecting Java version for a Minecraft version
• Crashes with OutOfMemoryError or severe GC pauses

Read PRISM-LAUNCHER.md when:

• Creating or importing an instance
• Configuring per-instance Java/memory overrides
• Understanding instance.cfg and mmc-pack.json schemas

Read SYSTEM-PROFILING.md when:

• Starting a new optimization session without hardware info
• Need PowerShell commands to detect GPU, VRAM, CPU cores, RAM
• Checking installed Java versions on Windows

Read cookbook/optimize-instance.md when:

• Setting up a new NeoForge instance from scratch
• Doing a full optimization pass on an existing instance
• User wants a guided, step-by-step workflow