FerriteCore vs Krypton

FerriteCore is a free, MIT-licensed coremod for Minecraft: Java Edition that targets RAM use. It reduces memory associated with block states, models, predicates, strings, voxel shapes and baked quads through a set of documented optimizations. Examples include replacing block-state neighbor tables with FastMaps, caching multipart model predicates, deduplicating model instances and reducing baked-quad memory. The project reports that individual techniques saved hundreds of megabytes in cited tests; one pack example showed post-garbage-collection memory moving from roughly 3.1 GB to 1.1–1.2 GB on the title screen. Several optimizations have no CPU impact during play, while some add load-time CPU cost. ThreadingDetector optimization is disabled by default because it may very rarely cause race conditions. FerriteCore supports Fabric, Forge, NeoForge and Quilt and is listed for Minecraft Java Edition versions 1.16.5 through 26.3, depending on loader builds. It is marked for both client and server use, and the maintainer recommends installing it on both because some optimizations apply server-side. Versions before 1.16 are not supported for backporting.

Krypton is a free Fabric mod that optimizes Minecraft networking and entity tracking, with its performance work directed mainly at servers. It works on both clients and servers, including dedicated servers. Its network handlers are based on optimized Netty handlers from the Velocity proxy, using native code where appropriate. Flush consolidation is intended to reduce server CPU use and tick times and lessen the impact of speculative-execution hardware vulnerabilities. Other small optimizations target memory use and packet serialization speed. Krypton is tuned for Linux, though it should work wherever Minecraft can run. CurseForge lists Fabric and Quilt as supported loaders. The project aims to work with Fabric API, Lithium, and Sodium; compatibility with other mods is best effort. It is licensed under LGPL-3.0-only, and the maker does not guarantee stability, compatibility, or support for every setup. The project is described as feature-stable, while updates for newer Minecraft versions depend on the maker's availability and need. Listed compatibility includes Minecraft Java Edition versions 1.16.2 through 1.16.5, 1.17.x, 1.18.1 through 1.18.2, 1.19.x, 1.20.x, 1.21.x, and 26.1 through 26.3.