DataFixerSlayer (improves RAM usage)

Mod

by Vazkii

Removes the minecraft DataFixer to clear up the RAM it would use

Type

Mod

CurseForge Downloads

602,688

CurseForge ID

416519

Last Updated

Jul 28, 2026

Description

DataFixerSlayer

DataFixerSlayer prevents the DataFixerUpper (DFU) system from loading. The DFU is the system in charge of migrating worlds between versions, and ensuring everything is using the correct data for the version. Since in modding, we don't tend to migrate worlds between versions, the DFU is usually just sitting there doing nothing and using up space with the data it's storing.

WARNING

Please read this before using DataFixerSlayer in your world:

DataFixerSlayer removes an important component of the game's stability to improve performance. Before using DataFixerSlayer, please ensure the following:

If you're using an old world (that was started prior to the version you're currently playing) you use the Optimize feature on that world first.
If you migrate the world to a new version, uninstall DataFixerSlayer while you do so, and Optimize the world again before reinstalling it.
Take regular backups of your world.
Don't use this with another mod that removes the DFU, dear lord do not even think of using multiple of these.

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