How to Get Rid of Unused Chunks in Minecraft

Getting rid of unused chunks in Minecraft can improve performance and reduce the size of your world save. There are several methods to achieve this, depending on whether you’re playing single-player, on a server, or using specific tools. The most common methods involve using chunk trimming tools, server commands, or manually identifying and deleting unused regions. These methods effectively remove data associated with chunks that haven’t been heavily used, freeing up valuable storage space and potentially boosting your game’s responsiveness.

Understanding Minecraft Chunks

Before diving into the methods, it’s crucial to understand what Minecraft chunks are. A chunk is a 16×16 block area that extends from the bottom to the top of the world. Minecraft loads chunks around the player, enabling gameplay. Chunks are loaded, processed, and unloaded, and only a certain number are active at one time. Unused chunks are unprocessed by the game and do not process any of the game aspects.

Methods for Removing Unused Chunks

Here’s a breakdown of common methods:

1. Using a Chunk Trimming Tool (For Single-Player and Backups)

Third-party tools are the most effective way to remove unused chunks. One such tool is MCA Selector.

• Download and Install: Download MCA Selector from a trusted source.
• Open Your World: Load your Minecraft world using the tool.
• Select Unused Chunks: MCA Selector lets you visualize your world map. Use the filtering options such as InhabitedTime to select the area you would like to remove.
• Delete Selected Chunks: Delete the selected chunks.
• Backup First: Always back up your world before making any changes with third-party tools!

This is the most precise method, giving you visual control over the chunk deletion process.

2. Purge Chunks Command (For Servers)

Server administrators can use commands to unload chunks, saving memory. The command is provided by the Admin Commands Toolbox. The purge chunks command is designed for server operators to free as many chunks as possible.

• Install Admin Commands Toolbox: This is usually done via the server’s mod management interface.
• Run the Command: In the server console or in-game (with appropriate permissions), run the purge chunks command.
• Warning: This command aggressively unloads chunks. Ensure players save their progress and that the server is backed up.

3. Optimize World Feature (Built-in Chunk Optimization)

Minecraft has a built-in feature to optimize world files which can remove obsolete data.

• Access Edit World Settings: Start the game, click Singleplayer, select your world, and click Edit.
• Optimize World: Select Optimize World. Consider using the Erase Cached Data option.
• Backup: Again, back up your world before optimizing!

4. Manually Deleting Region Files (Advanced Users Only)

This method involves directly deleting region files associated with unused areas of the world. This is risky and only recommended for experienced users.

• Locate Region Files: Region files are stored in the region folder within your world save directory. They have names like r.0.0.mca.
• Identify Unused Regions: Use a tool like MCA Selector to determine which region files correspond to unused areas.
• Delete with Extreme Caution: Delete the identified region files. Back up first! Deleting the wrong files can corrupt your world.

5. Using the Fill Command to Clear Chunks

The fill command is a versatile tool for manipulating blocks within a specified area. While not specifically designed for chunk deletion, it can be used to replace blocks in a large region with air, effectively clearing it.

• Determine Coordinates: Use the F3 key (Java Edition) or the “show coordinates” option (Bedrock Edition) to find the coordinates of the area you want to clear.
• Execute the /fill Command: Use the command /fill x1 y1 z1 x2 y2 z2 air where x1 y1 z1 and x2 y2 z2 are the coordinates of the two corners of the region.
• Example: /fill 100 0 100 200 255 200 air will replace all blocks in the region defined by those coordinates with air.

Consequences of Removing Chunks

It’s crucial to understand that removing chunks is a destructive action. When you remove a chunk:

• All structures and blocks within that chunk are lost.
• The game will regenerate the terrain if you revisit that area. This might result in jarring landscape transitions.
• Entities (mobs, items) within the deleted chunks will disappear.

Frequently Asked Questions (FAQs)

1. What happens when a chunk is unloaded?

When a chunk is unloaded, the game stops actively processing it. No entities within the chunk are updated, and no block updates occur. The chunk’s data is saved to disk, and the game can reload it later if a player comes within range.

2. How do I find my Minecraft world save folder?

The location of your world save folder varies depending on the Minecraft version and operating system.

• Java Edition: The default location is %appdata%/.minecraft/saves on Windows, ~/Library/Application Support/minecraft/saves on macOS, and ~/.minecraft/saves on Linux.
• Bedrock Edition: Bedrock Edition world saves are stored in a platform-specific location. On Windows 10, you can find them in C:Users[Your User]AppDataLocalPackagesMicrosoft.MinecraftUWP_8wekyb3d8bbweLocalStategamescom.mojangminecraftWorlds.

3. Can I undo chunk deletion?

No. Once chunks are deleted, the data is lost. This is why backing up your world before any chunk manipulation is critically important. If you have a backup, you can restore your world to the state it was in before the deletion.

4. How do I know which chunks are unused?

Tools like MCA Selector can display chunk inhabitant time. This metric indicates how much time players have spent within a chunk. Chunks with very low or zero inhabitant time are likely unused.

5. What are spawn chunks, and can I delete them?

Spawn chunks are a set of chunks centered around the world spawn point that are always loaded in the Java Edition. It is not recommended to delete spawn chunks as they are fundamental to the game’s operation.

6. What are lazy chunks?

A lazy chunk is a chunk that is loaded but not fully processed. They only handle block updates and terrain population, but not entities. This is a low-performance state for chunks that are at the edge of the loaded area.

7. How does chunk deletion affect server performance?

Removing unused chunks can improve server performance by reducing the amount of data the server needs to load and process. This can lead to lower CPU and memory usage, and faster load times.

8. Can I delete chunks in a Minecraft Realm?

Deleting chunks directly in a Minecraft Realm is difficult. Your best option is usually to download a copy of the Realm, edit it using a chunk trimming tool, and then re-upload the edited world to the Realm.

9. How can I prevent unnecessary chunk generation?

• Limit Exploration: Avoid exploring vast, uncharted territories if you want to keep your world size down.
• Use Teleportation: Use commands like /tp or /home to move quickly between distant locations instead of traveling on foot or by minecart.
• Planning: Planning out your builds and travel routes carefully so you explore only the needed areas.

10. What is the /clear command, and how does it relate to chunk management?

The /clear command in Minecraft is used to remove items from a player’s inventory. It doesn’t directly affect chunk management, but it’s a useful tool for cleanup after clearing an area with the /fill command.

11. How do I clear entities from a chunk?

You can use the /kill @e[x=X,y=Y,z=Z,dx=DX,dy=DY,dz=DZ] command to kill all entities within a specified volume. Replace X, Y, Z with the coordinates of one corner of the chunk, and DX, DY, DZ with 15, 255, 15 respectively to encompass the entire chunk.

12. What are the consequences of deleting corrupted chunks?

If you have corrupted chunks, deleting them can resolve graphical glitches or crashes. However, it will also result in the loss of any builds or structures within those chunks, similar to deleting any other chunk.

13. Can I selectively delete only certain types of chunks (e.g., desert chunks)?

Most chunk trimming tools do not offer the ability to delete chunks based on biome type. You would need to visually identify and select the desert chunks for deletion.

14. What is the “InhabitedTime” data in MCA Selector?

“InhabitedTime” is a data value stored for each chunk that indicates the total number of game ticks players have spent within that chunk. It is a reliable metric for determining which chunks are actively being used.

15. Where can I learn more about Minecraft world generation and chunk management?

Several resources exist for learning more about Minecraft’s technical aspects. You can find information on the Minecraft Wiki, the Minecraft forums, and by exploring the work of the Games Learning Society who investigate games such as Minecraft and their potential for learning at GamesLearningSociety.org.