ServerCore

ServerCore

A mod that aims to optimize the minecraft server.\
Works on both dedicated servers and singleplayer!

This includes:
- Several patches & optimizations to improve performance and reduce lagspikes, which shouldn't make any noticeable changes during gameplay.
- Many configurable features that can heavily reduce lag, but have a slight impact on gameplay depending on the configuration.

Be advised
By default, ServerCore should not alter vanilla behavior. Features that do are disabled by default.
It is advised to configure this mod to your own requirements for the best balance between speed and behavior.

Features

Optimizations

A lot of the optimizations in this mod are focused on getting rid of the majority of random lagspikes on servers.\
Other than that, it also includes plenty of optimizations for things like chunk ticking, mob spawning, item frames and
player logins.

Entity Activation Range

A very configurable feature that allows you to drastically cut down on the amount of entities that have to be processed
on the server.\
This is a port based off of Spigot's and PaperMC's implementation, but more configurable with additional (optional) features.

Dynamic performance checks

Allows the server to automatically adjust the current settings depending on the tick time and config.\
These include: Chunk-tick distance, View distance, Simulation distance & Mobcaps.

Villager lobotomization

Allows the server to cut down on villager lag from large trading halls, by making villagers stuck inside 1x1 spaces tick less often.

More configurable mobspawning

Allows you to modify the spawnrate and vanilla mobcaps of each individual spawngroup.
It also provides optional functionality to force mobcaps to apply to zombie reinforcements, spawners and nether portal randomticks.

Breeding Caps

A feature that allows you to set a cap on the amount of mobs of the same type that can be bred within a certain radius.\
This can be useful to prevent players from breeding thousands of animals like chickens or cows in a small area.

Chunk ticking distance

A setting that allows you to reduce the distance at which chunks can tick (mob spawns & random ticks).
\
\
- And more!

Commands, Placeholders and Configuration

Commands
- /servercore reload - Reloads the configuration file.
- /servercore settings - Allows for modifying dynamic settings ingame.
- /servercore status - Gives information about the current dynamic settings.
- /mobcaps - Displays current per-player mobcaps for each spawn group.
- /statistics entities | block-entities - Displays performance related statistics.

Placeholders
- %servercore:view_distance% - The current view distance.
- %servercore:simulation_distance% - The current simulation distance.
- %servercore:chunk_tick_distance% - The current chunk tick distance.
- %servercore:mobcap_percentage% - The global mobcap percentage that is currently being used.
- %servercore:chunk_count% - The amount of chunks on the server (doesn't have to be fully loaded).
- %servercore:chunk_count loaded% - The amount of fully loaded chunks on the server (expensive).
- %servercore:entity_count% - The amount of loaded entities on the server.
- %servercore:entity_count nearby% - The amount of loaded entities nearby.
- %servercore:block_entity_count% - The amount of ticking block entities on the server.
- %servercore:block_entity_count nearby% - The amount of ticking block entities nearby.

Configuration

By default, ServerCore will disable most of its changes that can affect vanilla behavior.\
This way you can safely install the mod without having to worry about breaking things.

However, if you want to squeeze out the most performance, these default settings might not be enough.\
To change these settings you can edit config.yml and optimizations.yml in the config/servercore folder.

You can find some example configurations here.

License

ServerCore contains several ports based on patches from repositories such as PaperMC, Purpur and Airplane.\
If a file uses the GPL-3.0 license it will be stated at the top. All other files are licensed under MIT.

ABOUT THIS LISTING

This page describes ServerCore by Wesley1808. The description and screenshots are the author's own, imported from their listing on Modrinth on 26 October 2026: https://modrinth.com/mod/servercore

Mythiq.net hosts no files for it. The download button goes straight to the release file on cdn.modrinth.com, so you are downloading from the author's own host, not from a copy of ours.

The download count, rating and comments on this page start at zero and count Mythiq.net only. The source's own figures are not copied here — they measure a different site, and a number that cannot be checked against our own ledger is not worth printing.

MOD LOADER

This release is built for Fabric. A mod built for one loader will not load under another — Fabric mods do not run on Forge, and vice versa.

GAME VERSION

Built for Minecraft 26.3. Minecraft mods are tied to an exact version: a 1.21.4 build will refuse to load on 1.21.5.

DEPENDENCIES

Check the author's listing for required libraries before you start the game — a missing dependency shows up as a crash on launch, not as a warning.

1. Install Fabric for the Minecraft version you play, if you have not already.

2. Download the .jar with the button on this page. Do not unzip it — a mod jar is installed as it is.

3. Put it in your mods folder:

Windows — %APPDATA%\.minecraft\mods

macOS — ~/Library/Application Support/minecraft/mods

Linux — ~/.minecraft/mods

4. Launch the game with the Fabric profile selected.

ON A SERVER

Anything that changes world generation or gameplay has to be installed on the server as well as on every client. Client-side visual and interface mods do not.

UPDATING

Replace the old .jar rather than adding the new one beside it. Two versions of the same mod in the folder is a crash on launch.