How to Optimize a Minecraft Server and Fix Low TPS

Lag on a Minecraft server almost always shows up as low TPS. Here is how to measure it, find what is causing it, and get your server running smoothly again.

When a Minecraft server lags, the real measure is TPS, ticks per second. A healthy server runs at 20 TPS. If it drops, everything slows: mobs, redstone, movement. Here is how to diagnose and fix low TPS.

1. Measure it

Run /tps in-game (available on Paper and most server software). It shows your average TPS over the last 1, 5, and 15 minutes. Anything consistently below about 19 means something is wrong.

2. Profile the lag

Do not guess, profile. Paper includes the spark profiler (/spark profiler) which tells you exactly what is eating your tick time: a plugin, entity processing, chunk loading, or world generation. This one step saves hours of trial and error.

3. Common causes and fixes

Too many entities. Mob farms and dropped items pile up. Cap mob spawns and clear ground items periodically.
View distance too high. Lowering view-distance and simulation-distance in server.properties and Paper config is the single biggest easy win.
A heavy plugin. spark will name it. Update it, reconfigure it, or replace it.
Chunk loading and world gen. Pre-generating your world with a plugin stops the lag spikes that come from generating new chunks as players explore.
Redstone and hoppers. Large contraptions and hopper arrays are expensive; Paper config lets you tune hopper behaviour.

4. Tune your Paper config

Paper exposes powerful optimisation settings: mob spawn limits, entity activation ranges, tick rates for various systems. Sensible tuning here can recover a lot of TPS without changing gameplay noticeably.

5. Allocate RAM correctly

More RAM is not always better: over-allocating can cause garbage-collection pauses. Allocate what your server needs (based on player count and plugins) and use good startup flags (Aikar flags are the community standard) rather than maxing it out blindly.

The quick checklist

/tps to measure, /spark profiler to find the cause.
Lower view and simulation distance.
Control entities and pre-generate the world.
Tune Paper config; update or replace heavy plugins.
Allocate RAM sensibly with proper flags.

Start from a solid base

A well-configured setup and good plugins prevent most lag before it starts. Browse optimised, properly-supported Minecraft plugins and complete server setups on ModForge, every purchase is protected, so you know what you are getting.