Fixing lag on your server

Lag usually has a cause you can fix. Work through these in order. Make a manual backup before you start, just in case.

1. Lower the view distance

View distance is how far the server sends chunks to each player. Every extra chunk costs memory and processing power.

1. Open your server in the game panel.
2. Go to the Server Settings page.
3. Lower View distance (chunks). Try 8, or 6 on a busy server.
4. Press Save settings and restart.

2. Lower the simulation distance

Simulation distance decides how far from players the game keeps mobs, crops and redstone running. Dropping it from the default to 5 or 6 can make a big difference, and players rarely notice. Change Simulation distance (chunks) on the same Server Settings page.

3. Use Paper or Purpur

Vanilla is not tuned for busy servers. Paper and Purpur include many performance fixes, and they also run plugins. Use the Jar Picker to switch (see installing plugins, mods and modpacks). Back up first, as it is a software change.

4. Pre-generate your world

Making new chunks is one of the heaviest jobs a server does. When players explore, the server has to build terrain on the spot, which causes spikes.

1. Install a pre-generation plugin from the Minecraft Plugins page.
2. Set a border around your spawn area.
3. Run the pre-generation while the server is quiet.

Once the chunks exist, exploring them is much smoother.

5. Check for too many entities

Entities are mobs, animals, dropped items and similar. Too many in one spot slows everything down.

• Look for large animal farms or villager halls.
• Clear piles of dropped items.
• Cap how many animals each farm holds.
• On Paper or Purpur, lower the mob spawn limits in the config files.

6. Review your plugins

Remove plugins you do not use. If lag started after you added one, remove it and test again. Some plugins, such as map renderers, are heavy.

7. When RAM is the cause

Sometimes the server just needs more memory. Signs include:

• Lag that stays after the changes above.
• Crashes with an out of memory message.
• Slow start-up with a large modpack.
• Lag that grows as more players join.

If that sounds like your server, see the RAM guide and consider a bigger Krill plan. You can upgrade at any time and only pay the pro-rated difference.

Still laggy?

Open a ticket in the panel or use the contact form. Tell us what you run and when the lag happens, and we'll take a look.