More RAM did not fix the lag

I upgraded RAM but the server still lags.

RAM only helps if memory was the limit; most lag is CPU work in the main thread, which needs the causes fixed.

Before you start: spark installed.

Step by step

1. Profile with spark while it lags (see the lag guide) to see what is really slow.
2. Reduce entities, farms and redstone, and pre-generate the world.
3. Lower simulation-distance in Quick Settings to 6 so less of the world is active.
4. Use Paper/Purpur and keep plugins updated.
5. Check that the server was restarted after the upgrade so Java uses the new memory.
6. Compare Statistics before and after: if memory never went near the old limit, RAM was never the bottleneck and CPU work is.

Check it worked: TPS improves after fixing the causes spark showed.

Why it happens: Minecraft's main loop is mostly single-threaded, so entities, farms and chunk generation lag regardless of RAM.

More guides on RAM, CPU, performance, and lag:

• Find out why your server lags
• Out of memory errors
• RAM always shows high in the panel
• High CPU usage
• Too many entities, mob farms and item build-ups
• Redstone and hopper lag