Minecraft
Is my lag from CPU, RAM, ping, mods, or plugins — how do I tell?
"Lag" can mean several very different problems, and the fix depends entirely on which one you have. A quick look at how the lag shows up usually tells you where to look first.
Quick triage
- Everyone lags at once, blocks break slowly, mobs freeze → server-side lag (low TPS), usually CPU or a heavy mod/plugin. Run spark or timings.
- Only far-away players lag, hits register late → ping (network distance). Fixed by choosing the region nearer your players.
- Crashes or restarts every few hours → likely RAM (OutOfMemory). Check the Console.
- Started right after adding something → that mod or plugin is the prime suspect.
Confirming the cause
- Use a spark report to separate CPU load from a specific plugin — it shows the biggest consumers by name.
- Watch RAM in the Console during load to catch memory issues (look for OutOfMemory).
- If TPS is a healthy 20 but you still feel delay, it's ping, not server lag.
Tip: Match the symptom to the category before changing anything — upgrading RAM won't help a CPU-bound server, and a faster CPU won't fix ping.
Frequently asked questions
How do I know it's ping and not the server? If your TPS is fine (around 20) but actions feel delayed, and it only affects far-away players, it's ping — network distance to your region.
What if several of these seem true at once? Start with a spark report to rule CPU and plugins in or out, then watch RAM in the Console. If you're stuck, paste the spark link in a ticket and we'll help sort it out.