Software
How to Find Lag With spark on Your Minecraft Server
spark shows what the server spends its time on, so you can find the farm, plugin or mod behind lag instead of guessing.
Get spark
Recent Paper versions include spark already. Type spark tps in Console; if it answers, you are set. Otherwise add it on Mods → Plugins (or Mods → Mods on a modded world) and apply.
Commands
Type in Console, without a slash:
spark tpsshows ticks per second and tick times. 20 TPS is full speed.spark healthshows memory and CPU.spark profiler start, wait a few minutes while people play, thenspark profiler stop. It prints a link to a report.
Reading the report
Open the link and expand the biggest entries. Entity ticking points to mobs or farms, chunk generation points to exploring (see Chunky), and a plugin or mod name points to that plugin or mod.
Plugins run on Village and Kingdom with Paper or Purpur. Compare plans on the plans page.