Infinite Tick Loop

The server detects that it is stuck repeating work without progressing, a tick loop. Something, usually a plugin/mod or a redstone/entity interaction, keeps the tick from completing.

What does this error mean?
A 'tick loop detected' warning means the server's main loop appears stuck cycling without advancing, a sign of an infinite loop in code or a self-perpetuating in-game interaction that never resolves.
Tick loop detected
Most Common Causes
  • An infinite loop in a plugin/mod.
  • A self-triggering redstone or entity interaction.
  • Recursive event handling that never stops.
  • A scheduler firing faster than it completes.
  • A datapack function looping without a base case.
How To Diagnose
  1. Read any stack/thread dump for the looping code.
  2. Note what was happening just before the warning.
  3. Use spark to capture the long/looping tick.
  4. Isolate suspect plugins/mods or contraptions.
Recommended Fixes
  • Fix the looping code
    Update or remove the plugin/mod whose code is looping.
  • Break the in-game loop
    Disable the redstone/entity setup that keeps re-triggering.
  • Fix recursive functions
    Add a base case/limit to datapack functions that recurse.
  • Profile to confirm
    Use spark to verify the loop is gone after changes.
Frequently Asked Questions

Related, a tight loop can freeze the tick and may trip the Watchdog if it never ends.

Thread dumps and spark profiles show what the main thread keeps executing.

Yes, a self-feeding contraption can create an in-game loop the server cannot resolve.