FixMySpawnR
by Team Jackdaw
FixMySpawnR pauses mob spawners that stay active without any player nearby, so the server stops spending time on spawning logic for them.
What it does
A mob spawner keeps running spawning logic even when nothing is there to use it, and bunches of mods add dungeons, caves and other structures full of them, which strains the server tick. FixMySpawnR adds a deadlock timer that detects spawners that have gone unused and deactivates them, freeing computing time for other server logic. The author reports that the timer reduces tick load by about half on a test world, with average tick time dropping from around 20 milliseconds to 10 in a cube of spawners.
The timer is configured in a server-sided configuration file, and its base value is one game day, 24,000 ticks. A spawner can be reactivated by applying a redstone signal to it, and the author recommends placing a redstone dust line or a lever on top of it, because those sources emit the least light and occupy the least space. The mod runs on Fabric and NeoForge for 1.21.11 and is open source under the GNU General Public License v3.0 only. Source code is public.
Key features
Deadlock timer
Spawners that stay unused past a set time are deactivated, so their spawning logic no longer runs each tick.
Redstone reactivation
A redstone signal of level 8 or higher placed on or beside a spawner lets it resume normal operation.
Server-sided configuration
The timer length is set in a server configuration file, with a base of 24,000 ticks, one game day.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Heavy spawner-filled worlds
Servers running large dungeon or cave packs can cut the tick load that idle spawners add.
Mob farms with lever control
Players who run farms can keep a spawner active with a lever or redstone line, while idle ones are paused.
Who it’s for: Server owners running modpacks with many spawners will get the most from FixMySpawnR. Players who run single-player worlds with only a few spawners are unlikely to notice a change.
Questions
Does FixMySpawnR need to be installed on both sides?
Which loaders does FixMySpawnR support?
How does a player keep a spawner running?
More from Team Jackdaw
What the author says
FixMySpawnR Claims to reduce about half of the tps lag caused by mobspawners. A bunch of mods add dungeons and caves and fun stuff with mobspawners in them, but mobspawners are pretty heavy on server logic. they scan a big area for players and for spots to spawn mobs in. if players load these spawners in the chunks…
Official listing
- Modrinth page
- modrinth.com/mod/fixmyspawnr
- Owner
- Team Jackdaw
- Published
- 2026-01-10
- Updated on Modrinth
- 2026-01-11
- Facts verified
- 2026-10-15