Dropped items are entities. Hoppers check for them constantly. Put a few thousand of each in one place — which is exactly what a storage room is — and you have a performance problem built out of blocks nobody thinks of as expensive.
What you are seeing
- TPS drops near one player's base and recovers when they leave.
- A profiler showing significant time in hopper or item-entity ticking.
- Thousands of dropped items in one chunk after a mob farm overflows.
- A furnace or sorting array that visibly slows down when full.
Three fixes, cheapest first
| Fix | Where | Effect |
|---|---|---|
merge-radius | spigot.yml | Items and experience stack together sooner, so fewer entities exist. |
disable-move-event | paper-world-defaults.yml | Hoppers stop firing a plugin event on every single item movement. |
alt-item-despawn-rate | paper-world-defaults.yml | Lets cobblestone and other junk despawn faster than valuable items. |
Why hoppers are expensive
A hopper checks the container above it and the one it feeds, every tick, whether or not anything is moving. A hundred hoppers in a sorting system is a hundred checks twenty times a second, and that cost is paid even when the system is idle and every chest is full.
Long hopper chains for transport can usually be replaced by a water stream or a single drop into a collection point. The items arrive the same way; the ticking cost goes from dozens of blocks to one.
Items despawn after five minutes by default, and players rely on that being long enough to run back after dying. Shortening it for everything turns a performance tweak into lost inventories. Use the alternate rate for junk instead.
Standing in the storage room, TPS stays at 20, and a spark report no longer shows hopper ticking near the top.