Direct answer
Capture spark while the suspected contraption is loaded and running. If block ticks, neighbor updates, pistons, redstone wire calculations, or a related plugin/mod dominates, identify the chunk/area and reproduce with that machine on and off.
Why redstone can be expensive
High-frequency clocks and large update chains can trigger many block and shape updates in a single tick. The cost may also come from the system around the redstone: hoppers, minecarts, mobs, fluids, TNT, or plugins reacting to block events.
Paper redstone implementations
Paper currently offers Vanilla, Eigencraft, and Alternate Current redstone implementations. Paper notes that alternative implementations can reduce redstone-dust cost, but they can also change redstone behavior. Test technical builds before changing the implementation on an established survival server.
Find loaded problem areas
A redstone machine generally cannot consume server tick time when its chunks are not ticking. If lag begins only when a player enters an area, compare a profile before and after that area becomes active.
Prefer fixing the machine
When possible, remove unnecessary always-on clocks, batch operations, stop machines when outputs are full, and keep automation from running when nobody needs it. This preserves more predictable mechanics than broad server-wide nerfs.
References
These sources were checked while preparing this article. Performance behavior and configuration can change between Minecraft/server-software versions, so verify version-specific settings before applying them.
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