The Killd Board / Hoppers
How many hoppers does it take to crash a Minecraft server?
528,397 before the tick rate moved at all, and it never died. We stopped at 2,020,740 hoppers with the server still standing. That is more than fifty times the next-highest number on the board and the most surprising result of the series.
Paper 1.21.11 · AMD Ryzen 7 9700X · 6GB allocated
Why hoppers cost so much
Hoppers have a reputation from a decade ago that modern Paper has largely fixed. An idle hopper with nothing above it and nowhere to push does very little: the scan is cheap and the server skips most of the work when there is nothing to move. The reputation belongs to hoppers that are actually shifting items, and especially to hopper minecarts, which cost roughly 120 times more per unit on this same board.
How we tested it
Everything spawned into a single chunk, in one pile, with the server left running until the tick rate gave up. The server ran Paper 1.21.11 on an AMD Ryzen 7 9700X with 6GB allocated, which is the same hardware and the same RAM policy as an ordinary Hostd plan. We watched TPS and tick times rather than guessing, wrote down the count where the server first fell behind, and kept spawning until it either died or made it clear it was not going to.
If someone tells you to rip out your hoppers to fix TPS, ask what the hoppers are doing. Idle ones are not your problem. Chains actively moving items, and hopper minecarts, are a different story.
What this means for your server
If your own server is printing Can't keep up! Is the server overloaded? the cause is the same shape as this one: something in the tick loop is taking longer than its 50ms budget. Roastd reads your RAM allocation, view distance, player slots, JVM flags and logs and names which of those it is. No account, no world upload, no charge.
Questions about hoppers
Do hoppers cause lag in Minecraft?
Far less than their reputation suggests, at least on modern Paper. It took 528,397 idle block hoppers before our test server fell behind, and over two million before we gave up trying to kill it. Hoppers actively moving items cost more, and hopper minecarts cost dramatically more.
How many hoppers can a Minecraft server handle?
On Paper 1.21 with idle hoppers, more than you will ever build. Our run passed two million without the server dying. The practical limit on a real server is set by how many of them are moving items at once, not by how many exist.
Elsewhere on the board
Keep reading
Rent the machine we keep breaking
Same AMD Ryzen 7 9700X, same hard-reserved RAM, same NVMe. Yours will not have 2,020,740 hoppers in one chunk, which gives it a considerable head start. Online in under a minute, with a free address, DDoS protection and a 7-day money-back guarantee.