Server crashing after a schematic
Big pastes hang or kill a server. Split them, use FastAsyncWorldEdit, and give the server room.
What you are looking at
You run the paste and the server stops responding — players time out, the console goes quiet, and either it recovers after a long pause or the watchdog kills it. The log often mentions a tick taking too long, or memory.
Why it happens
Plain WorldEdit does the whole paste inside a single server tick. A tick is meant to last fifty milliseconds; placing a few million blocks takes far longer, and the server's own watchdog decides the server has frozen and shuts it down. Nothing is broken — it was simply asked to do a week's work between two heartbeats.
What to do
- 1Install FastAsyncWorldEdit and paste with that instead. It spreads the work across many ticks and is the single biggest improvement you can make.
- 2Give the server more memory before a large paste, and make sure it is not already close to its limit.
- 3Raise or disable the watchdog timeout in server.properties while you do the paste, then put it back. Leaving it off permanently hides real freezes later.
- 4Paste with no players online. Every player online is more work per tick and less headroom.
- 5For a genuinely huge build, paste it in sections rather than in one command.
Entities are heavier than blocks. A build carrying hundreds of item frames, armour stands or paintings can crash a server that would have handled the same volume of plain blocks without noticing.