Summary of the problem Loading Chunks Causing Server Lag Even After Generation Pack Version 1.3.3 What is the bug? I run a server for me and my friends. When I explore the world, it occasionally lags when generating chunks. Sometimes, I enter a chunk and the server continues to lag even after the chunk is generated, and after I leave the chunk. Even after rebooting the server, there is noticeable tick lag. Why is this an issue and what can I do to stop this from happening? Mod & Version Unmodified server installation. Link to log file Is it repeatable? Exploring the world, breaking blocks in explored chunks. Known Fix I solved the problem by editing the world in worldedit and deleting the chunks that initially caused lag.