I used the locate command to find a structure and the structure could not be found. The game started to lag from there on out. Then I tried looking for a different structure 5-10 seconds later, and the lag got worse, and nothing came up for this structure. I did one last structure, and my game was border-lining freezing out, so I clicked the exit and save button on the main menu, and the game just couldn't keep up and crashed.
MC-126244 '/locate', explorer maps, and treasure maps can cause extreme TPS lag, even leading to a complete server freeze if structure generation is turned off