Server Despawn Radius

     ambient:
       hard: 128
       soft: 32
‍
     axolotls:
       hard: 128
       soft: 32
‍
     creature:
       hard: 128
       soft: 32
‍
     misc:
       hard: 128
       soft: 32
‍
     monster:
       hard: 128
       soft: 32
‍
     underground_water_creature:
       hard: 128
       soft: 32
‍
     water_ambient:
       hard: 64
       soft: 32
‍
     water_creature:
       hard: 128
       soft: 32

These options will change the distance away from players where mobs will start to despawn. "hard" will depsawn the mobs instantly, while "soft" will start a periodic check and randomly despawn the mobs at intervals.