This plugin allows you to define chunks to keep in memory, AND loads them when the server boots up. Tested for Bukkit/spitgot 1.8.8-1.15
/keepchunk
Stores the X/Z of the chunk that you are standing on into the config.yml. This is supported across many worlds. This does not work from console
Permission:
antichunkunload.keepchunk
Created for:
DiamCraft Factions