Minecraft wiki entry for Ramdisk_enabled_server, associated text: In a Minecraft server, one of the strongest bottlenecks are disk I/O related operations (e.g. chunk management). By moving the data into the RAM, access times are near instant and data transfer rates become significantly faster, making chunk loading and saving much faster operations. Since a Minecraft world currently consists of very many chunk files, seek time is equally, if not more, important for overall speed.