1、查看保留空间大小 tune2fs -l /dev/sda8 reserved blocks2、调整保留空间大小(系统默认5%) tune2fs -m 0.5 /dev/sda8参考链接:https://askubuntu.com/questions/249387/df-h-used-space-avail-free-space-is-less-than-the-total-size-of-home