删除磁盘分区时保留给root用户的部分

原文章地址http://yegle.net/2008/01/05/use-the-reserved-blocks/
原创：一阁

磁盘分区时，home是一个单独的分区，第一次安装时也没经验，当时就保留了5％的空间给root用户。但实际上root用户的家目录是在/下，基本上不需要在home保留一部分空间给root了，所以有必要把这5%给去掉。

google了一下，发现是用tune2fs来调整这个reserved-blocks的。

sudo tune2fs -m 0 /dev/sda5

其中m参数指定的是reserved-blocks占总大小的百分比。

man手册中相关内容：
-m reserved-blocks-percentage
Set the percentage of the filesystem which may only be allocated by privi-
leged processes. Reserving some number of filesystem blocks for use by
privileged processes is done to avoid filesystem fragmentation, and to
allow system daemons, such as syslogd(8), to continue to function cor-
rectly after non-privileged processes are prevented from writing to the
filesystem. Normally, the default percentage of reserved blocks is 5%.