<qandaentry>

        <question id="disk-more-than-full">

          <para>How is it possible for a partition to be more than 100%

            full?</para>

        </question>

        <answer>

          <para>A portion of each UFS partition (8%, by default) is

            reserved for use by the operating system and the root user. 

            <command>df</command> does not count that space when

            calculating the <literal>Capacity</literal> column, so it can

            exceed 100%.  Also, you'll notice that the

            <literal>Blocks</literal> column is always greater than the

            sum of the <literal>Used</literal> and

            <literal>Avail</literal> columns, usually by a factor of

            8%.</para>

          <para>For more details, look up the <option>-m</option> option

            in &man.tunefs.8;.</para>

        </answer>

      </qandaentry>