Missing MB on a GPT partioned SSD

I recently installed Arch Linux on an Intel 40GB SSD. I used GPT for partioning (via GNU parted) and created the following partions:

• /dev/sda1: 1 MB, no FS, flag=bios_grub
• /dev/sda2: 30MB, /boot, ext2, flag=boot
• /dev/sda3: 20GB, /home, ext4
• /dev/sda4: ~20GB, /, ext4

After struggling to install grub2 from the livecd environment (which I finally did via grub-install /dev/sda --root-directory=/mnt/ --no-floppy --force) I got a working system.

However, when I was inspecting disk usage with df I noticed that my home partition had around 170MB of used space on it. This surprised me because the only things on /home were one users.bashrc,.bash_history, and.lesshst. du confirmed that there was only a few KB of space being used on /home.

Почему df report approximately 170MB being used when du не? Is this space "gone forever", or can I regain it by repartioning and/or reinstalling?

Когда я установил grub2, он сказал что-то вроде "ваша область вставки слишком мала", и что я мог "использовать BLOCKLISTS, но BLOCKLISTS НЕ НАДЕЖНЫ". В конце концов, единственный способ получить загрузку системы с SSD - это использовать списки блоков с помощью флага grub-install --force. Связано ли это с таинственным отсутствием 170 МБ?

Спасибо