Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Possible Duplicate:
ext4: How to account for the filesystem space?

After googleing a little I find that ext4 reserve 5% for root: Reserved space for root on a filesystem - why?, ext2/3/4 reserved blocks percentage purpose. And if I use tune2fs to set the number of reserved blocks to 0, it will take them back. But I use that code on a 100MB volume and get half of the reserving space, it was 10.5MB, and after setting to 0 the used space became 5.5MB. Why is the used space still not zero?

I used the following command to set the reserved space:

tune2fs -m 0 /dev/mapper/truecrypt1
share|improve this question

marked as duplicate by Gilles, jasonwryan, Mat, Caleb, Chris Down Nov 17 '12 at 23:36

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

What command did you use to view the reserved space? Remember ext4 needs some room to live in, too. You may want to try /sbin/tune2fs -l /dev/mapper/truecrypt1 and look at the Reserved block count line. – Michael Kjörling Nov 16 '12 at 9:24
up vote 0 down vote accepted

There is still space required for the filesystem's internal usage (superblocks, etc). This is merely the way ext4 works and defines "used space".

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.