HD uses more space

[woflux]

Hello, I formatted a 1 Tb HD with ext3 and it contains only a folder of 437 Gb but device properties shows 488 Gb are used, how are the other 50 Gb used ?

thank you

[xenopeek]

The file system also needs space for keeping track of where each file is, what it is called, who owns it, what its permissions are, and so on. That may explain the difference.

[woflux]

does it need 50 Gb to track 10000 files ?

[caf4926]

lost+found
It's used to store data recovered by fsck too, should that become necessary

[xenopeek]

device properties shows 488 Gb are used

Let's take a step back; in which application exactly are you seeing this?

And the space set aside for administrative purposes is fixed; meaning it needs the same amount of space even with zero files or with a million files. That is how the ext4 filesystem works, upon creation a portion of the disk is set aside for administrative purposes. That said, 5% does sound a bit much perhaps--on my 240 GB hard disk it is closer to 2%.

Some applications say they display GB and TB, when in fact they are showing GiB or TiB, which is a different unit and would mean a different amount of bytes. http://en.wikipedia.org/wiki/Byte#Unit_symbol

1 GiB = 1.07 GB
1 TiB = 1.1 TB

So for example when a hard disk manufacturer states he has a 1 TB hard disk, most applications will show that as 0.91 TiB. That is the same amount of bytes, but with a different notation. It's quite a difference, and may also here be clouding the figures you are looking at.

[eanfrid]

By default any partition formatted with ext2/3/4 reserves 5% of the capacity to the root user for admin tasks... 5% of 1000GiB are 50GiB

You can use

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sudo tune2fs -m N /dev/sdX

(where N is the % reserved to the root user and sdX is the partition to adjust). If it is only a data HDD, you can set the reserved space to 0% => for example:

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sudo tune2fs -m 0 /dev/sdb2

[xenopeek]

By default any partition formatted with ext2/3/4 reserves 5% of the capacity to the root user for admin tasks... 5% of 1000GiB are 50GiB

It wouldn't show that space as used though, it will show it as free disk space. It will just not let a normal user use that last 5% of disk space, only the root user can use it.

[caf4926]

By default any partition formatted with ext2/3/4 reserves 5% of the capacity to the root user for admin tasks... 5% of 1000GiB are 50GiB

It wouldn't show that space as used though, it will show it as free disk space. It will just not let a normal user use that last 5% of disk space, only the root user can use it.

I think it might
When I use Gparted and format an ext4 partition is shows used space and I'm sure that relates to lost+found

[eanfrid]

xenopeek: check "man tune2fs" regarding the "-m" option This space is reported as used (unavailable), even if it is empty, with df in a term, with gparted or with gnome-system-monitor (in GSM: compute "free space" minus "available space" while "used space" percentage is computed on what remains "available")

[xenopeek]

For my 80 GB hard disk, System Monitor is showing:
- 73.4 GiB total
- 63.9 GiB free
- 60.2 GiB available
- 9.5 GiB used
So total = free + used. df shows the available count matching this output, while GParted shows 63.9 GiB unused matching the free count here.

Three applications, two different ways to look at storage... So we are waiting for OP to tell us in which application this 488 Gb used is displayed

[woflux]

I open the HD with caja then right-click to properties

[eanfrid]

OK then you see (total) minus (reserved) minus (used-by-your-data) = (available) space

[woflux]

Can I remove admin reserved space if I use the HD only for data storing ?

[xenopeek]

Yup eanfrid already answered that above. For example the following command if your data partition is /dev/sdb1.

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sudo tune2fs -m 0 /dev/sdb1