Disk space used after initial partition is created

Wraezor · 04-20-2005, 04:50 PM

Hey folks,

I'm working on a RAID 0 array right now, and just wondering if anyone can give me any details as to why roughly 1% of the disk space is used immediately after formatting.

See the following:

Code:

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda              2.8T  121M  2.6T   1% /u01

or more specifically:

Code:

# df -m
Filesystem           1M-blocks      Used Available Use% Mounted on
/dev/sda               2860619       121   2717455   1% /u01

Now, 121MB is not 1% of 2.8TB. It should be closer to 28GB for that. I realize it's rounded up. Still 121 MB is a lot of space.

Even weirder is if I browse through a Samba share to this partition. I get the following details in the Explorer panel:

Capacity: 2.72 TB
Used: 139 GB
Free: 2.59 TB

Which is a whole lot more than 1%. That's more like 5%.

I'm not really concerned with what Windows is reporting, as long as the proper amount of storage is actually available. Can anyone provide insight into what requires 121MB of space on an empty drive?

It was formatted with mkfs.ext3 -Tlargefile4 /dev/sda

Thanks a lot.

michaelk · 04-20-2005, 10:36 PM

When an ext3 filesystem is created 5% (usual default value) is reserved for root use. This is supposed to keep fragmentation down as well as provide root space for filesystem maintenance. You can use tune2fs to change the value.

Wraezor · 04-21-2005, 10:01 AM

Awesome, thanks. I tuned it down to 2%, which I think should be plenty, seeing as how there's nothing but data files on here....no system files.

Appreciate the help.