Partition size problem

[devil_ankur18]

this is the output df -H of my ubuntu 8.10 desktop

root@cc-desktop:~# df -H
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 20G 8.2G 11G 44% /
tmpfs 1.1G 0 1.1G 0% /lib/init/rw
varrun 1.1G 558k 1.1G 1% /var/run
varlock 1.1G 0 1.1G 0% /var/lock
udev 1.1G 2.9M 1.1G 1% /dev
tmpfs 1.1G 13k 1.1G 1% /dev/shm
lrm 1.1G 2.1M 1.1G 1% /lib/modules/2.6.27-14-generic/volatile
/dev/sda6 109G 93G 11G 90% /downlaod
/dev/sda7 26G 17G 8.9G 66% /windows



check out the entry for /dev/sda6 , its used(93) + Available(11) < Size(109)

Where is 6 GB gone :confused:

please help me out

[skymera]

Well /dev/sda6 is mounted on /downlaod

Go have a look what's taking up the space.

[tomcheng76]

post your "fdisk -l" and "free -m"

[kpkeerthi]

5% of the drive's total space is reserved for the super-user (root) so that the operating system can still write to the disk even if it is full.

[unutbu]

ext2/ext3/ext4 filesystems have "reserved blocks". This is space that is reserved for root to use. It is counted as part of the total size of the filesystem, but it is not counted as part of the amount "Used" or "Available".

The default amount of reserved space is 5%.
5% of 109G is 5.45G.
109-(93+11) = 5G.

If you use "df" instead of "df -H" I think the discrepancy will be smaller.

You can change the amount of reserved space on an ext* filesystem



sudo tune2fs -m1 /dev/sda6 # Set reserved blocks to 1% of total space

sudo tune2fs -r51207 /dev/sda6 # Set reserved blocks to 51207 4K-blocks* = 200 MiB

*For a 109G filesystem, the default block size is 4 KiB per block. To find out the block size on sda6, run

sudo tune2fs -l /dev/sda6 | grep "Block size"

[KIAaze]

Hehe, I noticed a similar problem recently: http://ubuntuforums.org/showthread.php?t=1145503

Just found this, but haven't checked if it explains the exact number of space I had used (5% from 10GB would have been about 512 MB for me):
http://www.walkernews.net/2007/07/13/df-and-du-command-show-different-used-disk-space/
http://www.chineselinuxuniversity.net/articles/17988.shtml
http://books.google.com/books?id=wOGUuoHUyAEC&pg=PA47&lpg=PA47&dq=linux+df+used+%2B+available+does+not+equal+size&source=bl&ots=OEkupul51V&sig=YMNmKvRjl2xoeoJbjXj5rfbeR7I&hl=en&ei=82kBSoXvCMGOsAaVwej0Dg&sa=X&oi=book_result&ct=result&resnum=1#PPA48,M1

[devil_ankur18]

post your "fdisk -l" and "free -m"


root@cc-desktop:~# fdisk -l

Disk /dev/sda: 160.0 GB, 160041885696 bytes
255 heads, 63 sectors/track, 19457 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xf5e1f5e1

Device Boot Start End Blocks Id System
/dev/sda1 * 1 2437 19575171 83 Linux
/dev/sda2 2438 19457 136713150 5 Extended
/dev/sda5 2438 2952 4136706 82 Linux swap / Solaris
/dev/sda6 2953 16325 107418591 83 Linux
/dev/sda7 16326 19457 25157758+ b W95 FAT32

root@cc-desktop:~# free -m
total used free shared buffers cached
Mem: 1979 1930 48 0 15 1260
-/+ buffers/cache: 654 1324
Swap: 4039 4 4034

[devil_ankur18]

ext2/ext3/ext4 filesystems have "reserved blocks". This is space that is reserved for root to use. It is counted as part of the total size of the filesystem, but it is not counted as part of the amount "Used" or "Available".

The default amount of reserved space is 5%.
5% of 109G is 5.45G.
109-(93+11) = 5G.

If you use "df" instead of "df -H" I think the discrepancy will be smaller.

You can change the amount of reserved space on an ext* filesystem



sudo tune2fs -m1 /dev/sda6 # Set reserved blocks to 1% of total space

sudo tune2fs -r51207 /dev/sda6 # Set reserved blocks to 51207 4K-blocks* = 200 MiB*For a 109G filesystem, the default block size is 4 KiB per block. To find out the block size on sda6, run

sudo tune2fs -l /dev/sda6 | grep "Block size"

Thanx , it works :guitar:
I use


tune2fs -m0.8 /dev/sda6Now output of df -H is


Filesystem Size Used Avail Use% Mounted on
/dev/sda1 20G 8.2G 11G 44% /
tmpfs 1.1G 0 1.1G 0% /lib/init/rw
varrun 1.1G 558k 1.1G 1% /var/run
varlock 1.1G 0 1.1G 0% /var/lock
udev 1.1G 2.9M 1.1G 1% /dev
tmpfs 1.1G 13k 1.1G 1% /dev/shm
lrm 1.1G 2.1M 1.1G 1% /lib/modules/2.6.27-14-generic/volatile
/dev/sda6 109G 93G 16G 86% /downlaod
/dev/sda7 26G 17G 8.9G 66% /windows