NTFS -> EXT4 migration, where did 120 GB go?

Question

wim@wim-ubuntu:~/Desktop$ mount | grep media
/dev/sdc1 on /media/data type ext4 (rw,nosuid,nodev,uhelper=udisks)
/dev/sdb1 on /media/wd type fuseblk (rw,nosuid,nodev,allow_other,blksize=4096,default_permissions)
wim@wim-ubuntu:~/Desktop$ df | grep media
/dev/sdc1            1922858352 1824822680    360072 100% /media/data
/dev/sdb1            1953512000 1825392384 128119616  94% /media/wd
wim@wim-ubuntu:~/Desktop$ df -h | grep media
/dev/sdc1             1.8T  1.7T  352M 100% /media/data
/dev/sdb1             1.9T  1.8T  123G  94% /media/wd

I am moving my data from an NTFS drive to an ext4 drive. On the NTFS volume I had 122.2 GB free, then after copying with rsync (excluding a couple of unneeded NTFS files in System Volume Information), I have only 351.6 MB free.

The hard disks are identical WD 2TB drives. I created the EXT4 partition with gparted, is there any reason why the ext4 would have 30653648 less blocks on it?

Output of sudo fdisk -l:

Disk /dev/sdc: 2000.4 GB, 2000397852160 bytes
255 heads, 63 sectors/track, 243201 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00bb4cbc

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1      243201  1953512001   83  Linux

Disk /dev/sdb: 2000.4 GB, 2000397852160 bytes
255 heads, 63 sectors/track, 243201 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xcefa6110

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1      243201  1953512001    7  HPFS/NTFS

Answer 1

After some fiddling about, I was able to reclaim a large amount of space with tune2fs:

wim@wim-ubuntu:~/Desktop$ df -h | grep sdc
/dev/sdc1             1.8T  1.7T  352M 100% /media/data
wim@wim-ubuntu:~/Desktop$ sudo tune2fs -l /dev/sdc1 | grep 'Reserved block count'
Reserved block count:     24418900
wim@wim-ubuntu:~/Desktop$ sudo tune2fs -m 0 /dev/sdc1
tune2fs 1.41.14 (22-Dec-2010)
Setting reserved blocks percentage to 0% (0 blocks)
wim@wim-ubuntu:~/Desktop$ sudo tune2fs -l /dev/sdc1 | grep 'Reserved block count'
Reserved block count:     0
wim@wim-ubuntu:~/Desktop$ df -h | grep sdc
/dev/sdc1             1.8T  1.7T   94G  95% /media/data

Apparently linux reserve 5% of new partitions for the root user and system services, so that when you run out of disk space, root can still log in and clean stuff up with system services running ok. Seems kind of bananas to me when the system services only need a hundred meg or so, and 5% of a 2TB drive is a $h17load more than that.. shrugs

This left me with 93.5 GB free, which still leaves about 30 gig unaccounted for, so if anyone has any more ideas feel free to chip in!

Answer 2

Did you rsync your files also using the -H option? There may be hard links on the source drive, which will result in duplicated contents on the destination, unless you specify rsync to (try to) preserve the hard links.

This is especially true for e.g. Windows 7 system partition and Windows/winsxs (Windows side-by-side), which contains a lots of hard links to files in the directory hierarchy.

Answer 3

Use the disk space analyzer that comes with the default Ubuntu install. It will show you exactly where the space is used.

Answer 4

the 30GBs may not exist truely. a GB is technically 1024 bytes. diffent operating systems may count this differently, either by 1024 as is correct, or simply 1000 (called a GiB, but we use them interchagable). this can result in a 1TB showing up in windows as only 931GB (personally experience). people ask where the extra 60gb went, truth is, they didnt go anywhere, they just aren't counted properly. so your 30GB may just be an issue of windows and linux like to count it differently, whether 1000, or 1024. now this doesnt make a large difference when only in Gigabytes, but lets scale it up. those extra 24 bytes do make a diffence. now scaled up, sometimes a TB is counted as 1,000,000,000,000 bytes. as compared to 1,099,511,627,776 bytes. now that difference come out to about 92 GB (technically GiB lol). hope this helped, its a question i see a lot honestly. "where did all my storage go?"