"Missing" disk space

linuxqueric · 12-30-2009, 02:32 PM

I've got a 500GB external HDD that's divided into four partitions. My problem is understanding the space usage in the partition that I use for my rdiff-backup (#4 in the table below).

For reference:

Code:

      Capacity   Used   Contents   Free Space  fs
1     39.1       17.8   17.4       21.2        msdos

2     104.9      53.8   53.7       43.8        ntfs-3g

3     234.4      163.2  121.7*     71.2        mac os x

4     93.2       84.2   18.8*      9.0         ext3

*"(some contents unreadable)"

So the question is, what's going on with this 4th partition--84 GB "used" but only 19 GB "content"? (By the way, when it mounts the openSUSE system chooses to call it "101.6 GB Media"--why is "capacity" only 93.2?)

After fsck on the partition, I get the following from ls -al:

Code:

linux-oe0e:~ # fsck -t ext3 /dev/sdb4
fsck 1.41.1 (01-Sep-2008)
e2fsck 1.41.1 (01-Sep-2008)
Adding dirhash hint to filesystem.

/dev/sdb4 has been mounted 87 times without being checked, check forced.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information

/dev/sdb4: ***** FILE SYSTEM WAS MODIFIED *****
/dev/sdb4: 293325/12419072 files (1.5% non-contiguous), 21211299/24816408 blocks


linux-oe0e:/media/disk-1 # ls -al
total 64
drwxr-xr-x 9 eric root       4096 Dec  3 12:31 .
drwxr-xr-x 3 root root       4096 Dec 30 13:51 ..
drwx------ 4 eric users      4096 Jan 17  2009 .Trash-1000
drwx------ 2 eric vboxusers  4096 Sep  8  2008 .Trash-eric
-rwxrwxrwx 1 eric vboxusers  1790 Dec  3 12:31 Backup_to_Iomega
-rw-rw-rw- 1 eric vboxusers  1765 Oct 21 08:16 Backup_to_Iomega~
drwxr-xr-x 6 root root      12288 Dec 16 07:16 Home-backup
drwxr-xr-x 4 eric users      4096 Feb 14  2009 OldRdiff_Ubuntu
drwx------ 2 root root      16384 Mar 23  2008 lost+found
drwxr-xr-x 8 eric users      4096 Nov 21 14:48 mnemosyne
drwxr-xr-x 3 eric users      4096 Nov 21 14:49 readerware

This doesn't seem to me to give any clue as to where the missing space is used.

Some other threads related to this suggested checking with tune2fs -l and dumpe2fs. The latter report comes back at 4621 lines, the first 43 of which are the same as the output from tune2fs -l. Reserved block count is 1240820. But the interesting thing is the other 4568 lines.

My guess, from what I read, was that this represents the size of the superblock. But "dump2fs |grep -i superblock" only returns about 14 lines. This is a sample of what seems to go on throughout the output:

Code:

Group 90: (Blocks 2949120-2981887)
  Block bitmap at 2949120 (+0), Inode bitmap at 2949121 (+1)
  Inode table at 2949122-2949633 (+2)
  0 free blocks, 16348 free inodes, 0 directories
  Free blocks: 
  Free inodes: 1474597-1490944
Group 91: (Blocks 2981888-3014655)
  Block bitmap at 2981888 (+0), Inode bitmap at 2981889 (+1)
  Inode table at 2981890-2982401 (+2)
  3159 free blocks, 16377 free inodes, 0 directories
  Free blocks: 3011154-3014312
  Free inodes: 1490952-1507328
Group 92: (Blocks 3014656-3047423)
  Block bitmap at 3014656 (+0), Inode bitmap at 3014657 (+1)
  Inode table at 3014658-3015169 (+2)
  32232 free blocks, 16381 free inodes, 0 directories
  Free blocks: 3015176-3024895, 3024904-3039231, 3039240-3047423
  Free inodes: 1507332-1523712
Group 93: (Blocks 3047424-3080191)
  Block bitmap at 3047424 (+0), Inode bitmap at 3047425 (+1)
  Inode table at 3047426-3047937 (+2)
  20785 free blocks, 16366 free inodes, 0 directories
  Free blocks: 3047938-3049471, 3049478-3051519, 3051521-3059711, 3059720-3067504, 3067577-3068107, 3068109-3068165, 3068169-3068287, 3068336-3068861
  Free inodes: 1523731-1540096
Group 94: (Blocks 3080192-3112959)
  Block bitmap at 3080192 (+0), Inode bitmap at 3080193 (+1)
  Inode table at 3080194-3080705 (+2)
  0 free blocks, 16373 free inodes, 0 directories
  Free blocks: 
  Free inodes: 1540108-1556480
Group 95: (Blocks 3112960-3145727)
  Block bitmap at 3112960 (+0), Inode bitmap at 3112961 (+1)
  Inode table at 3112962-3113473 (+2)
  0 free blocks, 16381 free inodes, 0 directories
  Free blocks: 
  Free inodes: 1556484-1572864

So I guess I have these two questions:
1. What's happening with this large block of data?

2. How can I reduce it so I can use the partition for what I need it for?

Thanks.

LQE

AlucardZero · 12-31-2009, 07:18 AM

Post fdisk -l and df -h

linuxqueric · 12-31-2009, 09:00 AM

(The number on sdb4, the partition I'm concerned about, are now a little different, since I ran another rdiff-backup yesterday after posting.)

Quote:

linux-oe0e:~ # fdisk -l

Disk /dev/sda: 80.0 GB, 80026361856 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xed1f86f7

Device Boot Start End Blocks Id System
/dev/sda4 * 318 9729 75601890 5 Extended
/dev/sda5 9394 9729 2698920 82 Linux swap / Solaris
/dev/sda6 318 1561 9992367 83 Linux
/dev/sda7 1562 9393 62910508+ 83 Linux

Partition table entries are not in disk order

Disk /dev/sdb: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x679369bf

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 5099 40957686 b W95 FAT32
/dev/sdb2 5100 17847 102398310 7 HPFS/NTFS
/dev/sdb3 17848 48443 245762370 af Unknown
/dev/sdb4 48444 60801 99265635 83 Linux
linux-oe0e:~ # df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda6 9.4G 5.4G 3.6G 60% /
udev 999M 9.3M 990M 1% /dev
/dev/sda7 60G 44G 15G 75% /home
/dev/sdb1 40G 18G 22G 46% /media/IOMEGA_HDD
/dev/sdb3 235G 164G 72G 70% /media/disk1s3
/dev/sdb4 94G 81G 7.7G 92% /media/disk
/dev/sdb2 98G 54G 44G 56% /media/disk-1

AlucardZero · 12-31-2009, 09:16 AM

Ok, and what gave you the very first output you put in code tags in your first post?

linuxqueric · 12-31-2009, 09:38 AM

I created that from the properties window (rt click on the desktop partition icon) for each partition.