[Mageia-dev] df lying?

[Felix Miata]

On 2013-01-07 15:15 (GMT+0200) Anssi Hannula composed:

> Felix Miata composed:

>> What is upstream for df command? In openSUSE 12.2, Cauldron & F18 on the
>> same 64 bit system, df on the only partition on my 1TB data HD is
>> obviously lying as to usage and free on a nearly full EXT2 partition:

>> # df    # before copy Filesystem     1K-blocks      Used Available Use%
>> Mounted on /dev/sdb1      968990412 942397904  26592508  98%
>> /disks/esata

>> -rw-rw-r-- 1 5548561312 Jan  6 14:59 monk0714IonE-201301061400s2.ts
>> -rw-rw-r-- 1 5548200540 Jan  6 15:59 monk0715IonE-201301061500s2.ts
>> -rw-rw-r-- 1 5548657192 Jan  6 16:59 monk0716IonE-201301061600s2.ts
>> -rw-rw-r-- 1 5547676772 Jan  6 17:59 monk0801IonE-201301061700s2.ts
>> -rw-rw-r-- 1 5546660256 Jan  6 18:59 monk0802IonE-201301061800s2.ts
>> -rw-rw-r-- 1 5547738436 Jan  6 19:59 monk0803IonE-201301061900s2.ts
>> -rw-rw-r-- 1 5548427644 Jan  6 20:59 monk0804IonE-201301062000s2.ts

>> # df    # after copying above 37,925,705K bytes in 7 files to #       #
>> /disks/esata from another system on the network Filesystem     1K-blocks
>> Used Available Use% Mounted on /dev/sdb1      968990412 942397904
>> 26592508  98% /disks/esata

>> Unless this is a bug in df, how is this lack of info possible given the
>> following filesystem info (e.g., no reserved blocks, and no journal)
>> about the partition?

>> tune2fs 1.42.5 (29-Jul-2012) Filesystem volume name:   full1TazboxWD
>> Last mounted on:          /disks/esata
> [...]
>> Free blocks:              6648127

> This seems to be in line with the above "df" output.

> What is the result of "du -sk /disks/esata"? It should be approximately
> same as the number of used 1K-blocks in "df" output (968990412).

$ df /disks/esata
Filesystem     1K-blocks      Used Available Use% Mounted on
/dev/sdb1      969063752 942471244  26592508  98% /disks/esata

$ du -sk /disks/esata
942397900       /disks/esata

difference in free count: 73344

Repeating after umounting, fsck.ext2 -f /dev/sdb1 then remounting changed 
nothing.

fsck output included:
528/61054976 files
237541825/244189952 blocks (237541825 * 4 = 950167300; 244189952 * 4 = 976759808)

What could be the reason for the differences, all overhang? 0 overhang? 
Something else?

Do total space in df & du output exclude inode blocks?
-- 
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)

  Team OS/2 ** Reg. Linux User #211409 ** a11y rocks!

Felix Miata  ***  http://fm.no-ip.com/