nixCraft

raj · #1 (**permalink**) 01-28-2007, 02:50 PM

Ok, don't Laugh at me why is there a mismatch between df and du outputs?

Code:

df /home
du /home

TIA

monk · #2 (**permalink**) 01-28-2007, 02:57 PM

Linux/UNIX inode plays very important roll. A system can not deallocate an inode until Linux or UNIX has closed the file.

Another possibility is unlikned inode which is not allowing to reclaimed free space. Thus it result into different du and df output.

nixcraft · #3 (**permalink**) 01-28-2007, 03:16 PM

See Why command df and du reports different output?

NVRAM · #4 (**permalink**) 05-12-2007, 02:10 AM

Quote:

Originally Posted by nixcraft

See Why command df and du reports different output?

The open-file-descriptor gotcha is one I've seen lots of users trip over with daemons that would grow their log files without bound. This page expains it pretty well, but...

It is a bit misleading since on most systems "vi" does not keep the file opened, if you see the expected differences then I'd be surprised. A better example would be to run:

sleep 120 < /home/user/demo.txt &

instead of vi on another terminal/console. Then remove, check usages, kill the job, then check again.

Cheers.

PS: On many/most Linux systems with a "/proc" filesystem, you can find open, deleted files with:
ls -l /proc/[0-9]*/fd | grep ' (deleted)$'

PPS: Presuming you have permissions, you can often access the file by that symbolic link; use 'wc' to determine the size or even copy the contents back to a disk file.

rockdalinux · #5 (**permalink**) 05-14-2007, 05:51 PM

Quote:

Originally Posted by NVRAM

T
PS: On many/most Linux systems with a "/proc" filesystem, you can find open, deleted files with:
ls -l /proc/[0-9]*/fd | grep ' (deleted)$'

PPS: Presuming you have permissions, you can often access the file by that symbolic link; use 'wc' to determine the size or even copy the contents back to a disk file.

Good explanation, especially wc and deleted files related commands.