Different size for ls -l and du -ks for a file

[Catherine Forget]

Hi,
I have 3 files with the same size when I do ls -l, but if I do du -ks the answer is very different with one of them. Any idea why?
I copied the file somewhere else and got a different 'du' for the file.

Any idea? the file was recreated and seems to always give the same size...
Thanks

[Patrick Wallek]

These are sparse files.

The size given by 'ls -l' is the size the file was created as in Oracle.

The size given by 'du' is the amount of data actually in the file.

[Steven E. Protter]

Shalom,

Two diffrent tools, two different ways of calculating used space.

SEP

[James R. Ferguson · Accepted solution]

Hi Catherine:

The first difference in size is that 'ls' reports characters and 'du -k' reports 1024-character _blocks_. The smallest block size will be that which the underlying filesystem was created with --- the 'bsize' value reported by 'mkfs -m'.

The tip-off that the files are sparse is their inflation when you use 'cp' to copy them. Database files are commonly allocated as sparse ones.

Regards!

...JRF...

[Dennis Handly]

"ll -e" should provide the extend info for your sparse files.

[Catherine Forget]

Thanks for the info

[Catherine Forget]

thanks