What is difference between ls -lh and du -sh?

Question

$ ls -lh file1.tar

-rw-r--r-- 1 wnice wnice 40K Aug  6 20:41 file1.tar

$ du -sh file1.tar

80K     file1.tar

Why is it showing different sizes of same file? Please help me understand

Possible duplicate of Why does ls -l output a different size from ls -s? — pLumo, Aug 06 '19 at 15:28
Duplicate is not du vs ls, but ls vs ls -s. The answer is the same. — pLumo, Aug 06 '19 at 15:29
Also: https://unix.stackexchange.com/questions/371238/what-is-the-difference-between-file-size-in-ls-l-and-du-sh — pLumo, Aug 06 '19 at 15:30
See: https://askubuntu.com/questions/122091/difference-between-filesize-and-size-on-disk — Terrance, Aug 06 '19 at 16:23
See: https://serverfault.com/questions/290088/what-is-the-difference-between-du-h-and-ls-lh — VictorLee, Jul 02 '21 at 13:57

Elias · Answer 1 · 2019-08-06T16:47:51.783

7

The du command shows how much disk space is used for the given file.

In contrast, the ls command shows the size of the file. The space used can be larger than the file size, depending on the filesystem used.

For example, we can create a file with the size 1 byte like this (just one newline character in the file):

echo > tmp.txt

Then check its size using ls -l which shows the size one byte:

ls -l tmp.txt 
-rw-r--r-- 1 elias elias 1 aug  6 17:50 tmp.txt

Then check the used space using du:

du -h tmp.txt 
4,0K    tmp.txt

So the used disk space was in this example 4 kilobytes, although the filesize is only one byte.

edited Aug 06 '19 at 16:47

answered Aug 06 '19 at 15:57

Elias

2

du is showing the block size and since the file size is smaller than the 4K block size it will only show you the 4K. If the file was 5K in size it would now show 8K being used. sudo blockdev --getbsz /dev/sda1 should show the block size of the drive being used. – Terrance Aug 06 '19 at 16:25
1

None of that explains why a file that is 40K in size would occupy 80K of disk space. – Tilman Jul 05 '22 at 12:11

1 Answers1