Knowing how to determine your server's free disk space and where that space is being used is essential. Thus, I will demonstrate the bash commands du and df, which help with this. Additionally, we will examine the free command for reporting memory usage.

Show Disk Usage

Show the disk usage of your root directory. The following uses df with the -h parameter to show the output in human readable form.

df -h /

# output
Filesystem      Size  Used Avail Use% Mounted on
/dev/nvme0n1p3  118G   16G  100G  14% /

df manpage (opens new window)

Explore Directories

In order to explore the current directory you can use the du command. Again we are using the -h parameter to show the output in human readable form and then we also use the -s parameter to summarize the output. The * is used the show the output of all the folders in the current directory.

du -h -s *

# output
1,1G	Applications
68G	codes
76K	Desktop
26G	Documents
8,0K	Downloads
4,0K	Music
1,2G	Pictures
4,0K	Public
1,9G	snap
4,0K	Templates
18G	Videos

du manpage (opens new window)

Show Memory Usage

Besides disk space it important to know the memory usage. We are going to use the free command to report us on the memory usage.

# memory usage in megabyte
free --mega

# memory usage in gigabyte
free --giga

# output
               total        used        free      shared  buff/cache   available
Mem:           16703        6836         578         391       10033        9866
Swap:           8589           0        8589

free manpage (opens new window)

Source

https://www.howtogeek.com/409611/how-to-view-free-disk-space-and-disk-usage-from-the-linux-terminal/