The place on the cloud hosting is occupied by system and other things, is this normal?

Question

linux

The cloud hosting plan comes with 20GB. I had to increase the space to 30GB to work.
Of these, 10 GB was immediately occupied by Linux files and directories.

For example,

du -h --max-depth=1 /                                                                                                
4.0K    /srv                                                                                                                           
600M    /opt                                                                                                                           
1.1M    /tmp                                                                                                                           
16K     /lost+found                                                                                                                    
4.0K    /mnt                                                                                                                           
132K    /root                                                                                                                                                                                                                                                                                                           
4.0K    /media                                                                                                                         
26G     /var                                                                                                                           
61M     /etc                                                                                                                           
0       /dev                                                                                                                           
481M    /boot                                                                                                                          
0       /sys                                                                                                                           
49M     /run                                                                                                                           
4.0K    /home                                                                                                                          
2.9G    /usr                                                                                                                           
30G     /                            

du -h --max-depth=1 /var/
861M    /var/cache                                                                                                                     
4.0K    /var/adm                                                                                                                       
4.0K    /var/crash                                                                                                                     
4.0K    /var/opt                                                                                                                       
16G     /var/www                                                                                                                       
4.0K    /var/preserve                                                                                                                  
436K    /var/tmp                                                                                                                       
11M     /var/spool                                                                                                                     
4.0K    /var/local                                                                                                                     
16K     /var/ftp                                                                                                                       
4.0K    /var/nis                                                                                                                       
4.0K    /var/yp                                                                                                                        
12K     /var/kerberos                                                                                                                  
141M    /var/log                                                                                                                       
4.0K    /var/gopher                                                                                                                    
8.0K    /var/var                                                                                                                       
8.0K    /var/empty                                                                                                                     
9.1G    /var/lib                                                                                                                       
280K    /var/named                                                                                                                     
20K     /var/db                                                                                                                        
4.0K    /var/games                                                                                                                     
26G     /var/

The question is, is this actually normal?

Answer 1

This is the difference between hosting and VPS.
In the case of hosting, the provider is responsible for setting up the system. You are allocated a place for your site and your database. All. But you cannot influence the OS settings in any way, except perhaps within the control panel allocated to you.
In the case of VPS - you get a server. Essno, the OS must take some place. But you are absolutely free in the installed software, its settings. And you pay not for the space occupied by your site, but for the entire server. And setting up the server lies solely on your shoulders.

Answer 2

Usually system files occupy 2-3GB.
If there is only one filesystem, then this command will show the largest directories
du -kx | sort-rn | head -20

Answer 3

For comparison - VPS, on which there are several small sites.

# du -h --max-depth=1 /
232M	/lib
1,4G	/var
736M	/usr
2,4G	/
# du -h --max-depth=1 /var/
705M	/var/www
274M	/var/log
345M	/var/lib
105M	/var/cache
1,4G	/var/
# du -h --max-depth=1 /var/lib/
219M	/var/lib/mysql
3,1M	/var/lib/nginx
101M	/var/lib/apt
345M	/var/lib/

Answer 4

Fine. Depends on the type of virtualization.