MariaDB MYSQL server down :-(

Thanks a lot Eva for your time!
You really save me

Now don't know how I can clean up this /dev/mapper/vg_server64-lv_root:

Code:

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_server64-lv_root
                       50G   45G  1.7G  97% /
tmpfs                  32G     0   32G   0% /dev/shm
/dev/sda1             477M   87M  365M  20% /boot
/dev/mapper/vg_server64-lv_home
                      745G   86G  622G  13% /home
tmpfs                  32G  3.7M   32G   1% /tmp

 

My XenForo Database is really corrupt because of this problem.
By the way, this problem happens when I transfer a WP site on my server from some client.
Now I think the WP site is infected with malware.
It takes ages on loading on WP admin until my MYSQL server crashed.
And I inspect some of it's file and I found some unknown PHP files that is encrypted.