I forgot to write down here some more information:
$ free -h
total used free shared buffers cached
Mem: 5.8G 4.2G 1.6G 2.9G 64M 3.2G
-/+ buffers/cache: 928M 4.9G
Swap: 511M 0B 511M
/etc/fstab
/dev/sda3 / ext4
rw,relatime,data=ordered 0 1
/dev/cdrom /media/cdrom iso9660
ro,user,noauto,unhide 0 0
/swapfile none swap defaults
0 0
--
Regards from Pal
