how i can increase the size of the root directory .i face some problem of cache of my sql. result of command df -h
# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg_host-lv_root
50G 24G 23G 51% /
tmpfs 16G 0 16G 0% /dev/shm
/dev/sdb1 477M 42M 411M 10% /boot
/dev/mapper/vg_host-lv_home
3.6T 17G 3.4T 1% /home
Now its fine but when load increase space is full and my sql is damaged.