root@snic10e:~# free -m
              total        used        free      shared  buff/cache   available
Mem:        1991508      400700     1571088       16668       19720     1548040
Swap:             0           0           0
root@snic10e:~# echo 3 > /proc/sys/vm/drop_caches
[ 4778.391535] ash (636): drop_caches: 3
root@snic10e:~# free -m
              total        used        free      shared  buff/cache   available
Mem:        1991508      400684     1571104       16668       19720     1548056
Swap:             0           0           0
root@snic10e:~#