===[root@R430 sites.d]# \free -m ===
total used free shared buff/cache available
Mem: 64181 14933 26029 903 23218 47690
Swap: 0 0 0
===[root@R430 bin]# sync===
===[root@R430 sites.d]# \free -m===
total used free shared buff/cache available
Mem: 64181 14939 26023 903 23218 47684
Swap: 0 0 0
===[root@R430 bin]# sysctl vm.drop_caches=3===
vm.drop_caches = 3
===[root@R430 sites.d]# \free -m===
total used free shared buff/cache available
Mem: 64181 14862 46577 896 2741 47800
Swap: 0 0 0