Linux - Clearing the system cache

Needing to clear the system cache?

carbon:$ free -m
     total     used    free   cached
Mem:  3765     3255     510     1294

you can do

# echo 3 > /proc/sys/vm/drop_caches

or

# sysctl -w vm.drop_caches=3

now

carbon:$ free -m
     total     used    free   cached
Mem:  3765     2071    1694     372