To manage Buffer Cache I have searched and collected following information for future use.
Clear the Buffer Cache
To clear the Buffer Cache execute following command in you Linux terminal
echo 3 > /proc/sys/vm/drop_caches
Restrict the Size of the Buffer Cache
To restrict the size of the Buffer Cache execute the following command:
echo 150 > /proc/sys/vm/vfs_cache_pressure
Above information are collected from here.