If you are running a webserver, Database, or plex server you might find that your memory is at 90%+ all the time. Here is how to clear it up.
1. create a file at /usr/local/bin. I am calling it free-memory but you can call the file what ever you want.
sudo nano /usr/local/bin/free-memory
3. add the command then save and close.
free -h && sudo sysctl -w vm.drop_caches=3 && sudo sync && echo 3 | sudo tee /proc/sys/vm/drop_caches && free -h
2. change the permissions of the script.
sudo chmod 555 free-memory
4. Creating a cron job.
sudo contrab -e
5. I want to run mine every minute. Change this to your needs.
* * * * * /usr/local/bin/free-memory
6. check your server after a minute. you should see your memory usage change.