If you navigate in your Samsung Galaxy S6 in the menu and then open the app "Smart Manager", then you will notice that your RAM is busy usually between 70% and 90%.
Definitely do you imagine the question: Why is the Ram of my Samsung Galaxy S6 in use, even though I'm no apps at the moment?
The answer is as follows:
Android optimized memory usage of RAM are thus independent. This apps will only be removed from the RAM when the memory is needed by a new app. The advantage is that the faster already open apps can be launched. The charging process an application is shorter. This means that you do not have to try to get free ram, because the Android system memory always as well as possible exploits.
We hope that you understand now why the RAM of your Samsung Galaxy S6 is busy, and why it makes no sense to empty this manually.