Why is my S7 Edge using 87% of the RAM all the time? It's not the apps because I use Greenify for stopping background tasks. I see under Developer mode → Running services that my system takes 2 GB of RAM, but why? That's not normal, the S7 Edge has 4 GB of RAM and I can use only 600 megabytes.
I'd say that is absolutely normal. Because: What benefit would you have if your RAM is empty? You have RAM to be used for caching and hibernating apps. Unused RAM is useless. :-)
Do you experience performance issues? Any lag? No? Then the S7's memory management works as it should. :-)