I know the thread is a bit older but I just came across it through Google. I had a similar issue where System was using between 8 GB and 10 GB out of 16 GB total. After uninstalling the Unraid Connect plugin and rebooting, the RAM usage of System dropped to 1.33 GB. What a MASSIVE reduction. I have no clue what Unraid Connect is doing. Possible memory leak issues?!