The memory usage warning in the NFA ->Admin-> System Status page for all Windows 2012 Servers, does NOT match the memory usage seen when looking directly at task Manager on the 2012 server itself.
You may see something like 'memory usage 81 or 82%', but in task manager the usage reported is nothing like this high.
NFA 9.3.3/Windows 2012 only.
Known issue and targeted to be fixed in the next release, which is NFA 9.4, and is due early 2017.
CA Defect - DE55398.
Further Information -
If you see this problem once you are at NFA 9.4, please raise a CA support ticket and reference the CA defect above.