We have an production environment running SharePoint 2013. Total RAM on each server is 16GB and RAM utilization hits (and goes over 90%) on the web front ends quite often. Our SharePoint engineer responsible for the farm says that 90% RAM utilization is fine for a server running SharePoint. This doesn't seem right. Anyone have any feedback regarding running servers with RAM utilization so high? Does anyone run their farms with such a high threshold? Or would recommend it?