The USE method is a system analysis strategy used to perform a complete check of the health state of the system (which is not necessarily an IT system) and identify bottlenecks or misbehaviours. This method, formalized by Brendan Gregg, is the acronym of Utilization, Saturation and Errors.
The USE method is based on the creation of a checklist of resources to check in a precise and structured manner so that efficiency of diagnostics operations can be maximized.