Testing functional requirements of your system in the way how it behaves under different types of load is a basic explanation for performance testing. However we test the functions of the system, performance testing is classified under " non-functional testing " because we don't aim to test the functions we want to test how the system is functioning under different amount of loads. Therefore performance testing should be performed after the functional testing has been completed . Performance testing is crucial if you are testing an application which has an un-predictable load of user or if you have specified the quality of service in your Service-Level Agreement (SLA). Performance can not be defined by one of testing criteria since there are number of parameters in the system. I mean by this, there are subsets for performance testing which can be listed as Performance Testing Load Testing Endurance Testing Stress Testing Spike We can explain the differences bet
Not a feature, but the future of an app is under testing.