The present invention aims to specify a bottlenecked resource more accurately in an IT system.
In a performance analysis apparatus which includes a processing device, a storage device and an input/output interface and analyzes a performance of an IT system, the processing device creates an overall performance prediction model by using a nonlinear regression algorithm with a first overall performance value being set as an objective variable and with a first resource performance value being set as an explanatory variable, creates an explanatory model by inputting the overall performance prediction model and using an XAI technology and calculates a degree of per-resource influence on the overall performance value which is output by inputting a second resource performance value into the explanatory model.