To easily estimate an impact evaluation associated with a system transition. A function analysis apparatus 1 includes a call input unit 21 that inputs a call to a call processing system 2, an access log acquisition unit 22 that acquires, when the call processing system 2 processes the call, from a function implementation unit 61 included in the call processing system 2, access log data in which an identifier of the function implementation unit 61 that has accessed data to be evaluated and an identifier of a thread when the data to be evaluated is accessed are associated, and an analysis unit 23 that determines a predetermined function implementation unit 61 as a multi-processing unit when identifiers of a plurality of threads are associated with an identifier of the predetermined function implementation unit 61, and determines the predetermined function implementation unit 61 as a single-processing unit when an identifier of a single thread is associated with the identifier of the predetermined function implementation unit 61. 展开▼
