1. A non-transitory computer readable storage medium storing a system analysis program for analyzing operational status of the system including plural servers performing processing operations in cooperation in accordance with a request from a user terminal, the program causing a computer to execute a procedure, the procedure comprising: storing a received time of a downlink packet from an upper-level server to a lower-level server for issuing a processing request to the upper-level server in association with the downlink packet into a packet storage portion and a received time of the uplink packet from the lower-level server to the upper-level server in association with the uplink packet into the packet storage portion; identifying plural combinations of the downlink packet and the uplink packet immediately following the downlink packet under predetermined condition, the uplink packet having a predetermined threshold value or more difference time from the received time of the downlink packet to the received time of the uplink packet; storing the received time of the uplink packet included in the identified combination and the received time of the downlink packet included in the identified combination following immediately after the identified combination in association with chunk identification data into a chunk data storing portion, the chunks of chunk identification data identifying a chunk data from the uplink packet included in the identified combination to the downlink packet included in the identified combination following immediately after the identified combination; identifying from the chunk data storing portion the chunk identification data associated with both of the received time of the uplink packet and the received time of the downlink packet, which are included between the time when the packet of a specific processing request to the lower-level server is received and the time when the packet of the response corresponding to the specific processing request is received; storing the identified chunk identification data into an inclusion relation data storing portion in association with a processing identification data for identifying a specific processing operation to be performed in response to the specific processing request; calculating chunk processing time by using a difference between the received time of the uplink packet and the received time of the downlink packet, which are stored in the chunk data storing portion, on the basis of the chunk identification data associated with the processing identification data; calculating the total sum of the chunk processing times to calculate processing time of the upper-level server for the specific processing operation; and storing the total sum of the chunk processing times into an analysis result storing portion in association with the processing identification data of the specific processing operation.