Recording medium recording packet analysis program, packet analysis method, and information processing device

A recording medium recording a program for causing a computer to execute processing includes: accumulating a packet in a first memory; accumulating, in a second memory, first information regarding communication performance of a connection which is used to transfer the packet in association with second information indicating the connection based on the packet; registering, for each of connections, the second information in a third memory at time intervals with reference to the second memory in association with one of index value ranges including an index value indicating the communication performance of the respective connections; extracting, with reference to the third memory, a packet which is transferred through a connection corresponding to a specific index value range out of packets that are accumulated in the first memory and for which a first time is elapsed from acquisition of the packets; and storing the extracted packet in a fourth memory.