A method for a computer including a processor that is capable of counting invalidation of translation lookaside buffers and generating an interrupt at the occurrence of the invalidation, the invalidation being performed by an operating system upon switching between application programs, includes acquiring identification information of application programs from the operating system and storing the identification information as a first list; detecting an interrupt generated from the processor at the occurrence of switching from a first application program to a second application program; and when the interrupt is detected, acquiring the identification information of the first and second application programs from the operating system or the mechanism and comparing the acquired identification information with the first list to determine whether either of the first and second application programs is a program that has been created or disappeared.