A computer system of the present invention can adjust the execution frequencies of a command issued from a host and a command issued from a storage. An external manager disposed in the host configures a priority for a host command issued from a command issuing module inside the host. An internal manager disposed in the storage configures a priority for an internal command issued from a command issuing module inside the storage. The internal manager adjusts the execution frequency of the host command and the execution frequency of the internal command based on the host command priority and the internal command priority.