Patent ID: 7738205

Claim:
A method of managing defective regions in a recording disk drive that includes a head having a read element and a write element different in position from each other in the radial direction of a recording disk, wherein the recording disk drive positions the head while reading out recorded servo data in a servo region from the recording disk by using the read element, the method comprising: executing data write processing with the read element positioned at a target position for performing either normal data read access or normal data write access; determining that a predefined error occurs during the data write processing because of an error-causing servo data, and then estimating an estimated address of user data in a data region for which other normal data read or normal write access is performed using the error-causing servo data as a target; identifying an address of the servo data used as the target for the other access to the estimated address of the user data; comparing the identified address of the servo data and the address of the error-causing servo data to generate a comparison result indicating a match between the identified address of the servo data and the address of the error-causing servo data; and registering a region identified by the estimated address of the user data as a defective region in accordance with the above comparison result that indicates a match, wherein each of a plurality of data regions is sandwiched between the servo regions extending radially from the center of the recording disk and partitioned at required angle intervals.