Abstract: Embodiments of the invention prevent or alleviate head damage ascribable to the TA-causing sections (projections) of disks (TA is thermal asperity). With respect to a TA-causing section that has been detected during initial defect registration, X±A tracks in a radial direction and Y±B sectors (or Y±B bytes of space) in a circumferential direction, with the TA-causing section as a center, are registered collectively during primary registration. Following this, secondary registration is conducted to register a region ranging from±several tens of tracks to several hundreds of tracks present in a radial direction, and all sectors (or all bytes of space) present in a circumferential direction, with a track of the detected TA-causing section as a center. Furthermore, a cylinder of a region equivalent to the same radial positions as those of the secondary registration is registered (as tertiary registration) for all disks, except for the disk where the TA-causing section was detected.

Abstract: Embodiments of the invention prevent or alleviate head damage ascribable to the TA-causing sections (projections) of disks (TA is thermal asperity). With respect to a TA-causing section that has been detected during initial defect registration, X±A tracks in a radial direction and Y±B sectors (or Y±B bytes of space) in a circumferential direction, with the TA-causing section as a center, are registered collectively during primary registration. Following this, secondary registration is conducted to register a region ranging from±several tens of tracks to several hundreds of tracks present in a radial direction, and all sectors (or all bytes of space) present in a circumferential direction, with a track of the detected TA-causing section as a center. Furthermore, a cylinder of a region equivalent to the same radial positions as those of the secondary registration is registered (as tertiary registration) for all disks, except for the disk where the TA-causing section was detected.