In a disk drive, when an off-track error occurs during a sequential disk access operation that spans multiple contiguous data tracks, efficient recovery is performed. In an embodiment, the disk access operation (e.g., reading from or writing to a disk) is attempted for all sectors of the sequential disk access operation. The disk access operation is then attempted again for sectors associated with any off-track errors that occurred during the disk access operation. In another embodiment, when an off-track error occurs during a sequential write operation in a shingled magnetic recording drive, the data originally targeted to be written to a first portion is written to a second portion of the data track that follows the first portion. Since no additional revolutions of the disk are needed for data associated with the sequential write operation to be written to the disk.

According to one embodiment, a disk device includes a disk, a head that performs data read/write processing on a recording region of the disk, a controller that performs a media scan processing for detecting the presence or absence of a defect in a sector in the recording region of the disk in track unit. When the controller performs the media scan processing on a first sector and a second sector arranged in the track, and a third sector arranged between the first sector and the second sector, the controller performs skip processing in which the controller scans the first sector and the second sector, and does not scan the third sector.

A main controller of an information processing apparatus includes a central processing unit (CPU), and the CPU includes a hard disk drive (HDD) control unit that performs write and read of data on an HDD, and controls the HDD control unit to control write and read on the HDD. In a case where the CPU detects that an error has occurred that write or read of data on the HDD cannot be performed by the HDD control unit, the CPU performs a recovery process that restores an error with respect to an area where the error has occurred.

Systems and methods are disclosed for detection and mitigation of defects within a preamble portion of a signal, such as a data sector preamble recorded to a data storage medium. In certain embodiments, an apparatus may comprise a circuit configured to synchronize a sampling phase for sampling a signal pattern. The circuit may sample a preamble field of the signal pattern to obtain sample values, split the sample values into a plurality of groups, determine defect groups having samples corresponding to defects in the preamble field, remove the defect groups from the plurality of groups, and synchronize the sampling phase based on the plurality of groups.

A method includes moving data in a defect range from a defective area of a data storage medium to a reserve area of the data storage medium, and identifying the defect range by an address of a start of the defect range and a defect length. A logical address table is updated with the address of the start of the defect range, the defect length and an offset to the reserve area.

A control method of an optical disc drive system is provided. Firstly, a first write command is issued to burn a first write data including plural data files to an optical disc in an optical disc drive. If a write fail message from the optical disc drive is received after a specified data block of a specified data file is transmitted to the optical disc drive, the transmission of the first write data is stopped. Then, a data amount of the specified data file that has not been transmitted to the optical disc drive is calculated, and a dummy data with the data amount is generated. Then, the dummy data and the other data files that have not been transmitted are burnt to the optical disc.

According to one embodiment, a magnetic disk device including a disk, a head, and a controller which sets a first track pitch based on fringing when a second track is written, sets a second track pitch based on fringing when a third track is written, calculates a difference between the first track pitch and the second track pitch, sets, when the difference is less than or equal to a reference value, an area to which the first track is written in a first recording area, and sets, when the difference is greater than the reference value, the area to which the first track is written in a second recording area.

A configuration for reducing a possibility of data recording or reproduction being unperformable due to a reading error of disc management information is realized. A data processing unit records management information corresponding to a first surface as main management information on the first surface which is a data recording surface on which data recording is performed and further records mirror management information having the same content as the main management information on a second surface different from the first surface. The management information is, for example, a temporary disc management structure (TDMS) including defect region information of one surface of a disc. When one piece of management information between the main management information and the mirror management information is successfully read, data recording or reproduction can be correctly performed.

Implementations disclosed herein provide for detecting an expected or unexpected power loss event on a storage device. Responsive to the detection of the power loss event, a plurality of potentially affected data blocks are identified and/or marked, such as by a processor, to indicate that data stored therein is potentially corrupted.

A magnetic disk device includes a magnetic disk, which includes, in a track, a plurality of first sectors each recording user data and a second sector recording parity data for restoring the user data recorded in the first sectors, and a disk controller configured to read data from a plurality of sectors including the first sectors and the second sector based on an instruction from a host, and to detect whether there is an error in each of the first sectors when the user data is read from the first sectors. The disk controller continues reading the data recorded in the plurality of sectors even when an error is detected in one of the first sectors by the disk controller.