According to one embodiment, a magnetic disk device includes a disk, a head that writes data to the disk and reads data from the disk, and a controller that executes error correction on a first sector which is unreadable in a first track from an initial reading time of initially one-round reading the first track of the disk based on first parity data corresponding to the first track.

Example read channel circuits, data storage devices, and methods to provide overlapping processing of data tracks are described. The data storage device may include media configured with a plurality of tracks in a concentric or continuous pattern. The read signal for a data track may be processed using error correction codes (ECC) as it is read during a first track read operation period. Some portion of its data sectors may need additional ECC postprocessing after the first track is initially received and processed by the read channel circuit. While the read signal for a next data track is being read and processed, the read channel circuit may continue postprocessing of the portion of data sectors from the first track during the second track read operations. Various decision parameters for managing the data stream, additional postprocessing time, and rereading tracks for data recovery are also described.

In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.

Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator arm assembly comprising one or more heads, and configured to position the one or more heads proximate to disk surfaces of the one or more disks; and one or more processing devices. The one or more processing devices are configured to detect one or more physical defects on a recording medium; designate, in a mapping of the recording medium, the one or more physical defects for exclusion from being assigned to data containers, the data containers configured for assignment of a plurality of logic blocks to the data containers, the logic blocks configured to store the data to be written that are being interleaved across a plurality of sectors based on a distributed sector encoding scheme; and designate one or more artificial defects adjacent to the one or more physical defects for exclusion from being assigned to the data containers in the mapping.

In an approach to using a cut and paste segment for reading an sHKDS, a request to reposition a tape media in a tape drive is received. Responsive to encountering an error reading an sHKDS while attempting to reposition the tape media, one segment of a plurality of segments from a data set cut and paste error recovery procedure (ERP) is used for an sHKDS cut and paste ERP. Responsive to recovering the sHKDS using the sHKDS cut and paste ERP, the one segment reserved for the sHKDS cut and paste ERP is released to the data set cut and paste ERP.

A method and device for testing a memory array structure, and a non-transitory storage medium are provided. The method includes that: respective storage data corresponding to each preset test pattern is written into a to-be-tested memory array, the each preset test pattern being one of preset test patterns in a preset test pattern library; a row aggressing test is repeatedly performed on the to-be-tested memory array until a bit error occurs in the storage data, to obtain row aggressing test times, corresponding to the each preset test pattern, of the to-be-tested memory array, where the bit error characterizes that the storage data has changed; a target preset test pattern corresponding to the to-be-tested memory array is determined from the preset test pattern library based on the row aggressing test times; and an array structure of the to-be-tested memory array is determined based on the target preset test pattern.

A method of recovering data from one or more failed data sectors includes estimating a reader offset position from a first or a second read attempt of the one or more failed data sectors at a current set of channel parameters and basing the estimated reader offset position on, at least in part, a position error signal generated during the first or second read attempt. At least one read is performed on the one or more failed data sectors at the estimated reader offset position to obtain one or more samples. The one or more samples are processed to obtain a processed sample. Iterative outer code recovery is performed on the processed sample.

A method and device for testing a memory array structure, and a non-transitory storage medium are provided. The method includes that: respective storage data corresponding to each preset test pattern is written into a to-be-tested memory array, the each preset test pattern being one of preset test patterns in a preset test pattern library; a row aggressing test is repeatedly performed on the to-be-tested memory array until a bit error occurs in the storage data, to obtain row aggressing test times, corresponding to the each preset test pattern, of the to-be-tested memory array, where the bit error characterizes that the storage data has changed; a target preset test pattern corresponding to the to-be-tested memory array is determined from the preset test pattern library based on the row aggressing test times; and an array structure of the to-be-tested memory array is determined based on the target preset test pattern.

A storage device includes a controller that determines a degree of data degradation for a data track targeted by a pending read command and sets a head/media clearance parameter for execution of the read command based on the determined degree of data degradation for the data track, the head/media clearance parameter providing for a greater head-media separation when the determined level of degradation is lower than when the determined level of degradation is higher.

In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.