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.

According to an embodiment, a track includes first sectors and a second sector. When write of a second data segment to a third sector that is one of the first sectors is requested from a host, a controller acquires the second data segment from the host and stores the second data segment in the memory, and reads a data set including all first data segments and all first information pieces from the track and stores the data set in the memory. The controller acquires a second information piece of the third sector, and updates a first data segment and a first information piece read from the third sector in the data set in the memory with the second data segment and the second information piece. The controller calculates a second parity while the updated data set to the track, and writes the second parity to the second sector.

A magnetic disk device includes a plurality of tracks and a controller. The controller receives write data to be written to a first sector of a track, generates a first data string based on the write data and a logical identifier for the first sector, attempts to cause the first data string to be written to the first sector, determines whether a write error has occurred while the first data string is written to the first sector, generates a second data string based at least in part on the first data string, and in response to determining that no write error has occurred while the first data string is written to the first sector, writes a parity data string that is based at least in part on the second data string to a second sector of the track that stores parity data for the track.

Methods and systems for detecting hidden sectors in a hard drive. The method may include initiating a linear copy of the hard drive and, while the hard drive is being copied, capturing images of a platter and an actuator arm within the hard drive using an imaging device. The captured images are output and they indicate a range of movement of the actuator arm across the platter during the linear copy. Ranges of movement that fail to scan across the full expected size of the platter may be indicative of a modified partition record that maliciously hides a portion of the hard drive from the copy operation.

According to one embodiment, a defect registration method includes measuring, performing first extracting, and registering. The measuring is measuring, on a unit-area basis, performance of a storage area of a magnetic disk including a plurality of unit areas. The storage area includes a redundant area of a set capacity. The first extracting includes second extracting one or more unit areas in order of increasing the performance. The registering is registering the extracted unit areas of the set capacity as defect locations.

The disclosed technology provides a method that improves CCT in SMR device systems. In one implementation, the method comprises writing data to a shingled magnetic recording (SMR) band in a storage device, determining whether an off-track write has occurred, identifying unsafe written data in response to determining that an off-track write has occurred, determining whether caching space is available upon identifying unsafe written data, continue writing data to the SMR band without a write retry upon determining that caching space is available, and writing unsafe written data to the available caching space. In another implementation, the method comprises receiving a request to repair an encroached track in an SMR band, recovering encroached data to a dynamic random-access memory, determining whether caching space is available, writing the recovered data to the available caching space upon determining that caching space is available, and merging other cached data in the SMR band.

An object of the preset invention is to prolong the life of an HDD by performing load/unload control without reducing usability. The present invention is an information processing apparatus including: a hard disk drive; a control unit configured to perform control so that a load state in the hard disk drive is kept for a predetermined time; and a derivation unit configured to derive the number of times of load/unload in the hard disk drive, and the information processing apparatus further includes a change unit configured to change the predetermined time during which the load state is kept based on the operation time of the information processing apparatus and the number of times of load/unload.

Methods, apparatuses and systems for detecting defective sectors on a recording medium. A defective sector detector apparatus comprises an error-corrected ECC symbol number calculator and a defective sector determination unit. The error-corrected ECC symbol number calculator is configured to count a total number of error correcting code (ECC) symbols that are error-corrected in data read from data sectors on a track of a recording medium of the storage device. The defective sector determination unit is configured to receive the total number of ECC symbols that are error-corrected for a data sector from the error-corrected ECC symbol number calculator and determine whether the total number of ECC symbols that are error-corrected exceeds a threshold value. If it is determined that the total number of ECC symbols that are error-corrected exceeds the threshold value, the defective sector determination unit outputs information indicating the data sector to be a defective sector.

According to one embodiment, a magnetic disk device includes a disk that includes a plurality of tracks, each track including a plurality of sectors for storing data, a head that is for writing data to the plurality of sectors and reading data from the plurality of sectors, and a controller. The controller is configured to determine that a first sector of the plurality of sectors is not able to be read and is a defective sector, determine that a second sector of the plurality of sectors is disposed along a line that extends through the first sector and a defective sector included in a first list of defective sectors, register the second sector in the first list of defective sectors, and reallocate an address corresponding to the second sector to a first alternative sector included on 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.