According to one embodiment, a magnetic disk device includes heads and a controller. The heads write data in a recording region of the magnetic disk. The controller divides in order, by a track group with a constant size, an entire region of the recording region where management regions indicating physical positions corresponding to the heads, respectively, creates the track groups so as to straddle the management regions at boundaries of the management regions, and controls writing of the data for each of the track groups. The controller assigns unique and logically consecutive numbers to the track groups and manages information on the management regions to which the track groups belong.

According to one embodiment, a magnetic disk device, includes a disk including a track including a plurality of servo sectors, a head including a write head which writes data to the disk and a plurality of read heads which read the data from the disk, and a controller configured to simultaneously acquire a plurality of pieces of correction data for repeatable runout of the disk by the read heads, acquire a first correction data and a second correction data based on the correction data, write the first correction data and the second correction data to the disk, and correct a position of the head based on the first correction data and the second correction data.

According to one embodiment, a magnetic disk device, includes a disk including a track including a plurality of servo sectors, a head including a write head which writes data to the disk and a plurality of read heads which read the data from the disk, and a controller configured to simultaneously acquire a plurality of pieces of correction data for repeatable runout of the disk by the read heads, acquire a first correction data and a second correction data based on the correction data, write the first correction data and the second correction data to the disk, and correct a position of the head based on the first correction data and the second correction data.

A tape drive, according to one embodiment, includes: a processor, and logic which is integrated with the processor, executable by the processor, or integrated with and executable by the processor. The logic is configured to: determine whether a difference between information and corresponding design values is in a range. The information corresponds to how an array of writers write and/or are expected to write to a magnetic medium during shingled recording. Moreover, the logic is configured to: compute, using the information, data describing a lateral writing position to use during writing such that shingled track edges are aligned according to a format in response to determining that the difference between the information and corresponding design values is not in the range.

Mounting a data storage medium having information recorded thereon, where: the information is formatted according to a data storage format standard that includes first write and read functions, the information includes first and second datasets, the first dataset includes a first file mark, an index, and an empty space between the second dataset and a combination of the first file mark and the index; receiving, from a first application, a data block and a write command for writing the data block onto the data storage medium; and in response to receiving the write command: determining that the empty space is present in the first dataset, writing, by a second write function, the data block into the empty space, and writing a second file mark in the second dataset; wherein the empty space of the data storage medium is inaccessible to the first write function of the data storage format standard.

When a shingled magnetic recording (SMR) hard disk drive (HDD) receives a write command that references one or more target logical block addresses (LBAs) and determines that one or more target LBAs are included in a range of LBAs for which data are stored in a memory of the drive, additional data are written to the media cache of the SMR HDD along with the write data during the same disk access. The additional data include data that are stored in the volatile memory and are associated with one or more LBAs that are adjacent in LBA space to the target LBAs. The one or more LBAs that are adjacent in LBA space to the target LBAs may include a first group of LBAs that is adjacent to and follows the target LBAs and a second group of LBA that is adjacent to and precedes the target LBAs.

An information recording apparatus includes: a first memory which stores synchronization data for updating data on a recordable optical disc and/or adding data to the recordable optical disc; a second memory which stores erasure information indicating data to be erased; and a controller which controls addition, update, and erasure of data on the optical disc. The controller records the synchronization data onto the optical disc. After recording the synchronization data, the controller records, onto the optical disc, management information indicating the state of the optical disc on which the synchronization data has been recorded and the state of the optical disc resulting from erasure according to the erasure information. Subsequently, the controller closes the session. After closing the session, the controller physically erases the data to be erased which has been recorded on the optical disc.

A method for managing data bands within an interlaced magnetic recording (IMR) architecture includes transmitting read/write characteristics of a logical block address space, the read/write characteristics including coupling information characterizing a physical arrangement of data blocks associated with different logical zones in the logical block address space, where each of the logical zones spans a continuous range of logical block addresses mapped to a series of data blocks physically interlaced with another series of data blocks corresponding to another one of the logical zones. The method further provides for executing a write command instructing a data write to a target logical zone of the logical zones, the write command being generated based on the transmitted coupling information.

According to one embodiment, a magnetic disk device includes a disk, a head, and a controller configured to control the head based on a plurality of upper parameter groups each corresponding to a plurality of upper areas among a plurality of parameter groups each corresponding to a plurality of recording areas into which the disk is divided in a radial direction, the upper areas each corresponding to the recording areas, and a plurality of lower parameter groups each corresponding to a plurality of lower areas into which the upper areas are each divided in the radial direction, the lower parameter groups being different from the upper parameter groups among the parameter groups.

Various implementations of hard disk track management method, device, and system disclosed herein enable improvements of file system write bandwidth. In various implementations, a method is performed at a disk storage including a file controller controlling a disk drive with a disk platter that is divided into multiple regions including a fast region. In various implementations, the method includes receiving a write request associated with data to be written to the disk drive and in response, determining a disk utilization of the disk drive. In various implementations, the method further includes placing the disk drive in a surge mode to write the data to the fast region upon determining that the disk utilization is above a first threshold, and placing the disk drive in a non-surge mode to write the data to other regions of the multiple regions upon determining that the disk utilization is below a second threshold.