Technology is disclosed for deferring storage operations (e.g., writes or reads) during hostile events. When a data storage device experiences a hostile event, e.g., a vibration, shock, etc. contact by a head of the data storage device with a disk surface can cause errors or indeed damage. The technology can cause a data storage device to suspend storage operations until the hostile event is no longer detected.

A storage device controller is configured to select one of multiple written track widths for a storage location based on a write attribute of data to be recorded at the storage location. According to one implementation, the storage device controller is further configured to select a power level for a heat-assisted magnetic recording (HAMR) device based on the write attribute.

A system includes a read/write module and a caching module. The read/write module is configured to access a first portion of a recording surface of a rotating storage device. Data is stored on the first portion of the recording surface of the rotating storage device at a first density. The caching module is configured to cache data on a second portion of the recording surface of the rotating storage device at a second density. The second portion of the recording surface of the rotating storage device is separate from the first portion of the recording surface of the rotating storage device. The second density is less than the first density.

A method for writing data onto a medium on which data are stored in tracks includes encoding the data into at least one codeword, and writing a respective portion of each of the at least one codeword onto respective different tracks on the medium. The writing may include writing a respective portion of each of the at least one codeword onto respective different adjacent tracks on the medium. Another method for reading data includes positioning a plurality of read heads to read codewords that have been written across multiple tracks of a medium. Each read head in the plurality of read heads reads a different portion of the first group of the multiple tracks, and where each different portion of the multiple tracks overlaps at least one other different portion of the multiple tracks. Signals are detected from the plurality of read heads, and the detected signals are decoded.

An implementation of a system disclosed herein provides a method for managing data streams of sequential nature, wherein the method writes the sequential chunks (fragments) directly to an open band in the order these are received from the host and includes determining an end of the incoming data write request related to streaming data and in response to the determination of the end of the incoming data write request related to streaming data, copying remaining data from a current physical band mapped to logical block addresses LBAs related to the data write requests to the allocated (open) band.

Systems and techniques for writing data to a Shingled Magnetic Recording (SMR) magnetic data storage device. At least one processor may determine whether the distance between a first data track and a second data track is less than a threshold distance. If the distance is less than a threshold distance, the at least one processor may cause a write head to refrain from writing to the sector of the second data track. The at least one processor may cause data from the first data track to be copied to another storage location and write data to the sector of the second data track.

A magnetic disk apparatus of one of the embodiments stores read position dependency information on read signal quality of a data region at a first track and measures the read signal quality at a predetermined radial position in a second data region of a second track different from the first track. A positioning error of the second data region is determined based on the read position dependency information and the read signal quality at the predetermined radial position. Data is recorded in a recording target data region in a shingled recording so as to prevent data written in the second data region from being overwritten by data in a recording target data region adjacent to the second data region by using the determined positioning error.

System, methods, and apparatuses for storing data in a disk-based storage device incorporating multiple readers per recording surface to reduce recovery time from read errors using super-parity. An exemplary storage device comprises a read/write head and an associated recording surface. The read/write head has a plurality of readers configured to read a plurality of data tracks on the associated recording surface concurrently. The recording surface is segmented into a plurality of super blocks comprising a portion of each of a number of adjacent data tracks, the number of adjacent data tracks in each of the plurality of super blocks being equal to the number of the plurality of data tracks that can be read concurrently by the plurality of readers. Each super block further comprises parity information on one of the number of adjacent data tracks containing data recovery information for the super block.

An aspect includes receiving a write request at a storage device. The write request includes data and is received from a file system executing on a host computer communicatively coupled to the storage device. A storage location on the storage device for the data is selected by the storage device based at least in part on characteristics of the storage device. The data is stored at the storage location on the storage device. A write completion message is sent to the file system confirming that the write of the data has been completed. The write completion message includes an identifier of the storage location.

According to one embodiment, a magnetic disk device includes a disk, a head including a main magnetic pole having a first end and a second end opposite to the first end in a radial direction of the disk, a write shield facing the main magnetic pole with a gap, and an assist element provided in the gap and at a position where a first distance between the first end and the assist element and a second distance between the second end and the assist element are different from each other, and a controller which controls a voltage applied to the assist element according to a shingled write direction in which a second track is overwritten on a first track.