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 track of an optical disk is formed by wobbling and divided into zones, a clock ratio of a recording clock to a wobble clock is preset for each zone, a wobble signal is detected from the optical disk, the wobble clock is generated from the wobble signal, a present position is identified by reproducing ADIP indicating a position of the track from the wobble signal and the wobble clock, the recording clock is generated with respect to the wobble clock, a data address present position is identified from the present position, a start end position of the ADIP in a recording target zone, a start end position of the data address in the recording target zone, and the clock ratio, a recording start position is identified based on the data address present position; and the data is recorded from the recording start position of the recording target zone.

The disclosure is related to systems and methods of On the Fly Formatting. Various parameters that influence areal density of hard disc regions can be changed on the fly based on storage capacity and reliability needs. Further adjustments can be made to the formatting of the region to fine tune achievable storage capacity and reliability values. In some cases, the formatting can include error correction code strength, gap widths between user data sectors and servo data sectors, other characteristics or parameters, or any combinations thereof.

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.

Various zone forwarding management techniques disclosed herein generally provide efficient methods of data caching, steering, mapping, and migration to reduce write amplification and command latency. In one implementation, a zone-forward storage medium management method includes receiving commands to write data sets to target LBAs included in a consecutive sequence of LBAs, selectively mapping the sequence of LBAs to a plurality of contiguous physical zones, and selectively writing the data sets to the physical zones. Various techniques may be used to migrate valid data of the plurality of physical zones to one physical zone.

A write command is received to write data in a target zone including one or more tracks and it is determined whether a data structure is stored in a memory for counting writes performed in a track of the target zone. If such a data structure is not stored in the memory, at least one Low Repeat Write (LRW) data structure is created for the target zone to count writes in sectors of respective tracks of the target zone since creation of the at least one LRW data structure. In another aspect, a write count for a segment is incremented in a data structure for a track to account for a write in the segment. A current overall Track Interference (TI) write count for the target zone is incremented if the incremented segment write count is the highest write count among respective segment write counts in the data structure.

A hard disk drive includes a base deck, a motor coupled to the base deck, a magnetic recording medium coupled to the motor and having a first zone and a second zone, and a controller. The controller is programmed to cause the motor to rotate at either a first speed or a second speed when data is to be read from the first zone and to cause the motor to rotate at the first speed when data is to be written to the first zone and the second zone.

Technologies are provided for partially updating shingled magnetic recording (SMR) zones in SMR storage devices. An SMR storage device can receive and process a command to update a write pointer for an SMR zone to point to an arbitrary write position within the SMR zone. A partial SMR zone update command can be received and processed to modify part of the data stored in the SMR zone. A write position within the SMR zone where data to be modified is stored can be identified. Data stored in the SMR zone following the identified write position can be read to a temporary location and modified. A write pointer for the SMR zone can be updated to point to the identified write position. The modified data can then be written to the SMR zone, starting at the write position identified by the write pointer, or to another SMR zone of the storage device.

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.

Technologies are provided for partially updating shingled magnetic recording (SMR) zones in SMR storage devices. An SMR storage device can receive and process a command to update a write pointer for an SMR zone to point to an arbitrary write position within the SMR zone. A partial SMR zone update command can be received and processed to modify part of the data stored in the SMR zone. A write position within the SMR zone where data to be modified is stored can be identified. Data stored in the SMR zone following the identified write position can be read to a temporary location and modified. A write pointer for the SMR zone can be updated to point to the identified write position. The modified data can then be written to the SMR zone, starting at the write position identified by the write pointer, or to another SMR zone of the storage device.