Abstract: A Data Storage Device (DSD) includes at least one Non-Volatile Memory (NVM) configured to store data and a Non-Volatile Cache (NVC). Write data is stored in a volatile memory in preparation for writing the write data in the at least one NVM. In response to a power loss of the DSD, at least a portion of the data stored in the volatile memory is transferred from the volatile memory to the NVC and one or more parameters are determined for deriving a margin representing an additional amount of data for transfer from the volatile memory to the NVC using a remaining power following a power loss. A size of the NVC is adjusted based at least in part on the derived margin.

Abstract: A data storage device is disclosed comprising a head actuated over a magnetic media comprising a plurality of data tracks, wherein each data track comprises a plurality of data sectors. A plurality of access commands are stored in a command queue, and an access command is selected from the command queue. When the selected access command is a write command to a target data track and at least part of a first data track proximate the target data track needs to be refreshed, a refresh read command is executed to read data from at least part of the first data track prior to executing the write command to the target data track.

Abstract: A write command is received to write data in a Conventional Magnetic Recording (CMR) realm of a disk to be formatted for writing data in non-overlapping tracks. The disk includes a plurality of areas of the disk that can be formatted as a CMR realm or as a Shingled Magnetic Recording (SMR) realm formatted for writing data in overlapping tracks. It is determined whether performance of the write command would require writing to begin in a portion of the CMR realm that has not been written with non-overlapping tracks. In response to determining that the performance of the write command would require writing to begin in a portion of the CMR realm that has not been written with non-overlapping tracks, a predefined data pattern is written using non-overlapping tracks in the portion of the CMR realm that has not been written with non-overlapping tracks.

Abstract: A write command is received to write data in a Conventional Magnetic Recording (CMR) realm of a disk to be formatted for writing data in non-overlapping tracks. The disk includes a plurality of areas of the disk that can be formatted as a CMR realm or as a Shingled Magnetic Recording (SMR) realm formatted for writing data in overlapping tracks. It is determined whether performance of the write command would require writing to begin in a portion of the CMR realm that has not been written with non-overlapping tracks. In response to determining that the performance of the write command would require writing to begin in a portion of the CMR realm that has not been written with non-overlapping tracks, a predefined data pattern is written using non-overlapping tracks in the portion of the CMR realm that has not been written with non-overlapping tracks.

Abstract: In general, techniques are described for writing data to a storage device that comprises an interface and a controller. The interface may receive a request to sequentially write data stored in a first group of tracks to an I-region, where the first group of tracks was also previously written. The controller may move data stored in a second group of consecutive tracks different than the first group of tracks from the I-region to an E-region, the second group having cardinality equal to the tracks that must be moved for the first group to be written sequentially in the I-region. The E-region comprises a portion of the storage device reserved for temporary storage. The controller may determine a position of the I-region where data from one of the second group was previously stored, and write data from the first group of tracks sequentially to the I-region, starting at the position.