Abstract: A data storage device (DSD) including a first non-volatile memory (NVM) media type for storing data and a second NVM media type for storing data. Metadata is obtained related to operation of the second NVM media type. The metadata is evaluated and data stored in the first NVM media type is managed based on the evaluated metadata.

Abstract: A disk drive is disclosed comprising a head actuated over a disk comprising a plurality of tracks, wherein each track comprises a plurality of data sectors comprising a disk block size. A host write command is received comprising data blocks having a host block size less than the disk block size. A misalignment is detected between the data blocks and the disk block size, and when the misalignment is detected, at least one of the data blocks is stored in a write cache. A command rate limit is adjusted as a function of the write cache, wherein the command rate limit defines a limit on a number of commands received from a host.

Abstract: A data storage device is disclosed comprising a non-volatile memory. A command rate profile is initialized, wherein the command rate profile defines a limit on a number of access commands received from a host as a function of an internal parameter of the data storage device. The command rate profile is adjusted in response to a change in operating mode.

Abstract: A data storage device including non-volatile storage is initialized from initialization information stored in an information initialization area. A pointer area is also provided on the non-volatile storage for storing initialization pointer information. Pointer information includes a sequence identifier. A processor is configured to read the storage locations in the pointer area and used the information to locate and read initialization information from the located initialization information area to initialize the data storage device. In one embodiment, sequence identifiers are examined to locate most recent sequence identifier for initialization. In other embodiments, more than one initialization area and/or pointer area may be used for robustness.

Abstract: Write pointer management for a disk drive including a disk having a plurality of sectors and a non-volatile memory (NVM) for storing data. Data is sequentially written sector by sector on the disk. The data written in a sector includes a write status indicator indicating that data has been written in the sector. A write pointer is stored on the disk or the NVM as a check-pointed write pointer. The write pointer corresponds to a current sector for writing data on the disk. During a write pointer recovery process, the check-pointed write pointer is retrieved, and at least one write status indicator is scanned in a range of sectors from the sector corresponding to the retrieved check-pointed write pointer and a last sector to identify the current sector for writing data. The write pointer is set to correspond to the identified current sector.

Abstract: The present invention relates to optimizing the performance of a data storage device, such as a hard data storage device, during boot operations and normal operations. In particular, during power up, the data storage device monitors the nature and progress of commands issued from a host. During boot operations, the data storage device sets its cache to a boot mode. The boot mode is designed to speed the boot process and aggressively cache data used during boot up of the data storage device and the host. The data storage device detects the transition of the host operations from boot operations to normal operations based on various criteria. The caching mode of the data storage device is then changed for normal operations based on the transition.

Abstract: A hybrid drive is disclosed comprising a head actuated over a disk, and a non-volatile semiconductor memory (NVSM). Access commands are received from a host including disk read commands. When a high workload of disk access commands is detected, data of at least one disk read command is migrated to the NVSM.

Abstract: A data storage device (DSD) includes a non-volatile memory (NVM) media for storing data. A last resort zone of the NVM media is associated with a higher risk of data loss or data corruption than other portions of the NVM media and is reserved as unavailable for storing data. It is determined whether a current data storage capacity and/or an environmental condition for the NVM media has reached a threshold. The last resort zone is set as available for storing data if it is determined that the threshold has been reached and data is written in the last resort zone.

Abstract: The present invention is directed to systems and methods for opportunistically defragmenting a data storage device during garbage collection. During garbage collection, valid data is identified and cached in a buffer assigned to the garbage collection process. When the buffer has been filled or reached a threshold, the valid data in the buffer is then coalesced and rewritten back to the data storage medium. In addition, a translation table is reduced by updating its entries to indicate the new locations of the coalesced valid data.

Abstract: A data storage device (DSD) includes a non-volatile memory (NVM) media for storing data. A last resort zone of the NVM media is associated with a higher risk of data loss or data corruption than other portions of the NVM media and is reserved as unavailable for storing data. It is determined whether a current data storage capacity and/or an environmental condition for the NVM media has reached a threshold. The last resort zone is set as available for storing data if it is determined that the threshold has been reached and data is written in the last resort zone.

Abstract: Managing data stored in a Data Storage Device (DSD) including at least one disk for storing data. Data is written in a first region of the at least one disk with a first track density. A frequency of access is determined for the data written in the first region, and the frequency of access is compared to a threshold. Based on the comparison, a copy of the data written in the first region is written in a second region of the at least one disk with a second track density different than the first track density.

Abstract: A data storage device is disclosed comprising a non-volatile memory comprising a plurality of sectors. At least one alignment zone is defined in the non-volatile memory comprising a plurality of chunks including a plurality of data chunks and a plurality of pad chunks, wherein each chunk comprises a plurality of sectors. Each sector is operable to store X host blocks, the alignment zone comprises at least X?1 pad chunks, and control circuitry is operable to shift the data chunks of the alignment zone by a number of chunks equal to or less than X?1 plus a corresponding offset.

Abstract: A non-volatile storage subsystem is described which identifies performance-sensitive commands and heterogeneous performance characteristics of portions of a non-volatile storage media, and matches the performance sensitivity of the commands with an available physical write address corresponding to performance characteristics appropriate for the performance sensitivity of the command. A command can be considered performance sensitive if it originates from a host or a preferred host among a plurality of hosts, or if the command designates a frequently accessed logical address. Performance characteristics of the storage device can be determined by physical architectures of the storage media such as the distance from the axial center of a disk media, or the architecture technology of a solid-state array. Performance characteristics can also be determined dynamically and heterogeneous performance can be encouraged by internal maintenance policies of the subsystem.

Abstract: A data storage device is disclosed comprising a non-volatile memory comprising a plurality of sectors. A partition map is evaluated that identifies a partition accessed through a plurality of logical block addresses (LBAs), where each LBA maps to a fraction of a sector. A partition offset is determined for the partition relative to a boundary of one of the sectors. N write commands are received each having a write offset relative to a corresponding sector. When the write offset for X of the N write commands matches the partition offset, at least part of the partition is moved to align at least part of the partition to a boundary of one of the sectors.

Abstract: Embodiments described herein include systems and methods for maintaining and/or recovering a logical-to-physical address mapping of a storage subsystem. Certain of these embodiments improve system performance by reducing resource and time consumption involved in reconstructing a logical-to-physical mapping at power-up.

Abstract: A hybrid drive is disclosed comprising a head actuated over a disk, and a non-volatile semiconductor memory (NVSM). A first execution time needed to execute commands in a NVSM command queue is estimated, and a second execution time needed to execute commands in a disk command queue is estimated. An access command is inserted into a selected one of the NVSM command queue and the disk command queue in response to the first and second execution times, and one of the first and second execution times is updated in response to an estimated execution time of the access command.

Abstract: The present invention is directed to systems and methods for optimizing garbage collection in data storage. The data storage may be a shingled disk drive or a non-volatile solid-state memory device. Garbage collection is optimized by selectively saving data read from certain locations of the data storage in response to host read commands and using the saved data for subsequent garbage collection operations. The decision of whether to save data may be based on a number of criteria, including whether the data is located in an area of the data storage that is due to be garbage collected in the near future. In this manner, certain garbage collection operations can be performed without having to re-read the saved data.

Abstract: A disk drive is disclosed comprising a head actuated over a disk including a plurality of contiguous servo tracks for defining a plurality of data tracks. A first write command comprising first write data is received, and a first density of first data tracks over a first plurality of the contiguous servo tracks is selected, wherein the first write data is written to the first data tracks. A second write command comprising second write data is received, and a second density of second data tracks over the first plurality of the contiguous servo tracks is selected, wherein the second density is different than the first density. The second write data is written to the second data tracks.

Abstract: A method of refreshing data on a hard disk drive configured to carry out commands issued by a host that comprises tracking run-time conditions related to patterns of host command activity on the hard disk drive; selecting an entry from a high priority pool that is configured to hold a predetermined maximum number of entries, each entry comprising a plurality of tracks having been designated as being eligible for a high priority refresh operation as a result of the host command activity; refreshing data stored on at least one track of the selected entry; pausing the refreshing for a period of time equal to a throttle interval to process at least one command issued by the host before returning to the selecting or to the refreshing, and periodically modifying a value of the throttle interval depending upon the tracked run-time conditions.

Abstract: The present invention is directed to systems and methods for optimizing garbage collection in data storage. The data storage may be a shingled disk drive or a non-volatile solid-state memory device. Garbage collection is optimized by selectively saving data read from certain locations of the data storage in response to host read commands and using the saved data for subsequent garbage collection operations. The decision of whether to save data may be based on a number of criteria, including whether the data is located in an area of the data storage that is due to be garbage collected in the near future. In this manner, certain garbage collection operations can be performed without having to re-read the saved data.