Western Digital Technologies, Inc.

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Netherlands B.v.

International Business Machines Corporation

Other

David Robison Hall

Jonathan Darrel Coker

Adam Michael Espeseth

Gregory Michael Frees

Daniel Jonathan Auerbach

Kexiu Liu

Jeffrey Joesph Dobbek

Stephanie Louise Aho

Kuang Yang Tu

Jenghung Chen

Zarko Popov

Shad Henry Thorstenson

Andrew Larson

Maile Matsui Vasoli

Eran Sharon

Omer Fainzilber

Bernd Lamberts

Stella Achtenberg

Remmelt Pit

Paul Edward Movall

Mark A Steele

Wayne Howard Vinson

Richard Greenberg

Kris Victor Schouterden

Scott E Burton

David James Stanek

Nyles Heise

Clark A Anderson

Jeffrey L Furlong

Cory J Peterson

Prakash Balasubramaniam

James R Shipman

Lynn Charles Berning

Anthony Edwin Welter

Louise Ann Marier

Ali Khalili

Mark Andrew Jerde

Curtis Adam Harper

James Joseph Mosser

Steven Glenn Smith

John Helmy Shaker Marcos

Ali Sam Khalili

Gilat Flaishman

Andy Larson

Shad Thorstenson

Alice Louise Kub

Controlling a shingled magnetic recording (SMR) hard drive involves writing, to a first track of a zone pre-sized based on a nominal track width based on an expected mean track width across an entire zone, a portion of a write operation according to the nominal track width. Then, based on the positional accuracy of the first track writing, determining a second track position for an adjacent second track, and writing the second track another portion of the write operation according to the determined second track position. Thus, the determination and position of a given track is determined by the positional accuracy of a previously written track, considering for example the position error signal corresponding to the writing of the previously written track. Thus, the track pitch is effectively defined by the average positional error across a zone rather than by a worst-case scenario positional error across the zone.

Dynamic track pitch in shingled magnetic recording hard disk drive

Data is written in tracks in a first sub-region of a region of a disk using Shingled Magnetic Recording (SMR). It is determined whether a predetermined data storage capacity for the region can be reached by adding a sub-region guard band and shingle writing throughout a remaining portion of the region using a lower limit of track overlap. The sub-region guard band does not store data and separates the first sub-region from a second sub-region in the region. In response to determining that the predetermined data storage capacity for the region can be reached by adding the sub-region guard band and shingle writing with the lower limit of track overlap throughout the remaining portion of the region, the sub-region guard band is added, and the second sub-region is shingle written with at least as much track overlap as the lower limit of track overlap.

Adjustable sub-regions for shingled magnetic recording

Various illustrative aspects are directed to a data storage device, comprising one or more disks; at least one actuator mechanism configured to position at least a first head proximate to a first disk surface and a second head proximate to a second disk surface; and one or more processing devices. The one or more processing devices are configured to: assign logical tracks to physical tracks of the disk surfaces such that a respective logical track comprises: at least a portion of sectors of a primary physical track, the primary physical track being on the first disk surface; and at least a portion of sectors of a donor physical track, the donor physical track being on the second disk surface. The one or more processing devices are configured to perform, using the first head and the second head, a data access operation with at least one of the logical tracks.

Data storage device with flexible logical tracks and radius-independent data rate

A multiple-actuator hard disk drive includes a first actuator associated with a first logical unit and configured to operate on a first set of disk surfaces, a second actuator associated with a second logical unit and configured to operate on a second set of disk surfaces greater than the first set, and a controller accessing a mapping of logical memory addresses to physical memory locations. The mapping maps the first logical unit to the physical memory locations of the first set of surfaces and a parasitic portion of the second set of surfaces, and maps the second logical unit to the physical memory locations of the second set of surfaces exclusive of the parasitic portion of the second set of surfaces. Thus, data transfer commands performed on the parasitic portion are executed by one actuator while credit is given to the logical unit associated with the other actuator.

Parasitic commands for equalizing logical unit capacity in asymmetric multiple actuator hard disk drive

A data storage device is disclosed comprising a head actuated over a disk, a first semiconductor memory (SM) having a first endurance, and a second SM having a second endurance lower than the first endurance. A write command is received from a host including write data. When a size of the write command is less than a threshold, the write data is stored in a first SM write cache in the first SM, and when the size of the write command is greater than the threshold, the write data is stored in a second SM write cache in the second SM.

Data storage device managing low endurance semiconductor memory write cache

A Data Storage Device (DSD) includes a memory for storing data, and a controller configured to execute firmware or code to perform a task. While performing the task, the controller is further configured to assign unique identifiers to respective firmware or code portions that are executed to perform the task, and create a list or data structure including the unique identifier assigned to the firmware or code portion that created the task. A unique identifier is added to the list or data structure for each firmware or code portion executed for the task. The list or data structure indicates the order in which the firmware or code portions are executed.

Exception analysis for data storage devices

A data storage device includes a hard disk drive coupled to a printed circuit board (PCB), a volatile memory device coupled to the PCB, a non-volatile memory device coupled to the PCB, and a controller coupled to the PCB, such that the controller is in communication with the hard disk drive, the volatile memory device, and the non-volatile memory device. The controller is configured to identify patterns and/or structures of metadata for the hard disk drive, perform one or more of the following to the metadata to tailor the metadata: data shaping, content aware decoding, adaptive data trimming, and/or adaptive metablock sizing, and write the tailored metadata to the non-volatile memory device. The metadata is at least one of repeatable run out metadata, positioning error signal metadata, adjacent track interference metadata, and/or emergency power off metadata.

Methods for writing HDD metadata in NAND flash

A data storage device is disclosed comprising a head actuated over a disk comprising a plurality of data tracks. A plurality of access commands including a plurality of write commands are stored in a command queue, and the access commands are sorted into an execution order. A first write command is selected from the command queue based on the execution order, and a first part of the first write command is executed leaving a runt write command. The runt write command is executed between two of the sorted access commands so that the runt write command does not affect the execution order.

Data storage device executing runt write commands as free commands

A data storage device is disclosed comprising a plurality of disk surfaces, a first plurality of heads actuated over a first subset of the disk surfaces by a first actuator, and a second plurality of heads actuated over a second subset of the disk surfaces by a second actuator. A first access command is executed using the first actuator and a second access command is executed using the second actuator. When the first access command finishes before the second access command finishes, a third access command is selected to execute using the first actuator based on a time remaining (To) to finish the second access command, and at least part of the second access command is executed while concurrently executing at least part of the third access command during To

Data storage device seeking multiple actuators to improve performance

A data storage device is disclosed comprising a first plurality of heads actuated over a first subset of disk surfaces by a first actuator, and a second plurality of heads actuated over a second subset of disk surfaces by a second actuator. A plurality of access commands is received, wherein each access command is associated with one of the heads. A scalar is configured for each access command based on at least one of a current radial location of the corresponding head or a target radial location of the corresponding head associated with executing the access command. The access commands are sorted based on the scalars, and one of the access commands is selected for execution based on the sort.

Data storage device sorting access commands based on current or target location of heads

A data storage device is disclosed comprising a head actuated over a non-volatile storage medium. A plurality of access commands are received from a host and sored in a host queue and a pending queue. A first access command is selected from the host queue, wherein the first access command having a first execution time needed to execute the first access command. When a second access command in the pending queue can be executed within the first execution time, the second access command is executed, and after executing the second access command, the first access command in the host queue is executed. After selecting the first access command from the host queue, a third access command is transferred from the pending queue to the host queue based on a first-in-first-out (FIFO) order of the pending queue.

Data storage device executing access commands based on leapfrog sort

A data storage device is disclosed comprising a first head connected to a distal end of a first actuator arm, a second head connected to a distal end of second first actuator arm, a first coupler configured to couple the first actuator arm to an actuator, and a second coupler configured to couple the second actuator arm to the actuator. Access commands stored in a command queue are sorted into an execution order based on a selective coupling of the first and second actuator arms to the actuator. At least one of the access commands is executed based on the execution order in order to access at least one of a first and second disk surfaces using at least one of the first and second heads.

Data storage device coupling/decoupling actuator arm to/from an actuator

A data storage device is disclosed comprising a non-energy assist (NEA) head configured to access a first disk surface, and an energy assist (EA) head configured to access a second disk surface. The data storage device further comprises control circuitry configured to write data to the first disk surface, and migrate at least part of the data to the second disk surface.

Data storage device migrating data from non-energy assist disk surface to energy assist disk surface

Growing community of inventors

Rochester, MN, United States of America

David Robison Hall