According to one embodiment, there is provided a hard disk drive including a first recording surface, a second recording surface, a first magnetic head, a first actuator and a second actuator that move the first magnetic head, a second magnetic head, a third actuator and a fourth actuator that move the second magnetic head, a fifth actuator that moves the second actuator and the fourth actuator, a drive circuit that implements at least one of a first mode in which the second actuator and the fourth actuator operate differently from each other or a second mode in which the first and third actuators operate differently from each other, and a controller that controls the drive circuit.

A tape may be mounted into a tape drive. Mounting the tape into the tape drive may include loading the tape from a storage slot. The tape drive may request a first record of the tape from a tape storage subsystem. The tape drive may determine whether the first record of the tape exists in the tape storage subsystem. The tape drive may load the first record of the tape in random access memory (RAM) of the tape drive. The first record may include one or more data entries. The tape drive may append a new data entry to the first record. The first record may be transitioned to a second record upon being appended with the new data entry. The tape may be unmounted from the tape drive.

According to one embodiment, when adjusting a position of a magnetic head by a microactuator, in a case where a difference of an absolute value of a first voltage value obtained by correcting a voltage value applied to the microactuator based on hysteresis and an absolute value of a second voltage value obtained by not correcting the voltage value applied to the microactuator based on the hysteresis is positive, a control unit applies a third voltage value obtained based on the second voltage value to the microactuator, and adjusts shortage of the adjustment executed by the microactuator by controlling at least one of a voice coil motor and/or a microactuator other than a microactuator applying a third voltage value.

According to one embodiment, a magnetic disk device includes a disk, a head that writes data to the disk and reads data from the disk, an actuator that is rotationally driven and controls movement of the head mounted on the disk, and a controller that estimates a fundamental frequency of a position error signal generated in positioning control of the head, the fundamental frequency corresponding to a disturbance having harmonics, determines the fundamental frequency, determines the number of delay samples based on the fundamental frequency, and suppresses a multiplied frequency that is a harmonic of the fundamental frequency according to the number of the delay samples.

Motion of a first actuator in a multi-actuator drive is prevented from affecting a second actuator in the drive or from being affected by the second actuator. A coupling coordinator generates a hold command for the second actuator based on an operation to be carried out using the first actuator, where the hold command is generated before commands to carry out the operation are issued. The hold command may cause an aggressor actuator in the drive to halt a disturbance-generating operation being performed by the aggressor actuator or delay initiation of such an operation that is to be performed by the aggressor actuator. The hold command may cause a victim actuator in the drive to pause the execution of a sensitive operation being performed by the victim actuator or delay initiation of such an operation that is to be performed by the victim actuator.

A plurality of configuration sets are used with a detector coupled to a decoder. A processor is coupled to the memory registers and the detector and operable to load a first one of the configuration sets into the detector. The detector to attempts detection of the bits in the digital stream for a first iteration between the detector and the decoder using the first configuration set. After the first iteration, a second one of the configuration sets is loaded into the detector. The second configuration set is different than the first configuration set. The detector to attempts detection of the bits in the digital stream for a second iteration between the detector and the decoder using the second configuration set.

An exemplary data storage device includes an actuator arm assembly, a top guide rail, a bottom guide rail, and a first ball bearing. The actuator arm assembly includes a first post defining a pivot axis that is inclined between about 5 degrees and about 25 degrees from a horizontal plane defined by a data storage disk surface. The top guide rail includes a first rolling surface that is parallel to the pivot axis. The bottom guide rail is spaced from the top guide rail and includes a second rolling surface that is parallel to the first rolling surface. The first ball bearing includes a first inner race and a first outer race, the first inner race surrounding the first post, and the first outer race in contact with the first rolling surface or the second rolling surface. An exemplary method of assembling a data storage device is also described.

According to one embodiment, a magnetic disk device includes a magnetic disk, a spindle motor, a magnetic head, a ramp load mechanism, a filter, and a control section. The control section rotates the spindle motor at a second rotating speed for a given period of time at startup of the device, and then loads the magnetic head from the ramp load mechanism to a prescribed position on the magnetic disk. The second rotating speed is higher than a first rotating speed at which the spindle motor is rotated at the magnetic head reads/writes data from/to the magnetic disk.

A data storage device can have one or more rotating data media with data tracks that are radially disposed from a central spindle. The data tracks may be logically divided into multiple regions while a write strategy is generated with a region module to set a sequence of different regions for future data writes. Receipt of a data write request to the data storage media from a host can prompt the region module to classify the data write request as a sequential or random write in order to intelligently select a region to satisfy the data write request based on the write strategy to maximize data writing consistency for data associated with the data write request.

Technologies are provided for supporting multi-actuator storage device access using logical addresses. Separate sets of logical addresses (such as logical block addresses) can be associated with different actuators of a storage device. For example, a first set of logical addresses can be assigned to storage locations on one or more storage media that is/are accessible using a first actuator of the storage device and a second set of logical addresses can be assigned to storage locations on one or more storage media that is/are accessible using a second actuator of the storage device. The storage device can receive a data access request containing a logical address and can identify a logical address set to which the logical address belongs. The storage device can use an actuator associated with the logical address set to access a storage location assigned to the logical address.