According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

According to one embodiment, a disk device includes a disk-shaped recording medium, a base accommodating the recording medium, the base including a bottom wall, a sidewall on a peripheral portion of the bottom wall, and a rib on a part of an upper surface of the sidewall and extending along an entire circumference of the sidewall, a first cover on a part of the upper surface of the sidewall, and a second cover on a first surface of the rib and above the first cover. The rib includes a first region with a first width, a second region with a second width less than the first width, and the first surface with a fixed width around an entire circumference of the rib. The first region and the second region are located corresponding to a side portion of the recording medium.

According to one embodiment, a magnetic disk device incudes a first magnetic disk, a first actuator that reads/writes data from/to the first magnetic disk, a first controller that controls the first actuator, a second magnetic disk, a second actuator that reads/writes data from/to the second magnetic disk, a second controller that controls the second actuator, wherein the first controller executes read/write processing, and the second controller stores trace data of the read/write processing when the first controller executes the read/write processing.

Host data to be written to a recording medium is categorized as one of sequential data or random data. The sequential data is written to a first track width on the recording medium. The random data is written to a second track width on the recording medium, the second track width being larger than the first track width.

According to one embodiment, a monitoring unit of a magnetic disk device monitors a supply voltage supplied to a plurality of actuators by a first threshold value at which power supply by back electromotive force of a motor is started, and a second threshold value that is larger than the first threshold value. In a case where the supply voltage is lower than or equal to the second threshold value and is higher than the first threshold value, a controller interrupts execution of processing of reading/writing data to a magnetic disk in at least one of the actuators according to a predetermined condition based on execution status of the processing in the actuators.

According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

Systems and methods are disclosed for dynamically adjusting parameters used during a read operation to reduce stress on a read head. In certain embodiments, an apparatus may comprise a read head configured to read data stored to a data storage medium, and a control circuit that controls a parameter of the read head influencing the read head's ability to accurately read data. The control circuit may be configured to extend the working lifespan of the read head by monitoring a read performance of the read head, and adjusting the parameter to reduce the read performance when the read performance is greater than a first threshold.

According to one embodiment, a disk device includes a disk-shaped recording medium, a base accommodating the recording medium, the base including a bottom wall, a sidewall on a peripheral portion of the bottom wall, and a rib on a part of an upper surface of the sidewall, a first cover on a part of the upper surface of the sidewall, and a second cover on a first surface of the rib and above the first cover. The rib includes a first region with a first width, a second region with a second width less than the first width, and the first surface with a fixed width around an entire circumference of the rib. The first region and the second region are located corresponding to a side portion of the recording medium.

According to one embodiment, a magnetic disk device incudes a first magnetic disk, a first actuator that reads/writes data from/to the first magnetic disk, a first controller that controls the first actuator, a second magnetic disk, a second actuator that reads/writes data from/to the second magnetic disk, a second controller that controls the second actuator, wherein the first controller executes read/write processing, and the second controller stores trace data of the read/write processing when the first controller executes the read/write processing.

According to one embodiment, a disk device includes two magnetic disks opposing each other at intervals of 1.2 to 1.5 mm, and at least two suspension assemblies movable respectively between the two magnetic disks. Each of the suspension assemblies includes a base plate, a load beam extending from the base plate, a tab extending from a distal end of the load beam, a wiring member on the load beam and the base plate, including a gimbal portion, and a magnetic head on the gimbal portion, abutting on a dimple of the load beam via the gimbal portion. The ratio of a distance from a bendable location of the load beam to a center of the dimple with respect to a distance from the center of the dimple to a tip of the tab is 2.8 to 3.8.