Disk device and recording method

A disk device that is controlled using system data, the disk device comprising:

• a disk;
• a non-volatile memory;
• a controller;
• and
• a volatile memory, wherein
• the controller is configured to record a set of system data on both the non-volatile memory and the disk,
• the controller is configured to execute system data write processing including processing for writing the set of system data to the non-volatile memory and processing for writing the set of system data to the disk, and
• the controller is configured to write the set of system data to the disk after writing the set of system data to the non-volatile memory in the system data write processing,
• the disk device is equipped with a power loss protection function of protecting at least a part of one or more sets of data recorded on the volatile memory by recording at least the part of the one or more sets of data on the non-volatile memory when supply of power to the disk device is stopped, and
• the controller is configured to, when the set of system data is updated:
• determine whether or not a size of the set of system data updated is equal to or smaller than a predetermined size that can be protected by the power loss protection function,
• store the set of system data updated in the volatile memory when the controller determined that the size of the set of system data updated is equal to or smaller than the predetermined size, and
• execute the system data write processing and write the set of system data updated to the non-volatile memory when the controller determined that the size of the set of system data updated is larger than the predetermined size.

A recording method for system data used to control a disk device including a disk and a non-volatile memory, the recording method comprising:

• recording a set of system data on both the non-volatile memory and the disk;
• executing system data write processing including processing for writing the set of system data to the non-volatile memory, processing for writing the set of system data to the disk, and writing the set of system data to the disk after writing the set of system data to the non-volatile memory;
• executing determination processing for determining whether or not processing based on a command received from a host device is being executed in the disk device before the set of system data is written to the disk in the system data write processing;
• writing at least the set of system data to the disk when it is determined in the determination processing that the processing based on the command is not being executed;
• and
• interrupting the system data write processing when it is determined in the determination processing that the processing based on the command is being executed.

A recording method for system data used to control a disk device including a disk and a non-volatile memory, the recording method comprising:

• recording a set of system data on both the non-volatile memory and the disk;
• and
• executing system data write processing including processing for writing the set of system data to the non-volatile memory and processing for writing the set of system data to the disk, wherein
• the system data write processing includes writing the set of system data to the disk after writing the set of system data to the non-volatile memory, and
• the disk device is equipped with a power loss protection function of protecting at least a part of one or more sets of data recorded on a volatile memory by recording at least the part of the one or more sets of data on the non-volatile memory when supply of power to the disk device is stopped,
• the recording method further comprises, when the set of system data is updated,
• determining whether or not a size of the set of system data updated is equal to or smaller than a predetermined size that can be protected by the power loss protection function,
• storing the set of system data updated in the volatile memory when it is determined that the size of the set of system data updated is equal to or smaller than the predetermined size, and
• executing the system data write processing and writing the set of system data updated to the non-volatile memory when it is determined that the size of the set of system data updated is larger than the predetermined size.