STORAGE DEVICE, METHOD FOR CONTROLLING STORAGE DEVICE, AND PROGRAM - Patent application

Abstract

To provide a storage device capable of reducing occasions of erroneous detection of failure due to decrease in data transfer rate of a Shingled Magnetic Recording (SMR) type HDD, a method for controlling a storage device, and a program.SOLUTION: A method for controlling a storage device comprises: inspecting performance of at least one hard disk drive at a predetermined timing; and when detecting a hard disk drive determined to be in a performance deteriorated state according to a result of the inspection, selecting one of countermeasure actions mutually different depending on whether or not the hard disk drive determined to be in the performance deteriorated state is a SMR type hard disk drive, and executing the selected countermeasure action.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a storage device, a control method for a storage device, and a program. [Background technology]

[0002] In SMR (Shingled Magnetic Recording) hard disk drives (hereafter referred to as HDDs), if the usage rate of the internal cache becomes higher than a certain value (e.g., 80%, although this may vary from HDD to HDD), the data read and write speed (hereafter referred to as data transfer speed) may decrease even if the HDD itself is not faulty.

[0003] On the other hand, a controller of a NAS (Network Attacked Storage) or the like may monitor the data transfer speed of an HDD included in the NAS, and may determine that an HDD whose data transfer speed is lower than a predetermined standard is broken. For example, Patent Document 1 discloses a technique for determining a performance degradation of a storage device by calculating an average response time or the like based on the actual response time to a data access request for the storage device such as an HDD. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-190055 A Summary of the Invention [Problem to be solved by the invention]

[0005] If the above-mentioned SMR type HDD is used as the HDD of a NAS equipped with the above-mentioned conventional controller, when the data transfer speed decreases due to an increase in the internal cache usage rate of the HDD, the controller may mistakenly determine that the HDD is faulty, even if the HDD is normal.

[0006] If the NAS controller could directly obtain the internal cache usage rate of the HDD, it would be possible to determine whether the HDD has failed by referencing that internal cache usage rate, eliminating the above erroneous judgment. However, NAS controllers generally do not have a means of obtaining the internal cache usage rate of the HDD, and so it is currently not possible to obtain the internal cache usage rate of the HDD.

[0007] The present invention has been made in consideration of the above-mentioned situation, and one of its objectives is to provide a storage device, a control method for a storage device, and a program that can reduce the chance of misidentifying a failure due to a decrease in data transfer speed caused by an increase in the internal cache usage rate in an SMR type HDD, even in a situation where the internal cache usage rate of the HDD cannot be obtained. [Means for solving the problem]

[0008] One aspect of the present invention which solves the problems of the conventional examples described above is a storage device having a plurality of storage devices including at least one hard disk drive, comprising: inspection means for inspecting the performance of the hard disk drives at a predetermined timing; and execution means for selecting and executing a predetermined countermeasure processing when a hard disk drive is found to be in a state of degraded performance as a result of the inspection by the inspection means, wherein the execution means selects and executes different countermeasure processing depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive.

[0009] In this way, by taking different countermeasures measures for SMR type hard disk drives than for other hard disk drives, it is possible to reduce the chance of misidentifying a failure due to a decrease in data transfer speed caused by increased usage of the internal cache in an SMR type hard disk drive.

[0010] In addition, here, when the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive, the execution means may execute a notification process to notify that the hard disk drive is in a state of degraded performance.

[0011] This allows the user to know that the performance of the SMR type hard disk drive is degraded.

[0012] Furthermore, in this notification process, the user may be informed to wait for a period of time that has been experimentally determined in advance as the time it takes for the usage rate of the internal cache to drop by a specified percentage when the SMR type hard disk drive is left powered on but without writing to it.

[0013] Another aspect of the present invention is a method for controlling a storage device, using a computer connected to a plurality of storage devices including at least one hard disk drive, and carrying out the following steps: an inspection means inspects the performance of the hard disk drive at a predetermined timing; and an execution means selects and executes a predetermined corrective action when a hard disk drive is found to be in a state of degraded performance as a result of the inspection by the inspection means, and the execution means selects and executes different countermeasure actions depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive.

[0014] This also reduces the chance of a malfunction being mistakenly identified as occurring due to a decrease in data transfer speed caused by an increase in the usage rate of the internal cache in an SMR hard disk drive.

[0015] Yet another aspect of the present invention is a program for controlling a storage device having multiple storage devices including at least one hard disk drive, which functions as an inspection means for inspecting the performance of the hard disk drive at a predetermined timing, and an execution means for selecting and executing a predetermined countermeasure processing when a hard disk drive is found to be in a state of degraded performance as a result of the inspection by the inspection means, and when functioning as the execution means, different countermeasure processing is selected and executed depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive or not. Effect of the Invention

[0016] According to the present invention, it is possible to reduce the chance of a malfunction being mistakenly identified due to a decrease in data transfer speed caused by an increase in the usage rate of the internal cache in an SMR type HDD. [Brief description of the drawings]

[0017] [Figure 1] 1 is a block diagram illustrating an example of the configuration of a storage device and a host apparatus according to an embodiment of the present invention. [Diagram 2] 2 is a functional block diagram illustrating an example of a controller of a storage device according to an embodiment of the present invention. [Diagram 3] 4 is a flowchart illustrating an example of the operation of the storage device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] An embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a storage device 10 according to the present embodiment includes a plurality of HDDs 11 of either SMR (Shingled Magnetic Recording) type or CMR (Conventional Magnetic Recording) type as storage devices, or includes at least one SMR or CMR type HDD 11 and other storage devices such as SSDs, thus including a plurality of storage devices in total. The storage device 10 includes a controller 12, a display unit 13, and a communication unit 14, and is connected to a host device 20 via a communication means such as a network or a serial interface. As an example, the storage device 10 is a NAS or the like that configures a RAID (Redundant Array of Inexpensive Disks), and the host device 20 is a personal computer or the like.

[0019] In this embodiment, the controller 12 includes a program control device and a storage device such as a memory element. At least a part of this storage device is a non-volatile storage device, and the controller 12 executes a predetermined process according to a program stored in the non-volatile storage device. This storage device also operates as a work memory for the controller 12. The program stored in this storage device may be provided by being stored in a computer-readable and non-transitory recording medium.

[0020] In this embodiment, the controller 12 transmits and receives data to and from the host device 20 via the communication unit 14, and also receives instructions from the host device 20 to perform processes as a general storage device, such as writing and reading data.

[0021] The controller 12 of this embodiment may also function as a RAID controller. When the controller 12 functions as a RAID controller and meets a predetermined condition, such as when it is determined that the HDD 11 has failed, it performs processing such as stopping the use of at least a part of the HDD 11 (transition processing to a so-called degraded mode (degraded state)) and issuing a warning.

[0022] One of the features of this embodiment is that the controller 12 executes a performance inspection process for each of the multiple HDDs 11 at a predetermined timing, and when the result of this performance inspection process indicates that the performance of any of the HDDs 11 is degraded, the controller 12 selects and executes a predetermined countermeasure process. Here, in the countermeasure process, the controller 12 selectively executes different countermeasure processes depending on whether the HDD 11 determined to be in a degraded performance state is an SMR type HDD 11. A specific example of the operation of the controller 12 will be described later.

[0023] The display unit 13 is an LED lamp or the like, and displays and outputs information according to instructions input from the controller 12. The communication unit 14 is a network interface, a serial communication interface, or the like, and receives a data write instruction from the host device 20 via a network or a serial communication interface conforming to a standard such as USB (Universal Serial Bus), and outputs the instruction to the controller 12. The communication unit 14 also receives a data read instruction from the host device 20, outputs the instruction to the controller 12, and sends data output by the controller 12 in response to the instruction to the host device 20.

[0024] Next, a description will be given of an example of the operation of the controller 12. The controller 12 according to one example of the present embodiment is functionally configured to include a data processing unit 121, an inspection unit 122, and a countermeasure processing unit 123, as exemplified in FIG.

[0025] The data processing unit 121 receives instructions from the host device 20 via the communication unit 14, and writes data to the HDD 11, reads data from the HDD 11, and so on.

[0026] The inspection unit 122 operates at a predetermined timing, such as when the storage device 10 is started, and inspects the HDD 11. The inspection unit 122 inspects each of a plurality of storage devices, such as the HDD 11.

[0027] In one example of this embodiment, the inspection unit 122 acquires the data transfer rate of the HDD 11 and performs a performance inspection process. Specifically, this data transfer rate can be acquired by a process similar to the process of measuring the device reading rate in the hdparam command that is widely used in operating systems such as Linux. If the acquired data transfer rate is below a predetermined threshold, the inspection unit 122 determines that the inspected HDD 11 is in a state of performance degradation, and outputs information identifying the HDD 11 to the countermeasure processing unit 123.

[0028] In addition, in one example of this embodiment, the inspection unit 122 is not limited to a single performance inspection process, and may determine whether or not the HDD 11 being inspected is in a state of degraded performance based on the results of the performance inspection processes performed multiple times.

[0029] As an example, when the data transfer rate of the HDD 11 that is the target of the performance inspection process falls below a predetermined threshold, the inspection unit 122 performs a performance inspection process on the HDD 11 again, and when the data transfer rate of the HDD 11 in the second performance inspection process is still below the predetermined threshold, the inspection unit 122 performs a performance inspection process on the HDD 11 a third time, and when the data transfer rate of the HDD 11 falls below the predetermined threshold three times, the inspection unit 122 may determine that the performance of the HDD 11 is degraded. In this example, if the data transfer rate does not fall below the predetermined threshold even once out of a maximum of three performance inspection processes, the inspection unit 122 does not determine that the performance of the HDD 11 is degraded.

[0030] When the countermeasure processing unit 123 receives input of information specifying the HDD 11 determined to be in a performance degraded state from the inspection unit 122, the countermeasure processing unit 123 executes the following countermeasure processing.

[0031] Specifically, in one example of the present embodiment, the countermeasure processing unit 123 judges whether or not the HDD 11 specified by the information received from the inspection unit 122 is an SMR type HDD. If it is judged that the HDD 11 is an SMR type HDD, the countermeasure processing unit 123 selects and executes either a notification process (hereinafter, for the sake of distinction, referred to as SMR notification process) for notifying that the HDD 11 is in a performance degradation state, or a disconnection process of the HDD 11, which will be described later, if it is judged that the HDD 11 is not an SMR type HDD. The notification process of the SMR notification process may be performed, for example, by turning on or blinking the LED of the display unit 13 in a predetermined manner. The selectively executed process is not limited to the above-mentioned process. For example, if it is judged that the HDD 11 is not an SMR type HDD, the process (data processing) as a general storage device may be carried out without performing processes such as disconnection or notification.

[0032] Here, the determination as to whether the HDD 11 is an SMR type HDD or not may be made based on the model number of the storage device 10. Specifically, when a manufacturer assigns a specific model number to the storage device 10 equipped with an SMR type HDD, a list of storage devices equipped with an SMR type HDD including the specific model number is stored in advance in the storage device of the controller 12. Then, the countermeasure processing unit 123 acquires information on the model number of the storage device 10 in which it is built (this is also stored in advance in the storage device of the controller 12), and checks whether the acquired model number information is included in the list, thereby determining whether the HDD 11 is an SMR type HDD or not. However, an example of the process of determining whether the HDD 11 is an SMR type HDD or not is not limited to this example.

[0033] For example, the countermeasure processing unit 123 may acquire information on the model number of the storage device 10 in which it is built, and determine whether or not the HDD 11 is an SMR type HDD based on whether or not the acquired model number information matches a specific model number that the manufacturer assigns to storage devices equipped with SMR type HDDs (specifically, if the manufacturer assigns a model number starting with "SMR" to the storage device 10 equipped with an SMR type HDD, then the acquired model number information may be determined to start with "SMR").

[0034] In yet another example, flag information indicating whether or not the HDD 11 mounted on the storage device 10 is an SMR type HDD may be stored in advance in the storage device of the controller 12. In this example, the countermeasure processing unit 123 reads and refers to the flag information to determine whether or not the HDD 11 is an SMR type HDD.

[0035] Also, in this example, the model number information of the storage device 10 is referenced, but the present invention is not limited to this example, and the determination may be made based on the identification information of the HDD 11 itself obtained by the hdparm command or the like.

[0036] Furthermore, when the countermeasure processing unit 123 determines that the HDD 11 specified by the information received from the inspection unit 122 is not an SMR type HDD, it disconnects the HDD 11 as a prohibited state and starts operation in a so-called degraded mode. At this time, the countermeasure processing unit 123 may notify the fact by turning on or blinking the LED of the display unit 13 in a predetermined manner, but this notification is made different from the lighting or blinking manner in the SMR notification process so that the user can distinguish it.

[0037] [Operation] The storage device 10 of this embodiment has the above configuration and, as an example, operates as follows: When the storage device 10 is started, as shown in Fig. 3, it executes a performance inspection process for each of the HDDs 11 included in the storage device 10 (S11).

[0038] In this performance inspection process, if the acquired data transfer rate falls below a predetermined threshold, the storage device 10 retries the process of acquiring the data transfer rate up to a predetermined number of times (e.g., three times), and if any of the data transfer rates acquired the first time or during the retry exceeds the predetermined threshold, it determines that the performance is not degraded, and if all of the data transfer rates acquired the first time or during the retry fall below the predetermined threshold, it determines that the performance is degraded.

[0039] If the storage device 10 determines that the performance is degraded as a result of this determination (S12: Yes), it further determines whether the HDD 11 that has been subjected to the performance inspection process is an SMR type HDD (S13).

[0040] For example, if the model number information of the storage device 10 itself is included in a list of model numbers of products incorporating SMR type HDDs, the HDD 11 that has undergone the performance inspection process is determined to be an SMR type HDD.

[0041] If the storage device 10 determines that the HDD 11 that has been subjected to the performance inspection process is an SMR type HDD (S13: Yes), it performs an SMR notification process (S14) by turning on or blinking the LED on the display unit 13 in a predetermined manner (for example, by making the LED blink yellow).

[0042] On the other hand, if it is determined in step S13 that the HDD 11 that has undergone the performance inspection process is not an SMR type HDD (S13: No), the storage device 10 disconnects the HDD 11 as being in a disabled state and starts operating in a so-called degraded mode (S15). At this time, the storage device 10 may notify that it is operating in the degraded mode by turning on or blinking the LED of the display unit 13 in a manner different from the process in step S14 (for example, by keeping the LED lit in red).

[0043] The storage device 10 repeats the process of steps S11 to S15 for each HDD 11, and when it has completed the process of steps S11 to S15 for all HDDs 11, it completes the startup process and then performs processing (data processing) as a general storage device, such as receiving instructions from the host device 20 via the communication unit 14 and writing data to the HDD 11 and reading data from the HDD 11 (S16).

[0044] Thus, according to this embodiment, when it is determined that the performance of an HDD is in a degraded state, it is determined whether the type of HDD is an SMR type, and if the HDD determined to be in a degraded state is an SMR type HDD, the user can be notified that the performance of the SMR type hard disk drive is in a degraded state without disconnecting the HDD.

[0045] [Another example of a performance degradation notification] Furthermore, the notification of performance degradation is not limited to the example of being performed by blinking an LED on the display unit 13. For example, if the display unit 13 has a display capable of displaying characters, the controller 12 of the storage device 10 may guide the user to wait for a predetermined time with the SMR type HDD 11 in a powered state in the SMR notification process in step S14 above.

[0046] The specified time mentioned here is a time experimentally determined in advance as the time it takes for the usage rate of the internal cache to drop by a specified percentage when the SMR type HDD 11 is left powered on and no writing is performed on the HDD 11.

[0047] Furthermore, in the SMR notification process of step S14, the controller 12 may request the host device 20 to display a message informing the host device 20 that the performance of the SMR type HDD 11 is in a degraded state, or that the SMR type HDD 11 should be left powered on and wait for the above-mentioned specified period of time (request for SMR notification process).

[0048] In this case, upon receiving a request for the SMR notification process, the host device 20 displays at least one of a message to the user indicating that "the performance of the SMR type HDD 11 is in a degraded state" or that "the SMR type HDD 11 should be left powered on and wait for the above-mentioned specified period of time," and then executes the SMR notification process.

[0049] The SMR notification process guide may also include information on specific measures to be taken, such as "leave the HDD without writing anything to it for a certain period of time and then reboot the HDD."

[0050] [Performance degradation record] Furthermore, in this embodiment, when the storage device 10 determines that the performance of any of the SMR type HDDs 11 is degraded, it notifies the user of the performance degradation of that HDD 11 (SMR notification processing), but may also record information to the effect that the performance degradation has occurred in that SMR type HDD 11 (hereinafter referred to as performance degradation information) in a non-volatile memory device of the controller 12.

[0051] This performance degradation information may also include information on the date and time when the performance degradation information was recorded. If the storage device 10 is equipped with a calendar IC or the like (not shown), this date and time information may be obtained from the calendar IC, or may be obtained from the host device 20 or a network time server connected via a network.

[0052] When the date and time are recorded in this manner, the storage device 10 may notify the user that a predetermined time has elapsed since the recorded date and time (notification of time lapse). This notification of time lapse may be made by lighting or blinking an LED on the display unit 13, or by instructing the host device 20 to display information. The predetermined time is also set to a time experimentally determined in advance as the time at which the usage rate of the internal cache drops by a predetermined percentage (for example, 20%) when the SMR type HDD 11 is left in a powered state with no writing to the HDD 11, or a time longer than this.

[0053] The operation of recording this performance degradation may be performed by the host device 20. In this case, when the host device 20 receives information from the storage device 10 indicating that the performance of any of the SMR type HDDs 11 has been determined to be in a degraded state (such as a request for SMR notification processing), the host device 20 records that information (performance degradation information). In this case as well, the performance degradation information may include information on the date and time when the performance degradation information was recorded.

[0054] In this way, when the host device 20 records performance degradation information including date and time information, the host device 20 may notify the user when a predetermined time has passed since the recorded date and time (time lapse notification). Furthermore, in this case, a process may be performed to restrict data writing to the storage device 10 at the user's instruction until the time lapse notification is given. For example, when a data write instruction is given by the user between the time when the performance degradation information was recorded and the above-mentioned predetermined time has passed, the host device 20 displays to the user that "the HDD is in a performance degraded state" and controls so as not to write data according to the instruction.

[0055] In the above embodiment, the storage device 10 is described as having a plurality of HDDs, but the present invention is not limited to this and may have a plurality of storage devices. For example, the storage device 10 may have one HDD and one or more SSDs.

[0056] [Example of processing on the host side] Furthermore, in the above description of this embodiment, the operations of the inspection unit 122 and the countermeasure processing unit 123 are performed by the controller 12 of the storage device 10, but this embodiment is not limited to this example.

[0057] For example, the host device 20 may have these functional configurations. In this example, a program for causing the host device 20 to operate as the inspection unit 122 and the countermeasure processing unit 123 is installed in the host device 20.

[0058] The host device 20 then targets the HDD 11 among the disk devices connected to itself (whether the HDD 11 is built into the housing of the host device 20 or is in a storage device 10 externally attached to the host device 20) and inspects the performance of the HDD 11 at a predetermined timing (for example, when the storage device 10 is started up). In the following example of this embodiment, it is assumed that the host device 20 is connected to a storage device 10 equipped with at least one HDD 11.

[0059] In this case as well, the host device 20 operating as the inspection unit 122 performs a performance inspection process by acquiring the data transfer rate of the target HDD 11 using the hdparam command or the like. If the acquired data transfer rate falls below a predetermined threshold, the host device 20 determines that the inspected HDD 11 is in a state of degraded performance.

[0060] Furthermore, as in the case of processing in the controller 12, the host device 20 may perform a performance inspection process on the HDD 11 at least once, rather than performing a performance inspection process once, and determine whether the HDD 11 being inspected is in a state of degraded performance based on the results of the multiple performance inspection processes.

[0061] That is, when the data transfer rate of the HDD 11 that is the subject of the performance inspection process falls below a predetermined threshold, the host device 20 performs a performance inspection process on the HDD 11 again, and when the data transfer rate of the HDD 11 in the second performance inspection process is still below the predetermined threshold, the host device 20 performs a performance inspection process on the HDD 11 a third time, and when the data transfer rate of the HDD 11 falls below the predetermined threshold three times, the host device 20 may determine that the performance of the HDD 11 is degraded. In this example, if the data transfer rate does not fall below the predetermined threshold even once in a maximum of three performance inspection processes, the performance of the HDD 11 is not determined to be degraded.

[0062] When the host device 20 determines that at least one of the HDDs 11 of the storage device 10 is in a degraded state, it operates as a countermeasure processing unit 123 and determines whether the HDD 11 determined to be in a degraded state (referred to as a target HDD) is an SMR type HDD. Whether the target HDD is an SMR type HDD may be determined based on the setting of the model number of the storage device 10, as in the case of processing by the controller 12. The host device 20 may also determine for each disk device whether the disk device is an SMR type HDD based on the model number of the disk device, etc.

[0063] For example, the host device 20 may acquire information on the model number of the storage device 10 (for this purpose, the storage device 10 is assumed to have a function for outputting its own model number to the host device 20 in response to an inquiry), and by referring to the acquired model number information, determine whether or not the model number is the one assigned by the manufacturer of the storage device 10 to a storage device 10 equipped with an SMR type HDD according to a list or a predetermined pattern, and based on this determination, determine whether or not the target HDD is an SMR type HDD.

[0064] If the target HDD is an SMR type HDD, the host device 20 notifies the user that the target HDD is in a degraded performance state (SMR notification process). For example, the host device 20 lights up or blinks the LED on the display unit 13 of the storage unit 10 in a predetermined manner. The host device 20 may also display a message informing the user that the performance of the target HDD is degraded and / or that the user should wait for a predetermined period of time while keeping the target HDD of the storage device 10 powered on.

[0065] The specified time here is also a time experimentally determined in advance as the time at which the usage rate of the internal cache drops by a specified percentage when the SMR type HDD 11 is left powered on and no data is written to the HDD 11.

[0066] On the other hand, when the host device 20 determines that the target HDD is not an SMR type HDD, it instructs the storage device 10 to disconnect the target HDD as a prohibited state and to operate in a so-called degraded mode if there is a storage device other than the disconnected one. At this time, the host device 20 may notify the storage device 10 by turning on or blinking the LED on the display unit 13 of the storage device 10 in a predetermined manner. However, this notification at this time is made different from the lighting or blinking in the notification process of the SMR notification process so that the user can distinguish it. [Explanation of symbols]

[0067] 10 storage device, 11 HDD, 12 controller, 13 display unit, 14 communication unit, 20 host device, 121 data processing unit, 122 inspection unit, 123 countermeasure processing unit.

Claims

1. A storage device having a plurality of storage devices including at least one hard disk drive, a test means for testing the performance of the hard disk drive at a predetermined timing; an execution means for selecting and executing a predetermined corrective action when a hard disk drive determined to be in a degraded state of performance is found as a result of the inspection by the inspection means; The execution means selects and executes different countermeasure processes depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive.

2. 2. The storage device of claim 1, The execution means is a storage device that executes a notification process to notify that the hard disk drive determined to be in a state of degraded performance is in a state of degraded performance when the hard disk drive is an SMR type hard disk drive.

3. 3. The storage device of claim 2, In the notification process, the storage device guides the user to wait for a period of time that has been experimentally determined in advance as the period during which the usage rate of the internal cache of an SMR type hard disk drive will drop by a specified percentage when the drive is left powered on and no writing is being performed.

4. Using a computer connected to a plurality of storage devices including at least one hard disk drive, A step in which a testing means tests the performance of the hard disk drive at a predetermined timing; an execution means for selecting and executing a predetermined corrective action when a hard disk drive determined to be in a state of degraded performance is found as a result of the inspection by the inspection means; A control method for a storage device, wherein the execution means selects and executes different countermeasure processes depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive.

5. A program for controlling a storage device having a plurality of storage devices including at least one hard disk drive, a test means for testing the performance of the hard disk drive at a predetermined timing; an execution means for selecting and executing a predetermined corrective action when a hard disk drive determined to be in a degraded state is found as a result of the inspection by the inspection means; Function as a When functioning as the execution means, the program selects and executes different countermeasure processes depending on whether the hard disk drive determined to be in a state of degraded performance is an SMR type hard disk drive or not.

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