JP5002306B2 - Hard disk drive - Google Patents

Description

  The present invention relates to a hard disk drive, and more particularly, to a means for preventing data destruction that occurs in an adjacent track of an address with a high write frequency.

  Data writing to the hard disk is performed in units of addresses (sectors), and is performed by magnetizing the magnetic material at the accessed address. When data is written to one address, the magnetic flux leaks to the adjacent track of the track including the address, and therefore, writing is repeatedly performed to one address, and when the adjacent track is not written, the adjacent track gradually increases. In the worst case, the data recorded on the adjacent track may be destroyed. In this specification, the phenomenon that occurs due to the leakage of magnetic flux to the adjacent track is referred to as an ATI (Adjacent Track Interference) phenomenon.

  Conventionally, as a means for preventing the destruction of data due to this ATI phenomenon, the number of times a track on which data has been written is counted, and when the number of writes exceeds a threshold, A method of reading the recorded data and writing it again has been proposed (see Patent Document 1).

According to this method, the data of the adjacent track can be rewritten before the data is destroyed by the ATI phenomenon, so that the data can be prevented from being destroyed.
JP 2005-235380 A

  However, since the technique disclosed in Patent Document 1 must perform read / write processing to prevent data destruction due to the ATI phenomenon on both sides of a track with a large number of writes, the accessed track In addition, there is a problem that the access performance of the hard disk as viewed from the operating system is deteriorated because the head must be moved to the tracks on both sides thereof. In particular, even when the capacity of the hard disk increases, the data transfer speed of the hard disk and the time required for moving the head do not change much, so the problem becomes more prominent as the capacity and usage of the hard disk increase.

  The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a hard disk device capable of preventing data destruction due to the ATI phenomenon without significantly reducing the access performance of the hard disk. There is.

The present invention for solving the above problems, the first, example Bei address management portion between the hard disk and hard disk controller, the address management unit monitors the write count for each address, and the write count The data recorded at the address exceeding the threshold is replaced with another address on the hard disk, the correspondence between the replacement source address and the replacement destination address is stored, and the replacement source is stored from the hard disk controller. when the address is specified, the access to Ruha Dodisuku device to the address of the entering換先based on the correspondence between the address and the incoming換先address of said stored input 換元, the address management unit, The data recorded at the replacement source address where the number of write times exceeds the threshold is changed to the address where no data is recorded. After switching to the replacement destination address that can transfer the data at the highest speed, the data for one track following the next address of the replacement destination address is read, and the data for the read one track is the previous one. The writing is performed on one track following the address next to the rewriting destination address .

According to such a configuration, the data recorded at the address determined by the address management unit as having exceeded the threshold value is replaced with another address on the hard disk. Can be collected in a specific area on the hard disk. Therefore, it is possible to reduce the number of tracks adjacent to a track including an address with a large number of writes, to reduce the number of reads / writes to the adjacent track to prevent data destruction due to the ATI phenomenon, and to access the hard disk. A decrease in performance can be suppressed. In addition, since the address management unit manages the correspondence between the exchange source address and the exchange destination address, there is no inconvenience in reading or writing data. Furthermore, according to this configuration, the data recorded at the address determined by the address management unit as having exceeded the threshold value can be transferred at the highest speed among the addresses where no data is recorded. Thus, data can be written at a high speed at the time of replacement. In addition, since the read / write of the adjacent track to prevent data destruction due to the ATI phenomenon is performed only for one track following the address after the data is replaced, the number of head movements is reduced. And a decrease in hard disk access performance can be suppressed.

The present invention, in the second, the hard disk apparatus of the first configuration, the address management unit, the further manages saving area set on the hard disk, input to the write count exceeds the threshold After replacing the data recorded at the conversion source address with the replacement destination address that can transfer the data at the highest speed among the addresses where no data is recorded, from the address next to the replacement destination address Subsequently, the data for one track is replaced with the save area.

  According to such a configuration, since a non-data recording portion for one track can be provided below the data exchange destination address, it is unnecessary to read / write adjacent tracks to prevent data destruction due to the ATI phenomenon. can do.

The present invention, in the third, in the hard disk drive of the first or second configuration, the address management unit, the correspondence between the address and the address of the incoming換先of the entering換元, rather than the address units, a plurality It is configured to manage by address group unit consisting of a set of addresses.

  According to such a configuration, the capacity of the storage means for storing the correspondence between the exchange source address and the exchange destination address can be reduced, so that the cost of the hard disk device can be reduced.

The present invention, in the fourth, the hard disk apparatus of the first configuration, the address management unit, comprises a volatile memory for storing the write count for each said address, said address management unit, at power-on, the The number of writes for each address is read from the hard disk and written to the volatile memory, and the number of writes for each address stored in the volatile memory is read and written to the hard disk when the power is turned off.

  According to such a configuration, it is possible to reduce the cost of the hard disk device and to increase the data transfer speed as compared with the case where the address management unit includes a nonvolatile memory.

The present invention, in the fifth, the hard disk apparatus of the first or fourth configuration, the address management unit, comprises a volatile memory for storing the correspondence between the address and the address of the incoming換先of the entering換元The address management unit reads the correspondence between the exchange source address and the exchange destination address from the hard disk and writes it in the volatile memory when the power is turned on, and writes the exchange source address and the exchange destination address. When the correspondence with the address is updated, the updated correspondence is written to the hard disk.

  According to such a configuration, it is possible to reduce the cost of the hard disk device and to increase the data transfer speed as compared with the case where the address management unit includes a nonvolatile memory.

The present invention, in the sixth, the the hard disk apparatus of the first configuration, the address management unit, the intermittently to search for write count for each address, as a result of the search of the write count, the threshold When an address having a write count exceeding the value is searched, the data recorded in the address having the largest write count is sequentially replaced with another address on the hard disk.

  According to such a configuration, since data exchange for a plurality of addresses can be performed at once, as compared with the case where data exchange is performed whenever an address whose write count exceeds a threshold value occurs. The apparent access performance can be improved.

  In the hard disk device of the present invention, the address management unit monitors the number of writes for each address, and the data recorded at the address where the number of writes exceeds the threshold is replaced with another address on the hard disk. Data recorded at a high address can be collected in a specific area on the hard disk, and the number of adjacent tracks read / write can be reduced to prevent data corruption due to the ATI phenomenon. It is possible to suppress a decrease in hard disk access performance.

  An embodiment of a hard disk device according to the present invention will be described below with reference to FIGS. FIG. 1 is a configuration diagram of a hard disk device according to the embodiment, FIG. 2 is a flowchart showing a procedure of data replacement operation by the hard disk device according to the embodiment, and FIG. 3 is an example of a data replacement method by the hard disk device according to the embodiment. It is explanatory drawing shown.

  As shown in FIG. 1, the hard disk device of this example includes an access frequency counting device 10, a write frequency storage memory 11, an address conversion table updating device 20, and an address conversion table between a hard disk 50 and a hard disk controller 60. An address management unit 100 including a memory 21, an address translation device 30, a data exchange device 40, and a disk address stop device 70 is provided.

  As for the address of the hard disk 50, 0 address is assigned to the outermost periphery where the data transfer rate is the highest, and the final address is assigned to the innermost periphery where the data transfer rate is the lowest. Data transferred between the hard disk controller 60 and the hard disk 50 passes through the disk address stop device 70, the access count device 10, the address conversion device 30, and the data replacement device 40.

  The write count storage memory 11 stores the number of writes for each address in the hard disk 50, and its initial value is zero. As the write count storage memory 11, a non-volatile memory is used in order to prevent data loss when the power is shut off.

  The address conversion table memory 21 stores the correspondence between the replacement source address designated by the hard disk controller 60 and the corresponding replacement destination address when the data recorded on the hard disk 50 is replaced with another address. Therefore, in the initial state, the replacement source address designated by the hard disk controller 60 and the replacement destination address corresponding thereto are the same. As the address conversion table memory 21, a non-volatile memory is used in order to prevent the loss of data when the power is shut off.

  When there is no data replacement instruction from the address conversion table updating device 20, the data replacement device 40 transfers the data coming from the address conversion device 30 to the hard disk 50 as it is, and converts the data coming from the hard disk 50 as it is. Transfer to device 30. When there is a data replacement instruction from the address conversion table updating device 20, the data stored at the address where the data replacement instruction is issued is read and the data is written to the data replacement destination address. When the address conversion table update device 20 instructs to read / write data to the same address, the data stored at the address where the data replacement instruction is issued is read, and then the same address is read. The written data is written as it is.

  When the read / write access from the hard disk controller 60 to the hard disk 50 is continuously performed, the disk access stopping device 70 temporarily performs the next read / write access until the previous read / write access is completed. As a result, time-series read / write access to the hard disk 50 is enabled.

  The access count device 10 stores the write count for each address in the write count storage memory 11 and reads the write count for each address from the write count storage memory 11. When the write is executed for one address, the write count of the address stored in the write count storage memory 11 is incremented by one.

  The address conversion device 30 converts the address of the data transferred from the data replacement device 40 and the address of the data transferred from the access count counting device 10 and the replacement source and replacement stored in the address conversion table memory 21. Conversion based on the correspondence relationship of the previous address, recording of data at the replacement destination address corresponding to the replacement source address specified by the hard disk controller 60, and input corresponding to the replacement source address specified by the hard disk controller 60 Data can be read from the destination address.

  The address conversion table update device 20 stores a threshold value of the access count, reads the write count for each address from the write count storage memory 11, and the write count for one address exceeds the threshold value The data exchange device 40 is instructed to exchange data, and the correspondence relationship between the exchange source address and the exchange destination address stored in the address conversion table memory 21 is updated. The address conversion table update device 20 instructs the disk access stop device 70 to stop and restart access to the hard disk 50.

  The operation of the hard disk device configured as described above will be described below with reference to FIGS. The data exchange operation of this example is performed by an operation program stored in the hard disk controller 60, and it is characterized in that it is determined whether or not the number of writes exceeds a threshold value every specified period.

  When the hard disk controller 60 is activated, it waits for the specified period to elapse (procedure A10), and searches for an address whose write count exceeds the threshold (procedure A20). If there is an address whose write count exceeds the threshold value, the process proceeds to step A30, where the replacement destination address is designated as “address 0”, and access to the hard disk 50 is temporarily stopped (step A40). In this state, the address with the largest number of writes is stored in the exchange source address of the address translation table update device 20 (procedure A41), and the designated exchange destination address and the entry stored in the address translation table update device 20 are stored. The address conversion table stored in the address conversion table memory 21 is updated based on the conversion source address (procedure A42). Next, the data stored in the exchange source address is read, the data is recorded in the exchange destination address “0”, and the data exchange is executed (procedure A43). As a result, as shown in FIG. 3, the data recorded at the replacement source address n with the largest number of writes is replaced with the address 0 of the outermost track of the hard disk 50 that can perform the highest data transfer. Thereafter, the number of writes of the replacement source address is set to “0” (procedure A44), the value of the replacement destination address is increased by “1” (procedure A45), and access to the hard disk 50 is resumed (procedure A44). A46). The above operation is repeated until there are no more addresses where the number of writes exceeds the threshold (procedure A47).

  If there are no more addresses where the number of writes exceeds the threshold value, the process proceeds to step A50, the replacement destination address is incremented by 1, the data of the replacement destination address increased by 1 is read, and the same address is set. The read data is written. This procedure A50 is repeated until the outermost track of the hard disk 50 advances by one track. Finally, the write count storage memory 11 is initialized, and all the write counts stored therein are set to “0”. Thereby, as shown in FIG. 3, the data from the address 1 of the track 0 to the address 0 of the track 1 is rewritten to the same address.

  The hard disk device of this example replaces the data recorded at the address determined that the number of writes exceeds the threshold with the address having the highest access speed among the addresses where no data is recorded. Data can be written at high speed during replacement. In addition, the read / write of the adjacent track to prevent data destruction due to the ATI phenomenon can be performed for one track following the address after the data is replaced, so the number of head movements can be reduced. It is possible to reduce the decrease in hard disk access performance. In addition, since the address is searched at a predetermined number of times that exceeds the threshold value, it is possible to exchange data for a plurality of addresses all at once. The apparent access performance can be improved as compared with the case where data is exchanged whenever an address exceeding the threshold value is generated.

  In the above-described embodiment, a search is performed to determine whether there is an address whose write count exceeds the threshold value every specified period. Instead, whether the write count exceeds the threshold value is searched. It is also possible to always determine whether or not, and to replace the data and rewrite adjacent tracks each time an address whose number of writes exceeds the threshold is retrieved.

  In the embodiment, the data of the address whose write count exceeds the threshold value is replaced with the address of the outermost track, and then the adjacent track is rewritten. However, as shown in FIG. It is also possible to replace the data at the address exceeding the threshold with the address of the outermost track and then replace the data of the adjacent track with a predetermined save area p. According to such a configuration, since the non-data recording portion for one track or more can be provided at the replacement source of the data replaced with the save area p, adjacent tracks to be performed in order to prevent data destruction due to the ATI phenomenon. Read / write becomes unnecessary, and the total data transfer speed can be further increased.

  In the embodiment, the replacement source address and the replacement destination address are stored in the address conversion table memory 21 in units of addresses. Instead of such a configuration, the replacement source address and the replacement destination address are stored. Addresses can also be stored in units of address groups consisting of a set of addresses, for example, in units of tracks. According to such a configuration, the capacity of the address conversion table memory 21 can be reduced, so that the cost of the hard disk device can be reduced.

  Further, in the embodiment, the nonvolatile memory is provided as the write count storage memory 11 and the address conversion table memory 21, but a volatile memory may be provided instead of such a configuration. According to such a configuration, it is possible to reduce the cost of the hard disk device and to increase the data transfer speed as compared with the case where the address management unit includes a nonvolatile memory.

1 is a configuration diagram of a hard disk device according to an embodiment. It is a flowchart which shows the procedure of the data exchange operation | movement by the hard-disk apparatus which concerns on embodiment. It is explanatory drawing which shows an example of the data exchange system by the hard-disk apparatus which concerns on embodiment. It is explanatory drawing which shows the other example of the data replacement system by the hard-disk apparatus which concerns on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Access frequency count device 11 Write frequency memory 20 Address conversion table update device 21 Address conversion table memory 30 Address conversion device 40 Data exchange device 50 Hard disk 60 Hard disk controller 70 Disk address stop device 100 Address management part

Claims (6)

Bei example an address management portion between the hard disk and hard disk controller, the address management unit monitors the write count for each address, the hard disk data write count is recorded in the address exceeds the threshold In addition to replacing with the other addresses above, the correspondence between the replacement source address and the replacement destination address is stored, and when the replacement source address is designated from the hard disk controller, the stored replacement source in the address and the address of the incoming換先access to Ruha Dodisuku device to the address of the entering換先based on the correspondence of,
The address management unit is configured to replace the data recorded at the exchange source address where the number of write times exceeds a threshold with the exchange destination that can perform the highest data transfer among the addresses where no data is recorded. After switching to the address, the data for one track following the address next to the replacement destination address is read, and the data for the read one track continues from the address next to the replacement destination address. hard disk apparatus characterized by writing to. 2. The hard disk device according to claim 1, wherein the address management unit further manages a save area set on the hard disk, and is recorded at a replacement source address at which the number of writes exceeds a threshold value. Data is replaced with a replacement destination address that can transfer data at the highest speed among the addresses where no data is recorded, and the data for one track following the next address of the replacement destination address A hard disk device that is replaced with an evacuation area . In the hard disk device according to claim 1 or claim 2, wherein the address management unit, the correspondence between the address and the address of the incoming換先of the entering換元, rather than the address unit, the address comprising a set of a plurality of addresses A hard disk device that is managed in groups . The hard disk device according to claim 1 , wherein the address management unit includes a volatile memory that stores the number of writes for each address, and the address management unit writes the number of writes for each address from the hard disk when power is turned on. Is read out and written into the volatile memory, and when the power is shut off, the number of writes for each address stored in the volatile memory is read out and written into the hard disk. In the hard disk device according to claim 1 or claim 4, wherein the address management unit, comprises a volatile memory for storing the correspondence between the address and the address of the incoming換先the entering-換元, the address management unit, When the power is turned on, the correspondence between the exchange source address and the exchange destination address is read from the hard disk and written to the volatile memory, and the correspondence between the exchange source address and the exchange destination address is updated. A hard disk device that writes the updated response to the hard disk. 2. The hard disk device according to claim 1, wherein the address management unit intermittently searches for the number of writes for each address, and as a result of performing the search for the number of writes, the address of the number of writes exceeding the threshold is found. A hard disk device characterized in that, when retrieved, the data recorded at the address with the largest number of writes is sequentially replaced with another address on the hard disk.

Images