JP2012243339A - Magnetic tape unit, data rearrangement method for magnetic tape and its program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve effective use of an idle capacity on a magnetic tape by efficiently rearranging valid data stored on the magnetic tape in a distributed manner to a determined place in a short time.SOLUTION: A magnetic tape unit has a unit body including a magnetic head 12 for moving in the width direction of a magnetic tape 11 reciprocatingly traveling so as to read/write data for each lap on the magnetic tape and a main control part 14 for controlling the magnetic head operation and the reading or writing operation. The unit body has a rearrangement management part 15 for instructing the main control part 14 to perform each control operation and to rearrange the data on the magnetic tape. Together with the rearrangement management part 15, an index storage part 16 for storing index information of the data is provided. The rearrangement management part 15 includes a rearrangement determination part 15A for determining whether each data is valid data on the basis of the index information and a rearrangement execution instruction part 15B for instructing the main control part 14 to rearrange the data when it is valid data.

Description

  The present invention relates to a magnetic tape device, a data relocation method for a magnetic tape, and a program thereof, and more particularly, a magnetic tape device, a data relocation method for a magnetic tape, and a program thereof capable of effectively utilizing free space. About.

In general, the types of data handled by a computer system are roughly classified into two types. One of them is structured data that can be managed as a database, and the other is unstructured data related to a file base such as documents, e-mails, photographs, and videos.
Here, recently, the data handled on a file basis has increased remarkably, and the storage for storing the data has been increasing in capacity. The magnetic tape device is no exception and its capacity is increasing.

  On the other hand, the magnetic tape in the magnetic tape device is a storage for sequentially accessing data, and there is no information corresponding to the file system. For this reason, file access cannot be handled directly from file-based applications, and is performed using dedicated magnetic tape management software, which is inconvenient for handling files compared to storage with a file system such as a hard disk. It was.

  Therefore, in recent years, a linear tape file system (LTFS: Linear Tape File System) in which a file system is constructed by dividing a partition on a magnetic tape in order to handle data on the magnetic tape as a file has been proposed.

  This linear tape file system (LTFS) is constructed by building file structure information such as file position, file attribute, directory structure, etc., and the main body of the file in separate partitions, and this file system is used. This makes it possible to directly access a file from a file-based application on a magnetic tape, and the handling of the file has become easier.

  In a file system related to a magnetic tape, an index partition (INDEX partition) that records file configuration information (hereinafter referred to as “index (INDEX)”) such as a file position, file attributes, and directory structure on a single magnetic tape has been conventionally used. And a data partition (DATA partition) for recording the main body of the file.

  When the file is updated, the index on the INDEX partition is overwritten with the latest index, but the file body is additionally written to the DATA partition. Therefore, by repeating the update of the file, the free space of the DATA partition (data) is reduced, and finally the free space is lost.

In this case, for example, LTFS (Linear Tape File System), which is one of file systems, cannot write to a magnetic tape, and a method of reformatting is used to reuse the magnetic tape.
As described above, in the magnetic tape file system, unnecessary files that are no longer referred to have been a cause of squeezing the free space.

Conventionally, Patent Documents 1 to 3 below are known as methods for removing such unnecessary files.
Among them, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2006-113938), only necessary data is read from a recording medium using a host device, reconstructed with only necessary data, and written back to the recording medium. A method for removing data is disclosed.

  Patent Document 2 (Patent No. 4079244) and Patent Document 3 (Patent No. 4402103) disclose a method of handling a plurality of media as one continuous recording area and rearranging additionally recorded data. ing

JP 2006-113938 A Patent No. 4079244 Japanese Patent No. 4402103

  However, in the method disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2006-113938), necessary data is sequentially read from the logical head of the recording medium recognized by the host device. When necessary data is distributed over the entire surface of the recording medium, it takes time to reach the recording position of the necessary data, and as a result, it takes time to reconstruct.

  In addition, since the reconstruction is performed by the host device, it is necessary to consider the data transfer time to the host device and the buffer used for the reconstruction process, for example, when the amount of data to be reconstructed increases. Inconveniences such as an increase in data transfer time according to the amount of data and an increase in prepared buffers occur.

  Further, in Patent Document 2 (Patent No. 4079244) and Patent Document 3 (Patent No. 4402103), as described above, a plurality of media are handled as one continuous recording area. However, since the data cannot be rearranged, the above problem in the file system of the magnetic tape cannot be solved yet.

(Object of invention)
The present invention improves the above-mentioned disadvantages of the related art, and effectively relocates valid data distributed and stored on the magnetic tape in a short time, thereby reducing the free space on the magnetic tape. It is an object of the present invention to provide a magnetic tape device, a magnetic tape data relocation method, and a program thereof that can be effectively used.

  In order to achieve the above object, a magnetic tape device according to the present invention moves in the width direction of a magnetic tape traveling in the forward direction or the backward direction and reads data for each of a plurality of laps set on the magnetic tape. An apparatus main body comprising a magnetic head that performs writing, and a main control unit that controls the movement operation of the magnetic head via a head drive mechanism and controls the reading or writing operation by the magnetic head based on an external command It has.

The apparatus body is provided with a rearrangement management unit that commands the main control unit to perform each control operation of the main control unit and commands rearrangement of data stored in the magnetic tape,
The rearrangement management unit is provided with an index storage unit that prestores data stored in the magnetic tape and index information of the index.

  Then, the relocation management unit re-determines whether or not each corresponding data is valid data that conforms to a preset relocation availability determination criterion based on the index information stored in the index storage unit. Relocation that instructs the main control unit to perform relocation for each data determined to be relocatable by the relocation determination unit and the relocation determination unit, and sets the relocation position of each data individually And an arrangement execution command unit.

  In order to achieve the above object, the data rearrangement method according to the present invention moves the operation position in the width direction of the magnetic tape traveling in the forward direction or the backward direction, and transfers data for each lap set on the magnetic tape. A magnetic head that performs reading or writing, and a main control unit that controls the moving operation of the magnetic head via a head drive mechanism and controls the reading or writing operation by the magnetic head based on an external command. In the magnetic tape device, the main control unit is operated according to a command from a rearrangement management unit equipped in advance, and is a data rearrangement method for executing rearrangement of data stored in the magnetic tape,

The rearrangement management unit reads the attribute and arrangement position of each data recorded on the magnetic tape by reading from an index storage unit equipped in advance with an index of each data concerning a plurality of files recorded on the magnetic tape. Check each file (data file confirmation process)
The relocation determination unit of the relocation management unit determines whether each corresponding data based on the index information stored in the index storage unit is valid data that conforms to a preset relocation availability determination criterion. Judgment (relocation possibility judgment process),
For each effective data determined to be rearrangeable by the rearrangement determination unit, the rearrangement execution command unit instructs the rearrangement execution command to the main control unit, and individually sets the rearrangement position of the data. The configuration of setting (relocation execution command process) is adopted.

Furthermore, in order to achieve the above object, the data relocation operation control program according to the present invention moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction, and sets a plurality of data set on the magnetic tape. A magnetic head for reading or writing data to each lap, and a main control for controlling the movement operation of the magnetic head via a head drive mechanism and controlling the reading or writing operation by the magnetic head based on an external command A magnetic tape device having a device body with a portion,
The apparatus main body is provided in advance with a rearrangement management unit that commands the main control unit to perform the control operations of the main control unit and rearranges data stored on the magnetic tape. Yes,

The index of each data concerning a plurality of files recorded on the magnetic tape is read from an index storage unit separately equipped in advance, and the attribute and arrangement position of each data recorded on the magnetic tape are confirmed for each file. Index confirmation processing function,
A relocation availability determination processing function for determining whether each of the corresponding data based on each index information stored in the index storage unit meets a preset relocation availability determination criterion;
Relocation execution for instructing the main control unit to perform relocation for each data determined to be relocatable by the relocation determination processing function and individually setting the relocation position of each data Command function,
These are realized by a computer provided in the rearrangement management unit.

  Since the present invention is configured as described above, according to this, a file (data) distributed in a plurality of wraps on a magnetic tape traveling in a forward direction or a return direction is distributed to a plurality of wraps on the magnetic tape. Since the read / write operation can be performed by switching the magnetic head in the width direction of the magnetic tape without stopping the tape movement operation (while switching the wrap), the file can be rearranged. Thus, even if the files are dispersed, an excellent magnetic tape device and magnetic tape that can relocate a file (data) in the time of two reciprocating operations including the erasing of the file at the relocation destination wrap Data rearrangement method and its program can be provided.

1 is a block diagram showing a first embodiment of a magnetic tape device according to the present invention. It is explanatory drawing which shows the structure of the rearrangement management part which comprises a part of 1st Embodiment disclosed in FIG. It is explanatory drawing which shows the structure of the main control part which comprises a part of 1st Embodiment disclosed in FIG. 3 is a flowchart illustrating an example of an operation of a rearrangement management unit disclosed in FIG. 2. 3 is a flowchart illustrating an example of an operation of a rearrangement determination unit included in the rearrangement management unit disclosed in FIG. 2. It is a flowchart which shows the rearrangement operation | movement which a main control part performs based on the instruction | command of the rearrangement execution command part which the rearrangement management part disclosed in FIG. 2 has. It is explanatory drawing which shows the structure division content of the data partition in the magnetic tape of 1st Embodiment disclosed in FIG. It is explanatory drawing which shows the example in case valid data is arrange | positioned and memorize | stored in the data partition disclosed in FIG. It is explanatory drawing which shows the example at the time of rearranging each effective data disclosed in FIG. FIG. 10A is a diagram illustrating an example of an arrangement state of valid data that can be rearranged when the back read function is added to the magnetic tape device disclosed in FIG. 1, and FIG. 10A is the same for the first wrap and the second wrap; FIG. 10B is an explanatory diagram showing an example in which valid data in the state shown in FIG. 10A is rearranged. It is a block diagram which shows 2nd Embodiment of the magnetic tape apparatus concerning this invention. It is explanatory drawing which shows the structure of the rearrangement management part which comprises a part of 2nd Embodiment disclosed in FIG. It is explanatory drawing which shows the structure of the main control part which comprises some 2nd Embodiment disclosed in FIG. It is a flowchart which shows operation | movement of the rearrangement determination part of the rearrangement management part disclosed in FIG. It is a flowchart which shows the rearrangement operation | movement which a main control part performs based on the instruction | command of the rearrangement execution command part which the rearrangement management part in 2nd Embodiment disclosed in FIG. 11 has. FIG. 16 is a diagram showing a data partition of a magnetic tape that forms part of the second embodiment disclosed in FIG. 11, and FIG. 16A is an explanatory diagram showing an example in which valid data before rearrangement is arranged, FIG. FIG. 16B is an explanatory diagram showing the arrangement of valid data after rearrangement. It is explanatory drawing which shows the example of the arrangement | positioning state of the effective data which enables the rearrangement at the time of adding a back read function to the magnetic tape device of 2nd Embodiment disclosed in FIG.

[First Embodiment]
The present invention is characterized in that in a linear recording type magnetic tape apparatus, data distributed in a plurality of wraps is rearranged with a small amount of tape reciprocation.
A first embodiment of the present invention will be described below with reference to FIGS.
First, the basic configuration contents of the magnetic tape device according to the first embodiment will be described, and then specific implementation contents will be described.

  Here, the files (data) to be rearranged in the first embodiment are files that are referred to by the latest index (INDEX) recorded in the INDEX partition, which will be described later, and these are valid files (valid data). ).

  In FIG. 1, the magnetic tape device 2 moves a working position in the width direction of a magnetic tape 11 that travels in the forward direction or the backward direction, and a plurality of laps 11 a, 11 b, 11 c set on the magnetic tape 11. The magnetic head 12 for reading or writing data to (see FIG. 7), the movement operation of the magnetic head 12 is controlled via the head drive mechanism 13, and the read or write operation by the magnetic head 12 is externally commanded. The apparatus main body 2A provided with the main control part 14 controlled based on this is provided.

  Reference numeral 11A denotes a magnetic tape traveling drive mechanism that operates under the control of the main control unit 14 and drives the above-described magnetic tape 11 freely in its forward or backward direction. Reference numeral 18 denotes an input unit for externally inputting necessary information and commands to the main control unit 14.

Further, the apparatus main body 2A is instructed to the main control unit 14 to perform the above-described control operations of the main control unit 14 and to rearrange the data (DATA partition) stored in the magnetic tape 11. A relocation manager 15 is provided.
The rearrangement management unit 15 is provided with an index storage unit 16 that stores in advance data stored in the magnetic tape 11 (DATA partition) and index information of the index (INDEX partition) or stores it at startup. ing.

  The rearrangement management unit 15 determines whether each data on the magnetic tape 11 corresponding to the index information stored in the index storage unit 16 is valid data that meets a preset rearrangement determination criterion. A rearrangement determination unit 15A for determining whether or not each of the data determined to be rearrangeable by the rearrangement determination unit 15A is instructed to the main control unit 14 and the rearrangement of the respective data And a rearrangement execution command unit 15B for individually setting the position.

  For this reason, the data determined to be valid by the rearrangement determination unit 15A is efficiently transferred to a certain location (for example, the wrap 11c) on the magnetic tape 11 by the main control unit 14 operating in accordance with a command from the rearrangement execution command unit 15B. Part / see FIG. 6).

  Further, the above-described rearrangement management unit 15 instructs the main control unit 14 to read the index information on the magnetic tape 11 described above, and is read via the magnetic head 12 by the control operation of the main control unit 14. The index acquisition management unit 15C for storing the index information of the data on the magnetic tape 11 in the index storage unit 16 is provided in advance, and when data is rearranged, the index information of the data on the magnetic tape 11 is described later. Are collected in advance in real time.

Here, determination of valid data by the rearrangement determination unit 15A will be described.
First, the magnetic tape 11 described above is divided into three (three rows) wraps 11a, 11b, and 11c in the width direction (storage width region) of the magnetic tape 11 as shown in FIG. 7 in the first embodiment. Each lap constitutes one lap in which the recording areas along the forward path direction and the backward path direction are respectively half laps.
Each of the wraps 11a to 11c divided into three (three rows) is further divided into eight sectors (storage areas) each having a common rank in the first embodiment. The memory location can be quickly identified.

  The rearrangement determination unit 15A of the rearrangement management unit 15 described above includes a plurality of sections that are commonly divided into laps in the same direction (forward direction or return path) set in advance on the magnetic tape 11 that travels in the forward path direction or the backward path direction. Data stored in (in this embodiment, eight) sectors is targeted. Then, the following three points are provided in advance as rearrangement determination criteria for determining whether or not the rearrangement described above is possible for each data.

(1) The entire area including the forward path and the backward path has a vacant area wrap on the same magnetic tape.
(2) There is no valid file that straddles two or more sectors.
(3) A sector shifted by one in the half-wrap movement direction from the sector of the valid file is defined as a reallocation movement range (relocation destination sector), and a plurality of valid files are rearranged and moved between half-wraps in the same traveling direction. The ranges should not overlap. Note that the rearrangement movement range when the valid file is on the end side of the half wrap is the head sector of the reverse side half wrap.

  Then, the rearrangement determination unit 15A determines that the data matching these three points is valid data that can be rearranged. This makes it possible to relocate all of the relocation target data efficiently and quickly, which is also the content actually obtained as a result of the experiment.

  The rearrangement execution command unit 15B of the rearrangement management unit 15 described above is arranged in the forward direction or the backward direction when relocating a plurality of valid data determined by the rearrangement determination unit 15A and subjected to rearrangement. A read control operation for reading valid data stored in one target sector on the traveling magnetic tape 11, and the reading to the next sector in the same rank as the one read sector at the relocation destination position A rearrangement operation command function 15Ba is provided for instructing the main control unit 14 to perform a write control operation for writing a single valid data.

  As a result, the main control unit 14 can quickly transfer the magnetic head 12 to the rearrangement destination position (for example, the wrap 11c portion), for example, via the head drive mechanism 13 to be described later, and can rearrange (rewrite) data. It is made.

  Here, when the magnetic head 12 is moved beyond the wrap width region by the head drive mechanism 13 described above (moving in the width direction of the magnetic tape 11), a space necessary for movement between the sectors in advance (allowable space). ) Is set (not shown), and the magnetic head 12 can smoothly move without passing through the data storage area of each sector.

  Further, the main control unit 14 described above operates based on a command from the rearrangement execution command unit 15B, and performs a read control operation of valid data stored in one sector on the magnetic tape 11 and the read valid data. A data individual rearrangement control function 14 </ b> C that continuously executes the write control operation at the position of the data rearrangement destination is provided.

  As a result, the main control unit 14 freely moves the magnetic head 12 in the width direction of the magnetic tape 11 via the head drive mechanism 13 during the reciprocating reciprocation of the magnetic tape 11 in the forward and backward directions. The valid data stored in this sector can be freely transferred to the next rank sector of the relocation destination magnetic tape 11 within the shortest distance within the passage time of the allowable space corresponding to the movement time between laps as described above. It becomes possible to control the transfer, and thus the data rearrangement can be executed quickly and reliably.

  In addition, the rearrangement execution command unit 15B of the rearrangement management unit 15 writes the rearrangement data when the rearrangement of valid data stored in the magnetic tape 11 running in the forward direction and the backward direction is completed. An end position write command function 15Bc is provided that transmits an end position write command for writing a symbol indicating the data end position to the sector following the last sector to the main control unit 14 described above.

  Further, the rearrangement execution command unit 15B issues a start position write command for writing a symbol indicating the start position of the first valid data in the preceding stage of the first sector of the rearrangement lap when the rearrangement data is first written. A start position write command function 15Bb for transmitting to the main control unit 14 described above is provided.

  As a result, the installation area of the relocation destination position is clarified, the position of the available empty area on the magnetic tape 11 is clarified, and the subsequent writing process by the magnetic head 12 is executed quickly and efficiently. It becomes possible.

  In the first embodiment, the rearrangement execution command unit 15B of the rearrangement management unit 15 described above performs relocation on the unprocessed valid data remaining in the forward wrap of the magnetic tape 11 traveling in the backward direction. A back lead command function 15Bd for commanding the arrangement to the main control unit 14 is provided.

Correspondingly, the above-described main control unit 14 functions when a back read command is issued from the rearrangement execution command unit 15B, and is in an unprocessed state on the magnetic tape 11 traveling in the backward direction. The effective data of the forward-side sector is captured and controlled (back read) via the head drive mechanism 13 and the magnetic head 12, and the relocation destination corresponding to the effective data of the outward-side sector read by the magnetic head 12 As in the case of the above-mentioned rearrangement, an unprocessed data rearrangement control function 14E is sequentially written in the sector at the position.
Thereby, there is an advantage that unprocessed data that cannot be captured by reading in the forward direction can be effectively captured as described later.

  Next, the first embodiment described above will be described in more detail.

In FIG. 1, reference numeral 1 denotes a host device.
The host device 1 instructs the magnetic tape device 2 to start rearrangement, and may be either a management terminal for the magnetic tape 2 or a host computer that uses the magnetic tape device 2.

  As described above, the magnetic tape device 2 moves the operating position in the width direction of the magnetic tape 11 traveling in the forward direction or the backward direction, and data for each of the plurality of wraps 11a, 11b, or 11c on the magnetic tape 11 And a head drive mechanism 13 that guides the movement of the magnetic head 12 and transfers it to a desired position.

  The magnetic tape device 2 further includes a magnetic head transfer control function 14A for controlling the operation of the head drive mechanism 13 and a magnetic head read for executing the read or write operation by the magnetic head 12 based on an external command. A main control unit 14 having a / write control function 14B.

As described above, the main control unit 14 is provided with the rearrangement management unit 15 and the index storage unit 16, and the magnetic tape 11 is provided with the magnetic tape traveling drive mechanism 11 </ b> A.
Among these, the index storage unit 16 is a buffer for storing an index (INDEX) used in the rearrangement process.

  Here, the movement time between laps of the magnetic head 12 that reads and writes the magnetic tape 11 can be processed in a time that can be ignored with respect to the tape running speed. In this case, in consideration of the movement time between the wraps of the magnetic head 12, in the actual magnetic tape, as described above, a space corresponding to the movement time between the wraps is set between the sectors on the magnetic tape 11. (Not shown).

  The rearrangement management unit 15 reads the index recorded in the index storage unit 16 or the INDEX partition of the traveling magnetic tape 11 and determines whether or not to execute the rearrangement process, and the file recorded in the rearrangement destination A command to erase the wreckage of data, a command to write a valid file (valid data) to the relocation destination, and a command to move and write the recording information at the beginning and end positions of the DATA partition after copying all valid files And a rearrangement management unit having a function of instructing rearrangement processing by overwriting the index of the INDEX partition with the index after rearrangement.

  These command functions of the rearrangement management unit 15 are performed with respect to the main control unit 14 described above in the first embodiment, and the main control unit 14 receives each of these functions as described above. It is configured to execute a control operation. The rearrangement management unit 15 has a function of starting the rearrangement process upon receiving a rearrangement start instruction from the host device 1.

  Prior to the rearrangement operation, the rearrangement management unit 15 instructs the main control unit 14 to read out the index recorded in the INDEX partition of the magnetic tape 11 in advance, and this is used as the index. An index acquisition management unit 15 </ b> C that instructs the main control unit 14 to store in the storage unit 16 is provided. The reading and storing of the index information may be performed immediately after the start of the rearrangement operation, as will be described later.

  Here, the configuration of the DATA partition of the magnetic tape 11 used in this embodiment will be described with reference to FIG.

  The magnetic tape 11 shown in FIG. 7 includes wraps 11a, 11b, and 11c that indicate one reciprocal track for writing data at the same time, and a plurality of sectors that are partitioned at regular intervals to indicate physical positions in the longitudinal direction of the magnetic tape 11. The file write position on the magnetic tape 11 is specified by the wrap and the sector.

  As described above, the DATA partition of the magnetic tape 11 in the first embodiment is composed of the three wraps 11a, 11b, and 11c, and each wrap is divided into a half wrap in the forward direction and a half wrap in the return direction. . Each half lap in the forward direction and the backward direction is divided by eight sectors. In FIG. 7, the first sector to the eighth sector are described.

The start position of the DATA partition (hereinafter referred to as “BOP”) is at the start of the first wrap 11a, and the end of the DATA partition (hereinafter referred to as “EOP”) is set to the end of the third wrap 11c.
Each sector is sequentially assigned from the start end side of the magnetic tape 11 and starts from the first sector to the eighth sector. These are common addresses (ranks) for all half wraps.

Next, the start and end positions of the wrap will be described.
First, the start end of the forward direction side half wrap is on the tape start end side, and the end of the half wrap is on the tape end side. The starting end of the return direction side half wrap is on the end side of the tape, and the end of the half wrap is on the start end side of the tape.
That is, since this lap is composed of two half wraps, the starting end of the wrap is the starting end of the forward direction half wrap, and the end of the wrap is the end of the return direction half wrap.

  The file (data) recording starts from the BOP position. This recording operation is performed by the magnetic head 12 from the start end of the forward direction half wrap toward the end of the half wrap, and when reaching the end of the half wrap, the recording operation is continued to be switched to the return direction side half wrap. When the end of the side half lap is reached, the next lap is switched (for example, from the lap 11a to the lap 11b).

  In this way, the file (data) is recorded in the half wrap in the forward direction, the half wrap in the backward direction, and the half wrap in the forward direction of the next lap.

[Operation of First Embodiment]
Next, the operation of the data rearrangement process in the magnetic tape device 2 of the first embodiment will be described based on the flowcharts of FIGS.

First, the state of the DATA partition before relocation will be described with reference to FIG.
BOP is set at the top of the first lap 11a, and EOP is set at the end of the third lap 11c. As a result, files (data) are recorded in the DATA partition in the order of the first wrap, the second wrap, and the third wrap.

  From BOP to EOD (end position) is an area where a file (data) is written on the magnetic tape 11, and numerals 3001 to 3005 indicate valid files.

  As shown in FIG. 8, the valid files 3001 and 3002 are the forward laps of the first lap 11a, the file 3003 is the backward lap of the first lap 11a, and the file 3004 is the forward lap of the second lap 11b. 3005 is preliminarily arranged on the return lap side lap of the second lap 11b, and the valid file is distributed over a plurality of laps.

  Further, after the file 3005 (return direction of the second wrap 11b) is the end position (EOD) of the file on the magnetic tape 11, and after this EOD is a writable free area.

(Processing operations before and after relocation processing)
Next, the operation of rearranging each valid file from the state before the rearrangement shown in FIG. 8 will be described.

In FIG. 4, when the rearrangement instruction is received from the host device 1 and the rearrangement is activated, the rearrangement management unit 15 functions as a pre-equipped index acquisition management unit 15 </ b> C, and the index ( INDEX) reading instruction is sent, and when INDEX is read from the INDEX partition, it is stored in the index storage unit 16 (FIG. 4: Step S101 / INDEX reading and storing step).
Thereby, the main control unit 14 can always grasp the position of the file (data) to be rearranged by the index storage unit 16.

  The rearrangement management unit 15 functions as the above-described rearrangement determination unit 15A, and confirms the conditions of the above-described determination criteria (1) to (3) related to the valid file (valid data) from the obtained INDEX. It is determined whether or not valid data can be rearranged (FIG. 4: Step S102 / relocation possibility determination step).

This determination step is executed based on the flowchart disclosed in FIG. 5, and the conditions of the above-described determination criteria (1) to (3) are sequentially confirmed. This rearrangement availability determination step is executed by the rearrangement determination unit 15A of the rearrangement management unit 15.
Here, the relocation movement range when the valid file (valid data) is on the end side of the half wrap is the head sector of the reverse direction side half wrap.

  When it is determined that all of these conditions are satisfied (FIG. 4: Step S103 / Yes), the relocation management unit 15 recognizes that the INDEX data relating to the INDEX is relocatable and performs the relocation processing (FIG. 4). : Step S104 / relocation processing step). If the condition is not satisfied (FIG. 4: step S103 / No), the process is terminated without performing the rearrangement.

In the rearrangement process in step S104, the effective file is rearranged and the INDEX stored in the INDEX storage unit 16 is updated to the state after the rearrangement.
Thereafter, the INDEX partition is rewritten with the INDEX stored in the INDEX storage unit 12 (FIG. 4: Step S105 / INDEX rewriting process).

(Contents of reprocessing operation)
Next, the relocation processing (FIG. 4: step S104 / relocation processing step) executed in FIG. 4 will be described in detail with reference to the flowchart of FIG.
First, the main control unit 14 drives the magnetic head 12 with respect to the running magnetic tape 11, and erases the file debris remaining in the entire area of the lap (third lap 11c) determined as the rearrangement destination. (FIG. 6: Step S121 / unnecessary file erasing process). As a result, one reciprocation of the magnetic tape 11 is executed.

Next, the main control unit 14 starts moving in the outward direction of the first lap 11a.
First, the magnetic head 12 is moved to the forward halfway wrap of the first wrap of the file 3001 which is the valid file in the nearest sector among the valid files recorded in the forwardward half wrap, and the file 3001 is moved to. When it reaches, the data is read and the magnetic head 12 is moved to the forward wrap side half wrap of the third wrap 11c, and writing is performed at a position where the sector is shifted by one in the forward direction. At the same time, the information corresponding to the INDEX file 3001 in the INDEX storage unit 12 is updated to the post-arrangement state (FIG. 6: step S122 / relocation update processing step).

Here, if the valid file is a file before the end position of the half wrap, the movement is switched in the backward direction and then written to the relocation destination (FIG. 6: Step S123 / relocation destination writing process).
The operations in steps S122 and S123 are repeated until the end of the magnetic tape is reached (FIG. 6: step S124 / No). As a result, the data of the files 3002 and 3004 are written in the forward direction half wrap of the third wrap 11c.

  Thereafter, when the end of the tape is reached (FIG. 6: Step S125 / Yes), if the process is performed in the forward direction, the movement starts in the return direction (FIG. 6: Step S126 / return direction relocation switching). Process).

  If the process in the return direction is repeated until the end of the magnetic tape is reached as in the case of the forward direction described above (FIG. 6: step S124 / No), the return direction side is recorded as a half lap. The files 3005 and 3003 are written in the halfway wrap of the third wrap 11c.

When the rearrangement processing in the backward direction is completed (FIG. 6: Steps S124 and S125), the BOP write position is moved to the head of the third lap 11c to be rearranged, and the EOP write position is further moved to the end of the second wrap 11b. And recording (FIG. 6: Step S127), thereby completing the rearrangement processing operation of FIG.
This rearrangement processing operation is completed by one reciprocating operation.

  When the rearrangement is completed by the rearrangement management unit 15 in this way, the DATA partition becomes the state after the rearrangement of FIG.

  After the rearrangement, the BOP indicating the beginning of the DATA partition is set at the beginning of the third wrap 11c, and the EOP is set at the end of the second wrap 11b. As a result, the file (data) is recorded in the order of the third wrap 11c, the first wrap 11a, and the second wrap 11b. In the third wrap 11c, the valid files 3001 to 3005 are written, and the area other than the valid file is in an erased state with no unwritten files.

Further, the file 3003 is followed by EOD (the end of the file on the magnetic tape), and the first wrap 11a and the second wrap 11c, which are the areas after the EOD, become writable free areas.
In this way, the effective files are grouped into one wrap (third wrap 11c), and the other wraps can be set in a writable area.

  Here, when the back read control function 14D for reading the file written in the reverse side half wrap is additionally provided to the main control unit 14 described above, an operation command (back read command function 15Bd) for the control operation is provided. When the rearrangement execution command unit 15B of the rearrangement management unit 15 described above transmits, the back read control by the main control unit 14 is executed, and there is an effective file in which the rearrangement movement ranges overlap between the same direction half laps. Even if there are two valid files that overlap, and there is no valid file having the same rearrangement movement range in the half wrap in the reverse direction, it can be read back-read when moving in the reverse direction.

  For this reason, when the determination criterion (3) is not satisfied among the determination criteria (1) to (3) described above at the time of the above-described rearrangement determination, this determination criterion ( It becomes possible to relax the condition of 3).

That is, “the number of valid files with which the rearrangement movement range overlaps is two, and there is no valid file with the rearrangement movement range overlapping with the half wrap in the reverse direction.”
As a result, the relocation possible condition can be relaxed, and the target range of the original valid data that enables relocation can be expanded.

  In this case, on the magnetic tape 11 traveling in the return path direction, the main control unit 14 is based on the command from the rearrangement execution command unit 15B with respect to the unprocessed valid data remaining in the forward path wrap. The unprocessed data rearrangement control function 14E performs the capturing process via the head drive mechanism 13 and the magnetic head 12, and then performs the above-described rearrangement on the sector at the corresponding rearrangement destination position. Are processed so as to be written (unprocessed data rearrangement control step).

FIG. 10 shows a specific application example in this case.
When there is no back read function, relocation is impossible with the arrangement of valid data in FIG. On the other hand, rearrangement is possible when the back read function is provided, and the storage form of rearrangement executed in this case is as shown in FIG.

  Here, in the explanation of the operation of the magnetic tape device 2 in the above embodiment, the information processing steps to be specified are programmed and realized by a computer provided in the rearrangement management unit or the main control unit. You may comprise as follows.

In this case, the specified program may be recorded on a non-temporary recording medium such as a DVD, a CD, or a flash memory. In that case, the program is read from the recording medium by the computer and executed.
This is the same in other embodiments described below.

(Effect of 1st Embodiment)
As described above, in the first embodiment, the magnetic head (R / W header) 12 is moved from the first to the first without suspending the movement of the magnetic tape 11 in the same direction for the files dispersed in a plurality of wraps. By moving between the 3rd laps, the files are rearranged while switching the laps, so no matter how the files are distributed, including erasing the files of the relocation destination wrap, An excellent effect is obtained that data rearrangement can be executed in the time of the reciprocating operation.

[Second Embodiment]
Next, a second embodiment of the magnetic tape device according to the present invention will be described with reference to FIGS. Here, the same reference numerals are used for the same constituent members as those in the first embodiment described above.

〔Constitution〕
In the first embodiment described above, the files are rearranged only by moving the magnetic head (R / W header) 12 without stopping the running operation of the magnetic tape 11, so that there is a gap in the recording area between the files. In many cases it works, but there is room for improvement.

  In addition, if there is a valid file (valid data) that straddles two or more sectors, or if there are multiple valid files whose relocation movement range overlaps between half wraps, relocation cannot be performed, and this is the case. On the other hand, the criteria for determining whether or not relocation is possible for valid data is defined fairly strictly. For this reason, a restriction may be imposed on valid data to be rearranged.

In the second embodiment, the determination condition for whether or not to relocate the valid data is relaxed. At the same time, the configuration is such that after the files related to the valid data are collected in a separate buffer, A configuration is adopted in which these are written together in the relocation destination.
As a result, the files can be arranged without gaps, the conditions for performing the rearrangement can be relaxed, and the target range of the rearrangement can be expanded.

This will be specifically described below.
First, as shown in FIG. 11, the magnetic tape device according to the second embodiment differs from the magnetic tape device according to the first embodiment described above in that a file storage unit (data storage unit) that temporarily stores file information. ) 21 is additionally provided in the main control unit 24, and effective file rearrangement is executed via the file storage unit 21. Reference numeral 2B denotes the apparatus main body.

  Furthermore, in this FIG. 11, the code | symbol 24 shows the main control part in this 2nd Embodiment, and the code | symbol 25 shows a rearrangement management part similarly. The file storage unit 21 is a buffer having a capacity corresponding to one wrap for temporarily storing an effective file used in the rearrangement process in the rearrangement management unit 25.

  The rearrangement management unit 25 in the second embodiment has almost the same basic management function as that of the first embodiment described above. However, the main control unit 24 determines that the main control unit 24 is based on a command from the rearrangement management unit 25. It is characterized in that a significant change in function is set in the data read / write control contents for the magnetic head 12 at the time of data relocation to be executed.

  In other words, the main control unit 24 in the second embodiment, when storing the relocation effective data in the file storage unit 21, prioritizes the relocation operation in the first embodiment described above. The data storage priority processing function for controlling storage in the file storage unit (data storage unit) 21 and the writing of the stored relocation data to the relocation destination are taken out in ascending order of the preset file numbers. And a number-order rearrangement processing function for sequentially writing to the rearrangement destination.

On the other hand, in the second embodiment, the main control unit 24 deletes the data rearrangement destination remaining data in advance and the data individual rearrangement control function provided in the main control unit 14 of the first embodiment described above. No data erasure operation control function is provided.
For this reason, in this second embodiment, the number-order rearrangement processing function works effectively, and at the rearrangement destination, the storage state of the rearrangement data is set to a continuous state without a gap, thereby improving efficiency. There is an advantage that data rearrangement can be realized.

Here, the rearrangement determination unit 25A of the rearrangement management unit 25 described above includes, as the rearrangement determination criterion, a determination criterion that is greatly relaxed as compared to the rearrangement determination criterion in the first embodiment described above. Yes. That is,
(1) The entire area including the forward path and the backward path has a vacant area wrap on the same magnetic tape.
(2) It has at least two criteria for determining that no valid file exists in sectors of the same order on different half wraps in the same direction.

This is derived from the continuity of the relocation control with respect to the effective data of the main control unit 24 described above. The data read control and the write control to the relocation destination are divided into two control operations. This is because the data read control can be continuously performed without confirming the previous position.
Other configurations include the back read command function 15Bd transmitted from the rearrangement execution intention command unit 15B and the unprocessed data storage processing function 15E provided in the main control unit 24, and the case of the first embodiment described above. It is the same.

[Description of operation]
Next, the operation of a part or the whole of the apparatus centering on the rearrangement management unit 25 in the second embodiment will be described based on the flowcharts of FIGS. 14 to 15.
Here, as the state of the DATA partition on the magnetic tape 11 before the rearrangement, the state of FIG. 16A close to FIG. 8 in the case of the first embodiment is assumed.

  Further, in the second embodiment, the determination criterion (FIG. 4: step S102) and the rearrangement processing (FIG. 4: step S104) of the rearrangement performed in the flowchart of FIG. 5 in the first embodiment described above are as follows. This is different from the case of the first embodiment.

First, the criteria for determining whether or not rearrangement is possible (FIG. 4: corresponding to step S102) will be described.
In the second embodiment, the above-described two determination criteria (conditions) are set in advance from the index (INDEX) read from the INDEX partition.

  If all of these conditions are satisfied (FIG. 4: Step S103 / Yes), it is determined that rearrangement is possible, and the process proceeds to rearrangement processing (FIG. 4: step S104). If the condition is not satisfied (FIG. 4: Step S103 / No), the process is terminated without performing rearrangement (end).

  The other execution procedures (FIG. 4: steps S101 and S105) are the same as those in the first embodiment described above.

  Here, in the present embodiment, the relocation determination unit 25A sequentially determines whether or not the reexamination is possible for the valid data (valid file) based on the determination criteria (conditions) (1) and (2) in accordance with the flowchart shown in FIG. This is executed (FIG. 14: steps S311 to S314).

(Relocation processing)
Subsequently, the rearrangement processing (corresponding to step S104 in FIG. 4) of valid data (valid file) by the main control unit 24 in the second embodiment will be described based on the flowchart of FIG.

First, movement in the forward direction from the BOP is started (actually, the magnetic tape 11 travels toward the magnetic head 12 side).
The magnetic head 12 (R / W header) is moved to the forward halfway wrap of the first wrap of the valid file (file 3001) in the nearest sector among the valid files recorded in the forwardward half wrap. When the file 3001 is reached, it is read out and stored in the file storage unit (data storage unit) 21 (FIG. 15: steps S321 and S322).

  When storing the relocation effective data in the file storage unit 21, the main control unit 24 performs the storage control operation for the relocation effective data read by the magnetic head 12. It is executed in preference to the relocation operation provided (data storage priority processing step).

In this storage operation, when step S321 in FIG. 15 is repeated until the magnetic head 12 reaches the end of the magnetic tape 11 (FIG. 15: step S323 / No), the files 3002 and 3004 are stored in the file storage unit (data storage unit). 21 are sequentially stored.
Thereafter, when the end of the magnetic tape 11 is reached (FIG. 15: Step S323 / Yes), if the process is performed in the forward direction (FIG. 15: Step S324 / Yes), the movement starts in the return direction. (FIG. 15: Step S325).

  Then, the operations in steps S321 and S322 (return path processing) are repeated until the magnetic head 12 reaches the end of the magnetic tape 11 (FIG. 15: step S323 / No). As a result, the files 3005 and 3003 recorded in the half wrap are written in the file storage unit 21 by the rearrangement management unit 25 on the return path direction side.

  When the processing in the return direction is completed (FIG. 15: Step S323 / Yes, Step S324 / No), the rearrangement management unit 25 sequentially extracts from the younger number files in the file storage unit 21, and performs the rearrangement destination. Writing is started from the top of the third wrap, and the index in the index storage unit 16 corresponding to the written file is updated to the state after rearrangement (FIG. 15: step S326).

  That is, when the stored rearrangement data is rearranged, the main control unit 24 reads the file numbers assigned in advance to the stored valid data in ascending order and sequentially moves to the rearrangement destination position. It operates to write continuously (numbered rearrangement process step).

Subsequently, it is confirmed whether or not all the files stored in the file storage unit (data storage unit) 21 have been written (FIG. 15: step S327), and if there is a file that has not been written, the end of the magnetic tape 12 is checked. Is confirmed (FIG. 15: step S328).
If the terminal has not been reached, the process returns to step S326 described above. If the terminal has been reached, the traveling direction is switched to the return direction and the process returns to step S326 (FIG. 15: step S329).

If all the files (data) stored in the file storage unit (data storage unit) 21 have been written, finally, as shown in FIG. While moving to the top of the lap, the EOP is moved to the end of the second lap (FIG. 15: Step S330), thereby completing the rearrangement process (see FIG. 16B).
Here, the relocation execution process is executed and completed without a single reciprocating operation of the magnetic tape 11.

  When the rearrangement is completed by the rearrangement management unit 25 as described above, the DATA partition becomes the state after the rearrangement of FIG. 16B as described above.

  As is apparent from FIG. 16B, the valid files 3001 to 3005 are continuously written in the third wrap 11c without any gap, and the file 3005 is followed by EOD (the end of the file on the magnetic tape). After that, it becomes a writable free area, which is different from the case of the first embodiment (FIGS. 9 and 10B) described above.

  Here, if the back read control function for reading the file written in the reverse direction half wrap is added to the main control unit 24 described above, there is an effective file in which the rearrangement movement ranges overlap between the same direction half wraps. However, if there are two overlapping valid files and there is no valid file having the same rearrangement movement range in the reverse half wrap, it is possible to read back-read when moving in the reverse direction.

  That is, the above-described rearrangement execution command unit 15B instructs the main control unit 25 to rearrange the unprocessed valid data remaining on the forward-side wrap of the magnetic tape 11 traveling in the backward direction in advance. The case where the back read command function 15Bd is provided is set. At the same time, the main control unit 25 is provided with a back read control function 14D for reading out a file previously written in the reverse side half wrap through the magnetic head 12.

  Then, in the above-described priority processing step for storing valid data, the unprocessed valid data on the forward wrap on the magnetic tape 11 traveling in the backward direction is transferred from the relocation execution command unit 15B. The main control unit 25 performs capture control via the head drive mechanism 13 and the magnetic head 12 based on the command (outward path side residual data capture control step).

  Subsequently, the main control unit 25 sequentially stores the valid data on the outward path captured by the magnetic head 12 in the file storage unit 21 along the flow of data storage in the return path (unprocessed data storage processing step). ).

  For this reason, the back read control by the main control unit 24 is executed by the command from the rearrangement execution command unit 15B of the rearrangement management unit 25 described above, and there is an effective file in which the rearrangement movement ranges overlap between the same direction half laps. Even if there are two valid files that overlap, and there is no valid file with the same relocation movement range in the reverse half wrap, it can be read back-read when moving in the reverse direction. .

By realizing the back read control by the main control unit 24, the determination criterion (2) is satisfied among the relocation enablement conditions (relocation availability determination criteria) executed in steps S311 to S314 of FIG. In the case where the above condition is not satisfied, the following criterion (2) can be relaxed by providing the following criteria.
That is, “the number of valid files having the same sector is two, and there is no valid file having the same sector in the opposite half wrap.”

FIG. 17 shows a specific application example in this case.
When there is no back read function, relocation is impossible with the arrangement of the effective data in FIG. On the other hand, when the back read function is provided, rearrangement is possible even with the arrangement of the valid data in FIG. 17, and the storage form of the rearrangement executed in this case is as shown in FIG. become.
As a result, the relocation possible condition can be relaxed, and the target range of the original valid data that enables relocation can be expanded.

  Here, as in the case of the first embodiment described above, in the explanation of the operation of the magnetic tape device in the second embodiment, in each control step and processing step, the execution contents are programmed, You may make it implement | achieve in the computer with which the control part 24 or the rearrangement management part 25 is provided.

(Effect of 2nd Embodiment)
As described above, storing the files to be rearranged in the file storage unit 21 enables the files to be rearranged with no gap when written to the third wrap 11c as the rearrangement destination. The effect that a magnetic tape can be used efficiently is acquired.

  Further, by storing the file to be rearranged in the file storage unit 21, there is no need to repeat reading / writing during the tape movement operation, and even if there is an effective file that straddles two or more sectors, There is an effect that arrangement can be performed.

  Furthermore, when a back read control function for reading a file written in the reverse direction half wrap is added to the main control unit 24 described above, there is an effective file in which the rearrangement movement ranges overlap between the same direction half wraps. However, if there are two overlapping valid files and no valid file having the same rearrangement movement range exists in the reverse half wrap, it can be read back-read when moving in the reverse direction.

  For this reason, even when the determination criterion (2) described above is not satisfied, there is an advantage that the target range to be applied can be further expanded beyond the determination criterion (2) as described above.

Further, in the first embodiment described above, the relocation destination is formatted at the time of the relocation processing. However, in the second embodiment, the relocation destination formatting process is not necessary. The effect that it can shorten is acquired.
Other configurations and the operation and effects thereof are the same as in the case of the first embodiment described above.

  About each embodiment mentioned above, it is as follows when the new technical main point is put together. Note that the scope of the present invention is not necessarily limited to this.

[Appendix 1] (Relocation Management Department)
A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each of a plurality of laps set on the magnetic tape, and a movement operation of the magnetic head A magnetic tape device having an apparatus main body including a main control unit that controls the read or write operation by the magnetic head based on an external command while controlling via a head drive mechanism;
The apparatus main body is provided with a rearrangement management unit that commands the main control unit to perform each control operation of the main control unit and commands rearrangement of data stored in the magnetic tape,
In addition to the relocation management unit, an index storage unit that stores index information related to data stored in the magnetic tape is provided,
The relocation management unit
A rearrangement determination unit that determines whether or not each corresponding data is valid data that meets a preset rearrangement determination criterion based on the index information stored in the index storage unit; and the rearrangement determination A relocation execution command unit for instructing the main control unit to relocate the data determined to be relocatable by the unit and setting a relocation destination position of the data. A magnetic tape device characterized by that.

[Appendix 2] (Criteria for rearrangement)
In the magnetic tape device according to appendix 1,
The relocation determination unit targets data stored in a plurality of sectors divided in common for each lap set in advance on a magnetic tape that travels in the forward direction or the backward direction. As a rearrangement determination criterion for determining whether or not the rearrangement is possible,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) There is no valid file that straddles two or more sectors.
(3) A sector shifted by one in the half-wrap movement direction from the sector of the valid file is set as the reallocation movement range, and the reallocation movement ranges of multiple valid files between half-wraps in the same direction do not overlap. The relocation movement range when the valid file is at the end of the half wrap is the first sector of the reverse half wrap.
A magnetic tape device characterized in that at least three criteria are determined, and data conforming to the criteria is determined as valid data that can be rearranged.

[Appendix 3] (Relocation destination / allocation to the next sector)
In the magnetic tape device according to appendix 1,
The rearrangement execution command unit, when rearranging each of a plurality of data determined by the rearrangement determination unit and subject to rearrangement, sets the target sector on the magnetic tape traveling in the forward direction or the backward direction. A read control operation for sequentially reading the stored valid data and a write control operation for writing the one valid data read to the sector next to the sector of the same rank at the relocation destination position, respectively, to the main control unit A magnetic tape device having a rearrangement operation command function for commanding.

[Appendix 4] (Relocation / Reading and writing one by one)
In the magnetic tape device according to attachment 3,
The main control unit operates based on a command from the relocation execution command unit, and performs a read control operation of valid data stored in one sector on the magnetic tape and the relocation destination of the read valid data A magnetic tape apparatus comprising a data individual rearrangement control function for continuously executing the write control operation at the position of.

[Appendix 5] (Data start / end position writing)
In the magnetic tape device according to attachment 3,
The rearrangement execution command unit, when the rearrangement of valid data stored on the magnetic tape traveling in the forward direction and the backward direction is completed, stores data in the sector next to the last sector to which the rearrangement data has been written. An end position write command function for writing a symbol indicating the end position, and a start of writing a symbol indicating the start position of the first valid data to the preceding stage of the first sector of the relocation wrap when the relocation data is written for the first time A magnetic tape device having a position writing command function.

[Appendix 6] (Back lead command function)
In the magnetic tape device according to attachment 3,
The rearrangement execution command unit has a back lead command function for commanding the main control unit to rearrange the unprocessed valid data remaining in the forward path wrap of the magnetic tape traveling in the backward direction,
The main control unit is
It functions when a back read command is issued from the rearrangement execution command unit, and the valid data of the forward sector in the unprocessed state on the magnetic tape running in the backward direction is passed through the head drive mechanism and the magnetic head. And an unprocessed data rearrangement control function for sequentially writing valid data of the forward sector read by the magnetic head to the next sector of the same rank sector at the corresponding rearrangement position. A magnetic tape device characterized by comprising.

[Appendix 7] (Second Embodiment)
In the magnetic tape device according to appendix 1,
The main control unit is provided with a file storage unit for storing the effective data for rearrangement read by the magnetic head, and
The main control unit has a data storage priority processing function for preferentially storing the relocation operation when storing the relocation effective data in the file storage unit, and relocating the stored relocation data. Is provided with a number-order rearrangement processing function that takes out the preset file numbers in ascending order and sequentially writes them in the rearrangement destination sequentially.

[Appendix 8] (Second Embodiment)
In the magnetic tape device according to appendix 7,
The relocation determination unit targets data stored in a plurality of sectors divided in common for each lap set in advance on a magnetic tape that travels in the forward direction or the backward direction. As a rearrangement determination criterion for determining whether or not the rearrangement is possible,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) There is no valid file in the same-order sector on the same half-wrap and another different half-wrap,
A magnetic tape device characterized in that at least two criteria of the above are satisfied, and data conforming to these criteria is regarded as valid data that can be rearranged.

[Supplementary Note 9] (Second Embodiment / Back Lead Command Function)
In the magnetic tape device according to appendix 7,
The rearrangement execution command unit has a back lead command function for commanding the main control unit to rearrange the unprocessed valid data remaining in at least the outward wrap of the magnetic tape traveling in the backward direction,
The main control unit functions when a back-read command is issued from the rearrangement execution command unit, and stores the effective data on the forward wrap that is in an unprocessed state on the magnetic tape traveling in the return path direction. Unprocessed data that is captured and controlled via the drive mechanism and the magnetic head, and that the effective data on the forward wrap read by the magnetic head is sequentially stored in the file storage unit along the flow of effective data storage in the backward direction A magnetic tape device having a storage processing function.

[Supplementary Note 10] (Invention of Method / Corresponding to Supplementary Note 1)
A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each of a plurality of laps set on the magnetic tape, and a movement operation of the magnetic head A magnetic tape device including a main control unit that controls the read or write operation by the magnetic head based on an external command while controlling via a head drive mechanism, and the main control unit is separately provided in advance. In a data rearrangement method that operates according to a command from the rearrangement management unit and executes rearrangement of data stored in the magnetic tape,
The rearrangement management unit reads the attribute and arrangement position of each data recorded on the magnetic tape by reading from an index storage unit equipped in advance with an index of each data concerning a plurality of files recorded on the magnetic tape. Check each file (data file confirmation process)
The relocation determination unit of the relocation management unit determines whether each corresponding data based on the index information stored in the index storage unit is valid data that conforms to a preset relocation availability determination criterion. Judgment (relocation possibility judgment process),
For each effective data determined to be relocatable by the relocation determination unit, the relocation execution command unit instructs the relocation to the main control unit, and the position of the relocation destination of the data is determined. A data rearrangement method characterized by being individually set (relocation execution command process).

[Appendix 11] (Appendix 2 correspondence / relocation criteria)
In the data rearrangement method according to attachment 10,
When determining whether or not relocation can be performed by the relocation determination unit, data stored in a plurality of sectors that are partitioned in common for each lap in the same direction set in advance on a magnetic tape traveling in the forward direction or the backward direction As well as
As a rearrangement determination criterion for determining whether or not the rearrangement is possible for each data,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) There is no valid file that straddles two or more sectors.
(3) A sector shifted by one in the half-wrap movement direction from the sector of the valid file is set as the reallocation movement range, and the reallocation movement ranges of multiple valid files between half-wraps in the same direction do not overlap. The relocation movement range when the valid file is at the end of the half wrap is the first sector of the reverse half wrap.
Pre-install at least three criteria
A data rearrangement method characterized in that the data that meets the rearrangement determination criterion is determined as valid data that can be rearranged by the rearrangement determination unit.

[Appendix 12] (Appendix 3 supported / relocated to the next sector in the same order)
In the data rearrangement method according to attachment 10,
When executing the relocation of each of the multiple data subject to relocation,
A data read control operation for reading data stored in one sector that has been subject to rearrangement on the magnetic tape traveling in the forward direction or the backward direction via the magnetic head is performed by the rearrangement execution command unit. The main control unit executes based on the command,
Subsequently, the main control unit executes a write control operation in which the magnetic head is transferred to the sector next to the sector at the rearrangement position at the same rank position as the one sector and the read data is written. A data rearrangement method characterized by that.

[Appendix 13] (Appendix 4 supported / rearranged one by one)
In the data rearrangement method described in appendix 12,
A read control operation for data stored in one sector on the magnetic tape and a write control operation for the read data at the relocation destination position are based on a command from the relocation execution command unit. A data rearrangement method characterized in that the main control unit continuously executes each data.

[Appendix 14] (Appendix 5 / Data start / end position writing)
In the data rearrangement method described in appendix 12,
After the rearrangement of the data stored on the magnetic tape running in the forward direction and the backward direction is completed, a symbol indicating the data end position is added to the sector next to the last sector in which the rearranged data is written. The main control unit performs write control via the magnetic head based on a command from the placement execution command unit,
When the relocation data is written for the first time, the main control unit controls the writing of a symbol indicating the start position of the first data before the first sector of the relocation wrap through the magnetic head. A data rearrangement method characterized by that.

[Appendix 15] (Appendix 6 supported / back lead command function)
In the data rearrangement method described in appendix 12,
The rearrangement execution command unit has a back lead command function for instructing the main control unit to rearrange the unprocessed valid data remaining in the forward path wrap of the magnetic tape traveling in the backward direction in advance.
For the unprocessed valid data remaining in the forward path wrap on the magnetic tape traveling in the return path direction, the main control unit performs the head drive mechanism and the head drive mechanism based on the command from the rearrangement execution command unit. Capture control through the magnetic head,
Subsequently, the data rearrangement method is characterized in that the data is sequentially written in the sector next to the sector in the same order of the corresponding rearrangement destination (unprocessed data rearrangement control step).

[Supplementary Note 16] (Appendix 7 Correspondence / Second Embodiment)
In the data rearrangement method according to attachment 10,
The main control unit is preliminarily provided with a file storage unit for storing effective data for rearrangement read by the magnetic head,
When storing the effective data for rearrangement in the file storage unit, the main control unit executes the storage operation of the effective data for rearrangement read by the magnetic head in preference to the rearrangement operation ( Data storage priority processing step),
When the stored rearrangement data is rearranged, the main control unit reads out the file numbers assigned to the stored valid data in ascending order and sequentially writes them at the rearrangement destination positions. A data rearrangement method characterized by the fact that it is configured (numbered rearrangement processing step).

[Supplementary Note 17] (Appendix 8 Correspondence / Second Embodiment)
In the data relocation method described in appendix 16,
In the relocation possibility determination step, the data stored in a plurality of sectors divided in common for each lap set in advance on the magnetic tape traveling in the forward direction or the backward direction is targeted. ,
As a rearrangement determination criterion for determining whether or not the rearrangement is possible for each data,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) has at least two criteria that no valid file exists in a sector in the same order on other half wraps in the same direction,
A data rearrangement method characterized in that the data that meets the rearrangement determination criterion is determined as valid data that can be rearranged by the rearrangement determination unit.

[Supplementary Note 18] (Appendix 9 Correspondence / Second Embodiment / Back Lead Command Function)
In the data relocation method described in appendix 16,
The rearrangement execution command unit has a back lead command function for instructing the main control unit to rearrange the unprocessed valid data remaining on the forward wrap of the magnetic tape traveling in the backward direction in advance. ,
In the priority processing step of the effective data storage,
Based on a command from the rearrangement execution command unit, the main control unit sends valid data in an unprocessed state on the forward wrap on the magnetic tape traveling in the backward direction via the head drive mechanism and the magnetic head. Capture control (outgoing side residual data capture control process),
Subsequently, the main control unit sequentially stores the effective data on the outward path captured by the magnetic head in the file storage unit in accordance with the data storage flow in the return direction (unprocessed data storage process). A data rearrangement method characterized by a process).

[Appendix 19] (Program invention / Appendix 10)
A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each of a plurality of laps set on the magnetic tape, and a movement operation of the magnetic head A magnetic tape device having a device main body with a main control unit that controls the read or write operation by the magnetic head based on an external command while controlling via a head drive mechanism,
The apparatus main body is preinstalled with a rearrangement management unit that commands the main control unit to perform each control operation of the main control unit and commands rearrangement of data stored on the magnetic tape. And
The index of each data concerning a plurality of files recorded on the magnetic tape is read from an index storage unit separately equipped in advance, and the attribute and arrangement position of each data recorded on the magnetic tape are confirmed for each file. Index confirmation processing function,
A relocation availability determination processing function for determining whether each of the corresponding data based on each index information stored in the index storage unit meets a preset relocation availability determination criterion;
In addition, for each data determined to be relocatable by the relocation determination processing function, a relocation is instructed to the main control unit and a relocation destination position of each data is individually set. Placement execution command function,
And a data rearrangement operation control program characterized in that the computer is provided in the rearrangement management unit.

[Appendix 20] (Appendix 11 correspondence / relocation criteria)
In the operation control program for data rearrangement described in appendix 19,
In the relocation availability determination processing function,
While targeting data stored in any of a plurality of sectors that are partitioned in common for each lap set in advance on the magnetic tape traveling in the forward direction and the backward direction,
As a rearrangement determination criterion for determining whether or not the rearrangement is possible for each data,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) There is no valid file that straddles two or more sectors.
(3) A sector shifted by one in the half-wrap movement direction from the sector of the effective file is defined as a relocation movement range, and at least the relocation movement ranges of a plurality of valid files between half wraps in the same direction do not overlap. Have three as criteria,
The data that conforms to this rearrangement determination criterion is to determine that the rearrangement availability determination processing function is valid data that can be rearranged,
An operation control program for data rearrangement characterized by causing the computer to realize this.

[Appendix 21] (Appendix 12 / Relocation to the next sector in the same order as the original sector)
In the operation control program for data rearrangement described in appendix 19,
In the relocation execution command function,
Commands the main control unit to read out data stored in one sector in the same direction that has been relocated on the magnetic tape traveling in the forward or backward direction via the magnetic head Read operation command function
The main control unit performs a data write operation for writing the read data to the next sector of the rearranged sector in the same rank as the one sector by controlling the transfer of the head drive mechanism and the magnetic head. Has a write operation command function to command
An operation control program for data rearrangement characterized in that each of these command functions is realized by the computer.

[Appendix 22] (Appendix 13 / Relocation one by one)
In the data rearrangement operation control program according to attachment 21,
The main control unit continuously executes a read control operation for data stored in one sector on the magnetic tape and a write control operation for the read data at the relocation destination position. Provide a relocation individual execution command function to command,
An operation control program for data rearrangement characterized by causing the computer to realize this.

[Appendix 23] (Appendix 14 correspondence / data start / end position writing)
In the data rearrangement operation control program according to attachment 21,
After the rearrangement of the data stored in the magnetic tape traveling in the forward direction and the backward direction is completed, a symbol indicating the data end position is indicated in the sector next to the last sector in which the rearranged data is written. End position writing command transmission function to command the main control unit to control writing via
In the first writing of the rearrangement data, the main control is performed so that the symbol indicating the start position of the first data is controlled to be written to the first stage of the first sector of the rearrangement wrap through the magnetic head. Start position writing command transmission function to command
And an operation control program for data rearrangement characterized by causing the computer to realize them.

[Appendix 24] (Appendix 15 Correspondence: Back Lead Command Function)
In the data rearrangement operation control program according to attachment 21,
The rearrangement execution command function includes a back lead command function for instructing the main control unit to rearrange the unprocessed valid data remaining in the forward path wrap of the magnetic tape traveling in the backward direction in advance. ,
The relocation execution command function includes, as its contents:
Effective data capture that instructs the main control unit to capture, via the head drive mechanism and the magnetic head, unprocessed valid data remaining on the forward wrap at least on the magnetic tape traveling in the backward direction Command function,
And an effective data write command function for instructing the main control unit to write the captured effective data to the sector at the corresponding relocation destination position in the same manner as in the relocation,
A data rearrangement operation control program characterized in that the program is realized by the computer.

[Supplementary Note 25] (Corresponding to Supplementary Note 16 / Second Embodiment)
In the operation control program for data rearrangement described in appendix 19,
The main control unit is preliminarily provided with a file storage unit for storing effective data for rearrangement read by the magnetic head,
When storing the relocation effective data in the file storage unit, the main control unit is configured to execute the storage operation of the relocation effective data read by the magnetic head in preference to the relocation operation. Data storage priority processing function to command,
In the rearrangement of the stored rearrangement data, the main data is read out in ascending order of the file numbers attached to the stored valid data and sequentially written in the rearrangement destination positions. Rearrangement continuous processing function commanded to the control unit,
And a data rearrangement operation control program characterized in that each of the processing functions is realized by the computer.

[Supplementary Note 26] (Appendix 17 Compatible / Second Embodiment)
In the data rearrangement operation control program according to attachment 25,
In the relocation availability determination processing function,
While targeting data stored in a plurality of sectors that are partitioned in common for each lap set in advance on the magnetic tape traveling in the forward or backward direction,
As a rearrangement determination criterion for determining whether or not the rearrangement is possible for each data,
(1) The entire area including the forward path and the return path has a vacant wrap on the same magnetic tape.
(2) It is provided in advance with at least two points that there is no valid file in the same rank sector on the other half wrap on the same direction half wrap,
The data that conforms to this rearrangement determination criterion is to determine that the rearrangement availability determination processing function is valid data that can be rearranged,
An operation control program for data rearrangement characterized by causing the computer to realize this determination function.

[Supplementary Note 27] (Appendix 18 Compatible / Second Embodiment / Back Lead Command Function)
In the data rearrangement operation control program according to attachment 25,
The rearrangement execution command function includes a back lead command function for instructing the main control unit to rearrange the unprocessed valid data remaining on the forward wrap of the magnetic tape traveling in the backward direction in advance. And
In the data storage priority processing function,
Outward-side remaining data capture command for instructing the main control unit to capture valid data in the unprocessed state on the forward-side wrap on the magnetic tape traveling in the backward direction via the head drive mechanism and the magnetic head A function and an unprocessed data storage processing function for instructing the main control unit to sequentially store the effective data on the outward path captured by the magnetic head in the file storage unit along the data storage flow in the return path direction. Including
An operation control program for data rearrangement characterized by causing the computer to realize this.

  The present invention is applicable to all storage media whose data storage areas are specified by wraps and sectors.

DESCRIPTION OF SYMBOLS 1 High-order apparatus 2 Magnetic tape apparatus 2A, 2B Apparatus main body 11 Magnetic tape 11A Magnetic tape travel drive apparatus 11a 1st wrap 11b 2nd wrap 11c 3rd wrap 12 Magnetic head 13 Head drive mechanism 14,24 Main control part 14A For magnetic heads Transfer control function 14B Magnetic head read / write control function 14C Individual data relocation control function 14D Back read control function 14E Unprocessed data relocation control function 15, 25 Relocation management unit 15A, 25A Relocation determination unit 15B Relocation execution command Unit 15Ba Relocation operation example function 15Bb Start position write command function 15Bc End position write command function 15Bd Back read command function 15C Index acquisition management unit 16 Index storage unit 21 File storage unit (data storage unit)
24C Data storage priority processing function 24D Number order rearrangement processing function

Claims (10)

A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each of a plurality of laps set on the magnetic tape, and a movement operation of the magnetic head A magnetic tape device having an apparatus main body including a main control unit that controls the read or write operation by the magnetic head based on an external command while controlling via a head drive mechanism;
The apparatus main body is provided with a rearrangement management unit that commands the main control unit to perform each control operation of the main control unit and commands rearrangement of data stored in the magnetic tape,
In addition to the relocation management unit, an index storage unit that stores index information related to data stored in the magnetic tape is provided,
The relocation management unit
A rearrangement determination unit that determines whether or not each corresponding data is valid data that meets a preset rearrangement determination criterion based on the index information stored in the index storage unit; and the rearrangement determination A relocation execution command unit for instructing the main control unit to relocate the data determined to be relocatable by the unit and setting a relocation destination position of the data. A magnetic tape device characterized by that. The magnetic tape device according to claim 1,
The relocation determination unit targets data stored in a plurality of sectors divided in common for each lap set in advance on a magnetic tape that travels in the forward direction or the backward direction. As a rearrangement determination criterion for determining whether or not the rearrangement is possible,
(1) The entire magnetic field including the forward path and the return path has a vacant area wrap on the same magnetic tape.
(2) There is no valid file that straddles two or more sectors.
(3) A sector shifted by one in the half-wrap movement direction from the sector of the valid file is set as the reallocation movement range, and the reallocation movement ranges of a plurality of valid files between the half-wraps in the same direction are not overlapped (here The relocation movement range when the valid file is at the end of the half wrap is the first sector of the reverse half wrap)
A magnetic tape device characterized in that at least three criteria are determined, and data conforming to the criteria is determined as valid data that can be rearranged. The magnetic tape device according to claim 1,
The rearrangement execution command unit, when rearranging each of a plurality of data determined by the rearrangement determination unit and subject to rearrangement, sets the target sector on the magnetic tape traveling in the forward direction or the backward direction. A read control operation for sequentially reading the stored valid data and a write control operation for writing the one valid data read to the sector next to the sector of the same rank at the relocation destination position, respectively, to the main control unit A magnetic tape device having a rearrangement operation command function for commanding. The magnetic tape device according to claim 3, wherein
The main control unit operates based on a command from the relocation execution command unit, and performs a read control operation of valid data stored in one sector on the magnetic tape and the relocation destination of the read valid data A magnetic tape apparatus comprising a data individual rearrangement control function for continuously executing the write control operation at the position of. The magnetic tape device according to claim 3, wherein
The rearrangement execution command unit has a back lead command function for commanding the main control unit to rearrange the unprocessed valid data remaining in the forward path wrap of the magnetic tape traveling in the backward direction,
The main control unit is
It functions when a back read command is issued from the rearrangement execution command unit, and the valid data of the forward sector in the unprocessed state on the magnetic tape running in the backward direction is passed through the head drive mechanism and the magnetic head. And an unprocessed data rearrangement control function for sequentially writing valid data of the forward sector read by the magnetic head to the next sector of the same rank sector at the corresponding rearrangement position. A magnetic tape device characterized by comprising. The magnetic tape device according to claim 1,
The main control unit is provided with a file storage unit for storing the effective data for rearrangement read by the magnetic head, and
The main control unit has a data storage priority processing function for preferentially storing the relocation operation when storing the relocation effective data in the file storage unit, and relocating the stored relocation data. Is provided with a number-order rearrangement processing function that takes out the preset file numbers in ascending order and sequentially writes them in the rearrangement destination sequentially. A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each lap on the magnetic tape, and the movement operation of the magnetic head via the head drive mechanism A magnetic tape device including a main control unit that controls and controls the read or write operation by the magnetic head based on an external command, from a relocation management unit that is separately equipped with the main control unit in advance. In a data rearrangement method that operates according to a command and executes rearrangement of data stored in the magnetic tape,
The rearrangement management unit reads the attribute and arrangement position of each data recorded on the magnetic tape by reading from an index storage unit equipped in advance with an index of each data concerning a plurality of files recorded on the magnetic tape. Check for each file,
The relocation determination unit of the relocation management unit determines whether each corresponding data based on the index information stored in the index storage unit is valid data that conforms to a preset relocation availability determination criterion. Judgment,
For each effective data determined to be relocatable by the relocation determination unit, the relocation execution command unit instructs the relocation to the main control unit, and the position of the relocation destination of the data is determined. Data relocation method characterized by setting individually. The data rearrangement method according to claim 7,
The main control unit is preliminarily provided with a file storage unit for storing effective data for rearrangement read by the magnetic head,
In storing the relocation effective data in the file storage unit, the main control unit executes the storage operation of the relocation effective data read by the magnetic head in preference to the relocation operation,
When the stored rearrangement data is rearranged, the main control unit reads out the file numbers assigned to the stored valid data in ascending order and sequentially writes them at the rearrangement destination positions. A data rearrangement method characterized by that. A magnetic head that moves in the width direction of the magnetic tape traveling in the forward direction or the backward direction and executes reading or writing of data for each of a plurality of laps set on the magnetic tape, and a movement operation of the magnetic head A magnetic tape device having a device main body with a main control unit that controls the read or write operation by the magnetic head based on an external command while controlling via a head drive mechanism,
The apparatus main body is preinstalled with a rearrangement management unit that commands the main control unit to perform each control operation of the main control unit and commands rearrangement of data stored on the magnetic tape. And
The index of each data concerning a plurality of files recorded on the magnetic tape is read from an index storage unit separately equipped in advance, and the attribute and arrangement position of each data recorded on the magnetic tape are confirmed for each file. Index confirmation processing function,
A relocation availability determination processing function for determining whether each of the corresponding data based on each index information stored in the index storage unit meets a preset relocation availability determination criterion;
In addition, for each data determined to be relocatable by the relocation determination processing function, a relocation is instructed to the main control unit and a relocation destination position of each data is individually set. Placement execution command function,
And a data rearrangement operation control program characterized in that the computer is provided in the rearrangement management unit. In the data rearrangement operation control program according to claim 9,
The main control unit is preliminarily provided with a file storage unit for storing effective data for rearrangement read by the magnetic head,
When storing the relocation effective data in the file storage unit, the main control unit is configured to execute the storage operation of the relocation effective data read by the magnetic head in preference to the relocation operation. Data storage priority processing function to command,
In the rearrangement of the stored rearrangement data, the main data is read out in ascending order of the file numbers attached to the stored valid data and sequentially written in the rearrangement destination positions. Rearrangement continuous processing function commanded to the control unit,
And a data rearrangement operation control program characterized in that each of the processing functions is realized by the computer.

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