JP2817499B2 - Library type cartridge type magnetic tape unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a library-type cartridge-type magnetic tape apparatus for writing and reading data by moving the magnetic tape to a tape drive mechanism by an accessor from a storage unit in which a number of cartridge-type magnetic tapes are stored. About.

[0002]

2. Description of the Related Art Conventionally, in a library type cartridge type magnetic tape device of this kind, a storage position of a cartridge type magnetic tape once set is taken over unless an artificial setting is changed, and data is read or written. Reciprocation to the tape drive mechanism is always performed based on the same storage position.

[0003]

In the above-described conventional library-type cartridge-type magnetic tape device, the accessor for moving the cartridge-type magnetic tape takes out the cartridge-type magnetic tape from the storage section, moves to the tape drive mechanism, and stores data. When returning from the tape drive mechanism to the storage section after the end of reading or writing, the take-out position and return position of the cartridge type magnetic tape are always the same, so the frequently accessed cartridge type magnetic tape is far from the tape drive mechanism. However, there is a disadvantage that the overall access time becomes longer, and manual operation is required to move the frequently accessed cartridge type magnetic tape closer to the tape drive mechanism in order to shorten the access time. The disadvantage is that the operator is burdened. .

SUMMARY OF THE INVENTION An object of the present invention is to provide a library-type cartridge-type magnetic tape apparatus which has a short overall access time without the burden of an operator who manually moves a frequently accessed cartridge-type magnetic tape to a position close to a tape drive mechanism. To provide.

[0005]

In the library type cartridge type magnetic tape device of the present invention, the storage portion is divided into a first area located near the tape drive mechanism and a second area far from the tape drive mechanism. , Storage unit,
After storing the number of accesses of the cartridge type magnetic tape stored at the position for each storage position of each area of the storage unit in the storage unit, refer to the access number information stored in the storage unit. A is the smallest number of accesses of the cartridge type magnetic tape stored in the first area, and b is the largest number of accesses of the cartridge type magnetic tape stored in the second area. And a and b
When a <b, the cartridge type magnetic tape stored in the storage position having the value of b is moved into the first area by the accessor, and the magnetic tape is stored in the storage position having the value of a. And a control unit for moving the cartridge type magnetic tape in the second area by the accessor and updating the access count information in the storage unit in accordance with the movement of the magnetic tape.

[0006]

The largest number of accesses a of the cartridge magnetic tapes stored in the second area and the smallest number of accesses b of the cartridge magnetic tapes stored in the first area. When a <b, the magnetic tape corresponding to the value of b is moved into the first area, and the magnetic tape corresponding to the value of a is moved into the second area. As a result of the relatively frequent magnetic tape being stored in the first area, the overall access time is reduced.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of a library type cartridge type magnetic tape apparatus according to the present invention, and FIG.
5 is a flowchart of the process of the control unit 9 of FIG.

The library type cartridge type magnetic tape device 1 comprises an accessor 2, a housing 3, and a tape drive mechanism 8
, A control unit 9 and a storage unit 10.

The accessor 2 moves a cartridge type magnetic tape. The storage section 3 stores a large number of cartridge type magnetic tapes and is divided into areas 4 and 5. Area 4
Is an area for accommodating a cartridge type magnetic tape having a relatively high access frequency, which is located near the tape drive mechanism 8. The area 5 is an area for accommodating a cartridge type magnetic tape having a relatively low access frequency, and is located farther from the tape drive mechanism 8 than the area 4 is.
Here, each of the areas 4 and 5 comprises a large number of slots 6, and each slot 6 can accommodate one cartridge type magnetic tape. The area 4 always has a certain number of empty slots 7. The tape drive mechanism 8 writes and reads data to and from a cartridge type magnetic tape. The storage unit 10 stores the areas 4 and 5 of the storage unit 3.
This is a memory for storing the position of each slot 6 and the number of times of access to the cartridge type magnetic tape stored in that position. The control unit 9 controls the areas 4 and 5 in the storage unit 3.
The number of accesses to the cartridge type magnetic tape stored for each position of each slot 6 is stored in the storage unit 10, and referring to the number of accesses information stored in the storage unit 10 as shown in FIG. And each slot 6 in area 4
Among the slots 6 in the area 5 are set to b (step 12), and the number of accesses having the lowest access frequency is set to b (step 12). b (step 13),
If b is larger than a, the cartridge type magnetic tape stored in the slot of the area 5 having the value of b is moved to the empty slot 7 in the area 4 using the accessor 2 (step 14). The control unit 9 further moves the cartridge type magnetic tape stored in the slot of the area 4 having the value of a to the empty slot 7 in the area 5 by using the accessor 2 (step 15).
The number of accesses corresponding to the movement position of the cartridge type magnetic tape within 0 is updated (step 16), and the same processing as above is performed again. This process is repeated until the value of a is greater than or equal to b.

In the library type cartridge type magnetic tape device of this embodiment, the maximum number of accesses b in the area 5
And the minimum number of accesses a in the area 4, b>
At the time of a, the magnetic tape corresponding to b is moved to the area 4 and the magnetic tape corresponding to a is moved to the area 5.
As a result of the magnetic tapes that are accessed relatively frequently gathering in an area near the tape drive mechanism 8, the overall access time is reduced without requiring any human intervention.

[0012]

As described above, according to the present invention, the number of accesses in the first and second areas is compared, and a cartridge-type magnetic tape having a high access frequency is placed near the tape drive mechanism without operator's work. By moving
There is an effect that the overall access time of the cartridge type magnetic tape can be shortened without imposing a burden on the operator.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of a library type cartridge type magnetic tape device of the present invention.

FIG. 2 is a flowchart of a process of a control unit 9 in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Library type cartridge type magnetic tape device 2 Accessor 3 Storage part 4,5 Area 6 Slot 7 Empty slot 8 Tape drive mechanism 9 Control part 10 Storage part 11,12, ..., 16 steps

Claims (1)

(57) [Claims] 1. A library-type cartridge-type magnetic tape device that writes and reads data by moving said magnetic tape to a tape drive mechanism by an accessor from a storage unit in which a large number of cartridge-type magnetic tapes are stored. Is divided into a first area located near the tape drive mechanism and a second area far from the tape drive mechanism, and is stored at each of the storage positions of the storage unit and each area of the storage unit. After storing the number of accesses of the cartridge type magnetic tape in the storage area, referring to the access number information stored in the storage section, the number of accesses of the cartridge type magnetic tape stored in the first area is referred to. A is the smallest number of accesses, and the cartridge stored in the second area is When the largest number of accesses of the cartridge type magnetic tape is b, a and b
When a <b, the cartridge type magnetic tape stored in the storage position having the value of b is moved into the first area by the accessor, and the magnetic tape is stored in the storage position having the value of a. A library type cartridge having a cartridge type magnetic tape which is moved by an accessor into a second area, and updating the access count information in the storage unit in accordance with the movement of the magnetic tape. Type magnetic tape device.