JPS61163429A - Replaceable recording medium management system - Google Patents

Abstract

PURPOSE:To reduce the overhead of a secondary storage device routine in an operating system of a host and to attain ease of expansion to a computer system by allowing an automatic medium exchange to manage a replaceable recording medium. CONSTITUTION:A medium automatic exchange device 50 extracts a medium from a medium storage position 60 in which media are stored, mounts it to a driver 40 and stores a driver number to a storage identification flag column corresponding to a storage medium number table 51. The driver 40 or the exchange device 50 informs it to a controller 30 that the medium on request is mounted. The controller 30 stores an address range of the medium to an address range column of a mount address range table 31 corresponding to the driver number. The controller 30 converts an address, a length, a requested operation and other information into order information, sends the said information to the driver 40 so as to control the operation requested by a host 10.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a removable storage medium management system for a computer system having a removable storage medium as a secondary storage mechanism.

``Prior Art'' In current computer systems, the secondary storage mechanism includes a control device and one or more drive devices connected thereto. In particular, when the recording medium is a removable medium, there is a secondary storage mechanism that also includes an automatic medium exchange device. The Wi controller receives commands regarding the operation to be performed, the transfer start address on the medium, the transfer length, etc. from the host via the bus.

All of this command information is converted into the necessary signals to control the transfer of data between the appropriate drives and other system elements. The drive device operates the recording medium, reads data from the recording medium and transfers the data to the control device, and writes data transferred from the control device to the recording medium. The automatic media exchange device receives commands related to media movement from the host or control device, mounts the specified media from the media storage location to the drive device, and performs T! &Mount from a moving device to a media storage position, or move from one media storage position to another.

On the other hand, when introducing a computer system, the system is usually designed to minimize the initial investment, taking into account the necessary processing performance, secondary storage capacity, etc. Therefore, from a cost standpoint, it is desirable to expand the system when the required secondary storage capacity, etc. increases.

In conventional known systems, media exchange is managed by the host, which determines on which media storage locations the required files are stored.

Therefore, it is necessary for the host to know the storage location of the media.
em)'s secondary storage routines. Furthermore, when the storage location of media is changed or the number of storage media is increased or decreased, it is necessary to change the secondary storage routine of the host O8, but the secondary storage routine is closely related to other processing routines. Therefore, changes to O3 are extensive and lead to increased costs. To solve this shortcoming.

There are known systems in which media management is performed by a controller. However, in an initially introduced system that does not require an automatic media exchange device, a control device having a media management function is used, resulting in an expensive initial investment. Also, to avoid this, when expanding from an initial system that does not require an automatic media exchange device to a system that has an automatic media exchange device.

The method of changing the control device requires double investment in the control device, which increases costs.

``Object of the Invention'' The present invention is to cause an automatic medium exchange device to manage a removable recording medium, to connect a host, a control device, and an automatic medium exchange device via a host interface bus;
It is characterized by adding a communication function for media exchange with an automatic media exchange device to the control device, and its purpose is to
The present invention aims to reduce the overhead of the secondary storage routine in 8, and to facilitate expansion from an initially introduced computer system that does not require an automatic medium exchange device to a computer system that requires an automatic medium exchange device.

Embodiment FIG. 1 shows an embodiment of the invention in which one or more hosts 1
It consists of a secondary storage mechanism 20 connected to 0.

The secondary storage mechanism 20 has one control device 30. Multiple drives! 40. In this embodiment, a secondary storage mechanism 2 including one automatic medium exchange device 50 has an automatic medium exchange device 50.
0 will be described, however, those skilled in the art will easily understand the secondary storage mechanism in the initial stage of installation, in which the automatic medium exchange device 50 is not developed, based on this embodiment.

Automatic media exchange device 50 includes a plurality of media storage locations 60, host 10. Control device 30. Automatic media exchange device 50 is connected by host interface bus 70 . The control device 30 and the plurality of drive devices 40 are connected by a known method. The control device 30 includes a mount address range table 31 and an automatic medium exchange device identification flag 32. The automatic medium exchange device 50 includes a storage medium number table 51.

FIG. 2 shows an example of the structure of the above-mentioned tables.

FIG. 2(a) shows the configuration of the mount address range table 31, in which the drive device numbers of a plurality of drive devices 40,
A mount identification flag for identifying whether or not a medium is mounted on the drive device 40 and an address range stored in the mounted medium are stored. The mount identification flag is:

For example, if the medium is not mounted, O is stored, and if it is mounted, 1 is stored. FIG. 2) shows the configuration of a storage medium number table 51, in which multiple medium storage positions
The medium storage position number 0, a storage identification flag for identifying whether or not a medium is stored in the medium storage position 60, and the medium number of the stored medium are stored. The storage identification flag contains, for example, 10 when the medium is stored.
0 is stored, and when no medium is stored, for example, O is stored. However, when the medium is not currently stored but is mounted on the drive device 40, the drive device number is stored. Although not shown in FIG. 2, the automatic medium exchange device identification flag 32 is a flag for identifying whether or not the automatic medium exchange device 50 is included in the secondary storage mechanism 20.

Initial settings for the above tables can be performed as follows. Regarding the storage medium number table 51, it is possible to obtain the correspondence between the medium storage position number and the medium number by taking out the mediums one by one from the medium storage position 60 at the time of initial setting of the system such as power-on, or by expanding or changing the system. When the automatic medium exchange device 50 is installed in the secondary storage mechanism 20, the correspondence between the medium storage position number and the medium number is obtained. Further, regarding the drive device number and mount address range table 31 stored in the storage identification flag of the storage medium number table 51, the correspondence between the drive device number, medium number, and address range is obtained at the time the medium is mounted on the drive device. Note that the automatic medium exchange device identification flag 32 of the control device 30 is set to indicate that the automatic medium exchange device is attached to the switch or nonvolatile storage element, etc. when the automatic medium exchange device 50 is installed in the secondary storage mechanism 20. 0, 31st! I is in the secondary storage mechanism 20 shown in FIG.

normal medium access operations (e.g. read).

This is a write operation) flow, and the normal medium access operation in the secondary storage mechanism 20 will be explained below with reference to FIG. If host IO issues a request to drive the media, host IO
0 derives the address and length at which the file should be stored or is stored using a known method from the file name set by the operator or program, the derived address and length, the required operation, and other information. is converted into command information and sent to the control device 30 via the host interface bus 70. The control device 30 checks whether the address range corresponding to the requested address and length is mounted on any of the plurality of drive devices 40 by referring to the mount address range table 31, and if it is mounted, the address range corresponding to the requested address and length is mounted. and converts the length, required operation, and other information into order information, sends it to the drive device i4G mounting the medium corresponding to the address range, and controls the operation requested by the host 10 using a known method. do. If the desired medium is not mounted on any of the plurality of drive devices 40, first refer to the mount identification flag in the mount address range table 31 to search for a drive device on which the medium is not mounted, and if it is not found, then the LRU (
The drive value W140 to be mounted is selected using a known appropriate method such as a Least Recently Used algorithm. The control device 30 checks the automatic medium exchange device identification flag 32 and determines whether it is an automatic medium exchange device! 50, and performs the processing described below. Incidentally, if you recognize that this is a secondary storage mechanism that does not include the automatic medium exchange device 50.

The host 10 is notified via the host interface bus 70 that the desired medium is not mounted on any of the plurality of drives 40 and, if necessary, the drive number to be mounted.

This embodiment is a secondary storage mechanism 2 including an automatic medium exchanger W50.
0, the controller 30 sends command information including the selected drive number, the address, and the length to the automatic media changer 50 via the host interface bus 70. The automatic medium exchange device 50 obtains the drive device 40 to be mounted from the drive device number, converts the address and length into a medium number, and refers to the storage medium number table 51 to determine whether the medium with the medium number is a plurality of media. It is checked whether it is stored in any of the storage locations 60. If the medium is not stored, the automatic medium exchanger 50 notifies the host 10 via the host interface bus 70 that the medium is not stored.

The host 10 performs necessary processing. If the medium is stored in any of the medium storage positions 60, the automatic medium exchange device 50 refers to the storage medium number table 51 to determine whether a medium other than the medium to be mounted on the drive device 40 is mounted. Find out. If a medium other than the target medium to be mounted is mounted on the drive device 40, refer to the storage medium number table 51 and select the medium storage position number where the medium should be stored.

The medium is demounted from the drive device 40 and stored in the storage location. Following this or.

If a medium other than the medium to be mounted is not mounted, the medium storage position 60 where the medium corresponding to the medium number to be mounted is stored is stored in the storage medium number table 5.
Obtained with reference to 2. The automatic medium exchange device 50 takes out the medium from the medium storage location 60 where the medium is stored,
It is mounted on the drive device 40, and the drive device number is stored in the corresponding storage identification flag column of the storage medium number table 51.

The drive device 40 or automatic medium exchange device 50 notifies the controller 30 that the requested medium has been mounted. The control device 30 stores the address range of the medium in the address range column corresponding to the drive device number of the mount address range table 31. The control device 30 receives the address, the length, and the requested operation.

The information on the pond is converted into order information and sent to the drive device 40, and the operation requested by the host 10 is controlled by a known method.

In the above embodiment, it has been described that the medium is specified by the address and length in the medium mount request from the control device 30 to the automatic medium exchange device 50.

The control device 30 may convert the address and length into a medium number, and the medium mount request may be specified by the medium number instead of the address and length.

The control device 30 may directly specify the medium to be demounted without storing the drive device number in the storage identification flag of the storage medium number table 51. in this way.

The formats of the information and tables included in the commands used here are merely examples, and can be arbitrarily designed depending on the specific implementation method of the present invention. moreover.

Although this embodiment has described a secondary storage mechanism having one control device and one automatic medium exchange device, two storage mechanisms having multiple control devices and multiple automatic medium exchange devices are also implemented. The examples will be easily understood by those skilled in the art.

"Effects of the Invention" As explained above, by having the automatic media exchange device manage the removable recording media, two
The overhead of the next storage routine is reduced. It also connects the host, controller, and automated media switching device via the host interface bus, and connects the automated media switching device via the host interface bus if the requested media from the host is not mounted on the drive. By incorporating a routine in the control device to request a media exchange, automatic media exchange is possible from an initial system that does not require an automatic media exchange device with the minimum amount of additional hardware built into the control device and the minimum amount of media exchange routines. Since it is easy to expand the system to a system that requires equipment, there is an advantage that the total cost of constructing a computer system can be reduced.

2. In the present invention, the host, control device, and automatic medium exchange device are connected via the host interface bus, so multiple control devices and multiple automatic medium exchange devices can be easily connected to the secondary storage mechanism. A system configuration with excellent expandability is possible.

[Brief explanation of drawings]

FIG. 1 is an embodiment of the present invention, FIG. 2 is a configuration diagram of the tables shown in FIG. 1, and FIG. 3 is an operational flow during normal medium access in FIG. 1. 10...Host 20...Secondary storage mechanism 30...Control value W 40...Drive device 50...Medium automatic exchange device 60...Medium storage location 70...Host interface bus 32...Flag 31.51...Flag 4+3 (cA,) (b) Year 2 Figure

Claims (1)

[Claims] A secondary storage mechanism for a computer system having a removable recording medium, comprising a control device, a drive device, and an automatic medium exchange device, the control device and the automatic medium exchange device being connected via a host interface bus. and means for identifying whether or not the secondary storage mechanism has the automatic medium exchange device;
means for storing an address range corresponding to a file recorded on the recording medium and a drive device number of the drive device in which the recording medium is mounted; The control device is provided with means for determining whether or not there is a recording medium in the secondary storage mechanism, and means for requesting the automatic medium exchange device to exchange a medium via the host interface bus, A replaceable recording medium, characterized in that an automatic medium exchange device is provided with means for storing a storage position number in which the recording medium is stored, and means for checking the storage position of the recording medium and exchanging the recording medium. Management method.