JPH0476187B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a plurality of cartridge tape devices, and a cartridge selection and transportation device that transports cartridge tapes from a cartridge warehouse to the cartridge tape devices and loads or unloads them. Concerning an automatic tape library system that is composed of a control device, etc. that controls these devices, and is capable of transferring a large amount of information,
In particular, by commonly controlling the cartridge tape device and the cartridge selection and transportation device that are under the control of the control device, the effective data processing speed of the cartridge tape device can be increased, and the cartridge selection and transportation device can be given efficient tape handling operation instructions. This invention relates to a control method for an automatic tape library system that enables this.

In recent years, the amount of information to be processed in information processing systems has continued to increase, and this information is temporarily or long-term stored on magnetic disks or magnetic tapes during or after processing.
Although magnetic disks have the advantage of allowing random access to information, they are relatively expensive and have limitations in terms of installation space.

On the other hand, although magnetic tape has the advantage of being relatively cheap, it can only be accessed sequentially, making it inconvenient to edit information. Moreover, especially when handling a large amount of information, there are problems such as storage management of magnetic tapes and mistakes when loading magnetic tapes. Mass storage systems have been developed to solve these problems.

This large-capacity storage system is an automatic tape library system that automates tape handling based on a highly cost-effective, high-performance cartridge tape device that runs tapes in streaming mode.

In other words, the cartridge tape device is operated in a streaming mode in which the magnetic tape is continuously run at high speed without stopping due to gaps between data blocks, thereby making it possible to transfer information at high speed.

However, for this reason, it is important not to reduce processing efficiency in controlling the cartridge selection and transportation device that transports cartridge tapes between cartridge tape devices and between cartridge tape devices.

[Conventional technology]

FIG. 2 is a block diagram showing an example of the configuration of an automatic tape library system.

The control devices 1A, 1B and 2A, 2B are each connected to, for example, a block multiplexer channel (BMC) of a host device, and are controlled by a central processing unit via the block multiplexer channel to control data transfer.

Further, the control devices 1A and 1B include, for example, a plurality of cartridge tape devices 8, 9, 10, and 11, and a cartridge selection and transportation device (ACC) that selects and transports the cartridge tapes used by the cartridge tape devices 8 to 11. An ACC control device 3 that controls the cartridge selection and transportation device 7 and an AC controller 4 that controls the cartridge selection and transportation device 7 are connected.

Further, the control devices 2A, 2B include, for example, a plurality of cartridge tape devices 13, 14, 15, 16,
ACC control device 4 that controls the cartridge selection and transportation device 7 that selects and conveys the cartridge tapes used by the cartridge tape devices 13 to 16; and ACC that controls the cartridge selection and transportation device 5;
Control device 3 is connected.

Cartridge tape devices 8 to 11 are control device 1
It is commonly controlled (device call) from A and 1B. Further, the cartridge tape devices 13 to 16 are commonly controlled by control devices 2A and 2B. The cartridge selection and conveyance devices 5 and 7 are each controlled by the control device 1.
Commonly controlled from A, 1B and 2A, 2B.

The control devices 1A, 1B and 2A, 2B transfer cartridge tapes necessary for writing/reading operations to the cartridge tape devices 8 to 11 and 13 to 16 via the ACC control devices 3 and 4 to the cartridge selection and transportation device. 5 and 7, respectively, and instructs the cartridges to be sent and received from the cartridge warehouse 12 via the cartridge access station (CAS) 6, and transported to the cartridge tape devices 8-11 and 13-16.

The cartridge tape devices 8 to 11 and 13 to 16 to which the cartridge tape is transported load the cartridge tape and perform write/read operations.

After a series of writing/reading processes, the cartridge tape is transferred to cartridge tape devices 8 to 1.
1 and 13 to 16, transported by cartridge selection and transport devices 5 and 7, and returned to cartridge tape warehouse 12.

Cartridge tape devices 8-11 and 13-1
6 is characterized in that its tape running mode is based on streaming operation, and it achieves high performance by processing large amounts of data at once by chaining a large number of data block processing instructions. .

Therefore, when transferring data to and from the block multiplexer channel, the high performance is achieved by occupying the connection channel for a relatively long time through command chain processing.

Since the cartridge selection and transportation devices 5 and 7 transport cartridge tapes as described above, the amount of data processing between them and the control device 1 or 2 is small, but it takes a long time to execute instructions that instruct tape processing. It has the characteristics of

Therefore, cartridge tape devices 8 to 11 and 1
In order to efficiently perform data processing on the cartridge tapes loaded in the cartridges 3 to 16, an instruction to transport the cartridge tape to the cartridge tape device is given in advance to the cartridge selection and transport device 5 or 7. There is a need.

As mentioned above, since the cartridge selection and transportation device requires a long time from receiving a command to completing execution, the control device gives the command to the cartridge selection and transportation device and then temporarily shifts to control of other devices. In this case, when control of a cartridge tape device that operates with a connection channel for a long period of time is started, the control operation of the cartridge tape device becomes exclusive.

For example, since the cartridge tape device 8 exhibits high performance as described above, when it starts operating in streaming mode, it can report the completion of processing and issue the next instruction within the short time it takes for the magnetic head to pass through the gap between the data blocks. If you do not receive it, you will not be able to maintain continuous running.

Therefore, the control device 1A is occupied with analysis of the command chain given from the block multiplexer channel of the host device and data transfer control. This also applies to the control devices 1B and 2B.

[Problem that the invention seeks to solve]

For example, when the control device 1A is occupied with controlling the cartridge tape device 8 as described above, the control device 1A
Even if the operation of the cartridge selection and transportation device 5 instructed by A is completed, there is a possibility that the operation will be left unattended without being notified to the higher-level device. Further, even if the unloading operations of the other cartridge tape devices 9 to 11 instructed by the control device 1A are completed, there is a possibility that the cartridge selection and transportation device 5 is not instructed to take out and transport the cartridge tape and is left unloaded. be.

Furthermore, if data processing for the cartridge tape device 8 continues, even if a new I/O request to the cartridge selection and transportation device 5 occurs, the control device 1A is in a busy state.
The I/O request is left until the cartridge tape device 8 completes its processing.

In the above case, there is a problem in that efficient handling of cartridge tapes is no longer performed and the overall processing capacity of the automatic library system is reduced.

[Means for solving problems]

The above problem is that in an automatic tape library system, there is a means for detecting that the data transfer processing of a cartridge tape device has continuously processed a specified amount of data, and a means for detecting that a cartridge tape device other than the cartridge tape device or a cartridge selection and transport device. means for detecting an instruction end signal, and if the instruction end signal is detected when the data transfer process has completed a specified amount, temporarily discontinuing continuous processing of the cartridge tape device during the data transfer process; If the instruction end signal is not detected,
The problem is solved by a control method for an automatic tape library system that reports an error when the next data processing is instructed.

[Effect]

That is, when a cartridge tape device processes a certain number of data blocks and detects an operation end signal from another cartridge tape device or cartridge selection transport device, the control device changes the operation of the cartridge tape device under control. temporarily suspended,
The end of the operation is reported to the host device via an interrupt, thereby enabling the host device to issue a command to another cartridge tape device or cartridge selection transport device whose operation has ended. After a predetermined period of time has elapsed, it is possible to resume and continue the temporarily interrupted data transfer process for the data block.

In addition, if an operation end signal is not detected from another cartridge tape device or cartridge selection transport device, an error is reported, the command chain instruction from the host device is temporarily terminated, and the other cartridge tape device or cartridge selection transfer device is stopped. This allows new commands to be issued to the transport device.

〔Example〕

In the present invention, when the cartridge tape device completes writing/reading of a specified number of N blocks of data in the streaming mode, the control device
At the time when the command to process the block is received from the host device, an interrupt is generated to report the completion of the operation from another cartridge tape device that has instructed unloading or from the cartridge selection and transport device that has instructed tape transportation. If the signal is present,
After reporting to the host device that the processing of the N+1 block at the address of the cartridge tape device will be forcibly interrupted, the state of the interrupt signal is preferentially reported.

and a fixed time delay (e.g., corresponding to the repositioning time of the magnetic head when the streaming operation of a cartridge tape device is interrupted).
After that, an interrupt requesting restart of processing of block N+1 is sent to the host device again. In this case, if a new command is issued from the higher-level device to the other cartridge tape device or cartridge selection transport device that has reported the completion of the operation within the predetermined delay time, that command is processed.

In addition, when the cartridge tape device completes the data writing/reading process for a specified number of N blocks in the streaming mode, if a command end signal is not detected from another cartridge tape device or cartridge selection transport device, the cartridge tape device If continuous processing continues based on command chain instructions for the block, when a processing command for the N+1 block is received, an error report is sent to the higher-level device at startup, and the software is instructed to issue the same command during error recovery processing. do.

As a result, the command chain instruction is temporarily terminated, and it becomes possible to issue instructions to other devices. If there is a command queue prepared based on the status report of the operation end interrupt signal reported preferentially as described above, it is issued by the host device. Therefore, after the control device executes the processing of this command queue,
Processing continues from the N+1 block issued by the host device again.

By controlling in this way, the control device can control other cartridge tape devices or cartridge selection and transportation devices that have completed their operation.

FIG. 1 is a block diagram of a circuit showing one embodiment of the present invention, in which control devices 1A, 1B and 2A of FIG.
It is provided inside 2B. Therefore, the reference numerals with '' indicate those provided in other control devices.

The processor 17 sends a device selection code to the register 18, which indicates the device to be controlled, that is, the cartridge tape device or the cartridge selection transport device.
Set to . This device selection code is sent to the device selection circuit 21 and multiplexer 22. The device selection circuit 21 simultaneously selects the register 18
The device specified by the device selection code, for example, the #1 device, is selected by the selection sequence instruction signal given through the device selection code.

At this time, check the state of the reserved signal RSVD1 input from the receiver 27, which will be described later, and if this signal RSVD1 does not indicate that it is already under exclusive control from another control device, the #1 device is connected to terminal A. If so, the device selection circuit 21 sends to the terminal A, via the driver 23, a signal SLOK#1 that allows the #1 device to be exclusively occupied and controlled.

At the same time, the device selection circuit 21 is an OR circuit 31.
The SLOK#1 signal is also sent to the driver 28 via the SLOK#1 signal.
The driver 28 sends the SLOK#1 signal to the receiver 27' via the terminal C and the terminal C' of another control device.
Send as RSVD1 signal. Therefore, the device selection circuit 21' of the other control device can know that device #1 is under exclusive control.

Terminal A is the terminal for device #1 and other control devices
Connected to A′. The receiver 24 is the SLOK
#1, the signal, and the interrupt signal from the device are sent to the multiplexer 22. Therefore, the processor 17 sends the device selection code to the multiplexer 22 via the register 18.
By switching, the presence or absence of an interrupt signal from the device can be detected.

The number of data blocks processed by the cartridge tape device is stored in the register 20 from terminal E.
When the value of the register 20 reaches the specified number N, the processor 17 sends a device selection code to the multiplexer 22 and checks whether there is an interrupt signal from a device other than device #1.

For example, if the interrupt signal RDYn is rising via the receiver 26 via the terminal B, the processor 17 notifies the host device via the block multiplexer channel that the processing of the N+1 block will be interrupted. and the reserved signal in register 19.
Set RSV1.

This RSV1 signal is passed through the OR circuit 31, the driver 28, and the terminal C of the other control device.
Sent to C′. This RSV1 signal is device #1
indicates to other control devices that it continues to be under exclusive control.

Subsequently, the processor 17 resets the register 18 and further sets a device selection code for selecting device n. Driver 2 in the same manner as above
SLOKn signal from 5 passes through terminal B to device #n
and is sent to terminal B' of another control device. SLOKn
The signal passes through the OR circuit 32 and enters the driver 30.
is sent via terminal D to terminal D' of another control device,
The receiver 29' sends out the RSVDn signal to the device selection circuit 21'.

At the same time, the RSVn signal is also sent to the terminal D via the OR circuit 32 and the driver 30. Processor 17 processes a new instruction for device n from the host device via the block multiplexer channel as described above. Then, after waiting for a certain period of time as described above, a request is made to resume data processing for N+1 block. Then, reset the register 19 to release the device #n, send the selection code of the device #1 to the register 18 again, and
+1 block of data is processed.

As mentioned above, when the value of the register 20 reaches the specified number N, the processor 17 checks whether there is an interrupt signal from a device other than device #1, and if there is no interrupt signal, it sends an error to the host device via the block multiplexer channel. Report and temporarily terminate the command chain.

〔Effect of the invention〕

As explained above, the present invention prevents, in an automatic tape library system, the control device from being occupied by the streaming mode operation of one cartridge tape device and becoming unable to control the cartridge selection and transportation device or other cartridge tape devices. Furthermore, since it is possible to issue a new I/O command by terminating the command chain, it is possible to achieve both efficient tape handling and high-speed data processing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a circuit showing one embodiment of the present invention, and FIG. 2 is a block diagram showing an example of the configuration of an automatic tape library system. 1A, 1B, 2A, 2B are control devices, 3, 4 are
ACC control device, 5 and 7 are cartridge selection and transportation devices, 6 is a cartridge access station,
8 to 11 are cartridge tape devices, 12 is a cartridge warehouse, 13 to 16 are cartridge tape devices, 17 is a processor, 18 to 20 are registers, 21 is a device selection circuit, 22 is a multiplexer, 23, 25, 28, 30 is the driver, 2
4, 26, 27, 29 are receivers.

Claims (1)

[Claims] 1. Control a plurality of cartridge tape devices, a cartridge selection and transportation device that transports and loads or unloads cartridge tape from a cartridge warehouse to the cartridge tape devices, and the cartridge tape device and the cartridge selection and transportation device. In an automatic tape library system comprising a control device, etc., means for detecting that data transfer processing of a cartridge tape device has continuously processed a specified amount of data, and a cartridge tape device other than the cartridge tape device or cartridge selection transportation. means for detecting an instruction end signal of the device, and if the instruction end signal is detected when the data transfer process has completed a specified amount, the continuous processing of the cartridge tape device during the data transfer process is temporarily stopped. If the instruction end signal is not detected, when the next data processing is instructed,
A control method for an automatic tape library system characterized by error reporting.