JPH0774982B2 - Multiple recording method of external storage device - Google Patents

Description

DETAILED DESCRIPTION [Overview] An internal storage device shared by an external storage device and a plurality of data stored in a predetermined storage area of the internal storage device are multiplexed so as to be uniformly written in all of them. An external storage device, a channel device provided for each external storage device, which analyzes an input / output instruction issued by an input / output instruction designating unit, and activates the external storage device, and an input / output instruction for the external storage device, Regarding a multiplex recording method of an external storage device having an input / output instruction designating means for issuing a continuous instruction for executing a plurality of input / output instructions in succession, the multiplexed external recording device includes the continuous instruction via a channel device. When issuing an I / O command, the channel device is capable of executing the I / O command without being aware of the multiplexing of the external recording device. Then, the continuous instruction issued by the input / output instruction designating means is analyzed, the instruction is executed to make the external storage device function, and the execution of the instruction is interrupted at the time when the synchronization is required based on the sharing of the internal storage device. A synchronization waiting notification to that effect is sent to the restart instruction means, and the instruction analysis execution means for restarting the instruction suspended by the restart instruction notification from the restart instruction means and the synchronization wait notification from the instruction analysis execution means are multiplexed. It is configured to have a restart instruction means for issuing a restart instruction notification for restarting the execution of the instruction to the instruction analysis execution means when received from all the external storage devices.

[Industrial application field]

The present invention relates to a multiplex recording method of an external storage device, which increases the reliability of the system by writing the same contents to a plurality of disk devices, and in particular, it is multiplexed with an internal storage device shared by the external storage devices. A plurality of external storage devices, a channel device that analyzes the input / output instructions issued by the input / output instruction designating means and activates the external storage device, and an input / output instruction designating means that issues the input / output instructions to the external storage device. The present invention relates to a multiplex recording method of an external storage device having the same.

[Conventional technology]

Conventionally, for example, as shown in FIG. 4, a main storage device 45, two-multiplexed disk devices 44a and 44b for writing data held in a predetermined storage area in the main storage device 45, and a disk device 44a. An external storage device having input / output command instructing means 41 for issuing an input / output command to / from each other, and channel devices 46a, 46b for operating the disk devices 44a, 44b by analyzing the command issued by the input / output command instructing means 41. There was a multiple recording system.

When performing the multiplex recording to write the same contents to the two disk devices 44a and 44b, the device is performed by issuing the same write command to each of the two disk devices 44a and 44b to be multiplexed. It was At this time, issuing the continuous command to the channel device requires the channel device to be aware of the multiplexing of the external recording device, which is not easy to realize.

[Problems to be Solved by the Invention]

By the way, in the conventional two-multiplex multiplex recording system shown in FIG. 5, for example, the disk device A54a and the disk device B54b share the storage area 55a in the main memory device 55, and the disk device A54a and the disk device B54b respectively. On the other hand, consider a case in which an instruction having a "write-read" instruction chain (an instruction group in which a plurality of input / output instructions are continuously executed) is issued. Here, it is assumed that the operation of the disk device A54a precedes.

First, the data A which is the content of the storage area 55a is written in the disk device A54a (FIG. 5 (A)). Next, the disk device A54a executes a read command which is an instruction chain of the write command, and transfers the data B which is the read content from the disk device A54a to the storage area 55a (FIG. 5 (B)). Here, the command issued to the disk device B54b (disk device
(Same as issued to A54a) is started and storage area 55
Write the contents of a to the disk device B54b. At this time, the contents of the storage area 55a are rewritten to the data B by the read command to the disk device A54a.
It is not possible to write the same data A to the disk device B54b, which is a multiplexed disk of the above (FIG. 5 (C)).

Therefore, in order to handle the instruction chained instructions, it is necessary to synchronize the input / output instructions between the disk device A54a and the disk device B54b.

Therefore, the present invention provides a method of synchronizing the execution of an instruction issued to each external storage device when the storage area 55a in the internal storage device 55 is shared between the multiplexed external storage devices. It was made for the purpose.

[Means for Solving the Problems]

In order to solve the above technical problems, the present invention provides an internal storage device 5 shared by external storage devices 4a, 4b, to 4n and a predetermined storage area of the internal storage device 5 as shown in FIG. A plurality of external storage devices 4a, 4b, to 4n, which are multiplexed to write the held data in the same manner, and input / output command instructing means 1 are provided for each of the external storage devices 4a, 4b, to 4n. Channel devices 6a, 6b, to 6n for operating the external storage devices 4a, 4b, to 4n by analyzing the input / output instructions issued by the external storage device 4 and
An input / output command for a, 4b, to 4n, and an input / output command instructing means 1 for issuing a continuous command for executing a plurality of the input / output commands in succession. The continuous instruction issued by the instruction instructing means 1 is analyzed, the instruction is executed to make the external storage devices 4a, 4b, to 4n function, and the instruction is executed at the time when synchronization is required based on the sharing of the internal storage device 5. Instruction analysis execution means 2a, 2b, to 2n for interrupting, issuing a synchronization wait notification to that effect to the restart instruction means 3, and restarting the interrupted instruction by the restart instruction notification from the restart instruction means 3 and instruction analysis execution All the external storage devices 4a, 4b, to which the synchronization waiting notifications from the means 2a, 2b, to 2n are multiplexed
4n, the instruction analysis execution means 2a, 2b, and 2n have restart instruction means 3 for issuing a restart instruction notification for restarting the execution of the instruction.

[Action]

The multiple recording method of the external storage device according to the present invention operates as follows. As shown in FIG. 1, first, the input / output command instructing means 1 issues a continuous command which is an input / output command for the external storage devices 4a, 4b, to 4n and which continuously executes a plurality of the input / output commands. . Here, in order to make the explanation easier to understand, for example, in the case where the input / output instruction designating means 1 issues a continuous instruction of "write instruction-read instruction" to all the multiplexed external storage devices 4a, 4b, to 4n. explain. In this case, the write command is multiplexed and the internal storage device 5 is used.
Data in a specified storage area of each external storage device
It is an instruction to write the same in 4a, 4b, to 4n. Then, the instruction analysis execution means 2a, 2 provided in the channel devices 6a, 6b, to 6n.
In b, to 2n, the external storage devices 4a, 4b, to 4n are operated based on the instruction issued by the input / output instruction designating means 1. By the way, when the same storage information stored in a predetermined storage area of the internal storage device 5 is being written to the external storage devices 4a, 4b, to 4n, and there is a command to read the storage area, etc. , A write instruction and a read instruction are synchronized with each other (when a predetermined storage area of the internal storage device 5 is shared as a read area or a write area, the read instruction is executed until all the write instructions are completed. When this is done, the area is destroyed, so synchronization is required for that.) At that point, the execution of the read instruction is interrupted and the synchronization wait for that is required. The notification is sent to the restart instruction means 3. Restart instruction means 3
Then, the instruction analysis executing means 2a, 2b, ~ 2n, when receiving the synchronization wait notification from the instruction analysis executing means 2a, 2b, ~ 2n from all the multiplexed external storage devices 4a, 4b, ~ 4n On the other hand, a restart instruction notification is issued to instruct restart of instruction execution. Based on the restart instruction notification, the execution of the read command suspended above is restarted. At this point, the instruction execution is synchronized, and it is not necessary to save the information in the shared storage area, and there is no problem in executing the read instruction.

[Execution example]

 Subsequently, an execution example of the present invention will be described.

FIG. 2 is a block diagram according to an execution example of the present invention. As a configuration, the control unit 26 comprises a central processing unit, and a main storage device.
Perform a series of processing according to the control program written in part of 25. The main storage device 25 as the internal storage device 5, which can be directly accessed from the central processing unit, stores the read data from the disk devices 24a and 24b. The input / output command instructing means 21 issues to the channel devices 26a, 26b commands that are input / output commands to the disk devices 24a, 24b and that execute a plurality of the input / output commands in succession (hereinafter referred to as "command chain"). The channel devices 26a and 26b are provided with instruction analysis execution means 22a and 22b, respectively, and analyze the instructions issued by the input / output instruction instruction means 21 to analyze the disk devices.
Operate 24a and 24b. On the other hand, the instruction analysis execution means 22a, 22b
In step 1, the execution of the instruction is interrupted at the time point when the synchronization is necessary, the synchronization waiting notification is sent to the restart instruction means 23, and the execution of the interrupted instruction is restarted based on the restart instruction notification from the restart instruction means 23. The restart instruction means 23 is an instruction analysis execution means 22a,
When the synchronization wait notifications from both 22b are received, the instruction analysis execution means 22a and 22b are notified of the instruction execution restart instructions. The disk devices 24a and 24b as the external storage devices 4a and 4b are composed of disk units and store and store a large amount of data.

Next, the operation will be described. Here, as an example, a case will be described in which the input / output instruction designating means 21 issues a continuous instruction in the instruction chain of "write-read" to the channel device 26a. First, the instruction analysis executing means 22a analyzes the instruction issued by the input / output instruction instructing means 21, and the disk device 24
Instruct a to only execute write instructions. When the execution of the write instruction is completed and the report is received from the disk device 24a, the instruction analysis execution means 22a puts the next read instruction in a wait state, and the restart instruction means 23 is notified of the synchronization wait interrupt (synchronization wait interrupt). It corresponds to the waiting notification).

The restart instruction means 23 outputs a restart instruction notification to each of the instruction analysis execution means 22a, 22b at the time point when synchronization wait is notified by the synchronization wait interrupt from the two multiplexed instruction analysis execution means 22a, 22b. Upon receiving the restart instruction notification from the restart instruction means 23, the instruction analysis execution means 22a restarts the read instruction in the waiting state and instructs the disk device 24a to operate. When the execution of the instruction is completed in the disk device 24a, the channel device 26c which has received the report, after receiving the notification of the completion, makes an interrupt to the control unit 26 notifying the completion of execution of the instruction (not shown). Therefore,
The channel devices 26a and 26b can perform the synchronization only by restarting the command based on the restart instruction notification without being aware of whether the disk devices 24a and 24b controlled by the channel devices 26a and 26b are multiplexed.

FIG. 3 shows a time chart showing the operation when the disk device is multiplexed in four. Here, the write command and the read command for the disk devices A to D are continuously executed. Further, each disk device waits for synchronization until the write command for all the disk devices is completed, and when the last synchronization wait interrupt from the disk device C is completed, a restart instruction is notified and the interrupted read command is restarted. It indicates that when the instruction is executed and the execution of the instruction is completed, a notification to that effect is given by an instruction end interrupt. The operations of the respective channel (disk device) devices are all performed in the same procedure, and the synchronization is performed without the channel device being aware of the existence and operation of the multiplexed devices other than itself.

〔The invention's effect〕

As described above, in the present invention, the instruction analysis executing means provided in the channel device interrupts the execution of the instruction at the time when the synchronization is required, and notifies the restart instruction means of the waiting for the synchronization,
On the basis of the restart instruction notification from the restart instruction means at the time of receiving the synchronization wait notification from all the multiplexed external storage devices, the interrupted instruction is restarted to achieve synchronization.

Therefore, when each channel device executes an instruction, it can be synchronized without being aware of whether or not the external storage device controlled by the device is multiplexed. Therefore, the external storage device can be easily multiplexed, which is useful.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention, FIG. 2 is a block diagram according to an execution example, FIG. 3 is a time chart showing an operation in the case of 4-multiplexing, FIG. 4 is a block diagram according to a conventional example, and FIG. The figure is an explanatory view according to a conventional example. 1,21 ...... Input / output command instruction means, 2a, 2b, ~ 2n, 22a, 22b ......
Instruction analysis execution means, 3,23 ... Restart instruction means, 4a, 4b, ~ 4n
(24a, 24b) ... External storage device (disk device), 5 (2
5) ... Internal storage device (main storage device), 6a, 6b, ~ 6n, 26a,
26b ... Channel equipment

Claims (1)

[Claims] 1. An internal storage device (5) shared by external storage devices (4a, 4b, to 4n) and data held in a predetermined storage area of the internal storage device (5) are all the same. Multiple external storage devices (4a, 4b,
~ 4n) and each external storage device (4a, 4b, ~ 4n), the external storage device (4a, 4b, ~ 4n) is analyzed by analyzing the input / output command issued by the input / output command designating means (1). Channel devices (6a, 6b, ~ 6n) that operate the computer, and external storage devices (4a, 4b, ~ 4n)
An input / output command to the external storage device, the input / output command specifying unit (1) issuing a continuous command for executing a plurality of the input / output commands in succession. 1) Analyzing the continuous instructions issued and executing the instructions to make the external storage devices (4a, 4b, to 4n) function, and at the time when synchronization is required based on the sharing of the internal storage device (5). The instruction analysis execution means (2a, 2b, 2a, 2b, 2b, 2b, ~ 2n) and the instruction analysis execution means (2a, 2b, ~ 2n) from all the multiplexed external storage devices (4a, 4b, ~ 4n), the instruction analysis execution means (2a, 2b, ~ 2n) (2a, 2b, ~ 2n) restart instruction notification to restart the execution of the instruction Cormorant restart instruction means (3) and the multiplex recording device of the external storage device characterized in that it comprises a.