JPH04287249A - System for exclusively controlling common type extended storage device - Google Patents

Abstract

PURPOSE:To efficiently use a common type extended storage device by reducing the waiting time for the storage device and, especially, waiting time for access when referring operations are frequently performed. CONSTITUTION:Since an operating state storing area is provided in the control section of a common type extended storage device 1, the storage device 1 can be exclusively controlled only in the 'unused state' and operating states for 'reference' and 'updating' and the device 1 can be accessed simultaneously from plural systems.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exclusive control method for a shared expanded storage device, and more particularly to an exclusive control method for a shared expanded storage device when shared by a plurality of systems.

0002

2. Description of the Related Art In a conventional exclusive control method for a shared expanded storage device, when a system uses a shared expanded storage device, it executes an instruction to exclusively use the shared expanded storage device, and then uses the shared expanded storage device. When it is finished, it executes an instruction to release the shared extended storage device. This is 1
Prevents one system from using the shared extended storage device for an update operation while one system is using the shared extended storage device for a reference operation, and updates the data area that the reference operation is being performed or the system that is attempting to reference. 1.
While one system is exclusively using the shared expanded storage device, exclusive control is performed to prevent other systems from using the shared expanded storage device.

0003

[Problems to be Solved by the Invention] The above-mentioned exclusive control method for a shared extended storage device is such that when one system is using the shared extended storage device exclusively and only for reference operations, another system cannot control the shared extended storage device. Even if a shared extended storage device is used only for reference operations, as in The disadvantage is that type-extended storage cannot be used.

0004

[Means for Solving the Problems] The present invention provides a system that is located below the main memory, performs data transfer with the main memory, and uses an exclusive control method to control exclusive use and release operations from multiple systems. In an exclusive control method for a shared extended storage device that has a function that allows it to be used by multiple systems at the same time only when the system in use is in a reference operation,
means for providing an operating state storage area in the control unit of the shared expanded storage device and storing information on three operating states, an unused state, a reference state, and an updated state in the operating state storage area; means for performing control such that use of the shared expanded storage device is permitted only when information in the operation status storage area is not "updated" when the shared expanded storage device is used only for reference operations; and the shared expanded storage device; When access to the storage device ends and the information in the operating state storage area is changed to "unused" and the shared expanded storage device is released, another of the systems uses the shared expanded storage device. By managing information indicating three operating states in the operating state storage area provided in the control unit, simultaneous use of reference operations from a plurality of systems is possible. It is something to do.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a configuration diagram illustrating a shared expanded storage device to which the exclusive control method for shared expanded storage devices of the present invention is applied and two systems for accessing the shared expanded storage device. FIG. FIG. 3 is a detailed flowchart of the exclusive command (step 1) in FIG. 2, and FIG.
2 is a detailed flowchart of the release command (step 3) of FIG.

The shared expanded storage device 1 is physically connected to the main storage control device 3a (3b), and is located below the main storage device 2a (2b) in the storage hierarchy.
(2b) Data transfer is basically used. It is also assumed that the shared expansion storage device 1 has a function that allows only reference operations from a plurality of systems to be performed simultaneously under the control of the control section. The control unit has an operating state storage area, and there are three types of operating state information: "unused, referenced, and updated." In the initial state, "unused" information is held, and the system stores the operating state. If the operation is a reference operation, the information is changed to ``reference'', and if the operation is an update, the information is changed to ``update'', and when the operation ends and the shared expanded storage device is released, the information is changed to ``unused''. It holds information on the operating status of any of the three.

[0008] System A (B) is a shared expansion storage device 1.
The operation when attempting to use the ``dedicated'' instruction (step 1) is executed as shown in FIG.

The above operation will be explained in detail with reference to FIGS. 3 and 4. In the case of an operation in which system A uses shared expanded storage device 1 that is not used anywhere else, when system A executes the exclusive instruction (step 1), whether the shared expanded storage device 1 is occupied by another system or not. If it is not occupied by another system (step 11), system A stores information about the operation to be performed in the operation status storage area of the control unit of the shared extended storage device 1 (step 13), and then shares the information. Use type extended storage (step 2). After that, when the use of the shared expanded storage device 1 is finished and the release command (step 3) is executed, a check is made to see if it is being used by another system (step 31), and if it is not in use, unused information is stored in the operating status storage area. is stored (step 32), and the process ends.

[0010] System A is another system (system B)
In the case of an operation that uses the shared expanded storage device 1 currently in use, when system A executes the exclusive command (step 1), it checks whether the shared expanded storage device 1 is being used exclusively by another system (step 1). 11) In this case, since shared expansion storage device 1 is being used from system B, check whether the operation of system A is the reference operation (step 1).
2) If it is not a reference operation, the shared extended storage device 1 cannot be used and the exclusive instruction ends (step 16). When the operation of system A is a reference operation, the information in the operation status storage area of the control unit of the shared expanded storage device 1 is checked (step 14), and system B is currently using the shared expanded storage device 1 for the reference operation. If it is not dedicated, the shared extended storage device 1 cannot be used and the dedicated instruction ends (step 16), but if it is dedicated for reference operation, the shared extended storage device 1 can be used. (Step 15). After that, the use of the shared expansion storage device 1 is completed and the release command (
When step 3) is executed, it is checked whether another system is in use (step 31), and if it is not in use, unused information is stored in the operating state storage area (step 32), and the release command ends. If it is in use, the release command ends without storing unused information in the operating state storage area.

[0011]

[Effects of the Invention] As explained above, the present invention provides an operating state storage area in the control unit of a shared extended storage device, and excludes the shared extended storage device in the operating state of “unused, referenced, updated”. By controlling the system so that multiple systems can access only reference operations at the same time, it is possible to reduce the waiting time for the shared expanded storage device, especially when reference operations are frequently performed. This has the effect that the shared extended storage device can be operated efficiently.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram illustrating a shared expanded storage device to which an exclusive control method for shared expanded storage devices of the present invention is applied and two systems that access the shared expanded storage device.

FIG. 2 is a flowchart illustrating the operation of the system for exclusive use and release of a shared expanded storage device.

FIG. 3 is a detailed flowchart of the proprietary instruction of FIG. 2;

FIG. 4 is a detailed flowchart of the release command of FIG. 2;

[Explanation of symbols]

1. Shared expansion storage device 2a Main memory 2b Main memory 3a Main memory control device 3b Main memory control device 4a Central processing unit 4b Central processing unit 5a Input/output control device 5b Input/output control device A System B System

Claims (1)

[Claims] Claim 1: A storage device located below the main storage device, which performs data transfer with the main storage device, and is shared using an exclusive control method for exclusive use and release operations from multiple systems, and the operation of the systems using it is controlled. In an exclusive control method for a shared extended storage device that has a function that allows use by multiple systems at the same time only during a reference operation, an operating state storage area is provided in a control unit of the shared extended storage device to store the operating state. means for retaining information on three operating states, an unused state, a reference state, and an updated state, in an area; and information on the operating state storage area when one of the systems uses the shared extended storage device only for reference operations; means for performing control such that the use of the shared expanded storage area is permitted only when the shared expanded storage area is not "updated";'', and means for checking whether another one of the systems is using the shared expanded storage device when attempting to release the shared expanded storage device; An exclusive control method for a shared extended storage device that enables simultaneous use during reference operations from multiple systems by managing information indicating three operating states of a state storage area.