JPH05204760A - Control system for virtual computer system - Google Patents

Abstract

PURPOSE:To enable real memory exchange while operating a virtual computer. CONSTITUTION:This system is provided with a means (1-4) to translate an address from a virtual address to a real address by an address translation table in an operating system, means (1-5) to make this real address correspondent to the address of a main memory by a management table, means (1-9) to judge the move of a memory between OS by checking the use condition of the real memory in the operating system managed by a managing program at fixed intervals, changing means (1-6) to change the real memories allocated to the respective operating systems by changing the management table when the move is required, means (1-7-1 and 1-7-2) to report the real memory changed by this changing means by the operating system, and means (1-8-1 and 1-8-2) for the reported operating system to change the memory based on the reported contents.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for a virtual computer system when the virtual computer system is realized in an electronic computer system.

[0002]

2. Description of the Related Art A plurality of operating systems and a management program for managing the plurality of operating systems are provided, and the plurality of operating systems are operated on one computer system under the control of the management program. The address conversion method in the virtual computer system is roughly divided into two methods.

(1) There is an address conversion method using a shadow page table. In this address translation method, on a real computer (not a virtual computer), the mapping of virtual addresses and real addresses must be defined by an address translation table managed by the operating system, and the translation process is a dynamic address translation function (DAT). Is carried out using. However, in a virtual machine system, multiple virtual machines run at the same time, so the same address as the real address is required for each virtual machine, and there is not enough space to accommodate multiple machines with real addresses. Or Therefore, in the virtual computer system, the real address on the virtual computer is also virtualized, and the virtual computer monitor manages the mapping between the virtualized real address and the real address. Therefore, in the virtual computer system, 2
There was a kind of address translation table. Virtual address → virtual real address (real address) Virtual real address → real address (absolute address) Hereinafter, a virtualized real address is simply called a real address, and a real address corresponding to a real real memory is called an absolute address. However, it is a great overhead to perform these two types of address translations each time there is a memory access, and there is a cost / performance problem in including these two address translation mechanisms in hardware. A proposed solution to this problem is the shadow page table. This shadow page table is a direct management table of the virtual address and the absolute address described above. However, this shadow page table must be reflected in the shadow page table if the correspondence between the above-mentioned two address conversion tables is changed, and the reflection is performed by the virtual machine monitor. Though less expensive than the shadow table method, there was still a large overhead.

(2) Another realization method is a method using an address F register and an address L register. The address F register holds the start address of the absolute address of the real space possessed by each virtual machine and sets the address L
The register holds the final address. The virtual machine operates within the range of the address F register and the address L register. The operation is such that the operating system operating on the virtual machine actually addresses the virtual real address using the address conversion table is the DAT on the real machine.
It is the same as using the mechanism to translate addresses. After that, the contents of the address F register are added to this real address by hardware, and it is checked whether the value of the address L register is exceeded. As a result, the real memory is accessed at the address. With this method, the space having the same address on the real address is expanded.

[0005]

The above-mentioned conventional address conversion method (1) has a problem that the amount of overhead / hardware investment is large. Also, (2)
In the method, since the real memory is divided in advance and allocated to the virtual machine, there is a problem that it is impossible to share the memory between the VMs during the operation.

[0006]

A control method for a virtual computer system according to the present invention comprises a plurality of operating systems and a management program for managing the plurality of operating systems. In a virtual computer system in which a plurality of operating systems are made to operate on one computer system, a plurality of continuous spaces on a main storage device are allocated to each of the plurality of operating systems and managed. Has an address management table,
In addition, the virtual address real address conversion means for converting a virtual address to a real address by the address conversion table in the operating system, and the real address obtained by this virtual address real address conversion means are made to correspond to the addresses of the main memory by the address management table. It is provided with a real address / absolute address conversion means.

A virtual computer system control method according to another invention of the present invention is the above-mentioned one, in which the address management table is changed by changing the address management table to change the real memory allocated to each operating system. Means, notifying means for notifying the real memory changed by the address management table changing means by the operating system, and the operating system notified by the notifying means changes the memory based on the notified contents. It is provided with a memory changing means.

A control method for a virtual computer system according to still another aspect of the present invention is the first aspect of the present invention, which checks the usage status of the real memory of the operating system managed by the management program at regular intervals. It has a judgment means that can judge the movement of memory between OSs,
Further, when it is necessary to move the address management table, the address management table is changed by changing the address management table, and the real memory changed by the address management table changing means The system is provided with notifying means for notifying by the system, and memory changing execution means for making the memory change based on the notified contents of the operating system notified by the notifying means.

[0009]

According to the present invention, the memory allocated to each virtual computer is divided, and the divided memory units are accommodated.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the block diagram shown in FIG. 1, a plurality of virtual computers (hereinafter abbreviated as VM) V are provided in one computer system.
There is a management program (hereinafter, referred to as a virtual machine monitor) that simulates M1 and VM2 and manages this virtual machine. In FIG. 1, 1-1 is a virtual computer monitor that manages a virtual computer, 1-2-1, 1-2-2 are address conversion tables, 1-3-1 and 1-3-2 are operating systems. An address management table for allocating a plurality of contiguous spaces on the main memory to each system and managing the same, 1-4 are virtual addresses for converting from virtual addresses to real addresses by an address conversion table in the operating system. Real address translation means,
1-5 is an address management table 1-the real address obtained by the virtual address real address converting means 1-4.
It is a real address absolute address conversion means for associating with a main memory address by 3-1 and 1-3-2.

1-6 is an address management table 1-3.
Address management table changing means for changing the actual memory allocated to each operating system by changing 1, 1-3-2, 1-7-1 and 1-7-2 are the address management table changing means 1 OS notification means for notifying the real memory changed by -6 by the operating system, and 1-8-1, 1-8-2 are address conversion table rewriting means, which are the address conversion table rewriting means 1-8-1, 1 -8-2 is OS notification means 1-7-
The operating system notified by 1, 1-7-2 constitutes a memory change execution means for changing the memory based on the notified contents. Reference numeral 1-9 is a memory usage status check unit, and this memory usage status check unit 1-9 checks the usage status of the actual memory of the operating system managed by the management program at regular intervals and moves the memory between OSs. It constitutes a judgment means that can judge.

When a move is required, the address management tables 12-1 and 12-2 are changed to change the real memory allocated to each operating system. , OS notifying means 1-7-1, 1-7-2 for notifying the real memory changed by the address management table changing means 1-6 by the operating system, and the OS notifying means 1-7-1, 1- The operating system notified by 7-2 is provided with memory change execution means (address conversion table rewriting means 1-8-1, 1-8-2) for changing memory based on the notified contents. ..

FIG. 2 is an explanatory diagram showing the details of the address management tables 1-3-1 and 1-3-2 in FIG.
Shows a VM1 address management table,
(B) shows a VM2 address management table.

FIGS. 3 and 4 are explanatory diagrams in which specific numerical values are given to the block diagram of the embodiment shown in FIG. 1, (a) of FIG. 4 shows a VM1 management table, and (b) of FIG. The management table for VM2 is shown.

FIG. 5 is a block diagram showing a configuration example of the real address / absolute address converting means 1-5 in FIG. In FIG. 5, 5-1 is an A address, 5-2 is an address table register, 5-3 is management for VM1 and 5-4 is output of A address 5-1 and output of VM1 management 5-3. The comparator 5-5 is the comparator 5-
It is the B address which is the output of 4.

6 to 9 are explanatory views of the memory movement between VMs according to the present invention. FIGS. 6 and 7 show a state before the movement, FIG. 9 shows a state after the movement, and FIG. 8 shows a processing flowchart thereof. It is a thing. In FIG. 7, (a) is V
The management table of M1 is shown, (b) is the management table of VM2, (c)
Indicates a VM3 management table. In FIG. 9, (a) shows the state after movement, (b) is the management table of VM1, and (c) is the VM.
2 shows a management table of 2, and (d) shows a management table of VM3.

FIG. 10 is an automatic VM for explaining the operation of FIG.
It is a flow chart which shows inter-memory movement processing.

The operation of the embodiment shown in FIG. 1 will be described below with reference to FIGS. First, the real memory allocated to the VM is divided into a plurality of parts and allocated. The VM 1 uses the addresses (hereinafter, referred to as absolute addresses) c1 to c2 that represent the memory resources on the real computer as real addresses (hereinafter, simply referred to as real addresses) on the virtual computer.
The virtual real addresses a1 to a2 are allocated to the systemized addresses c3 to C4 continuous areas in association with 10 to a1. On the other hand, the VM2 associates the absolute addresses c2 to c3 with the VM20 to b1 as virtual real addresses, and allocates the real addresses b1 to b2 by dividing them into the systematized addresses c4 to C5 continuous areas. The absolute address and real address of each VM are managed by the address management tables 1-3-1, 1-3-2 in the virtual machine monitor 1-1. This address management table exists for each virtual computer.

FIG. 2 shows a concrete example of the address management tables 1-3-1 and 1-3-2 as shown in FIG. The virtual real space of each virtual machine (the space specified by the real address) is the systemized space (the space indicated by the absolute address)
There are as many virtual real spaces and systemized space correspondence tables as the number indicating how many are divided.
The present invention is characterized in that the virtual real space of one virtual computer is assigned to a plurality of continuous systematized spaces. The address management table is a table for managing the divided systemized space. The division information of this address management table is given and determined as the initial value of the virtual computer. Further, it is only a management table of real addresses and absolute addresses, and is different from the correspondence table of virtual addresses and absolute addresses such as the shadow page table.

Therefore, it is not a management table such as the shadow page table which needs to be changed frequently.
The virtual computer address management table shown in FIG.
As shown in, the virtual real address 0 and the systemized address C1 correspond to each other in the address management table of the VM1, and the size thereof is set as the size 1. Further, the virtual real address a1 and the systemized address C3 correspond to each other, and their size is set as size 2.

Similarly, the address management table of the VM2 is also set. This address management table is an example, and any other format may be used as long as it is a table in which correspondence between systemized addresses and virtual real addresses can be obtained. For example, instead of the size, the systematized address and the end address of the virtual real address may be entered in the management table, or the division unit of the systematized space may be fixed and the size field may not be provided. In short, a management table that can manage multiple correspondences between the virtual real space and the system address space of each virtual machine can be used, and the management table can be easily used by an inexpensive address translation mechanism by hardware described later. It is all right.

Although the virtual computer system varies depending on the method of implementing the virtual computer system, there are generally two modes as CPU operation modes. (1) A mode in which a program on a virtual computer operates (hereinafter, abbreviated as VMOS mode) (2) A mode when a virtual computer operates (hereinafter, VM)
In a few cases, the VMM mode and the VMOS mode have realized a virtual computer system in which the privileged instruction executable mode and the non-privileged instruction mode are directly applied, and the CPU operation mode is specially set. Some computers have been newly established to realize a virtual computer system.

Next, with reference to FIGS. 3 and 4, an address conversion method implemented in the present invention will be described. Address translation works only in VMOS mode. FIG. 3 is a diagram in which specific numerical values are entered according to the conceptual diagram shown in FIG. The address management table is as shown in FIG. 4, and the size of each continuous address space is set to a value equivalent to the memory unit of the computer system in which the virtual computer system is mounted. Here, it is set to 16 MB. Here, the memory unit is a memory unit that can be embedded / separated by an operating system (hereinafter abbreviated as OS). When explaining memory interchange between virtual machines, which will be described later, the memory unit is used as a unit of division because it often operates in conjunction with OS memory incorporation / separation.

The real address space of this calculation is a space represented by 28 bits. Therefore real address 2
The maximum mountable amount represented by 8 bits is 256 MB. Further, in this example, the continuous space allocated to the VM is fixed to 16 MB for convenience. Therefore, when a virtual computer having a real address and an absolute address as shown in FIG. 3 is associated, the address management table shown in FIG. 4 is provided for VM1 and VM2. And V
In the address management table of M1, the realized address 0 corresponds to the systemized address 1. In the case of this system, since the memory division unit is determined to be 16 MB, 1 indicates that 16000000 corresponds to the real address 0 of VM1. Similarly, in the next entry, the real address 1 indicates the address 16000000 and the absolute address 3 indicates the address 48000000.

FIG. 5 shows the hardware operation of the program on the VM 1 in this case. The address table register 5-2 in FIG. 5 is a register for notifying the HW of the address management table. The address generated by the program on the virtual computer, which is a unit of 16 MB, is the address A-1, and the first 4 bits of the address are the address management table indicated by the address table register 5-2. INDEX). In this example, since the first 4 bits of the address are "1", the systemized address is "3" when indexed. The systemized address is created by synthesizing the lower 24 bits and 3 of the A address 5-1. The result is the B address 5-5. The B address 5-5 approaches the memory. Here, of course, the B address 5-5 is the target of the cache (CASH) service.

FIG. 6, FIG. 7, and FIG. 8 are examples of memory circulation between VMs. FIG. 6 shows three VMs, that is, VM1 and V.
There are M2 and VM3. In the VM1, virtual real addresses 0 to d1 correspond to systemized real addresses g1 to g2, and virtual real addresses 0 to d2 correspond to systemized real addresses g3 to g4. In VM2, virtual real addresses 0 to e1 correspond to systemized real addresses g2 to g3, and virtual real addresses 0 to d2 correspond to systemized real addresses g4 to g5. VM
3 is virtual real address 0 to f1 is systemized real address g
5 to g6, virtual real addresses 0 to f2 correspond to systemized real addresses g6 to g7. Therefore, the address management table is as shown in FIG.

FIG. 8 is a processing flowchart of an example of exchanging memory between VMs. First, in step 101, the processing of the VM 2 is stopped. Therefore, the VM2 address management table is deleted (step 102). In the systemized address space, g2 to g3 and g4 to g5 are free areas. In step 103, the address management tables g2 to g3 are added to the VM1 address management table. Step 10
In step 4, the OS on VM1 is notified that the real memory has been added. In step 105, g4 to VM1 address management table
Add g5 address management table. In step 106, the OS on the VM 3 is notified that the real memory has been added.

The VM stop processing in step 101 is generally executed by an operator command.
Generally, the additional change of the address change management table in step 103 is generally changed by a command, but in some cases, when VM2 is stopped, VM1, VM1 is automatically changed.
In some cases, it is incorporated into VM3. To notify the OS from each VM to step 104, after executing step 103,
In some cases, it is executed by an OS command, and in some cases, after the processing of step 103 is executed, the VM monitor automatically notifies. Further, since steps 102 to 103 are both executed by commands, commands executed by both at the same time may be supported.

As a result, the systemized address becomes the mapping shown in FIG. 9, and the memory possessed by VM2 can be allocated to VM1 and VM3. In addition, effective use of the memory can be automatically performed by automatically performing this embedding processing.

An example thereof is shown in FIG. In step 201 in FIG. 10, VM1 and VM are displayed on the virtual machine monitor.
Inquires about the actual memory usage status in 2. The inquiry process is performed by the VM monitor notifying the VM of an interrupt. In this case, a special interrupt code indicating the cause is notified. Steps 202 and 2
Reference numeral 03 is an OS that has executed the inquiry status of the real memory and checks the usage status of the real memory. This real memory usage is typically collected for the operating system to improve memory usage. In some cases, the number of times overload control is performed is notified. In short, it only needs to be able to check if the operating system is out of memory and inefficient. After that, the result is notified by means of communication from the operating system on the VM to the VM monitor called a handshake.

In steps 204 and 205, VM1 and VM
Check the memory usage status of 2. Also, check the status to see if there is a change in memory movement. This check method is performed by comparing the statuses of the VMs. And VM
If it is necessary to move the memory from 1 to VM2, the VM and the operating system are instructed to perform the memory disconnection in the same manner as in step 206 and the memory disconnection instruction step 201.
The memory of M is separated, and the completion notification is executed by the VM monitor. In addition, the VM memory installation instruction is given in step 2.
09, 210, 211.

[0032]

As described above, according to the present invention, since the memory allocated to the virtual machine is divided and the divided memory units are accommodated, the overhead amount / hardware investment amount is small, and This has the effect that memory can be exchanged between VMs.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing details of an address management table in FIG.

3 is an explanatory diagram in which specific numerical values are given to the block diagram of the embodiment shown in FIG.

FIG. 4 is an explanatory diagram in which specific numerical values are given to the block diagram of the embodiment shown in FIG.

5 is a block diagram showing a configuration example of real address / absolute address conversion means in FIG. 1. FIG.

FIG. 6 is an explanatory diagram showing a state before movement, which is used for explaining memory movement between VMs according to the present invention.

FIG. 7 is an explanatory diagram showing a state before movement, which is used for explaining memory movement between VMs according to the present invention.

FIG. 8 is a flowchart showing a process for explaining memory movement between VMs according to the present invention.

FIG. 9 is an explanatory diagram showing a state after movement, which is used for explaining memory movement between VMs in the present invention.

FIG. 10 is a flowchart showing an automatic VM-to-VM memory movement process for explaining the operation of FIG. 1;

[Explanation of symbols]

1-1 Virtual machine monitor 1-2-1, 1-2-2 Address conversion table 1-3-1, 1-3-2 Address management table 1-4 Virtual address real address conversion means 1-5 Real address absolute address Converting means 1-6 Address management table changing means 1-7-1, 1-7-2 OS notifying means 1-8-1, 1-8-2 Address conversion table rewriting means 1-9 Memory usage status check unit

Claims (3)

[Claims] 1. A plurality of operating systems and a management program for managing the plurality of operating systems are provided, and the plurality of operating systems are operated on one computer system under the control of the management program. In the virtual computer system described above, a plurality of continuous spaces in the main memory are allocated to each of the plurality of operating systems, and an address management table for managing the spaces is provided, and an address conversion table in the operating system is used. Virtual address real address conversion means for converting a virtual address to a real address, and real address absolute address conversion for associating the real address obtained by the virtual address real address conversion means with the address of the main memory by the address management table. A control method for a virtual computer system, characterized by comprising means. 2. The virtual computer system control method according to claim 1, wherein an address management table changing means for changing the real memory allocated to each operating system by changing the address management table, and the address management table. The operating system notified by the operating system notifies the real memory changed by the changing unit, and the memory change execution unit for executing the memory change based on the notified contents. A control method for a virtual computer system characterized by: 3. The virtual computer system control method according to claim 1, wherein the management program checks the usage status of the real memory of the operating system managed by the management program at regular intervals to determine whether to move the memory between the OSs. And an address management table changing means for changing the real memory allocated to each operating system by changing the address management table when there is a need to move the address management table and the address management table changing means. The present invention is characterized by comprising notifying means for notifying the real memory by the operating system, and memory changing execution means for making the memory change on the basis of the notified contents of the operating system notified by the notifying means. Control method of virtual computer system.