JP5471677B2 - Virtual disk control system, method and program - Google Patents

Description

  The present invention relates to a virtual disk control system, a virtual disk control method, and a virtual disk control unit that control a virtual disk of a virtual machine.

  As the amount of memory installed in a server apparatus increases dramatically, active use of memory in a virtual environment in which a virtual machine is built on the server apparatus is required.

  For example, as a related technique, Patent Literature 1 describes a system that redistributes memory according to load fluctuations of each virtual machine built on a server device.

JP-A-6-110715

  In a virtual environment, depending on the guest OS operating on the constructed virtual machine, there may be a limit on the amount of memory that can be used. In this case, even if the physical machine has a large-capacity physical memory, the physical memory cannot be used effectively.

  For example, in the system described in Patent Document 1, it is not assumed that the amount of memory that can be used is limited as described above. In such a case, physical memory is effectively used. I can't.

  Accordingly, an object of the present invention is to provide a virtual disk control system, a virtual disk control method, and a virtual disk control unit that can effectively use physical memory in a virtual environment regardless of the guest OS.

  The virtual disk control system according to the present invention is a storage destination that designates a physical storage destination of data in a physical memory mounted on the physical machine when a virtual machine operating on the physical machine stores predetermined data in the virtual disk. Based on the designation by the designation means and the storage destination designation means, the data is stored in the physical memory, the storage area information indicating the virtual storage area in the virtual disk, and the storage location information indicating the actual storage location in the physical memory. And associating means for associating with each other.

  According to the virtual disk control method of the present invention, when a virtual machine operating on a physical machine stores predetermined data in the virtual disk, the physical storage destination of the data is specified in the physical memory mounted on the physical machine. The data is stored in the physical memory based on the above, and the storage area information indicating the virtual storage area in the virtual disk is associated with the storage location information indicating the actual storage location in the physical memory.

  The virtual disk control means according to the present invention specifies a physical storage destination of data in a physical memory mounted on the physical machine when the virtual machine operating on the physical machine stores predetermined data in the virtual disk. Corresponding storage location specifying process to store data in physical memory based on the specification and to associate storage area information indicating a virtual storage area in the virtual disk with storage location information indicating an actual storage location in the physical memory And processing.

  According to the present invention, physical memory can be effectively used in a virtual environment regardless of the guest OS.

It is a block diagram which shows the structural example of the virtualization system to which the virtualization disk control method by this invention is applied. It is a block diagram which shows the operation example of a virtual disk control system. It is a flowchart which shows the process example at the time of the data storage which a virtual disk control system performs. It is a flowchart which shows the process example at the time of the data access which a virtual disk control system performs. It is a block diagram which shows the minimum structural example of a virtual disk control system.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of a virtualization system to which a virtualization disk control method according to the present invention is applied. As shown in FIG. 1, in this embodiment, the virtualization system includes a physical machine 3, and the virtual machine 1 is constructed using the virtualization software 2 on the physical machine 3. In the present embodiment, the virtualization system constructs one virtual machine, but a plurality of virtual machines may be constructed. Further, specifically, the physical machine 3 stores the virtualization software 2 shown in FIG. 1 in the storage unit.

  Specifically, the physical machine 3 is realized by an information processing apparatus such as a personal computer that operates according to a program. The physical machine 3 includes a physical memory 31 and a physical disk device 32.

  The physical memory 31 stores data 311 corresponding to a paging file generated by the virtual machine 1 according to the guest OS. In the present embodiment, the guest OS refers to an OS operating on the virtual machine 1.

  Specifically, the physical disk device 32 is realized by a storage device such as an optical disk device or a magnetic disk device, and stores a virtual disk file 321 that is the substance of the virtual disk 11.

  As shown in FIG. 1, in a general virtualization system, the substance of the paging file 111 generated by the virtual machine 1 is stored in the virtual disk file 321 as a paging file 3211. On the other hand, in the present embodiment, as described above, the data 311 corresponding to the paging file that is the substance of the paging file 111 generated by the virtual machine 1 is stored in the physical memory 31.

  Specifically, the virtual machine 1 is realized by the CPU of the physical machine 3 executing processing according to the virtual software 2. As shown in FIG. 1, the virtual machine 1 includes a virtual disk 11 and virtual disk control means 12.

  The virtual disk 11 stores a paging file 111 generated by the virtual machine 1 in addition to the data stored in the virtual machine 1. Specifically, the virtual disk 11 is realized by the physical disk device 32 and the physical memory 31 of the physical machine 3. In principle, data stored in the virtual disk 11 is stored as a virtual disk file 321 in the physical disk device 32 of the physical machine 3.

  The virtual disk control unit 12 operates in the guest OS of the virtual machine 1, and is specifically realized by the CPU of the physical machine 3 executing processing according to the virtual software 2 and the guest OS. The virtual disk control means 12 has a function of controlling the storage location of the substance of data stored in the virtual disk 11.

  As shown in FIG. 1, the virtualization system to which the virtualization disk control method is applied includes virtual disk processing means 21. Specifically, the virtual disk processing unit 21 is realized by the CPU of the physical machine 3 executing the process according to the virtual software 2. The virtual disk processing means 21 has a function of managing the area of the virtual disk 11 and the data storage location in association with each other. Further, the virtual disk processing unit 21 has a function of updating the allocation table 211 used for controlling the virtual disk 11 stored in the allocation table storage unit (not shown). The virtual disk processing means 21 has a function of controlling access to data from the virtual disk 11.

  Specifically, the allocation table storage means is realized by the physical memory 31. Details of the allocation table 211 stored by the allocation table storage means will be described later.

  In the present embodiment, the virtual disk entity is described as a file stored in the physical disk. However, the present invention is not limited to the file format, and data as the virtual disk entity may be directly stored in the physical disk. In addition, the virtual disk file is generated, the data storage area in the virtual disk is determined and then the area is notified, and the data storage area in the virtual disk is determined, and then the area is notified. A virtual disk file may be generated. When the virtualization system constructs a plurality of virtual machines, each virtual machine may be provided with a virtual disk control unit 12 or controlled by a single virtual disk control unit 12. Also good.

  Next, the operation of the virtual disk control system will be described with reference to FIGS. FIG. 2 is a block diagram illustrating an operation example of the virtual disk control system. FIG. 3 is a flowchart showing an example of processing at the time of data storage executed by the virtual disk control system.

  First, an operation when the virtual machine 1 stores data will be described. A virtual machine 1 constructed in the virtualization system shown in FIG. 1 has an OS (guest OS) therein. When the virtual machine 1 generates the paging file 111 according to the OS, the virtual machine 1 stores the generated paging file 111 in the virtual disk 11.

  Here, in the present embodiment, when the virtual machine 1 generates the paging file 111 (step S11 in FIG. 3), the virtual disk control unit 12 specifies a storage area in the virtual disk 11 of the generated paging file 111 (FIG. 3). 3 step S12). For example, the virtual disk control unit 12 operates in cooperation with a guest OS disk control program (driver) in order to specify a storage area.

  Next, the virtual disk control unit 12 outputs, to the virtual disk processing unit 21, an instruction to set the physical storage location of the substance of the paging file 111 together with information (for example, an address) indicating the specified storage area (FIG. 3). Step S13). Note that the virtual disk control unit 12 may determine whether to change the storage destination to the physical memory 31 according to a predetermined rule instead of changing the storage destination to the physical memory 31 without fail. For example, the virtual disk control unit 12 may change the storage destination to the physical memory 31 only for data that requires high-speed access or data that is frequently used.

  Next, the virtual disk processing means 21 secures a predetermined area in the physical memory 31 based on the output instruction, and stores the substance of the paging file 111 (step S14 in FIG. 3).

  Next, the virtual disk processing means 21 allocates the identified virtual disk 11 area to the reserved physical memory 31 area. Specifically, the virtual disk processing means 21 determines information indicating the storage area of the paging file 111 in the virtual disk 11 and information indicating the storage location of the paging file 111 (specifically, based on the information output together with the instruction). Updates the allocation table 211 so as to store them in association with each other (step S15 in FIG. 3).

  Thereafter, when an access request designating the area allocated in step S15 is output, the virtual disk processing means 21 performs control so that data stored in the physical memory 31 is referred to / written. The allocation table 211 holds information indicating the area of the virtual disk 11 and information indicating the storage location of the area in association with each other. In the allocation table 211 in the initial state, the area of the virtual disk 11 is associated with the virtual disk file 321. That is, data stored in the virtual disk 11 is stored as a virtual disk file 321 in the physical disk device 32 of the physical machine 3 in principle.

  In the general virtualization system shown in FIG. 1, the substance of the paging file 111 is stored in the physical disk device 32 as the paging file 321 of the guest OS included in the virtual disk file 321. On the other hand, in this embodiment, as shown in FIG. 2, the substance of the paging file 111 is not stored in the physical disk device 32, but the data 311 corresponding to the paging file of the guest OS is stored in the physical memory 31.

  Next, an operation for accessing stored data will be described with reference to FIGS. FIG. 4 is a flowchart showing an example of processing at the time of data access executed by the virtual disk control system.

  When accessing the data stored in the virtual disk 11, the virtual machine 1 specifies the storage area of the target data in the virtual disk 11 (step S21). In the present embodiment, it is assumed that the virtual machine 1 accesses the paging file 111.

  Next, the virtual machine 1 outputs an access request to the target data to the virtual disk processing unit 21 together with information indicating the storage area in the identified virtual disk 11 (step S22).

  Next, the virtual disk processing means 21 refers to the allocation table 211 based on the output information indicating the storage area in the virtual disk 11 and determines whether or not the corresponding area is allocated to the physical memory 31 (step). S23).

  If it is determined in step S23 that the disk is allocated, the virtual disk processing unit 21 performs control to access the target data stored in the physical memory 31 based on the information indicating the storage area in the virtual disk 11 and the allocation table 211. It performs (step S24). In this embodiment, the virtual disk processing unit 21 performs control to access data 311 corresponding to the paging file of the guest OS stored in the physical memory 31.

  If the virtual disk processing unit 21 determines that the virtual disk 11 is not allocated, the virtual disk processing unit 21 accesses the virtual disk file 321 of the physical disk device 32 based on the information indicating the storage area in the virtual disk 11 and the allocation table 211. Control is performed (step S25).

  In this embodiment, the example in which the paging file generated by the virtual machine 1 is stored in the physical memory 3 has been described. For example, a temporary file generated by the guest OS or an application running on the guest OS is stored in the physical memory 3. You may control to store. By doing so, it is possible to generate a temporary file that can be accessed at high speed without consuming the memory of the guest OS.

  From the above, it can be said that the present embodiment includes means for solving the following problems.

  A general OS is provided with a virtual memory mechanism, and a virtualized memory entity is stored in a paging file existing on a disk. On the other hand, when a guest OS operating in a virtual machine realized by a virtualization mechanism (hereinafter referred to as a host) creates a paging file, the entity is placed in a storage existing on the host.

  On the other hand, this embodiment implements a mechanism that allows the guest OS to specify a memory as a location for storing a specific area of the virtual disk. By doing so, the guest OS can designate a paging file area and place it on the memory on the host, thereby enabling high-speed access.

  In FIG. 1, the virtual machine 1 is realized by virtualization software 2. The virtual machine 1 has a virtual disk 11 in which a guest OS paging file 111 is stored. The entity of the virtual disk 11 usually exists as a virtual disk file 321 in the physical disk device 32 in the physical machine 3 in which the virtualization software 2 is running. Therefore, the substance of the paging file 111 in the virtual disk 11 exists as a paging file 3211 in the virtual disk file 321.

  In this embodiment, the virtual disk control unit 12 operating in the virtual machine 1 is used to notify the virtual disk processing unit 21 of the location of the paging file 111 in the virtual disk 11. As a result, the substance of the paging file that is generally created in the virtual disk file 321 can be created in the physical memory 341 of the physical machine 3.

  From the above, this embodiment can provide the following effects.

  For example, in the case where an old OS or the like is moved on a virtual machine, it is assumed that the memory that can be used by the OS is limited. Even in such a case, in this embodiment, a high-speed access means can be provided by arranging a paging file or the like on the host memory, and the operation of the guest OS can be made efficient. Further, the memory of the host can be effectively used regardless of the type of the guest OS.

  Some applications hold information such as passwords on a memory. In this case, when the information is swapped out, the information remains in the paging file, and there is a risk of leakage. However, in this embodiment, since the information is held in the physical memory, it disappears at the time of shutdown, and the risk can be avoided. This can be said to be more efficient than executing the process of deleting the swap file at each shutdown.

  Further, in this embodiment, data that does not need to be permanently retained is not created in the virtual disk file, so that the storage usage can be reduced.

  As described above, in this embodiment, in the virtual machine, the storage location of the entity of the virtual disk used by the guest OS can be managed by the control program in the guest OS.

  In addition, the virtual disk control system in the present embodiment differs from existing technologies in the following points.

  Usually, the cache is a subset of data existing in the physical disk device. Even if all data is included in the cache, the relationship between the two always holds. However, in this embodiment, it is possible to cut the relationship between the two. Similarly, a mechanism called MemoryMapped I / O is known, but since it is a method of mapping a file on a storage to a memory, it cannot be used as a means for solving the above problem.

  In this embodiment, the virtual disk data existing on the physical memory is not constructed on the RAM disk existing on the memory, but exists in the memory space directly managed by the virtualization software. When a virtual disk is created on a host RAM disk, an unnecessary area is stored in the RAM disk. Therefore, it can be said that the virtual disk control system according to the present embodiment is more efficient in using the memory. .

  From the viewpoint of speed, it can be said that the guest paging file dedicated drive is provided on the host RAM disk. However, since the virtual disk control system according to the present embodiment can be implemented without providing a RAM disk area, the use of the memory is efficient and the application range is wide.

  The method of caching virtual disk files on the host seems to have a similar effect, but the cache cannot specify an area. In the cache, there is always a one-to-one relationship with the data on the virtual disk. However, in the virtual disk control system according to the present embodiment, this relationship does not always hold. Also, if there is a large amount of data that can only be called once, the effect will be different. Further, in the virtual disk control system according to the present embodiment, the guest OS (virtual machine) itself can control it.

  Next, the minimum configuration of the virtual disk control system according to the present invention will be described. FIG. 5 is a block diagram showing a minimum configuration example of the virtual disk control system. As shown in FIG. 5, the virtual disk control system includes a storage destination designation unit 101 and an association unit 201.

  In the virtual disk control system with the minimum configuration shown in FIG. 5, the storage destination designating unit 101 sets the physical storage destination of data when the virtual machine operating on the physical machine stores predetermined data on the virtual disk. Specify the physical memory installed on the machine. The association unit 201 stores the data in the physical memory based on the designation of the storage destination designation unit 101, and also shows the storage area information indicating the virtual storage area in the virtual disk and the actual storage location in the physical memory. Corresponding storage location information.

  Therefore, according to the minimum configuration virtual disk control system, it is possible to effectively use physical memory in a virtual environment regardless of the guest OS.

  In this embodiment, the characteristic configuration of the virtual disk control system as shown in the following (1) to (5) is shown.

  (1) In the virtual disk control system, a virtual machine (for example, realized by the virtual machine 1) operating on a physical machine (for example, realized by the physical machine 3) transfers predetermined data to a virtual disk (for example, a virtual machine). A storage destination designating unit (e.g., virtual storage) that designates a physical storage destination of data in a physical memory (e.g., realized by the physical memory 31) mounted on the physical machine. And the storage area information (for example, address information) indicating the virtual storage area in the virtual disk, and the physical Corresponds to storage location information (for example, physical memory address information) indicating the actual storage location in memory Correlating means (e.g., as implemented by the virtual disk processor 21), characterized in that it comprises a.

  (2) In the virtual disk control system, the association unit stores allocation information (for example, realized by the allocation table 211) including the storage area information and the storage location information in association with each other (for example, the allocation table storage unit) The virtual disk control system stores access control means (for example, virtual disk processing means 21) for controlling access based on data storage area information and allocation information when a virtual machine accesses predetermined data. May be further included.

  (3) In the virtual disk control system, the access control means, when the virtual machine accesses predetermined data, if the storage area information of the data is not associated with the storage location information in the allocation information, The physical disk device mounted on the machine may be controlled so as to be accessed (for example, the virtual disk file 321 of the physical disk device 32 is accessed).

  (4) In the virtual disk control system, the storage destination specifying unit specifies a virtual storage area in the virtual disk when the virtual machine stores predetermined data in the virtual disk, and the association unit is the storage destination specifying unit. May be configured to store allocation information including storage area information indicating the storage area specified by and storage location information in association with each other.

  (5) In the virtual disk control system, when the virtual machine generates a paging file (for example, the paging file 111), the storage destination specifying unit is configured to specify the physical storage destination of the generated paging file in physical memory. May be.

  The present invention can be applied to a use for controlling a virtual environment.

DESCRIPTION OF SYMBOLS 1 Virtual machine 2 Virtualization software 3 Physical machine 11 Virtual disk 12 Virtual disk control means 21 Virtual disk processing means 31 Physical memory 32 Physical disk unit 101 Storage destination designation means 111 Paging file 201 Correlation means 211 Assignment table 311 Guest OS paging Data equivalent to file 321 Virtual disk file 3211 Guest OS paging file

Claims (9)

When a virtual machine operating on a physical machine stores predetermined data in a virtual disk, a storage destination designating unit for designating a physical storage destination of the data in a physical memory mounted on the physical machine;
Based on the designation of the storage destination designating means, the data is stored in the physical memory, storage area information indicating a virtual storage area in the virtual disk, and storage location information indicating an actual storage location in the physical memory; A virtual disk control system comprising: an association means for associating each other. The association means stores allocation information including the storage area information and the storage location information in association with each other,
The virtual disk control system according to claim 1, further comprising access control means for controlling access based on the storage area information of the data and the allocation information when the virtual machine accesses predetermined data. When the virtual machine accesses predetermined data, and the storage area information of the data is not associated with the storage location information in the allocation information, the access control means is provided for the physical disk device mounted on the physical machine. The virtual disk control system according to claim 2, wherein the virtual disk control system is controlled to access. The storage destination designating means specifies a virtual storage area in the virtual disk when the virtual machine stores predetermined data in the virtual disk,
The associating unit stores allocation information including the storage area information indicating the storage area specified by the storage destination designating unit and the storage location information in association with each other. The virtual disk control system described. 5. The virtual storage device according to claim 1, wherein when the virtual machine generates a paging file, the storage destination specifying unit specifies a physical storage destination of the generated paging file in a physical memory. Disk control system. When a virtual machine operating on a physical machine stores predetermined data in a virtual disk, the physical storage destination of the data is designated as physical memory mounted on the physical machine,
The data is stored in the physical memory based on designation, and storage area information indicating a virtual storage area in the virtual disk is associated with storage location information indicating an actual storage location in the physical memory. Virtual disk control method. Storing allocation information including storage area information and storage location information in association with each other;
The virtual disk control method according to claim 6, wherein when the virtual machine accesses predetermined data, the access is controlled based on the storage area information of the data and the allocation information. On the computer,
When a virtual machine operating on a physical machine stores predetermined data in a virtual disk, a storage destination specifying process for specifying a physical storage destination of the data in a physical memory mounted on the physical machine;
An association process for storing the data in the physical memory based on designation and associating storage area information indicating a virtual storage area in the virtual disk with storage location information indicating an actual storage location in the physical memory Virtual disk control program to be executed. On the computer,
In the associating process, the process of storing the allocation information including the storage area information and the storage location information in association with each other is executed.
The virtual disk control program according to claim 8, wherein when a virtual machine accesses predetermined data, an access control process for controlling access is executed based on the storage area information of the data and the allocation information.

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