JP2000330949A - Method and device for paging control over virtual storage system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the paging control over the virtual storage system which appears to have the same effect with memory extension without extending the memory of a client computer in network environment consisting of multiple computers. SOLUTION: A client computer 10 is equipped with an artificial paging device 16 as the paging destination of a real memory 14 and a artificial paging device driver 18 which performs the process of the artificial paging device 16. A server computer 20, on the other hand, is equipped with a paging service demon process 20A, which receives an I/O request issued by the artificial paging device driver 18 corresponding to a page-in/page-out process, in a virtual memory 22. Consequently, the page-in/page-out process is performed by using the virtual memory 22 of the server computer 20 without extending the memory of the client computer 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling paging of a virtual storage system, and more particularly, to a PC and a WWW.
The present invention relates to a virtual storage system which is applied in a network environment including a plurality of computers such as a server and a server and can suppress an increase in internal memory on a client computer side.

[0002]

2. Description of the Related Art In a recent network environment, PCs and W
Instead of connecting a large number of disk devices for each client such as S, a large number of disk devices are connected to the file server computer, and various file information is stored therein. The file information on the disk of the file server computer can be used. However, the same cannot be performed for the internal memory, and the memory has to be increased as necessary for each client such as a PC and a WS.

[0003]

Therefore, in the conventional technique, it is necessary to add an internal memory for each client computer, and the work of adding the internal memory is difficult. Further, the internal memories of all the client computers are not always used, and there is a problem that increasing the memory individually is inefficient / high in cost. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems in the related art. A virtual computer system capable of eliminating the increase in the internal memory on the client side only by increasing the internal memory on the server computer side. It is an object to provide a paging control method and apparatus.

[0004]

In order to achieve the above object, a method and apparatus for controlling paging of a virtual storage system according to the present invention provide a virtual computer system having a memory management device, in which a plurality of computer systems have a pseudo memory which is a paging destination of a real memory. A first computer system having a paging device, a pseudo paging device driver for executing the processing of the pseudo paging device, and receiving an I / O request issued by the pseudo paging device driver in response to page-in / page-out. A second computer system having a paging service daemon process, wherein the paging service daemon process of the second computer system includes a page with an I / O request to page out from the pseudo-paging device driver of the first computer. Au When the data is received, the page-out data is received and stored in a virtual address space in the own system, and the paging service daemon process of the second computer system sends a page from the pseudo paging device driver of the first computer. Inn I /
When receiving the O request, the data stored in the virtual address space in the own system is sent back to the first computer system as page-in data.

Further, in the paging control method for a virtual storage system according to the present invention, a plurality of the paging service daemon processes are provided in the second computer system, and the I / O request from the pseudo paging device driver of the first computer system is provided. / O requests are shared and processed using the plurality of paging service daemon processes.

In the paging control method for a virtual storage system according to the present invention, the paging service daemon process is provided in a plurality of second computer systems, and the paging service daemon process is provided from the pseudo paging device driver of the first computer system. An I / O request is shared and processed using the paging service daemon process in the plurality of second computer systems.

Further, the paging control method for a virtual storage system according to the present invention is characterized in that the page-in data and the page-out data are striped and held by a plurality of the paging service daemon processes.

In the paging control method for a virtual storage system according to the present invention, the page-in data and the page-out data are stored in a virtual memory of the second computer by a plurality of paging service daemon processes.
And stored.

Further, in the paging control method for a virtual storage system according to the present invention, the page-in data and the page-out data are stored in a virtual memory of the second computer by a plurality of paging service daemon processes.
And restoring the data corresponding to the stopped process from the other page-in data or page-out data even if one of the paging service daemon processes is stopped. I do.

Therefore, according to the present invention, the paging data of the client computer (first computer) is stored in the address space managed by the paging service daemon process of the server computer (second computer), so that the server can store the paging data. If there is enough real memory in the computer, paging of the client computer can be processed at a very high speed, and an effect substantially equivalent to the increase in the real memory of the client computer can be obtained. As a result, without increasing the memory of the client computer,
The computer in the network environment can be used efficiently only by increasing the memory of the server computer if necessary.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the virtual storage system according to the present invention. A client computer (first computer) 10 and a server computer (second computer) 20 are connected via a network 30. The client computer 10 includes at least a process 10A to be executed, a virtual memory 12 forming an address space for executing the process 10A, a real memory 14, a virtual memory space, and a real memory as devices for achieving the present invention. A pseudo paging device 16 for performing a paging operation on a space, and an I / O device for performing a paging operation
A pseudo paging device driver 18 for transferring a request to the server computer 20 is provided.

On the other hand, the server computer 20 is provided with a paging service daemon process 20A for receiving an I / O request, a virtual memory 22, a real memory 24, and a paging device 26 (disk device). Next, the operation of the first embodiment of the virtual storage system according to the present invention will be described.

On the client computer 10, for example, it is assumed that the process 10A is currently running. In order to execute the process 10A, a memory space is formed as a virtual memory (virtual address space) 12, and the virtual memory 1
2 and a real memory 14 are performing a mapping operation. For example, when a page of the real memory 14 is not allocated to a page of the virtual memory 12, a page fault occurs, and necessary data is exchanged between the real memory 14 and the paging device 26 of the server computer 20, ie, a so-called page fault. Paging (page-in / page-out) operations are performed.

In the present invention, a pseudo paging device 16 is provided in the client computer 10 as the paging device. The paging operation on the pseudo paging device 16 is performed by issuing an I / O request to the pseudo paging device driver 18.

[0015] The pseudo paging device driver 18 includes:
When a page-in or page-out I / O request is received from the pseudo paging device 16, the request is transferred to the paging service daemon process 20 </ b> A running on the server computer 20 via the network 30. Paging service daemon process 20A on server computer
When an I / O request corresponding to page out is received from the pseudo paging device driver 18 of the client computer 10, the pseudo paging device 16,
Pseudo paging device driver 18, network 3
At the same time, the page-out data is also received via “0” and stored in the virtual memory 22 (virtual memory space) in the computer 20.

On the other hand, the paging service daemon process 20A on the server computer
When the I / O request corresponding to the page-in is received from the pseudo paging device driver 18 of the client computer 10, the page-in data is taken out from the virtual memory 22 in the own computer 20 and sent to the pseudo paging device driver 18 of the client computer 10. . In the client computer 10, page-in data is stored in the virtual memory 12 via the inside.

As described above, the paging data of the client computer 10 is stored in the address space managed by the paging service daemon process 20A of the server computer 20. As a result, if the server computer has sufficient real memory 24, paging of the client computer 10 can be performed at an extremely high speed. Therefore, an effect substantially equivalent to the increase of the real memory 14 of the client computer 10 can be obtained. Can be obtained.

In this case, even if the capacity of the real memory 24 mounted on the server computer 20 is not sufficient, the paging data of the client computer 10 is stored in the virtual address of the virtual memory 22 managed by the paging service daemon process 20A of the server computer 20. Since the data is stored in the space, paging is performed between the real memory 24 and the paging device 26 even if the capacity of the real memory 24 of the server computer 20 is insufficient. .

FIGS. 2 and 3 are block diagrams showing a second embodiment of the virtual storage system according to the present invention. In the second embodiment, the server computer is provided with a plurality of paging service daemon processes.

In FIG. 2, the client computer (first
Computers 41, 42, 43 and a server computer (second
Computer 45 is connected to the network 30.
Pseudo paging device drivers 410, 420, and 430 are provided in the client computers 41, 42, and 43, respectively, and a plurality of paging service daemon processes 450 and 460 are provided in the server computer 45.
The pseudo paging device driver described above is
Reference numerals 18, 16, 14, and 12 in FIG.
Also, the paging service daemon process is generically represented by reference numerals 20A, 22, 24, and 26 in FIG.
This is the same in FIGS. 4 and 6.

FIG. 3 is a diagram showing a detailed configuration of FIG. 2. The second computer 45 is provided with a plurality of paging service daemon processes 450 and 460 so as to be executable. And paging service daemon process 4
A virtual memory 451, a real memory 452, and a paging device 453 are provided corresponding to 50. The virtual memory 461, the real memory 462, and the paging device 463 correspond to the paging service daemon process 460.
Is provided. The configuration of the client computers 41, 42, and 43 is not different from the configuration of FIG.

According to the second embodiment, I / O requests from the respective pseudo paging device drivers 410, 420, 430 of the plurality of client computers 41, 42, 43 are transmitted to the plurality of paging service daemon processes of the server computer 45. Received by 450, 460,
Using the respective virtual memories 451 and 461, page-in or page-out processing can be executed in the same manner as in FIG.

Therefore, according to the second embodiment, there is an advantage that I / O requests from a plurality of client computers can be processed in parallel by a plurality of paging service daemon processes of a server computer. Further, as a means for realizing the second embodiment, if the server computer has a multi-thread function, it can be realized using the multi-thread function without placing a plurality of paging service daemon processes. Further, according to the second embodiment, there is an advantage that paging data of 4 GB or more can be processed in a 32-bit mode system.

FIGS. 4 and 5 are block diagrams showing a third embodiment of the virtual storage system according to the present invention. This third
In the embodiment, an example in which a plurality of server computers are provided is shown.

In FIG. 4, a plurality of client computers 41, 42, 43 and a plurality of server computers 50, 51
Are connected to the network 30. Pseudo paging device drivers 410, 420, and 430 are provided in the client computers 41, 42, and 43, respectively, and paging service daemon processes 500 and 510 are provided in the server computers 50 and 51, respectively.

FIG. 5 is a diagram showing the detailed configuration. Paging service daemon processes 500 and 510 are provided in the server computers 50 and 51 so as to be executable. Then, a virtual memory 501, a real memory 502, and a paging device 503 are provided corresponding to the paging service daemon process 500. Further, a virtual memory 511, a real memory 512, and a paging device 513 are provided corresponding to the paging service daemon process 510. Client computer 41,
The configurations of 42 and 43 are not different from the configuration of FIG.

According to the third embodiment, an I / O request from each of the pseudo paging device drivers 410, 420, and 430 of the plurality of client computers 41, 42, and 43 is transmitted to the paging service daemon process of the server computer 50 or 51. The page-in or page-out processing can be executed in the same manner as in FIG. 1 using the virtual memory 501 or 511 received by the virtual memory 500 or 510.

By arranging the paging service daemon process in each of a plurality of server computers, each server computer has an advantage that the real memory 502 or 512 can be effectively used. It should be noted that the above-described second embodiment and the third embodiment can be combined to provide a plurality of paging service daemon processes in a plurality of server computers.

FIG. 6 is a block diagram showing a fourth embodiment of the virtual storage system according to the present invention. In the fourth embodiment, only a client computer is used.

That is, the client computers 41, 42, 4
3 includes a pseudo paging device driver 41
0, 420, and 430, and paging service daemon processes 610, 620, and 630 are provided. And
The pseudo paging device driver 410 of the client computer 41 is connected to another client computer 42 or 43.
The paging service is received by the paging service daemon process 620 or 630.

Similarly, the pseudo paging device driver 420 of the client computer 42 receives a paging service by the paging service daemon process 610 or 630 of another client computer 41 or 43.

Further, the pseudo paging device driver 430 of the client computer 43 receives a paging service by the paging service daemon process 610 or 620 of another client computer 41 or 42. In the fourth embodiment, the same processing can be performed by a plurality of client computers.

FIG. 7 is a flowchart showing the flow of processing of the above-described pseudo paging device driver. The pseudo paging device driver receives an I / O request for paging from a process (for example, the process 10A in FIG. 1) (step S1). The pseudo paging device driver determines whether the I / O request is a READ request for page-in or a WR for page-out.
It is determined whether the request is an ITE request (step S2).

In the case of a READ request, the pseudo paging device driver sends an I / O request for page-in to a paging service daemon process of another computer (step S3). Then, page-in data processed by the paging service daemon process of another computer is received (step S4). Finally, the requester completes the request (pseudo-paging device driver)
(Step S5), and the process ends.

On the other hand, in the case of a WRITE request, the pseudo paging device driver sends an I / O request for page out and page out data to the paging service daemon process of another computer (step S).
6). Then, the completion of the request is returned to the requester (pseudo paging device driver) (step S5),
The process ends.

FIG. 8 is a diagram showing a processing flow of the above-described paging service daemon process. The paging service daemon process receives an I / O request from the pseudo paging device driver of another computer (Step S10). The paging service daemon process determines that the I / O request is
It is determined whether the request is an EAD request or a WRITE request for page out (step S11).

In the case of a READ request, data is read from a virtual memory (virtual address space) based on an I / O request received from a pseudo paging device driver of another computer (step S12). Finally, the data read from the virtual memory is sent to the pseudo paging device driver, which is a requester (step S13), and the process ends.

On the other hand, in the case of a WRITE request, the paging service daemon process receives data from a pseudo paging device driver of another computer which is a requester (step S14). Then, the received data is written into the virtual memory (virtual address space) (step S15), and the process ends.

Next, a case where a plurality of paging service daemon processes process a pseudo paging device driver of a computer will be described.

FIG. 9 shows an example in which four paging service daemon processes 100 to 103 perform the processing of the pseudo paging device driver of one computer. In this example, page-in data is arranged and stored in a format like RAID5 in the virtual memories 110 to 113 (virtual address spaces) of four paging service daemon processes. .., The virtual memory 111 stores the data blocks 1, 5,..., The virtual memory 112 stores the data blocks 2, 6,. Stores data blocks 3, 7,... Respectively.

FIG. 10 shows an example in which five paging service daemon processes 200 to 204 perform the processing of the pseudo paging device driver of a certain computer. In this example, page-in data is arranged and stored in a format like RAID5 in the virtual memories 210 to 214 (virtual address spaces) of five paging service daemon processes. .., The virtual memory 211 stores the data blocks 1, 5,..., The virtual memory 212 stores the data blocks 2, 6,. , The data y obtained by taking the exclusive-OR of the data block 3 and the data blocks 4 to 7 is stored in the virtual memory 214.
The data obtained by e-OR and the data block 7 are stored.

As described above, by storing data in a format such as RAID5, even if an arbitrary paging service daemon process stops operating, the data is stored in the paging service using data stored by another paging service daemon process. There is an advantage that necessary data can be restored.

[0043]

As described above, according to the present invention, paging data of a client computer (first computer) is stored in an address space managed by a paging service daemon process of a server computer (second computer). If the server computer has sufficient real memory, the paging of the client computer can be processed at an extremely high speed, so that an effect equivalent to an increase in the real memory of the client computer can be obtained. In particular, the technology described above has been made possible by recent high-speed networks. As a result, a computer in a network environment can be used efficiently only by increasing the memory of the server computer as necessary without increasing the memory of the client computer.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment according to a virtual storage system of the present invention.

FIG. 2 is a conceptual diagram of a second embodiment according to the virtual storage system of the present invention.

FIG. 3 is a detailed block diagram of a second embodiment according to the virtual storage system of the present invention.

FIG. 4 is a conceptual diagram of a third embodiment according to the virtual storage system of the present invention.

FIG. 5 is a detailed block diagram of a third embodiment according to the virtual storage system of the present invention.

FIG. 6 is a conceptual diagram of a virtual storage system according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram showing the operation of a pseudo paging device driver used in the present invention.

FIG. 8 is a block diagram showing the operation of a paging service daemon process used in the present invention.

FIG. 9 is a diagram showing a first storage state in which page-in data is stored in a virtual memory used in the present invention.

FIG. 10 is a diagram showing a second storage state in which page-in data is stored in a virtual memory used in the present invention.

[Explanation of symbols]

10, 41, 42, 43 ... client computer (first
20, 45, 50, 51 ... server computer (second computer) 10A ... process 12, 22, 451, 461, 501, 511 ... virtual memory 14, 24, 452, 462, 502, 512 ... real memory 16, pseudo paging device 18, 410, 420, 430 pseudo paging device driver 20A, 450, 460, 500, 510, 610, 6
20, 630: Paging service daemon process 26, 453, 463, 503, 513: Paging device

Claims (7)

[Claims] 1. A plurality of computer systems having a memory management device, comprising: a first computer system having a pseudo paging device serving as a paging destination of a real memory; and a pseudo paging device driver executing processing of the pseudo paging device. A second computer system having a paging service daemon process for receiving an I / O request issued by the pseudo paging device driver in response to page in / page out, wherein the paging service of the second computer system is provided. When a daemon process receives page-out data together with a page-out I / O request from the pseudo-paging device driver of the first computer, receives the page-out data and saves the page-out data in a virtual address space in its own system. When the paging service daemon process of the second computer system receives a page-in I / O request from the pseudo paging device driver of the first computer, the paging service daemon process saves the page-in I / O request in a virtual address space in the own system. A paging control method for a virtual storage system, comprising sending back existing data as page-in data to the first computer system. 2. A plurality of paging service daemon processes are provided in the second computer system, and the I / O request from the pseudo paging device driver of the first computer system is transmitted to the plurality of paging service daemon processes. 2. The paging control method for a virtual storage system according to claim 1, wherein the paging control method is used to perform processing. 3. The paging service daemon process is provided in a plurality of the second computer systems, and the I / O request from the pseudo paging device driver of the first computer system is transmitted to the plurality of second computers. 2. The paging control method for a virtual storage system according to claim 1, wherein the paging service daemon process in the system shares and processes the paging service. 4. A paging control method for a virtual storage system according to claim 3, wherein said page-in data and page-out data are striped to a plurality of said paging service daemon processes. 5. The system according to claim 5, wherein the page-in data and the page-out data are stored in a virtual memory of the second computer by a plurality of paging service daemon processes.
4. An arrangement according to claim 3, wherein the information is arranged and stored.
A paging control method for a virtual storage system according to the above. 6. The system according to claim 6, wherein the page-in data and the page-out data are stored in a virtual memory of the second computer by a plurality of paging service daemon processes.
Even if one of the paging service daemon processes is stopped, the data corresponding to the stopped process is restored from the other page-in data or page-out data. The paging control method for a virtual storage system according to claim 5. 7. A plurality of computer systems having a memory management device, comprising: a first computer system having a pseudo paging device serving as a paging destination of a real memory; and a pseudo paging device driver executing processing of the pseudo paging device. A paging service daemon process for receiving an I / O request issued by the pseudo paging device driver in response to page-in / page-out.
And the paging service daemon process of the second computer system receives the page-out data together with the page-out I / O request from the pseudo-paging device driver of the first computer. Means for receiving a page-in I / O request from the pseudo-paging device driver of the first computer by the paging service daemon process of the second computer system. Means for sending back data stored in the virtual address space in the own system to the first computer system as page-in data, comprising: a paging control device for the virtual storage system. .