JPH07152643A - Virtual storage system - Google Patents

Abstract

PURPOSE:To provide the virtual storage system which is highly flexibly by performing flexible data conversion at the time of a page-in and a page-out process as to a virtual storage system which employs a paging system. CONSTITUTION:When a memory management device 1 sends a page-in indication to a pager 2, data before conversion which are read in a temporary storage device 5 from a magnetic disk device 6 or paged out and present in the temporary storage device 5 are converted by a data converting device 4 by the indication of the pager 2 and written in a specific page of a main storage device 3. When a page-out indication is made, the data converting device 4 performs data conversion and writes the data in the temporary storage device 5 and the page is released. Information for the switching of the data conversion and the switching of paging operation is stored in, for example, a paging table and on the basis of the table, the data converting process and paging process are carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data processor virtual storage system, and more particularly to a paging type virtual storage system.

[0002]

2. Description of the Related Art A conventional paging type virtual storage system includes a main storage device and an auxiliary storage device, divides a virtual storage area into pages, and divides the entire main storage device into page frames. However, data is transferred between the main storage device and the auxiliary storage device in page units. The virtual memory system based on the paging system has spread so that it can be used not only in mainframe computers but also in workstations and personal computers.

For example, Rashid, R .; Others, "Mac
Hine-Independent Virtual M
emory Management for Page
dUniprocessor and Multipr
processor Architectures ”, CM
U Technical Report, Vol. C
The external pager of Mach OS described in MU-CS-87-140 (1987) handles page-in and page-out requests as messages,
It is possible to perform paging operations in kernel space, user space, own host, or remote host.

Also, Tatsuya Ogino et al., "ToM Microkernel," IEICE Transactions D-1, Vol. J7
5-D-1, No. 8, pp555-562 (199
In the virtual storage system of ToMOS described in 2), page faults and page out requests are abstracted as events. When a page fault event occurs, the kernel reserves a physical page and the event processing thread makes a remote procedure call to the pager entry for page in processing. If a page-out is required to secure a physical page, a page-out event is generated for the virtual page to be paged out, and the event processing thread calls the remote procedure for the pager entry for page-out processing. Do.

Further, in Japanese Laid-Open Patent Publication No. 62-197843 and Japanese Laid-Open Patent Publication No. 1-169555, a file in an auxiliary storage device is mapped in a virtual storage space and accessed to replace input / output to / from the file. And a virtual external storage device that performs input / output using a virtual storage management mechanism.

In each of the above virtual memory management systems, data transfer between the auxiliary memory device and the main memory device is performed by the data itself transferred to the main memory device.
In recent years, for example, as in the case of image processing, a large amount of data is used, the capacity of the auxiliary storage device required for paging is increased, and the transfer efficiency between the auxiliary storage device and the main storage device is increased. Is a problem.

In order to deal with such a problem, in some conventional systems, it is considered that data is compressed or expanded during paging.
For example, JP-A-4-14154 and JP-A-62-
In the system described in Japanese Patent No. 154152, the data in the main storage device is compressed and written to an unused area of the auxiliary storage device, and the compressed data in the auxiliary storage device is decompressed and restored and read into the main storage device. This saves the area on the auxiliary storage device and transfers data in a compressed form to improve the transfer efficiency.

On the other hand, as computers have become common as information equipment and are used for personal use, it is necessary to perform pre-processing and post-processing such as information encryption, information compression, gradation conversion and resolution conversion of image information. Is increasing. Conventionally,
Such pre-processing and post-processing such as information encryption, information compression, image information gradation conversion and resolution conversion are performed by a dedicated program, or are executed by being incorporated in an application program. There is.

In many cases, these processes are performed before and after the process desired by the user. Therefore, a mechanism for efficiently performing these processes on the system side is desired. As one of them, it is conceivable to perform these pre-processing and post-processing in the virtual memory system.

In the above-mentioned conventional virtual memory system, compression / expansion is performed at the time of data transfer, but it has not been considered at all to perform other processing at the time of data transfer. This is because the conventional system aims only to efficiently use the auxiliary storage device and improve the transfer efficiency. Further, in the conventional system, the compression and decompression processes are always performed at the time of data transfer, and cannot be selectively performed according to the type of data, the state of the system, or the intention of the user.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and in a paging-type virtual storage system, not only is data transferred at the time of page-in or page-out, It is an object of the present invention to provide a highly flexible virtual storage system by performing flexible data conversion.

[0012]

According to the present invention, in a page-type virtual storage system, a main storage device, storage management means for managing at least the main storage device, and data transfer information holding for holding information relating to data transfer. A page for referring to a means, a data conversion information holding means for holding information about data conversion, a data conversion means for performing data conversion on transfer data, and a data transfer information held in the data transfer information holding means. A unit data transfer is performed, and a predetermined data conversion instruction to the data conversion means and a management instruction to the storage management means are issued to the data conversion means based on the data conversion information held in the data conversion information holding means at the time of the data transfer. It is characterized by having a pager for performing.

The pager transfers data in page units between an auxiliary storage device or a temporary storage device and the main storage device, or between a paging target area and a non-paging target area in the main storage device, At the time of data transfer, the data conversion means may be configured to perform data conversion on the transfer data.

At this time, when the pager transfers data in page units between the paging target area and the non-paging target area in the main storage device, the storage management means is configured such that the data conversion information holding means is It is possible to manage so that a predetermined page paged out to the non-paging target area in the main storage device is not erased based on the held information about the data conversion. Further, when the pager transfers data in page units between the main storage device and the auxiliary storage device, the storage management means does not convert the data in the main storage device by the data conversion means. It can be configured so that it cannot be paged out to the auxiliary storage device.

Further, the data conversion means has a plurality of data conversion processes, selects one or a plurality of data conversion processes from the plurality of data conversion processes according to an instruction from the pager, and outputs data by the pager. It can be configured such that the selected data conversion processing can be performed on the transfer data at the time of transfer.

A plurality of data conversion processes are selected by selecting a result of executing a predetermined procedure, a parameter designated by the user,
It can be configured to be performed based on information such as system status and page attributes.

Further, the data conversion means can be configured so that a predetermined data conversion procedure prepared by the user can be registered.

[0018]

According to the present invention, the information about the data transfer and the information about the data conversion can be held, and the pager refers to the information about the data transfer to perform the data transfer on a page-by-page basis. At this time, the data conversion means automatically performs a predetermined data conversion based on the information regarding the data conversion. for that reason,
The data conversion can be flexibly performed according to the setting of the information regarding the data conversion. At this time, since the data conversion that has been conventionally performed by the application is performed by the data conversion means at the time of data transfer during paging, it is not necessary to prepare a program for data conversion on the application side, and the development and configuration of the application program are performed. Will be easier.

The target of data transfer by the pager can be between the auxiliary storage device or the temporary storage device and the main storage device, or between the paging target area and the non-paging target area in the main storage device, In particular, in the data transfer between the temporary storage device and the main storage device, or between the paging target area and the non-paging target area in the main storage device, the data conversion means converts the transfer data to the transfer data during the data transfer. By performing the data conversion by the data conversion, high-speed data transfer and data conversion can be realized.

When the pager transfers data in page units between the paging target area and the non-paging target area in the main storage device, the storage management means stores the data in the main storage device based on the information regarding the data conversion. It is possible to manage not to delete a predetermined page that is paged out to the non-paging area. Therefore, for example, by storing the data before conversion without erasing it, not only the converted data that was paged in but also the data that was paged out before conversion can be accessed from the process. can do.

When the pager transfers data in page units between the main storage device and the auxiliary storage device, the data in the main storage device is not converted by the data conversion means and is not paged out to the auxiliary storage device. In addition, by managing the storage management means, for example, after the encrypted data is decrypted and transferred to the main storage device, the decrypted data is prevented from being paged out to the auxiliary storage device as it is, and the confidentiality is maintained. be able to.

The data conversion means has a plurality of data conversion processes, selects one or a plurality of data conversion processes from the plurality of data conversion processes according to an instruction from the pager, and transfers the data by the pager. By performing the selected data conversion process on the transfer data, it is possible to perform flexible data conversion corresponding to various states at the time of data transfer. The choice of data conversion process is
For example, it can be performed based on the result of executing a predetermined procedure, parameters specified by the user, system status, page attributes, and the like.

Further, the data conversion means can be configured so that a predetermined data conversion procedure prepared by the user can be registered, and a flexible data conversion more suited to the user's intention can be realized.

[0024]

1 is a block diagram showing an embodiment of a virtual storage system of the present invention. In the figure, 1 is a memory management device, 2 is a pager, 3 is a main storage device, 4 is a data conversion device, 5 is a temporary storage device, and 6 is a magnetic disk device.

The main memory 3 is divided into areas having a certain storage capacity, that is, pages, and managed in page units. The temporary storage device 5 is also divided into pages,
It is managed in page units. The page sizes of the main storage device 3 and the temporary storage device 5 do not have to be the same. The temporary storage device 5 holds data transferred to and from the magnetic disk device 6 and data transferred to and from the main storage device 3 before conversion by the data conversion device 4. It In the following description, the data before conversion refers to the data before conversion of the transfer data to the main storage device 3, and the data after conversion refers to the data that has been converted to the data transferred to the main storage device 3. Show. When paged out from the main storage device 3, it is assumed that the converted data is converted into the data before conversion by the data conversion device 4. The magnetic disk device 6 is managed in units of blocks divided into areas having a certain storage capacity. This block does not necessarily have to be the same size as the page.

The memory management device 1 manages the main storage device 3 and the temporary storage device 5, for example, allocates and releases pages and manages empty pages. In addition, the memory management device 1 has an address in the virtual storage space, a real address in the main storage device 3, an address of data saved in the temporary storage device 5, and the magnetic disk device 6 as well.
It has a page table for managing the addresses of. Address conversion from a logical address to a physical address is performed using this page table. This page table also holds information for data conversion.

The pager 2 refers to the page table held in the memory management device 1 and refers to data between the main storage device 3 and the temporary storage device 5 and between the temporary storage device 5 and the magnetic disk device 6. Transfer. When performing data transfer between the main storage device 3 and the temporary storage device 5, the page table is referred to, and according to the information for performing the data conversion, the data conversion specified for the transfer data is performed if necessary. The data conversion device 4 is instructed to perform.

The data converter 4 performs a predetermined conversion process on the transfer data when the pager 2 transfers the data. The data conversion device 4 can prepare a plurality of data conversion methods. For example, the first conversion method,
It is possible to prepare a second conversion method that is the reverse conversion, and apply the first conversion method at the time of page-in and the second conversion method at the time of page-out. At this time,
The first conversion method is to convert the pre-conversion data into the post-conversion data, and the second conversion method is to convert the post-conversion data back into the pre-conversion data. The data conversion performed by the data conversion device 4 is not limited to the reversible conversion, and the result obtained by applying the second conversion method to the converted data may be different from that before the conversion. Further, only one conversion method may be used, and in this case, bidirectional conversion may be performed by one conversion method. For example, when the black and white inversion processing of an image is used as a conversion method, bidirectional conversion can be performed by one conversion method. Furthermore, a large number of conversion methods can be built in and switched. Of course, the pager 2 can also select not to perform the conversion by the data conversion device 4 based on the information for performing the data conversion in the page table. It is also possible to register a conversion method in which no conversion is performed in the data conversion device 4 and select this, or to bypass the data conversion device.

In this embodiment, a temporary storage device 5 is provided between the main storage device 3 and the magnetic disk device 6, and the data conversion device 4 uses the temporary storage device 5 when transferring data between the temporary storage device 5 and the main storage device 3. An example of performing data conversion is shown. Of course, it is also possible to directly transfer data between the main storage device 3 and the magnetic disk device 6 without using the temporary storage device 5. Alternatively, a plurality of temporary storage devices may be used. Alternatively, the main memory 3 may be divided into a paging target area and a non-target area, and paging may be performed between them. The present invention is generally applicable to hierarchical storage devices.

Further, instead of the magnetic disk device 6, an optical disk device or a magneto-optical disk device, a floppy device, a silicon disk device using a semiconductor memory,
One or more of various devices such as a tape device capable of random access or a combination of a plurality of types of devices may be used.

In this embodiment, the data conversion by the data conversion device 4 is performed on the transfer data between the main storage device 3 and the temporary storage device 5, but at the time of page-in, for example, after the data conversion. The data may be temporarily stored in the temporary storage device 5 and then transferred. When the page-out is performed, the data may be stored in the temporary storage device 5 and then converted. In that case, the data conversion device 4 can also record the data before conversion and the data after conversion in another temporary storage device 5 or another area of the temporary storage device 5.

FIG. 2 is an explanatory diagram of an example of the page table. In the page table shown in FIG. 2, one entry is assigned to each page assigned to the virtual space. One entry is composed of a virtual address part, a real address part, a flag part 1, a temporary storage device address string part, a flag part 2, a magnetic disk device address string part, an offset part, and an action part.

The real address section holds the address of the page in the main storage device 3 where the real data of the page in the virtual space is held. The flag 1 copy records that the data in the page in the main storage device 3 has been updated. That is, when the page is paged in, the flag 1 part is cleared as an initial state, is marked when there is a change access to the page in the main storage device 3, and is cleared when the page is paged out. To be done.

The temporary storage device address string portion holds a string of addresses on the temporary storage device 5 in which data required as data before conversion of a page in the virtual space is cached. The flag 2 part records that the data on the page in the temporary storage device 5 has been updated. That is, when the page is read from the magnetic disk device 6, the flag 2 part is cleared as the initial state,
The page is marked when the page is written by the data conversion device 4, and cleared when the page is written to the magnetic disk device 6.

The magnetic disk device address string portion holds a string of addresses of blocks on the magnetic disk device 6 required as data before conversion of a page in virtual storage. When the data of the page on the virtual memory is converted by the data converter 4 from the data before conversion described in the magnetic disk device address string, the offset unit is in which page of the data after conversion. Holds the information of.

The action section holds information used for data conversion by the data conversion device 4 and processing information performed by the memory management device 1 at the time of paging for a page in virtual storage. For example, whether or not to perform conversion using the data conversion function of the data conversion device 4 and whether the data conversion device 4 has a large number of data conversion methods,
Indicates which data conversion method to use. It is also used to instruct the memory management device 1 not to page out the data before conversion. In the following description of this embodiment, it is assumed that the data conversion device 4 performs data conversion when the action part is marked.

In the example shown in FIG. 2, the virtual address Av1
The data corresponding to is not paged in to the main storage device 3. Further, since an ID indicating conversion is described in the action part, it indicates that the data conversion device 4 performs predetermined data conversion at the time of paging. The data before conversion used at the time of page-in is stored in the temporary storage device 5.
Are already stored in the addresses Ab1 and Ab2, and the data before the conversion are stored in the addresses Ad1 and Ad2 on the magnetic disk device 6. Since the offset is 0, the data conversion device 4
The data of the first page is loaded into the main storage device 3 as real data corresponding to the virtual address Av1. At this time, the virtual address Av
The actual data corresponding to 2, Av3, Av4 may also be created by data conversion, but since it is already loaded on the main storage device 3, it is not loaded again. However, a page in which the flag M is not added to the flag part 1 may be loaded.

The data corresponding to another virtual address Av2 is loaded into the address Ar2 on the main storage device 3, is modified by the data processor, and the flag M is attached to the flag 1 part. Therefore, when this page is paged out, data transfer from the main storage device 3 to the temporary storage device 5 occurs. Since the ID indicating the conversion is described in the action part, since the data conversion is performed by the data conversion device 4, the data is transferred to the temporary storage device 5.

In the above embodiment, the temporary storage device address string and the magnetic disk device address string hold the addresses of the respective devices, but the present invention is not limited to this.
The head of the address may be an ID, and this ID may be held, or another ID may be held. Further, in the above-described embodiment, the page table is held by the memory management device 1, but the present invention is not limited to this, and the pager 2 may be held or may be held by the page table management unit. You can also Further, in the example shown in FIG. 2, the page table holding the information on the data transfer is configured to include the column of the action section which is the information on the data conversion, but it is configured to separately manage the information on the data conversion. You can also do it. In that case,
The information regarding the data conversion can be configured to be held by the memory management device 1, the data conversion device 4, or another management unit.

The operation of one embodiment of the virtual storage system of the present invention will be described with reference to FIGS. 1, 2 and 3 to 14. In the following description of the operation, in the case of using a specific example, the magnetic disk device 6 stores encoded data, and the data conversion device 4
Is provided with a conversion means for performing decoding as a first conversion method and a conversion means for performing encoding as a second conversion method.

FIG. 3 is an explanatory view of the outline of the operation in one embodiment of the virtual storage system of the present invention. In FIG. 3, the address space of the main storage device 3 is shown as a physical address space. If the accessed page does not exist in the main storage device 3, the page-in operation is performed. If the data before conversion of the data to be transferred does not exist in the address space of the temporary storage device 5, first, the disk block DB1 is read from the magnetic disk device 6 into the address space of the temporary storage device 5. This operation is indicated by.
The page BB1 read in the address space of the temporary storage device 5 or paged out and existing in the address space of the temporary storage device 5 is read by the data conversion device 4 according to an instruction from the pager 2, and, for example, 1
The data is converted by the above conversion method and written in a predetermined page of the physical address space. This operation is indicated by. A predetermined page for writing data in the physical address space is secured from an empty page managed by the memory management device 1.

For example, in the case of the above-mentioned encoding and decoding,
In data conversion such as processing such as compression and expansion, the amount of data changes between the pre-conversion data and the post-conversion data. Also,
Even in image processing, the data amount may change due to data conversion. When decoding is performed as the first conversion method, for example, as shown in FIG. 3, for the data of one page before conversion, the data amount of the converted data increases due to the data conversion, and, for example, the data of pages RB1 and RB2 It shows the case where two pages are required. When you page in,
It is not necessary to load these two pages in the physical address space at the same time, and they may be selectively loaded. At this time, the page to be loaded can be known by referring to the offset part of the page table. In addition, when loading all pages, it is necessary to know the converted data amount in advance and secure an area in the physical address space. In that case, it is not necessary to secure consecutive pages. The converted data amount can be stored in advance in the page table.

When there are no free pages in the physical address space, or when there are no free pages, page out is performed. A conventionally used method can be used to select a page to be paged out, for example, the LRU method can be used. In addition, the page required by the second conversion method is also selected together with the selected page. This page can be known by searching for the same page in the address column portion of the temporary storage device of the page table. If these pages have not been updated, they can simply be released as free pages. If it has been updated, the data is transferred to the temporary storage device 5. This operation is indicated by. Whether or not it has been updated can be known by referring to the flag 1 part of the page table.

At the time of data transfer to the temporary storage device 5, the data conversion device 4 performs data conversion by the second conversion method. For example, page RB in the physical address space
1, RB2 are read out, converted into one page of encoded data by the second conversion method for encoding, and stored in page BB1 of the address space of the temporary storage device 5. At this time, RB1 and RB2 in the physical address space are released as empty pages and the flag 2 of the page table is marked.

After that, the data is written in a predetermined block DB1 of the magnetic disk device 6 at a predetermined timing.
When the data is written to the magnetic disk device 6, the flag 2 of the page table is cleared.

FIG. 4 is a flow chart for explaining the page-in operation in the embodiment of the virtual memory system of the present invention. When a page not resident in the main storage device 3 is referenced in S101, the memory management device 1
After confirming an empty page in S103, the pager 2 is instructed to page in the referenced page in S104. Upon receiving the page-in instruction from the memory management device 1, the pager 2 refers to the page table in S105 and selects a column of virtual pages to be page-in. This column of virtual pages shall include at least the referenced page. As the row of virtual pages, for example, a plurality of virtual pages for which data conversion is performed together with the referenced page can be selected. It is desirable to select the virtual page sequence so that the cost is as low as possible. When the number of empty pages in the main storage device 3 is small in S102, page out is performed and then page in is performed in S103. The number of pages actually paged in must be less than the number of free pages.

In step S106, the pager 2 instructs the memory management device 1 to secure in the main storage device 3 pages in the real space having the size (number of pages) of the selected virtual page sequence. The memory management device 1 reserves as many pages in the main storage device 3 as the number of pages requested by the pager 2 and changes the corresponding entry in the page table.

In step S107, the pager 2 refers to the page table and checks whether or not all the pre-conversion data in the temporary storage device 5 corresponding to the virtual page sequence exist. If even one does not exist, in S108, the memory management device 1 is instructed to secure an area of the number of pages that does not exist in the temporary storage device 5. Here, the number of pages required on the temporary storage device 5 is the number of pages corresponding to the area required to load the corresponding block of the magnetic disk device 6, and when the page size and the block size are the same. In addition, the number of blocks on the magnetic disk device 6 and the number of pages required on the temporary storage device 5 are the same. The memory management device 1 reserves the area of the number of pages requested by the pager 2 in the temporary storage device 5, and changes the corresponding entry in the page table. The pager 2 loads necessary pages on the magnetic disk device 6 into an area secured on the temporary storage device 5.

In step S109, the pager 2 requests the data conversion device 4 to perform data conversion and data transfer for the unconverted data arranged in the temporary storage device 5.
Upon receiving the data conversion request, the data conversion device 4 performs data conversion on the data before conversion in the temporary storage device 5, and writes the converted data in the page row on the main storage device 3. For example, the data conversion device 4 performs a decoding process on the encoded pre-conversion data on the temporary storage device 5, and writes the decoded post-conversion data to the main storage device 3. When there are a plurality of units for encoding and decoding, the unit specified by the ID of the action part of the page table can be configured to request conversion.

By the above-mentioned operation, data conversion can be performed on the page-out pre-conversion data, and the necessary page can be page-in on the main storage device 3.

5 to 8 are explanatory views of an example of page-in operation in the embodiment of the virtual storage system of the present invention. Now, as shown in FIG. 5, page A in the real space is
It is assumed that r1 is loaded. In this state, when the CPU attempts to access the virtual address included in the page Av2 of the virtual space, the memory management device 1
Refers to the page table and converts the address into an address in real space. At the time of this conversion, it is understood that the page of the real space including the address of the real space is not resident in the main storage device 3. At this time, the memory management device 1
Causes a page fault and shifts to paging processing. Here, the pager 2, along with the page Av2,
Pages Av3 and Av4 other than the page Av2 are simultaneously selected as pages to be paged in.

In FIG. 6, page Av in the virtual space
Secure pages Ar2, Ar3, Ar4 in the real space for storing data 2, Av3, Av4 in the main memory,
Update the page table. Here, the page Ar1 in the real space corresponding to the page Av1 in the virtual space already exists. Pages Av2 and Av for pager 2
3, request Av4 page-in. Alternatively, if the update flag of page Av1 is not marked, page A
You may make it page-in also to v1.

The pager 2 which has received the page-in request
Referring to the page table, the page Av2 in the virtual space
It is checked that the blocks of the magnetic disk device 6 required to page in Av3 and Av4 are blocks Ad1 and Ad2. Further, by referring to the page table, the blocks Ad1 and Ad2 of the magnetic disk device 6 are
However, it is found that they are not loaded on the temporary storage device 5. The pager 2 is a block Ad of the magnetic disk device 6.
The memory management device 1 is requested to secure a page on the temporary storage device 5 for loading 1, Ad2. Memory management device 1 that has received a request to secure a page on temporary storage device 5
Page Ab on the temporary storage device 5 as shown in FIG.
1, Ab2 are reserved, the corresponding entry in the page table is updated, and the completion of the reservation is notified to the pager 2.

Pages Ab1 and Ab2 on the temporary storage device 5
The pager 2 which has been notified of the completion of the reservation of the data loads the data in the blocks Ad1 and Ad2 of the magnetic disk device 6 into the pages Ab1 and Ab2 in the temporary storage device 5. Then, the data conversion device 4 uses the page A on the temporary storage device 5.
The data of b1 and Ab2 are converted to generate the converted data of 4 pages. Of these pages, the second to fourth pages are pages Ar2, Ar3, Ar on the main storage device 3, respectively.
Write to 4. This state is shown in FIG. Of the converted data, the first page is the page Ar1 in the main memory
This page does not need to be reloaded, because this page is already loaded.

In the state shown in FIG. 8, the virtual address included in the page Av2 of the virtual space accessed by the CPU can be converted into a real address, and the CPU accesses the main storage device 3.

FIG. 9 is a flow chart for explaining the page-out operation in the embodiment of the virtual memory system of the present invention. When the pages in the main storage device 3 are insufficient, for example, the number of free pages in the main storage device 3 becomes less than or equal to the first predetermined amount, the memory management device 1 instructs the pager 2 to page out in S111. To do. Further, the memory management device 1 selects a page to be paged out from the main memory in S112. The pager 3 may select the page to be paged out. For this selection method, a method similar to that of the conventional virtual memory system is adopted. For example, the LRU method or the like can be used.

In S113, the pager 2 refers to the page table and checks whether or not all the pages of the selected page row exist in either the temporary storage device 5 or the magnetic disk device 6. If it does not exist, there should be a page in main memory that is paged out at the same time as the selected page. If the main memory has not been allocated yet, a free page is actually allocated or a dummy page is allocated.

In step S114, the pager 2 inquires of the data conversion device 4 about the size of the pre-conversion data obtained by data conversion of the pre-conversion data of the page to be paged out at the same time, and in step S115, the data is returned. The memory management device 1 is requested to secure an area of only the size on the temporary storage device 5. If the size of the pre-conversion data does not depend on the post-conversion data and is a constant ratio, an inquiry to the data conversion device 4 is unnecessary. The memory management device 1 secures an area of the requested size on the temporary storage device 4, and writes the address string of the page in the page table in S116.

In step S117, the pager 2 causes the data converter 4 to convert the data of all pages that are paged out at the same time and write the converted data into the page in the temporary storage device 5 secured by the memory management device 1. Give instructions. When the data conversion device 4 has a plurality of data conversion methods, the pager 2 refers to the page table and instructs the data conversion device 4 to select the specified data conversion method. . The data conversion device 4 performs data conversion of the requested data of the page sequence and writes the data in the page on the temporary storage device 5 secured by the memory management device 1.

The pager 2 determines in step S118 that the main memory 3
It instructs the memory management device 1 to release the upper page. The memory management device 1 adds the page to be released on the main storage device 3 to the unused page set, and updates the page table in S119.

Further, the pager 2 may be configured to write the page-out page in the temporary storage device 5 to the magnetic disk device 6.

In S113, if all the pages of the selected page sequence exist in either the temporary storage device 5 or the magnetic disk device 6, in S120, all the pages of the selected virtual page are stored. Determine if no changes have been made. If no changes have been made, it is not necessary to save to the temporary storage device 5. Therefore, the pager 2 instructs the memory management device 1 to release the selected page in the main storage device 3 in S118. The memory management device 1 adds the page to be released on the main storage device 3 to the unused page set, and updates the page table in S119.

In S120, if at least one page of the selected virtual page has been changed, in S121, the pager 2 checks the page table and simultaneously page-in all pages to be paged out. Therefore, the first predetermined amount for starting the above-described page-out process needs to be larger than the number of pages that are paged out at the same time.

When the pages to be paged out at the same time are paged in, the process proceeds to S117, where the pager 2 performs data conversion on the data of all pages to be paged out at the same time to the data conversion device 4, and the corresponding temporary data is converted. It is instructed to write to a page on the storage device 5. At this time, since the area on the temporary storage device 5 is secured at the time of page-in in S121, it is not necessary to secure the area again.

In step S118, the pager 2 releases the selected page on the main storage device 3 by the memory management device 1.
Instruct. The memory management device 1 adds the page to be released on the main storage device 3 to the unused page set, and updates the page table in S119. In addition, pager 2
May be configured to write the page in the temporary storage device 5 to the magnetic disk device 6.

In S122, the pager 2 determines whether or not the number of empty pages has become equal to or larger than the second predetermined amount, and the processing after S112, that is, until the number of empty pages becomes equal to or larger than the second predetermined amount, that is, The process of finding the page to be paged out and releasing the page in the main memory is continued.

Data transfer from the temporary storage device 5 to the magnetic disk device 6 can be performed at the time of page-out as described above. Alternatively, it may be started by detecting that the number of empty pages in the temporary storage device 5 becomes smaller than the third predetermined amount. The data transfer to the magnetic disk device 6 can be configured such that the data transfer is performed until the number of empty pages in the temporary storage device 5 becomes equal to or larger than the fourth predetermined amount.

10 to 14 are explanatory views of an example of the page-out operation in the embodiment of the virtual storage system of the present invention. Now, as shown in FIG. 10, pages Ar2, Ar3, and Ar4 are loaded in the real space. In this state, it is assumed that there are not enough pages in the main storage device 3, the page-out process is activated, and pages Ar2, Ar3, and Ar4 are selected as pages to be paged-out.
At this time, the pager 2 selects page A from the page table.
Check for pages that need to be paged out at the same time as r2, Ar3, Ar4. Here, page A of the virtual space
v1 is selected as the page to be paged out at the same time.

In the search for pages to be paged out at the same time, for example, in the example of FIG. 10, the pages that need to be paged out (encoded) at the same time are grouped by the ID of the virtual address. ID
Can be searched by. Alternatively, the same page in the temporary storage device address sequence or the magnetic disk device address sequence can be selected. Alternatively,
By adding a column to the page table that holds the IDs of pages that need to be paged out at the same time,
You can also make the search easier.

On the other hand, from the change mark attached to the flag 1 part of the page table, it can be seen that the data of the page Ar2 in the real space has been changed. Further, since the page marked with the change mark is not paged out, the page Ar2 exists only in the main memory, and the data of the changed page Ar2 does not exist in the temporary storage device 5 and the magnetic disk device 6. According to the flowchart shown in FIG. 9, in S121, the process of page-in the necessary page is executed.

Here, it can be seen from the page table that the data of page Av1 in the virtual space is not assigned to the real space. Therefore, it is necessary to load the data of page Av1 in the virtual space into the real space. Further, it is understood that in order to load the data of the page Av1 in the virtual space into the real space, the areas Ad1 and Ad2 on the magnetic disk device 6 need to be loaded onto the temporary storage device 5. Further, from the page table, it can be seen that the area Ad1 on the magnetic disk device 6 has already been loaded on the page Ab1 on the temporary storage device 5, so only Ad2 needs to be loaded.

The pager 2 is different from the memory management device 1 in that
A request is made to secure an area for loading data in the area Ad2 on the magnetic disk device 6. The memory management device 1 receiving the request stores the page Ab2 in the space on the temporary storage device 5.
Area is secured and the address of page Ab2 is set to pager 2
Tell. The pager 2 loads the data in the area Ad2 onto the page Ab2 on the temporary storage device 5. At the same time, the pager 2 receives the virtual addresses Av1 and Av of the page table.
The page Ab2 is added to the temporary storage device address columns of the entries 2, 2, Av3, Av4. This state is shown in FIG.

The memory management device 1 uses the page A of the virtual space.
A page Ar1 is secured in order to place v1 data in the real space. The decoding unit of the data conversion device 4 decodes the data of the pages Ab1 and Ab on the temporary storage device, and writes the first page of the decoded data to the page Ar1 of the real space. This state is shown in FIG.
Now, all the pages required for data conversion are arranged in the main memory.

The encoding unit of the data conversion device 4 encodes the data of the pages Ar1, Ar2, Ar3, Ar4 in the real space, and the pages Ab1, A in the temporary storage device 5 are encoded.
Write to b2. The pager 2 clears the change mark of the real address of the entries of the virtual spaces Av1, Av2, Av3, Av4 of the page table and puts the change mark on the temporary storage device address column. This state is shown in FIG.

The pager 2 writes the data of pages Ab1 and Ab2 on the temporary storage device 5 to the areas Ad1 and Ad2 on the magnetic disk device 6, and makes entries of pages Av1, Av2, Av3 and Av4 in the virtual space of the page table. Clear the change mark attached to the temporary storage device address column.

The memory management device 1 uses the page A in the real space.
r1, Ar2, Ar3, Ar4 are released, and pages Av1, Av2, Av3, Av in the virtual space of the page table are released.
Clear the real address of entry 4. This state is shown in FIG. In this way, the pages Ar2, Ar3, Ar4 in the real space can be paged out.

In the above description, the paging operation of the data already mapped in the virtual space has been described. For example, a new file is opened and mapped in the virtual space. Usually, data conversion is often decided according to the data. Therefore, when a new file is opened, the page table is set for data conversion. The data conversion procedure to be set can be set by the system or specified by the user.

As an example, a method of selecting a conversion method desired by the user from a plurality of data conversion methods prepared by the system when the opened file is mapped to the memory will be described. In the application program, after opening the file, the memory map system call is used to map the data of the file to an array, for example. Examples of the memory map system call include, for example, Sun Micro Systems In
For example, there is a Sun OS mmap system call. In addition to the conventional memory map system call argument, the number of the first data conversion method and the number of the second data conversion method are added. At this time, for example, the first data conversion method is a data conversion process for converting the data in the disk block into the data to be transferred to the main memory device, and the second data conversion method is the data conversion process from the data in the main memory device to the disk block. It can be a data conversion process for converting to data.

When the memory map system call is performed, a virtual block identifier, for example, the ID of the virtual address shown in FIG. 2 is assigned, and the pager 2 is assigned the virtual block identifier, the first conversion method, and the second conversion. Method tuples are sent. In the pager 2, an entry corresponding to the virtual block identifier is reserved in the page table, and the reserved entry has a column of the first data conversion method number, the second data conversion method number, and the block identifier of the pre-conversion data, respectively. Assign Here, the block identifier is
An identifier attached to a disk block of a magnetic disk device. For example, in the example of the page table shown in FIG. 2, it corresponds to a magnetic disk device address column. The number of the first data conversion method and the number of the second data conversion method are described in the action section.

Either the first data conversion method or the second data conversion method may be designated, or both may not be designated. The unspecified data conversion method may be assigned a default conversion method in the system, or may be configured to indicate that no conversion is performed by the data conversion device 4.

This example is particularly effective when the data conversion device 4 has a plurality of data conversion methods, and the data conversion methods can be switched and used according to the file used by the application. Also, if the user is O
The data conversion method can be explicitly specified at the S command level. In this case, for example,
By copying the file, it becomes possible to perform data conversion of the file data.

It is also possible to execute a data conversion procedure prepared by the user. As an argument of the above memory map system call, for example, when designating the first data conversion method and the second data conversion method, the entry address of the data conversion procedure is given.
When the memory mapping is performed and the page-in is performed, the pre-conversion data is mapped in the user process space. When converting the pre-conversion data, the system calls back the user process to the entry address of the first data conversion procedure, and the converted data is written in the corresponding post-conversion data page. Then, the system returns to the system mode and the page-in process ends.

When there are a plurality of data conversion procedures in the data conversion device 4, various selection methods are available as a method for selecting these, in addition to the above-mentioned method of explicitly selecting the data conversion procedure by the user or application. Can be used. Hereinafter, some selection methods will be described.

First, the data conversion method can be selected by executing a predetermined procedure. In this example, the data conversion device 4 holds and manages a procedure table showing the correspondence between the result of evaluation of the procedure and the data conversion method. In the data conversion step, the data conversion device 4 evaluates a predetermined procedure set in advance, determines the data conversion method corresponding to the result by referring to the procedure table, and determines the data conversion method according to the determined data conversion method. Perform data conversion. The predetermined procedure executed to determine the data conversion method may be provided commonly for page-in and page-out, or may be provided separately.

As another selection method, a data conversion method can be selected by a parameter. The parameters are
It may be input by the user or may be set by the application. A parameter storage unit is newly provided in the data conversion device 4, and a parameter table representing a data conversion method corresponding to each parameter is held and managed. The data conversion device 4 receives an input of a parameter and stores it in the parameter storage unit.

In the data conversion step, the data conversion device 4 accesses the parameter storage unit to take out the parameter. Then, referring to the parameter table, the data conversion method corresponding to the extracted parameter is checked, and the data conversion is executed by the obtained data conversion method.

In the case of this example, the direction of data transfer can be used as one parameter to switch between the first conversion method and the second conversion method. Also, instead of referring to the parameter table, the parameters are evaluated by a predetermined procedure,
The data conversion method may be determined.

Further, the data conversion method can be selected by using the system state as a parameter. The data conversion device 4 is additionally provided with a system state detection unit and a state table showing the correspondence between the system state and the data conversion method. In the data conversion step, the data conversion device 4 determines which system state is used as a parameter in order to select the data conversion method. The parameter to be used may be determined in advance, or which system state is selected as the parameter may be determined by executing a predetermined procedure. When the system state as a parameter is determined, the state table is referred to, the data conversion method is determined, and the data conversion is executed.

Instead of referring to the state table, the state of the system may be evaluated by a predetermined procedure and the data conversion method may be directly selected based on the evaluation result.

As a concrete example of switching the data conversion method depending on the state of the system, in the image display device,
It is possible to convert the data according to the number of colors that can be displayed and the resolution. For example, when the image data stored in the magnetic disk device 6 is a 24-bit color image and the number of colors that can be displayed by the image display device is an 8-bit color image, the data conversion device 4 uses the system state detection unit. The number of colors that can be displayed by the image display device is checked by, and a data conversion procedure for converting 24-bit color image data into 8-bit color image data is selected and data conversion may be performed.

As another selection method, the data conversion method can be selected according to the attribute stored in the magnetic disk device 6. As the attribute, for example, the file attribute stored in the directory or the file extension is used, or the attribute value is stored in the FAT for each block, or the magic number is stored in a few bytes at a predetermined position of the file. Is stored and these pieces of information may be used. The magnetic disk device 6 manages a page block and holds and manages these attributes. Further, the data conversion device 4 holds and manages an attribute table showing correspondence between each attribute and the data conversion method.

In the data conversion step, data conversion device 4 retrieves the attribute corresponding to the page block from the temporary storage table, refers to the attribute table to determine the data conversion method, and executes the data conversion.

For example, when there are a compressed file and a normal text file in the magnetic disk device 6, the attribute for distinguishing them is determined, so that the compressed file is expanded at the time of page-in. However, it is possible to control automatically so that the conversion is not performed in the case of a normal text file.

As still another example, it is conceivable to hold statistical information at the time of data conversion by the data conversion device 4 and select the conversion method based on that information. The data conversion device 4 holds statistical information associated with data conversion as a table. Let that table be a statistical information table. Figure 1
5 is an explanatory diagram of an example of the contents of the statistical information table.
Each row of the statistical information table represents statistical information corresponding to each conversion method. As the statistical information, for example, FIG.
As shown in FIG. 5, the average processing time for data conversion, the maximum processing time for data conversion, and the minimum processing time for data conversion can be set. Of course, the data conversion device 4 can also hold other information. The statistical information table can be stored in the magnetic disk device 6 and read into the data conversion device 4 as appropriate.

When the data conversion device 4 selects the data conversion method, the information in the statistical information table held by the data conversion device is evaluated by a predetermined evaluation procedure, and the data conversion method corresponding to the obtained result is selected. The predetermined evaluation procedure may be held by the data conversion device 4 or may be given from an application program. For example, a method of giving a pointer to the evaluation procedure as one of the arguments of the mmap function described above can be considered.

In each of the selection methods described above, the various tables arranged in the data conversion device 4 may be configured to be managed by another management device such as the pager 2. Also, some types of information, such as file attribute information,
It is also possible to provide columns in the page table for management.

Next, an application example of the virtual memory system of the present invention will be described. FIG. 16 is a block diagram of an example in which the virtual storage system of the present invention is applied to the processing of video data. In the figure, the same parts as those in FIG. Reference numeral 11 is a data processor, 12 is an output device, 13 is a line performance measuring device, and 14 is a line performance database. In this example, video data expressed at a specific frame rate is recorded as a video data file on the magnetic disk device 6, and a method of reading and transferring at a desired frame rate according to the speed of the communication line is shown. . Video data files are, for example, 3 per second
It is assumed that the video data represented by 0 frame and represented by 1 kilobyte per frame is stored in the magnetic disk device 6. The output device 12 sends video data to the serial line. The user views the video data sent from the output device 12. The line performance measuring device 13 measures the performance of the output device 12, and the measurement result is notified to the data processor 11. The line performance database 15 stores information for determining the line state based on the measurement result.

A case where the user views the video of the video data file stored in the magnetic disk device 6 via the serial line of 64 kilobits per second will be described. In this case, exactly 8 frames of video can be transferred per second.

The application opens the video file and activates the memory map system call using the first data conversion procedure as one of the arguments. As the first data conversion procedure, it is possible to specify a procedure in which video data is taken out every eight frames and written in the main storage device.

The pager controls the video data on the magnetic disk device 6 to be read into the temporary storage device 5, and the data conversion device 4 executes the first data conversion procedure to take out the video data for every 8 frames. , To the main storage device 3.

The application sequentially reads out the frames expanded in the main memory 3 frame by frame and performs the processing. At this time, since the video data expanded in the main storage device 3 has already been transferred to the main storage device 3 according to the transfer speed of the serial line, the application processes the video data independently of the transfer speed of the serial line. be able to.

Also, for example, even when only 5 frames of video can be transferred per second due to congestion of the serial line while viewing the video data, a data conversion procedure for extracting the video data every 5 frames is specified. By re-mapping, the congestion of the serial line can be dealt with.

No matter how many frames are taken out,
In addition, in order to view the video as smoothly as possible, that is, in order to determine the optimum frame rate, it may be determined after executing the performance measurement procedure for measuring the communication speed and the congestion degree of the serial line. In the example shown in FIG. 16, the line performance measuring device 13 is provided so that the communication speed and congestion degree of the serial line can be measured. Based on the measurement result by the line performance measuring device 13, the data processor 11 executes a predetermined procedure. For example, referring to the line performance database 15, the line state corresponding to the measurement result is determined, and the line state is determined. You can select and specify a suitable data conversion procedure.

FIG. 17 is a block diagram of another example in which the virtual storage system of the present invention is applied to the processing of video data.
16, those parts which are the same as those corresponding parts in FIG. 16 are designated by the same reference numerals, and a description thereof will be omitted. 15 is a data processor performance measuring device, 16
Is a magnetic disk performance measuring device, and 17 is a conversion method selecting device. In this example, in addition to the example shown in FIG. 16, a data processor performance measuring device 15 for measuring the performance of the data processor 11 and a magnetic disk performance measuring device 16 for measuring the performance of the magnetic disk device 6 are provided. The measurement results of the line performance measuring device 13, the data processor performance measuring device 15, and the magnetic disk performance measuring device 16 are input to the conversion method selection device 17. The conversion method selection device 17 determines the optimum frame rate based on the measurement results from these performance measurement devices, and selects the data conversion method for converting the video data to the frame rate. The data conversion device 4 performs data conversion according to the data conversion method selected by the conversion method selection device 17 to generate video data having an optimum frame rate.

According to this example, the optimum frame rate is determined by evaluating the performance of the data processor and the disk device in addition to the communication speed and the congestion degree of the serial line. It is possible to always perform optimal video data transmission without being affected by the access speed of the device and the congestion degree of the data processor. Of course, it can be configured to evaluate other system performance.

As described above, according to the examples shown in FIGS. 16 and 17, the video data having the optimum frame rate is already obtained when the data is transferred to the main storage device 3 according to the line status and the system status. Therefore, the application can perform processing without worrying about the frame rate, and the application can be created independently depending on the line speed, line state, system state, and the like.

FIG. 18 is a block diagram of an example in which the virtual storage system of the present invention is applied to a network. In the figure,
The same parts as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. Reference numeral 21 is a network, 22 is an auxiliary storage device, 23 is a temporary storage management device, 24 is a magnetic disk device, and 25 is a temporary storage device. In this example, the magnetic disk device 6 of FIG.
An auxiliary storage device 22 is connected to the network 21. The auxiliary storage device 22 includes a temporary storage management device 23, a magnetic disk device 24, and a temporary storage device 25. The temporary storage management device 23 manages the storage areas of the magnetic disk device 24 and the temporary storage device 25. Magnetic disk unit 2
Of course, the configuration may be such that paging is performed between the data storage device 4 and the temporary storage device 25.

As the network 21, for example, a well-known Ethernet or the like can be used. Via this network 21, temporary storage devices 5 and 25
Communicate with each other and cooperate to operate as described above.

For example, the data conversion device 4 converts the pre-conversion data in the temporary storage device 5 into, for example, a communication format, and uses the well-known network protocol, for example, TCP / IP protocol to connect the network 2 to the network 2.
Communication is performed according to 1, and the pre-conversion data is written in the temporary storage device 25.

On the contrary, the auxiliary storage device 22 communicates the pre-conversion data in the temporary storage device 25 with the network 21 using a well-known network protocol, for example, TCP / IP protocol, and temporarily stores it. It is written in the device 5 as pre-conversion data. Then, the data converter 4 restores the converted data.

In any case, instead of performing the data conversion on the data in the temporary storage device 5, the temporary storage device 2
The data conversion device 4 may be provided on the side of the auxiliary storage device 22 so that the data in the data 5 is converted. In addition, data conversion devices are arranged on both sides, and the network 21
Can be configured so that the data before conversion is only during communication. In this case, the security of data on the network 21 can be ensured by performing encryption and decryption by the data conversion device.

By using the configuration using such a network, it is possible to realize a remote file system for the magnetic disk device via the network. In addition to the auxiliary storage device 22 shown in FIG.
Auxiliary storage device, third auxiliary storage device ...
A plurality of auxiliary storage devices may communicate with each other via a network to form an auxiliary storage device group that operates in cooperation with the temporary storage device 5 and the like.

Next, an application example in which encryption and decryption are performed by the virtual storage system of the present invention will be described. As the device configuration, the configuration shown in FIG. 1 or the configuration shown in FIG. 18 can be used. As the data conversion procedure performed by the data conversion device 4, an encryption procedure for converting m blocks into n blocks or a decryption procedure for converting n blocks into m blocks is used. In particular, as the first data conversion procedure, for example, a decryption procedure based on the encryption method known by the DES algorithm,
The second data conversion procedure is a decryption procedure based on the encryption method also known by the DES algorithm.

When selecting the data conversion procedure, the application program specifies the encryption / decryption conversion method and its key information. For example, such information is designated as one of the parameters of the file open process. These parameters are interpreted by the pager 2, and the number of the conversion procedure, which is determined by two arguments that specify the conversion procedure and the argument that specifies the key information, is stored in the corresponding location of the page table.

FIG. 19 is an explanatory diagram of an example of a page table used for encryption / decryption. For registration in the page table, the number of the conversion procedure is specified by the argument specifying the conversion procedure, and the key information is stored in the key information column. When the conversion procedure is activated, the conversion procedure is started by referring to the key information column of the page table.

Alternatively, information for data conversion can be separately held and managed as, for example, a data conversion table. In this case, a column for holding the key information is provided in the entry of the data conversion table, the number of the conversion procedure is specified by the argument specifying the conversion procedure, and the key information is used when the conversion procedure is activated later. The conversion procedure may be started by referring to the key information column of.

With the above configuration, an application or user having key information can access by encrypting or decrypting data.

In this example, since the data block recorded in the magnetic disk device 6 is recorded with the information encrypted by the DES algorithm, it is preferable in terms of security management against leakage of confidential information due to the theft of the magnetic disk device. Further, in the present invention, as described above, since the area of the temporary storage device 5 can be separately configured for the pre-conversion data and the post-conversion data, it is encrypted with the page holding the decrypted data. By storing a page that holds data in a distinguishable manner and by not writing a page that holds decrypted data to the magnetic disk device 6, unencrypted data is stored in the magnetic disk device 6. You can prevent it. Therefore, it is preferable in terms of security management that confidential information is leaked by looking into the data on the magnetic disk device 6.

Further, in the configuration in which the information storage methods via the network described in FIG. 18 are combined, it is possible to prevent unencrypted data from being transferred to the remote magnetic disk device by network communication. This is preferable in terms of security management against the leakage of confidentiality caused by eavesdropping on network communication.

In this example, the application program need not include the implementation of the encryption procedure and the decryption procedure of the data to be accessed. In addition, by using a common procedure in which multiple applications are built into the system, modularization of the program can be achieved, the efficiency of application creation can be improved, and security management by careful implementation is not only possible. Regarding the above defects, it is not necessary to pay attention to each application and it is preferable in terms of management.

Furthermore, in this example, since the system encrypts / decrypts during the processing of virtual memory, the data used for encryption / decryption can be compared with the method of encryption / decryption by the user process. Concealment of resources such as temporary storage becomes easy.

FIG. 20 is a block diagram of an example in which the virtual storage system of the present invention is applied to image processing. In the figure,
The same reference numerals are given to the same portions as, and the description thereof will be omitted. Three
Reference numeral 1 is a terminal device, 32 is a terminal performance measuring device, and 33 is a conversion method selecting device. Here, a case where an application that processes an image of a certain resolution is read after an image data file of a specific resolution is recorded on the magnetic disk device 6 at a specific gradation and an output device, for example, the terminal device 3 is used.
A case of reading with a desired resolution and a desired expression gradation according to 1 will be described. The performance of the terminal device 31 is measured by the terminal performance measuring device 32, and the conversion method selection device 33 selects a data conversion procedure in the data conversion device 4 based on the measurement result. Data conversion is performed according to the selected data conversion procedure.

Hereinafter, a specific example will be described. As the image data of the image data file stored in the magnetic disk device 6, for example, it is assumed that an image having 600 pixels vertically and horizontally and having a resolution of 400 pixels per 25.4 mm is represented. Each pixel is red, blue,
It is assumed that each green is represented by 256 gradations. The name of this image data file is A. Further, the data conversion procedure prepared in the data conversion device 4 is a resolution conversion procedure. This procedure is 4 per 25.4 mm
It is assumed that there are three types of procedures for converting from a resolution of 00 pixels to an image of 75 pixels per 25.4 mm, 100 pixels per 25.4 mm, and 200 pixels per 25.4 mm.

The file names of the files holding the same image data as the file A are A # 75, A # 100, A #.
200 and A # 400. File A that holds exactly the same image data may be copied from file A, but multiple file names can be assigned to the same file using the symbolic link or hard link mechanism used in the conventional UNIX OS file system. It may be provided by giving.

When the file A # 75 is opened, a procedure for interpreting the file name is executed. For example, a data conversion procedure for converting the resolution of 400 pixels to the resolution of 75 pixels by the numerical value 75 following the symbol # in the file name. Can be specified. This specification is given as an argument of the memory map system call.

As described above, by the memory map system call, 2 is set as the conversion method in the data conversion table.
From a resolution of 400 pixels per 5.4 mm to 25.
Registered to select a data conversion procedure to convert to an image with a resolution of 75 pixels per 4 mm. Then, at the time of data transfer to the main storage device, resolution conversion is performed by the data conversion device 4. Therefore, the application does not have to be aware that the image has a resolution of 400 pixels per 25.4 mm.
It can be read as an image with pixel resolution.
The same applies to the files A # 100 and A # 200.

Next, an application for outputting the file A holding the above-mentioned image data to a terminal or printer will be described. The user opens this image file, converts it to a resolution of 75 pixels and maps it to memory for display on a display with a resolution of 75 pixels per 25.4 mm. Therefore, as the first conversion method, an image processing procedure for gradationally converting an image of 400 pixels per 25.4 mm into an image of 75 pixels may be designated. As this method, for example, as described above, the number indicating the image procedure of gradation conversion is stored in the memory
It can be issued by giving it as an argument of the map system call.

The resolution of the terminal device or the printer device which the application intends to output is determined by the terminal performance measuring device 32.
Can be obtained by Based on the obtained resolution, by the conversion method selection device 33, without the user's involvement,
An image processing procedure for gradation conversion is automatically selected.

Alternatively, the system description file holding the resolution of the terminal device or the printer device is referred to, or a procedure for inquiring to another application holding the resolution of the terminal device or the printer device is executed.
In this procedure, for example, an inquiry is made to a terminal or a printer to obtain resolution information. An image processing procedure for gradation conversion may be automatically selected based on the obtained resolution without the user's involvement and designated as an argument of the mmap system call. For example, when an application is started on a terminal device having a resolution of 75 pixels, the application communicates with the terminal device to display a file having a resolution of 400 pixels on the terminal, and the application device is a terminal device having a resolution of 75 pixels. obtain. Then from the resolution of 400 pixels to 75
The number of the data conversion procedure for converting to the pixel resolution is given as an argument of the memory map system call.

According to this example, the image data of 400 pixels per 25.4 mm on the magnetic disk device 6 is obtained by the data conversion procedure selected by the data conversion device 4.
It is converted into image data of 75 pixels per 25.4 mm and transferred to the main storage device 3. Therefore, the application that displays the image data in the main storage device 3 on the display should perform a special resolution conversion process regardless of the resolution of the image data stored in the image data file in the magnetic disk device 6. Instead, it is only necessary to output the image data mapped on the main storage device 3 to the display.

Further, the resolution of the display device is 25.
Even if the number of pixels is 100 pixels instead of 75 pixels per 4 mm, the data conversion procedure is automatically detected by the terminal performance measuring device 32 and the data conversion procedure is switched, or 25.
The image processing procedure for converting the resolution of the image of 400 pixels per 4 mm into the image of 100 pixels need only be designated as the first conversion procedure, and the application can be created independently as the resolution of the output device.

In the above example, the resolution of the image data file is constant, but a method of selecting the data conversion procedure when the resolution of the image data in the image data file is different will be described. In this case, for example, the method of selecting the data conversion procedure by the magic number described in the method of selecting the data conversion procedure described above can be used. FIG. 21 is an explanatory diagram of an example of a magic number. For example, as shown in FIG. 21, a 2-byte value representing the resolution of file data is placed at the beginning of the file as a magic number. When you open an image file,
A procedure for reading and interpreting the first 2 bytes of the file is executed, the resolution is determined, and an appropriate conversion procedure is selected.

For example, suppose that an image file is stored as an image file in which the vertical and horizontal directions are 600 pixels, the resolution is 400 pixels per 25.4 mm, and each pixel is represented by 1 byte. The name of this file is A. Also, the vertical and horizontal directions are 600 pixels each, and the resolution is
It is assumed that there are 200 pixels per 5.4 mm, and an image represented by 1 byte per pixel is stored as an image file. The name of this file is B.

The resolution conversion procedure prepared by the system is 75 pixels from the resolution of 400 pixels.
It is assumed that there are six types of procedures, that is, a procedure of converting to a resolution of pixels, 100 pixels, and 200 pixels, and a procedure of converting from a resolution of 200 pixels to a resolution of 75 pixels, 100 pixels, and 200 pixels, respectively.

Display When the display has a resolution of 75 pixels per 25.4 mm, when the image file A is opened, the magic number indicates that the resolution of the image is 400 pixels per 25.4 mm. As the procedure, the procedure of converting from the resolution of 400 pixels to the resolution of 75 pixels is selected. When the file B is opened, a procedure for converting the resolution of 200 pixels to the resolution of 75 pixels is selected based on the magic number.

Also in this case, whether the file A is opened or the file B is opened, the image data mapped in the main memory 3 is converted into the image data having the resolution of 75 pixels per 25.4 mm. Therefore, the application can perform display on, for example, a display indicator regardless of the resolution of the image data stored in the image data file.

In the above-mentioned resolution conversion example, a data conversion procedure for performing a large number of resolution conversions is prepared.
It is also possible to prepare only one or several kinds of data conversion procedures and to give the resolution of the image data in the image file and the resolution of the image data required by the application or the output device as parameters to the data conversion procedure.

In the above-mentioned example, the resolution conversion is described, but the present invention is not limited to this. For the gradation conversion and the color conversion, like the resolution, a data conversion procedure for performing a desired data conversion should be designated. Therefore, since the data is converted into the gradation and color that can be processed by the application or the gradation and color that can be expressed by the output device and transferred to the main storage device 3, the gradation and color are independent of the gradation and color. You can create applications in.

Further, even if the user does not know the resolution and gradation of the terminal device used by the user, the resolution and gradation are automatically converted, and WYSIWYG (What You
See Is What You Get) property is maintained. An application can create different resolutions, expressible gradations and colors for each image display device in a form that does not depend on the model without performing special image processing, and can improve portability.

The conversion processing of image data is performed by resolution, gradation,
In addition to conversion of colors and the like, various image processing such as coordinate conversion such as image rotation and enlargement / reduction, clipping processing of a specific area, combining processing with a specific image, compression / expansion, and the like can be performed.

In the information storage system of the present invention, since it is possible to separately manage the area holding the data before resolution conversion and the area holding the data after resolution conversion, for example, a plurality of resolutions can be simultaneously set. When converting,
Data before resolution conversion can be shared. Also,
Since the data after conversion is created by performing the conversion process from the data before conversion, the data before conversion is not paged out to the magnetic disk device 6. By adopting the paging method, the input / output of the magnetic disk device 6 is performed. Efficient resolution conversion can be achieved without depending on the speed.

Although some application examples have been described above, the present invention is not limited to these examples and can be applied to various data processing.

[0143]

As is apparent from the above description, according to the present invention, since the data conversion information is included,
According to this information, the processing executed at the time of transfer can be dynamically switched, and the data conversion can be executed at the time of paging. Therefore, it is possible to provide a highly flexible virtual storage system for a wide range of applications.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of an example of a page table.

FIG. 3 is an explanatory diagram of an outline of an operation in one embodiment of the virtual storage system of the present invention.

FIG. 4 is a flowchart illustrating a page-in operation in an embodiment of the virtual storage system of the present invention.

FIG. 5 is an explanatory diagram showing an example of a page-in operation in the embodiment of the virtual storage system of the present invention.

FIG. 6 is an explanatory diagram showing an example of a page-in operation in one embodiment of the virtual storage system of the present invention.

FIG. 7 is an explanatory diagram showing an example of a page-in operation in the embodiment of the virtual storage system of the present invention.

FIG. 8 is an explanatory diagram showing an example of a page-in operation in the embodiment of the virtual storage system of the present invention.

FIG. 9 is a flowchart illustrating a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 10 is an explanatory diagram showing an example of a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 11 is an explanatory diagram showing an example of a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 12 is an explanatory diagram showing an example of a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 13 is an explanatory diagram showing an example of a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 14 is an explanatory diagram showing an example of a page-out operation in the embodiment of the virtual storage system of the present invention.

FIG. 15 is an explanatory diagram of an example of contents of a statistical information table.

FIG. 16 is a block diagram of an example in which the virtual storage system of the present invention is applied to the processing of video data.

FIG. 17 is a block diagram of another example in which the virtual storage system of the present invention is applied to the processing of video data.

FIG. 18 is a block diagram of an example in which the virtual storage system of the present invention is applied to a network.

FIG. 19 is an explanatory diagram of an example of a page table used for encryption / decryption.

FIG. 20 is a block diagram of an example in which the virtual storage system of the present invention is applied to image processing.

FIG. 21 is an explanatory diagram of an example of a magic number.

[Explanation of symbols]

1 memory management device, 2 pager, 3 main storage device,
4 data conversion device, 5 temporary storage device, 6 magnetic disk device, 11 data processor, 12 output device,
13 line performance measuring device, 14 line performance database, 15 data processor performance measuring device, 16 magnetic disk performance measuring device, 17 conversion method selecting device, 21
Network, 22 auxiliary storage device, 23 temporary storage management device, 24 magnetic disk device, 25 temporary storage device, 31 terminal device, 32 terminal performance measuring device, 33
Conversion method selection device.

Claims (9)

[Claims] 1. In a page-type virtual storage system, a main storage device, storage management means for managing at least the main storage device, data transfer information holding means for holding information on data transfer, and information on data conversion are stored. The data conversion information holding means for holding the data, the data conversion means for performing data conversion on the transfer data, and the data transfer information held in the data transfer information holding means are referred to for data transfer in page units, and When data is transferred, it has a pager for giving a predetermined data conversion instruction to the data conversion means and a management instruction to the storage management means based on the information regarding the data conversion held in the data conversion information holding means. Virtual memory system. 2. The pager transfers data in page units between an auxiliary storage device or a temporary storage device and the main storage device, or between a paging target area and a non-paging target area in the main storage device. 2. The virtual storage system according to claim 1, wherein the data conversion means performs data conversion on the transfer data during data transfer. 3. When the pager transfers data in page units between a paging target area and a non-paging target area in the main storage device, the storage management means is held by the data conversion information holding means. 3. The virtual memory according to claim 2, wherein the virtual memory can be managed so as not to erase a predetermined page that has been paged out to a non-paging area in the main memory based on information regarding data conversion being performed. system. 4. When the pager transfers data in page units between the main storage device and the auxiliary storage device, the storage management means converts the data in the main storage device by the data conversion means. The virtual storage system according to claim 2, wherein the virtual storage system can be managed so as not to be paged out to the auxiliary storage without being interrupted. 5. The data conversion means has a plurality of data conversion processes, selects one or a plurality of data conversion processes from the plurality of data conversion processes according to an instruction from the pager, and outputs data by the pager. When transferring,
The virtual storage system according to any one of claims 1 to 4, wherein a selected data conversion process is performed on the transfer data. 6. The virtual storage system according to claim 5, wherein the data conversion process is selected based on a result of executing a predetermined procedure. 7. The virtual storage system according to claim 5, wherein the data conversion process is selected based on a parameter designated by a user. 8. The virtual storage system according to claim 5, wherein the selection of the data conversion processing is performed based on information such as a system status and page attributes. 9. The virtual storage system according to claim 1, wherein the data conversion unit can register a predetermined data conversion procedure prepared by a user in advance.