KR20080111242A - Apparatus and method for virtual memory in portable communication system - Google Patents

Abstract

A virtual memory apparatus of a portable terminal and a method thereof for being used as the space of a synchronous dynamic random access memory by using a NAND flash memory are provided to solve a problem about reducing life span of the NAND flash memory in the mobile terminal. A buffer(110) includes a flush index including the information of the buffer in order to perform a virtual memory file writing process and an upload index which is buffer information of the used virtual memory file in a reading process of the virtual memory file. A memory management unit(100) sets up the virtual memory and performs the calculation of the virtual memory file by using buffer information.

Description

TECHNICAL FIELD AND METHOD OF A MEMORY OF A MOBILE TERMINAL {APPARATUS AND METHOD FOR VIRTUAL MEMORY IN PORTABLE COMMUNICATION SYSTEM}

1 is a block diagram illustrating a virtual memory system of a portable terminal according to an embodiment of the present invention;

2 is a flowchart illustrating a process of setting a virtual memory in a virtual memory system of a portable terminal according to an embodiment of the present invention;

3 is a flowchart illustrating a process of reading a virtual memory file in a portable terminal according to an embodiment of the present invention;

4 is a flowchart illustrating a process for performing a process of writing a virtual memory file in a portable terminal according to an embodiment of the present invention;

5 is a flowchart illustrating a process of terminating a virtual memory process in a portable terminal according to an exemplary embodiment of the present invention.

The present invention relates to a virtual memory device and a method of a portable terminal, and more particularly, to a device and a method for using a NAND flash memory as a space of a synchronous dynamic RAM (SDRAM). .

Prior to the following description, virtual memory refers to a method widely used to overcome the limitation of memory shortage in a limited memory by mainly using an internal hard disk as a virtual memory.

That is, the operating system of the system finds an area that is not needed right now among contents loaded in the memory, stores the contents on the hard disk, and considers the memory area where the content is located as an unused memory area. Respond to a program's memory allocation request.

In general, the virtual memory technique is used in the personal computer by using the concept of page (PAGE), and the data that is not used in consideration of the least recently used (LRU) policy among the data resident in the memory is hard It moves to virtual memory space on disk and uses swap (SWAP) to bring data into the space of synchronous dynamic RAM.

However, there is a problem in that the above-described method uses a lot of resources, and even a system such as a personal computer causes a performance degradation.

When the above virtual memory technique is applied to the portable terminal, the embedded processor including a memory management unit (MMU) may be used as a space of a synchronous dynamic RAM using a NAND flash memory. .

However, when the above-described virtual memory technique is applied to an embedded system such as a portable terminal, a bad block is generated when the processor performance limitation of the portable terminal and a large number of write operations on the NAND flash memory are performed. Due to its drawbacks, it is used for read-only purposes in consideration of NAND flash memory life.

Accordingly, there is a need for a virtual memory system for enabling the portable terminal to perform tasks such as reading and writing.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus and method for providing a virtual memory system for solving the problem of shortening the lifespan of a NAND flash memory in a portable terminal.

Another object of the present invention is to provide an apparatus and method for performing a virtual memory file writing or reading process for solving a NAND flash memory life shortening problem in a portable terminal.

According to the first aspect of the present invention for achieving the above object, the virtual memory system of the portable terminal is the upload index (Upload Index) which is the buffer information of the virtual memory file used in the process of reading the virtual memory file and the virtual memory file write The virtual memory by setting a buffer including a flush index including information of a buffer to perform a process and a virtual memory to perform a function such as a synchronous dynamic RAM using a buffer information of the NAND flash memory; And a memory management unit for processing a file to be operated.

According to a second aspect of the present invention for achieving the above objects, a virtual memory processing method of a portable terminal includes the step of setting a virtual memory file of the portable terminal, the operation of calculating the set virtual memory file It is characterized by.

Hereinafter, the operating principle of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of well-known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

In the following description, an apparatus and method of a virtual memory system for enabling a NAND flash memory to perform a function such as synchronous dynamic RAM (SDRAM) in a portable terminal will be described.

In addition, the virtual memory information defined in the following description refers to information required for reading or writing the virtual memory file.

That is, the virtual memory information may be used in a writing process such as an operation requested address value, which is buffer information of a virtual memory file used in reading the virtual memory file, and slot information (eg, slot pointer, slot number, etc.) of the loaded buffer. An upload index for recording necessary information and a flush index for recording slot information of a buffer for performing a write process are included.

1 illustrates a virtual memory system of a portable terminal according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the virtual memory system may include a memory manager 100, a memory 102, and a buffer 110. The buffers include a queue buffer 112 and a paging buffer 114. It may include.

The memory management unit (MMU) 100 controls the overall operation of the virtual memory system, and according to the present invention NAND flash memory (Nand Flash Memory) such as synchronous dynamic RAM (SDRAM) Process to set the virtual memory to perform the function.

In addition, the memory manager 100 processes the operation of the virtual memory file.

That is, when performing a virtual memory file reading process, the memory manager 100 determines that a data processing failure occurs due to data access through a virtual memory address. Check the virtual memory file corresponding to the address.

Thereafter, the memory manager 100 performs a read process on the checked virtual memory file, and processes the read-processed file to copy to the paging buffer 114.

Thereafter, the memory manager 100 processes the write information necessary for writing data to the queue buffer 112.

On the other hand, when performing the virtual memory file write process, the memory manager 100 checks the allocated slot number each time the read process is performed, and checks the buffer slot number of the virtual memory file to perform the write process If it is confirmed that the slot numbers match, the slot pointer of the buffer to perform the writing process is checked.

Thereafter, the memory manager 100 converts a data processing failure address generated during the reading of the virtual memory file into an address allocated in the reading of the virtual memory file, and writes the virtual memory file in a predetermined page unit. Perform.

The buffer 110 includes a queue buffer 112 and a paging buffer 114 composed of a plurality of slots, and temporarily store data currently being used in a portable terminal as a storage location with fast access and response speed. Accordingly, the virtual memory information required for reading or writing the virtual memory file is stored.

In detail, the queue buffer 112 of the buffer 110 may include an upload index, which is buffer information of a virtual memory file used in a process of reading a virtual memory file, and a buffer to perform the process of writing the virtual memory file. It may include a flush index including information.

Here, the upload index records information required for a writing process, such as an operation value of the requested address and slot information (eg, slot pointer, slot number, etc.) of the loaded buffer, and the flush index is a buffer for performing the writing process. Slot information can be recorded.

In addition, the paging buffer 114 stores data obtained by performing the operation of the virtual memory file, and the paging buffer 114 may be included in the synchronous dynamic RAM.

The memory unit 102 stores the basic data which is an operating system and an application program for controlling the overall operation of the portable terminal as compressed basic data in a compressed form, and also stores data (telephone number, SMS message, compressed data). Image file, video, etc.).

The memory unit 102 may include a NAND flash memory and a synchronous dynamic RAM.

The memory manager 102 may be performed by a controller (not shown) of the portable terminal. However, in the present invention, the memory manager 102 is configured to describe the functions separately. Therefore, when the actual product is implemented, all of them may be configured to be processed by the controller (not shown).

The foregoing has described a virtual memory system for allowing a NAND flash memory to perform a function such as synchronous dynamic RAM (SDRAM) in a portable terminal, and in the following description, a preferred embodiment of the present invention. A method for processing a virtual memory file using the virtual memory system according to the present invention will be described.

2 is a flowchart illustrating a process of setting a virtual memory in a virtual memory system of a portable terminal according to an exemplary embodiment of the present invention.

Referring to FIG. 2, in step 201, the virtual memory system of the portable terminal instructs the memory manager 100 to check whether a virtual memory setting event occurs to allow access to a virtual memory address.

If the virtual memory setting event does not occur, the memory manager 100 proceeds to step 211 to perform a corresponding function (eg, standby mode).

On the other hand, when it is confirmed that the virtual memory setting event occurs, the memory manager 100 proceeds to step 203 to define a virtual memory space.

In operation 205, the memory manager 100 determines whether a virtual memory file is generated.

If it is confirmed that the virtual memory file is generated, the memory manager 100 proceeds to step 207 to process the virtual memory address defined in step 203 to the address of the virtual memory file generated in step 205. .

Here, the memory manager 100 may generate the virtual memory file with a size equal to the virtual memory address space in consideration of occurrence of a bad block of the virtual memory file.

Thereafter, the memory manager 100 processes the virtual memory file to be initialized, that is, virtual memory information required for a read or write process of the virtual memory file.

Here, the virtual memory information may include an upload index, which is buffer information of a virtual memory file used in a process of reading the virtual memory file recorded in a queue buffer, and information of a buffer to perform the virtual memory file writing process. A flush index may be included.

Thereafter, the memory manager 100 ends the present algorithm.

3 is a flowchart illustrating a process of reading a virtual memory file in a portable terminal according to an exemplary embodiment of the present invention.

The above process will be described on the assumption that data processing failure occurs because data access through the virtual memory address is not a real address existing in synchronous dynamic RAM (SDRAM).

Referring to FIG. 3, the virtual memory system of the portable terminal first determines in step 301 that a data processing failure occurs in step 301. Check the address of the corresponding virtual memory file.

After that, the memory manager 100 proceeds to step 305 to open the virtual memory file corresponding to the address where the data processing failure has occurred, and proceeds to step 307 to read the virtual memory file according to a user request. Perform the process.

In this case, the process of opening the virtual memory file of step 305 is performed only for the first process in order to prevent performance degradation of the virtual memory system, and the process of reading the virtual memory file of step 307 is predefined in the virtual memory system. You can perform file read operations as much as the page size you have.

After that, the memory manager 100 stores the virtual memory file in which the read process is performed in the paging buffer 114, and then proceeds to step 311, the address requested for the operation, the pointer of the loaded buffer slot, the slot number, and the like. Write virtual memory information including the to the queue buffer 112.

Here, when data stored in the paging buffer 114 is replaced with a slot of the buffer area, the memory manager 100 may process to store new data in the paging buffer 114.

Here, the virtual memory information is information required for a writing process such as an address value requested for data operation and slot information (eg, slot pointer, slot number, etc.) of the loaded buffer. The upload index of the queue buffer 112 is uploaded. Index).

Thereafter, the memory manager 100 ends the present algorithm.

4 is a flowchart illustrating a process of writing a virtual memory file in a portable terminal according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the virtual memory system first instructs the memory manager 100 to check a slot number allocated in a process of reading a virtual memory file in step 401, and then proceeds to step 403 to queue buffer 112. Instructs to determine the slot number of the buffer to perform the writing process of the virtual memory file using the virtual memory information recorded in the flush index of the.

Herein, the virtual memory information recorded in the flush index refers to slot information of a buffer to write to paging information paged in the virtual memory file reading process.

Thereafter, the memory manager 100 proceeds to step 403 to compare whether the slot numbers identified in the process match.

If the slot numbers do not coincide with each other, the memory manager 100 ends the present algorithm.

On the other hand, if it is confirmed that the slot numbers coincide with each other, the memory manager 100 proceeds to step 407 to open the virtual memory file.

In operation 409, the memory manager 100 checks the slot pointer of the buffer to perform the writing process using the virtual memory information recorded in the flush index of the queue buffer, and proceeds to step 411. Check the address where Data Abort occurred during the file reading process.

In operation 413, the memory manager 100 converts the address from which the data processing failure has been confirmed in step 411 to an address allocated to the virtual memory file reading process.

In operation 415, the memory manager 100 performs a process of writing the virtual memory file in predefined page units.

The writing process of the virtual memory file is a writing process of writing data to the virtual memory file. After all slots are used in the queue-managed buffer, the writing process is performed in the step of replacing the slot with a new slot. ).

Thereafter, the memory manager 100 ends the present algorithm.

5 is a flowchart illustrating a process of terminating a virtual memory process in a portable terminal according to an exemplary embodiment of the present invention.

Referring to FIG. 5, the virtual memory system first instructs the memory manager 100 to check whether a portable terminal power off request is detected by a user in step 501.

If the request is not detected, the memory manager 100 proceeds to step 507 to perform a corresponding function (for example, performing a virtual memory process).

On the other hand, when detecting the request, the memory manager 100 proceeds to step 503 to close the virtual memory file, and performs a power-off process of the portable terminal.

Here, in step 503, the virtual memory file may be reused by not deleting the virtual memory file in order to save time required for generating the virtual memory file.

Thereafter, the memory manager 100 ends the present algorithm.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

As described above, the virtual memory system according to the present invention may be used to read or write the virtual memory file. In addition, it is possible to solve the problem of shortening the lifespan of NAND flash memory caused by the virtual memory file writing process, which is a problem of the conventional virtual memory system.

Claims (16)

In the virtual memory system of a portable terminal, A buffer including an upload index, which is buffer information of the virtual memory file used during the reading of the virtual memory file, and a flush index including information of a buffer to perform the virtual memory file writing process; And a memory manager configured to process a virtual memory file by setting a virtual memory to perform a function such as a synchronous dynamic RAM using the information of the buffer. The method of claim 1, The upload index records information required for a writing process, such as an operation value of a requested address and slot information of a loaded buffer (eg, a slot pointer, a slot number, etc.), and the flush index stores slot information of a buffer to perform a writing process. Virtual memory system, characterized in that the recording. The method of claim 1, The memory manager, The virtual memory system of claim 1, wherein a virtual memory file is created by defining an arbitrary virtual memory space, and the virtual memory is configured by mapping an address of the virtual memory space and an address of the virtual memory file. The method of claim 3, wherein The memory manager, And after completing the virtual memory setting, initialize the information of the flush index and the upload index of the buffer. The method of claim 4, wherein The memory manager, When data processing failure by accessing the virtual memory address occurs, the virtual memory file may be opened by checking the address of the virtual memory file corresponding to the address where the data processing failure occurs, and then may be processed to perform a data reading process. Virtual memory system, characterized in that. The method of claim 5, The memory manager, And after performing the data read process, process to store the data that has performed the data read process in a buffer. The method of claim 6, The memory manager, When checking the virtual memory file of the slot number of the buffer to perform the same write process as the slot number of the allocated buffer when performing the virtual memory file read process, it is possible to process to perform the write process for the checked virtual memory file Virtual memory system characterized by. The method of claim 7, wherein The memory manager, After checking the virtual memory file, the controller checks the slot pointer of the buffer to perform the write process and the address where the data processing failure has occurred, converts the address where the data processing failure has occurred to the address allocated in the data reading process, and then A virtual memory system characterized by being capable of processing a virtual memory write process. The method of claim 8, The memory manager, And detecting a power off request of the portable terminal, performing processing to perform power off of the portable terminal without deleting the virtual memory file. In the virtual memory processing method of a portable terminal, Setting a virtual memory file of the portable terminal; And computing the set virtual memory file. The method of claim 10, Setting the virtual memory file of the portable terminal, Defining an arbitrary virtual memory space, Mapping the address of the virtual memory space defined above with the address of the virtual memory file; The process of initializing a flush index including an upload index, which is buffer information of the virtual memory file used in the reading of the virtual memory file, and information of a buffer to perform the writing process of the virtual memory file, is further performed. Method which can include. The method of claim 11, The upload index records information required for a writing process, such as an operation value of a requested address and slot information of a loaded buffer (eg, a slot pointer, a slot number, etc.), and the flush index stores slot information of a buffer to perform a writing process. How can be recorded. The method of claim 11, Computing the set virtual memory file, And reading the virtual memory file, writing the virtual memory file, and terminating the virtual memory file. The method of claim 13, The virtual memory file reading process, When a data processing failure occurs due to a virtual memory address access, checking the address of the virtual memory file corresponding to the address where the data processing failure occurs and opening the virtual memory file; Performing a data reading process for the opened virtual memory file; And after the data reading process, storing the data on which the data reading process is performed in a buffer. The method of claim 13, The virtual memory file writing process, Checking the virtual memory file of the slot number of the buffer to perform the same write process as the slot number of the allocated buffer when the virtual memory file reading process is performed; After checking the virtual memory file, checking a slot pointer of a buffer to perform a write process and an address where a data processing failure occurs; And converting the address where the data processing failure occurs into an address allocated in the data reading process and then writing the virtual memory. The method of claim 13, The virtual memory file termination process, And detecting a power off request of the portable terminal, performing power off of the portable terminal without deleting the virtual memory file.

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