Flash storage scattered writing method

Abstract

This invention relates to a dispersed read-in method for flash memories, which divides a physical block of a flash memory into a first region and a second region, and the first one is composed of multiple sub-areas and the second one is one without information for the use of replacement when reading-in, when the flash-memory reads-in information, it first of all selects a physical block in a non-preset sub-block from the first region and selects a being read-in physical block in the second region, when the read-in times of said time is the multiple of the preset value, it uses other physical blocks as the physical block of the second region then to read-in the information of the selected physical blocks in the first region to the block of the second region, thus, the selected physical blocks of the first region move to the second region and the physical blocks of the read-in information of the second region will move to the first region to scatter the read-in times of each block to prolong the life time.

Description

technical field [0001] The invention relates to a distributed writing method of a flash memory, especially a writing method capable of replacing a physical block to be written, thereby dispersing the writing times of each block to prolong the service life of the flash memory. Background technique [0002] Since its inception, flash memory (Flash) has gradually replaced EEPROM or battery-powered memory in many portable devices with its attractive characteristics such as low energy consumption, non-volatility, shock resistance, and high storage density. The storage density and transmission speed of flash memory have grown by leaps and bounds, so flash memory can replace traditional storage media such as hard disk drives in many applications, but because of the access method of flash memory (Flash), it is limited by the structure design of flash memory When reading, you can only start reading data from any address in each page with a page (Page) as a unit. When writing, you nee...

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Problems solved by technology

[0002] Since its inception, flash memory (Flash) has gradually replaced EEPROM or battery-powered memory in many portable devices with its attractive characteristics such as low energy consumption, non-volatility, shock resistance, and high storage density. The storage density and transmission speed of flash memory have grown by leaps and bounds, so flash memory can replace traditional storage media such as hard disk drives in many applications, but because of the access method of flash memory (Flash), it is limited by the structure design of flash memory When reading, you can only start reading data from any address in each page with a page (Page) as a unit. When writing, you need to erase (Block) first. Erase) the entire block can be written page by page (Page by page), so when processing data with a capacity smaller than one block, the structure of the flash memory must be limited to set the access method

[0003] The general flash memory will carry out the steps of low-level formatting, so that each physical block address (Physical Block Address) in the flash memory is written into the corresponding logical block address (Logical Block Address), so as to establish the correct logical block address The conversion correspondence table with the address of the physical segment, however, since a logical block corresponds to one or more physical blocks, if the addresses of certain logical blocks are repeatedly written in use, the physical blocks to be replaced in turn It will also be limited to a certain range, which will cause the problem of too concentrated writing area, which will easily reduce the service life of the flash memory. Please refer to Figures 5 and 6, which are block diagrams (1) and block diagrams of existing data writing methods (2) As shown in the figure, it can be clearly seen that the flash memory is divided into a first area A1 and a second area A2, the first area A1 contains a logical area of ​​data, the second area A2 is an area without data, and the second The area A2 is mainly used for writing in rotation. When the flash memory is writing data, first select the physical block A21 to be written from all the physical blocks in the second area A2, and then write the data into the physical block A21, after the data is written into the physical block A21, it is moved to the first area A1 to replace the physical block A11, and the physical block A21 is changed to a block containing data in the first area A1, and the physical block A11 Then move to the second area A2, and change to a space without data, but this method only changes the data of some blocks in the first area A1, resulting in some blocks in the first area A1 and the second area A2 The physical block A21 is written in turn, and writing data to some blocks so frequently will not only make the number of writes to each block uneven, but also make the memory management performance poor and shorten the life of the flash memory

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