Cache system of Not AND (NAND) flash memory and cache method

Abstract

The invention discloses a cache system of a Not AND (NAND) flash memory, comprising a two-level Hash storage module 101, a read-write interface module 104, a page data cache organization module 102 and a block data cache organization module 103, wherein the page data cache organization module 102 and the block data cache organization module 103 are both connected with the two-level Hash storage module 101 and the read-write interface module 104; the two-level Hash storage module 101 is used for recording data stored in the cache; the page data cache organization module 102 is used for organizing a page data cache queue in the cache; the block data cache organization module 103 is used for organizing a block data cache queue in the cache; and the page data cache organization module 102 and the block data cache organization module 103 read and write the data in a flash memory by the read-write interface module 104. By the system and the method of the invention, the adaptability and availability of the cache system on a file system are strengthened.

Description

technical field [0001] The invention relates to the technical field of computer storage, in particular to a cache system and a cache method of a NAND flash memory. Background technique [0002] Today, NAND (Not AND) flash memory has become the main storage medium of mobile devices. It has the advantages of random access, high throughput, low energy consumption, strong shock resistance, and small size. Therefore, in the field of personal computer and server storage, it is likely to become the main medium to replace disk as secondary storage. Nevertheless, NAND flash memory has three main disadvantages: (1) it cannot rewrite data in place; (2) it takes a long time to write data, and it takes a relatively long time to write data before rewriting data. Erase operation; (3) The erasure times of a storage unit of a flash memory are limited, so the erase operation will affect its service life. These three major shortcomings all need to be reasonably resolved in a practical NAND ...

AI Technical Summary

Problems solved by technology

Nevertheless, NAND flash memory has three main disadvantages: (1) it cannot rewrite data in place; (2) it takes a long time to write data, and it takes a relatively long time to write data before rewriting data. Erase operation; (3) The erasing times of a flash storage unit are limited, so the erasing operation will affect its service life

They can only adapt to a small part of the access type, such as only suitable for random access type or only suitable for continuous access type

However, the NAND flash memory storage system cannot organize and process page data and block data in a unified manner, and cannot adapt to the mixed access mode of random access and continuous access in practice. The adaptability and availability of the flash memory cache system to the file system are relatively weak

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