Data storage apparatus and read/write method using unavailable page table or unavailable block table

Abstract

The present invention provides a data storage apparatus. The data storage apparatus comprises a host interface, a main control chip, one or more NAND chip used for storing data and an MRAM. The NAND chip and the MRAM are separately connected to the main control chip. The MRAM comprises a write cache or a read / write cache, and the MRAM further comprises an erasure time table and an unavailable page table, wherein the erasure time table is used for storing the number of times of erasing each block in the NAND chip, and the unavailable page table comprises a page in a bad block that appears when the NAND chip leaves a factory, a page in a bad block that appears in a subsequent read / write usage process and alternative pages of the foregoing pages. According to the data storage apparatus and the read / write method using the unavailable page table / unavailable block table, which is provided by the present invention, the MRAM comprises the write cache or the read / write cache, which not only ensures read / write performance, but also reduces the number of times of erasing the NAND and prolonging the service life of the data storage apparatus; the erasure time table and unavailable page table / unavailable block table of each block are maintained, and an NAND management technology of remote writing will not be adopted any more, and a logic address and physical address contrast table that occupies a large amount of space does not need to be stored, so that not only storage space is saved, but also complex processing is not required, thereby further improving read / write performance.

Description

technical field [0001] The invention relates to the field of data storage, in particular to a data storage device and a method for reading and writing an unavailable page table or an unavailable block table. Background technique [0002] Currently, the development of NAND flash memory technology has promoted the SSD industry. [0003] Such as figure 1 As shown, high-speed serial interfaces such as SATA, PICe and other technologies are used between the SSD and the host. Internally, it consists of a set of NAND chips for storing data, DDRDRAM (memory) for supporting calculation and caching data, and a main control chip (SSDController). NAND also stores a logical address and physical address comparison table. Sometimes a power failure protection system is also required. [0004] NAND is a storage device that reads and writes as a whole. The smallest readable unit is called a page, and the smallest erasable unit is called a block. A block is often composed of many pages. Afte...

AI Technical Summary

Problems solved by technology

However, the introduction of the write cache creates a new problem: once a power failure occurs, the content in the DRAM cache that has not been written to the NAND will be lost, causing the system to lose data or even damage the entire file system

However, this method consumes more system memory

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