Address mapping method for flash translation layer of solid state drive

Abstract

The invention discloses an address mapping method for a flash translation layer of a solid state drive. The method comprises the following steps of (1) establishing a cached mapping table, a cached split table, a cached translation table and a global translation directory in an SRAM (static random access memory) in advance; (2) receiving an IO (input/output) request, turning to a step (3) if the IO request is a write request, otherwise turning to a step (4); (3) preferentially and sequentially searching the tables in the SRAM for the hit condition of the current IO request, finishing write operation according to hit mapping information, and caching the mapping information according to a hit type and a threshold value; (4) preferentially searching the tables in the SRAM for the hit condition of the current IO request, and finishing read operation according to the hit mapping information in the SRAM. The method has the advantages that the random write performance of the solid state drive can be improved, the service life of the solid state drive can be prolonged, the efficiency of the flash translation layer is high, the hit ratio of address mapping information in the SRAM is high, and less additional read-write operation between the SRAM and the solid state drive Flash is realized.

Description

technical field [0001] The invention relates to the technical field of solid-state disk storage, in particular to an address mapping method in a flash memory translation layer of a solid-state disk. Background technique [0002] NAND Flash-based Solid State Drive (SSD) is a non-volatile computer storage device, which can effectively improve the performance of the storage system by virtue of its low latency, low power consumption, high reliability and other advantages. In the field of enterprise and consumer storage, solid-state disks are gradually replacing traditional mechanical hard disks, and the development of high-performance solid-state disk systems has become a research hotspot in the current storage field. [0003] NAND Flash has three basic operations of reading, writing, and erasing, and its main features are described as follows: [0004] 1. Erase before write mechanism, that is, when rewriting new data to a data block that has already been written, NAND Flash ca...

AI Technical Summary

Problems solved by technology

[0004]1. Erase before write mechanism, that is, when rewriting new data to a data block that has already been written, NAND Flash cannot directly update the original data block like a disk , but the data block needs to be erased and then rewritten with new data

[0005]2. The number of erasing of a single storage unit is limited, that is, the number of times of erasing each data block (Block) in NAND Flash is limited. After the number of times, the integrity and correctness of the data stored in the data block cannot be guaranteed

Therefore, according to the characteristics of NAND Flash, how to effectively use the principle of time locality and space locality of the load to improve the hit rate of page mapping information in the SRAM cache and finally improve the efficiency of the flash conversion layer has become a key technology to be solved urgently Problem, there is no effective design method to improve the efficiency of the flash translation layer by synergistically using the principle of load time locality and space locality in the existing technology

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