Abrasion balance method for hybrid SSDs and SSD

Abstract

The invention discloses an abrasion balance method for hybrid SSDs and a solid-state disk. The abrasion balance method for hybrid SSDs is characterized by comprising abrasion balance in an SLC area, abrasion balance in am MLC area and abrasion balance between the areas, wherein the abrasion balance in the SLC area is taking the SLC area as a circulation queue; the abrasion balance in the MLC areais carrying out an erasing frequency of each block and preferentially selecting the blocks with low erasing frequencies to store data; the abrasion balance between the areas is dividing data in an SLCinto cold data and hot data according to a hot data recognition threshold value and migrating the cold data from the SLC area to the MLC area; and the hot data recognition threshold value is dynamically determined according to an abrasion speed. According to the method, the advantages such as high reading performance and high erasing frequency of SLC are utilized to store the hot data, and the MLC with large capacity is utilized to store the cold data, so that the compromise of cost, capacity, service life and performance is achieved. Through dynamically adjusting the hot data threshold value, the probability of writing the cold data into the SLC and the probability of writing the hot data into the MLC are reduced, and the data size migrated from the SLC to the MLC is reduced.

Description

technical field [0001] The invention relates to solid state hard disk control technology, in particular to a hybrid SSD wear leveling method and the SSD. Background technique [0002] At present, as solid state disk SSD (solid state disk) shows better characteristics than traditional mechanical hard disk, SSD has the advantages of high read and write performance, low power consumption, small size, etc., and has gradually replaced mechanical hard disk in many fields. [0003] With the development of NAND flash technology, SSD has changed from using SLC (single level cell) to using MLC (triple level cell). If all the blocks in the MLC granule are used as MLC, it will cause the disadvantages of relatively high cost and short life of the SSD. It has become a trend to convert some blocks in the MLC granule into SLC and some into MLC. Since the erasing and writing life of each block of the MLC type is limited, in order to improve its overall service life, it must be wear-leveled,...

AI Technical Summary

Problems solved by technology

On the one hand, the existing MLCSSD can extend the time that hot data stays in the SLC and improve the performance of the initial stage of SSD use; on the other hand, this mechanism increases the number of data migrations inside the SLC, increasing the garbage collection overhead and wear of the SLC. sometimes the gain outweighs the gain

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