Abrasion balancing method for TLC-type SSDs and SSD

Abstract

The invention discloses an abrasion balancing method for TLC-type SSDs and an SSD. The abrasion balancing method is characterized by comprising abrasion balancing in an SLC area, abrasion balancing ina TLC area and abrasion balancing between the areas, wherein the abrasion balancing in the SLC area is taking the SLC area as a circular queue; the abrasion balancing in the TLC area is carrying outstatistical analysis on an erasing frequency of each block and selecting the blocks with low erasing frequencies for storing data; the abrasion balancing between the areas is dividing data in the SLCinto cold data and hot data according to a hot data recognition threshold value, migrating the cold data from the SLC area to the TLC area; and the hot data recognition threshold value is dynamicallydetermined according to an abrasion speed. The advantages of being high in reading / writing performance and high in erasing frequency of the SLC are utilized to store the hot data, the large-capacity TLC is utilized to store the cold data, so that compromise of cost, capacity, life and performance is achieved. Through dynamically adjusting the hot data recognition threshold value, the probability of writing the cold data into the SLC and writing the hot data into the TLC is reduced, so that the size of data migrated from the SLC to the TLC is reduced.

Description

technical field [0001] The invention relates to a solid state hard disk control technology, in particular to a wear leveling method for a TLC type SSD 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 TLC (triple level cell). If only all the blocks in the TLC granule are used as TLC, 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 TLC granule into SLC and some into TLC. Since the erasing and writing life of each block of the TLC type is limited, in order to improve its overall service life, wear leve...

AI Technical Summary

Problems solved by technology

On the one hand, the existing TLCSSD 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

Images