RAID strip reconstruction method and solid state disk

Abstract

The invention discloses an RAID stripe reconstruction method applied to a solid state disk. The method is used for recombining physical block groups of an RAID memory array to form a new RAID stripe.The method comprises the steps of S1, detecting original error rates of physical blocks and updating and recording the original error rates in a block state table; S2, according to the original errorrates in the block state table, obtaining weak block information; S3, obtaining a weak block quantity through the block state table, and performing stripe organization for the physical blocks; and S4,performing block internal stripe organization in a staggered way for LSB pages and MSB pages of the physical blocks in a same RAID stripe. According to the RAID stripe reconstruction method, dynamicadjustment of the RAID stripe of the solid state disk is realized; data loss is avoided; storage space waste is avoided; the reliability of the solid state disk is improved; and the service life of the solid state disk is prolonged. Meanwhile, the invention furthermore discloses the solid state disk. The solid state disk comprises the RAID memory array and a controller used for performing adaptiveadjustment on the RAID memory array and managing data stored in the array.

Description

technical field [0001] The invention relates to the technical field of electronic storage, in particular to a RAID stripe rebuilding method and a solid state disk. Background technique [0002] Because of its high performance, low energy consumption, and good shock resistance, solid-state disks have been widely used in server systems as a viable substitute for disks. With the progress of flash memory technology, especially the development from SLC (Single-LevelCell) technology to MLC (Multi-LevelCell) technology and flash memory process technology, the capacity of flash memory is increasing day by day. However, the endurance of the physical blocks of flash memory is greatly reduced, and the reliability is significantly reduced. In order to ensure data consistency, manufacturers of solid-state disks use a Redundant Array of Independent Hard Disks (RAID) mechanism to enhance the reliability of solid-state disks. [0003] One of the functions to be realized by RAID is to stri...

AI Technical Summary

Problems solved by technology

However, life-aware RAID ignores the difference in media wear resistance (physical block level and flash page level) due to the manufacturing process, and uses the number of programming / erasing as the only indicator of the degree of wear to adjust the RAID strength. The space capacity is sacrificed, but the RAID strength adjustment still cannot meet the reliability requirements

[0008] On the one hand, the difference between wear resistance at the physical block level is ignored: when two or more physical blocks with higher raw BER are in the same stripe, the increase in stripe reliability cannot offset the physical On the other hand, ignoring the difference between the wear resistance of the flash memory page level: the life-aware RAID divides the LSB page and the MSB page into RAID stripes, so that the entire MSB stripe The degree of wear is much higher than that of LSB stripes, and because the maximum wear of the physical block flash page determines the wear of the physical block, when a physical block is unavailable, the LSB page in the physical block can still be used, thus bringing space waste

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