Method for prolonging service life of solid-state disk

Abstract

The invention discloses a method for prolonging the service life of a solid-state disk, which comprises the following steps of: (1) adding a write request into a write request queue in a buffer area of a solid-state disk; (2) selecting a data page in the write request as a sampling page; (3) calculating the fingerprint of the sampling page and also comparing with fingerprints in a fingerprint library so as to carry out matching; (4) if no matching fingerprint is found, writing the rest data pages in the sampling page and the request into a flash memory of the solid-state disk directly; and (5) if a matching fingerprint exists, carrying out fingerprint calculation on each of the rest pages respectively and also comparing with the fingerprints in the fingerprint library respectively so as to carry out matching: updating a corresponding mapping table directly for the data page in which the matching fingerprint is found and writing the data page in which the matching fingerprint is found into the solid-state disk. According to the method for prolonging the service life of the solid-state disk, the actual physical occupation of data in the solid-state disk on the flash memory is reduced, the redundant space of a system is indirectly increased, and the frequency of the garbage recovering operation of the system is reduced, so that the service life of the solid-state disk is enhanced.

Description

Technical field [0001] The invention belongs to the technical field of computer storage, and particularly relates to a method for prolonging the service life of a solid state disk. Background technique [0002] Memory is a very important part of computer system. Flash memory (FLASH), as a kind of erasable non-volatile semiconductor memory, has been very popular in the field of embedded devices due to its advantages of high storage density, low power consumption, no loss of data after power failure, and good shock resistance. Flash-based solid state memory (also called solid state disk, SSD Solid State Disk) has obvious advantages over traditional hard disks in terms of storage performance, power consumption, shock resistance and drop resistance, and more and more are used to partially or completely replace traditional hard disks To improve the performance of the storage system. However, its reliability and service life issues have become one of the main constraints for the rapi...

AI Technical Summary

Problems solved by technology

However, its reliability and service life have become one of the main constraints for the rapid and large-scale commercialization of solid-state disks.

[0003] At present, there are two main factors hindering the large-scale commercial application of solid-state disks. First, the number of erasing and writing of flash memory is limited. Since the flash memory medium stores information by injecting and erasing gate charges, due to the manufacturing process, this repeated injection and writing After erasing reaches a certain number of times, its work becomes unstable and cannot continue to be used to store data

2. Price. At present, the price per unit storage space of solid-state disk is about an order of magnitude higher than that of traditional hard disk. With the improvement of manufacturing technology and the application of multi-level storage technology (MLC, Multi-Level Cell), the price will gradually increase. decline

The flash memory operation mainly has the following three characteristics: 1. It cannot be overwritten directly, and each physical page must be erased before writing

2. It must be written sequentially, and the pages in each block must be written sequentially, otherwise the stored data will be unstable

3. The number of erasing and writing is limited, and the number of writing to each storage unit is about 10,000 to 100,000 times (for single-layer storage, SLC)

[0006] The method of improving the service life of mainstream solid-state disk products in the current market is mainly realized through wear leveling technology. It does not take into account that by reducing the actual data writing to the solid-state disk, indirectly increasing the redundant space in the solid-state disk to improve the solid-state disk service life

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