Solid-state drive cache achievement method and solid-state drive

Abstract

The invention discloses a solid-state drive cache achievement method and a solid-state drive. The solid-state drive cache achievement method is characterized in that an SCM is added in the solid-state drive, a hard drive controller regards the SCM as solid-state drive cache, a host writes host data into the solid-state drive, the SCM is firstly written to achieve data cache, a renewing program is set in the background, and the renewing program renews the cached data to a NAND storage unit of the solid-state drive, and recycles the corresponding cache; regarding the SCM, when the system is power off, data in the SCM can continue to be stored. The SCM replaces partial DRAM to be regarded as data cache, a read-write speed higher than flash memory can be provided, and the SCM is cheaper than the DRAM in cost. Data can be ceaselessly stored even under the state that a power source is lost, the operation at a byte level is supported, and the safety of the data can be guaranteed on the premise that the high data accessing speed is guaranteed.

Description

technical field [0001] The invention relates to solid-state hard disk control technology, in particular to a solid-state hard disk cache realization method and the solid-state hard disk. Background technique [0002] figure 1 It is a typical NAND composition diagram: DIE, a unit that can be operated independently and concurrently; Block, a unit that can be erased independently, and the data at each physical location in it must be erased before the next write; Page, read write unit. [0003] SSD (Solid State Drive) has been widely used in various occasions, and it is gradually replacing traditional HDD storage devices. In order to obtain the maximum concurrent writing speed of NAND, it is necessary to maintain a cache of user data in the memory (DRAM), and initiate concurrent writing to NAND after sufficient data is cached, so as to obtain the highest performance. Since the memory is a volatile device after power failure, the SSD system designed based on this scheme will c...

AI Technical Summary

Problems solved by technology

Since the memory is a volatile device after power failure, the SSD system designed based on this scheme will completely lose the data in the Cache after power failure, resulting in damage to user data.

[0004] figure 2 It is a schematic diagram of using DRAM to implement caching. At present, most SSD internal user data Cache management strategies: maintain a large write Cache in the memory; the user data written by the host Host is first written into the cache DRAM, and the host is notified that the data writing is complete ; When enough data is assembled or other specific strategies are triggered, the data in the cache is written to the NAND that stores user data, and the cache is released after completion; when a power failure occurs, the cache has not been written to the NAND. Data will be lost; in system-level application scenarios, it will cause file system damage, system blue screen and other problems

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