Caching system capable of supporting zero copy on the basis of flash memory array, and method

Abstract

The invention discloses a caching system capable of supporting zero copy on the basis of a flash memory array, and a method. The system comprises a main control module, a physical caching module, a read address and write address conversion module, an idle block management module, a metadata recording table and a rear side flash memory module. The method comprises the following the following steps that: receiving a command request sent from a front side, converting a logic block number in the command request into a corresponding physical block number, carrying out a Hash operation on a rear-side address in the command request to obtain a corresponding metadata address index; according to the metadata address index, inquiring a metadata state table and a metadata record chart, processing the data of a corresponding table item in the metadata record chart according to the state information of the corresponding table item of the state table, and updating the corresponding table item of the metadata state table, and updating a mapping table in the read address and write address conversion module; and returning a completion command to the front side. By use of the system, a contradiction that the read-write access size of a traditional cache and a flash memory page size are not matched is solved, meanwhile, the zero copy on a caching read-write data path is realized, an unnecessary middle copy process is eliminated, cache read-write efficiency is improved, meanwhile, erasing for Flash can be reduced, and the service life of the Flash is prolonged.

Description

technical field [0001] The invention relates to the technical field of data processing, in particular to a flash memory array-based cache system and method supporting zero copy. Background technique [0002] The solid-state storage system using NAND Flash has gradually become a new popular storage system (Solid State Disk, SSD). With the development of flash memory technology, the single page capacity of MLC gradually develops from 4KB to 8KB, 16KB, and 32KB. With the maturity of TLC technology, the single page capacity will reach 64KB, 128KB or even higher. However, the service life of Flash is limited (25nm MLC can be erased and written about 3000 times), so in order to improve the service life of Flash, the erasing and writing operations on Flash should be minimized. [0003] Zero-copy (zero-copy) technology was originally the main technology for realizing high-speed network interfaces of devices such as hosts or routers. Later, it generally refers to reducing the numb...

AI Technical Summary

Problems solved by technology

If you simply apply for the cache according to the page size, it will cause a waste of cache space, thereby reducing the cache hit rate

[0005] In addition, the cache of traditional flash memory requires two data copies when reading and writing, which reduces the access speed of the cache and affects the performance of the entire storage system.

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