A read cache management method and device based on a solid state disk

Abstract

The embodiment of the present invention discloses an SSD-based read cache management method. The solid-state disk SSD includes a first queue and a second queue. The method includes: receiving a read request, and judging whether the read request hits the first Queue and the second queue; if both are not hit, select and delete the eliminated data block in the first queue according to the cache replacement algorithm; if the eliminated data block is in a stored state, replace the eliminated data block Inserting into the second queue; determining the target data block corresponding to the read request from the lower-level storage medium, and inserting the target data block into the first queue; wherein, the target data block is in an unstored state. The embodiment of the invention also discloses an SSD-based cache management device. By adopting the invention, the hit rate of the SSD can be improved, the amount of data written in the SSD can be reduced and the service life of the SSD can be prolonged.

Description

technical field [0001] The present invention relates to the field of computers, in particular to a solid state disk-based read cache management method and device. Background technique [0002] At present, in order to improve the input / output performance of the disk system, such as reducing the request response time and increasing the throughput rate, in most storage systems, caching technology is used in the upper layer of the disk system to meet the performance improvement requirements. [0003] In traditional storage systems, database systems generally use DRAM (Dynamic Random Access Memory, Dynamic Random Access Memory) as the cache medium. DRAM has the advantages of read-write balance and write durability. It does not need to consider the amount of DRAM writes. Frequently write data into DRAM. [0004] In order to reduce the cost of cache media, SSDs (Solid State Drives, solid state drives) are used as cache media in more and more storage systems. SSDs have the advantag...

AI Technical Summary

Problems solved by technology

[0004] In order to reduce the cost of cache media, SSDs (Solid State Drives, solid state drives) are used as cache media in more and more storage systems. SSDs have the advantages of larger capacity, lower cost and non-volatility, but SSDs have the advantages of erasable Write limit problem

When using the traditional cache replacement algorithm (such as LRU, etc.) to manage SSDs, due to the lack of cache media to drive data updates, when new read requests miss, data blocks in the SSD will be deleted. If new read requests continue to miss , data blocks in the SSD will be continuously kicked out, and the residence time of the data blocks in the SSD will be very short. However, these kicked out data blocks may be rewritten to the SSD after a certain period of time, such frequent data Erasing and writing operations will reduce the service life of SSDs and increase costs and maintenance difficulties

Images