Read and write optimization dispatching method in solid-state disc system

Abstract

The invention discloses a method for improving the solid-state disc read performance. The method comprises the steps of setting the write delay upper limit; creating a prefetching queue for storing a request from an upper layer file system; obtaining information of each request in the prefetching queue, wherein the information includes the request type, the request generating time, the required execution time, the required queue waiting time and the request target address. The read requests just reaching the prefetching queue are forwards moved step by step; the improvement of the read performance is realized through preferentially executing the read request. In the dispatching process, the write delay upper limit, the read and write correlation and the relative position relationship among the same type requests are simultaneously considered, so that the normal execution of the write request, the data correctness and the fairness among the same type requests are ensured. Compared with the effect before the dispatching, the method has the advantages that 70 percent and 40 percent of maximum read delay and average read delay can be reduced, so that the read performance of the solid-state disc system is effectively improved.

Description

technical field [0001] The invention belongs to the field of computer storage, and more specifically relates to a read-write optimization scheduling method in a solid-state disk system. Background technique [0002] Solid State Disk (SSD) based on NAND flash memory (Flash) has many excellent characteristics such as non-volatility, low energy consumption, high performance, etc., so it is widely used in data centers, cloud computing, online transaction and other scenarios . Compared with traditional mechanical hard disks, NAND flash-based SSDs are not limited by the speed of mechanical parts, so they can provide higher I / O performance and are expected to alleviate I / O in many important data-intensive applications. O bottleneck. [0003] Currently, in SSDs using NAND flash, there are some read and write issues: once a write request is issued to the flash media, subsequent read requests within the same target address die must wait until the time-consuming write operation is co...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the above defects or improvement needs of the prior art, the present invention provides a read-write optimization scheduling method in a solid-state disk system, the purpose of which is to effectively improve the read performance of the solid-state disk system by dynamically adjusting the priority sequence of read-write requests , so as to solve the existing technical problems in the existing solid-state disks that the read request is blocked by the write request because the read operation speed is much faster than the write operation speed, resulting in a large read delay and poor read performance

Images