Data page caching method for file system of solid-state hard disc

Abstract

The invention discloses a data page caching method for a file system of a solid-state hard disc, which comprises the following implementation steps of: (1) establishing a buffer link list used for caching data pages in a high-speed cache; (2) caching the data pages read in the solid-state hard disc in the buffer link list for access, classifying the data pages in the buffer link list into cold clean pages, hot clean pages, cold dirty pages and hot dirty pages in real time according to the access states and write access states of the data pages; (3) firstly searching a data page as a page to be replaced in the buffer link list according to the priority of the cold clean pages, the hot clean pages, the cold dirty pages and the hot dirty pages, and replacing the page to be replaced with a new data page read from the solid-state hard disc when a free space does not exist in the buffer link list. In the invention, the characteristics of the solid-state hard disc can be sufficiently utilized, the performance bottlenecks of the external storage can be effectively relieved, and the storage processing performance of the system can be improved; moreover, the data page caching method has the advantages of good I/O (Input/Output) performance, low replacement cost for cached pages, low expense and high hit rate.

Description

technical field [0001] The invention relates to a file system cache mechanism, in particular to a file system data page cache management method for solid-state hard disks. Background technique [0002] The performance of current processors has been improving rapidly in accordance with Moore's Law. Relatively speaking, the performance of storage systems based on mechanical disks has improved much more slowly. The gap between computing performance and storage performance is getting wider and wider. The I / O O performance bottlenecks are increasingly prominent. As the current mainstream external storage device, the disk is a bottleneck to improve the performance of the entire computer system, because its read and write access speed is generally three orders of magnitude lower than that of the memory, and reading data on the disk will affect the operation of the entire application speed. At present, Flash-based solid-state drives have a lot of room for improvement in I / O perfor...

AI Technical Summary

Problems solved by technology

[0007] However, in the Flash storage system, the cost of reading and writing is completely asymmetric, and the access time of writing is generally more than 10 times that of reading. However, the above methods do not consider the asymmetry of reading and writing of SSDs, and cannot take advantage of the characteristics of SSDs. The advantages of software-managed cache cannot be effectively utilized, and the cache utilization rate is not high, which cannot well alleviate the storage I / O performance bottleneck

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