De-fragmentation method and system

Abstract

The invention provides a fragmentization removal method. The method comprises the following steps of firstly determining the expected read / write bandwidth of a data object of each access operation in an access predicted sequence, wherein the expected read / write bandwidth is fitted bandwidth obtained by taking data object length and access skip step length which correspond to the access operation as variables on the basis of a fitted bandwidth function, and then, writing the data objects of continuous multiple access operations in a new continuous storage space in sequence from a certain access operation in the access predicted sequence if the continuous multiple access operations exceed a scheduled number and the expected read / write bandwidth of the data object of each access operation is smaller than a bandwidth threshold value. According to the method, fragmentization data can be more accurately judged, and under the condition that little influence is generated on the current system performance, the read performance is improved. The method is better in adaptability in a changing environment.

Description

technical field [0001] The invention belongs to the field of computer storage, in particular to a method for processing data fragments. Background technique [0002] Fragmentation means that logically relatively continuous file data is stored in the storage medium, and its storage location becomes relatively scattered, which brings a large number of random read and write operations during data access. For the current mainstream disk-based storage systems, fragmentation will lead to a continuous decline in read / write bandwidth. Therefore, a de-fragmentation method is needed to reduce the impact of fragmentation and reduce random read and write access. [0003] Existing de-fragmentation methods usually input an access prediction sequence, identify fragmented data according to the access prediction sequence, and write the fragmented data into a new storage area, so as to achieve the purpose of de-fragmentation. The access prediction sequence is a prediction of the most likely ...

AI Technical Summary

Problems solved by technology

[0004] In the process of de-fragmentation, there are two main problems to be solved: (1) What kind of data object is fragmented data, that is, if the current storage system is accessed according to the access prediction sequence, which data object access will cause read / write bandwidth There are more declines; (2) which data should be written to the new storage location, so as to reduce the future random read and write access while affecting the current performance of the system as little as possible

The main problems in the existing de-fragmentation methods are as follows: first, the judgment of fragmented data is not accurate enough to effectively improve performance; second, in the process of de-fragmentation, too much data needs to be moved, Causes a noticeable drop in system performance during operation

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