Statistical method and device of file prediction accuracy

Abstract

The invention provides a statistical method and a device of file prediction accuracy. The method comprises the following steps of: configuring a first statistic chain and a second statistic chain, wherein the first statistic chain and the second statistic chain have the same statistical period, and the starting time of the first statistic chain differs by half of the statistical period from that of the second statistic chain; controlling the first statistic chain and the second statistic chain to start from respective starting time, and counting the result of candidate prediction in the firsthalf period of the statistical period; and continuously counting the result of the candidate prediction in the second half statistical period, and calculating and outputting the accuracy of the candidate prediction according to the currently counted results of the candidate prediction in the period. The method not only can reduce the occasional undulatory property of the prediction to the lowest point, but also can ensure the continuity of performance evaluation output.

Description

technical field [0001] The invention relates to a file system, a file prefetching algorithm, and a file access behavior modeling and quantitative analysis method. Background technique [0002] Due to the limitation of mechanical characteristics of large data volume storage devices such as tapes and disks in computer storage systems, there is limited room for improving the data transmission rate. Therefore, the access speed gap between high-speed access devices (such as memory) and low-speed access devices (such as disks and tapes) is getting bigger and bigger. [0003] Generally speaking, the access speed of the disk limits the improvement of the overall performance of the computer to a great extent. But with the emergence of caching technology, this situation has been changed. After the data required by the system is loaded from the disk into the memory, it can reside in the memory for a long time. Subsequent accesses to the same data can be fetched directly from memory ...

AI Technical Summary

Problems solved by technology

[0008] The applicant, through in-depth research, noted that the figure 1 The division and processing method of the file pre-reading statistical cycle shown, in the first half cycle of a cycle will not be able to give P AB the correct probability statistic, and, in the latter half of the period, the P AB The correct probability statistics value is a statistical value within a period. Due to the temporal locality of file access, long-term statistical information cannot effectively reflect and estimate the current accuracy of a certain prediction.

Of course, statistical information with too short a time cannot effectively reflect the stable accuracy of a forecast

Images