Catalogue access method in DFS (distributed file system)

A technology of distributed files and access methods, which is applied in the field of organization of directory items in a distributed file system, and can solve problems such as low retrieval efficiency of directory items

Active Publication Date: 2012-03-21
DAWNING INFORMATION IND BEIJING +1
View PDF2 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The present invention aims to disclose an efficient method for organizing directory items in a distributed file system, so as to solve the prob

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Catalogue access method in DFS (distributed file system)
  • Catalogue access method in DFS (distributed file system)
  • Catalogue access method in DFS (distributed file system)

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] Below in conjunction with accompanying drawing do specific description as follows:

[0023] (1) For a single directory, all directory entries are stored in the same file, and the names of all directory entries are hashed to divide them into N subsets (in the present invention, N is selected as 1024).

[0024] (2) For each subset, stripe storage is carried out in blocks, and the storage method is as follows figure 1 . In this solution, the size of each stripe is selected to be 256K, which is consistent with the read-ahead window size of the Linux virtual file system. For each directory stripe block, memory mapping is used to map it to a virtual memory area, so that it can be accessed directly, without the need for cumbersome management structures and read and build operations.

[0025] (3) The directory entries inside each stripe block are stored in a binary tree, and its structure is shown in figure 2 . Such as figure 2 As shown, at the head of each stripe block,...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

In the invention, the content of catalogues is stored by documents, and as for the catalogue items in the catalogues, the catalogue items are divided into a plurality of subsets by hashing the titles of the catalogue items. Different subsets are stored in the catalogue documents in a striped manner, and the strip is relatively larger, so that the pre-reading function of a bottom file system can be fully utilized when a disc is read. The catalogue items in the strips of each subset are stored in a binary tree manner, so that the binary tree can be prevented from being set when initial reading is conducted. All the strips are accessed in a memory map (mmap) mode, so that expenditure caused by memory allocation and invocation of a read-write system of a system document when the disc data is accessed each time can be avoided.

Description

technical field [0001] The invention relates to an organization mode of directory items in a distributed file system, in particular to a method for accessing directories in a distributed file system. Background technique [0002] With the rapid development of network technology, various network applications have an increasing demand for storage. The storage requirements of network applications are roughly divided into two types. One is the storage requirements mainly for large files, such as video and audio network applications. This type of application is characterized by a small number of files, but the size of a single file is usually at the GB or even TB level. ;Another kind of storage requirements mainly for small files, such as online shopping malls, etc. The characteristic of this type of demand is that a single file is not large, but the number of files is huge. [0003] In order to meet storage requirements, distributed file systems are introduced into various netw...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G06F17/30
Inventor 杨浩马照云马振杰邵宗有刘新春苗艳超王勇
Owner DAWNING INFORMATION IND BEIJING
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products