The Dynamic Regulation of the Idex Structure Implementation over Flash Memory Storages
Keywords: Flash Memory, Index Structure, Embedded Systems, Dynamic Regulation, Prototype
1. Introduction
Since many queries retrieve only a proportion of the records, database system needs an index structure to help retrieving data records quickly.
//先说B树流行。
The B-tree index structure is the widely used in traditional DBMS. In view of it can maintain data efficiently when insertion and deletion occurred. However the B-tree index structure is not suited to spatial data, because the search structure of spatial data is multi-dimensional.
//引入R-tree
Guttman introduced the concept of R-tree in 1984, and many variant has been proposed since then. R-tree is tree index structures that is similar to B-tree, but is used for the access of a large collection of spatial data.
//再引入spatial data.
Spatial data is also known as gerography data that identifies the geographic location of features and boundaries on Earth. In generally, spatial data is stored as coordinates and topology and it can be mapped. Spatial data is often accessed, manipulated and analyzed through GIS(Geographic Information System).
//解释一下下GIS
GISs are used to gather manipulate and produce information related to the surface of the Earth.
GISs play an important role in nearly all fields. For example, agriculture, transportation, water conservancy, military affairs, telecast, police and be closed to our life.
and GISs are applied to hand-held devices.
//另外。。闪存在替代传统的存储设备。
On the other hand, flash memory has been gradually edged out traditional storage systems. The examples are such as mobile phones, PDAs, digital cameras, SSD(solid state disk).
//DBMS的索引在FM上不能获得与在磁盘上一样的效果。 因为FM的固有特性，如：不能覆写，读写不均衡。。。
By reason of some physical characteristics of flash memory, the implementation of index mechanism ? over these storage systems does not as well as that over disks.
//previous works 较好地解决了由闪存特性带来的问题，但是没有考虑道现实应用中的负载情况，
//小结 INTRODUCTION
In this paper, we propose an efficient indexing strategy which equipped with a dynamic regulation algorithm for getting better performance. We show that the proposed method could nicely improve the system performance under heavy workload of both write oriented and read oriented. The rest of this paper is organized as follows: In section 2, we review the background and related works. Section 3 presents the motivation. In section 4, we illustrate the dynamic regulation algorithm. Section 5 reports the experimental results. In finally we conclud this paper in section 6.
2. Background
In this section we will take a look at the characteristics of flash memory and the related works.
2.1 Flash Memory
//先写闪存的优点
//再写闪存不利的地方（一些固有特性）
2.2 Related Works
//
Disk-like R-tree Implementation
Wu's Mechanism
3. Motivation PRODLEM DEFINITION (problem specification)
//前工的不足，未考虑实际工作负载。因此，我们提出了一个DYNAMIC REGULATION 策略？ 原型 prototype
Wu's mechanism does a good job on writing overloaded applications. Disk-like R-tree implementation is propitious to reading overloaded applications.
4. Design and Implementation of the Dynamic Regulation Algorithm
In this section, we realize the dynamic regulation algorithm for the R-tree implementation over flash memory storage systems with a major objactive to coordinate the movements of above two methods.
5. Performance Analysis
6. Conclusion
References