The Application And Implement Of Load Banlancing Technology In Database Cluster System

With the development of database technology and the emergence of a variety of database products, database systems in all walks of life and many areas have a wide range of applications, and with the application requirements increasing continuously, more and more users want to access and process data from multiple databases transparently. At the same time, the rapid development of e-commerce and information technology have overwhelmed database management system (DBMS), to link these databases organically, manage and coordinate them unitively will not only improve the performance of the database, but also enhance the availability of the database. As to these databases linked by a series of network connections, they must be able to handle a large number of users in real-time request, and to provide high-quality services to customers. But how can we improve the network of heterogeneous database linking the response speed, stability and scalability, and protection of the initial hardware investment; how can we avoid the impact of a large number of requests on the system? Load-balancing technology has provided us with a way to its distribution between the back-end database client request, in order to reduce system bottlenecks, and enhance response capability of the system.This article is based on the load balancing middleware technology, using three-tier architecture. The middleware layer is responsible for transmitting client requests to the most appropriate database according to the database load and load-balancing strategy. Load Balancer uses Java language, in the function of completing the collection of load information, decision-making load, load placement, supporting decision-making load balancing deployed by different databases, and supporting different dynamic modules of load balancing algorithm to add or withdraw.This paper first introduces the database clusters, database clusters and the state of study, and then Middleware of the system and its load balancing architecture. It studies the traditional load balancing architecture and composition, analyzes the advantages and disadvantages of centralized and distributed load balancing strategy, and puts forward the use of application server technology with the reverse proxy technology, scalable load balancing centralized architecture, whose focus is to deploy customized database and algorithms of different decision-making module on the needs of users through the configuration files to achieve the scalability and flexibility of the load balancing. At the same time , there is an analysis of data distribution on the impact of load balancing and a deployment of the database based on RAID technology .Then the information strategy of load balancing algorithm is studied, and the database object queue of the system is taken as an indicator of load balancing under the premise of object-oriented technology used, Otherwise, this paper studies the dynamic and static characteristics of the strategy, brings up different algorithm strategies for the deployment of different databases, and centralized dynamic strategy based on the smallest waiting queue algorithm. Finally, the above-mentioned research and design are to be achieved, and the ability of load balancing is analyzed with a combination of test.