DBFarm: A Scalable Cluster for Multiple Databases

摘要

In many enterprise application integration scenarios, middleware has been instrumental in taking advantage of the flexibility and cost efficiency of clusters of computers. Web servers, application servers, platforms such as CORBA, J2EE or .NET, message brokers, and TP-Monitors, just to mention a few examples, are all forms of middleware that exploit and are built for distributed deployment. The one piece in the puzzle that largely remains a centralized solution is the database. There is, of course, much work done on scaling and parallelizing databases. In fact, several products support deployment on clusters. Clustered databases, however, place the emphasis on single applications and target very large databases. By contrast, the middleware platforms just mentioned use clustered deployment not only for scalability but also for efficiently supporting multiple concurrent applications. In this paper we tackle the problem of clustered deployment of a database engine for supporting multiple applications. In the database case, multiple applications imply multiple and different database instances being used concurrently. In the paper we show how to build such a system and demonstrate its ability to support up to 300 different databases without loss of performance.