Load Balancing on Virtualized Web Servers

In recent years several Internet applications have been developed. Most of these applications are multi-tier, consisting of application and database tiers (e.g., e-commerce sites and social networks). Most of these applications cannot be supported by a single physical machine and are typically supported by multiple servers. In this paper, we present a virtualized architecture consisting of mechanisms that can be used to allocate resources for both application and database tiers in multiple physical machines. The architecture contains a layer of proxies to permit the load balancing. We also performed an experiment in which we show CPU resources in a cluster of physical machines being allocated/deal located according to client requests. For means of workload generation we have modified the client emulator of the Rubis benchmark tool to simulate workload patterns different of the ramp up/down simulated by Rubis. The main benefit of this architecture is that it requires no implementation cost for load balancing as it uses native mechanisms.