Sercon: Server Consolidation Algorithm using Live Migration of Virtual Machines for Green Computing

Virtualization technologies changed the way data centers of enterprises utilize their server resources. Instead of using dedicated servers for each type of application, virtualization allows viewing resources as a pool of unified resources, thereby reducing complexity and easing manageability. Server consolidation technique, which deals with reducing the number of servers used by consolidating applications, is one of the main applications of virtualization in data centers. The latter technique helps to use computing resources more effectively and has many benefits, such as reducing costs of power, cooling and, hence, contributes to the Green IT initiative. In a dynamic data center environment, where applications encapsulated as virtual machines are mapped to and released from the nodes frequently, reducing the number of server nodes used can be achieved by migrating applications without stopping their services, the technology known as live migration. However, live migration is a costly operation; hence, how to perform periodic server consolidation operation in a migration-aware way is a challenging task. We propose server consolidation algorithm - Sercon, which not only minimizes the overall number of used servers, but also minimizes the number of migrations. We verify the feasibility of our algorithm along with showing its scalability by conducting experiments with eight different test cases.