Automated clustering of VMs for scalable cloud monitoring and management

The size of modern datacenters supporting cloud computing represents a major challenge in terms of monitoring and management of system resources. Available solutions typically consider every Virtual Machine (VM) as a black box each with independent characteristics and face scalability issues by reducing the number of monitoring re- source samples, considering in most cases only average CPU utilization of VMs sampled at a very coarse time granularity. We claim that better management without compromising scalability could be achieved by clustering together VMs that show similar behavior in terms of resource utilization. In this paper we propose an automated methodology to cluster VMs depending on the utilization of their resources, assuming no knowledge of the services executed on them. The methodology considers several VM resources, both system- and network-related, and exploits the correlation between the resource demand to cluster together similar VMs. We apply the proposed methodology to a case study with data coming from an enterprise datacenter to evaluate the accuracy of VMs clustering and to estimate the reduction in the amount of data collected. The automatic clustering achieved through our approach may simplify the monitoring requirements and help administrators to take decisions on the management of the resources in a cloud computing datacenter.