OpenStack is currently the most popular open source platform for Infrastructure as a Service (IaaS) clouds. OpenStack lets users deploy virtual machines and other instances, which handle different tasks for managing a cloud environment on the fly. A lot of cloud platform offerings, including the Ericsson Cloud System, are based on OpenStack. Despite the popularity of OpenStack, there is currently a limited understanding of how much resource is consumed/needed by components of OpenStack under different operating conditions such as number of compute nodes, number of running VMs, the number of users and the rate of requests to the various services. The master thesis attempts to model the resource demand of the various components of OpenStack in function of different operating condition, identify correlations and evaluate how accurate the predictions are. For this purpose, a physical OpenStack is setup with one strong controller node and eight compute nodes. All the experiments and measurements were on virtual OpenStack components on top of the main physical one. In conclusion, a simple model is generated for idle behavior of OpenStack, starting and stopping a Virtual Machine (VM) API calls which predicts the total CPU utilization based on the number of Compute Nodes and VMs.