An economic and energy-aware analysis of the viability of outsourcing cluster computing to a cloud

This paper compares the total cost of ownership of a physical cluster with the cost of a virtual Cloud-based cluster. For that purpose, cost models for both the physical cluster and the cluster on the Cloud have been developed. The model for the physical cluster takes into account previous works and incorporates a more detailed study of the costs related to energy consumption and the usage of energy saving strategies. The model for the cluster on the Cloud considers pricing options offered by Amazon EC2, such as reserving instances on a long-term basis, and also considers using tools for powering nodes on and off on demand, in order to avoid the costs associated to keeping idle nodes running. Using these cost models, a comparison is made of physical clusters with Cloud clusters of a similar size and performance. The results show that Cloud clusters are an interesting option for start-ups and other organizations with a high degree of uncertainty with respect to the computational requirements, while physical clusters are still more economically viable for organizations with a high usage rate.