  New dynamic cloud pricing options are emerging with cloud providers offering
resources as a wide range of CPU frequencies and matching prices that can be
switched at runtime. On the other hand, cloud providers are facing the problem
of growing operational energy costs. This raises a trade-off problem between
energy savings and revenue loss when performing actions such as CPU frequency
scaling. Although existing cloud con- trollers for managing cloud resources
deploy frequency scaling, they only consider fixed virtual machine (VM)
pricing. In this paper we propose a performance-based pricing model adapted for
VMs with different CPU-boundedness properties. We present a cloud controller
that scales CPU frequencies to achieve energy cost savings that exceed service
revenue losses. We evaluate the approach in a simulation based on real VM
workload, electricity price and temperature traces, estimating energy cost
savings up to 32% in certain scenarios.
