[en] Energy efficiency remains a prevalent concern in the development of future HPC systems. Thus the next generations of supercomputers are foreseen to be developed as hybrid systems featuring traditional processors, accelerators (such as GPGPUs) and/or low-power processor architectures (ARM, Intel Atom, etc.) primarily designed for the mobile and embedded de- vices market. Also, a confluence with the Cloud Computing (CC) paradigm is anticipated, driven by economic sustainability factors. However, the performance impact of running Cloud middleware on such crossbred platforms remains to be explored, especially on low power processors. In this context, this paper brings two main contributions: (1) the design and implementation of BACH, a framework able to execute automated performance evaluations of Cloud and HPC cluster environments; (2) the concrete validation of the framework for the evaluation of the modern OpenStack Infrastructure-as-a-Service (IaaS) middleware, deployed on a cutting-edge cluster based on ultra low power energy efficient ARM processors. The efficiency in itself is measured with synthetic HPC benchmarks: HPCC (incorporating the well known HPL), HPCG and real world applications from the bioinformatics domain - GROMACS and ABySS. The experimental evaluation revealed an average 24% performance drop in performance for compute-intensive tasks and 65.6% drop in communication capacity compared to the native environment without the IaaS solution, showing a non-negligible impact on the tested platform. To our knowledge, this is one of the first studies of this type, since deployment attempts of the OpenStack infrastructure on top of ARM platforms are in early stages, and are generally performed only for demonstration purposes.