Abstract: Cloud computing is a very promising paradigm of service-oriented computing. One major benefit of cloud computing is its elasticity, i.e., the system's capacity to provide and remove resources automatically at runtime. For that, it is essential to design and implement an efficient and effective technique that takes full advantage of the system's potential flexibility. This paper presents a non-intrusive approach that monitors the performance of relational database management systems in a cloud infrastructure, and automatically makes decisions to maximize the efficiency of the provider's environment while still satisfying agreed upon\service level agreements" (SLAs). Our experiments conducted on Amazon's cloud infrastructure, confirm that our technique is capable of automatically and dynamically adjusting the system's allocated resources observing the SLA.