Abstract :
Virtualization technologies insert an additional abstraction layer between the operating system and the hardware resources. Virtualization proves to be a very efficient solution, to the cost of effective management at the virtualized layer. Although, virtualization promises better resource utilization, it reduces the available computing resources. CPU, memory and hard disk behavior is a factor with a high impact on the performance of the system. The paper searches to understand how performance in virtualized environments can be improved by means of some performance evaluation experiments. Conducted tests include tests for the CPU, memory and HDD performance evaluation, for two top virtualization technologies providers: VMware [1] and KVM [2]. Overall, VMware behaves better than KVM, but regarding the memory and the HDD, KVM overtakes VMware. At a closer observation, interesting conclusions can be drawn.