Virtualization of operating systems and network infrastructure plays an important role in current IT projects. With the number of services running on different hardware resources it is easy to provide availability, security and efficiency using virtualizers. All virtualization vendors claim that their hypervisor (virtual machine monitor - VMM) is better than their competitors. In this paper we evaluate performance of different solutions: proprietary software products (Hyper-V, ESXi, OVM, VirtualBox), and open source (Xen). We are using standard benchmark tools to compare efficiency of main hardware components, i.e. CPU (nbench), NIC (netperf), storage (Filebench), memory (ramspeed). Results of each tests are presented
