1. A method for placing a virtual machine on a target virtual machine manager out of multiple virtual machine managers, wherein a system management software is connected to the virtual machine managers and selects the target virtual machine manager for placing the virtual machine, the method comprising: the system management software creating a memory profile for all virtual machines hosted on the multiple virtual machine managers, the system management software evaluating probabilities for samepage mapping of the virtual machine to be placed on the multiple virtual machine managers based on the memory profiles of the virtual machines, the system management software selecting under consideration of the probabilities for samepage mapping a most appropriate virtual machine manager as the target virtual machine manager, and the system management software placing the virtual machine on the target virtual machine manager.