Program instructions, responsive to processor utilization being above a first predetermined upper threshold, automatically change a boot configuration file of the server to increase a number of real processors, physically resident within the server, allocated to LPAR effective upon a next boot-up of the server. Program instructions, responsive to the processor utilization being below a second predetermined lower threshold, automatically change a boot configuration file to decrease a number of the real processors, physically resident within the server, allocated to the LPAR effective upon a next boot-up of the server. Program instructions, responsive to the processor utilization being below a second predetermined lower threshold, automatically change a boot configuration file to decrease a number of the real processors, physically resident within the server, allocated to the LPAR effective upon a next boot-up of the server.