Abstract: A system for automatically installing new processor control code in a computing system running old processor control code with minimal disruption in the operation thereof. The new code is loaded into the computing system and compared to the old code to identify values of a plurality of updating variables. Changes in the operation of the computing system are effected based on the values of the updating variables without disrupting the operation thereof. In a specific embodiment, the inventive system includes microcode in which resource management variables are labeled and given predetermined values. The resource management variables are compared to corresponding variables in the old code to determine which resources to control to effect an updating of the system. Thus, substantial changes in microcode are effected automatically and without disruption.