1. A method for modeling a behavior of an LPAR (logical partition) in a simulated computer operating in a time slice dispatch mode, comprising: beginning a next modeling interval; calculating a resource percentage representing a percentage of total resources allocated to the LPAR; calculating a time slice percentage for the LPAR based on the resource percentage; determining a CP (central processor) percentage representing a percentage of time that all physical CPs in the computer being modeled have been allocated to the LPAR; and if the CP percentage is greater than the time slice percentage, causing the simulated computer not to dispatch CPs to the LPAR.