System and method for using performance monitor to optimize system performance

A method that optimizes system performance using performance monitors is presented. The method gathers thread performance data using performance monitors for threads running on either a first ISA processor or a second ISA processor. Multiple first processors and multiple second processors may be included in a single computer system. The first processors and second processors can each access data stored in a common shared memory. The gathered thread performance data is analyzed to determine whether the corresponding thread needs additional CPU time in order to optimize system performance. If additional CPU time is needed, the amount of CPU time that the thread receives is altered (increased) so that the thread receives the additional time when it is scheduled by the scheduler. In one embodiment, the increased CPU time is accomplished by altering a priority value that corresponds to the thread.