Patent ID: 8452999

Claim:
Data processing apparatus comprising: a data processor having an operating system to perform tasks of an application program; and a power and performance controller to control parameters and modes of execution of said tasks by said data processor, said power and performance controller including a performance predictor to calculate an estimation of required performance of said data processor for said tasks taking account of inactive periods of said tasks, and to adjust the parameters and modes of execution of said tasks by said data processor in response to said estimation; said performance predictor being arranged to distinguish for each of said tasks between: — available inactive periods of said data processor during which said data processor was available to process a same task, said available inactive periods are included in calculating said estimation of required performance for the same task, and unavailable inactive periods of said data processor during which said data processor was not available to process the same task and other tasks, and unavailable active periods of said data processor during which said data processor was not available to process the same task but was processing other tasks, said unavailable inactive periods and unavailable active periods are not included in calculating said estimation of required performance for the same task.