1. A method, in a data processing system, for composite contention-aware task scheduling, wherein the data processing system comprises a number of processors, the method comprising: dividing an application into application threads; dividing the application into serial regions and parallel regions; decomposing each application thread into compute tasks and memory tasks, wherein a compute task comprises a group of instructions that perform computational functions and wherein a memory task is a group of instructions that perform memory access operations; for each parallel region, determining a corresponding number of application threads and a corresponding number of concurrent memory tasks, wherein the number of application threads and the number of concurrent memory tasks are less than or equal to the number of hardware threads of the processors; for each parallel region, scheduling the application threads, and the compute tasks and the memory tasks within each application thread, on the number of hardware threads of the processors based on the corresponding number of application threads and the corresponding number of concurrent memory tasks; and applying power management to the plurality of processors based on the corresponding number of application threads and the corresponding number of concurrent memory tasks.