Integrated Scheduling for Operating Systems on Asymmetric Multi-core Processors

Asymmetric multi-core processors(AMP) are more energy efficient than symmetric multi-core processors(SMP) and will be the mainstream of parallel computing architecture in the future.The existing researches on the problem of parallel task scheduling in operating systems(OS) on AMP assumed all cores have constant frequencies.They haven't analyzed the problem theoretically.These researches took neither the energy efficiency nor the universality of the scheduling into account.To solve this problem,a scheduling model based on nonlinear programming is proposed in this paper.Moreover,scheduling principles of comprehensively considering synchronization characteristics of parallel tasks,asymmetry and load of cores are analyzed and adhered.An integrated scheduling algorithm are also proposed based on the model.The algorithm integrated thread scheduling and dynamic voltage and frequency scaling(DVFS) in OS to improve energy efficiency.In addition,the algorithm achieved universality with a flexible parameter adjustment mechanism.It is the first algorithm to exploit thread scheduling and DVFS on AMP simultaneously.The evaluation on real platform demonstrates that the algorithm is universal for different conditions and it always outperforms other scheduling algorithms on asymmetric multi-core processors(by 24%~50%).