The DPK scheduling algorithm for CMP hard real-time applications

In order to boost the potential power of Chip Multiprocessor (CMP), the DPK (Dynamic priority and 0-1 Knapsack) algorithm is proposed in this paper to handle the scheduling problem of multiple DAG-structure hard real-time applications. Although many DAG scheduling algorithms are created for heterogeneous computing environment, the DPK algorithm is mainly based on the unique characters of CMP, and provides three dispatch queues with different level to schedule the multiple DAG-structure applications as a whole. What's more, the DPK algorithm does not only use the deadline to define the priority of each application. Instead, the algorithm utilizes Laxity, a dynamic parameter to measure the current urgency of each application. Furthermore, at the end of each scheduling step, the algorithm finds other proper unscheduled sub-jobs in any application to fill the idle time slice generated in this scheduling step just like the classical 0-1 Knapsack problems. According to the algorithm analysis and simulation experiments, with the DPK algorithm, the Successful Rate can be increased a lot and the idle time of each processor is reduced.