Improved priority based scheduling algorithm for real time embedded systems

摘要

Most of the real time systems are framed with aid of priority based scheduling algorithms. If the task is not scheduled accurately the percentage of deadline missing the tasks will exaggerate. In RTOS, when a high priority task is allowed to preempt the low priority task which results in context switching. Due to context switching, processor time and energy will get famished. To overcome these problems the controlled preemptive EDF (CP-EDF) scheduling algorithm is proposed so that preemptions have been controlled. The objective of the proposed CP-EDF scheduling algorithm is to avoid processor time and energy from getting wasted. The results are compared with fully preemptive EDF (FP-EDF) scheduling algorithm and non preemptive (NP-EDF) scheduling algorithm and concluded that the proposed CP-EDF scheduling algorithm outperforms the existing NP-EDF and FP-EDF scheduling algorithms in terms of success ratio, missing rate and CPU utilization.