On-line scheduling algorithms for reducing the largest weighted error incurred by imprecise tasks

The paper proposes online scheduling algorithms that reduce the largest weighted error incurred by preemptive imprecise tasks running on a single processor system. The first one is a two level algorithm. The top level scheduling, which is executed whenever a new task arrives, determines the processing times to be allotted to tasks in such a way to minimize maximum weighted error as well as to minimize total error. The lower level algorithm actually allocates the processor to the tasks. The second algorithm extends the online algorithm studied by W.K. Shih and J.W.S. Liu (1992) by formalizing the top level algorithm mathematically. The numerical simulation shows that the proposed algorithm outperforms the previous works in the sense that it greatly reduces the largest weighted error