In this work we model multicore platforms as chip multiprocessors made up from two different types cores; each type of cores has different computation capabilities. In this simple asymmetric multicore model we study the problem of executing parallel programs that are represented as DAGs or chains of tasks . We assume 2 (essential) speeds in our proposed platform. We relax this assumption and consider many speedsin our energy considerations. This problem has been considered previously in the field of parallel computing and scheduling theory for the general case where multiprocessor platforms have K distinct speeds. Our model is a bridge between the assumptions in these fields and recent advances in multicore processors technology . We provide a refined analysis of a recent scheduling method. Based on this analysis, we specialize the scheduling policy and provide an algorithm of (3  o(1)) expected approximation factor. Note that this improves the previous best factor (6 for two speeds)  .
In this work we study the problem of scheduling tasks with dependencies in multiprocessor architectures where processors have different speeds. We present the preemptive algorithm "Save-Energy" that given a schedule of tasks it post processes it to improve the energy efficiency without any deterioration of the makespan. In terms of time efficiency, we show that preemptive scheduling in an asymmetric system can achieve the same or better optimal makespan than in a symmetric system. Motivited by real multiprocessor systems, we investigate architectures that exhibit limited asymmetry: there are two essentially different speeds . Interestingly, this special case has not been studied in the field of parallel computing and scheduling theory ; only the general case was studied where processors have K essentially different speeds. We present the non-preemptive algorithm ``Remnants'' that achieves almost optimal makespan . We provide a refined analysis of a recent scheduling method. Based on this analysis, we specialize the scheduling policy and provide an algorithm of (3 + o(1)) expected approximation factor. Note that this improves the previous best factor (6 for two speeds) . We believe that our work will convince researchers to revisit this well studied scheduling problem for these simple, yet realistic, asymmetric multiprocessor architectures .
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model multicore platforms as chip multiprocessors made up from two different types cores; each type of cores has different computation capabilities. In this simple asymmetric multicore model we
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executing parallel programs that are represented as DAGs or chains of tasks
scheduling tasks with dependencies in multiprocessor architectures where processors have different speeds. We present the preemptive algorithm "Save-Energy" that given a schedule of tasks it post processes it to improve the energy efficiency without any deterioration of the makespan. In terms of time efficiency, we show that preemptive scheduling in an asymmetric system can achieve the same or better optimal makespan than in a symmetric system. Motivited by real multiprocessor systems, we investigate architectures that exhibit limited asymmetry: there are two essentially different speeds
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We assume 2 (essential) speeds in our proposed platform. We relax this assumption and consider many speedsin our energy considerations. This problem has been considered previously
Interestingly, this special case has not been studied
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; only
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where multiprocessor platforms have K distinct speeds. Our model is a bridge between the assumptions in these fields and recent advances in multicore processors technology
was studied where processors have K essentially different speeds. We present the non-preemptive algorithm ``Remnants'' that achieves almost optimal makespan
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. We believe that our work will convince researchers to revisit this well studied scheduling problem for these simple, yet realistic, asymmetric multiprocessor architectures