论文信息 - Maximizing Job Completions Online

Maximizing Job Completions Online

We consider the problem of maximizing the number of jobs completed by their deadline in an online single processor system where the jobs are preemptable and have release times. So in the standard three field scheduling notation, this is the online version of the problem 1 | ri ;pmtn | Σ (1 - Ui). We give a constant competitive randomized algorithm for this problem. It is known that no constant competitive deterministic algorithm exists for this problem. This is the first time that this phenomenon, the randomized competitive ratio is constant in spite of the fact that the deterministic competitive ratio is nonconstant, has been demonstrated to occur in a natural online problem. This result is also a first step toward determining how an online scheduler can use additional processors in a real-time setting to achieve competitiveness.

Bala Kalyanasundaram | Kirk Pruhs

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