A Note on NP-Hardness of Preemptive Mean Flow-Time Scheduling for Parallel Machines

Odile Bellenguez-Morineau; Marek Chrobak; Christoph Dürr; Damien Prot

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arXiv · 1404.5424

A Note on NP-Hardness of Preemptive Mean Flow-Time Scheduling for Parallel Machines

Odile Bellenguez-Morineau·Marek Chrobak·Christoph Dürr·Damien Prot

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Abstract

In the paper "The complexity of mean flow time scheduling problems with release times", by Baptiste, Brucker, Chrobak, Dürr, Kravchenko and Sourd, the authors claimed to prove strong NP-hardness of the scheduling problem $P|pmtn,r_j|\sum C_j$, namely multiprocessor preemptive scheduling where the objective is to minimize the mean flow time. We point out a serious error in their proof and give a new proof of strong NP-hardness for this problem.

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Odile Bellenguez-Morineau, Marek Chrobak, Christoph Dürr, Damien Prot. 2014-04-22. A Note on NP-Hardness of Preemptive Mean Flow-Time Scheduling for Parallel Machines. https://arxiv.org/abs/1404.5424

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