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arXiv · 1610.04915

Logarithmic price of buffer downscaling on line metrics

Marcin Bienkowski·Martin Böhm·Łukasz Jeż·Paweł Laskoś-Grabowski·Jan Marcinkowski·Jiří Sgall·Aleksandra Spyra·Pavel Veselý
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Abstract

We consider the reordering buffer problem on a line consisting of n equidistant points. We show that, for any constant delta, an (offline) algorithm that has a buffer (1-delta) k performs worse by a factor of Omega(log n) than an offline algorithm with buffer k. In particular, this demonstrates that the O(log n)-competitive online algorithm MovingPartition by Gamzu and Segev (ACM Trans. on Algorithms, 6(1), 2009) is essentially optimal against any offline algorithm with a slightly larger buffer.

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Marcin Bienkowski, Martin Böhm, Łukasz Jeż, Paweł Laskoś-Grabowski, Jan Marcinkowski, Jiří Sgall, Aleksandra Spyra, Pavel Veselý. 2016-10-16. Logarithmic price of buffer downscaling on line metrics. https://arxiv.org/abs/1610.04915

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