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arXiv · 2502.21197

3.415-Approximation for Coflow Scheduling via Iterated Rounding

Lars Rohwedder·Leander Schnaars
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Abstract

We provide an algorithm giving a $\frac{140}{41}$($<3.415$)-approximation for Coflow Scheduling and a $4.36$-approximation for Coflow Scheduling with release dates. This improves upon the best known $4$- and respectively $5$-approximations and addresses an open question posed by Agarwal, Rajakrishnan, Narayan, Agarwal, Shmoys, and Vahdat [Aga+18], Fukunaga [Fuk22], and others. We additionally show that in an asymptotic setting, the algorithm achieves a ($2+\epsilon$)-approximation, which is essentially optimal under $\mathbb{P}\neq\mathbb{NP}$. The improvements are achieved using a novel edge allocation scheme using iterated LP rounding together with a framework which enables establishing strong bounds for combinations of several edge allocation algorithms.

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Lars Rohwedder, Leander Schnaars. 2025-02-28. 3.415-Approximation for Coflow Scheduling via Iterated Rounding. https://arxiv.org/abs/2502.21197

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