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arXiv · 2307.13937

On Minimizing Generalized Makespan on Unrelated Machines

Nikhil Ayyadevara·Nikhil Bansal·Milind Prabhu
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Abstract

We consider the Generalized Makespan Problem (GMP) on unrelated machines, where we are given $n$ jobs and $m$ machines and each job $j$ has arbitrary processing time $p_{ij}$ on machine $i$. Additionally, there is a general symmetric monotone norm $\psi_i$ for each machine $i$, that determines the load on machine $i$ as a function of the sizes of jobs assigned to it. The goal is to assign the jobs to minimize the maximum machine load. Recently, Deng, Li, and Rabani (SODA'22) gave a $3$ approximation for GMP when the $\psi_i$ are top-$k$ norms, and they ask the question whether an $O(1)$ approximation exists for general norms $\psi$? We answer this negatively and show that, under natural complexity assumptions, there is some fixed constant $\delta>0$, such that GMP is $\Omega(\log^{\delta} n)$ hard to approximate. We also give an $\Omega(\log^{1/2} n)$ integrality gap for the natural configuration LP.

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Nikhil Ayyadevara, Nikhil Bansal, Milind Prabhu. 2023-07-26. On Minimizing Generalized Makespan on Unrelated Machines. https://arxiv.org/abs/2307.13937

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