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arXiv · 2402.11109

Online Flexible Busy Time Scheduling on Heterogeneous Machines

Adrian Calinescu·Gruia Calinescu·Sami Davies·Samir Khuller·Shirley Zhang
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Abstract

We study the online busy time scheduling model on heterogeneous machines. In our setting, jobs with uniform processing time arrive online with a deadline that becomes known to the algorithm at the job's arrival time. An algorithm has access to machines, each with different associated capacities and costs. The goal is to schedule jobs on machines by their deadline, so that the total cost incurred by the scheduling algorithm is minimized. While busy time scheduling has been well-studied, relatively little is known when machines are heterogeneous (i.e., have different costs and capacities), despite this natural theoretical generalization being the most practical model for clients using cloud computing services. We make significant progress in understanding this model by designing a deterministic online algorithm with competitive ratio 8(2p-1)/p < 16 when all jobs have uniform processing time p. A randomized version of this algorithm is 4(2p-1)/(p \ln 2)-competitive against an oblivious adversary. For unit-processing-time jobs, we give lower bounds of 4 and e (where e is Euler's number) on the competitive ratio of deterministic and randomized online algorithms, respectively. For unit-processing-time jobs with agreeable deadlines, we provide a deterministic 2-competitive online algorithm and a matching lower bound.

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Adrian Calinescu, Gruia Calinescu, Sami Davies, Samir Khuller, Shirley Zhang. 2026-09-18. Online Flexible Busy Time Scheduling on Heterogeneous Machines. https://arxiv.org/abs/2402.11109

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