Abstract
We consider a natural online optimization problem set on the real line. The state of the online algorithm at each integer time t is a location xt on the real line. At each integer time t, a convex function ft(x) arrives online. In response, the online algorithm picks a new location xt. The cost paid by the online algorithm for this response is the distance moved, namely |xt - xt-1|, plus the value of the function at the final destination, namely Σt(xt). The objective is then to minimize the aggregate cost over all time, namely Σt (|xt - xt-1| + ft(xt)). The motivating application is rightsizing power-proportional data centers. We give a 2-competitive algorithm for this problem. We also give a 3-competitive memoryless algorithm, and show that this is the best competitive ratio achievable by a deterministic memoryless algorithm. Finally we show that this online problem is strictly harder than the standard ski rental problem.
Original language | English |
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Title of host publication | Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques - 18th International Workshop, APPROX 2015, and 19th International Workshop, RANDOM 2015 |
Editors | Naveen Garg, Klaus Jansen, Anup Rao, Jose D. P. Rolim |
Publisher | Schloss Dagstuhl - Leibniz-Zentrum für Informatik |
Pages | 96-109 |
Number of pages | 14 |
ISBN (Electronic) | 9783939897897 |
DOIs | |
Publication status | Published - 1 Aug 2015 |
Event | 18th International Workshop on Approximation Algorithms for Combinatorial Optimization Problems, APPROX 2015, and 19th International Workshop on Randomization and Computation, RANDOM 2015 - Princeton, United States Duration: 24 Aug 2015 → 26 Aug 2015 |
Publication series
Name | Leibniz International Proceedings in Informatics, LIPIcs |
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Volume | 40 |
ISSN (Print) | 1868-8969 |
Conference
Conference | 18th International Workshop on Approximation Algorithms for Combinatorial Optimization Problems, APPROX 2015, and 19th International Workshop on Randomization and Computation, RANDOM 2015 |
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Country/Territory | United States |
City | Princeton |
Period | 24/08/15 → 26/08/15 |
Bibliographical note
Publisher Copyright:© Nikhil Bansal, Anupam Gupta, Ravishankar Krishnaswamy, Kirk Pruhs, Kevin Schewior, and Cliff Stein.
Funding
Supported by NWO grant 639.022.211 and an ERC consolidator grant 617951. Part of this work was done when the author was at Columbia University and supported by NSF grant CCF-1349602. Supported in part by NSF grants CCF-1115575, CNS-1253218, CCF-1421508, and an IBM Faculty Award. Supported by the Deutsche Forschungsgemeinschaft within the research training group "Methods for Discrete Structures" (GRK 1408). Supported in part by NSF grants CCF-1349602 and CCF-1421161.
Keywords
- Scheduling
- Stochastic