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Competitive Analysis of Scheduling Algorithms for Aggregated Links

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Abstract

We study an online job scheduling problem arising in networks with aggregated links. The goal is to schedule n jobs, divided into k disjoint chains, on m identical machines, without preemption, so that the jobs within each chain complete in the order of release times and the maximum flow time is minimized.

We present a deterministic online algorithm \(\mathsf{Block}\) with competitive ratio \(O(\sqrt{n/m})\) , and show a matching lower bound, even for randomized algorithms. The performance bound for \(\mathsf{Block}\) we derive in the paper is, in fact, more subtle than a standard competitive ratio bound, and it shows that in overload conditions (when many jobs are released in a short amount of time), \(\mathsf{Block}\) ’s performance is close to the optimum.

We also show how to compute an offline solution efficiently for k=1, and that minimizing the maximum flow time for k,m≥2 is \({ \mathcal {N}\mathcal {P}}\) -hard. As by-products of our method, we obtain two offline polynomial-time algorithms for minimizing makespan: an optimal algorithm for k=1, and a 2-approximation algorithm for any k.

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References

  1. Bender, M.A., Chakrabarti, S., Muthukrishnan, S.: Flow and stretch metrics for scheduling continuous job streams. In Proc. 9th Symp. on Discrete Algorithms (SODA), pp. 270–279. ACM/SIAM (1998)

  2. Bennett, J.C.R., Partridge, C., Shectman, N.: Packet reordering is not pathological network behavior. IEEE/ACM Trans. Netw. 7(6), 789–798 (1999)

    Article  Google Scholar 

  3. Borodin, A., El-Yaniv, R.: Online Computation and Competitive Analysis. Cambridge University Press, Cambridge (1998)

    MATH  Google Scholar 

  4. Cobb, J.A., Lin, M.: A theory of multi-channel schedulers for quality of service. J. High Speed Netw. 12(1,2), 61–86 (2003)

    Google Scholar 

  5. Feuerstein, E., Mydlarz, M., Stougie, L.: On-line multi-threaded scheduling. J. Sched. 6(2), 167–181 (2003)

    Article  MATH  MathSciNet  Google Scholar 

  6. Gareiss, R.: Is the Internet in trouble? Data Communications Magazine, Sept. 1997

  7. Garey, M.R., Johnson, D.S.: Computers and Intractability: A Guide to the Theory of NP-Completeness. Freeman, San Francisco (1979)

    MATH  Google Scholar 

  8. Graham, R.L.: Bounds for certain multiprocessing anomalies. Bell Syst. Tech. J. 45, 1563–1581 (1966)

    Google Scholar 

  9. IEEE, C.S.: Part 3: carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications. In IEEE Std 802.3. Standard for Information Technology Telecommunications and Information Exchange between Systems Local and Metropolitan Area Networks Specific Requirements. The Institute of Electrical and Electronics Engineers, Inc., 3 Park Avenue, New York, NY 10016-5997, USA, 2002

  10. Jawor, W.: Three dozen papers on online algorithms. SIGACT News 36(1), 71–85 (2005)

    Article  Google Scholar 

  11. Jawor, W., Chrobak, M., Molle, M.: Experimental analysis of scheduling algorithms for aggregated links (2006, in preparation)

  12. Pruhs, K., Torng, E., Sgall, J.: Online scheduling. In: Leung, J.Y.-T. (ed.) Handbook of Scheduling: Algorithms, Models, and Performance Analysis. CRC Press, New York (2004), Chapter 15

    Google Scholar 

  13. Shmoys, D.B., Wein, J., Williamson, D.P.: Scheduling parallel machines on-line. In: McGeoch, L.A., Sleator, D.D. (eds.) On-line Algorithms. DIMACS Series in Discrete Mathematics and Theoretical Computer Science, vol. 7, pp. 163–166. AMS/ACM (1992)

  14. Yao, A.C.C.: Probabilistic computations: towards a unified measure of complexity. In: Proc. 18th Symp. Foundations of Computer Science (FOCS), pp. 222–227. IEEE (1977)

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Correspondence to Marek Chrobak.

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W. Jawor and M. Chrobak supported by NSF grants OISE-0340752 and CCR-0208856.

Work of C. Dürr conducted while being affiliated with the Laboratoire de Recherche en Informatique, Université Paris-Sud, 91405 Orsay. Supported by the CNRS/NSF grant 17171 and ANR Alpage.

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Jawor, W., Chrobak, M. & Dürr, C. Competitive Analysis of Scheduling Algorithms for Aggregated Links. Algorithmica 51, 367–386 (2008). https://doi.org/10.1007/s00453-007-9053-2

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  • DOI: https://doi.org/10.1007/s00453-007-9053-2

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