On-line scheduling of jobs with fixed start and end times
Theoretical Computer Science - Special issue on dynamic and on-line algorithms
Scheduling on-demand broadcasts: new metrics and algorithms
MobiCom '98 Proceedings of the 4th annual ACM/IEEE international conference on Mobile computing and networking
Scheduling data broadcast to “impatient” users
Proceedings of the 1st ACM international workshop on Data engineering for wireless and mobile access
SODA '94 Proceedings of the fifth annual ACM-SIAM symposium on Discrete algorithms
R × W: a scheduling approach for large-scale on-demand data broadcast
IEEE/ACM Transactions on Networking (TON)
Response time in data broadcast systems: mean, variance and tradeoff
Mobile Networks and Applications
A Comparison of Multicast Pull Models
ESA '02 Proceedings of the 10th Annual European Symposium on Algorithms
A maiden analysis of Longest Wait First
SODA '04 Proceedings of the fifteenth annual ACM-SIAM symposium on Discrete algorithms
Scheduling broadcasts with deadlines
Theoretical Computer Science - Special papers from: COCOON 2003
Online algorithms for the provision of quality of service in networks
Online algorithms for the provision of quality of service in networks
Competitive analysis of most-request-first for scheduling broadcasts with start-up delay
Theoretical Computer Science
Lower bounds on online deadline scheduling with preemption penalties
Information Processing Letters
An Optimal Strategy for Online Non-uniform Length Order Scheduling
AAIM '08 Proceedings of the 4th international conference on Algorithmic Aspects in Information and Management
Improved Randomized Online Scheduling of Unit Length Intervals and Jobs
Approximation and Online Algorithms
A tight analysis of most-requested-first for on-demand data broadcast
COCOON'06 Proceedings of the 12th annual international conference on Computing and Combinatorics
Online interval scheduling: randomized and multiprocessor cases
COCOON'07 Proceedings of the 13th annual international conference on Computing and Combinatorics
Online scheduling with preemption or non-completion penalties
Journal of Scheduling
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In an on-demand data broadcast system, clients make requests for data such as weather forecasts, stock prices and traffic information. The server of the system broadcasts the requested data at some time, and all pending requests on this data are satisfied with this single broadcast. All requests have deadlines. The system can abort the current broadcast for more valuable requests and a preempted broadcast may be restarted from the beginning later. In this paper, we design and analyse online scheduler for scheduling broadcasts in such system. The best previously known upper and lower bounds on the competitive ratio of such schedulers are respectively $\Delta + 2 \sqrt{\Delta} + 2$ and $\sqrt{\Delta}$, where Δ is the ratio between the length of the longest and shortest data pages. In this paper, we design a scheduler that has competitive ratio $\frac{6\Delta}{\log \Delta}+O(\Delta^{5/6})$. We also improve the lower bound of the problem to $\frac{\Delta}{2\ln \Delta}-1$, and hence prove that our scheduler is optimal within a constant factor.