Amortized efficiency of list update and paging rules
Communications of the ACM
Amortized analyses of self-organizing sequential search heuristics
Communications of the ACM - Lecture notes in computer science Vol. 174
An optimal online algorithm for metrical task systems
STOC '87 Proceedings of the nineteenth annual ACM symposium on Theory of computing
A case for redundant arrays of inexpensive disks (RAID)
SIGMOD '88 Proceedings of the 1988 ACM SIGMOD international conference on Management of data
No. 318 on SWAT 88: 1st Scandinavian workshop on algorithm theory
Competitive algorithms for on-line problems
STOC '88 Proceedings of the twentieth annual ACM symposium on Theory of computing
An optimal on-line algorithm for K-servers on trees
SIAM Journal on Computing
The harmonic online K-server algorithm is competitive
STOC '91 Proceedings of the twenty-third annual ACM symposium on Theory of computing
New results on server problems
SIAM Journal on Discrete Mathematics
Theoretical Computer Science
Competitive algorithms for the weighted server problem
Theoretical Computer Science - Special issue on dynamic and on-line algorithms
STOC '94 Proceedings of the twenty-sixth annual ACM symposium on Theory of computing
Balanced allocations (extended abstract)
STOC '94 Proceedings of the twenty-sixth annual ACM symposium on Theory of computing
Online computation and competitive analysis
Online computation and competitive analysis
VLDB '88 Proceedings of the 14th International Conference on Very Large Data Bases
ICALP '89 Proceedings of the 16th International Colloquium on Automata, Languages and Programming
SFCS '86 Proceedings of the 27th Annual Symposium on Foundations of Computer Science
Competitive k-server algorithms
SFCS '90 Proceedings of the 31st Annual Symposium on Foundations of Computer Science
On the effect of a configuration choice on the performance of a mirrored storage system
Journal of Parallel and Distributed Computing
Computer Science Review
On the on-line weighted k-taxi problem
ESCAPE'07 Proceedings of the First international conference on Combinatorics, Algorithms, Probabilistic and Experimental Methodologies
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We study several interesting variants of the k-server problem. In the cnn problem, one server services requests in the Euclidean plane. The difference from the k-server problem is that the server does not have to move to a request, but it has only to move to a point that lies in the same horizontal or vertical line with the request. This, for example, models the problem faced by a crew of a certain news network trying to shoot scenes on the streets of Manhattan from a distance; the crew has only to be on a matching street or avenue. The CNN problem contains as special cases two important problems: the bridge problem, also known as the cow-path problem, and the weighted 2-server problem in which the 2 servers may have different speeds. We show that any deterministic on-line algorithm has competitive ratio at least 6+√17. We also show that some successful algorithms for the k-server problem fail to be competitive. In particular, we show that no natural lazy memoryless randomized algorithm can be competitive. The CNN problem also motivates another variant of the k-server problem, in which servers can move simultaneously, and we wish to minimize the time spent waiting for service. This is equivalent to the regular k-server problem under the L∞ norm for movement costs. We give a 1/2k(k + 1) upper bound for the competitive ratio on trees.