## The k-Client Problem (2001)

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Venue: | Journal of Algorithms |

Citations: | 23 - 1 self |

### BibTeX

@MISC{Alborzi01thek-client,

author = {Houman Alborzi and Eric Torng and Patchrawat Uthaisombut and Stephen Wagner},

title = {The k-Client Problem },

year = {2001}

}

### Years of Citing Articles

### OpenURL

### Abstract

Virtually all previous research in online algorithms has focused on single-threaded systems where only a single sequence of requests compete for system resources. To model multithreaded online systems,we define and analyze the k-client problem,a dual of the well-studied k-server problem. In the basic k-client problem,there is a single server and k clients,each of which generates a sequence of requests for service in a metric space. The crux of the problem is deciding which client’s request the single server should service rather than which server should be used to service the current request. We also consider variations where requests have nonzero processing times and where there are multiple servers as well as multiple clients. We evaluate the performance of algorithms using several cost functions including maximum completion time and average completion time. Two of the main results we derive are tight bounds on the performance of several commonly studied disk lg k scheduling algorithms and lower bounds of + 1 on the competitive ratio of any 2 online algorithm for the maximum completion time and average completion time cost functions when k is a power of 2. Most of our results are essentially identical for the maximum completion time and average completion time cost functions.

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Citation Context ...tem resource(s), if any, should be allocated to service the current request. Two of the many examples of interesting problems which fall into this single request sequence model are the paging problem =-=[26, 21, 13]-=- and its generalizations, the k-server and generic task system problems [21, 19, 5]. While the single request sequence model captures many important problems, there are many others which do not fall i... |

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Citation Context ...the many examples of interesting problems which fall into this single request sequence model are the paging problem [26, 21, 13] and its generalizations, the k-server and generic task system problems =-=[21, 19, 5]-=-. While the single request sequence model captures many important problems, there are many others which do not fall into this category, such as some operating system scheduling problems [16, 10, 11, 2... |

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Citation Context ...tem resource(s), if any, should be allocated to service the current request. Two of the many examples of interesting problems which fall into this single request sequence model are the paging problem =-=[26, 21, 13]-=- and its generalizations, the k-server and generic task system problems [21, 19, 5]. While the single request sequence model captures many important problems, there are many others which do not fall i... |

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Citation Context ...tem resource(s), if any, should be allocated to service the current request. Two of the many examples of interesting problems which fall into this single request sequence model are the paging problem =-=[26, 21, 13]-=- and its generalizations, the k-server and generic task system problems [21, 19, 5]. While the single request sequence model captures many important problems, there are many others which do not fall i... |

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Citation Context ...ms [21, 19, 5]. While the single request sequence model captures many important problems, there are many others which do not fall into this category, such as some operating system scheduling problems =-=[16, 10, 11, 22]-=- and some real-time scheduling problems [18, 4, 9]. In a typical problem, there is a single system resource such as a processor and, at any given time, there are multiple requests in the system waitin... |

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Citation Context ... it happens to pass other requests en route to the target request. 1.3 Related Research. We know of only two previous papers which have studied on-line problems with similar input formats. Feuerstein =-=[12]-=- independently developed the multiple client input model and used it to define the multi-threaded paging problem. This problem is a generalization of the traditional paging problem where each client r... |

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