Limit theorems for continuous time Markov chains and applications to large scale queueing systems

This thesis discusses limit theorems for density dependent families of continuoustime Markov chains and their application to the stochastic analysis of large scalecloud computing environments and data centers. On the purely theoretical side, wereview the classic functional strong law of large number...

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Detalhes bibliográficos
Autor: Goldsztajn, Diego
Formato: tesis de maestría
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:Uruguay
Recursos:Universidad de la República
Repositorio:COLIBRI
Idioma:inglés
OAI Identifier:oai:colibri.udelar.edu.uy:20.500.12008/21041
Acesso em linha:https://hdl.handle.net/20.500.12008/21041
Access Level:acceso abierto
Palavra-chave:Markov chain
Strong law of large number
Fluid limit
Central limit theorem
Diffusion approximation
Queueing theory
Heavy traffic
Feedback control
Cloud computing
Data center
Descrição
Resumo:This thesis discusses limit theorems for density dependent families of continuoustime Markov chains and their application to the stochastic analysis of large scalecloud computing environments and data centers. On the purely theoretical side, wereview the classic functional strong law of large numbers and central limit theoremdue to Kurtz, which characterize the asymptotic behavior of density dependentfamilies in terms of their drift. In the case of the central limit theorem we provide extensions in two directions: to consider small order perturbations in the transitionrates of the family and non-differentiable drifts. The classic theorems and the latterextensions are used to study the dynamic right sizing of capacity in large scalecloud environments and data centers, aimed at the adjustment of this capacity toan uncertain workload. Under a central queue scheme and Markovian assumptions,we design a policy that eliminates queueing almost completely, at the expense of aslight over-provisioning; ifρthe traffic intensity, then the over-provisioning scales as O(√ρ) whenρ→∞. In this sense our policy automatically adjusts the system’scapacity according to the well-known square root staffing rule.