The purpose of this thesis was to analyze the problem of resource load balancing in virtualization clusters. Another aim was to implement a pilot version of resource load balancer for the VMware vSphere Standard-based virtualization cluster. The thesis also inspected available commercial and open source resource load balancers and examined their usability and effectiveness. While designing the custom solution, a modification of the greedy algorithm has been chosen to be used to determine which virtual machines should be migrated and to select their target hosts. Furthermore, experiments have been conducted to determine some parameters for the algorithm. Finally, it was experimentally verified that the implemented solution can be applied to effectively balance virtualization server workloads by live migrating virtual machines running on these hosts.

Doctor of Philosophy / Department of Animal Sciences and Industry / Barry J. Bradford / The mechanisms behind the metabolic changes observed when transition cows are administered monensin, as well as the effects of supplementing mid-lactation cows with two commercial amino acid products were investigated. Traditionally, the effects of monensin are attributed to increased gluconeogenic precursor supply, but recent research indicated that the effects of monensin extend beyond gluconeogenic flux. Thus, the primary objectives of Experiment 1 were to determine if monensin modulates transition cow feeding behavior, ruminal pH, and/or expression of key metabolic genes. Overall, monensin decreased time between meals prepartum (126 vs. 143 ± 5.0 min; P < 0.03) with a trend appearing postpartum (81.4 vs. 88.8 ± 2.9 min; P < 0.08), which could be related to the smaller ruminal pH standard deviation during the first day cows received the lactation ration (0.31 vs. 0.26 ± 0.015; P < 0.02). Monensin also increased liver mRNA abundance of carnitine palmitoyltransferase 1a (0.15 vs. 0.10 ± 0.002 arbitrary units; P < 0.04), which corresponded to a slower rate of liver triglyceride (TG) accumulation from 7 days before calving through 7 days post calving (412 vs. 128 ± 83 mg TG/g protein over this time period; P = 0.03). No significant effects of monensin supplementation were observed on other metabolic parameters or milk production. Overall, these results confirm that the effects of monensin on transition cows extend beyond altered propionate flux. In Experiment 2, mid-lactation cows consuming a control diet containing 26% wet corn gluten feed (dry matter basis) were compared to cows consuming the same diet supplemented with lysine embedded within Ca salts of fatty acids and the isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid, a methionine precursor. This trial was conducted because the NRC (2001) model indicated a lysine deficiency prior to supplementation; however amino acid supplementation had no effects. This trial was then extended to decrease dietary CP from 17.9% to 17.1%, and further increase lysine and methionine supply in the treatment diet. No production or intake effects were observed during this period, but MUN was decreased in the treated group (10.8 vs. 12.5 ± 0.2 mg/dL; P < 0.001).

Procedural human motion generation is still an open area of research. Most research into procedural human motion focus on two problem areas: the realism of the generated motion and the computation time required to generate the motion. Realism is a problem because humans are very adept at spotting the subtle nuances of human motion and so the computer generated motion tends to look mechanical. Computation time is a problem because the complexity of the motion generation algorithms results in lengthy processing times for greater levels of realism. The balancing human problem poses the question of how to procedurally generate, in real-time, realistic standing poses of an articulated human body. This report presents the balancing human algorithm that addresses both concerns: realism and computation time. Realism was addressed by integrating two existing algorithms. One algorithm addressed the physics of the human motion and the second addressed the prediction of the next pose in the animation sequence. Computation time was addressed by identifying techniques to simplify or constrain the algorithms so that the real-time goal can be met. The research methodology involved three tasks: developing and implementing the balancing human algorithm, devising a real-time simulation graphics engine, and then evaluating the algorithm with the engine. An object-oriented approach was used to model the balancing human as an articulated body consisting of systems of rigid-bodies connected together with joints. The attributes and operations of the object-oriented model were derived from existing published algorithms.

Shared resource contention is a significant problem in multi-core systems and can have a negative impact on the system. Memory contention occurs when the different cores in a processor access the same memory resource, resulting in a conflict. It is possible to limit memory contention through resource reservation where a part of the system or an application is reserved a partition of the shared resource. We investigated how applying memory bandwidth restrictions using MemGuard can aid in synchronizing execution times of parallel tasks. We further investigate when memory bandwidth restrictions are applicable. We conduct three experiments to investigate when bandwidth restrictions are applicable. Firstly, we conducted an experiment to pinpoint when the memory bandwidth saturates a core. Secondly, we investigated our adaptive memory partitioning scheme performance against static and no partitioning. Finally, we tested how our adaptive partitioning scheme and static partitioning can isolate a workload against an interfering memory intensive workload running on a separate core. As the experiments only were conducted on one system, pinpointing the general point of contention was difficult, seeing that it can differ significantly from system to system. Through our experiments, we see that memory bandwidth partitioning has the ability to decrease the execution time of feature detection algorithms, which means that memory bandwidth partitioning potentially can help threads to reach their synchronization points simultaneously.

The objective of the thesis is to analyse law, case law, recommendations and opinions and to some extent legal doctrine to produce commercially viable advice (in other words, a check-list) on what to think about when conducting a balancing test as of GDPR Article 6.1 (f)

O ponto de partida desta dissertação são os aspectos metodológicos, quais sejam: (i) contextualização do ordenamento jurídico brasileiro; (ii) emersão da problemática do conflito entre princípios (positivismo versus pós-positivismo ou neoconstitucionalismo); e (iii) relevância da análise do método de sopesamento de princípios proposto por Robert Alexy. Em seguida, o estudo apresenta a discussão sobre teorias do conhecimento travada entre os filósofos Henri Poincaré e Pierre Duhem, demonstrando que a mesma discussão pode ser aplicada ao direito, e, nesse sentido, faz um paralelo com Herbert Hart, Ronald Dworkin e Robert Alexy. Passando pelo determinante Período Iluminista (incluindo os filósofos Jean-Jacques Rousseau e Cesare di Beccaria), a pesquisa evidencia sua influência nos princípios e nos direitos fundamentais consagrados atualmente pelo direito penal brasileiro. Em seguida, a pesquisa expõe os direitos fundamentais, apresenta a teoria do sopesamento ou balanceamento de princípios proposta por Robert Alexy e analisa, na jurisprudência do Supremo Tribunal Federal, como os ministros recorrem a esse método para solução de casos nos quais existe conflito entre os direitos fundamentais. A finalidade é evidenciar que o recurso, pelos juristas brasileiros, não introduziu uma nova maneira de interpretação ou um novo método de tomada de decisões, já que os ministros do STF recorrem à doutrina de Robert Alexy somente para demonstrar erudição; sem de fato aplicar o método proposto por ele, o mencionam para justificar qualquer decisão que já tenha sido tomada com base na subjetividade. Por fim, este estudo apresenta exercícios de aplicação do que a autora entende ser o método do sopesamento aos casos sob análise, e a conclusão foi que há distorções nos resultados em cerca de 30% deles, porcentagem relevante, considerando a importância dos casos analisados pelo STF. A aplicação do método do sopesamento consiste em três sub-regras subsequentes e ordenadas: adequação, necessidade e proporcionalidade em sentido estrito. A proporcionalidade apenas é analisada se a questão não puder ser solucionada pela necessidade e, por sua vez, a necessidade só é analisada se a adequação não for suficiente para solucionar a questão. O estudo demonstra que, quando a análise atinge a sub-regra necessidade, ocorrem os resultados divergentes. / This dissertation starts by the methodological aspects, which are: (i) contextualization of the Brazilian legal system; (ii) emergence of the conflict between principles (positivism versus postpositivism or neoconstitutionalism); and (iii) relevance of the analysis of the balancing of principles proposed by Robert Alexy. Subsequently, we presented the discussion of knowledge theories between the philosophers Henri Poincaré and Pierre Duhem, showing that the same discussion can be applied to law, in this sense we drew a parallel with Herbert Hart, Ronald Dworkin and Robert Alexy. Passing through the determinant Enlightenment Period (including the philosophers Jean-Jacques Rousseau and Cesare di Beccaria), we demonstrate its influence to principles and rights currently consecrated on the Brazilian criminal law. We analyzed on the jurisprudence of the Brazilian Supreme Court (Supremo Tribunal Federal) the application of Robert Alexys theory, known as sopesamento or balancing of principles, to case laws on which are conflict of fundamental rights (including the rights previously presented). The purpose is highlight that the recourse, by Brazilian jurists, did not insert a new interpretation technique or method of decision-making, since the ministers of STF invoke Robert Alexy doctrine solely to show erudition, without in fact apply the method proposed by him and mention him to justify whatsoever decision already taken based on subjectivity. Finally, we made an exercise of apply our understanding of the balancing method to cases under study and the conclusion was for 30% of distortions in the results, percentage relevant considering the importance of the cases analyzed by STF. The application of the balancing method consist on three sub-rules subsequent and ordered: adequacy, need and proportionality in strict sense. The proportionality is only analyzed if the case cannot be solved by need, and, in turn, need is only analyzed if adequacy is insufficient to solved the question. We ascertain that when the analysis achieves the sub-rule of need occurs the divergent results.

Este trabalho apresenta uma análise de comportamento de índices de carga relacionados ao uso e à atividade de memória. São descritos 11 índices que refletem direta ou indiretamente a carga de memória. Esses índices podem ser obtidos facilmente no sistema peracional GNU/Linux através do sistema de arquivos /proc. Uma ferramenta de monitoramento foi criada para facilitar a análise de comportamento, podendo também servir para fornecer informações de carga para políticas de escalonamento. Os valores de cada índice foram monitorados durante a execução de uma carga de trabalho composta por aplicações reais que utilizam altas quantidades de memória. A partir dos resultados é possível descobrir a utilidade de cada índice, indicando como eles podem ser usados para auxiliar políticas de escalonamento a avaliar a carga de memória de uma máquina. Métricas de avaliação de carga originárias da combinação de mais de um índice são descritas. Essas métricas foram criadas em casos em que a combinação de mais de um índice permitia representar a carga de memória com mais precisão do que índices usados isoladamente. As métricas e índices pesquisados proporcionam formas precisas de representar a carga de memória em vários níveis, desde níveis de baixa utilização até níveis de saturação da memória principal com sintomas de ocorrência de thrashing. / This work presents an analysis of the behavior of load indices related to memory usage and activity. It describes 11 indices which reflect memory load, directly or indirectly. These indices may be easily obtained on the GNU/Linux operating system using the /proc filesystem. A monitoring tool has been developed to make the behavior analysis easier, but it can also be employed to provide load information to scheduling policies. The values of each index have been monitored during the execution of a workload composed by real memory-intensive applications. From the monitoring results, it is possible to find out the usefulness of each index, pointing out how it may be used to help scheduling policies evaluate the memory load of a certain computer. Load evaluation metrics have been created combining more than one index, with the objective of characterizing memory load more precisely than just one isolated index. The explored metrics and indices have shown to provide precise forms of representing memory load at several levels, from low utilization levels up to excessive main memory usage with symptoms of thrashing.

Este trabalho analisa o impacto causado no desempenho de uma simulação distribuída quando técnicas de particionamento convencionais são empregadas. Essas técnicas não levam em conta informações inerentes ao estado da simulação. Pelo fato da execução de uma simulação também estar sujeita a sofrer interferências da plataforma, informações sobre a potência computacional de cada recurso utilizado e sobre o tipo de simulação, podem ser aplicadas em seu particionamento. Foram utilizadas informações estáticas, geradas através da avaliação da plataforma com benchmarks, e dinâmicas, obtidas através de índices de carga. Os resultados obtidos da utilização destas técnicas se mostram atrativos, principalmente quando o objetivo é a execução das simulações em ambientes que não disponibilizam políticas de escalonamento específicas e sim políticas convencionais. Nos estudos de casos avaliados, observaram-se ganhos satisfatórios, como a redução de até 24% do tempo de execução, um aumento de até 22% de eficiência e 79% menos rollbacks causados. Percebe-se que dependendo do tempo que se dispõe e dos objetivos pretendidos, as técnicas convencionais podem ser empregadas em simulações distribuídas. Este trabalho também contribui com o aperfeiçoamento das duas ferramentas utilizadas: WARPED e AMIGO. Uma interface de comunicação entre as duas ferramentas foi desenvolvida, ampliando assim seus campos de utilização. / This work analyses the impact caused on distributed simulation performance when conventional partitioning techniques are employed. These techniques do not take into account inherent information about the state of the simulation. Since a simulation execution is subject to platform interference, information about the type of simulations and about the computational power of resources may be applied to the partitioning process. Static performance information, generated from evaluating the platform with benchmarks has been employed, as well as dynamic load information provided by load indices. The results obtained with this approach are attractive, mainly when the objective is to execute simulations on environments which make conventional scheduling policies available, instead of specific policies. The evaluated case studies show satisfactory performance gains of up to 24% of reduction in execution time, 22% of improvement in efficiency and reduction of up to 79% in rollbacks. So, depending on the available time and the aimed objectives, it is worth using conventional techniques to assist distributed simulation partitioning. This work also contributes to the improvement of both tools used in it: Warped and AMIGO. A communication interface has been developed to integrate the tools, extending their capabilities.

Diante dos desafios impostos pelo sistema econômico, características dos mercados e exigências dos clientes, as empresas são forçadas a operar com lotes de produção cada vez menores, dificultando a gestão de operações e a otimização dos sistemas produtivos. Desse modo, intensifica-se nos meios corporativos e acadêmicos a busca por abordagens que possibilitem a criação de diferenciais competitivos de mercado, sendo esta a justificativa prática deste trabalho, que propõe uma sistemática integrada para alocação, sequenciamento e balanceamento de lotes em um horizonte de programação em múltiplas linhas de produção em um sistema multiproduto com operadores polivalentes. A sistemática proposta foi dividida em três fases. A primeira fase utiliza um algoritmo genético multiobjetivo com o intuito de determinar a linha de produção em que cada lote será produzido. A segunda fase é responsável pelo sequenciamento dos lotes produtivos e se apoia em uma alteração da regra Apparent Tardiness Cost (ATC). Na terceira fase utilizou-se o método Ranked Positional Weight (RPW) para balancear a distribuição das tarefas entre os operadores polivalentes de cada linha de produção, respeitando a precedência das tarefas. A sistemática foi aplicada em dados reais do segmento têxtil, aprimorando os indicadores produtivos e de entrega e conferindo maior flexibilidade ao processo frente à demanda sazonal. / Faced with the challenges imposed by the economic system, characteristic of the markets and requirements of the customers, the companies are forced to operate with smaller production batches, making it difficult to manage operations and optimization of the production systems. In this way, the search for improvements that allow the creation of competitive differentials of market is intensified in the corporate and academic circles. This is the practical justification for this work, which proposes an integrated systematics for the allocation, sequencing and balancing of batches in a horizon of programming in multiple production lines in a multiproduct system with multipurpose operators. The systematic proposal was divided into three phases. The first phase uses a multiobjective genetic algorithm with intention to determine the production line in which each batch will be produced. The second phase is responsible for the sequencing of productive batches and is based on a change in the rule Apparent Tardiness Cost (ATC). In the third phase the method Ranked Positional Weight (RPW) was used to balance the distribution of the tasks between the multipurpose operators of each line of production, respecting the precedence of the tasks. The systematics was applied in real data of the textile segment, improving the productive and delivery indicators and giving greater flexibility of the process against the seasonal demand.

Algoritmos de balanceamento de carga são utilizados em sistemas distribuídos para homogeneizar a ocupação dos recursos computacionais disponíveis. A homogeneidade na ocupação do ambiente permite otimizar a alocação de recursos e, conseqüentemente, aumentar o desempenho das aplicações. Com o advento dos sistemas distribuídos de alta escala, fazem-se necessárias pesquisas para a construção de algoritmos de balanceamento de carga que sejam capazes de gerir com eficiência esses sistemas. Essa eficiência é medida através do número de mensagens geradas no ambiente, do suporte a ambientes heterogêneos, do uso de políticas que consomem poucos recursos do sistema, da estabilidade em alta carga, da escalabilidade do sistema e dos baixos tempos de resposta. Com o objetivo de atender as necessidades dos sistemas distribuídos de alta escala, este doutorado propõe, apresenta e avalia um novo algoritmo de balanceamento de carga denominado TLBA (Tree Load Balancing Algorithm). Esse algoritmo organiza os computadores do sistema em uma topologia lógica na forma de árvore, sobre a qual são executadas operações de balanceamento de carga. Para validar o TLBA foi construído um simulador que, submetido a testes, permitiu comprovar suas contribuições, que incluem: o baixo número de mensagens geradas pelas operações de balanceamento de carga; a estabilidade em altas cargas; os baixos tempos médios de resposta de processos. Para validar os resultados de simulação, foi construído um protótipo do TLBA. Esse protótipo confirmou os resultados de simulação e, conseqüentemente, as contribuições do algoritmo. / Load balancing algorithms are applied in distributed systems to homogenize the occupation of the available computational resources. The homogeneity of the environment occupation allows optimising the resource allocation and consequently, increasing the application performance. With the advent of the large-scale distributed systems, it was necessary to start researching the construction of load balancing algorithms which are able to manage these systems with efficiency. This efficiency is measured through the number of messages generated on the environment; the support to heterogeneous environments and the load balance policies which should spend the minimal resources time; the stability in overloaded situations; the system scalability; and the processes average response times, that should be small. With the aim to achieve the large-scale distributed systems requirements, this Ph.D. proposes, presents and evaluates a new load balancing algorithm named TLBA (Tree Load Balancing Algorithm). This algorithm arranges the computers on a logical network topology with a tree format. The load balancing operations are executed over this tree. To evaluate the TLBA algorithm, a simulator was built that was submitted to tests that confirmed the following characteristics: the small number of messages generated by the load balancing operations; the stability in overloaded situations; the small average processes response times. To validate the simulation results a TLBA prototype was implemented. This prototype confirmed the simulation results and consequently the contributions of the proposed algorithm.