Made available in DSpace on 2016-04-25T19:20:40Z (GMT). No. of bitstreams: 1 Dissertacao Cristiane Moreira Cobra.pdf: 473312 bytes, checksum: d1b9dde9c5ab70a101b4c2b0e7c58e15 (MD5) Previous issue date: 2006-05-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work is the result of a bibliographic and theorical research about Patativa do Assaré´s poetry. It ascertains that the poetical discourse present in his work indicates the elaboration of contention and resistance concerning the inequality lived by his group, which uses the popular Christian religiosity as reference. The memory, orality, re-signification of concepts instituted by Church´s ortodoxy as well as the approach of pertinent themes to the members of this group are emphasized as elements of his resistent poetry. The analytical interpretation of the poems is based on the literary theory of Alfredo Bosi, the idea of identity metamorphosis developed by Ciampa as well as the analysis of Culture developed by Renato Ortiz and Clifford Geerts. Patativa makes use of the Christian Catholic religious imaginary as source of sense and meaning. He reveals to the popular culture typical forms of understanding the religiosity and the idea of Divine Providence. Furthermore he recreates, re-elaborates, re-invents and re-signifies these popular ways of attributing sense and meaning to the reality. When translated into utopia the contesting aspect present in Patativa´s poetry denotes a form of resistance. His poems manifest prayer, prophecy, value and critical conciousness of past and present, as well as hope based on popular Christian faith. The poetical discourse reveals itself as prophetic. This work contributes to the discussion about religiosity and Brazilian popular culture regarding the elaboration of a popular poetical hermeneutics. Besides, it propitiates a conception of the popular literature under models until then proclaimed as erudite. Its main conclusion is that the popular poetry of Patativa corroborates the constitution of a northeastern identity when it brings back the memory, the values, as well as the group´s self steem. Considering the identity process as a metamorphosis, which includes environmental and inner circumstances, the discourse produced by the poet is manifested as creative hermeneutics which brings sense to the world / Este trabalho é fruto de uma pesquisa bibliográfica e teórica sobre a poesia de Patativa do Assaré; constata que o discurso poético constituído em sua obra aponta para elaboração de uma forma de contestação e resistência diante das desigualdades vivenciadas pelo seu grupo, que toma por referência a religiosidade cristã popular. Como elementos dessa poética resistente ressaltamos a memória, a oralidade, a ressignificação de conceitos instituídos pela ortodoxia da Igreja, bem como a abordagem de temas pertinentes aos membros desse grupo. A interpretação analítica dos poemas tem como referências a teoria literária de Alfredo Bosi, a idéia de metamorfose identitária desenvolvida por Ciampa, bem como as análises da Cultura desenvolvidas por Renato Ortiz e Clifford Geertz. Patativa recorre ao imaginário religioso cristão católico como fonte de sentido e significado, revelando formas típicas à Cultura Popular de compreensão da religiosidade e da idéia de Divina Providência; não somente revela, mas recria, reelabora, reinventa e ressignifica essas maneiras populares de atribuir sentido e significado à realidade. O aspecto contestatório presente na poesia de Patativa significa uma forma de resistência ao traduzir-se em utopia; seus poemas revelam-se prece e profecia, valorização e consciência crítica do passado e do presente, bem como esperança no futuro com bases na fé cristã popular. O discurso poético se mostra assim discurso profético. O trabalho contribui com a discussão sobre a religiosidade e a cultura popular no Brasil ao considerar a elaboração de uma hermenêutica poética popular, além disso, propicia uma consideração da literatura popular sob moldes até então proclamados como eruditos. Sua conclusão principal é que a poética popular de Patativa corrobora a constituição de uma identidade nordestina ao resgatar a valorização da memória, dos valores, bem como da auto-estima desse grupo; considerando o processo identitário como metamorfose que inclui condições do meio e condições internalizadas, o discurso elaborado pelo poeta revela-se como hermenêutica criativa, como forma de significar e doar sentido ao mundo

The objective of the research is to design an electro-optic control for the Active Vertical Coupler-based Optical Cross-point Switch (OXS). The electronic control should be implemented on Printed Circuit Board (PCB) and therefore the design will include the PCB design as well. The aim of the electronic control board is to process the headers of the packets prior to entering the OXS to be switched and from the information in the headers, determine the state that the OXS should be configured in. It should then configure the optical cross-point accordingly. The electronic control board should show flexibility in the sense that it can handle different types of traffic and resolve possible contention that may occur. The research seeks to understand the problems associated with Photonic Packet Switching (PPS) networks. Two of the main problems identified in a PPS network are contention resolution and the lack of variable delays for storing optical packets. The OXS was analyzed and found to meet the requirements for future ultra-high speed PPS network technology with its high extinction ratio, wide optical bandwidth, ultra-fast switching speed and low crosstalk levels. Photonic packets were generated with 4-bit, 8-bit or 16-bit headers at a bit rate of 155 Mbit/s followed by a PRBS (Pseudo Random Bit Sequence) payload at 10 Gbit/s. Different scenarios were created with these types of packets and the electro-optic control and OXS were subjected to these scenarios with the aim of testing the flexibility of the electro-optic control to control the OXS. These scenarios include: <ul><li>Fixed length packets arriving synchronously at one input of the OXS. Some packets are destined for output 1, some are destined for output 2 and some are destined for output 3, therefore realizing a 1-to-3 optical switch.</li> <li>Eight variable length packets arriving synchronously at the OXS at one input, all of them destined for one output. The electro-optic control should open the switch cell for the correct amount of time.</li> <li>Three variable length packets arriving synchronously and asynchronously at one input of the OXS. Some packets are destined for output 1 while other packets are destined for output 2. The electro-optic control should open the correct switch cell for the correct amount of time.</li> <li>Two fixed length packets arriving at the OXS synchronously on different input ports at the same time, both destined for the same output port. The electro-optic control should detect the contention and switch the packets in such a way as to resolve the contention.</li> The electro-optic control and OXS managed to switch all these types of data traffic (scenarios) successfully and resolve the contention with an optical delay buffer. The success of the results was measured in two ways. Firstly it was deemed successful if the expected output sequence was measured at the corresponding output ports. Secondly it was successful if the degradation in quality of the packet was not drastic, meaning the output packets should have an BER (Bit Error Rate) of less than 10-9. The quality of the packets was measured in the form of eye diagrams before and after the switching and then compared. The research resulted in the design and implementation of a flexible electro-optic control for the OXS. The problem of contention was resolved for fixed length synchronous packets and a proposal is discussed to store packets for variable lengths of time by using the OXS. This electro-optic control has the potential to control the OXS for traffic with higher complexities and make the OXS compatible with future developments. / Dissertation (MEng (Electronic Engineering))--University of Pretoria, 2008. / Electrical, Electronic and Computer Engineering / MEng / unrestricted

The number of processor cores and on-chip cache size has been increasing on chip multiprocessors (CMPs). As a result, leakage power dissipated in the on-chip cache has become very significant. We explore various techniques to switch-off the over-allocated cache so as to reduce leakage power consumed by it. A large cache offers non-uniform access latency to different cores present on a CMP and such a cache is called “Non-Uniform Cache Architecture (NUCA)”. Past studies have explored techniques to reduce leakage power for uniform access latency caches and with a single application executing on a uniprocessor. Our ideas of power optimized caches are applicable to any memory technology and architecture for which the difference of leakage power in the on-state and off-state of on-chip cache bank is significant. Switching off the last level shared cache on a CMP is a challenging problem due to concurrently executing threads/processes and large dispersed NUCA cache. Hence, to determine cache requirement on a CMP, first we propose a new highly accurate method to estimate working set size of an application, which we call “tagged working set size estimation (TWSS)” method. This method has a negligible hardware storage overhead of 0.1% of the cache size. The use of TWSS is demonstrated by adaptively adjusting cache associativity. Our ideas of adaptable associative cache is scalable with respect to the number of cores present on a CMP. It uses information available locally in a tile on a tiled CMP and thus avoids network access unlike other commonly used heuristics such as average memory access latency and cache miss ratio. Our implementation gives 25% and 19% higher EDP savings than that obtained with average memory access latency and cache miss ratio heuristics on a static NUCA platform (SNUCA), respectively. Cache misses increase with reduced cache associativity. Hence, we also propose to map some of the L2 slices onto the rest L2 slices and switch-off mapped L2 slices. The L2 slice includes all L2 banks in a tile. We call this technique the “remap policy”. Some applications execute with lesser number of threads than available cores during their execution. In such applications L2 slices which are farther to those threads are switched-off and mapped on-to L2 slices which are located nearer to those threads. By using nearer L2 slices with the help of remapped technology, some applications show improved execution time apart from reduction in leakage power consumption in NUCA caches. To estimate the maximum possible gains that can be obtained using the remap policy, we statically determine the near-optimal remap configuration using the genetic algorithms. We formulate this problem as a energy-delay product minimization problem. Our dynamic remap policy implementation gives energy-delay savings within an average of 5% than that obtained with the near-optimal remap configuration. Energy-delay product can also be minimized by improving execution time, which depends mainly on the static and dynamic NUCA access policies (DNUCA). The suitability of cache access policy depends on data sharing properties of a multi-threaded application. Hence, we propose three indices to quantify data sharing properties of an application and use them to predict a more suitable cache access policy among SNUCA and DNUCA for an application.

The number of processor cores and on-chip cache size has been increasing on chip multiprocessors (CMPs). As a result, leakage power dissipated in the on-chip cache has become very significant. We explore various techniques to switch-off the over-allocated cache so as to reduce leakage power consumed by it. A large cache offers non-uniform access latency to different cores present on a CMP and such a cache is called “Non-Uniform Cache Architecture (NUCA)”. Past studies have explored techniques to reduce leakage power for uniform access latency caches and with a single application executing on a uniprocessor. Our ideas of power optimized caches are applicable to any memory technology and architecture for which the difference of leakage power in the on-state and off-state of on-chip cache bank is significant. Switching off the last level shared cache on a CMP is a challenging problem due to concurrently executing threads/processes and large dispersed NUCA cache. Hence, to determine cache requirement on a CMP, first we propose a new highly accurate method to estimate working set size of an application, which we call “tagged working set size estimation (TWSS)” method. This method has a negligible hardware storage overhead of 0.1% of the cache size. The use of TWSS is demonstrated by adaptively adjusting cache associativity. Our ideas of adaptable associative cache is scalable with respect to the number of cores present on a CMP. It uses information available locally in a tile on a tiled CMP and thus avoids network access unlike other commonly used heuristics such as average memory access latency and cache miss ratio. Our implementation gives 25% and 19% higher EDP savings than that obtained with average memory access latency and cache miss ratio heuristics on a static NUCA platform (SNUCA), respectively. Cache misses increase with reduced cache associativity. Hence, we also propose to map some of the L2 slices onto the rest L2 slices and switch-off mapped L2 slices. The L2 slice includes all L2 banks in a tile. We call this technique the “remap policy”. Some applications execute with lesser number of threads than available cores during their execution. In such applications L2 slices which are farther to those threads are switched-off and mapped on-to L2 slices which are located nearer to those threads. By using nearer L2 slices with the help of remapped technology, some applications show improved execution time apart from reduction in leakage power consumption in NUCA caches. To estimate the maximum possible gains that can be obtained using the remap policy, we statically determine the near-optimal remap configuration using the genetic algorithms. We formulate this problem as a energy-delay product minimization problem. Our dynamic remap policy implementation gives energy-delay savings within an average of 5% than that obtained with the near-optimal remap configuration. Energy-delay product can also be minimized by improving execution time, which depends mainly on the static and dynamic NUCA access policies (DNUCA). The suitability of cache access policy depends on data sharing properties of a multi-threaded application. Hence, we propose three indices to quantify data sharing properties of an application and use them to predict a more suitable cache access policy among SNUCA and DNUCA for an application.

Denna rapport behandlar prestandaproblem i den nyligen standardiserade Mesh kommunikationsstandarden (IEEE 802.11s). I denna rapport, undersöker och förbättra vi ett förhållande som resulterar i reduktion av genomströmningen i en kedja av noder topologi. IEEE802.11s är mycket lovande med många fördelar för både IoT-systemen och trådlösa nätverk i båda hemmet och arbete.Vi arbetar med frågan om orättvisa när CSMA/CA tillämpas, vilket orsakar genomströmningsreduktion på grund av paketförluster och indikerar svältning. Vi analyserar konsekvenserna av Collision Avoidance (CA) mekanism och föreslår en ersättning för CA som är både rättvist och samtidigt kan upprätthålla undvikande av kollisioner. Vi implementera detta i en simulator och resultatet visar på betydligt högre end-to-end-genomströmning än standard CSMA/CA och inga paketförluster på grund av buffertspill. / This thesis rapport deals with the performance issues of the newly standardized Wireless mesh protocol (IEEE 802.11s). In this thesis, we work on improving the conditions that results in throughput degradation in a chain of nodes topology. The mesh standard is very promising with many advantages for both IoT systems and home wireless networks.We work on the issue of unfairness when CSMA/CA is applied, which causes throughput degradation due to packet loss and indicates starvation. We analyze the implication of the Collision Avoidance (CA) mechanism and propose a replacement for the CA that is both fair and able to maintain collision avoidance. We implement this in a simulator and the result shows significantly higher end-to-end throughput compared to the original CSMA/CA and no packet loss due to buffer overflow.

Ce travail se concentre sur comment un acteur justifierait ses actions dans des 'environnements hétérogènes et fragmentés. Le but est de démontrer qu’en l’absence d’un principe d’accord contraignant les actions des acteurs, les relations entre les partenaires d’action égaux basculeraient dans la polyarchie et celles entre les partenaires d’action inégaux basculeraient respectivement dans l’arrangement, la discorde et finalement, la violence. A cette fin, cette recherche se concentre sur les politiques mandataires britanniques en Irak à travers une étude de traitement du mouvement nationalitaire kurde dans la wilaya de Mossoul dans une période s’étendant du 30 octobre 1918 au 5 juin 1926. Le 30 octobre 1918 est la date à laquelle l’Armistice de Moudros a été signée entre les Alliés et l’Empire ottoman (à la fin de la Première Guerre mondiale) suite à laquelle les Britanniques occupèrent Mossoul. Le 5 juin 1926 correspond à la date de la signature du Traité d’Angora qui devait régler la question de la frontière turco-irakienne, connue aussi comme la Question de Mossoul / This study focuses on how an actor justifies its actions in heterogenous and fragmented environments. It aims at proving that in the absence of a principle of agreement constraning the actors’ actions, the relations between equal partners of action turn into polyarchy whilst those between inequal ones end in arrangement, contention and finally, violence. To this end, this research concentrates on the British mandatory policies in Iraq through the management of Kurdish nationalist movement in the wilaya of Mosul from 30rd October 1918 to 5th 1926. The 30rd October 1918 is the date of the signature of Armistice of Mudros between the Allies and the Ottoman Empire at the end of the First World War. It is in the aftermath of this armistice that the British occupied Mosul. In 5th 1926, Turkey and Great Britain signed the Treaty of Angora which settled the question of frontier between Turkey and Irak, a question which is also known as Question of Mosul

L’émergence de la psychiatrie comme discipline distincte de la médecine somatique, dans la première moitié du XIXe siècle, s’inscrit dans le cadre de la réforme de la législation sur les aliénés, qui conduit à la création de nouveaux asiles publics dédiés au traitement des malades mentaux en Angleterre, dont celui du Comté du Middlesex, à Hanwell, en 1831. L’Asile de Hanwell, situé près de Londres, est un asile pour aliénés indigents, qui fonctionne de manière complémentaire par rapport à des institutions telles que les workhouses – emblématiques de la nouvelle Loi sur les Pauvres de 1834 – dans la prise en charge d’individus qui sont dans l’incapacité de subvenir à leurs besoins. Sous la direction du docteur John Conolly (1794-1866), qui, dès sa nomination à la direction médicale de l’établissement en 1839, met en place une politique de non-restraint (abandon des moyens de contention mécaniques) à une échelle jusqu’alors inédite, l’Asile de Hanwell est explicitement conçu comme un outil dont la fonction première est thérapeutique, dénué de toute intention punitive. L’influence que cet établissement exercera sur les institutions similaires en Angleterre dès les années 1840 contribue à l’optimisme thérapeutique quant au traitement des aliénés qui prévaut alors, et l’asile victorien, en dépit de ses imperfections, se veut un authentique refuge et un lieu de soins. La conception thérapeutique du Dr Conolly s’inscrit dans la continuité du traitement moral défini par le médecin français Philippe Pinel, mais s’inspire également des expériences menées à La Retraite (York), ou à l’asile de Lincoln. Cette thérapie innovante a la particularité de mettre l’accent sur la qualité de l’environnement et du mode de vie des patients, ainsi que sur les distractions diverses qui leur sont proposées : jeux, fêtes de Noël, kermesses, lecture, musique, sport et danse. La logique de soins qui s’applique alors, le moral management, repose sur une thérapie d’occupation. L’originalité de ce traitement sur le plan médical s’accompagne d’une dimension sociale, voire politique. En effet, loin de limiter ses ambitions au strict domaine médical, le Dr Conolly, connu pour son engagement en faveur de l’éducation populaire au sein de la Society for the Diffusion of Useful Knowledge, tout autant que pour son soutien au mouvement chartiste, mène un combat permanent, de 1839 à 1852, pour que les patients, hommes et femmes, aient accès à une instruction au sein de l’école de l’Asile, dont la création et le maintien sont loin de faire l’unanimité. Conolly envisage l’éducation comme un élément central, qui va bien au-delà d’une simple distraction pour les malades et représente un véritable outil d’insertion sociale et d’émancipation des classes populaires. Il rejoint en cela une conception owéniste de l’éducation, et l’école de l’Asile de Hanwell copie quasiment trait pour trait l’école de New Lanark telle qu’elle se présentait au début du XIXe siècle. Robert Owen (1771-1858) rend d’ailleurs visite à John Conolly dès sa nomination, au printemps 1839. Étudier l’expérience menée dans cet établissement emblématique sous l’autorité de John Conolly – non sans lien avec les expériences sociales menées par les owénistes – et l’influence que cette expérience a pu avoir par la suite dans le paysage psychiatrique victorien, permet d’analyser le non-restraint dans sa dimension thérapeutique, sociale et politique. L’Asile de Hanwell sera pendant près de trente ans une référence dans le traitement des aliénés, et servira de modèle à bon nombre d’institutions, particulièrement en Angleterre. L’influence de Hanwell s’estompera dans les années 1870, qui verront l’émergence de théories de l’hérédité peu compatibles avec le traitement moral. / The emergence of psychiatry as a separate discipline from general medicine, in the first half of the nineteenth century, was linked to the Lunacy Reform movement (County Asylums Acts) that led to the creation of new public asylums dedicated to the treatment of the mentally ill in England. The Middlesex County Asylum in Hanwell, built in 1831, was one of them. Hanwell Asylum, situated in the western suburbs of London, was a pauper lunatic asylum that operated as a complementary institution to the numerous workhouses – symbols of the New Poor Law of 1834 – taking care of people who were deemed unable to take care of themselves. As soon as he was appointed medical superintendent of the institution, in 1839, Dr John Conolly (1794-1866) implemented a whole new policy of non-restraint, applied on an unprecedented scale, and Hanwell Asylum under his leadership was explicitly and primarily intended to be a therapeutic tool, devoid of any punitive purpose. The influence of Hanwell on similar institutions, from the1840s onwards, contributed to the prevailing therapeutic optimism of the time, and Victorian asylums, despite their defects, were meant to be genuine places of refuge and care. Dr Conolly’s therapeutic methods were coherent with “moral treatment” as defined by French doctor Philippe Pinel, but were also based on previous experiences conducted at the York Retreat or Lincoln Asylum. One of the main features of this pioneering treatment was the special emphasis it placed on the high quality of the patients’ environment and way of life, as well as on the wide range of entertainment offered to them: games, Christmas parties, summer fêtes, reading sessions, music, sport and dancing. The approach favoured in terms of health care, a “moral management” approach, was grounded on the principles of occupational therapy. The originality of this treatment from a medical point of view was reinforced by its social and, indeed, political dimension. From 1839 to 1852, far from limiting his ambitions to a strictly medical field, Dr Conolly – well-known for his commitment to the cause of popular education, as a member of the Society for the Diffusion of Useful Knowledge, as well as for his support of the Chartist movement – actually kept on fighting for the right of male and female patients alike to receive proper instruction within the asylum school, which remained highly controversial and constantly threatened with closure. Conolly viewed education as a central element, going far beyond a mere distraction for the insane and truly constituting a tool for social insertion and a means of emancipation for the lower classes. His views on education were similar to the Owenite conception of education and the asylum school at Hanwell was a faithful replica of the New Lanark School at the beginning of the nineteenth century. Besides, Robert Owen (1771-1858) came to Hanwell Asylum and visited John Conolly soon after he was appointed superintendent there, during the spring of 1839. Studying the case of this emblematic institution and the experience carried out within its premises under John Conolly’s authority – an experience which may not be unrelated to Owenite social experimentation – and analysing the impact this experience may have had within the Victorian psychiatric landscape in the years that followed, is an invaluable way of understanding the non-restraint movement through its various dimensions: therapeutic, social and political. For nearly thirty years, Hanwell Asylum remained a benchmark in the treatment of the insane, and served as a model for many other institutions, particularly in England. Its influence began receding in the 1870s, with the emergence of theories of heredity that were hardly compatible with the tenets of moral management.

Opportunistic selection algorithms have grown in importance as next generation wireless systems strive towards higher data rates and spectral efficiencies. For example, in orthogonal frequency division multiple access(OFDMA), the system bandwidth is divided into many sub channels. For each sub channel, the user with the highest channel gain is opportunistically assigned to it. .Likewise, in a multi-source, multi-destination (MSD) cooperative relay system, a relay node must be assigned for every source-destination (SD) pair. The assignment decisions are based on local channel knowledge and must be fast so as to maximize the time available for data transmission. We develop novel multiple access based splitting-based selection algorithms for OFDMA and MSD systems. These systems are unique in that the same user and relay can be the most suitable one for multiple sub channels and multiple SD pairs, respectively. For OFDMA systems, we propose an algorithm called Split Select that assigns for every sub channel the user with the highest channel gain over it. For MSD systems, we propose a contention-based en masse assignment (CBEA) algorithm that assigns to each SD pair a relay that is capable of aiding it. Both Split Select and CBEA are fast and scale well with the number of nodes. For example, Split Select requires just 2.2 slots, on average, to assign a sub channel to its best user even when there are an asymptotically large number of contending users. Likewise, CBEA often takes far less than one slot, on average, to assign a relay to each SD pair.

Au carrefour de la sociologie de la culture et de la sociologie de la déviance, ce travail porte sur les dimensions festives et oppositionnelles du monde des free parties, qui s’articule autour de manifestations techno clandestines et marginales. A partir d’une enquête ethnographique, il s’agit d’examiner une pratique culturelle et musicale mais aussi de saisir la variété des expressions oppositionnelles que les jeunes engagés dans ce monde y déploient. A la suite d’un travail de clarification théorique, cette recherche s’inspire de la notion de contre-culture, dans laquelle l’idée de conflictualité est centrale. Cet outil conceptuel permet d’explorer diverses facettes de l’univers free, controversé et encore largement méconnu, et notamment sa composante « contre ». On peut ainsi montrer que, si le monde free est loin d’être réductible à ses dimensions oppositionnelles, celles-ci peuvent donner un relief particulier à la fête – et réciproquement. La pertinence du croisement entre l’objet « free parties » et l’outil conceptuel « contre-cultures » est due en partie à la double déviance, sociale et légale, qui caractérise les fêtes techno étudiées. Les différents aspects oppositionnels mis en évidence dans ce monde juvénile, ainsi que la distinction entre non-conformité et contestation qui en émane, permettent d’analyser le rapport entre déviance, illégalité, conflictualité/illégalité à la lumière du cas des free parties. / At the crossroads of the sociology of culture and the sociology of deviance, this work focuses on the festive and oppositional dimensions of the free party world, which revolves around clandestine and marginal techno events. Based on an ethnographic research, this study aims to examine a cultural and musical practice but also to grasp the various oppositional expressions unfolding within this youth culture. After providing a theoretical clarification, I draw on the notion of counterculture, in which the idea of conflict is central. This conceptual tool enables me to explore various facets of the free party universe, controversial and still largely misunderstood, and in particular its antagonistic elements. Thus I show that, while the free party world does not amount to its oppositional dimensions, the latter can enhance the festive experience – and vice versa. The double deviance – both social and legal – characteristic of the studied techno parties makes it all the more relevant to bring together this object of study and the concept of counterculture. The various oppositional aspects of this youth culture I highlight, as well as the resulting distinction between nonconformity and contention, enable me to analyze the relationship between deviance, illegality, and conflict/counterculture in the light of the case of free parties.

[ES] Una de las principales preocupaciones de los centros de datos actuales es maximizar la utilización de los servidores. En cada servidor se ejecutan simultáneamente varias aplicaciones para aumentar la eficiencia de los recursos. Sin embargo, las prestaciones dependen en gran medida de la proporción de recursos que recibe cada aplicación. El mayor número de núcleos (y de aplicaciones ejecutándose) con cada nueva generación de procesadores hace que crezca la preocupación por la interferencia en los recursos compartidos. Esta tesis se centra en mitigar la interferencia cuando diferentes aplicaciones se consolidan en un mismo procesador desde dos perspectivas: computación de alto rendimiento (HPC) y computación en la nube. En el contexto de HPC, esta tesis propone políticas de gestión para dos de los recursos más críticos: la caché de último nivel (LLC) y los núcleos del procesador. La LLC desempeña un papel clave en las prestaciones de los procesadores actuales al reducir considerablemente el número de accesos de alta latencia a memoria principal. Se proponen estrategias de particionado de la LLC tanto para cachés inclusivas como no inclusivas, ambos diseños presentes en los procesadores para servidores actuales. Para los esquemas, se detectan nuevos comportamientos problemáticos y se asigna un mayor espacio de caché a las aplicaciones que hacen mejor uso de este. En cuanto a los núcleos del procesador, muchas aplicaciones paralelas (como aplicaciones de grafos) no escalan bien con un mayor número de núcleos. Además, el planificador de Linux aplica una estrategia de tiempo compartido que no ofrece buenas prestaciones cuando se ejecutan aplicaciones de grafo. Para maximizar la utilización del sistema, esta tesis propone ejecutar múltiples aplicaciones de grafo en el mismo procesador, asignando a cada una el número óptimo de núcleos (y adaptando el número de hilos creados) dinámicamente. En cuanto a la computación en la nube, esta tesis aborda tres grandes retos: la compleja infraestructura de estos sistemas, las características de sus aplicaciones y el impacto de la interferencia entre máquinas virtuales (MV). Primero, esta tesis presenta la plataforma experimental desarrollada con los principales componentes de un sistema en la nube. Luego, se presenta un amplio estudio de caracterización sobre un conjunto de aplicaciones de latencia crítica representativas con el fin de identificar los puntos que los proveedores de servicios en la nube deben tener en cuenta para mejorar el rendimiento y la utilización de los recursos. Por último, se realiza una propuesta que permite detectar y estimar dinámicamente la interferencia entre MV. El enfoque usa métricas que pueden monitorizarse fácilmente en la nube pública, ya que las MV deben tratarse como "cajas negras". Toda la investigación descrita se lleva a cabo respetando las restricciones y cumpliendo los requisitos para ser aplicable en entornos de producción de nube pública. En resumen, esta tesis aborda la contención en los principales recursos compartidos del sistema en el contexto de la consolidación de servidores. Los resultados experimentales muestran importantes ganancias sobre Linux. En los procesadores con LLC inclusiva, el tiempo de ejecución (TT) se reduce en más de un 40%, mientras que se mejora el IPC más de un 3%. Con una LLC no inclusiva, la equidad y el TT mejoran en un 44% y un 24%, respectivamente, al mismo tiempo que se mejora el rendimiento hasta un 3,5%. Al distribuir los núcleos del procesador de forma eficiente, se alcanza una equidad casi perfecta (94%), y el TT se reduce hasta un 80%. En entornos de computación en la nube, la degradación del rendimiento puede estimarse con un error de un 5% en la predicción global. Todas las propuestas presentadas han sido diseñadas para ser aplicadas en procesadores comerciales sin requerir ninguna información previa, tomando las decisiones dinámicamente con datos recogidos de los contadores de prestaciones. / [CAT] Una de les principals preocupacions dels centres de dades actuals és maximitzar la utilització dels servidors. A cada servidor s'executen simultàniament diverses aplicacions per augmentar l'eficiència dels recursos. Tot i això, el rendiment depèn en gran mesura de la proporció de recursos que rep cada aplicació. El nombre creixent de nuclis (i aplicacions executant-se) amb cada nova generació de processadors fa que creixca la preocupació per l'efecte causat per les interferències en els recursos compartits. Aquesta tesi se centra a mitigar la interferència en els recursos compartits quan diferents aplicacions es consoliden en un mateix processador des de dues perspectives: computació d'alt rendiment (HPC) i computació al núvol. En el context d'HPC, aquesta tesi proposa polítiques de gestió per a dos dels recursos més crítics: la memòria cau d'últim nivell (LLC) i els nuclis del processador. La LLC exerceix un paper clau a les prestacions del sistema en els processadors actuals reduint considerablement el nombre d'accessos d'alta latència a la memòria principal. Es proposen estratègies de particionament de la LLC tant per a caus inclusives com no inclusives, ambdós dissenys presents en els processadors actuals. Per als dos esquemes, se detecten nous comportaments problemàtics i s'assigna un major espai de memòria cau a les aplicacions que en fan un millor ús. Pel que fa als nuclis del processador, moltes aplicacions paral·leles (com les aplicacions de graf) no escalen bé a mesura que s'incrementa el nombre de nuclis. A més, el planificador de Linux aplica una estratègia de temps compartit que no ofereix bones prestacions quan s'executen aplicacions de graf. Per maximitzar la utilització del sistema, aquesta tesi proposa executar múltiples aplicacions de grafs al mateix processador, assignant a cadascuna el nombre òptim de nuclis (i adaptant el nombre de fils creats) dinàmicament. Pel que fa a la computació al núvol, aquesta tesi aborda tres grans reptes: la complexa infraestructura d'aquests sistemes, les característiques de les seues aplicacions i l'impacte de la interferència entre màquines virtuals (MV). En primer lloc, aquesta tesi presenta la plataforma experimental desenvolupada amb els principals components d'un sistema al núvol. Després, es presenta un ampli estudi de caracterització sobre un conjunt d'aplicacions de latència crítica representatives per identificar els punts que els proveïdors de serveis al núvol han de tenir en compte per millorar el rendiment i la utilització dels recursos. Finalment, es fa una proposta que de manera dinàmica permet detectar i estimar la interferència entre MV. L'enfocament es basa en mètriques que es poden monitoritzar fàcilment al núvol públic, ja que les MV han de tractar-se com a "caixes negres". Tota la investigació descrita es duu a terme respectant les restriccions i complint els requisits per ser aplicable en entorns de producció al núvol públic. En resum, aquesta tesi aborda la contenció en els principals recursos compartits del sistema en el context de la consolidació de servidors. Els resultats experimentals mostren que s'obtenen importants guanys sobre Linux. En els processadors amb una LLC inclusiva, el temps d'execució (TT) es redueix en més d'un 40%, mentres que es millora l'IPC en més d'un 3%. En una LLC no inclusiva, l'equitat i el TT es milloren en un 44% i un 24%, respectivament, al mateix temps que s'obté una millora del rendiment de fins a un 3,5%. Distribuint els nuclis del processador de manera eficient es pot obtindre una equitat quasi perfecta (94%), i el TT pot reduir-se fins a un 80%. En entorns de computació al núvol, la degradació del rendiment pot estimar-se amb un error de predicció global d'un 5%. Totes les propostes presentades en aquesta tesi han sigut dissenyades per a ser aplicades en processadors de servidors comercials sense requerir cap informació prèvia, prenent decisions dinàmicament amb dades recollides dels comptadors de prestacions. / [EN] One of the main concerns of today's data centers is to maximize server utilization. In each server processor, multiple applications are executed concurrently, increasing resource efficiency. However, performance and fairness highly depend on the share of resources that each application receives, leading to performance unpredictability. The rising number of cores (and running applications) with every new generation of processors is leading to a growing concern for interference at the shared resources. This thesis focuses on addressing resource interference when different applications are consolidated on the same server processor from two main perspectives: high-performance computing (HPC) and cloud computing. In the context of HPC, resource management approaches are proposed to reduce inter-application interference at two major critical resources: the last level cache (LLC) and the processor cores. The LLC plays a key role in the system performance of current multi-cores by reducing the number of long-latency main memory accesses. LLC partitioning approaches are proposed for both inclusive and non-inclusive LLCs, as both designs are present in current server processors. In both cases, newly problematic LLC behaviors are identified and efficiently detected, granting a larger cache share to those applications that use best the LLC space. As for processor cores, many parallel applications, like graph applications, do not scale well with an increasing number of cores. Moreover, the default Linux time-sharing scheduler performs poorly when running graph applications, which process vast amounts of data. To maximize system utilization, this thesis proposes to co-locate multiple graph applications on the same server processor by assigning the optimal number of cores to each one, dynamically adapting the number of threads spawned by the running applications. When studying the impact of system-shared resources on cloud computing, this thesis addresses three major challenges: the complex infrastructure of cloud systems, the nature of cloud applications, and the impact of inter-VM interference. Firstly, this thesis presents the experimental platform developed to perform representative cloud studies with the main cloud system components (hardware and software). Secondly, an extensive characterization study is presented on a set of representative latency-critical workloads which must meet strict quality of service (QoS) requirements. The aim of the studies is to outline issues cloud providers should consider to improve performance and resource utilization. Finally, we propose an online approach that detects and accurately estimates inter-VM interference when co-locating multiple latency-critical VMs. The approach relies on metrics that can be easily monitored in the public cloud as VMs are handled as ``black boxes''. The research described above is carried out following the restrictions and requirements to be applicable to public cloud production systems. In summary, this thesis addresses contention in the main system shared resources in the context of server consolidation, both in HPC and cloud computing. Experimental results show that important gains are obtained over the Linux OS scheduler by reducing interference. In inclusive LLCs, turnaround time (TT) is reduced by over 40% while improving IPC by more than 3%. In non-inclusive LLCs, fairness and TT are improved by 44% and 24%, respectively, while improving performance by up to 3.5%. By distributing core resources efficiently, almost perfect fairness can be obtained (94%), and TT can be reduced by up to 80%. In cloud computing, performance degradation due to resource contention can be estimated with an overall prediction error of 5%. All the approaches proposed in this thesis have been designed to be applied in commercial server processors without requiring any prior information, making decisions dynamically with data collected from hardware performance counters. / Pons Escat, L. (2023). Interference Analysis and Resource Management in Server Processors: from HPC to Cloud Computing [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/195840