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1
Schauer, Marek. „Oblíbenost JavaScriptových API internetového prohlížeče“. Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2021. http://www.nusl.cz/ntk/nusl-445496.
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In this work we present the design and implementation of a platform for automated measurement of the use of JavaScript APIs in a web browser. This platform is based on OpenWPM, which is used to instrument the web browser. In our architecture, the browser is extended with a modified Web API Manager extension, which allows to capture calls to JavaScript methods and log information about these calls. The platform was used to perform measurements on a 10,000 websites. From the analysis of the data obtained by the measurement, we found that the most used APIs over measured websites are APIs specified in HTML and DOM standards, High Resolution Time API and Web Cryptography API. Within the APIs that were implemented in Mozilla Firefox after 2016, we identified the Intersection Observer API, Background Tasks API and Resize Observer API as the most frequently used.
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Muller, Bjørn Christian. „Implementering av openBIM i kalkulasjonsprosessen“. Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18463.
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Implementering av openBIM i kalkulasjonsprosessen vil åpne for helt andre muligheter i tilnærmingen til et nytt prosjekt. Med det menes at informasjonen tilknyttet en åpen BIM vil bidra til å gi et bedre grunnlag for konseptvalg og alternative løsninger gjennom gode visualiseringsegenskaper i modellen og en høyere informasjonsgrad i en tidligere fase sammenlignet med en tradisjonell 2D-basert kalkulasjonsprosess. OpenBIM baserer seg i hovedsak på de tre ulike og åpne standardene IFC, IFD og IDM. Når man setter de tre aspektene av openBIM i sammenheng omtaler man åpen BIM som å ha et omforent lagringsformat med enighet om terminologi der BIM-modellen kan kobles opp mot veletablerte forretningsprosesser. Åpen BIM vil dermed fungere som en universell tilnærming til samarbeid, realisering og drift av bygninger basert på åpne standarder og god informasjonsutveksling.En openBIM-basert kalkulasjonsprosess består i å integrere objektene og deres tilhørende attributter/informasjon fra prosjektets ulike BIM-modeller inn i entreprenørens kostnadsdatabase som inneholder prisinformasjon til hvert enkelt objekt eller delobjekt. En slik prosess kan deles inn i tre delprosesser som beskriver arbeidet fra entreprenørens mottakelse av en BIM til ferdig utarbeidet kalkyle. De tre prosessene er; organisering av modellen, oppbygning av objektenes resepter og selve kalkulasjonen av kalkylen.Mengdeberegning sees ofte på som det første steget innenfor kalkulasjonsprosessen og i tradisjonelle kalkulasjonsprosesser utgjør mengdeberegning mellom 50-80 prosent av kalkulatørenes tidsbruk. OpenBIM vil tilrettelegge for en tilnærmet automatisk mengdeberegningsprosess, noe som vil frigjøre mye tid og ressurser hos kalkulatørene der de heller kan fokusere på nøyere vurdering av prosjektets konsept og tilhørende alternative løsninger. På bakgrunn av dette er mengdeberegningsprosessen en av de prosessene som har størst potensial til forbedring ved implementering av openBIM. Selv om åpen BIM tillater automatiske mengdeberegninger vil behovet for kalkulatører i en kalkulasjonsprosess aldri endre seg. Deres arbeidsoppgaver, ved å besitte gode kalkulasjonsegenskaper og samtidig ta hånd om og strukturere informasjonen i en BIM, er helt nødvendig for å utvikle et godt anbud. Dagens kalkulasjonspraksis i MajaTeknobygg framstår i dag som en mindre integrert prosess enn den ville gjort ved full utnyttelse av BIM. Calcus tas i bruk i tidligfasen for å få et hurtig kostnadsestimat av prosjektet. Mengdene hentes ut ved hjelp av et 2D-basert mengdeberegningsprogram for så å implementeres inn i ressurskalkyleverktøyet ByggOffice. Prosessene har lite eller ingen integrasjon mellom seg og nå som både ByggOffice og Calcus har fått innført egen BIM-modul med bedre integrasjon seg imellom vil det å se på samhandlingen mellom programvarene være viktig å gjøre for MajaTeknobygg. Fordelene ved å ta i bruk IFC-formatet i kalkulasjonsprosessen vil helt klart være en bedre samspillprosess og en mer komprimert prosjektering der informasjonsflyten på tvers av ulike fag vil fungere på en god måte. I en slik prosess må kalkulatørene etablere leveringskrav til de ulike aktørene under modelleringsprosessen slik at nødvendig modellinformasjon ligger tilgjengelig til riktig tidspunkt. Det må også avklares og bestemmes et system for objektenes rolle i en BIM. Ofte modelleres det objekt i en BIM uten at det videre er avklart om dets plassering og oppbygning er bestemt eller om det kun brukes til visualisering i modellen. Calcus har lenge vært et godt kalkulasjonsverktøy for vurderinger av kostnadsbildet i tidligfasen av et prosjekt. Med programmets nyetablerte BIM-modul for import/eksport av IFC-modeller vil prosjektet fremstå med blant annet større sporbarhet, (delvis) automatisk mengdeberegning og et bedre produkt for konseptvalg med tilhørende alternative løsninger. Kalkulasjonsverktøyet har i dag en god struktur med kontoplan oppbygd etter NS3451 og integrerte prislinjer basert på NS 3420. Ved standardisert bruk av BIM vil Calcus etter hvert få implementert et standard objektbibliotek som blir viktig i en kalkulasjonsprosess med openBIM.
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Parracho, João Paulo Ligeiro Feteira. „Gateway LinuxMCE: openWrt para aplicações domóticas“. Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/4456.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesA domótica é um campo da automação em franca expansão e, hoje em dia, é recorrente vê-la incorporada em novas construçõoes habitacionais que pretendem níveis de conforto, segurança e tecnologia acima da média. No entanto, um dos problemas desta nova tendência tecnol ógica, tal como a maior parte delas, reside no seu custo muito elevado. Assim, com esta dissertação pretende implementar-se um sistema de baixo custo, devido ao uso de sensores e ao apoio numa distribuição open source dedicada a esta área, o LinuxMCE. Como primeira abordagem, foi estudada a plataforma em questão, métodos da sua instalação e compilação e integração de novos sensores. Depois desta fase inicial, criou-se em C/C++ uma ponte de comunicação entre eles e o sistema (a gateway ), baseada em sockets TCP/IP e, por fim, um demonstrador. Quanto a resultados obtidos, conseguiu-se instalar e configurar a distribuição referida, estabelecer a conexão entre os vários sensores e o LinuxMCE e assegurar o funcionamento do sistema a nível geral (nomeadamente a nível temporal). Existem, no entanto, algumas limitações, visto este sistema já implementar um esquema de troca de mensagens entre ele e os dispositivos externos, que não foi possivel adaptar aos sensores.
Domotics is a field of automation in fast growing expansion, and nowadays it’s usual to notice it incorporated in new habitacional constructions that aim for unprecedented levels of comfort, security and technology. Despite that, one of the issues with this new technological trend, as with most of them, is related with its high cost. Therefore, the goal of this dissertation, is to implement a low cost system of this type, due to the usage of sensors and LinuxMCE, a support open source software dedicated to this area. As a first approach, one has studied the platform, his methods of installation and how to compile and integrate the new sensors. Afterwards, it was created a bridge in C/C++ based on TCP/IP sockets to accommodate the communication between them and the system and a showcase of the overall work. Regarding final results, one has accomplished to properly install and configure the distribution, establish the connection among the various sensors and LinuxMCE and having this last one working (regarding temporal restrains). There are however some limitations, because this system already implemented a scheme of messaging exchange from and to the external devices, that was not possible to adapt to the sensors.
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Stračár, Ivan. „Implementace jednoduché pobočkové ústředny na OpenWRT“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-220608.
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The diploma thesis deals with the system OpenWRT. Installing this system on the router Siemens Gigaset SX762. Describes how to compile and upload the simple package helloworld into this system. The package was tasked invitation simple phrase "Hello World" to the system console of OpenWRT. Package only serve to show that the system OpenWRT allows users to customize it according to their needs. After that it was installed PBX Asterisk into the system OpenWRT. Proper functioning of PBX Asterisk has been verified to make a call between two software phones ZoiPer. Furthermore, the work described telephony application programming interface (TAPI). Some of its fun- ctions, interfaces and packages needed to communicate with the system OpenWRT. In conclusion, the presented test topology and verify the operation of making calls between analog as well as softphones.
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Ešner, Oldřich. „Implementace OpenVPN na platformě Windows CE“. Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235969.
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The motivation for inception of this MSc. thesis which follows on from a term project of the same name was the transfer of the application for building private virtual OpenVPN networks from Windows XP operating system to Windows CE Embedded 6.0 platform. The project deals with virtual private networks in general and looks more closely at its implementation - OpenVPN. It also introduces the basic features of the Windows CE operating system. The project goes on to describe device drivers in NT-based Windows operating systems, the Windows Driver Model used, the NDIS network interface model and also the model of Windows CE drivers - the Stream Interface Model. The project continues with a~description of communication in OpenVPN application and primarily the role of TUN/TAP virtual network interfaces. This is followed by a proposal for transfer of TUN/TAP adapter drivers together with a description of limitations and necessary modifications between both platforms. As a result a TAP network device driver is implemented whose function is verified by test application that emulates the behaviour of a TUN adapter. The project concludes with an evaluation of the achieved results, the possibilities for further work on this theme and with the overall contribution of this project.
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Podobas, Artur. „Thermal-aware Scheduling in OpenMP“. Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-26154.
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Multi-core computer systems have widely been accepted as the future standard in computer architecture. Many simple processing cores bundled together on a single die have been shown more successful in terms of power consumption and execution performance compared to previous large and heavily pipelined uni-core systems. And as the chip dimensions decrease, temperature effects starts to become prominent. Elevated temperature gradients and hotspot on processors put an upper limit on both the execution performance and the life-time of the devices, leading to failures, slowdown and eventually malfunction. Most work involved in software-based temperature management in multi-core systems have been in the kernel-space, hidden from the user. This work hopes to change this, and show that it is possible to make user level schedulers account for temperature changes occurring in the system. OpenMP is the current standard in parallel programming and was used to implement a scheduling policy that uses hardware feedback to effectively try to eliminate elevated temperatures on the chip. The system itself was simulated and modeled using well-established simulators and models. The results were promising, showing a decrease in time spent above the critical temperature with up to 140 times in some benchmarks and a decreased power consumption in all the benchmarks as compared to the Cilk and Breadth-first scheduler. This alone should encourage to more research in this area, and hopefully give rise to a future standard of user level temperature control in parallel based schedulers.
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Aloisi, Giacomo. „OPoly: an OpenMP polyhedral compiler“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23118/.
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In questa tesi introduciamo la polyhedral compilation, una moltitudine di tecniche volte a rappresentare programmi, specialmente quelli che coinvolgono cicli innestati e vettori, rappresentandoli attraverso poliedri parametrici e sfruttando alcune trasformazioni su di essi per analizzare e ottimizzare automaticamente i programmi dati.
In particolare, descriviamo la nostra implementazione di un polyhedral compiler: OPoly.
OPoly è un'applicazione realizzata in Python in grado di parallelizzare automaticamente cicli innestati che possono essere espressi attraverso un insieme di equazioni ricorsive uniformi.
OPoly analizza dei cicli innestati scritti in pseudolinguaggio e genera del codice sorgente parallelizzabile scritto in C e compreso di direttive OpenMP, che può rimpiazzare l'implementazione seriale originale, senza cambiarne il significato.
OPoly sfrutta il linguaggio di modellazione per programmazione a vincoli MiniZinc per modellare il problemi di ottimizzazione dell'approccio poliedrico, che sono cruciali per trovare la trasformazione migliore possibile dal ciclo originale a quello parallelizzabile.
Descriviamo l'architettura di OPoly e diamo alcune soluzioni pratiche a problemi che sorgono implementando un polyhedral compiler.
Infine, compariamo le prestazioni del codice parallelizzabile generato da OPoly con quelle della relativa implementazione originale, studiando il caso di un noto algoritmo scientifico.
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Rejnková, Petra. „Lokalizace a přizpůsobení metodiky OpenUP“. Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-72473.
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These days there are a lot of methodologies which can be used for IS/ICT implementation projects. Apart from traditional rigorous methodologies such as Rational Unified Process (RUP), there are also agile methodologies, which are characterized by positive approach to change and iterative development with very short iterations. One of these methodologies is OpenUP, which combines both agile and rigorous principles. OpenUP covers the most important factors necessary to focus on during software development, but on the other hand it also respects the fact that each project is unique. That is why it offers the possibility to extend or customize its content for specific requirements. The main objective of this diploma is to localize and customize OpenUP methodology for the projects which are running within the courses of software engineering at the University of Economics in Prague. The result if this customization and localization is a methodology suitable for small software projects called MMSP. This diploma also pursues other objectives like to find and characterize tools suitable for administration and customization of the methodology. These objectives were achieved by deep analysis of various sources about OpenUP methodology, information system development projects and methodologies of IS/ICT development. The resulting methodology was not only based on these information but it also results from experiences and best practices from the projects at the University of Economics in Prague and from consultations with experts in practice. The key benefit of this diploma is a complete Czech localized methodology MMSP which can be used both for school and real projects of IS/ICT development. MMSP is available in a form that can be easily embraced, further customized and administrated.
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Sabbagh, Mohammed, und Ahmad Anbarje. „Evaluation of WireGuard and OpenVPN VPN solutions“. Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-98059.
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This project evaluates two types of VPN solutions–WireGuard and OpenVPN.The evaluation is done by four different experiments to measure the maximum throughputof each of the VPN solutions, and a theoretical study on the encryption techniquesthat each VPN solution use. Experiments were conducted using a network performancemeasurement tool called IPerf. By applying static parameters that control themeasurements, such as transferring regular and zip file types, measuring throughputwhen the compression is enabled on the VPN channel and when it is disabled, also,applying measurements with the conditions of the same parameters but with differentoperating systems when using both VPN solutions.one of the measurement results shows that the throughput is about 93 Mbps forWireGuard comparing it with 56 Mbps and 59Mbps for OpenVPN when sendingregular and compressed files respectively.In conclusion, throughput can vary slightly depending on the measurement tooland the version of the software used. Also, the buffer of the measurement tool hasan important role when measuring the throughput, it gives different throughput andpacket loss results which depends on the size of that buffer. Moreover, According to atheoretical study, throughput can also vary depending on the speed of the encryptionalgorithm used. Both VPN solutions use many encryption algorithms, such as AESin OpenVPN, while WireGuard uses ChaCha20 with Poly1305.
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Muddukrishna, Ananya. „Exploiting locality in OpenMP task scheduling“. Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-26318.
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Future multi- and many- core processors are likely to have tens of cores arranged in a tiled architecture where each tile will house a processing core and a bank of the shared last-level cache. The physical distribution of tiles on the processor die gives rise to a Distributed Shared Cache (DSC) architecture where cache access latencies are non-uniform and depend on the physical distance between core and cache bank. In order to maximize cache capacity and favor design simplicity, the address space on a tiled processor is likely to be divided and mapped either statically or dynamically on to the distributed last-level cache such that each cache bank homes certain cache blocks. Given this architecture, an efficient OpenMP 3.0 task scheduler can minimize miss latencies by scheduling tasks on tiles whichare physically closer to the cache banks which home task-relevant data. This master thesis work deals with the design and implementation of a locality-aware user-level runtime OpenMP 3.0 task scheduler for a simulated tiled multicore architecture. Guided by programmer hints, the scheduler extracts locality information pertaining to the data referenced by a task and schedules the task accordingly on the core closest to the L2 slice homing the largest amount of data. Initial results of performance comparison against a work-first randomized work-stealing cilk-like scheduler and a breadth-first randomized work-stealing scheduler have revealed problems with the locality-aware scheduler and have created ground for deeper exploration in the areas of programmer locality characterization and feedback-based extraction of locality information.
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Stadler, Jacques. „Towards dynamic threading support for OpenMP“. Zurich : ETH, Swiss Federal Institute of Technology, Laboratory for Software Technology, 2009. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=432.
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Royuela, Alcázar Sara. „High-level compiler analysis for OpenMP“. Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/620642.
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Nowadays, applications from dissimilar domains, such as high-performance computing and high-integrity systems, require levels of performance that can only be achieved by means of sophisticated heterogeneous architectures. However, the complex nature of such architectures hinders the production of efficient code at acceptable levels of time and cost. Moreover, the need for exploiting parallelism adds complications of its own (e.g., deadlocks, race conditions,...). In this context, compiler analysis is fundamental for optimizing parallel programs. There is however a trade-off between complexity and profit: low complexity analyses (e.g., reaching definitions) provide information that may be insufficient for many relevant transformations, and complex analyses based on mathematical representations (e.g., polyhedral model) give accurate results at a high computational cost.
A range of parallel programming models providing different levels of programmability, performance and portability enable the exploitation of current architectures. However, OpenMP has proved many advantages over its competitors: 1) it delivers levels of performance comparable to highly tunable models such as CUDA and MPI, and better robustness than low level libraries such as Pthreads; 2) the extensions included in the latest specification meet the characteristics of current heterogeneous architectures (i.e., the coupling of a host processor to one or more accelerators, and the capability of expressing fine-grained, both structured and unstructured, and highly-dynamic task parallelism); 3) OpenMP is widely implemented by several chip (e.g., Kalray MPPA, Intel) and compiler (e.g., GNU, Intel) vendors; and 4) although currently the model lacks resiliency and reliability mechanisms, many works, including this thesis, pursue their introduction in the specification.
This thesis addresses the study of compiler analysis techniques for OpenMP with two main purposes: 1) enhance the programmability and reliability of OpenMP, and 2) prove OpenMP as a suitable model to exploit parallelism in safety-critical domains. Particularly, the thesis focuses on the tasking model because it offers the flexibility to tackle the parallelization of algorithms with load imbalance, recursiveness and uncountable loop based kernels. Additionally, current works have proved the time-predictability of this model, shortening the distance towards its introduction in safety-critical domains.
To enable the analysis of applications using the OpenMP tasking model, the first contribution of this thesis is the extension of a set of classic compiler techniques with support for OpenMP.
As a basis for including reliability mechanisms, the second contribution consists of the development of a series of algorithms to statically detect situations involving OpenMP tasks, which may lead to a loss of performance, non-deterministic results or run-time failures.
A well-known problem of parallel processing related to compilers is the static scheduling of a program represented by a directed graph. Although the literature is extensive in static scheduling techniques, the work related to the generation of the task graph at compile-time is very scant. Compilers are limited by the knowledge they can extract, which depends on the application and the programming model. The third contribution of this thesis is the generation of a predicated task dependency graph for OpenMP that can be interpreted by the runtime in such a way that the cost of solving dependences is reduced to the minimum.
With the previous contributions as a basis for determining the functional safety of OpenMP, the final contribution of this thesis is the adaptation of OpenMP to the safety-critical domain considering two directions: 1) indicating how OpenMP can be safely used in such a domain, and 2) integrating OpenMP into Ada, a language widely used in the safety-critical domain.Actualment, aplicacions de dominis diversos com la computació d'altes prestacions i els sistemes d'alta integritat, requereixen nivells de rendiment assolibles només mitjançant arquitectures heterogènies sofisticades. No obstant, la natura complexa d'aquestes dificulta la producció de codi eficient en un temps i cost acceptables. A més, la necessitat d’explotar paral·lelisme introdueix complicacions en sí mateixa (p. ex. bloqueig mutu, condicions de carrera,...). En aquest context, l'anàlisi de compiladors és fonamental per optimitzar programes paral·lels. Existeix però un equilibri entre complexitat i beneficis: la informació obtinguda amb anàlisis simples (p. ex. definicions abastables) pot ser insuficient per moltes transformacions rellevants, i anàlisis complexos basats en models matemàtics (p. ex. model polièdric) faciliten resultats acurats a un alt cost computacional. Existeixen molts models de programació paral·lela que proporcionen diferents nivells de programabilitat, rendiment i portabilitat per l'explotació de les arquitectures actuals. En aquest marc, OpenMP ha demostrat molts avantatges respecte dels seus competidors: 1) el seu nivell de rendiment és comparable a models molt ajustables com CUDA i MPI, i proporciona més robustesa que llibreries de baix nivell com Pthreads; 2) les extensions que inclou la darrera especificació satisfan les característiques de les actuals arquitectures heterogènies (és a dir, l’acoblament d’un processador principal i un o més acceleradors, i la capacitat d'expressar paral·lelisme de tasques de gra fi, ja sigui estructurat o sense estructura; 3) OpenMP és àmpliament implementat per venedors de xips (p. ex. Kalray MPPA, Intel) i compiladors (p. ex. GNU, Intel); i 4) tot i que el model actual manca de mecanismes de resiliència i fiabilitat, molts treballs, incloent aquesta tesi, busquen la seva introducció a l'especificació. Aquesta tesi adreça l'estudi de tècniques d’anàlisi de compiladors amb dos objectius: 1) millorar la programabilitat i la fiabilitat de OpenMP, i 2) provar que OpenMP és un model adequat per explotar paral·lelisme en sistemes crítics. En particular, la tesi es centra en el model de tasques per què aquest ofereix la flexibilitat per abordar aplicacions amb problemes de balanceig de càrrega, recursivitat i bucles incomptables. A més, treballs recents han provat la predictibilitat en qüestió de temps del model, escurçant la distància cap a la seva introducció en sistemes crítics. Per a poder analitzar aplicacions que utilitzen el model de tasques d’OpenMP, la primera contribució d’aquesta tesi consisteix en l’extensió d'un conjunt de tècniques clàssiques de compilació per suportar OpenMP. Com a base per incloure mecanismes de fiabilitat, la segona contribució consisteix en el desenvolupament duna sèrie d'algorismes per detectar de forma estàtica situacions que involucren tasques d’OpenMP, i que poden conduir a una pèrdua de rendiment, resultats no deterministes, o fallades en temps d’execució. Un problema ben conegut del processament paral·lel relacionat amb els compiladors és la planificació estàtica d’un programa representat mitjançant un graf dirigit. Tot i que la literatura sobre planificació estàtica és extensa, aquella relacionada amb la generació del graf en temps de compilació és molt escassa. Els compiladors estan limitats pel coneixement que poden extreure, que depèn de l’aplicació i del model de programació. La tercera contribució de la tesi és la generació d’un graf de dependències enriquit que pot ser interpretat pel sistema en temps d’execució de manera que el cost de resoldre les dependències sigui mínim. Amb les anteriors contribucions com a base per a determinar la seguretat funcional de OpenMP, la darrera contribució de la tesi consisteix en adaptar OpenMP a sistemes crítics, explorant dues direccions: 1) indicar com OpenMP es pot utilitzar de forma segura en un domini com, i 2) integrar OpenMP en Ada, un llenguatge molt utilitzat en el domini de seguretat.
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Karlsson, Sven. „Shared Memory and OpenMP on Clusters“. Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3831.
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Clusters, i.e., several computers interconnected with acommunication network, provide a cost efficient way to achievehigh performance. Messages are the natural way of communicationin this kind of systems. However, it is widely argued thatusing a shared memory programming model reduces the programmingeffort. Hence it is interestingto investigate systems thatprovide shared memory on clusters.
This thesis describes some performance aspects of providingsuch a shared memory using software. The systems that provide ashared memory in software are commonly called softwaredistributed shared memory systems, software DSM systems. Thethesis consists of seven papers that each describe differentaspects of software DSM systems.
One of the main performance bottlenecks is the communicationnetwork and three papers in the thesis investigates thisbottleneck. One paper analyzes the traffic sent on the networkwhen applications are executed. In another paper a latencyhiding technique is described and evaluated that substantiallyincreases the performance of iterative applications, i.e.,applications with loops. The last paper investigates the use ofpriorities to reduce the latency of certain messages used bythe software DSM system.
One paper is devoted to discussing how a portable softwareDSM system should be designed and this paper forms the basisfor the remaining three papers. These papers also present acompiler and run-time library for OpenMP which is a recentindustry shared memory programming model. The compiler and therun-time library were developed as part of the thesis. One ofthe three papers describes a prototype system for runningOpenMP applications on clusters. The second presents thecompiler and compares the performance of applications compiledwith the compiler with that of the applications compiled with acommercial compiler. The last paper describes the OpenMPrun-time library.
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Lorenzon, Arthur Francisco. „Aurora : seamless optimization of openMP applications“. reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/179828.
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A exploração eficiente do paralelismo no nível de threads tem sido um desafio para os desenvolvedores de softwares. Como muitas aplicações não escalam com o número de núcleos, aumentar cegamente o número de threads pode não produzir os melhores resultados em desempenho ou energia. No entanto, a tarefa de escolher corretamente o número ideal de threads não é simples: muitas variáveis estão envolvidas (por exemplo, saturação do barramento off-chip e sobrecarga de sincronização de dados), que mudam de acordo com diferentes aspectos do sistema (por exemplo, conjunto de entrada, micro-arquitetura) e mesmo durante a execução da aplicação. Para abordar esse complexo cenário, esta tese apresenta Aurora. Ela é capaz de encontrar automaticamente, em tempo de execução e com o mínimo de sobrecarga, o número ideal de threads para cada região paralela da aplicação e se readaptar nos casos em que o comportamento de uma região muda durante a execução. Aurora trabalha com o OpenMP e é completamente transparente tanto para o programador quanto para o usuário final: dado um binário de uma aplicação OpenMP, Aurora o otimiza sem nenhuma transformação ou recompilação de código. Através da execução de quinze benchmarks conhecidos em quatro processadores multi-core, mostramos que Aurora melhora o trade-off entre desempenho e energia em até: 98% sobre a execução padrão do OpenMP; 86% sobre o recurso interno do OpenMP que ajusta dinamicamente o número de threads; e 91% quando comparado a uma emulação do feedback-driven threading.Efficiently exploiting thread-level parallelism has been challenging for software developers. As many parallel applications do not scale with the number of cores, blindly increasing the number of threads may not produce the best results in performance or energy. However, the task of rightly choosing the ideal amount of threads is not straightforward: many variables are involved (e.g. off-chip bus saturation and overhead of datasynchronization), which will change according to different aspects of the system at hand (e.g., input set, micro-architecture) and even during execution. To address this complex scenario, this thesis presents Aurora. It is capable of automatically finding, at run-time and with minimum overhead, the optimal number of threads for each parallel region of the application and re-adapt in cases the behavior of a region changes during execution. Aurora works with OpenMP and is completely transparent to both designer and end-user: given an OpenMP application binary, Aurora optimizes it without any code transformation or recompilation. By executing fifteen well-known benchmarks on four multi-core processors, Aurora improves the trade-off between performance and energy by up to: 98% over the standard OpenMP execution; 86% over the built-in feature of OpenMP that dynamically adjusts the number of threads; and 91% over a feedback-driven threading emulation.
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af, Geijerstam Klas. „CONGESTION-CONTROLLED AUTOTUNING OF OPENMP PROGRAMS“. Thesis, Umeå universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-163181.
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Parallelisation is becoming more and more important as the single core performance increase is stagnating while the amount of cores is increasing with every new generation of hardware. The traditional approach of manual parallelisation has an alternative in parallel frameworks, such as OpenMP, which can simplify the creation of parallel code. Optimising this code can, however, be cumbersome and difficult. Automating the optimisation or tuning of parallel code and computations is a very interesting alternative to manually optimising algorithms and programs. Previous work has shown that intricate systems can effectively autotune parallel programs with potentially the same effectiveness as human experts. This study suggests using an approach with the main algorithm used inspired from the congestion control algorithms from computer networks, namely AIMD. By applying the algorithm on top of an OpenMP program the parallel parameters such as grain size can be controlled. Thee simplied algorithm is shown to be able to achieve a 19% speedup compared to a naive static parallel implementation
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Meinel, Christoph, und Christian Willems. „openHPI : das MOOC-Angebot des Hasso-Plattner-Instituts“. Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6680/.
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Die neue interaktive Online-Bildungsplattform openHPI (https://openHPI.de) des Hasso-Plattner-Instituts (HPI) bietet frei zugängliche und kostenlose Onlinekurse für interessierte Teilnehmer an, die sich mit Inhalten aus dem Bereich der Informationstechnologien und Informatik beschäftige¬n. Wie die seit 2011 zunächst von der Stanford University, später aber auch von anderen Elite-Universitäten der USA angeboten „Massive Open Online Courses“, kurz MOOCs genannt, bietet openHPI im Internet Lernvideos und weiterführenden Lesestoff in einer Kombination mit lernunterstützenden Selbsttests, Hausaufgaben und einem sozialen Diskussionsforum an und stimuliert die Ausbildung einer das Lernen fördernden virtuellen Lerngemeinschaft. Im Unterschied zu „traditionellen“ Vorlesungsportalen, wie z.B. dem tele-TASK Portal (http://www.tele-task.de), bei dem multimedial aufgezeichnete Vorlesungen zum Abruf bereit gestellt werden, bietet openHPI didaktisch aufbereitete Onlinekurse an. Diese haben einen festen Starttermin und bieten dann in einem austarierten Zeitplan von sechs aufeinanderfolgenden Kurswochen multimedial aufbereitete und wann immer möglich interaktive Lehrmaterialien. In jeder Woche wird ein Kapitel des Kursthemas behandelt. Dazu werden zu Wochenbeginn eine Reihe von Lehrvideos, Texten, Selbsttests und ein Hausaufgabenblatt bereitgestellt, mit denen sich die Kursteilnehmer in dieser Woche beschäftigen. Kombiniert sind die Angebote mit einer sozialen Diskussionsplattform, auf der sich die Teilnehmer mit den Kursbetreuern und anderen Teilnehmern austauschen, Fragen klären und weiterführende Themen diskutieren können. Natürlich entscheiden die Teilnehmer selbst über Art und Umfang ihrer Lernaktivitäten. Sie können in den Kurs eigene Beiträge einbringen, zum Beispiel durch Blogposts oder Tweets, auf die sie im Forum verweisen. Andere Lernende können diese dann kommentieren, diskutieren oder ihrerseits erweitern. Auf diese Weise werden die Lernenden, die Lehrenden und die angebotenen Lerninhalte in einer virtuellen Gemeinschaft, einem sozialen Lernnetzwerk miteinander verknüpft.The new interactive online educational platform openHPI, (https://openHPI.de) from Hasso Plattner Institute (HPI), offers freely accessible courses at no charge for all who are interested in subjects in the field of information technology and computer science. Since 2011, “Massive Open Online Courses,” called MOOCs for short, have been offered, first at Stanford University and then later at other U.S. elite universities. Following suit, openHPI provides instructional videos on the Internet and further reading material, combined with learning-supportive self-tests, homework and a social discussion forum. Education is further stimulated by the support of a virtual learning community. In contrast to “traditional” lecture platforms, such as the tele-TASK portal (http://www.tele-task.de) where multimedia recorded lectures are available on demand, openHPI offers didactic online courses. The courses have a fixed start date and offer a balanced schedule of six consecutive weeks presented in multimedia and, whenever possible, interactive learning material. Each week, one chapter of the course subject is treated. In addition, a series of learning videos, texts, self-tests and homework exercises are provided to course participants at the beginning of the week. The course offering is combined with a social discussion platform where participants have the opportunity to enter into an exchange with course instructors and fellow participants. Here, for example, they can get answers to questions and discuss the topics in depth. The participants naturally decide themselves about the type and range of their learning activities. They can make personal contributions to the course, for example, in blog posts or tweets, which they can refer to in the forum. In turn, other participants have the chance to comment on, discuss or expand on what has been said. In this way, the learners become the teachers and the subject matter offered to a virtual community is linked to a social learning network.
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Meinel, Christoph, und Christian Willems. „openHPI : the MOOC offer at Hasso Plattner Institute“. Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6717/.
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The new interactive online educational platform openHPI, (https://openHPI.de) from Hasso Plattner Institute (HPI), offers freely accessible courses at no charge for all who are interested in subjects in the field of information technology and computer science. Since 2011, “Massive Open Online Courses,” called MOOCs for short, have been offered, first at Stanford University and then later at other U.S. elite universities. Following suit, openHPI provides instructional videos on the Internet and further reading material, combined with learning-supportive self-tests, homework and a social discussion forum. Education is further stimulated by the support of a virtual learning community. In contrast to “traditional” lecture platforms, such as the tele-TASK portal (http://www.tele-task.de) where multimedia recorded lectures are available on demand, openHPI offers didactic online courses. The courses have a fixed start date and offer a balanced schedule of six consecutive weeks presented in multimedia and, whenever possible, interactive learning material. Each week, one chapter of the course subject is treated. In addition, a series of learning videos, texts, self-tests and homework exercises are provided to course participants at the beginning of the week. The course offering is combined with a social discussion platform where participants have the opportunity to enter into an exchange with course instructors and fellow participants. Here, for example, they can get answers to questions and discuss the topics in depth. The participants naturally decide themselves about the type and range of their learning activities. They can make personal contributions to the course, for example, in blog posts or tweets, which they can refer to in the forum. In turn, other participants have the chance to comment on, discuss or expand on what has been said. In this way, the learners become the teachers and the subject matter offered to a virtual community is linked to a social learning network.Die neue interaktive Online-Bildungsplattform openHPI (https://openHPI.de) des Hasso-Plattner-Instituts (HPI) bietet frei zugängliche und kostenlose Onlinekurse für interessierte Teilnehmer an, die sich mit Inhalten aus dem Bereich der Informationstechnologien und Informatik beschäftige¬n. Wie die seit 2011 zunächst von der Stanford University, später aber auch von anderen Elite-Universitäten der USA angeboten „Massive Open Online Courses“, kurz MOOCs genannt, bietet openHPI im Internet Lernvideos und weiterführenden Lesestoff in einer Kombination mit lernunterstützenden Selbsttests, Hausaufgaben und einem sozialen Diskussionsforum an und stimuliert die Ausbildung einer das Lernen fördernden virtuellen Lerngemeinschaft. Im Unterschied zu „traditionellen“ Vorlesungsportalen, wie z.B. dem tele-TASK Portal (http://www.tele-task.de), bei dem multimedial aufgezeichnete Vorlesungen zum Abruf bereit gestellt werden, bietet openHPI didaktisch aufbereitete Onlinekurse an. Diese haben einen festen Starttermin und bieten dann in einem austarierten Zeitplan von sechs aufeinanderfolgenden Kurswochen multimedial aufbereitete und wann immer möglich interaktive Lehrmaterialien. In jeder Woche wird ein Kapitel des Kursthemas behandelt. Dazu werden zu Wochenbeginn eine Reihe von Lehrvideos, Texten, Selbsttests und ein Hausaufgabenblatt bereitgestellt, mit denen sich die Kursteilnehmer in dieser Woche beschäftigen. Kombiniert sind die Angebote mit einer sozialen Diskussionsplattform, auf der sich die Teilnehmer mit den Kursbetreuern und anderen Teilnehmern austauschen, Fragen klären und weiterführende Themen diskutieren können. Natürlich entscheiden die Teilnehmer selbst über Art und Umfang ihrer Lernaktivitäten. Sie können in den Kurs eigene Beiträge einbringen, zum Beispiel durch Blogposts oder Tweets, auf die sie im Forum verweisen. Andere Lernende können diese dann kommentieren, diskutieren oder ihrerseits erweitern. Auf diese Weise werden die Lernenden, die Lehrenden und die angebotenen Lerninhalte in einer virtuellen Gemeinschaft, einem sozialen Lernnetzwerk miteinander verknüpft.
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Rocha, Andreia Patricia Ferreira da Silva. „OpenSim: um recurso didático no ensino do desenho“. Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14670.
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Mestrado em Ensino de Artes Visuais no 3º Ciclo do Ensino Básico e no Ensino SecundárioO relatório que aqui se apresenta é o resultado da investigação desenvolvida no âmbito do mestrado em ensino de artes visuais durante a Prática de Ensino Supervisionada, na disciplina de Desenho A, numa Escola de Ensino Artístico Especializado no Porto. A disciplina de Desenho A, nesta escola, ocupa um papel central, sendo uma disciplina comum a todos os cursos. Face às dificuldades apresentadas nos exercícios diagnósticos realizados pelos alunos no início da investigação e em virtude da presença da escola no mundo virtual OpenSim, estabeleceu-se a utilização desta plataforma como um recurso didático com interesse pedagógico. Tendo por base o enquadramento teórico que o fundamenta, este estudo teve como finalidade analisar e compreender as potencialidades educativas do mundo virtual OpenSim para a compreensão da perspetiva e da sua representação, no âmbito da disciplina de Desenho. A análise dos resultados obtidos indica que a utilização do OpenSim contribuiu positivamente para o processo do ensino e da aprendizagem do desenho.
This report is the result of the research conducted for the MA in Education in Visual Arts, under the Drawing A course subject supervised teaching practice, in a school of art education in Porto. In this school, Drawing A is a pivotal subject which is common to all courses. Due to student difficulties in diagnostic exercises at the beginning of research, and since the school had a presence in the OpenSim virtual world, this platform was established as a teaching resource with a pedagogical interest. Set against the theoretical framework underlying it, this study aimed at analysing and understanding the educational potential of the OpenSim virtual world as a means to understand perspective and its representation within the Drawing A course subject. The analysis of the results obtained indicates that the use of OpenSim has contributed positively for the process of teaching and learning how to draw.
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Porter, Jeremy. „Detecting Malicious Behavior in OpenWrt with QEMU Tracing“. Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1564840733498961.
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Volkmer, Toni. „OpenMP parallelization in the NFFT software library“. Universitätsbibliothek Chemnitz, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-94837.
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We describe an implementation of a multi-threaded NFFT (nonequispaced fast Fourier transform) software library and present the used parallelization approaches. Besides the NFFT kernel, the NFFT on the two-sphere and the fast summation based on NFFT are also parallelized. Thereby, the parallelization is based on OpenMP and the multi-threaded FFTW library. Furthermore, benchmarks for various cases are performed. The results show that an efficiency higher than 0.50 and up to 0.79 can still be achieved at 12 threads.
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Brettschneider, Ida. „THE USE OF TASK PRIORITIZATION IN OPENMP“. Thesis, Umeå universitet, Institutionen för datavetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-175882.
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As the hardware is evolving, the amount of cores increases and so does the use of parallel computing. Parallelizing a program is a way to increase the performance by distributing tasks across multiple threads or processors, taking advantage of the increasing amount of cores. An application programming interface that simplifies the usage of parallelism is OpenMP. OpenMP uses environment variables to inuence the runtime behavior and one such variable that will be analized in this study is OpenMP 45 Task Priority. This study analysis how Task Priority can be used for efficiently prioritizing computations to increase the execution time, and also the limitations of Task Priority. The study shows that Task Priority can improve the performance of a program by prioritizing the execution of some tasks before others.
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Dandapanthula, Nishanth. „InfiniBand Network Analysis and Monitoring using OpenSM“. The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313422543.
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Luks, Jesper. „Automation för att skapa klientkonfigurationer : för OpenVPN med PiVPN“. Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39377.
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Våren år 2020 spred sig viruset COVID-19 över hela världen. Detta ledde till att behovet att arbeta hemifrån ökade. Ett verktyg för att utföra sitt arbete hemifrån kan vara en VPN-anslutning. Med VPN-anslutningen är det möjligt att hemifrån ansluta till arbetsplatsens lokala nätverk och komma åt de resurser som finns där. Detta arbete beskriver kortfattat om VPN-teknologin OpenVPN och hur det använder certifikat för autentisering av klient och server. Det har även utvecklats ett skript som skapar klientkonfigurationer. Dessa konfigurationsfiler gör det möjligt att ansluta till en OpenVPN-server. Ett av de verktyg som används för att skapa en konfigurationsfil i detta arbete är PiVPN. PiVPN utvecklas och underhålls av användare på GitHub. Informationen som skriptet använder sig av för att skapa konfigurationsfiler kommer från en CSV-fil. Tester visar att det utvecklade skriptet är snabbare och mer effektivt än nuvarande tillgängliga metoder. Då det valda skriptspråket inte är anpassat för bearbetning av filinnehåll borde det kanske ha varit ett annat.
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Jašíček, Petr. „Softwarový kontrolér Wi-Fi přístupových bodů se systémem OpenWrt“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-400887.
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The aim of this thesis was to create a web application used for centralized management and configuration of wireless networks on access points running on OpenWrt distribution. The reader is acquainted with common principles of wireless networks including description of existing solutions for their centralized management. After that the thesis introduces the reader to OpenWrt distribution and to a method of its configuration using UCI model. The reader is then introduced to the main technologies used in this thesis. Author further describes architecture, user interface and implementation of the web application. The created web application is platform agnostic and provides easy way to manage and configure access points with OpenWrt distribution.
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McLaughlin, Jared D. „Parallel Processing of Reactive Transport Models Using OpenMP“. Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2328.pdf.
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Ribeiro, Hethini do Nascimento. „Paralelização do algoritmo DIANA com OpenMP e MPI“. Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/157280.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
No início desta década havia cerca de 5 bilhões de telefones em uso gerando dados. Essa produção global aumentou aproximadamente 40% ao ano no início da década passada. Esses grandes conjuntos de dados que podem ser capturados, comunicados, agregados, armazenados e analisados, também chamados de Big Data, estão colocando desafios inevitáveis em muitas áreas e, em particular, no campo Machine Learning. Algoritmos de Machine Learning são capazes de extrair informações úteis desses grandes repositórios de dados e por este motivo está se tornando cada vez mais importante o seu estudo. Os programas aptos a realizarem essa tarefa podem ser chamados de algoritmos de classificação e clusterização. Essas aplicações são dispendiosas computacionalmente. Para citar alguns exemplos desse custo, o algoritmo Quality Threshold Clustering tem, no pior caso, complexidade O(�������������5). Os algoritmos hierárquicos AGNES e DIANA, por sua vez, possuem O(n²) e O(2n) respectivamente. Sendo assim, existe um grande desafio, que consiste em processar grandes quantidades de dados em um período de tempo realista, encorajando o desenvolvimento de algoritmos paralelos que se adequam ao volume de dados. O objetivo deste trabalho é apresentar a paralelização do algoritmo de hierárquico divisivo DIANA. O desenvolvimento do algoritmo foi realizado em MPI e OpenMP, chegando a ser três vezes mais rápido que a versão monoprocessada, evidenciando que embora em ambientes de memória distribuídas necessite de sincronização e troca de mensagens, para um certo grau de paralelismo é vantajosa a aplicação desse tipo de otimização para esse algoritmo.
Earlier in this decade there were about 5 billion phones in use generating data. This global production increased approximately 40% per year at the beginning of the last decade. These large datasets that can be captured, communicated, aggregated, stored and analyzed, also called Big Data, are posing inevitable challenges in many areas, and in particular in the Machine Learning field. Machine Learning algorithms are able to extract useful information from these large data repositories and for this reason their study is becoming increasingly important. The programs that can perform this task can be called classification and clustering algorithms. These applications are computationally expensive. To cite some examples of this cost, the Quality Threshold Clustering algorithm has, in the worst case, complexity O (n5). The hierarchical algorithms AGNES and DIANA, in turn, have O (n²) and O (2n) respectively. Thus, there is a great challenge, which is to process large amounts of data in a realistic period of time, encouraging the development of parallel algorithms that fit the volume of data. The objective of this work is to present the parallelization of the DIANA divisive hierarchical algorithm. The development of the algorithm was performed in MPI and OpenMP, reaching three times faster than the monoprocessed version, evidencing that although in distributed memory environments need synchronization and exchange of messages, for a certain degree of parallelism it is advantageous to apply this type of optimization for this algorithm.
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Garlet, Milani Luís Felipe. „Autotuning assisté par apprentissage automatique de tâches OpenMP“. Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALM022.
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Les architectures informatiques modernes sont très complexes, nécessitant un grand effort de programmation pour obtenir toute la performance que le matériel est capable de fournir. En effet, alors que les développeurs connaissent les optimisations potentielles, la seule façon possible de dire laquelle est le plus rapide pour une plate-forme est de le tester. En outre, les nombreuses différences entre deux plates-formes informatiques, dans le nombre de cœurs, les tailles de cache, l'interconnexion, les fréquences de processeur et de mémoire, etc, rendent très difficile la bonne exécution du même code sur plusieurs systèmes. Pour extraire le plus de performances, il est souvent nécessaire d'affiner le code pour chaque système. Par conséquent, les développeurs adoptent l'autotuning pour atteindre un certain degré de performance portable. De cette façon, les optimisations potentielles peuvent être spécifiées une seule fois et, après avoir testé chaque possibilité sur une plate-forme, obtenir une version haute performance du code pour cette plate-forme particulière. Toutefois, cette technique nécessite de régler chaque application pour chaque plate-forme quelle cible. Non seulement cela prend du temps, mais l'autotuning et l'exécution réelle de l'application diffèrent. Des différences dans les données peuvent déclencher un comportement différent, ou il peut y avoir différentes interactions entre les fils dans l'autotuning et l'exécution réelle. Cela peut conduire à des décisions sous-optimales si l'autotuner choisit une version qui est optimale pour la formation, mais pas pour l'exécution réelle de l'application. Nous proposons l'utilisation d'autotuning pour sélectionner les versions du code pertinentes pour une gamme de plates-formes et, lors de l'exécution de l'application, le système de temps d'exécution identifie la meilleure version à utiliser à l'aide de l'une des trois politiques que nous proposons: Mean, Upper Confidence Bound et Gradient Bandit. De cette façon, l'effort de formation est diminué et il permet l'utilisation du même ensemble de versions avec différentes plates-formes sans sacrifier les performances. Nous concluons que les politiques proposées peuvent identifier la version à utiliser sans subir de pertes de performance substantielles. De plus, lorsque l'utilisateur ne connaît pas suffisamment de détails de l'application pour configurer de manière optimale la politique d'exploration puis de validation utilisée par d'autres systèmes de temps d'exécution, la politique UCB plus adaptable peut être utilisée à sa placeModern computer architectures are highly complex, requiring great programming effort to obtain all the performance the hardware is capable of delivering. Indeed, while developers know potential optimizations, the only feasible way to tell which of them is faster for some platform is to test it. Furthermore, the many differences between two computer platforms, in the number of cores, cache sizes, interconnect, processor and memory frequencies, etc, makes it very challenging to have the same code perform well over several systems. To extract the most performance, it is often necessary to fine-tune the code for each system. Consequently, developers adopt autotuning to achieve some degree of portable performance. This way, the potential optimizations can be specified once, and, after testing each possibility on a platform, obtain a high-performance version of the code for that particular platform. However, this technique requires tuning each application for each platform it targets. This is not only time consuming but the autotuning and the real execution of the application differ. Differences in the data may trigger different behaviour, or there may be different interactions between the threads in the autotuning and the actual execution. This can lead to suboptimal decisions if the autotuner chooses a version that is optimal for the training but not for the real execution of the application. We propose the use of autotuning for selecting versions of the code relevant for a range of platforms and, during the execution of the application, the runtime system identifies the best version to use using one of three policies we propose: Mean, Upper Confidence Bound, and Gradient Bandit. This way, training effort is decreased and it enables the use of the same set of versions with different platforms without sacrificing performance. We conclude that the proposed policies can identify the version to use without incurring substantial performance losses. Furthermore, when the user does not know enough details of the application to configure optimally the explore-then-commit policy usedy by other runtime systems, the more adaptable UCB policy can be used in its place
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Sardar, Raham, und Usman Fazal. „Quality Assurance Techniques in OpenUP (Open Unified Process)“. Thesis, Linköpings universitet, Institutionen för datavetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-67579.
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Agile methods change the software processes. Agile processes such as Scrum, ExtremeProgramming (XP), Open Unified Process (OpenUP) etc. have techniques that improve softwarequality. No doubt that the purpose of these techniques is to inject quality assurance into theproject under development. This thesis presents quality assurance techniques in Open UnifiedProcess (OpenUP) along with comparative study to extreme programming (XP) for agilesoftware development. OpenUP is an agile and unified process that contains the minimal set ofpractices that help teams to be more effective in developing software. It assists to achieve qualityby an iterative and incremental approach with artifacts, checklists, guidelines, disciplines androles. On the other side XP emphasizes on values such as communication, feedback, respect,and courage. In addition, XP prescribes a collection of techniques, which aim to improvesoftware quality. Both these processes have the same purpose, to develop software that meets the stakeholder’sneeds and expectations, however they uses different approaches to achieve their goals. Thisthesis compares both processes in four different points of view, by comparing their qualitytechniques, focus in time, and cost of usage and social perspective. We have proposed an extrarole of the quality coordinator (QC) in OpenUP/XP. QC can support and coordinate project inall quality assurance activities. The objective of an extra role is to use the knowledge of QC toachieve highest possible product quality in software development process.Keywords: Agile Development, Quality assurance (QA), Open unified process (OpenUP),extreme programming (XP), Quality coordinator (QC)
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Swahn, Henrik. „Pthreads and OpenMP : A performance and productivity study“. Thesis, Blekinge Tekniska Högskola, Institutionen för programvaruteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12741.
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Today most computer have a multicore processor and are depending on parallel execution to be able to keep up with the demanding tasks that exist today, that forces developers to write software that can take advantage of multicore systems. There are multiple programming languages and frameworks that makes it possible to execute the code in parallel on different threads, this study looks at the performance and effort required to work with two of the frameworks that are available to the C programming language, POSIX Threads(Pthreads) and OpenMP. The performance is measured by paralleling three algorithms, Matrix multiplication, Quick Sort and calculation of the Mandelbrot set using both Pthreads and OpenMP, and comparing first against a sequential version and then the parallel version against each other. The effort required to modify the sequential program using OpenMP and Pthreads is measured in number of lines the final source code has. The results shows that OpenMP does perform better than Pthreads in Matrix Multiplication and Mandelbrot set calculation but not on Quick Sort because OpenMP has problem with recursion and Pthreads does not. OpenMP wins the effort required on all the tests but because there is a large performance difference between OpenMP and Pthreads on Quick Sort OpenMP cannot be recommended for paralleling Quick Sort or other recursive programs.
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Karcher, René. „Virtualisierte DMZ auf Xen-Basis OpenQRM und Xen als Partner“. Hamburg Diplomica-Verl, 2007. http://d-nb.info/989529673/04.
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Karcher, René. „Virtualisierte DMZ auf Xen-Basis : OpenQRM und Xen als Partner /“. Hamburg : Diplomica Verl, 2008. http://www.diplom.de/katalog/arbeit/11199.
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Arif, M. (Muhammad). „OpenEPC Integration within 5GTN as an NFV proof of concept“. Master's thesis, University of Oulu, 2017. http://jultika.oulu.fi/Record/nbnfioulu-201706082638.
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Abstract. Gone are the days, when a hardware is changed on every malfunctioning and the whole operation either stays down or load on the replacing hardware becomes too much which ultimately compromises the QoS. The IT industry is mature enough to tackle problems regarding scalability, space utilization, energy consumption, cost, agility and low availability. The expected throughput and network latency with 5G in the cellular Telecommunication Networks seems to be unachievable with the existing architecture and resources. Network Function Virtualization promises to merge IT and Telecommunications in such an efficient way that the expected results could be achieved no longer but sooner. The thesis work examines the compatibility and flexibility of a 3GPP virtual core network in a virtualization platform. The testbed is established on an LTE (Long Term Evolution) based network being already deployed and OpenEPC is added as virtual core network on it. The integration of OpenEPC in 5GTN (5TH Generation Test Network) is discussed in details in the thesis which will give an account of the possibility of implementing such a simulated vEPC (Virtual Evolved Packet Core) in a real network platform. The deployed setup is tested to check its feasibility and flexibility for a platform which could be used for NFV deployment in future. The monitoring of OpenEPC’s individual components while utilizing the major resources within them, forms the primary performance test. The CPU Load and Memory Utilization is tested on different CPU stress levels having a constant data traffic from actual UEs. At the completion of the thesis work, a consensus is built up based on the test results that the test setup can hold number of subscribers to a certain amount without any performance degradation. Moreover, the virtual core network throughput and network latency is also compared to the commercial LTE networks and theoretical maximum values on similar resources to check performance consistency OpenEPC must offer.
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Nilsson, Simon. „Remote measuring and logging : Evaluation of the Quectel OpenCPU technology“. Thesis, Mittuniversitetet, Avdelningen för data- och systemvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-25400.
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The company Sensefarm develops in the field of precision agriculture, more specifically a product for measuring and logging information on local environmental conditions. The collected data is transmitted to a remote server using GSM technology. They are looking into ways to improve their product. The purpose of this project is to evaluate the M66 GSM module and the accompanied OpenCPU technology. In the current product the GSM module is only used for the communication with the server. All other processing is done by a dedicated processor. The OpenCPU technology allows for running customized firmware on the GSM module, possibly allowing it to take over the responsibilities of the dedicated processor. An application implementing all the necessary functionality was developed to test this capability. The finished application was able to fulfill all the requirements specified, although it was not able to be tested in the field.
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Cargnelli, Matthieu. „OpenWP : étude et extension des technologies de Workflows pour le calcul haute performance sur grille“. Paris 11, 2008. http://www.theses.fr/2008PA112265.
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Cette thèse s’inscrit dans un contexte industriel. Elle aborde la problématique du passage de code de calcul scientifique séquentiel à un code de calcul exécutable sur une grille. L’approche proposée dans cette thèse exploite les technologies de worflows pour leur adéquation avec les problèmes rencontrés sur une grille. Après avoir présenté les solutions existantes pour exécuter un workflow sur une grille et une solution pour paralléliser un code séquentiel : openMP, l’auteur présente sa proposition : OpenWP. OpenWP est un environnement proposant un langage d’annotation de code séquentiel à base de directives en vue de sa transformation en workflow, puis le contrôle de l’exécution de ce worflow à travers un moteur tierce partie sur la grille. Un mécanisme de mémoire distribuée virtuellement partagée est proposé. Le langage défini pour OpenWP est détaillé, son expressivité critiquée et comparée à celle d’OpenMP. La conception d’OpenWP est ensuite décrite, ainsi que les choix technologiques qui ont conduit à l’implémentation d’un prototype. La thèse se poursuit par une validation de concept et une série d’évaluations de performances d’OpenWP avec plusieurs applications, dont un mailleur industriel utilisé par EADS. Enfin un système hybride combinant OpenWP et OpenMP est décrit. Ce système doit permettre à OpenWP d’exploiter la hiérarchie de la grille en utilisant les machines multi-processeurs à mémoire partagée lorsque cela est possible, avec OpenMP. Une preuve de concept est apportée sur un cas test simpleThis thesis has been conduced in an industrial context. It studies the code refactoring from a sequential scientific code into a grid enabled program. The proposed approach is based on the workflow technologies which are well suited for grid. After a presentation of existing solutions for workflow execution on the grid as well as a solution for code parallelization (openMP), the author presents his proposition : OpenWP. OpenWP is a workflow definition language based on directives to turn a sequential code into a workflow. OpenWP allows the controlled execution of this workflow on the grip using a third party workflow enactment engine. A distributed virtually shared memory system is proposed. The defined language is presented in detail and its expressivity is criticized and compared to OpenMP’s. The conception of OpenWP is then described and the technology choices made are explained. A prototype is presented. The document then shows a proof of concept and a series of performance evaluation of OpenWP used on few programs, among which an industrial mesher used by EADS. An hybrid system based on OpenWP and OpenMP is also described. This system must give OpenWP the ability to exploit the resource hierarchy found in the grid, by using the shared memory multi-processors machines whenever possible through OpenMP. A proof of concept test case is provided and commented
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Costa, Prats Juan José. „Efficient openMP over sequentially consistent distributed shared memory systems“. Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/81012.
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Nowadays clusters are one of the most used platforms in High Performance Computing and most programmers use the Message Passing Interface (MPI) library to program their applications in these distributed platforms getting their maximum performance, although it is a complex task. On the other side, OpenMP has been established as the de facto standard to program applications on shared memory platforms because it is easy to use and obtains good performance without too much effort.
So, could it be possible to join both worlds? Could programmers use the easiness of OpenMP in distributed platforms? A lot of researchers think so. And one of the developed ideas is the distributed shared memory (DSM), a software layer on top of a distributed platform giving an abstract shared memory view to the applications. Even though it seems a good solution it also has some inconveniences. The memory coherence between the nodes in the platform is difficult to maintain (complex management, scalability issues, high overhead and others) and the latency of the remote-memory accesses which can be orders of magnitude greater than on a shared bus due to the interconnection network.
Therefore this research improves the performance of OpenMP applications being executed on distributed memory platforms using a DSM with sequential consistency evaluating thoroughly the results from the NAS parallel benchmarks.
The vast majority of designed DSMs use a relaxed consistency model because it avoids some major problems in the area. In contrast, we use a sequential consistency model because we think that showing these potential problems that otherwise are hidden may allow the finding of some solutions and, therefore, apply them to both models.
The main idea behind this work is that both runtimes, the OpenMP and the DSM layer, should cooperate to achieve good performance, otherwise they interfere one each other trashing the final performance of applications.
We develop three different contributions to improve the performance of these applications: (a) a technique to avoid false sharing at runtime, (b) a technique to mimic the MPI behaviour, where produced data is forwarded to their consumers and, finally, (c) a mechanism to avoid the network congestion due to the DSM coherence messages. The NAS Parallel Benchmarks are used to test the contributions.
The results of this work shows that the false-sharing problem is a relative problem depending on each application. Another result is the importance to move the data flow outside of the critical path and to use techniques that forwards data as early as possible, similar to MPI, benefits the final application performance.
Additionally, this data movement is usually concentrated at single points and affects the application performance due to the limited bandwidth of the network. Therefore it is necessary to provide mechanisms that allows the distribution of this data through the computation time using an otherwise idle network.
Finally, results shows that the proposed contributions improve the performance of OpenMP applications on this kind of environments.
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Castellanos, Carrazana Abel. „Performance model for hybrid MPI+OpenMP master/worker applications“. Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/283403.
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En el entorno actual, diversas ramas de las ciencias, tienen la necesidad de auxiliarse de la computación de altas prestaciones para la
obtención de resultados a relativamente corto plazo. Ello es debido fundamentalmente, al alto volumen de información que necesita ser
procesada y también al costo computacional que demandan dichos cálculos. El beneficio al realizar este procesamiento de manera distribuida y
paralela, logra acortar de manera notable los tiempos de espera en la obtención de los resultados.
Para soportar ello, existen fundamentalmente dos modelos de programación ampliamente extendidos: el modelo de paso de mensajes a través de
librerías basadas en el estándar MPI, y el de memoria compartida con la utilización de OpenMP. Las aplicaciones híbridas son aquellas que
combinan ambos modelos con el fin de aprovechar en cada caso, las potencialidades específicas del paralelismo en cada uno. Lamentablemente,
la práctica ha demostrado que la utilización de esta combinación de modelos, no garantiza necesariamente una mejoría en el comportamiento de
las aplicaciones. Existen varios parámetros que deben ser considerados a determinar la configuración de la aplicación que proporciona el mejor
tiempo de ejecución. El número de proceso que se debe utilizar, el número de hilos en cada nodo, la distribución de datos entre procesos e hilos,
y así sucesivamente, son parámetros que afectan seriamente elrendimiento de
la aplicación. El valor apropiado de tales parámetros depende, por una parte, de las características de arquitectura del sistema
(latencia de las comunicaciones, el ancho de banda de comunicación, el tamaño y la distribución de los niveles de memoria cache,
la capacidad de cómputo, etc.) y, por otro lado, de la características propias del comportamiento de la aplicación.
La contribución fundamental de esta tesis radica en la utilización de una técnica novedosa para la predicción del rendimiento y la
eficiencia de aplicaciones híbridas de tipo Master/Worker. En particular, dentro del mundo del aprendizaje automatizado, este método de
predicción es conocido como arboles de regresión basados en modelos análiticos. Los resultados experimentales obtenidos permiten ser
optimista en cuanto al uso de este algoritmo para la predicción de ambas métricas o para la selección de la mejor configuración de
parámetros de ejecución de la aplicación.In the current environment, various branches of science are in need of auxiliary high-performance computing to obtain relatively short-term results. This is mainly due to the high volume of information that needs to be processed and the computational cost demanded by these calculations. The benefit to performing this processing using distributed and parallel programming mechanisms is that it achieves shorter waiting times in obtaining the results. To support this, there are basically two widespread programming models: the model of message passing based on the standard libraries MPI and the shared memory model with the use of OpenMP. Hybrid applications are those that combine both models in order to take the specific potential of parallelism of each one in each case. Unfortunately, experience has shown that using this combination of models does not necessarily guarantee an improvement in the behavior of applications. There are several parameters that must be considered to determine the configuration of the application that provides the best execution time. The number of process that must be used,the number of threads on each node, the data distribution among processes and threads, and so on, are parameters that seriously affect the performance of the application. On the one hand, the appropriate value of such parameters depends on the architectural features of the system (communication latency, communication bandwidth, cache memory size and architecture, computing capabilities, etc.), and, on the other hand, on the features of the application. The main contribution of this thesis is a novel technique for predicting the performance and efficiency of parallel hybrid Master/Worker applications. This technique is known as model-based regression trees into the field of machine learning. The experimental results obtained allow us to be optimistic about the use of this algorithm for predicting both metrics and to select the best application execution parameters.
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Larsgård, Nils Magnus. „Parallelizing Particle-In-Cell Codes with OpenMP and MPI“. Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8722.
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Today's supercomputers often consists of clusters of SMP nodes. Both OpenMP and MPI are programming paradigms that can be used for parallelization of codes for such architectures. OpenMP uses shared memory, and hence is viewed as a simpler programming paradigm than MPI that is primarily a distributed memory paradigm. However, the Open MP applications may not scale beyond one SMP node. On the other hand, if we only use MPI, we might introduce overhead in intra-node communication. In this thesis we explore the trade-offs between using OpenMP, MPI and a mix of both paradigms for the same application. In particular, we look at a physics simulation and parallalize it with both OpenMP and MPI for large-scale simulations on modern supercomputers. A parallel SOR solver with OpenMP and MPI is implemented and the effects of such hybrid code are measured. We also utilize the FFTW-library that includes both system-optimized serial implementations and a parallel OpenMP FFT implementation. These solvers are used to make our existing Particle-In-Cell codes be more scalable and compatible with current programming paradigms and supercomputer architectures. We demonstrate that the overhead from communications in OpenMP loops on an SMP node is significant and increases with the number of CPUs participating in execution of the loop compared to equivalent MPI implementations. To analyze this result, we also present a simple model on how to estimate the overhead from communication in OpenMP loops. Our results are both surprising and should be of great interest to a large class of parallel applications.
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Örtenberg, Alexander. „Parallelization of DIRA and CTmod Using OpenMP and OpenCL“. Thesis, Linköpings universitet, Informationskodning, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-119183.
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Parallelization is the answer to the ever-growing demands of computing power by taking advantage of multi-core processor technology and modern many-core graphics compute units. Multi-core CPUs and many-core GPUs have the potential to substantially reduce the execution time of a program but it is often a challenging task to ensure that all available hardware is utilized. OpenMP and OpenCL are two parallel programming frameworks that have been developed to allow programmers to focus on high-level parallelism rather than dealing with low-level thread creation and management. This thesis applies these frameworks to the area of computed tomography by parallelizing the image reconstruction algorithm DIRA and the photon transport simulation toolkit CTmod. DIRA is a model-based iterative reconstruction algorithm in dual-energy computed tomography, which has the potential to improve the accuracy of dose planning in radiation therapy. CTmod is a toolkit for simulating primary and scatter projections in computed tomography to optimize scanner design and image reconstruction algorithms. The results presented in this thesis show that parallelization combined with computational optimization substantially decreased execution times of these codes. For DIRA the execution time was reduced from two minutes to just eight seconds when using four iterations and a 16-core CPU so a speedup of 15 was achieved. CTmod produced similar results with a speedup of 14 when using a 16-core CPU. The results also showed that for these particular problems GPU computing was not the best solution.
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Albalawi, Eid. „Task Level Parallelization of Irregular Computations using OpenMP 3.0“. atlantis press, 2013. http://hdl.handle.net/1993/23321.
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OpenMP is a standard parallel programming language used
to develop parallel applications on shared memory machines.
OpenMP is very suitable for designing parallel
algorithms for regular applications where the amount of work
is known apriori and therefore distribution of work
among the threads can be done at compile time.
In irregular applications, the load
changes dynamically at runtime and distribution of work among the threads
can only be done at runtime. In the literature, it has been
shown that OpenMP produces unsatisfactory performance for
irregular applications.
In 2008, the OpenMP 3.0 version introduced new directives and features such as the ''task'' directive
to handle irregular computations. Not much work
has gone into studying irregular algorithms in OpenMP 3.0.
In this thesis, I provide some insight into the usefulness of OpenMP 3.0
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Klemm, Michael. „Reparallelization and migration of OpenMP applications in grid environments“. Aachen Shaker, 2008. http://d-nb.info/993156533/04.
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Olofsson, Simon, und Emrik Olsson. „Analyzing OpenMP Parallelization Capabilities and Finding Thread Handling Optimums“. Thesis, Högskolan Väst, Avdelningen för Matematik, Data- och Lantmäteriteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-12752.
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Utmaningar i modern processortillverkning begränsar klockfrekvensen för enkeltrådiga applikationer, vilket har resulterat i utvecklingen av flerkärniga processorer. Dessa processorer tillåter flertrådig exekvering och ökar därmed prestandan. För att undersöka möjligheterna med parallell exekvering används en Fast Fourier Transform algoritm där trådprestanda mäts för olika skapade tester med varierande problemstorlekar. Dessa tester körs på tre testsystem och använder olika sökalgoritmer för att dynamiskt justera antalet trådar vid exekvering. Denna prestanda jämförs sedan med den högsta möjliga prestanda som kan fås genom Brute-Forcing. Testerna använder OpenMP-instruktioner för att specificera antalet trådar som finns tillgängliga för programexekvering. För mindre problemstorlekar resulterar färre antal trådar i högre prestanda. Motsatsen gäller för större problemstorlekar, där många trådar föredras istället. Denna rapport visar att användning av alla tillgängliga trådar för ett system inte är optimalt i alla lägen då det finns en tydlig koppling mellan problemstorlek och det optimala antalet trådar för maximal prestanda. Detta gäller för alla tre testsystem som omfattas av rapporten. Metodiken som har använts för att skapa testerna har gjort det möjligt att dynamiskt kunna justera antalet trådar vid exekvering. Rapporten visar också att dynamisk justering av antalet trådar inte passar för alla typer av applikationer.As physical limitations limit the clock frequencies available for a single thread, processor vendors increasingly build multi-core systems with support for dividing processes across multiple threads for increased overall processing power. To examine parallelization capabilities, a fast fourier transform algorithm is used to benchmark parallel execution and compare brute-forced optimum with results from various search algorithms and scenarios across three different testbed systems. These algorithms use OpenMP instructions to directly specify number of threads available for program execution. For smaller problem sizes the tests heavily favour fewer threads, whereas the larger problems favour the native 'maximum' thread count. Several algorithms were used to compare ways of searching for the optimum thread values at runtime. We showed that running at maximum threads is not always the most optimum choice as there is a clear relationship between the problem size and the optimal thread-count in the experimental setup across all three machines. The methods used also made it possible to identify a way to dynamically adjust the thread-count during runtime of the benchmark, however it is not certain all applications would be suitable for this type of dynamic thread assignment
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Wottrich, Rodolfo Guilherme 1990. „Loop parallelization in the cloud using OpenMP and MapReduce“. [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/275500.
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Orientadores: Guido Costa Souza de Araújo, Rodolfo Jardim de AzevedoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação
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Resumo: A busca por paralelismo sempre foi um importante objetivo no projeto de sistemas computacionais, conduzida principalmente pelo constante interesse na redução de tempos de execução de aplicações. Programação paralela é uma área de pesquisa ativa, na qual o interesse tem crescido devido à emergência de arquiteturas multicore. Por outro lado, aproveitar as grandes capacidades de computação e armazenamento da nuvem e suas características desejáveis de flexibilidade e escalabilidade oferece várias oportunidades interessantes para abordar problemas de pesquisa relevantes em computação científica. Infelizmente, em muitos casos a implementação de aplicações na nuvem demanda conhecimento específico de interfaces de programação paralela e APIs, o que pode se tornar um fardo na programação de aplicações complexas. Para superar tais limitações, neste trabalho propomos OpenMR, um modelo de execução baseado na sintaxe e nos princípios da API OpenMP que facilita a tarefa de programar sistemas distribuídos (isto é, clusters locais ou a nuvem remota). Especificamente, este trabalho aborda o problema de executar a paralelização de laços, usando OpenMR, em um ambiente distribuído, através do mapeamento de iterações do laço para nós MapReduce. Assim, a interface de programação para a nuvem se torna a própria linguagem, livrando o desenvolvedor da tarefa de se preocupar com detalhes da distribuição de cargas de trabalho e dados. Para avaliar a validade da proposta, modificamos benchmarks da suite SPEC OMP2012 para se encaixarem no modelo proposto, desenvolvemos outros toy benchmarks que são I/O-bound e executamo-os em duas configurações: (a) um cluster de computadores disponível localmente através de uma LAN padrão; e (b) clusters disponíveis remotamente através dos serviços Amazon AWS. Comparamos os resultados com a execução utilizando OpenMP em uma arquitetura SMP e mostramos que a técnica de paralelização proposta é factível e demonstra boa escalabilidade
Abstract: The pursuit of parallelism has always been an important goal in the design of computer systems, driven mainly by the constant interest in reducing program execution time. Parallel programming is an active research area, which has grown in interest due to the emergence of multicore architectures. On the other hand, harnessing the large computing and storage capabilities of the cloud and its desirable flexibility and scaling features offers a number of interesting opportunities to address some relevant research problems in scientific computing. Unfortunately, in many cases the implementation of applications on the cloud demands specific knowledge of parallel programming interfaces and APIs, which may become a burden when programming complex applications. To overcome such limitations, in this work we propose OpenMR, an execution model based on the syntax and principles of the OpenMP API which eases the task of programming distributed systems (i.e. local clusters or remote cloud). Specifically, this work addresses the problem of performing loop parallelization, using OpenMR, in a distributed environment, through the mapping of loop iterations to MapReduce nodes. By doing so, the cloud programming interface becomes the programming language itself, freeing the developer from the task of worrying about the details of distributing workload and data. To assess the validity of the proposal, we modified benchmarks from the SPEC OMP2012 suite to fit the proposed model, developed other I/O-bound toy benchmarks and executed them in two settings: (a) a computer cluster locally available through a standard LAN; and (b) clusters remotely available through the Amazon AWS services. We compare the results to the execution using OpenMP in an SMP architecture and show that the proposed parallelization technique is feasible and demonstrates good scalability
Mestrado
Ciência da Computação
Mestre em Ciência da Computação
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Berkenbrock, Gian Ricardo. „OpenUP extension for development of wireless sensor network applications“. Instituto Tecnológico de Aeronáutica, 2010. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=1132.
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This work presents an extension for OpenUP software development process, which includes the disciplines of Simulation and Prototyping for developing WSN applications. The simulation discipline was created to address performance, scalability, and integration requirements in the software development process for WSN application. The prototyping discipline was created in order to improve the knowledge about the system as well as to refine information about the system gathered from simulation study. We also describe the integration of both disciplines with OpenUP based on work products. A WSN application was developed in order to illustrate the use of the proposed disciplines. The WSN application monitors the environmental conditions required to age a sugar cane spirits. During the execution, the effort and time required to perform each activity is measured. We also performed a simulation study to investigate how proposed disciplines influence the software development process. A simulator based on discrete simulation approach is described and some experiments are performed, generating valuable results. Experiments with different team sizes and process models are performed and described. And their results are illustrated.
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Liu, Yuwei. „OpenMP based Action Entropy Active Sensing in Cloud Computing“. Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1584809369789769.
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Broquedis, François. „De l’exécution structurée d’applications scientifiques OpenMP sur architectures hiérarchiques“. Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14190/document.
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Le domaine applicatif de la simulation numérique requiert toujours plus de puissance de calcul. La technologie multicœur aide à satisfaire ces besoins mais impose toutefois de nouvelles contraintes aux programmeurs d’applications scientifiques qu’ils devront respecter s’ils souhaitent en tirer la quintessence. En particulier, il devient plus que jamais nécessaire de structurer le parallélisme des applications pour s’adapter au relief imposé par la hiérarchie mémoire des architectures multicœurs. Les approches existantes pour les programmer ne tiennent pas compte de cette caractéristique, et le respect de la structure du parallélisme reste à la charge du programmeur. Il reste de ce fait très difficile de développer une application qui soit à la fois performante et portable.La contribution de cette thèse s’articule en trois axes. Il s’agit dans un premier temps de s’appuyer sur le langage OpenMP pour générer du parallélisme structuré, et de permettre au programmeur de transmettre cette structure au support exécutif ForestGOMP. L’exécution structurée de ces flots de calcul est ensuite laissée aux ordonnanceurs Cacheet Memory développés au cours de cette thèse, permettant respectivement de maximiser la réutilisation des caches partagés et de maximiser la bande passante mémoire accessible par les programmes OpenMP. Enfin, nous avons étudié la composition de ces ordonnanceurs, et plus généralement de bibliothèques parallèles, en considérant cette voie comme une piste sérieuse pour exploiter efficacement les multiples unités de calcul des architectures multicœurs.Les gains obtenus sur des applications scientifiques montrent l’intérêt d’une communication forte entre l’application et le support exécutif, permettant l’ordonnancement dynamique et portable de parallélisme structuré sur les architectures hiérarchiquesAbstract
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Guled, Pavan. „Analysis of the physical interaction between Human and Robot via OpenSim software“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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The purpose of this thesis is to analyse the Physical Human-Robot Interaction (PHRI) which is an important extension of traditional HRI work. This work of analysis helps in understanding the effects on the upper limb of the human musculoskeletal system when human user interacts with the robotic device. This is concerned for various applicational interests, like in the field of health care, industrial applications, military, sport science and many more.
We developed a CAD model of an exoskeleton in SolidWorks to satisfy all the properties required. The designed upper limb exoskeleton has been implemented within the simulating software OpenSim via the platform Notepad++ using xml language. This framework has been used to simulate and analyse the effects at muscular level when the exoskeleton is coupled with the model of the upper limb of the human body for a desired elbow flexion and extension movements.
Then the results i.e. force generated by muscles with and without exoskeleton contribution are plotted and compared. The results of the simulations show that, wearing the exoskeleton, the forces exerted by the muscles decrease significantly.
This thesis is only the starting point of a wide range of possible future works. Aiming at the use of exact controller, optimization technique, cost estimation possibilities applying to real word model and reaching the people in need.
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SIQUEIRA, Patrícia Barros Lima de. „OpenGMP: requisitos de um sistema de informação para gestão de múltiplos projetos“. Universidade Federal de Pernambuco, 2009. https://repositorio.ufpe.br/handle/123456789/2354.
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Previous issue date: 2009O ambiente de múltiplos projetos é uma realidade para as organizações que querem exercer suas atividades no mundo atual, o qual determina que múltiplos projetos sejam executados de forma mais rápida, com menor custo e com maior qualidade. A concorrência cada vez mais acirrada exige diferenciais no gerenciamento de projetos. É inserido neste contexto que surge a necessidade do desenvolvimento de ferramentas de gerenciamento de múltiplos projetos cada vez mais capazes de gerenciar os projetos dessas organizações de forma completa e simples. Este trabalho tem por objetivo melhorar os requisitos e funcionalidades da ferramenta de múltiplos projetos GMP (Gerenciador de Múltiplos Projetos), desenvolvida no CIn Centro de Informática da Universidade Federal de Pernambuco, relativas a escopo, tempo, custo e comunicação. Através de um estudo teórico sobre o gerenciamento de projetos e múltiplos projetos, tendo, respectivamente, como base o Project Management Body of Knowledge (PMBOK Terceira Edição) e algumas ferramentas de múltiplos projetos utilizadas no momento, melhoramos e acrescentamos requisitos e funcionalidades ao GMP. Esta nova versão do GMP, chamada de Open GMP, ratifica a proposta da primeira versão e tem como principais qualidades o fato de continuar sendo desenvolvida em uma plataforma livre e web, para garantir o acesso dos dados de qualquer lugar e em tempo real
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Oliveira, Simão Pedro Resende de. „Using 3D virtual worlds in new educational contexts: IT College in OpenSim“. Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/1220.
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Mestrado em Comunicação MultimédiaAs instituições europeias de Ensino Superior, bem como cada agente envolvido nos processos formais de aprendizagem do Ensino Superior, estão actualmente a experimentar profundas mudanças sob as directivas do Processo de Bolonha. Ao mesmo tempo, as instituições recebem uma nova geração de estudantes, com fortes competências tecnológicas, sendo necessário a estas a compreensão de quais as ferramentas a integrar no currículo educacional, de forma a corresponder às necessidades e expectativas dos seus estudantes. Esta reforma educativa toma lugar enquanto a World Wide Web evolui para a “Web 2.0”: um conjunto de ferramentas tecnológicas e serviços impregnados de princípios como a colaboração, a faceta social e a centralização no utilizador. E novas tendências na Web começam a aparecer, através de paradigmas como os Mundos Virtuais 3D. Esta investigação procura primeiramente compreender como desenhar e construir espaços e ferramentas dentro do Mundo Virtual 3D OpenSim que sejam adequadas às novas realidades educativas e sociais; e adicionalmente, procura que este conhecimento seja usado na criação de uma presença no OpenSim para o Eesti Infotehnoloogia Kolledž, uma instituição de Ensino Superior estoniana. As características do IT Kolledž serão obviamente consideradas durante o processo de investigação. ABSTRACT: European Higher Education institutions, as well as every individual involved in higher education formal learning processes, are currently undergoing profound changes under the guidelines of the Bologna Process. Simultaneously, institutions face a new wave of technological-savvy students and are demanded to understand which tools to integrate in educational curricula in order to adapt to their expectations and needs. This whole educational reform takes place while the World Wide Web evolves into "Web 2.0": a set of technological tools and services impregnated with collaborative, social and user-centered attitudes. And new Web tendencies start to unfold, comprising paradigms such as Virtual 3D Worlds. This research aims firstly to understand how to design and build spaces and tools inside 3D virtual world OpenSim that will be adequate in new educational and social realities; and secondly, to use this knowledge to create an OpenSim presence for Eesti Infotehnoloogia Kolledž, an Estonian higher education institution. IT Kolledž's characteristics will be obviously considered during the research process.
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Broquedis, François. „De l'exécution structurée d'applications scientifiques OpenMP sur les architectures hiérarchiques“. Phd thesis, Université Sciences et Technologies - Bordeaux I, 2010. http://tel.archives-ouvertes.fr/tel-00793472.
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Le domaine applicatif de la simulation numérique requiert toujours plus de puissance de calcul. La technologie multicœur aide à satisfaire ces besoins mais impose toutefois de nouvelles contraintes aux programmeurs d'applications scientifiques qu'ils devront respecter s'ils souhaitent en tirer la quintessence. En particulier, il devient plus que jamais nécessaire de structurer le parallélisme des applications pour s'adapter au relief imposé par la hiérarchie mémoire des architectures multicœurs. Les approches existantes pour les programmer ne tiennent pas compte de cette caractéristique, et le respect de la structure du parallélisme reste à la charge du programmeur. Il reste de ce fait très difficile de développer une application qui soit à la fois performante et portable.La contribution de cette thèse s'articule en trois axes. Il s'agit dans un premier temps de s'appuyer sur le langage OpenMP pour générer du parallélisme structuré, et de permettre au programmeur de transmettre cette structure au support exécutif ForestGOMP. L'exécution structurée de ces flots de calcul est ensuite laissée aux ordonnanceurs Cacheet Memory développés au cours de cette thèse, permettant respectivement de maximiser la réutilisation des caches partagés et de maximiser la bande passante mémoire accessible par les programmes OpenMP. Enfin, nous avons étudié la composition de ces ordonnanceurs, et plus généralement de bibliothèques parallèles, en considérant cette voie comme une piste sérieuse pour exploiter efficacement les multiples unités de calcul des architectures multicœurs.Les gains obtenus sur des applications scientifiques montrent l'intérêt d'une communication forte entre l'application et le support exécutif, permettant l'ordonnancement dynamique et portable de parallélisme structuré sur les architectures hiérarchiques.
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Durán, González Alejandro. „Self-tuned parallel runtimes: a case of study for OpenMP“. Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6026.
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In recent years parallel computing has become ubiquitous. Lead by the spread of commodity multicore processors, parallel programming is not anymore an obscure discipline only mastered by a few.Unfortunately, the amount of able parallel programmers has not increased at the same speed because is not easy to write parallel codes.Parallel programming is inherently different from sequential programming. Programmers must deal with a whole new set of problems: identification of parallelism, work and data distribution, load balancing, synchronization and communication.Parallel programmers have embraced several languages designed to allow the creation of parallel applications. In these languages, the programmer is not only responsible of identifying the parallelism but also of specifying low-level details of how the parallelism needs to exploited (e.g. scheduling, thread distribution ...). This is a burden than hampers the productivity of the programmers.We demonstrate that is possible for the runtime component of a parallel environment to adapt itself to the application and the execution environment and thus reducing the burden put into the programmer. For this purpose we study three different parameters that are involved in the parallel exploitation of the OpenMP parallel language: parallel loop scheduling, thread allocation in multiple levels of parallelism and task granularity control.In all the cases, we propose a self-tuned algorithm that will first perform an on-line profiling of the application and based on the information gathered it will adapt the value of the parameter to the one that maximizes the performance of the application.Our goal is not to develop methods that outperform a hand-tuned application for a specific scenario, as this is probably just as difficult as compiler code outperforming hand-tuned assembly code, but methods that get close to that performance with a minimum effort from the programmer. In other words, what we want to achieve with our self-tuned algorithms is to maximize the ratio performance over effort so the entry level to the parallelism is lower. The evaluation of our algorithms with different applications shows that we achieve that goal.