17 research outputs found

    Software caching techniques and hardware optimizations for on-chip local memories

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    Despite the fact that the most viable L1 memories in processors are caches, on-chip local memories have been a great topic of consideration lately. Local memories are an interesting design option due to their many benefits: less area occupancy, reduced energy consumption and fast and constant access time. These benefits are especially interesting for the design of modern multicore processors since power and latency are important assets in computer architecture today. Also, local memories do not generate coherency traffic which is important for the scalability of the multicore systems. Unfortunately, local memories have not been well accepted in modern processors yet, mainly due to their poor programmability. Systems with on-chip local memories do not have hardware support for transparent data transfers between local and global memories, and thus ease of programming is one of the main impediments for the broad acceptance of those systems. This thesis addresses software and hardware optimizations regarding the programmability, and the usage of the on-chip local memories in the context of both single-core and multicore systems. Software optimizations are related to the software caching techniques. Software cache is a robust approach to provide the user with a transparent view of the memory architecture; but this software approach can suffer from poor performance. In this thesis, we start optimizing traditional software cache by proposing a hierarchical, hybrid software-cache architecture. Afterwards, we develop few optimizations in order to speedup our hybrid software cache as much as possible. As the result of the software optimizations we obtain that our hybrid software cache performs from 4 to 10 times faster than traditional software cache on a set of NAS parallel benchmarks. We do not stop with software caching. We cover some other aspects of the architectures with on-chip local memories, such as the quality of the generated code and its correspondence with the quality of the buffer management in local memories, in order to improve performance of these architectures. Therefore, we run our research till we reach the limit in software and start proposing optimizations on the hardware level. Two hardware proposals are presented in this thesis. One is about relaxing alignment constraints imposed in the architectures with on-chip local memories and the other proposal is about accelerating the management of local memories by providing hardware support for the majority of actions performed in our software cache.Malgrat les memòries cau encara son el component basic pel disseny del subsistema de memòria, les memòries locals han esdevingut una alternativa degut a les seves característiques pel que fa a l’ocupació d’àrea, el seu consum energètic i el seu rendiment amb un temps d’accés ràpid i constant. Aquestes característiques son d’especial interès quan les properes arquitectures multi-nucli estan limitades pel consum de potencia i la latència del subsistema de memòria.Les memòries locals pateixen de limitacions respecte la complexitat en la seva programació, fet que dificulta la seva introducció en arquitectures multi-nucli, tot i els avantatges esmentats anteriorment. Aquesta tesi presenta un seguit de solucions basades en programari i maquinari específicament dissenyat per resoldre aquestes limitacions.Les optimitzacions del programari estan basades amb tècniques d'emmagatzematge de memòria cau suportades per llibreries especifiques. La memòria cau per programari és un sòlid mètode per proporcionar a l'usuari una visió transparent de l'arquitectura, però aquest enfocament pot patir d'un rendiment deficient. En aquesta tesi, es proposa una estructura jeràrquica i híbrida. Posteriorment, desenvolupem optimitzacions per tal d'accelerar l’execució del programari que suporta el disseny de la memòria cau. Com a resultat de les optimitzacions realitzades, obtenim que el nostre disseny híbrid es comporta de 4 a 10 vegades més ràpid que una implementació tradicional de memòria cau sobre un conjunt d’aplicacions de referencia, com son els “NAS parallel benchmarks”.El treball de tesi inclou altres aspectes de les arquitectures amb memòries locals, com ara la qualitat del codi generat i la seva correspondència amb la qualitat de la gestió de memòria intermèdia en les memòries locals, per tal de millorar el rendiment d'aquestes arquitectures. La tesi desenvolupa propostes basades estrictament en el disseny de nou maquinari per tal de millorar el rendiment de les memòries locals quan ja no es possible realitzar mes optimitzacions en el programari. En particular, la tesi presenta dues propostes de maquinari: una relaxa les restriccions imposades per les memòries locals respecte l’alineament de dades, l’altra introdueix maquinari específic per accelerar les operacions mes usuals sobre les memòries locals

    Dynamic Analysis of Rockets Launcher

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    This paper deals with dynamic analysis of rockets launcher on a moving vehicle. Mechanical model of a launch rail system with a rocket is represented as a set of solid bodies and deformable elements with a damped elastic support. These launch rail systems enable to fire rockets of different weights and geometric configurations. Unlike them, today´s multiple rocket launcher systems are located in containers. Movement of this type of mechanical system is described with three defined coordinates: movement of a rocket on a deformable ramp, curvature of the top of a deformable ramp and an angle of rotation of the ramp around its longitudinal axis. Mathematical model of the whole system, including rockets launcher and vehicle, represents a system of five nonlinear, nonhomogeneous differential equations of second order. This system is transformed to a system of 10 differential equations of the first order, suitable for numerical solving through the software package MATLAB. Rocket launcher designers can find the obtained simulation and experimental results, represented in a graphical form which is very useful during the development of a new and modification of existing constructions

    The state of SQL-on-Hadoop in the cloud

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    Managed Hadoop in the cloud, especially SQL-on-Hadoop, has been gaining attention recently. On Platform-as-a-Service (PaaS), analytical services like Hive and Spark come preconfigured for general-purpose and ready to use. Thus, giving companies a quick entry and on-demand deployment of ready SQL-like solutions for their big data needs. This study evaluates cloud services from an end-user perspective, comparing providers including: Microsoft Azure, Amazon Web Services, Google Cloud, and Rackspace. The study focuses on performance, readiness, scalability, and cost-effectiveness of the different solutions at entry/test level clusters sizes. Results are based on over 15,000 Hive queries derived from the industry standard TPC-H benchmark. The study is framed within the ALOJA research project, which features an open source benchmarking and analysis platform that has been recently extended to support SQL-on-Hadoop engines. The ALOJA Project aims to lower the total cost of ownership (TCO) of big data deployments and study their performance characteristics for optimization. The study benchmarks cloud providers across a diverse range instance types, and uses input data scales from 1GB to 1TB, in order to survey the popular entry-level PaaS SQL-on-Hadoop solutions, thereby establishing a common results-base upon which subsequent research can be carried out by the project. Initial results already show the main performance trends to both hardware and software configuration, pricing, similarities and architectural differences of the evaluated PaaS solutions. Whereas some providers focus on decoupling storage and computing resources while offering network-based elastic storage, others choose to keep the local processing model from Hadoop for high performance, but reducing flexibility. Results also show the importance of application-level tuning and how keeping up-to-date hardware and software stacks can influence performance even more than replicating the on-premises model in the cloud.This work is partially supported by the Microsoft Azure for Research program, the European Research Council (ERC) under the EUs Horizon 2020 programme (GA 639595), the Spanish Ministry of Education (TIN2015-65316-P), and the Generalitat de Catalunya (2014-SGR-1051).Peer ReviewedPostprint (author's final draft

    A Novel Approach of Determining the Risks for the Development of Hyperinsulinemia in the Children and Adolescent Population Using Radial Basis Function and Support Vector Machine Learning Algorithm

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    Hyperinsulinemia is a condition with extremely high levels of insulin in the blood. Various factors can lead to hyperinsulinemia in children and adolescents. Puberty is a period of significant change in children and adolescents. They do not have to have explicit symptoms for prediabetes, and certain health indicators may indicate a risk of developing this problem. The scientific study is designed as a cross-sectional study. In total, 674 children and adolescents of school age from 12 to 17 years old participated in the research. They received a recommendation from a pediatrician to do an OGTT (Oral Glucose Tolerance test) with insulinemia at a regular systematic examination. In addition to factor analysis, the study of the influence of individual factors was tested using RBF (Radial Basis Function) and SVM (Support Vector Machine) algorithm. The obtained results indicated statistically significant differences in the values of the monitored variables between the experimental and control groups. The obtained results showed that the number of adolescents at risk is increasing, and, in the presented research, it was 17.4%. Factor analysis and verification of the SVM algorithm changed the percentage of each risk factor. In addition, unlike previous research, three groups of children and adolescents at low, medium, and high risk were identified. The degree of risk can be of great diagnostic value for adopting corrective measures to prevent this problem and developing potential complications, primarily type 2 diabetes mellitus, cardiovascular disease, and other mass non-communicable diseases. The SVM algorithm is expected to determine the most accurate and reliable influence of risk factors. Using factor analysis and verification using the SVM algorithm, they significantly indicate an accurate, precise, and timely identification of children and adolescents at risk of hyperinsulinemia, which is of great importance for improving their health potential, and the health of society as a whole

    Impact assessment of concentrate recirculation on the landfill gas production

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    Automatic Prefetch and Modulo Scheduling Transformations for the Cell BE Architecture

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    A Novel Approach of Determining the Risks for the Development of Hyperinsulinemia in the Children and Adolescent Population Using Radial Basis Function and Support Vector Machine Learning Algorithm

    No full text
    Hyperinsulinemia is a condition with extremely high levels of insulin in the blood. Various factors can lead to hyperinsulinemia in children and adolescents. Puberty is a period of significant change in children and adolescents. They do not have to have explicit symptoms for prediabetes, and certain health indicators may indicate a risk of developing this problem. The scientific study is designed as a cross-sectional study. In total, 674 children and adolescents of school age from 12 to 17 years old participated in the research. They received a recommendation from a pediatrician to do an OGTT (Oral Glucose Tolerance test) with insulinemia at a regular systematic examination. In addition to factor analysis, the study of the influence of individual factors was tested using RBF (Radial Basis Function) and SVM (Support Vector Machine) algorithm. The obtained results indicated statistically significant differences in the values of the monitored variables between the experimental and control groups. The obtained results showed that the number of adolescents at risk is increasing, and, in the presented research, it was 17.4%. Factor analysis and verification of the SVM algorithm changed the percentage of each risk factor. In addition, unlike previous research, three groups of children and adolescents at low, medium, and high risk were identified. The degree of risk can be of great diagnostic value for adopting corrective measures to prevent this problem and developing potential complications, primarily type 2 diabetes mellitus, cardiovascular disease, and other mass non-communicable diseases. The SVM algorithm is expected to determine the most accurate and reliable influence of risk factors. Using factor analysis and verification using the SVM algorithm, they significantly indicate an accurate, precise, and timely identification of children and adolescents at risk of hyperinsulinemia, which is of great importance for improving their health potential, and the health of society as a whole
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