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Self-healing Techniques for Web-based Applications

Magalhães, João Paulo
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
47.80786%
Web-based applications play an important role for the business of many enterprises. Numbers recently published, in the Internet Retailer Magazine, reveal the vibrancy of these businesses: in 2012 the volume of online sales grew about 19% in Latin America reaching $15.42 billion, grew 16% in US reaching $225.54 billion, grew 16% in Europe reaching $302.20 billion and grew 32% in Asia reaching $256.50 billion. Supporting this growth, there exist applications that are becoming increasingly complex in terms of functionalities and management. Such complexity can lead to scenarios of service unavailability or performance loss, damaging the revenue and the company’s reputation. According to Joshua Bixby, the president of Strangeloop Corporation, “one second of performance loss could cost $2.5 million in sales per year for a site that typically earns $100,000 a day”. Likely, “eight out of 10 visitors who have an unsatisfactory experience with a website are unlikely to return. Of these, three will go on to tell others about their poor impression of the site”. In 2001, Paul Horn from IBM, has referred the systems complexity as the major blocking factor affecting the IT industry sectors. According to him, the complexity of systems tends to be so high that they become difficult to maintain and manage. To tackle this problem he proposed the concept of Autonomic Computing (AC). AC is an holistic vision in which systems have autonomous management capabilities. It defines four self-managing attributes: self-configure...

Uma abordagem de predição da dinâmica comportamental de processos para prover autonomia a ambientes distribuídos; An approach to provide autonomy to distributed environments by predicting the dynamics of process behavior

Dodonov, Evgueni
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/07/2009 Português
Relevância na Pesquisa
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A evolução de sistemas distribuídos resultou em aumento significativo de complexidade para manutenção e gerenciamento, tornando pouco eficientes técnicas convencionais baseadas em intervenções manuais. Isso motivou pesquisas que deram origem ao paradigma de computação autônoma (Autonomic Computing), que provê aspectos de auto-configuração, auto-recuperação, auto-otimização e auto-proteção a fim de tornar sistemas auto-gerenciáveis. Nesse contexto, esta tese teve como objetivo prover autonomia a ambientes distribuídos, sem a necessidade de mudar o paradigma de programação e as aplicações de usuários. Para isso, propôs-se uma abordagem que emprega técnicas para compreensão e predição de dinâmicas comportamentais de processos, utilizando abordagens de sistemas dinâmicos, inteligência artificial e teoria do caos. Os estudos realizados no decorrer desta pesquisa demonstraram que, ao predizer padrões comportamentais, pode-se otimizar diversos aspectos de computação distribuída, suportando tomadas de decisão autônomas pelos ambientes. Para validar a abordagem proposta, foi desenvolvida uma política de escalonamento distribuído, denominada PredRoute, a qual utiliza o conhecimento sobre o comportamento de processos para otimizar...

Uma arquitetura baseada em políticas para o provimento de QoS utilizando princípios de Autonomic Computing; A policy-based architecture for QoS provisioning using autonomic computing principles

Franco, Theo Ferreira
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
68.21587%
Sistemas corporativos modernos cada vez mais dependentes da rede e a integração de serviços entorno do modelo TCP/IP elevam a exigência de Qualidade de Serviço da infraestrutura de TI. Neste cenário, o dinamismo das redes atuais em conjunto com os novos requisitos de QoS exigem que a infra-estrutura de TI seja mais autônoma e confiável. Para tratar esta questão, o modelo de Gerenciamento de Redes Baseado em Políticas, proposto pelo IETF, vem se consolidando como uma abordagem para controlar o comportamento da rede através do controle das configurações dos seus dispositivos. Porém, o foco deste modelo é o gerenciamento de políticas internas a um domínio administrativo. Esta característica faz com que o modelo possua algumas limitações, tais como a incapacidade de estabelecer qualquer tipo de coordenação entre diferentes PDPs e a impossibilidade de reagir a eventos externos. Visando agregar autonomia ao modelo de gerenciamento baseado em políticas, este trabalho propõe uma arquitetura em camadas que empregue os conceitos de Autonomic Computing relacionados a: i) adaptação dinâmica dos recursos gerenciados em resposta às mudanças no ambiente, ii) integração com sistemas de gerenciamento de outros domínios através do recebimento de notificações destes...

Manutenção da consistência do estado dos dados de gerenciamento em sistemas de gerenciamento autonômico baseados em infraestruturas peer-to-peer

Nobre, Jéferson Campos
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
47.778613%
O Gerenciamento Autonômico de Redes é uma visão que utiliza princípios da Computação Autonômica para o Gerenciamento de Redes. Além disso, algum grau de descentralização é necessário para habilitar capacidades autonômicas completas. Uma alternativa interessante de infraestrutura para essa união é a utilização de overlays Peer-to-Peer (P2P). No entanto, a consistência do estado dos dados de gerenciamento entre os peers é um desafio importante. Mecanismos tradicionais para manter a consistência desses estados são implementados por meio de centralização, o que desperdiça algumas propriedades desejáveis de abordagens P2P. Em contraste com esses mecanismos, é proposto um mecanismo distribuído, escalável e robusto para a manutenção da consistência do estado dos dados de gerenciamento pela introdução de funcionalidades de Manutenção da Verdade Multiagente. Além disso, são propostas estratégias de comunicação para prover suporte a essas funcionalidades. São apresentados também estudos de caso para ilustrar as possibilidades da proposta: o gerenciamento cooperativo de falhas em enlaces Ethernet em provedores de serviços e a ativação distribuída de políticas de gerenciamento de redes. Experimentos simulados são realizados a fim de verificar as propriedades de escalabilidade e robustez da presente proposta.; Autonomic network management is a vision that brings Autonomic Computing principles to Network Management. Besides...

Model checking for autonomic systems specified with ASSL

Vassev, Emil; Hinchey, Mike; Quigley, Aaron
Fonte: University of Limerick Publicador: University of Limerick
Tipo: Conference item; all_ul_research; ul_published_reviewed; none
Português
Relevância na Pesquisa
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non-peer-reviewed; Autonomic computing augurs great promise for deep space exploration missions, bringing onboard intelligence and less reliance on control links. As part of our research on the ASSL (Autonomic System Specification Language) framework, we have successfully specified autonomic properties, verified their consistency, and generated prototype models for both the NASA ANTS (Autonomous Nano-Technology Swarm) concept mission and the NASA Voyager mission. The first release of ASSL provides built-in consistency checking and functional testing as the only means of software verification. We discuss our work on model checking autonomic systems specified with ASSL. In our approach, an ASSL specification is translated into a state-transition model, over which model checking is performed to verify whether the ASSL specification satisfies correctness properties. The latter are expressed as temporal logic formulae expressed over sets of ASSL constructs. We also discuss possible solutions to the state-explosion problem in terms of state graph abstraction and probability weights assigned to states. Moreover, we present an example case study involving checking liveness properties of autonomic systems with ASSL

Towards model checking with Java PathFinder for autonomic systems specified and generated with ASSL.

Vassev, Emil; Hinchey, Mike; Quigley, Aaron
Fonte: University of Limerick Publicador: University of Limerick
Tipo: Conference item; all_ul_research; ul_published_reviewed; none
Português
Relevância na Pesquisa
57.86164%
non-peer-reviewed; Autonomic computing has been recognized as a valid approach to the development of large-scale self-managing complex systems. The Autonomic System Specification Language (ASSL) is an initiative for the development of autonomic systems where we approach the problem of formal specification, validation, and code generation of such systems within a framework. As part of our research on ASSL, we have developed and investigated different approaches to software verification. Currently, the latter is possible via built-in consistency checking and functional testing where handling logical errors is a daunting task. In this paper, we discuss our work on model checking with NASA’s Java PathFinder tool, which is an explicit-state model checker that works directly on the generated Java code. We propose optional automatic generation of test drivers in the form of PathFinder API calls seeded in the ASSL-generated code.

Developing model-checking mechanisms for ASSL: an experience report

Vassev, Emil; Hinchey, Mike
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: info:eu-repo/semantics/conferenceObject; all_ul_research; ul_published_reviewed
Português
Relevância na Pesquisa
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peer-reviewed; The Autonomic System Specification Language (ASSL) is a formal method dedicated to autonomic computing, and as such, assists developers with formal specification, validation and code generation of autonomic systems. Due to the synthesis approach of automatic code generation, ASSL guarantees consistency between a specification and the corresponding implementation. Moreover, one of the major objectives of the framework is to assure the correctness of autonomic systems via the inclusion of tools targeting model checking. In this paper, we report our experience in developing model-checking mechanisms for ASSL.

On Autonomic HPC Clouds

Petcu, Dana
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/publishedVersion; info:eu-repo/semantics/bookPart; info:eu-repo/semantics/conferenceObject
Publicado em /10/2015 Português
Relevância na Pesquisa
47.921606%
The long tail of science using HPC facilities is looking nowadays to instant available HPC Clouds as a viable alternative to the long waiting queues of supercomputing centers. While the name of HPC Cloud is suggesting a Cloud service, the current HPC-as-a-Service is mainly an offer of bar metal, better named cluster-on-demand. The elasticity and virtualization benefits of the Clouds are not exploited by HPC-as-a-Service. In this paper we discuss how the HPC Cloud offer can be improved from a particular point of view, of automation. After a reminder of the characteristics of the Autonomic Cloud, we project the requirements and expectations to what we name Autonomic HPC Clouds. Finally, we point towards the expected results of the latest research and development activities related to the topics that were identified.; The work related to Autonomic HPC Clouds is supported by the European Commission under grant agreement H2020-6643946 (CloudLightning). The CLoudLightning project proposal was prepared by eight partner institutions, three of them as earlier partners in the COST Action IC1305 NESUS, benefiting from its inputs for the proposal. The section related to Autonomic Clouds is supported by the Romanian UEFISCDI under grant agreement PN-II-ID-PCE-2011- 3-0260 (AMICAS).; Proceedings of: Second International Workshop on Sustainable Ultrascale Computing Systems (NESUS 2015). Krakow (Poland)...

Fulfilling the vision of automatic computing

Dobson, Simon; Sterritt, Roy; Nixon, Paddy; Hinchey, Mike
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: Article; all_ul_research; ul_published_reviewed; none
Português
Relevância na Pesquisa
57.60869%
peer-reviewed; Efforts since 2001 to design self-managing systems have yielded many impressive achievements, yet the original vision of autonomic computing remains unfulfilled. Researchers must develop a comprehensive systems engineering approach to create effective solutions for next-generation enterprise and sensor systems.

Developing autonomic properties for distributed pattern-recognition systems with ASSL

Vassev, Emil; Mokhov, Serguei A.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Conference item; all_ul_research; ul_published_reviewed; none; none
Português
Relevância na Pesquisa
47.67712%
non-peer-reviewed; In this paper, we discuss our research towards developing special properties that introduce autonomic behavior in pattern-recognition systems. In our approach we use ASSL (Autonomic System Speci cation Language) to formally develop such properties for DMARF (Distributed Modular Audio Recognition Framework). These properties enhance DMARF with an autonomic middleware that manages the four stages of the framework's pattern-recognition pipeline. DMARF is a biologically inspired system employing pattern recognition, signal processing, and natural language processing helping us process audio, textual, or imagery data needed by a variety of scientific applications, e.g., biometric applications. In that context, the notion go autonomic DMARF (ADMARF) can be employed by autonomous and robotic systems that theoretically re- quire less-to-none human intervention other than data collection for pattern analysis and observing the results. In this article, we explain the ASSL speci cation models for the autonomic properties of DMARF.

A SENSOR-BASED APPROACH TO MONITORING WEB SERVICE

Li, JUN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 614460 bytes; application/pdf
Português
Relevância na Pesquisa
47.80786%
As the use of Web expands, Web Service is gradually becoming the basic system infrastructure. However, as it matures and a large number of Web Service becomes available, the focus will shift from service development to service management. One key component in management systems is monitoring. The growing complexity of Web Service platforms and their dynamically varying workloads make manually monitoring them a demanding task. Therefore monitoring tools are required to support the management efforts. Our approach, Web Service Monitoring System (WSMS), utilizes Autonomic Computing technology to monitor Web Service for an automated manager. WSMS correlates lower level events into a meaningful diagnosed symptom which provides higher level information for problem determination. It also gains the ability to take autonomic actions and solve the original problem using corrective actions. In this thesis, a complete design of WSMS is presented along with a practical implementation showing viability and proof of concept of WSMS.; Thesis (Master, Computing) -- Queen's University, 2008-11-12 16:20:13.738

Recovering software tuning parameters

Brake, Nevon
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1394777 bytes; application/pdf
Português
Relevância na Pesquisa
47.80786%
Autonomic Computing is an approach to designing systems that are capable of self-management. Fundamental to the autonomic ideal is a software's awareness of and ability to tune parameters that affect metrics like performance and security. Traditionally, these parameters are tuned by human experts with extensive knowledge of parameter names and effects---existing software was not designed to be self-tuning. Efforts to automate the isolation and tuning of parameters have yielded encouraging results. However, the parameters are identified manually. This thesis proposes the adaptation of reverse engineering techniques for automating the recovery of software tuning parameters. Tuning parameters from several industrially relevant applications are studied for patterns of use. These patterns are used to classify the parameters into a taxonomy, and to develop a metamodel of the source code elements and relationships needed to express them. An extractor is then built to obtain instances of the relationships from source code. The relationships are represented as graphs, which are manipulated and queried for instances of tuning parameter patterns. The recovery is implemented as a tool for finding tuning parameters in applications. Experimental results show that the approach is effective at recovering documented tuning parameters...

AUTONOMIC WORKLOAD MANAGEMENT FOR DATABASE MANAGEMENT SYSTEMS

Zhang, Mingyi
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
57.930425%
In today’s database server environments, multiple types of workloads, such as on-line transaction processing, business intelligence and administrative utilities, can be present in a system simultaneously. Workloads may have different levels of business importance and distinct performance objectives. When the workloads execute concurrently on a database server, interference may occur and result in the workloads failing to meet the performance objectives and the database server suffering severe performance degradation. To evaluate and classify the existing workload management systems and techniques, we develop a taxonomy of workload management techniques. The taxonomy categorizes workload management techniques into multiple classes and illustrates a workload management process. We propose a general framework for autonomic workload management for database management systems (DBMSs) to dynamically monitor and control the flow of the workloads and help DBMSs achieve the performance objectives without human intervention. Our framework consists of multiple workload management techniques and performance monitor functions, and implements the monitor–analyze–plan–execute loop suggested in autonomic computing principles. When a performance issue arises...

Autonomic computing for scheduling in manufacturing systems

Madureira, Ana Maria; Pereira, Ivo; Sousa, Nelson; Ávila, Paulo; Bastos, João
Fonte: Instituto Politécnico do Porto Publicador: Instituto Politécnico do Porto
Tipo: Conferência ou Objeto de Conferência
Publicado em //2009 Português
Relevância na Pesquisa
48.170166%
We describe a novel approach to scheduling resolution by combining Autonomic Computing (AC), Multi-Agent Systems (MAS) and Nature Inspired Optimization Techniques (NIT). Autonomic Computing has emerged as paradigm aiming at embedding applications with a management structure similar to a central nervous system. A natural Autonomic Computing evolution in relation to Current Computing is to provide systems with Self-Managing ability with a minimum human interference. In this paper we envisage the use of Multi-Agent Systems paradigm for supporting dynamic and distributed scheduling in Manufacturing Systems with Autonomic properties, in order to reduce the complexity of managing systems and human interference. Additionally, we consider the resolution of realistic problems. The scheduling of a Cutting and Treatment Stainless Steel Sheet Line will be evaluated. Results show that proposed approach has advantages when compared with other scheduling systems.

Regulating Response Time in an Autonomic Computing System: A Comparision of Proportional Control and Fuzzy Control Approaches

Venkatarama, Harish Sheeranalli; Sekaran, Kandasamy Chandra
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/11/2010 Português
Relevância na Pesquisa
47.80786%
Ecommerce is an area where an Autonomic Computing system could be very effectively deployed. Ecommerce has created demand for high quality information technology services and businesses are seeking quality of service guarantees from their service providers. These guarantees are expressed as part of service level agreements. Properly adjusting tuning parameters for enforcement of the service level agreement is time-consuming and skills-intensive. Moreover, in case of changes to the workload, the setting of the parameters may no longer be optimum. In an ecommerce system, where the workload changes frequently, there is a need to update the parameters at regular intervals. This paper describes two approaches, one, using a proportional controller and two, using a fuzzy controller, to automate the tuning of MaxClients parameter of Apache web server based on the required response time and the current workload. This is an illustration of the self-optimizing characteristic of an autonomic computing system.; Comment: 9 pages, 7 figures, 1 table

Developing Autonomic Properties for Distributed Pattern-Recognition Systems with ASSL: A Distributed MARF Case Study

Vassev, Emil; Mokhov, Serguei A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/12/2011 Português
Relevância na Pesquisa
48.154243%
In this paper, we discuss our research towards developing special properties that introduce autonomic behavior in pattern-recognition systems. In our approach we use ASSL (Autonomic System Specification Language) to formally develop such properties for DMARF (Distributed Modular Audio Recognition Framework). These properties enhance DMARF with an autonomic middleware that manages the four stages of the framework's pattern-recognition pipeline. DMARF is a biologically inspired system employing pattern recognition, signal processing, and natural language processing helping us process audio, textual, or imagery data needed by a variety of scientific applications, e.g., biometric applications. In that context, the notion go autonomic DMARF (ADMARF) can be employed by autonomous and robotic systems that theoretically require less-to-none human intervention other than data collection for pattern analysis and observing the results. In this article, we explain the ASSL specification models for the autonomic properties of DMARF.; Comment: 28 pages; 16 figures; Submitted and accepted in 2010; to appear in "E. Vassev and S. A. Mokhov. Development and evaluation of autonomic properties for pattern-recognition systems with ASSL -- a distributed MARF case study. Transactions on Computational Science...

On the existence of truly autonomic computing systems and the link with quantum computing

Srinivasan, Radhakrishnan; Raghunandan, H. P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
48.02385%
A theoretical model of truly autonomic computing systems (ACS), with infinitely many constraints, is proposed. An argument similar to Turing's for the unsolvability of the halting problem, which is permitted in classical logic, shows that such systems cannot exist. Turing's argument fails in the recently proposed non-Aristotelian finitary logic (NAFL), which permits the existence of ACS. NAFL also justifies quantum superposition and entanglement, which are essential ingredients of quantum algorithms, and resolves the Einstein-Podolsky-Rosen (EPR) paradox in favour of quantum mechanics and non-locality. NAFL requires that the autonomic manager (AM) must be conceptually and architecturally distinct from the managed element, in order for the ACS to exist as a non-self-referential entity. Such a scenario is possible if the AM uses quantum algorithms and is protected from all problems by (unbreakable) quantum encryption, while the managed element remains classical. NAFL supports such a link between autonomic and quantum computing, with the AM existing as a metamathematical entity. NAFL also allows quantum algorithms to access truly random elements and thereby supports non-standard models of quantum (hyper-) computation that permit infinite parallelism.; Comment: 13 pages (two-column...

A Framework for Constraint-Based Deployment and Autonomic Management of Distributed Applications (Extended Abstract)

Dearle, Alan; Kirby, Graham; McCarthy, Andrew
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 24/06/2010 Português
Relevância na Pesquisa
47.778613%
We propose a framework for the deployment and subsequent autonomic management of component-based distributed applications. An initial deployment goal is specified using a declarative constraint language, expressing constraints over aspects such as component-host mappings and component interconnection topology. A constraint solver is used to find a configuration that satisfies the goal, and the configuration is deployed automatically. The deployed application is instrumented to allow subsequent autonomic management. If, during execution, the manager detects that the original goal is no longer being met, the satisfy/deploy process can be repeated automatically in order to generate a revised deployment that does meet the goal.; Comment: 1st International Conference on Autonomic Computing (ICAC'04) pp.300-301, IEEE Computer Society, 2004

Load Distribution Composite Design Pattern for Genetic Algorithm-Based Autonomic Computing Systems

Mannava, Vishnuvardhan; Ramesh, T.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/09/2012 Português
Relevância na Pesquisa
58.1674%
Current autonomic computing systems are ad hoc solutions that are designed and implemented from the scratch. When designing software, in most cases two or more patterns are to be composed to solve a bigger problem. A composite design patterns shows a synergy that makes the composition more than just the sum of its parts which leads to ready-made software architectures. As far as we know, there are no studies on composition of design patterns for autonomic computing domain. In this paper we propose pattern-oriented software architecture for self-optimization in autonomic computing system using design patterns composition and multi objective evolutionary algorithms that software designers and/or programmers can exploit to drive their work. Main objective of the system is to reduce the load in the server by distributing the population to clients. We used Case Based Reasoning, Database Access, and Master Slave design patterns. We evaluate the effectiveness of our architecture with and without design patterns compositions. The use of composite design patterns in the architecture and quantitative measurements are presented. A simple UML class diagram is used to describe the architecture.; Comment: International Journal on Soft Computing (IJSC)...

A COMPARISON BETWEEN EXPERT SYSTEMS AND AUTONOMIC COMPUTING PLUS MOBILE AGENT APPROACHES FOR FAULT MANAGEMENT.

GUTIÉRREZ,SERGIO ARMANDO; BRANCH,JOHN WILLIAN
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 Português
Relevância na Pesquisa
67.80786%
In this article, a revision of literature on application of expert systems to fault management is presented. Then, a new approach, based on the autonomic computing paradigm and mobile agents technology is introduced. The main features of this new approach are compared to equivalent ones of expert systems. Benefits of the schema based on mobile agents are presented.