Desktop Grids are rapidly gaining popularity as a cost-effective computing platform for the execution of applications with extensive computing needs. As opposed to grids and clusters, these systems are characterized b...
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ISBN:
(纸本)9781424437511
Desktop Grids are rapidly gaining popularity as a cost-effective computing platform for the execution of applications with extensive computing needs. As opposed to grids and clusters, these systems are characterized by having a non-dedicated infrastructure. These unique characteristics need to be considered in developing resource management strategies for Desktop Grids. Several frameworks for the performance evaluation of resource management strategies have been suggested for grids. However, similar projects for Desktop Grids are still lacking. This paper presents MGST the first performance testing framework for Desktop Grids. We discuss the design of the tool and show how it can be used to analyze and improve the performance of an existing Desktop Grid scheduling policy.
distributed storage systems have become popular for handling the enormous amounts of data in network-centric systems. A distributed storage system provides client processes with the abstraction of a shared variable th...
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ISBN:
(纸本)9781424437511
distributed storage systems have become popular for handling the enormous amounts of data in network-centric systems. A distributed storage system provides client processes with the abstraction of a shared variable that satisfies some consistency and reliability properties. Typically the properties are ensured through a replication-based implementation. This paper presents an algorithm for a replicated read-write register that cat? tolerate Byzantine failures of some of the replica servers. The targeted consistency condition is a version of regularity that supports multiple writers. Although regularity is weaker than the more frequently supported condition of atomicity it is still strong enough to be useful in some important applications. By weakening the consistency condition, the algorithm can support multiple writers more efficiently than the known multi-writer algorithms for atomic consistency.
Technique advances have made image capture and storage very convenient, which results in an explosion of the amount of visual information. It becomes difficult to find useful information from these tremendous data. Co...
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ISBN:
(纸本)9781424437511
Technique advances have made image capture and storage very convenient, which results in an explosion of the amount of visual information. It becomes difficult to find useful information from these tremendous data. Content-based Visual Information Retrieval (CBVIR) is emerging as one of the best solutions to this problem. Unfortunately, CBVIR is a very compute-intensive task. Nowadays, with the boom of multi-core processors, CBVIR can be accelerated by exploiting multi-core processing capability. In this paper, we propose a parallelization implementation of a CBVIR system facing to server application and use some serial and parallel optimization techniques to improve its performance on an 8-core and on a 16-core systems. Experimental results show that optimized implementation can achieve very fast retrieval on the two multicore systems. We also compare the performance of the application on the two multi-core systems and give an explanation of the performance difference between the two systems. Furthermore, we conduct detailed scalability and memory performance analysis to identify possible bottlenecks in the application. Based on these experimental results and performance analysis, we gain many insights into developing efficient applications on future multicore architectures.
The term resiliency has been used in many fields like child psychology, ecology, business, and several others, with the common meaning of expressing the ability to successfully accommodate unforeseen environmental per...
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ISBN:
(纸本)9781424437511
The term resiliency has been used in many fields like child psychology, ecology, business, and several others, with the common meaning of expressing the ability to successfully accommodate unforeseen environmental perturbations or disturbances. The adjective resilient has been in use for decades in the field of dependable computing systems however essentially as a synonym of fault-tolerant, thus generally ignoring the unexpected aspect of the phenomena the systems may have to face. These phenomena become of primary relevance when moving to systems like the future large, networked, evolving systems constituting complex information infrastructures - perhaps involving everything from super-computers and huge server "farms" to myriads of small mobile computers and tiny embedded devices, with humans being central part of the operation of such systems. Such systems are in fact the dawning of the ubiquitous systems that will support Ambient Intelligence. With such ubiquitous systems, what is at stake is to maintain dependability, i.e., the ability to deliver service that can justifiably be trusted, in spite of continuous changes. Therefore the term resilience and resilient computing can be applied to the design of ubiquitous systems and defined as the search for the following property: the persistence of service delivery that can justifiably be trusted, when facing changes. Changes may be of different nature, with different prospect and different timing. Therefore the design of ubiquitous systems requires the mastering of many, often separated, engineering disciplines that span from advanced probability to logic, from human factors to cryptology and information security and to management of large projects. From an educational point of view, very few, if any, Universities are offering a comprehensive and methodical track that is able to provide students with a sufficient preparation that makes them able to cope with the challenges posed by the design of ubiquitous systems.
Multicore systems have become standard for desktop computers today. Current operating systems and software development tools provide straightforward means to use the additional computing power. However, a more fundame...
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ISBN:
(纸本)9780769535739
Multicore systems have become standard for desktop computers today. Current operating systems and software development tools provide straightforward means to use the additional computing power. However, a more fundamental change in the design and development of software is required to fully exploit the power of multicore systems. Furthermore, the fast growing market of embedded systems is currently largely unaffected by the introduction of multicore systems. This will change quickly in the future, which will mean that there will be a demand on efficient development of reliable embedded software that can give real-time guarantees and exploit the available power on multicore systems. The JEOPARD project addresses this demand by developing Java software tools to exploit multicore power while ensuring correctness and predictable timing. This paper gives an overview of the JEOPARD project and focuses on key technical issues such as real-time scheduling and real-time garbage collection on multi-core systems.
Supplier selection and evaluation are one of the most critical activities of a company in today's competitive business world. Partnering with the suppliers has become a key factor to the success of an organization...
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ISBN:
(纸本)9780769536422
Supplier selection and evaluation are one of the most critical activities of a company in today's competitive business world. Partnering with the suppliers has become a key factor to the success of an organization. The selection of supplier satisfying different evaluation criteria, is therefore of main importance and builds the topic of this paper This selection process is a difficult decision and optimization problem, such as data mining technology. This paper utilizes an integrated approach to find the interesting pattern Of supplier. This research has employed a numerical example for the explanation of the proposed approach, and the results show that the method is effective and applicable for supplier selection. In short, the approach provides a new route to guide the further research concerning supplier research.
Metaschedulers can distribute parts of a Bag-of-Tasks (BoT) application among various resource providers in order to speed up its execution. When providers cannot disclose private information such as their load and co...
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ISBN:
(纸本)9781424437511
Metaschedulers can distribute parts of a Bag-of-Tasks (BoT) application among various resource providers in order to speed up its execution. When providers cannot disclose private information such as their load and computing power, which are usually heterogeneous, the metascheduler needs to make blind scheduling decisions. We propose three policies for composing resource offers to schedule deadline-constrained BoT applications. Offers act as a mechanism in which resource providers expose their interest in executing an entire BoT or only part of it without revealing their load and total computing power We also evaluate the amount of information resource providers need to expose to the metascheduler and its impact on the scheduling. Our main findings are: (i) offer-based scheduling produces less delay for jobs that cannot meet deadlines in comparison to scheduling based on load availability (i.e. free time slots);thus it is possible to keep providers' load private when scheduling multi-site BoTs;and (ii) if providers publish their total computing power they can have more local jobs meeting deadlines.
The software in modern systems has become too complex to make accurate predictions about their performance under different configurations. Real-time or even responsiveness requirements cannot be met because it is not ...
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ISBN:
(纸本)9780769536804
The software in modern systems has become too complex to make accurate predictions about their performance under different configurations. Real-time or even responsiveness requirements cannot be met because it is not possible to perform admission control for new or changing tasks if we cannot tell how their execution affects the other tasks already running. Previously, we proposed a resource-allocation middleware that manages the execution of tasks in a complex distributed system with real-time requirements. The middleware behavior can be modeled depending on the configuration of the tasks running, so that the performance of any given configuration can be calculated. This makes it possible to have admission control in such a system, but the model requires knowledge of run-time parameters. We propose the utilization of machine-learning algorithms to obtain the model parameters, and be able to predict the system performance under any configuration, so that we can provide a full admission control mechanism for complex softwaresystems.
distributed real-time systems play an increasingly vital role in our society. The most important aspect of such systems is the scheduling algorithm, which must guarantee that every job in the system will meet its dead...
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distributed real-time systems play an increasingly vital role in our society. The most important aspect of such systems is the scheduling algorithm, which must guarantee that every job in the system will meet its deadline, providing high-quality (precise) results. In this paper we evaluate by simulation the performance of strategies for the scheduling of parallel jobs (gangs) in a homogeneous distributed real-time system with possible software faults. For each scheduling policy we provide an alternative version which allows imprecise computations. We propose a performance metric applicable to our problem, which takes into account the number of jobs guaranteed, as well as the precision of the results of each guaranteed job. The simulation results show that the alternative versions of the algorithms outperform their respective counterparts. To the best of our knowledge, a real-time gang scheduling approach that utilizes imprecise computations has never been discussed in the literature before.
In this paper, we discuss the procedures how to make Viterbi decoder faster. The implementation in Intel CPU with SSE4 parallel processing instruction sets and some other methods achieves the decoding speed 47.05 Mbps...
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ISBN:
(纸本)9780769537474
In this paper, we discuss the procedures how to make Viterbi decoder faster. The implementation in Intel CPU with SSE4 parallel processing instruction sets and some other methods achieves the decoding speed 47.05 Mbps (0.64 Mbps originally). The DVB-T mode used in Taiwan needs 13.27 Mbps to achieve real-time reception, so our implementation of software Viterbi decoder takes only 28% CPU loading.
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