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Hisao Kameda - One of the best experts on this subject based on the ideXlab platform.

  • Numerical studies on a paradox for non-cooperative static load balancing in Distributed Computer Systems
    Computers & Operations Research, 2006
    Co-Authors: S. F. El-zoghdy, Hisao Kameda
    Abstract:

    Numerical examples of a Braess-like paradox in which adding capacity to a Distributed Computer system may degrade the performance of all users in the system under non-cooperative optimization have been reported. Unlike the original Braess paradox, in the models examined, this behavior occurs only in the case of finitely many users and not in the case of infinite number of users and the degree of performance degradation can increase without bound. This study examines numerically some examples around the Braess-like paradox in a Distributed Computer system. In the numerical examples, it is observed that the worst-case degree of the paradox (WCDP) is largest in complete symmetry. The dependence of the WCDP on some system parameters is also examined.

  • NASH EQUILIBRIA IN LOAD BALANCING IN Distributed Computer Systems
    International Game Theory Review, 2002
    Co-Authors: Eitan Altman, Hisao Kameda, Yoshihisa Hosokawa
    Abstract:

    The use of game theoretical techniques has been quite successful in describing routing in networks, both in road traffic applications as well as in telecommunication networks applications. We study in this paper a third area of applications of such games, which is load balancing in Distributed Computer Systems. One of the most important questions that arise in all applications of routing games is the existence and uniqueness of equilibrium. Whereas the existence of Nash equilibrium is known for general models of networks under weak assumptions, uniqueness results are only known for very special applications, i.e., either for very special cost functions or for very special topologies. We establish in this paper the uniqueness of an equilibrium for routing games with topologies that model well Distributed Computer Systems, under quite general assumptions on the costs.

  • Braess-like paradoxes in Distributed Computer Systems
    IEEE Transactions on Automatic Control, 2000
    Co-Authors: Hisao Kameda, Eitan Altman, T. Kozawa, Yoshihisa Hosokawa
    Abstract:

    We consider optimal Distributed decisions in Distributed Computer Systems. We identify a Braess like paradox in which adding capacity to the system may degrade the performance of all users. Unlike the original Braess paradox, we show that this behavior occurs only in the case of finitely many users and not in the case of infinite number of users.

  • optimal load balancing in Distributed Computer Systems
    1997
    Co-Authors: Hisao Kameda, Chong-gun Kim, Yongbing Zhang
    Abstract:

    An important consideration in improving the performance of a Distributed Computer system is the balancing of the load between the host Computers. Load balancing may be either static or dynamic; static balancing strategies are generally based on information about the system's average behavior rather than its actual current state, while dynamic strategies react to the current state when making transfer decisions. Although it is often conjectured that dynamic load balancing outperforms static, careful investigation shows that this view is not always valid. Recent research on the problem of optimal static load balancing is clearly and intuitively presented, with coverage of Distributed Computer system models, problem formulation in load balancing, and effective algorithms for implementing optimization. Providing a thorough understanding of both static and dynamic strategies, this book will be of interest to all researchers and practitioners working to optimize performance in Distributed Computer Systems.

  • anomalous relations among various performance objectives in Distributed Computer Systems 1
    1997
    Co-Authors: Hisao Kameda, Takayuki Kozawa
    Abstract:

    Distributed Computer Systems consist of a set of heterogeneous host Computers (i.e., nodes) connected by a communication network. A job that arrives at a node may either be processed locally or transferred to another node for remote processing, which we call load balancing. One possible performance objective of load balancing in Distributed Computer Systems is to minimize the overall mean response time. We can characterize analytically the static load balancing policy whereby the mean overall response time is minimized, which we call the overall optimal policy. This policy, however, lacks fairness in the sense that, for example, two jobs arriving at the same node but being forwarded to different nodes may not have the same expected response time. To satisfy fairness among jobs we can consider an individually optimal load balancing policy whereby jobs arriving at the same node have the same (minimum) expected response time regardless of the nodes which process them. Furthermore, we can think of a node optimal load balancing policy whereby the mean response time of jobs arriving at each node is minimum given the decision by the other nodes of which jobs arriving at those nodes are forwarded. We report the existence of some seemingly anomalous phenomena in the mutual relation among the above policies.

K.h. Kim - One of the best experts on this subject based on the ideXlab platform.

  • Fair distribution of concerns in design and evaluation of fault-tolerant Distributed Computer Systems
    Computer Communications, 1994
    Co-Authors: K.h. Kim
    Abstract:

    In analysing the fault tolerance capabilities of Distributed Computer system designs, the functionally or physically replaceable components have usually been modelled as one of the two extreme types with respect to their failure symptoms (faulty output behaviour): the fail-silent unit (FSU) model at the simplest end, and the malicious unit (MaU) model, also called the Byzantine unit model, at the other end. The basic weaknesses of these models for use in practical system design and evaluation are pointed out. The FSU model is justifiable for handling most simple parts of a system, but not so for other complex parts. The MaU model is misleading in that it tends to draw attention to events of negligible occurrence probabilities while taking attention away from events of higher occurrence probabilities. It is also pointed out that the state-of-the-art in analytic modelling and evaluation of fault-tolerant Distributed Computer Systems has a vast weakly characterized region in the domain of conceivable component models enclosed by the two extreme models. The main constructive proposition made with respect to advancing the state-of-the-art is to establish scientific procedures for fair distribution of concerns over possible occurrences of anomalous events during system design and validation. A direction for obtaining such a fair modelling procedure relying on extensive probabilistic reasoning is proposed. The principle may have broad applicability, extending much beyond the area of fault-tolerant computing.

  • Implementation of the conversation scheme in message-based Distributed Computer Systems
    IEEE Transactions on Parallel and Distributed Systems, 1992
    Co-Authors: S.-m. Yang, K.h. Kim
    Abstract:

    Several different approaches for implementing conversations in message-based Distributed Computer Systems (DCSs) are discussed. Two different exit control strategies (synchronous and asynchronous) and three different approaches to execution of the conversation acceptance test (centralized, decentralized, and semicentralized) are examined and compared in terms of system performance and implementation cost. An efficient approach to run-time management of recovery information based on an extension of the recovery cache scheme is also discussed. The two major types of conversation structures, name-linked recovery block and abstract data type conversations, are examined to analyze which execution approaches are the most efficient for each conversation structure. As a case study, an unmanned vehicle system is used to illustrate how the approaches can be used in a realistic real-time application. >

  • Designing fault tolerance capabilities into real-time Distributed Computer Systems
    [1988] Proceedings. Workshop on the Future Trends of Distributed Computing Systems in the 1990s, 1
    Co-Authors: K.h. Kim
    Abstract:

    Some of the fault-tolerance schemes that have been established as promising ones for use in real-time Distributed Computer Systems (DCSs) are reviewed. Major issues that remain to be resolved in the 1990s are also discussed. By and large, the design of fault-tolerant real-time DCSs is an immature field. Many of the promising fault tolerance schemes have not been adequately evaluated. It is hoped that many more testbed-based efforts will be made in the field of fault-tolerant real-time Distributed computing. >

Vadym Mukhin - One of the best experts on this subject based on the ideXlab platform.

  • IDAACS - Study of the Functioning of the Distributed Computer System with a Resource Control Mechanism Based on a Network-Centric Approach
    2019 10th IEEE International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACS), 2019
    Co-Authors: Vadym Mukhin, Yaroslav Kornaga, Oksana Herasymenko, Viktor Vyshnivskyi, Yuriy Bazaka, Maxim Bazaliy
    Abstract:

    The task to increase the scalability of the Distributed Computer Systems (DCS) arises the new challenges for developing of the effective resources control mechanisms for such Systems. This issue is particularly significant for the Distributed Computer Systems with a decentralized resource control mechanism. The paper describes a resource reservation mechanism which allow to prevent the total loading of DCS computational resources. This research is devoted to the study of the functioning of the resource control system (RCS) based on a network-centric approach in the context of resource reservations.

  • The scheduler for Distributed Computer Systems based on the network centric approach to resources control
    2017 9th IEEE International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACS), 2017
    Co-Authors: Zhenbing Hu, Vadym Mukhin, Yaroslav Kornaga, Artem Volokyta, Vadym Mukhin, Oksana Herasymenko
    Abstract:

    In this paper is suggested the design of a scheduler for the resources control of the Distributed Computer system based on a network-centric approach. There is considered the Distributed Computer system which is a set of heterogeneous computing nodes, been connected by heterogeneous data transmission channels and these channels are multi-channels by their nature. The scheduler for such Distributed system must take into account the features of the system in order to improve the efficiency of the system operation. The proposed approach to resources control allows increase the throughput of the Distributed Computer system.

  • IDAACS - The scheduler for Distributed Computer Systems based on the network centric approach to resources control
    2017 9th IEEE International Conference on Intelligent Data Acquisition and Advanced Computing Systems: Technology and Applications (IDAACS), 2017
    Co-Authors: Vadym Mukhin, Yaroslav Kornaga, Artem Volokyta, Oksana Herasymenko
    Abstract:

    In this paper is suggested the design of a scheduler for the resources control of the Distributed Computer system based on a network-centric approach. There is considered the Distributed Computer system which is a set of heterogeneous computing nodes, been connected by heterogeneous data transmission channels and these channels are multi-channels by their nature. The scheduler for such Distributed system must take into account the features of the system in order to improve the efficiency of the system operation. The proposed approach to resources control allows increase the throughput of the Distributed Computer system.

  • Stochastic RA-Network for the Nodes Functioning Analysis in the Distributed Computer Systems
    International Journal of Computer Network and Information Security, 2016
    Co-Authors: Vadym Mukhin, Heorhii Loutskii, Yaroslav Kornaga
    Abstract:

    In the paper is described the simulating process for the situations analysis and the decisions making about the functioning of the Distributed Computer Systems (DCS) nodes on the basis of special stochastic RA-networks mechanism. There are presented the main problems in the estimations of the DCS nodes functioning parameters and there are shown that the suggested RA-networks mechanism allows simulate the data flow with the different, including the significantly different intensities, what is particularly important in for the situations analysis and the decisions making in the DCS nodes parameters dynamics control.

  • Adaptive security system based on intelligent agents for Distributed Computer Systems
    2016 International Conference on Development and Application Systems (DAS), 2016
    Co-Authors: Vadym Mukhin, Yaroslav Kornaga, Viktor Steshyn, Yevgeniy Mostovoy
    Abstract:

    In the paper is described a complex adaptive system, which is based on the neural network and on the intelligent agents. This system allows realize an adaptive control for the information security mechanism, it provides timely response to threats and performs the decision making in the real time mode. The developed system allows identify and classify the attacks and to prevent them in order to ensure operation of the fail-safe system and the availability of information resources. The experiments for the data transfer rate analysis in the different observation period on the secured nodes in the Distributed Computer system are performed.

Nam Sung Kim - One of the best experts on this subject based on the ideXlab platform.

  • pd gem5 simulation infrastructure for parallel Distributed Computer Systems
    IEEE Computer Architecture Letters, 2016
    Co-Authors: Mohammad Alian, Daehoon Kim, Nam Sung Kim
    Abstract:

    Improving the performance and power efficiency of a single processor has been fraught with various challenges stemming from the end of the classical technology scaling. Thus, the importance of efficiently running applications on a parallel/Distributed Computer system has continued to increase. In developing and optimizing such a parallel/Distributed Computer system, it is critical to study the impact of the complex interplay amongst processor, node, and network architectures on performance and power efficiency in detail. This necessitates a flexible, detailed and open-source full-system simulation infrastructure. However, our community lacks such an infrastructure. In this paper, we present pd-gem5 , a gem5 -based infrastructure that can model and simulate a parallel/Distributed Computer system using multiple simulation hosts. Our experiment shows that pd-gem5 running on six simulation hosts speeds up the simulation of a 24-node Computer system up to 3.2× compared with running on a single simulation host.

  • pd-gem5 : Simulation Infrastructure for Parallel/Distributed Computer Systems
    IEEE Computer Architecture Letters, 2016
    Co-Authors: Mohammad Alian, Daehoon Kim, Nam Sung Kim
    Abstract:

    Improving the performance and power efficiency of a single processor has been fraught with various challenges stemming from the end of the classical technology scaling. Thus, the importance of efficiently running applications on a parallel/Distributed Computer system has continued to increase. In developing and optimizing such a parallel/Distributed Computer system, it is critical to study the impact of the complex interplay amongst processor, node, and network architectures on performance and power efficiency in detail. This necessitates a flexible, detailed and open-source full-system simulation infrastructure. However, our community lacks such an infrastructure. In this paper, we present pd-gem5 , a gem5 -based infrastructure that can model and simulate a parallel/Distributed Computer system using multiple simulation hosts. Our experiment shows that pd-gem5 running on six simulation hosts speeds up the simulation of a 24-node Computer system up to 3.2× compared with running on a single simulation host.

Chong-gun Kim - One of the best experts on this subject based on the ideXlab platform.

  • optimal load balancing in Distributed Computer Systems
    1997
    Co-Authors: Hisao Kameda, Chong-gun Kim, Yongbing Zhang
    Abstract:

    An important consideration in improving the performance of a Distributed Computer system is the balancing of the load between the host Computers. Load balancing may be either static or dynamic; static balancing strategies are generally based on information about the system's average behavior rather than its actual current state, while dynamic strategies react to the current state when making transfer decisions. Although it is often conjectured that dynamic load balancing outperforms static, careful investigation shows that this view is not always valid. Recent research on the problem of optimal static load balancing is clearly and intuitively presented, with coverage of Distributed Computer system models, problem formulation in load balancing, and effective algorithms for implementing optimization. Providing a thorough understanding of both static and dynamic strategies, this book will be of interest to all researchers and practitioners working to optimize performance in Distributed Computer Systems.

  • An algorithm for optimal static load balancing in Distributed Computer Systems
    IEEE Transactions on Computers, 1992
    Co-Authors: Chong-gun Kim, Hisao Kameda
    Abstract:

    The authors propose a load-balancing algorithm that determines the optimal load for each host so as to minimize the overall mean job response time in a Distributed Computer system that consists of heterogeneous hosts. The algorithm is a simplified and easily understandable version of the single-point algorithm originally presented by A.N. Tantawi and D. Towsley (1985). >

  • FTDCS - Dynamic load balancing in Distributed Computer Systems with star topology
    Proceedings of the Fifth IEEE Computer Society Workshop on Future Trends of Distributed Computing Systems, 1
    Co-Authors: Kyung-soo Lim, Chong-gun Kim
    Abstract:

    We consider sender-initiated dynamic load balancing policies in Distributed Computer system with star topology. In this system, the processing power of central node may be greater than that of peripheral nodes and the job arrival rate of each node may be different. The performance of load balancing may be very different according to the selection of sender criteria and receiver criteria for job transfer. But the optimal decision of sender and receiver criteria is very difficult in heterogeneous Distributed Computer Systems. In this paper we propose effective destination decision policies using dynamic criteria such as mean job response time of node and estimated response time of job instead of fixed threshold for dynamic load balancing. We also show that the proposed policies produce very interesting results in heterogeneous Distributed Computer Systems with star topology.