As an alternative to spatial parallelization of simulation models, time-parallelsimulation offers the potential for massive parallelism with a high level of independence between the parallel processes. Unfortunately,...
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ISBN:
(纸本)0769523838
As an alternative to spatial parallelization of simulation models, time-parallelsimulation offers the potential for massive parallelism with a high level of independence between the parallel processes. Unfortunately, due to inherent problems, the applicability of time-parallelsimulation is restricted. Therefore, it has been proposed recently, to use approximation with time-parallelsimulation in order to facilitate its application and to extend the class of models suitable for time-parallelsimulation. As a proof-of-concept, this work shows how approximate temporal parallelization can be applied to the simulation of road traffic. Traffic simulation is used extensively in transportation research for various purposes, e.g. analysis of traffic phenomena, traffic forecast, and optimization of traffic flow. Depending on the level of fidelity, a traffic model exhibits a state space of moderate to high complexity. This paper is intended to discuss the basic properties of time-parallel traffic simulation and to examine its feasibility. Experiments with a sequential microscopic traffic simulator that emulates important aspects of a corresponding time-parallel simulator suggest this feasibility.
We describe MOSS, a small language of mobile distributed objects and system-wide references, uncommitted to any distributedsimulation protocol, but which can be executed as a distributed conservative simulation with ...
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We describe MOSS, a small language of mobile distributed objects and system-wide references, uncommitted to any distributedsimulation protocol, but which can be executed as a distributed conservative simulation with automatic deduction of lookahead. We show how the MOSS programmer can control the dynamic distribution and locality of simulation objects by simple means which provide natural modelling functions. Preliminary results show how programmed locality can reduce communication costs in simulation.
A study is presented in applying optimistic parallel discrete event simulation techniques using reverse execution to perform instruction-level simulations of distributed memory multi-processor systems. A static progra...
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ISBN:
(纸本)9780769528984
A study is presented in applying optimistic parallel discrete event simulation techniques using reverse execution to perform instruction-level simulations of distributed memory multi-processor systems. A static program analysis approach is described to optimize pre-processed simulated applications in order to remove certain overheads associated with forward event execution and to enable reversible execution. Reverse execution of floating point operations are also considered. Preliminary performance measurements are presented indicating this approach offers promise in speeding up parallel multi-processor simulations.
Running a large-scale distributedsimulation may need a large amount of computing resources at geographically different locations. These resources may be from different organizations. The simulation may run for a long...
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ISBN:
(纸本)0769518532
Running a large-scale distributedsimulation may need a large amount of computing resources at geographically different locations. These resources may be from different organizations. The simulation may run for a long period of time and the availability and the amount of computing resources available may change during the course of the simulation execution. Therefore, coordinating and managing the resources for distributedsimulation to complete the simulation efficiently and effectively is a, critical issue. This paper describes a load management system for HLA-based distributedsimulation. The system is constructed on top of a Grid Computing environment supported by Globus. The overall structure of the system is presented in the paper and how the system saves and restores a federate is also discussed in detail.
parallel and distributed discrete-event simulation (PDES) is a critical technology for an important class of very large complicated simulation models. However, with few exceptions, the bulk of empirical work in PDES h...
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parallel and distributed discrete-event simulation (PDES) is a critical technology for an important class of very large complicated simulation models. However, with few exceptions, the bulk of empirical work in PDES has been on small models. Furthermore, synchronization behavior is frequently complicated, which makes it very difficult to analytically prove anything about the performance executing large models on large machines. Scalability analysis asks how the performance of a certain application behaves as the application problem size increases and the parallel architecture executing it increases.
A new partitioning method for synchronous PDES simulations is proposed. The method exploits characteristics of both the simulation method and of the application domain to arrive at efficient partitionings. A performan...
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A new partitioning method for synchronous PDES simulations is proposed. The method exploits characteristics of both the simulation method and of the application domain to arrive at efficient partitionings. A performance study shows that the method outperforms existing partitioning methods in terms of four different performance metrics.
With parallel and Discrete Event simulation (PDES) techniques, the runtime performance of detailed wireless network simulation can be improved significantly without compromising fidelity of the simulation results. How...
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ISBN:
(纸本)0769521118
With parallel and Discrete Event simulation (PDES) techniques, the runtime performance of detailed wireless network simulation can be improved significantly without compromising fidelity of the simulation results. However modelling characteristics of wireless communications such as signal propagation and interference may severely hinder the potential speedup yielded by PDES. This paper proposes various optimization techniques to address three major concerns in achieving efficient parallel execution of wireless network simulation: i.e., (1) reducing communication and computation overhead of simulating signal propagation across multiple logical processes;(2) reducing synchronization overhead among logical processes;(3) minimizing event scheduling overhead within individual logical processes. These techniques have been implemented in a parallel version of GloMoSim and QualNet. The experimental results with mobile ad hoc networking scenarios demonstrate that the proposed optimization techniques can improve the performance of parallel wireless network simulation by up to an order of magnitude.
One of the key factors for efficiency in distributedsimulation is the detection of model-inherent concurrency, which is related on the prediction of the future behavior of each logical simulation process. In this pap...
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One of the key factors for efficiency in distributedsimulation is the detection of model-inherent concurrency, which is related on the prediction of the future behavior of each logical simulation process. In this paper we present a generalization of traditional approaches to behavioral prediction which provides more accurate predictions in general and a high degree of scalability in terms of computational and communication overhead. We give a sequential implementation, prove its correctness using concepts from the analysis of real-time process networks and then show how these results can be used in distributedsimulation.
Motion planning is a fundamental problem in a number of application areas, including robotics, automation, and virtual reality! This paper describes a parallel implementation of a motion planning algorithm particularl...
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ISBN:
(纸本)0769500595
Motion planning is a fundamental problem in a number of application areas, including robotics, automation, and virtual reality! This paper describes a parallel implementation of a motion planning algorithm particularly suited for complex systems characterized by many degrees of freedom. nle implementation is based on the concurrent exploration of the search space by a randomized planner replicated on each node of the parallel architecture. All processing elements compete to obtain a solution over the entire search space in an OR-parallel fashion, Reported results refer to a low-cost cluster of PCs and an SGI Onyx2 parallel machine. The experiments emphasize the effectiveness of the approach for complex, high-dimensionality planning problems.. We believe that the approach may, be useful in other complex search problems, especially when the parallel architecture exhibits relatively high communication latency.
The parallel (and distributed) Discrete Event simulation (PADS) community - over it's more than 20 years of existence has achieved remarkable results in getting the execution of simulations of discrete event syste...
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ISBN:
(纸本)0769521118
The parallel (and distributed) Discrete Event simulation (PADS) community - over it's more than 20 years of existence has achieved remarkable results in getting the execution of simulations of discrete event systems faster, involving multiple, logically and/or physically dispersed, communicating computational resources. A solid, mature and empirically approved body of foundational concepts, models, systems, methods and algorithms are at hand and well documented in more than 50.000 pages of research papers. PADS simulation engines, model and software libraries, and operating systems have proven feasibility and applicability of these results in solving real world problems. Despite the (healthy) self-criticism of it's proponents ("Will the field survive?"), PADS was - and is - a success! With this talk we aim at a prospect for the challenges posed by the emerging new models of computational and communication, the evolving new paradigms of interaction and coordination, the new styles of system design, and even the availability of new technologies, for which - in my opinion - no other community qualifies better than the PADS community.
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