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...
详细信息
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.
Modelling and simulation permeate all areas of business, science and engineering and increasingly complex simulation systems often require huge computing resources and data sets that are geographically distributed. Th...
详细信息
In this work we define and test a new framework obtained as the integration of two recently developed middlewares defined to support the parallel and distributedsimulation of large scale, complex and dynamically inte...
详细信息
ISBN:
(纸本)0769522327
In this work we define and test a new framework obtained as the integration of two recently developed middlewares defined to support the parallel and distributedsimulation of large scale, complex and dynamically interacting system models (like wireless and mobile network systems). In a distributedsimulation of highly interacting system models, the main bottleneck may become the communication and synchronization required to maintain the causality constrains between distributed model components. We designed and implemented the ARTIS middleware as a new framework incorporating a set Of features that allow an adaptive optimization of the communication layer management in a distributedsimulation scenario. ARTIS has been integrated with GAIA, a dynamic mechanism for the runtime management and adaptive allocation of model entities in a distributedsimulation. By adopting a runtime evaluation of causal bindings between model entities GAIA adapts the dynamic and time-persistent causal effects of model interactions to dynamic migration of model entities. Preliminary results demonstrate that the combined effect of ARTIS management and GAIA heuristics leads to a significant reduction in the communication and synchronization overheads between the physical execution units. simulation performance enhancements have been obtained also in worst-case modelling assumptions and simulation scenarios.
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...
详细信息
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...
详细信息
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.
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...
详细信息
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.
In previous work we have introduced JavaSymphony, a system whose purpose is to simplify the development of distributed and parallel Java applications. JavaSymphony is a Java library that allows to control parallelism,...
详细信息
ISBN:
(纸本)076951880X
In previous work we have introduced JavaSymphony, a system whose purpose is to simplify the development of distributed and parallel Java applications. JavaSymphony is a Java library that allows to control parallelism, load balancing, and locality at a high level. Objects can be explicitly distributed and migrated within virtual architectures, which impose a virtual hierarchy on a distributed system of physical computing nodes. In this paper we present the design of the JavaSymphony Runtime System and the JavaSymphony Shell. Moreover we discuss details about an agent-based implementation of the JavaSymphony Runtime System which comprises the Network Agent, Object Agent, and Event Agent. We present a detailed comparison of the functionality provided by JavaSymphony with several related systems.
The simulation of incompressible fluids is one of the important problem classes in computational fluid dynamics. We consider a simulation algorithm for the convection in binary fluid mixtures, a problem where a quite ...
详细信息
ISBN:
(纸本)0769500595
The simulation of incompressible fluids is one of the important problem classes in computational fluid dynamics. We consider a simulation algorithm for the convection in binary fluid mixtures, a problem where a quite simple model describes a very complex behavior: In a parallel implementation on an IBM SP2, we investigate several implementation strategies involving different data layouts and communication organizations.
We propose a new simulation method, called interval branching, which aims to facilitate efficient simulation studies of systems that involve temporal uncertainty. The method uses interval timestamps for events and exp...
详细信息
ISBN:
(纸本)9780769531595
We propose a new simulation method, called interval branching, which aims to facilitate efficient simulation studies of systems that involve temporal uncertainty. The method uses interval timestamps for events and explores different execution orders of overlapping events by branching the simulation. We first present a sequential version of interval branching, and then extend it to parallelsimulation using the logical process paradigm. The parallel interval branching algorithm uses the logical-process cloning technique for efficient computation of branches. Our preliminary experiments show its potential as an efficient method for discrete-event simulation studies.
The notion of temporal uncertainty, expressed as the possibility for an event to occur in an interval of simulation time, rather than at a specific instant, has been recently proposed and exploited in order to enhance...
详细信息
ISBN:
(纸本)0769521118
The notion of temporal uncertainty, expressed as the possibility for an event to occur in an interval of simulation time, rather than at a specific instant, has been recently proposed and exploited in order to enhance the performance of parallel/distributedsimulation systems. In this paper we propose the concept of "spatial uncertainty" expressed as the possibility for a simulation event to occur in one of a set of points within the simulated system space. How to handle/exploit space uncertain events in an optimistic simulation system is discussed. Also, experimental results for optimistic simulations of a Personal Communication System (PCS) modeled with space uncertain events are reported These results show the ability of spatial uncertainty to increase the performance of the parallelsimulation system by providing a more flexible approach to synchronization.
暂无评论