Software diversity-based active replication as an approach for enhancing the performance of advanced simulation systems

Active replication has been widely explored to achieve fault tolerance and to improve system availability, especially in service oriented applications. In this paper we explore software diversity-based active replication in the context of advanced simulation systems, with the aim at improving the timeliness for the production of simulation output. Our proposal is framed by the High-Level-Architecture (HLA), namely a middleware based standard for simulation package interoperability, and results in the design and implementation of an Active Replication Management Layer (ARML) targeted to off-the-shelf SMP computing systems. This layer can be interposed in between each simulator instance and the underlying HLA middleware component, in order to support the execution of diversity-based active replicas of a same simulation package in a totally transparent manner. Beyond presenting the replication framework and the design/implementation of ARML, we also report the results of an experimental evaluation on a case study, quantifying the benefits from our proposal in terms of both simulation execution speed and performance guarantees vs tunable software parameters. (Free software releases of ARML can be found at the URL http://www.dis.uniromal.it/~quaglia/software/ARML) © World Scientific Publishing Company

Automatic Algorithm Selection for Complex Simulation Problems

To select the most suitable simulation algorithm for a given task is often difficult. This is due to intricate interactions between model features, implementation details, and runtime environment, which may strongly affect the overall performance. The thesis consists of three parts. The first part surveys existing approaches to solve the algorithm selection problem and discusses techniques to analyze simulation algorithm performance.The second part introduces a software framework for automatic simulation algorithm selection, which is evaluated in the third part.Die Auswahl des passendsten Simulationsalgorithmus für eine bestimmte Aufgabe ist oftmals schwierig. Dies liegt an der komplexen Interaktion zwischen Modelleigenschaften, Implementierungsdetails und Laufzeitumgebung. Die Arbeit ist in drei Teile gegliedert. Der erste Teil befasst sich eingehend mit Vorarbeiten zur automatischen Algorithmenauswahl, sowie mit der Leistungsanalyse von Simulationsalgorithmen. Der zweite Teil der Arbeit stellt ein Rahmenwerk zur automatischen Auswahl von Simulationsalgorithmen vor, welches dann im dritten Teil evaluiert wird

International Journal of Foundations of Computer Science cfl World Scientific Publishing Company SOFTWARE DIVERSITY-BASED ACTIVE REPLICATION AS AN APPROACH FOR ENHANCING THE PERFORMANCE OF ADVANCED SIMULATION SYSTEMS*

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