24 research outputs found
On the Use of Queueing Petri Nets for Modeling and Performance Analysis of Distributed Systems
Predictive performance models are used increasingly throughout the phases of the software engineering lifecycle of distributed systems. However, as systems grow in size and complex-ity, building models that accurately capture the different aspects of their behavior becomes a more and more challenging task. The challenge stems from the limited model expressivenes
Modeling and Prediction of I/O Performance in Virtualized Environments
We present a novel performance modeling approach tailored to I/O performance prediction in virtualized environments. The main idea is to identify important performance-influencing factors and to develop storage-level I/O performance models. To increase the practical applicability of these models, we combine the low-level I/O performance models with high-level software architecture models. Our approach is validated in a variety of case studies in state-of-the-art, real-world environments
From Epidemic to Pandemic Modelling
We present a methodology for systematically extending epidemic models to
multilevel and multiscale spatio-temporal pandemic ones. Our approach builds on
the use of coloured stochastic and continuous Petri nets facilitating the sound
component-based extension of basic SIR models to include population
stratification and also spatio-geographic information and travel connections,
represented as graphs, resulting in robust stratified pandemic metapopulation
models. This method is inherently easy to use, producing scalable and reusable
models with a high degree of clarity and accessibility which can be read either
in a deterministic or stochastic paradigm. Our method is supported by a
publicly available platform PetriNuts; it enables the visual construction and
editing of models; deterministic, stochastic and hybrid simulation as well as
structural and behavioural analysis. All the models are available as
supplementary material, ensuring reproducibility.Comment: 79 pages (with Appendix), 23 figures, 7 table
Infraestructura de càlcul HPC CIMNE
Projecte realitzat al CIMNE, Centre Internacional de Mètodes NumèricsL'objectiu d'aquest projecte és el de renovar integralment la infraestructura de càlcul del CIMNE determinant quins dels equipaments actuals es poden utilitzar, llavors implementant un nou sistema operatiu al clúster, aplicant un gestor de recursos i planificador de treballs centralitzat i
eficaç, proporcionant una documentació completa tant pels usuaris com pels administradors juntament amb procediments estàndard de gestió, millorant la seguretat de tot el conjunt, implementant sistemes de monitorització, determinant alguna plataforma de comunicació i documentació entre usuaris i realitzant dos estudis, un referent a l'arquitectura del hardware i l'altre de consum i sostenibilitat, aspecte que no s'havia tingut en compte fins el plantejament
d'aquest projecte
Telecommunications Networks
This book guides readers through the basics of rapidly emerging networks to more advanced concepts and future expectations of Telecommunications Networks. It identifies and examines the most pressing research issues in Telecommunications and it contains chapters written by leading researchers, academics and industry professionals. Telecommunications Networks - Current Status and Future Trends covers surveys of recent publications that investigate key areas of interest such as: IMS, eTOM, 3G/4G, optimization problems, modeling, simulation, quality of service, etc. This book, that is suitable for both PhD and master students, is organized into six sections: New Generation Networks, Quality of Services, Sensor Networks, Telecommunications, Traffic Engineering and Routing
Model Transformation Languages with Modular Information Hiding
Model transformations, together with models, form the principal artifacts in model-driven software development. Industrial practitioners report that transformations on larger models quickly get sufficiently large and complex themselves. To alleviate entailed maintenance efforts, this thesis presents a modularity concept with explicit interfaces, complemented by software visualization and clustering techniques. All three approaches are tailored to the specific needs of the transformation domain
Self-Adaptive Performance Monitoring for Component-Based Software Systems
Effective monitoring of a software system’s runtime behavior is necessary to evaluate the compliance of performance objectives. This thesis has emerged in the context of the Kieker framework addressing application performance monitoring. The contribution includes a self-adaptive performance monitoring approach allowing for dynamic adaptation of the monitoring coverage at runtime. The monitoring data includes performance measures such as throughput and response time statistics, the utilization of system resources, as well as the inter- and intra-component control flow. Based on this data, performance anomaly scores are computed using time series analysis and clustering methods. The self-adaptive performance monitoring approach reduces the business-critical failure diagnosis time, as it saves time-consuming manual debugging activities. The approach and its underlying anomaly scores are extensively evaluated in lab experiments