Course Software Engineering II academic year 2007 -2008

Course: Software Engineering II academic year: 2007 -2008 Course Web-site: [www. di. univaq. it/cortelle/] Lecture 22: Performance Evaluation with SHARPE Lecturer: Catia Trubiani Computer Science Department University of L'Aquila - Italy Catia. trubiani@di. univaq. it

Copyright Notice » The material in these slides may be freely reproduced and distributed, partially or totally, as far as an explicit reference or acknowledge to the material author is preserved. SEA Group 2

Roadmap Performance modeling Generalized Stochastic Petri Nets (GSPNs) SEA Group 3 evaluation Symbolic Hierarchical Automated Reliability and Performance Evaluator (SHARPE)

Software Performance Software developers’ world (vocabulary) is intrinsically distant from performance analysts’ one. SEA Group 4 APPLICATION MODEL APPLICATION PERFORMANCE MODEL

Performance Notations Queueing Network s Markov processe s Generalized Stochastic Petri Nets Stochastic Process Algebras Simulation SEA Group 5

SHARPE: screenshot Symbolic Hierarchical Automated Reliability and Performance Evaluator (SHARPE) SEA Group 6

SHARPE evaluation Steps for Performance evaluation with SHARPE: § Design of a generalized stochastic Petri net model § Definition of constants, variables and functions § Analysis of the model § Plotting the results of a model SEA Group 7

1 - Sharpe design § Design of a generalized stochastic Petri net model producer SEA Group 8 tasks consumer

2 - Sharpe definitions § Definition of constants, variables and functions producer tasks consumer lambda, buffer. Size, mu SEA Group 9

3 - Sharpe analysis § Analysis of the model § Steady-state average number of tokens in the given place § Steady-state THROUGHPUT for a transition § Steady-state UTILIZATION for a transition § Steady-state probability that the given place is empty SEA Group 10

4 - Sharpe plotting § Plotting the results of a model different rates for the transition “consumer” SEA Group 11

Exercise Comparison of two simple models: (1) producer tasks consumer 2 (2) producer SEA Group 12 consumer 1 tasks consumer 3

System Performance Model Results § Plotting the results of the models… Throughput of consumers in comparison, what’s the meaning of gaps? SEA Group 13

Basic Readings » [Performance evaluation] http: //www. ee. duke. edu/~kst/ Software packages, Sharpe, Tool and Interface Manual Robin Sahner, Kishor S. Trivedi, Antonio Puliafito “PERFORMANCE AND RELIABILITY ANALYSIS OF COMPUTER SYSTEMS” SEA Group 14