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Parameter Dependencies
for Component Reliability Specifications
Heiko Koziolek (ABB Corporate Research)
Franz Brosch (FZI Karlsruhe, Germany)
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 1
EU Project Q-ImPrESS
Quality
Impact
Prediction for
Evolving
Service-oriented
Software
www.q-impress.eu
Software Reliability
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 2
“The probability of failure-free operation of a program for a specified period of time
in a specified environment.”[Musa1987]
Architecture-based Reliability Analysis
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 3
Markov Model
R = 0.9223
Expected Reliability Markov Model Solution[Trivedi2001]
1
Failure Probability = 0.0022
2
Failure Probability = 0.0012
3
Failure
Probability
= 0.0031
Component Architecture
Problem
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 4
How to determine the transition probabilities?
Literature: Existing Approaches
R. Cheung 1980 (IEEE TSE)
• Transition probabilities via measurements
Hamlet 2001 (ICSE)
• Transition probabilities via measurements
Reussner 2003 (JSS Vol. 66 No.3)
• Assumes transition probabilities as given
L. Cheung 2008 (ICSE)
• Assumes no control flow propagation
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 5
Our Solution
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 6
Our Solution: Model
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 7
Internal Action
Sequence
External Call
Branch
Branch Probability
Our Solution: Model
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 8
Failure Probability
External
Call
Inputs Input
Parameter
Parameter
Dependency Input
Parameter
Parameter
Dependency
Branch Probability
Our Solution: Model
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 9
Loop
Number of Iterations
Our Solution: Model
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 10
Our Solution: Transformation
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 11
Our Solution: Markov Model Solution
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 12
Q R
[Trivedi2001]
Case Study: Retail Management System
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 13
Case Study: Inventory Service - Book Sale
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 14
Case Study: Modelling
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 15
Component
Architecture
Control Flow Graph
for a Component Service
Parameter Dependency
on Loop Count
Palladio
Tool
Case Study: Analysis
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 16
Markov Model Solution
Palladio
Tool
Case Study: Reliability Prediction Results
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 17
Case Study: Reliability Prediction Results
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 18
Assumptions & Limitations
Markov Property
Failure Probabilities
Determiniation?
Stochastically Independent
Constant
Expressiveness
No Hardware Failures
No Concurrency
No Repair
Getting Parameter
Dependencies
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 19
Conclusion
Parameter Dependencies for
Component Reliability Specifications
Modelling by component developer
and software architect
Easy alternation
of system-level usage profile
Reusable reliability specifications
Heiko Koziolek: Parameter Dependencies for Component Reliability Specifications 20
www.q-impress.eu
