Middleware-based adaptation evolution with reusable adaptation

196 Pages·2012·4.96 MB·English

Faculteit Wetenschappen
Departement Wiskunde & Informatica

Middleware-based adaptation evolution with reusable
adaptation components

Jury: Dissertation submitted to the graduate
Prof. Dr. Jan Broeckhove, chairman faculty of University of Antwerp in
Dr. Vincenzo De Florio, promoter partial fulfilment of the requirements for
Prof. Dr. Chris Blondia, co-promoter the degree of DOCTOR of
Prof. Dr. Francky Catthoor PHILOSOPHY
Prof. George Papadopoulos
Porf. Serge Demeyer
For

Ning Gui

Recommended for Acceptance
by the Department of Mathematics and Computer Science
September, 2012
© Copyright by

Ning Gui

All Rights Reserved

2012
Abstract

With recent development of mobile and pervasive computing, software applications are
increasingly expected to dynamically adjust their behaviours according to the highly
dynamic environments they are deployed in Applications must sense the environment
changes and reacting upon those changes based on their contextual knowledge. For each
new context, a new adaptation logic is required. This results in the high complexity of
adaptive software development, especially for changing environments.
Multiple approaches have been proposed to facilitate the development of adaptive
systems. However, such works mostly focused on providing support for particular set of
systems and with pre-defined quality-of-service optimization goals. Therefore, they are
costly to reuse in new systems and hard to adjust to other concerns. How to streamline the
engineering of adaptation with multiple and evolving combinations of concerns remains a
largely unexplored topic.
This work addresses this issue from two aspects: Firstly, a novel adaptive framework is
proposed by extending the separation of concerns paradigm to adaptation logics design.
System’s global adaptation behaviour is contextually constructed with multiple reusable
adaptation modules each of which embeds an adaptation strategy limited to one or more
concerns. Rather than assuming these strategies to be orthogonal and thus not interfering
with each other, this framework provides a systematic and customizable conflict detection
policy and resolution mechanism. Secondly, a modular middleware architecture is
designed to facilitate the incremental deployment of new and unforeseen adaptation
modules. Software engineers are provided with the ability to add/remove/update adaptation
modules during run-time. Development of adaptation modules is simplified by factoring
out common adaptation mechanisms.
Our approach, embodied in an adaptation framework called Transformer, provides an
engineering approach to monitor a target system and its environment, detect opportunities
for improvements, select a course of adaptation strategies, resolve possible conflicts and
apply changes to a software architecture. Our work was compared to the state of the art
from both theoretical and practical viewpoints. Design evaluation and experiment results
show that our system has significant advantage over traditional approaches in light of
flexibility and reusability of the adaptation modules, with little complexity and
performance overhead. Moreover, our framework was applied in a practical case study –
autonomous robots control. Experience gained from this case justified that both the
framework design and modular middleware-based implementation add significant value to
developers in designing and incorporating new adaptation logics.

I

ACKNOWLEDGEMENTS

In the whole course of PhD experience, the most challenging part, I think, is the thesis
writing period. I was not so well-prepared in the beginning to write such a big “book”.

Sweat and passion was spent and lessons were learned. After the course of misery and
harvest, I finally made it. Now, I have a thesis truly belongs to my own.
Of course, a PhD thesis is never the result of a single person’s effort. It would not have
been possible without the support of many different people who help me from different
perspectives. First of all, I would like to thank my advisor, Dr. Vincenzo De Florio, who
provided his kindest support, understanding and encourage throughout my whole PhD
research. I also want to express my gratitude to my co-promoter, Prof. dr. Chris Blonda,
your consistent supports give the courage to live through those hardest time. The jury
members of my PhD thesis committee also give me very important advices. Here, I will
give me deepest thanks to you: Professors George A. Papadopoulos, Francky Catthoor,
Jan Broeckhove and Serge Demeyer. Your support helps me go through the most difficult
period in my life. I would give my special thanks to Prof. Tom Holvoet for your help and
support.
Special thanks to my PATS friends Johan, Bart, Erwin, Nik, Michael, Kathleen, Nicolas
etc. They also provided me with a great working environment and help me out of many
personal problems. I enjoyed very much the time we spent together. Additionally, I would
like to thank my friends, Jiwei, Xianglan, Ming for making the lunch breaks and other free
times in the last few years so interesting and revitalizing.
My family is my most important of my thesis. My parents, Chengwang and Dongmei ,
give me their selfless-support and endless-trust. I would also like to give my thanks to my
son –Wenfeng, who gives me endless happiness writing. Most importantly, I would like to
give special thanks to my loving wife, Zhifeng. Your support and understanding help me go
through the many sleepless nights and the difficulties in the thesis evaluation.

Ning Gui
Leuven, 2012

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Contents
Chapter 1 Introduction ......................................................................... 1
1.1 Thesis motivation ...................................................................................... 1
1.2 Engineering adaptation modules ............................................................... 6
1.3 Thesis statement & contributions .............................................................. 8
1.4 Thesis innovations .................................................................................... 8
1.5 Methodology and implementation ............................................................ 9
1.6 Thesis outline .......................................................................................... 10
Chapter 2 Preliminaries .....................................................................13
2.1 Basic concepts and definitions ................................................................ 13
2.2 Basic design methodology ...................................................................... 20
2.3 Adaptation with composable adaptation modules .................................. 23
2.4 Conclusion .............................................................................................. 27
Chapter 3 Related Work .......................................................................29
3.1 Supporting disciplines ............................................................................. 30
3.2 Related middleware-based self-adaptation approaches .......................... 34
3.3 Limitations of the surveyed approaches ................................................. 41
3.4 Conclusions ............................................................................................. 45
Chapter 4 Transformer Adaptation Framework .............................47
4.1 Motivation example ................................................................................ 48
4.2 Application composition with multiple contextual concerns .................. 50
4.3 System architecture model ...................................................................... 53
4.4 Component management layer ............................................................... 56
4.5 Adaptation layer ...................................................................................... 59
4.6 System adaptation route .......................................................................... 61
4.7 Conclusions ............................................................................................. 66
Chapter 5 A Reflective and Modular Middleware Architecture
for Run-time Adaptation Composition ...................................................67
5.1 Introduction ............................................................................................. 68
5.2 DRCom component model ..................................................................... 69
5.3 System key modules ............................................................................... 80
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Contents
5.4 Middleware architecture ......................................................................... 89
5.5 Case studies ............................................................................................. 92
5.6 Simulation and comparison..................................................................... 95
5.7 Discussion ............................................................................................. 107
Chapter 6 Autonomous NXT Robot Control Platform ............... 109
6.1 Introduction ........................................................................................... 109
6.2 Integrate NXT robot into Transformer framework ............................... 111
6.3 Developing the robot explorer application ........................................... 118
6.4 Adaptation behaviours design ............................................................... 123
6.5 Conclusions and future work ................................................................ 136
Chapter 7 Thesis Evaluation ........................................................... 139
7.1 Functional requirements........................................................................ 140
7.2 Non-functional requirements ................................................................ 142
7.3 Comparisons with existing projects ...................................................... 146
7.4 Discussion of design issues and limitations .......................................... 147
7.5 Summary ............................................................................................... 149
Chapter 8 Conclusions and Future Work ........................................ 151
8.1 Summary of contributions..................................................................... 151
8.2 Future work ........................................................................................... 153
Appendix A Structural dependence maintenance algorithm .............. 157
A.1 Event-based Triggering ......................................................................... 157
A.2 Structural dependence resolution .......................................................... 158
A.3 Adaptation action identification ............................................................ 160
Appendix B Simulation on Adaptation with loop detection .............. 163
B.1 Settings of targeted abstract applications .............................................. 163
B.2 Adaptation modules .............................................................................. 163
B.3 Adaptation in stable environment ......................................................... 165
Appendix C Varying CMD and DSM Selection ................................ 167
C.1 Distance based CMD ............................................................................ 167
C.2 CMD Migration and DSM selection ..................................................... 168
Bibliography . ....................................................................................... 171
VI
List of Figures
Figure 1-1. Autonomic adaptation manager – architectural model ...................................... 3
Figure 1-2. Internal and external approaches for building self-adaptive software .............. 5
Figure 2-1. Dynamic evolution of CCG ............................................................................ 16
Figure 2-2. External closed-loop control ........................................................................... 17
Figure 2-3. Meta-adaptation for self-adaptive software .................................................... 23
Figure 2-4. Conceptual model for middleware with multiple adaptation concerns ........... 24
Figure 4-1. Domain-specific adaptation fusion. ................................................................ 49
Figure 4-2. Context-specific application construction flow .............................................. 51
Figure 4-3. Transformer Adaptation framework ................................................................ 54
Figure 4-4. Sensor, Event Reasoner and their relationships .............................................. 56
Figure 4-5. Adaptation loops for system configuration migration. .................................... 63
Figure 5-1. Sample manifest file for DRCom .................................................................... 71
Figure 5-2. Sample DRCom description ............................................................................ 73
Figure 5-3. Life cycle of OSGi bundle, from OSGi specification ..................................... 78
Figure 5-4. Extended OSGi component lifecycle .............................................................. 79
Figure 5-5. DRCom based DSM Manager ........................................................................ 82
Figure 5-6. Service-component based middleware architecture ........................................ 88
Figure 5-7 Sequence diagram for DSM selection .............................................................. 90
Figure 5-8. System variability of the modular middleware ............................................... 91
Figure 5-9. TV application Construction ........................................................................... 94
Figure 5-10. TV Performance adaptation .......................................................................... 95
Figure 5-11. Framework performance on adding one new component ........................... 100
Figure 5-12. Performance of Model Fusion ..................................................................... 102
Figure 5-13. Memory Consumption ................................................................................ 104
VII
List of Figures
Figure 5-14. Process Video Frames with Human/DSM based Healing ........................... 105
Figure 5-15. Execution time (Adaptation vs. no-Adaptation) ......................................... 106
Figure 6-1. A picture of an assembled NXT robot ........................................................... 111
Figure 6-2. Remote NXT model ...................................................................................... 113
Figure 6-3. Remote NXT model – Touch Sensor ............................................................ 114
Figure 6-4. Sensor, ICommand and their relationship ..................................................... 115
Figure 6-5. Application structures for different contexts ................................................. 119
Figure 6-6. The class hierarchy of the Battery EventReasoner........................................ 126
Figure 6-7. Dynamic UI ................................................................................................... 135
Figure 6-8. Bundle control and monitoring ..................................................................... 136
Figure 6-9. Run-time installing new components ............................................................ 137
Figure B-1. Adaptation steps under static context environment ...................................... 166
Figure C-1. CMD for two DSMs with two context factors: CPU and Battery ................ 168
Figure C-2. DSM selection zone with selection threshold 0.3 ........................................ 169

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