Università degli Studi dell’Aquila
Symposium on Software Performance
Joint Kieker/Palladio Days 2013
27-29 November, Karlsruhe, Germany
Catia Trubiani
Dipartimento di Ingegneria e Scienze dell'Informazione e
Matematica (DISIM), University of L’Aquila, Italy
http://www.di.univaq.it/catia.trubiani
A common thought
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
2
What happens today
“apple”
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
3
Technology and its drawbacks
4
problem
solution
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
A proactive approach…
… get rid of worms before
contaminating the apple!
Software (Performance)
Antipatterns
Two main challenges:
1- Identify when a software system is (performance) sick
2- Fix the issues to get (performance) improvements
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
5
(Performance) Antipatterns
»
Negative features of a software system
» Conceptually similar to design
patterns: recurring solutions to
common design problems
» The definition includes common
mistakes (i.e. bad practices) in
software development as well
as their solutions
» What to avoid and how to solve (performance) problems!
W.J.Brown, R.C. Malveau, H.W. Mc Cornich III, and T.J. Mowbray.
“Antipatterns: Refactoring Software, Architectures, and Project in Crisis”, 1998.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
6
Outline of this talk
» Problem statement
» Reasoning on Performance Antipatterns
» Performance Antipatterns in Modeling
Languages

Unified Modeling Language (UML)

Domain Specific Language (PCM)

Architecture Description Language (AEmilia)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
7
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
PROBLEM STATEMENT…
AND DIFFERENT WAYS TO APPROACH IT…
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
8
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
9
» Software performance process
Modeling
(Annotated) Software
Architectural Model
Analysis
Model2Model
Transformation
e.g. UML+Marte, Automata,
Process Algebras, PCM, …
Refactoring
Performance
Model
e.g. Queueing Networks,
Simulation Models, …
Model Solution
PERFORMANCE
RESULTS
COMPLEXITY
-Numbers to be
interpreted
-Different levels of
granularity
Performance
Results
- Cross-checking of
software system
characteristics
Results Interpretation &
Feedback Generation
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Software architectural models
10
UML Component Diagram
UML Use Case Diagram
UML Deployment Diagram
Architectural
specification
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Performance results
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
11
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Software architectural models vs Performance results
The interpretation of performance
results is not a trivial task!
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
12
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
13
Software Performance Feedback: state-of-the-art
Antipatternbased
Design Space
Exploration
Rule-based
Simple
Criteria
Metaheuristics
Approach
(Annotated) Software
Architectural Model
Performance Model
Framework
Williams et al. 2002
Software Execution Model
System Execution
Model
SPE-ED
……
……
……
……
Parsons et al. 2008
JEE systems
Reconstructed runtime
model
PAD
Barber et al. 2002
Domain Reference Arch.
Simulation Model
RARE /ARCADE
……
……
……
……
Xu 2010
UML
Layered QN
Perf. Booster
Zheng et al. 2003
UML
Simulation Model
-
……
……
……
……
Ipek et al. 2008
Artificial Neural Network
Simulation Model
-
Canfora et al. 2005
Workflow Model
Workflow QoS Model
-
……
……
……
……
Martens et al. 2010
PCM
Simulation Model
PerOpteryx
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
14
Antipattern-based approaches
- They make use of antipatterns
knowledge to cope with
performance issues
Williams, L.G., Smith, C.U.: PASA(SM): An Architectural Approach to Fixing
Software Performance Problems. In: International Computer Measurement
Group Conference, Computer Measurement Group (2002)
…
Parsons, T., Murphy, J.: Detecting Performance Antipatterns in Component
Based Enterprise Systems. Journal of Object Technology 7 (2008)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Rule-based approaches
- They encapsulate general
knowledge on how to improve
system performance into
executable rules
Barber, K.S., Graser, T.J., Holt, J.: Enabling Iterative Software
Architecture Derivation Using Early Non-Functional Property Evaluation.
In: ASE, IEEE Computer Society (2002)
…
Xu, J.: Rule-based automatic software performance diagnosis and
improvement. Perform. Eval. 67 (2010)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
15
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
16
Design space exploration – simple criteria
- They explore the design space by
examining alternatives that can
cope with performance flaws
Zheng, T., Woodside, C.M.: Heuristic optimization of scheduling and
allocation for distributed systems with soft deadlines. In Computer
Performance Evaluation /TOOLS (2003)
…
Ipek, E., McKee, S.A., Singh, K., Caruana, R., de Supinski, B.R., Schulz, M.:
Efficient architectural design space exploration via predictive modeling.
ACM Trans. on Architecture and Code Optimization (2008)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Design space exploration – Metaheuristics
- They make use of evolutionary
algorithms that look for design
alternatives aimed at improving
the system performance
Canfora, G., Penta, M.D., Esposito, R., Villani, M.L.: An approach for QoSaware service composition based on genetic algorithms. In Beyer, H.G.,
O'Reilly, U.M., eds.: GECCO, ACM (2005)
…
Martens, A., Koziolek, H., Becker, S., Reussner, R.: Automatically improve
software architecture models for performance, reliability, and cost
using evolutionary algorithms. In WOSP/SIPEW (2010)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
17
Problem
Reasoning on
Perf. Antipat.
Antipatternsbased
Rule-based
…
PA in Modeling
Languages
18
Approach
(Annotated) Software
Architectural Model
Performance
Model
Framework
Williams et al. 2002
Software Execution Model
System Execution
Model
SPE-ED
……
……
……
……
Parsons et al. 2008
JEE systems
Reconstructed
runtime model
PAD
Focus of
this talk
Unified Modeling
Language (UML),
Palladio Component
Model (PCM),
AEmilia ADL
Queueing
Network,
Simulation
Model,
Markov Chain
Performance
Antipatterns
aNd feeDback on
software
Architectures
(PANDA)
Barber et al. 2002
Domain Reference Arch.
Simulation Model
RARE /ARCADE
……
……
……
……
Xu 2010
UML
Layered QN
Perf. Booster
……
……
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
19
Software performance process: introducing automation
Modeling
(Annotated) Software
Architectural Model
Analysis
Model2Model
Transformation
Refactoring
Performance
Model
Model Solution
Antipattern-based
Performance
Rules
and Actions
Antipatterns
Performance
Results
Detection
& Solution of
Results Interpretation
&
Performance
Antipatterns
Feedback Generation
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
20
A bird’s-eye look to the problem
…
1- Representing
Antipatterns
2- Detecting
Antipatterns
3- Solving
Antipatterns
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Representing Antipatterns:
What are the software architectural model elements we
need for representing antipatterns?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
21
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Detecting Antipatterns:
How to explore the architectural models
to recognize antipattern occurrences?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
22
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
23
…
Solving Antipatterns:
What are the refactoring actions that lead the
architectural model to remove performance flaws?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
REASONING ON
PERFORMANCE ANTIPATTERNS
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
24
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
25
Software Performance Antipatterns Classification
Antipattern
Singlevalue
Concurrent
Processing
Systems
Unbalanced
Processing
Solution
Processing cannot make Restructure software or change
use of available
scheduling algorithms to enable
processors.
concurrent execution.
The slowest filter in a
“pipe and filter”
“Pipe and Filter”
architecture causes the
Architectures
system to have
unacceptable throughput.
Extensive
Break large filters into more
stages and combine very small
ones to reduce overhead.
Extensive processing in
general impedes overall
response time.
Move extensive processing so
that it doesn’t impede high
traffic or more important work.
…
…
…
The Ramp
Occurs when processing
time increases as the
system is used.
Select algorithms or data
structures based on maximum
size or use algorithms that
adapt to the size.
Processing
Multiplevalues
Problem
C. U. Smith and L. G.Williams. “More new software performance antipatterns:
Even more ways to shoot yourself in the foot”, 2003.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
26
Single-value vs Multiple-values
» Single-value: performance indices are evaluated in a
certain interval, i.e. the mean, max or min values.
∆
time
» Multiple-values: performance indices are evaluated along
the time, i.e. the values trend (or evolution).
∆
2∆
…
n∆
time
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
27
SPA: why are they complex?
C. U. Smith and L. G.Williams. “More new software performance antipatterns:
Even more ways to shoot yourself in the foot”, 2003.
Antipattern
Blob
…
Problem
Solution
Occurs when a single class or
component either 1) performs
Refactor the design to
distibute intelligence
most of the work of an
application or 2) holds all of
uniformly over the
the applications data. Either
applications top-level
manifestation results in
classes, and to keep related
excessive message traffic data and behavior together.
that can degrade performance.
…
…
What does it mean “most” of the work”?
What does it mean “excessive” message traffic?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
How to make more “formal”
(i.e. machine-processable)
the specifications of
antipatterns???
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
28
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
29
Graphical representation of the “Blob” Antipattern
PROBLEM: “occurs when a single class or component either 1) performs most of the
work of an application or 2) holds all of the applications data. Either manifestation
results in excessive message traffic that can degrade performance”
(Annotated) Software
Architectural Model M
(Annotated) Software
Architectural Model M
i
i
i
i
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
30
Graphical representation of the “Blob” Antipattern
SOLUTION: “Refactor the design to distribute intelligence uniformly over the
applications top-level classes, and to keep related data and behavior together”
(Annotated) Software
Architectural Model M’
(Annotated) Software
Architectural Model M’
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
31
Idea: building a vocabulary to include all model elements
involved in the antipatterns specification
Views overlapping!
Message
STATIC VIEW: software resources,
relationships among them, …
to model static aspects
DYNAMIC VIEW: interactions such as
messages between sw resources, …
to model dynamic aspects
senderRole
SoftwareEntity
Instance
receiverRole
DYNAMIC
VIEW
DEPLOYMENT VIEW: hardware resources, …
to model deployment aspects
ProcesNode
utilization
deployedInstance
clientRole
DEPLOYMENT
VIEW
supplierRole
Relationship
STATIC
VIEW
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
32
PAML: Perf.Antipatterns Modeling Language
READ: Reference Elements for
Antipatterns Definition
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
The “Model Elements Specification” sub-MM: READ
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
33
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
34
Basic Idea: a performance antipattern can be formalized as
a logical predicate LPantipatName
A logical predicate is made of (Static, Dynamic,
Deployment) basic predicates, BPi
LPantipatName = BP1 (∧, ∨) … (∧, ∨) BPn
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
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Perf. Antipat.
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35
Auxiliary elements in the formalization process
Functions
> FfunctionName elaborates information of the model
(e.g. FnumMsgs is a function counting the number of messages sent by
an instance of the class/component model element)
Thresholds
> ThthresholdName is a value used to establish the acceptable range of
values for system features
(e.g. ThmaxMsgs is a threshold value representing the upper bound for
an acceptable number of messages exchanged among two software
instances. It can be estimated, for example, as the average number
of all messages sent by all software entities, plus the
corresponding variance)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
36
The Blob antipattern occurs when the following predicate is true:
(
∨
)
(
∧
∨
)
(
∨
where
represents the set of SoftwareEntityInstance(s), and
represents the set of Service(s).
All the (swEx, swEy, S) instances satisfying the predicate must be
pointed out to the designer for a deeper analysis.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
∧
)
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Thresholds in performance antipatterns
specification/representation
Design : thresholds
Performance :
referring to design
thresholds referring to
characteristics (e.g.
performance indices
Overview
of(e.g.
Antipatterns
Thresholds
high/low number
of
high/low device
connections, number of utilization, queue length).
exchanged messages).
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
37
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Each antipattern can be
expressed by means of
first-order logics
But this is only OUR
interpretation of their
textual description
V. Cortellessa, A. Di Marco, and
C. Trubiani. “An approach for
*seemodeling
more details
in:
and detecting
Software Performance
Antipatterns based on firstorder logics”, accepted for
publication in the journal of
Software and Systems Modeling
(SoSyM), 2012.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
38
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Key-Question:
Once we have (somehow) “represented” antipatterns,
how can we detect them in a software model?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
39
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
How to establish fair
thresholds for antipatterns???
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
40
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Define heuristics to calculate antipatterns
thresholds
E.g., ThmaxConnects can be
estimated as the average
number of connections
per component, by
considering the entire
set of software
components in the
software system, plus
the corresponding
variance.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
41
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
42
A case study: the “E-commerce System”
software model excerpt
performance model
Requirement
Required Value
Predicted Value
RT(browseCatalog)
1.2 sec
1.5 sec
RT(makePurchase)
2 sec
2.77 sec
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
43
A preliminary complex step: setting thresholds
Detecting Antipatterns
design properties
(e.g. excessive message traffic)
performance results
(e.g. high network utilization)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
44
Performance Antipattern occurrences in ECS:
Detecting Antipatterns
Antipattern
Blob
Problem
Solution
libraryController performs most of Refactor the design to keep related data and
the work, it generates excessive
behavior together, i.e. delegate some work
message traffic towards bookLibrary
from libraryController to bookLibrary
Concurrent
Processing Systems
Processing cannot make use of the
processor webServerNode
Restructure software or changing scheduling
algorithms between processors libraryNode
and webServerNode
Empty Semi
Trucks
An excessive number of requests are
sent by the userController to perform
the task of registering users
Refactor the design combining items into
messages to make better use of available
bandwidth
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Detecting Antipatterns
» An example: detecting the EST antipattern instance
The (userController,
RegisterUsers)
instance satisfies
the Empty Semi
Trucks predicate,
hence it must be
pointed out to the
designer for a
deeper analysis
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
45
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
And another Key-Question
Once we have (somehow) “detected” antipatterns,
which refactoring actions must be taken
to remove (some of) them?
First rough approach
First-Order-Logic representation of antipatterns can help:
refactoring actions can be (automatically)
obtained from negating predicates!
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
46
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
47
Solving Antipatterns
An example: solving the EST antipattern instance
The removal of the
EST antipattern gives
rise to a new software
architectural model
(called here as
“ECS \ {est}”)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
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48
Performance Analysis of some
refactored models
Analysis
Modeling
ECS \ {est}
ECS \ {cps}
Prima-UML
ECS \ {blob}
Queueing
Network
MVA
Response Time,
Utilisation, …
Unified Modeling
Language (UML)
(Annotated) Software
Architectural Model
RT(browseCatalog) < = 1.2 sec
RT(makePurchase) < = 2 sec
ECS
1.5 sec
2.77 sec
ECS \ {blob}
1.14 sec
2.18 sec
ECS \ {cps}
1.15 sec
1.6 sec
ECS \ {est}
1.5 sec
2.24 sec
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
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49
Some more thoughts on refactoring
RBML (Role-Based Modelling Language) defines the available
constructs (roles and associations among them)
characterizes a (part of a) system in
terms of roles that are played by the
elements of the system
characterization of the
(source) model that has to be
refactored
the number of elements
playing that role
characterization of the
refactored (target)
model
It exists a <<T Role>> for each type T in the
modelling language used to specify the system
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
50
Empty Semi Trucks (EST) - SOURCE ROLE MODEL
Elements from the
antipattern detection phase
Contextual elements: additional model
elements that can support the
removal of the bad practice
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Empty Semi Trucks (EST) - TARGET ROLE MODEL
Added
elements
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
51
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
PERFORMANCE ANTIPATTERNS
IN MODELING LANGUAGES
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
52
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
53
Antipattern-based process
(Annotated) Software
Architectural Model
Model2Model
Transformation
Performance
Model
Model Solution
- Generic Modeling
Languages (UML)
- Domain Specific
Languages (PCM)
- Architecture Description
Languages (Aemilia)
-
…
Performance
Results
Antipatterns-based
Rules and Actions
Detecting Antipatterns
(i.e. Results Interpretation)
(Annotated) Software
Architectural Model
Candidate1
Solving Antipatterns
(i.e. Feedback Generation)
…
(Annotated) Software
Architectural Model
Candidaten
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
54
Looking at different modeling notations…
…
UML
Generic Modeling
Language
(i.e. UML +
Marte profile)
representing
Domain Specific
Language
(i.e. Palladio
Component Model)
detecting
solving
...any modeling
language has
“antipatternsconcepts”
AEmilia
PCM
Architectural
Description
Language
(i.e. AEmilia)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
55
MDE support: metamodel and model transformations
…
M1: Models
M2: Metamodels
representing
detecting
solving
...any modeling
language has
“antipatternsconcepts”
Generic Modeling
Language
(i.e. UML +
Marte profile)
Domain Specific
Language
(i.e. Palladio
Component Model)
Architectural
Description
Language
(i.e. AEmilia)
UML model
(Marte annotated)
PCM model
AEmilia
specification
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
56
Antipatterns in concrete modeling languages
Blob
…
Performance Antipatterns
SoftwareEntity
ProcesNode
UML Component
…
UML Node
UML+MARTE
…
PCM Basic Component
…
BasicResDemand
READ
ARCHI_ELEM_TYPE
…
…
PCM Resource Container
Palladio Component Model
Aemilia ADL
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
57
Is UML+Marte expressive enough to specify antipatterns?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Is PCM expressive enough to specify antipatterns?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
58
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Is Aemilia expressive enough to specify antipatterns?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
59
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
60
Expressiveness of the considered modeling languages
UML + Marte profile
Antipattern
Solvable
Detectable
Solvable
Detectable
Solvable
✔
✔
✔
✔
≈
≈
Concurrent
Processing Systems
✔
✔
✔
✖
✖
Pipe and Filter
Architectures
✔
✔
✔
✔
✖
✔
✔
Extensive
Processing
✔
✔
✔
✔
✔
✔
✔
✖
✖
✖
✖
✖
…
…
…
…
…
…
✔
✔
✖
✔
✔
✖
✖
✖
✔
✖
✖
✔
✔
✖
Tower of Babel
…
The Ramp
Traffic Jam
More is Less
AEmilia
Detectable
Blob
Unbalanced
Processing
Palladio Component Model
✔ = fully detectable/solvable
✔
✖
✖
✖
≈ = partially detectable/solvable ✖ = not detectable/solvable
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Open Issues - Basics
−
Gap textual/formal representations
−
Threshold setting
−
Uncertainty/incompleteness in:
> Architectural/Performance models,
antipatterns specifications, input
parameters (e.g., workload, op. profile)
−
Validation on larger model repositories
(industrial case studies)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
61
Open Issues - Advanced
62
−
Evaluating the framework on:
> Precision (ratio of actual antipatterns found)
> Recall (ratio of antipatterns found overall)
−
Language-specific antipatterns (other languages to
experiment?)
−
Antipatterns at the code level
−
Combining approaches (antipatterns with
metaheuristics)
−
Tool construction and integration
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Open Issues – Process related
−
Legacy constraints
−
Conflicting solutions
−
Overlapping solutions (composition)
−
Combination with other quality attributes
(maintenability, reliability, etc…)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
63
Discussion
64
−
Interesting points?
−
Open issues?
−
Threats to validity?
−
Links to other research directions?
−
…
That’s all folks!
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
65
Thank you!
Credits for this
invited talk go to…
Vittorio Cortellessa,
Antinisca Di Marco,
Davide Arcelli,
Romina Eramo,
Alfonso Pierantonio,
Anne Koziolek,
Ralf Reussner
Questions
catia.trubiani@univaq.it
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
66
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Software performance process in deep
67
Termination Criteria:
(Annotated) Software
Architectural Model
…
(i) fulfilment criterion
Performance Antipatterns-based
Rules and Actions
Results
(ii) no-actions criterion
(iii) #iterations
Detecting Antipatterns
(i.e. Results Interpretation)
iteration1
Solving Antipatterns
(i.e. Feedback Generation)
(Annotated) Software
Architectural Model
Candidate1-1
(Annotated) Software
Architectural Model
Candidate1-h
…
…
iterationn
(Annotated) Software
Architectural Model
Candidaten-1
…
(Annotated) Software
Architectural Model
Candidaten-k
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
68
Yet another Key-Question:
How to drive the process of antipattern solution?
Who guarantees that the removal of antipatterns will
lead to “better” performance?
First approach
A guilt-based one, but still many issues to solve!
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
A step ahead in the antipatterns solution
Problem: once performance antipatterns has been detected in a
model, which ones should be solved first?
Solution: introducing scores that allow to order detected
antipatterns on the basis of their guilt
R1
Performance
Antipatterns
…
Rj
Violated
Requirements
PA1
…
PAi
weight
(PAi, Rj)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
69
Validation of the ranking process
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
70
Afterthoughts on experimental results
71
#Candidates
(Antipattern
solution)
#Candidates
(Antipattern
guilt-based
solution)
iteration1
7
4
iteration2
36
25
iteration3
123
93
iteration4
289
217
TOT
455
339
The ranking process led
the system to discard
34% of candidates
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
PERFORMANCE ANTIPATTERNS
IN MODELING LANGUAGES:
OUR EXPERIENCE
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
72
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
73
Our experience in UML
Modeling
Unified Modeling
Language (UML)
Analysis
Prima-UML
Refactoring
Queueing
Network
Mean Value
Analysis
OCL code
Response Time,
Utilisation, …
OCL engine for the
Detection of Antipatterns
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
74
UML model
Service Demand
(input parameters)
Utilization
(output indices)
webServerNode
2.02 msec
27%
libraryNode
7.05 msec
96%
controlNode
3 msec
41%
dbNode_cpu
UML Use Case Diagram
dbNode_disk
UML Component Diagram
15 msec
20%
30 msec
41%
UML Deployment Diagram
Requirement: each hardware resource has not to be used more than 80% under the
mean workload of 70 requests/second concurrently in execution in the system.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
An example: the Blob antipattern as OCL rule
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
75
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
76
Detecting antipatterns in UML
“Blob” Antipattern occurrence
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
77
Solving Antipatterns in UML
Note that these values have changed due to the load re-distribution
Service Demand
(input parameters)
webServerNode
“Blob”
Antipattern removal
Utilization
(output indices)
4.07 msec
61%
libraryNode
5 msec
75%
controlNode
3 msec
41%
dbNode_cpu
15 msec
20%
dbNode_disk
30 msec
41%
Requirement: each hardware resource has not to be used more than 80% under the
mean workload of 70 requests/second concurrently in execution in the system.
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
78
Our experience in PCM
Modeling
Palladio Component
Model (PCM)
Analysis
PCM2SimuCom
Refactoring
Simulation
Models
Simulation
Java code
Response Time,
Utilisation, …
Java engine for the
Detection & Solution of
antipatterns
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
79
PCM model
Requirement
Required Value
Predicted Value
RT(system)
10 sec
18.71 sec
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
An example: the Concurrent Processing Systems
antipattern as Java code
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
80
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Detecting antipatterns in PCM
“Concurrent
Processing
Systems”
Antipattern
occurrence
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
81
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Solving antipatterns in PCM
“Concurrent
Processing
Systems”
Antipattern
removal
<<redeploy>>
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
82
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
83
The solution process in PCM
“Concurrent
Processing
Systems”
Antipattern
removal
<<redeploy>>
required value
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
84
Our experience in AEmilia
Modeling
AEmilia
specification
Analysis
TwoTowers
Refactoring
Markov
chain
TwoTowers
OCL code
Response Time,
Utilisation, …
OCL engine for the
Detection of Antipatterns
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
85
AEmilia specification
Requirement
Required Value
Predicted Value
Throughput(system)
15 reqs/sec
12.19 reqs/sec
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
86
An example: the Extensive Processing antipattern
as OCL code (applied on the AEmilia MM!)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
Detecting antipatterns in AEmilia
“Extensive Processing”
Antipattern occurrence
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
87
Problem
Reasoning on
Perf. Antipat.
PA in Modeling
Languages
88
Solving antipatterns in AEmilia
“Extensive Processing”
Antipattern removal
Requirement
Required Value
Predicted Value
Throughput(system)
15 reqs/sec
18.29 reqs/sec
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
M2: Metamodels
Round-trip process in the AEmilia ADL
Performance Antipatterns Modelling Language (PAML)
AEmilia
Grammar
conform to
Modelling
AEmilia Architectural
specification (file.aem)
PAML[AEmilia] Metamodel
conform to
conform to
conform to
Analysis
Refactoring
AEmilia
Model
AEmilia Performance
specification (file.rew)
Performance
Evaluation
M1: Models
89
Text-to-Model
Transformation
Performance
Results Annotation
AEmilia Performance
results (file.val)
Antipatterns
Solution
Annotated
AEmilia
Model
Antipatterns
Detection
Detected
Antipatterns
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
PAML[AEmilia] metamodel
90
structure of the
AEmilia specification
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Text-to-Model Transformation
AEmilia Grammar
91
transformation rules
conform to
AEmilia Architectural
specification (file.aem)
PAML[AEmilia]
Metamodel
conform to
AEmilia
Model
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Performance Results Annotation
AEmilia Performance
specification (file.rew)
AEmilia Performance
results (file.val)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
92
Antipatterns Detection
OCL code for
the detection of the
Extensive Processing
Antipattern
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
93
Advanced MDE techniques
Embedding Antipatterns neutral concept in concrete
modeling notations
−
Antipatterns are based on a dedicated general purpose
language (SML+)
−
Weaving models can map the concepts of SML+ into concrete
modeling notations (parameter passing)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
94
Advanced MDE techniques
95
REPRESENTATION
A transformation T is generated, starting from the WM,
between the neutral representation of antipatterns and the
concrete modeling language
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Advanced MDE techniques
DETECTION
A transformation T’ is generated, starting from the same
WM, to provide an OCL-based executable semantics
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
96
97
INFLUENCE OF ANTIPATTERNS
THRESHOLDS ON ANTIPATTERNS
DETECTION AND REFACTORING
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
Influence of antipatterns thresholds
»
An illustrative example: E-CommerceSystem (ECS)
Requirement: the RESPONSE TIME for the MakePurchase service
must not exceed 2 seconds (with a workload of 150 customers)
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
98
ECS modeling
99
» Static, Dynamic and Deployment Views
Dynamic View
Static
View View
Deployment
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
ECS- Performance Analysis
100
» Performance Annotations
» Performance Results
2.16
the performance
analysis predicts
that the response
time is equal to
2.16 seconds,
larger than the
required 2 seconds
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
ECS- antipatterns detection and
refactoring
101
» Thresholds binding for the Blob antipattern
Blob
<<deploy>>
Performance Results
1.98
…
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
ECS- influence of thresholds in
antipatterns detection
Variation of Blob Thresholds
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
102
ECS- influence of thresholds in
antipatterns refactoring
Variation of the MakePurchase response time across
different Blob refactorings
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013
103
Open issues
104
» Antipatterns that only include thresholds
related to performance indices are more
difficult to refactor vs antipatterns that
include thresholds related to design features.
» What’s the effectiveness of current
heuristics?
» How to decide the “right” (if any) interval of
values for varying the numerical values of
thresholds?
“SPA challenges: how to get rid of worms before contaminating the apple?”,
Invited talk @ Joint Kieker/Palladio Days, Karlsruhe, Germany, 27-29 November, 2013