Modelio M2T with Jython HT: Hawk M2T with EGL A García-Domínguez et al. Integration of a Graph-Based Model Indexer in Commercial Modelling Tools 23 / 27 Intro Integration Evaluation Conclusions M2T with Hawk: conclusions Indexing time grows linearly with model size Generation time grows logarithmically Hawk+EGL is faster than Modelio+Jython for large models Hawk scales better due to indexing and querying optimizations Modelio+Jython has higher constant overhead Break-even point is ~10k elements For large projects, Hawk is preferable SOFTEAM now uses Hawk for all M2

1. Intro Integration Evaluation Conclusions
Integration of a Graph-Based Model Indexer in
Commercial Modelling Tools
Antonio García-Domínguez, Konstantinos Barmpis,
Dimitrios S. Kolovos, Marcos Aurelio Almeida da Silva, Antonin
Abherve and Alessandra Bagnato
Aston University, University of York, SOFTEAM Cadextan
MoDELS’16
October 7th, 2016
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2. Intro Integration Evaluation Conclusions
Outline
1 Intro
2 Integration
3 Evaluation
4 Conclusions
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3. Intro Integration Evaluation Conclusions
Motivation for this work
MONDO EU project: produced Hawk indexer
Goal: tackle scalability of MDE in its various facets
One product was Hawk, a scalable model indexer:
https://github.com/mondo-project/mondo-hawk
Hawk mirrors fragmented models into NoSQL graphs
SOFTEAM: Constellation collab server needed search
SOFTEAM has 20+ years experience on UML tooling
Modelio is their open-source modelling tool
Joined MONDO due to scalability challenges
Created Constellation: Modelio collab server
Constellation had no search box – need indexing!
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4. Intro Integration Evaluation Conclusions
Motivation for this work
MONDO EU project: produced Hawk indexer
Goal: tackle scalability of MDE in its various facets
One product was Hawk, a scalable model indexer:
https://github.com/mondo-project/mondo-hawk
Hawk mirrors fragmented models into NoSQL graphs
SOFTEAM: Constellation collab server needed search
SOFTEAM has 20+ years experience on UML tooling
Modelio is their open-source modelling tool
Joined MONDO due to scalability challenges
Created Constellation: Modelio collab server
Constellation had no search box – need indexing!
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5. Modelio: SOFTEAM’s modelling tool
Open source, scriptable, UML/BPMN/SysML...
Structure: workspace → projects → fragments (.exml)
Projects can import .ramc libraries (zipped fragments)

6. Intro Integration Evaluation Conclusions
Constellation: SOFTEAM’s collab server
Admin server coordinates
agents and provides web UI
Agent nodes (HTTP/SVN)
access/host fragments
No querying facilities
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7. Intro Integration Evaluation Conclusions
Hawk: NoSQL model indexer
We go from these model files...
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8. Intro Integration Evaluation Conclusions
Hawk: NoSQL model indexer
... to these NoSQL graphs.
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9. Intro Integration Evaluation Conclusions
Hawk: NoSQL model indexer
EPackages → metamodel nodes
EClasses → type nodes
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10. Intro Integration Evaluation Conclusions
Hawk: NoSQL model indexer
.xmi → file nodes
EObjects → element nodes
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11. Intro Integration Evaluation Conclusions
Hawk: NoSQL model indexer
MM index: EPackage URI → metamodel node
File index: repo + file path → file node
Users can define custom indices by attribute/expression
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12. Intro Integration Evaluation Conclusions
Outline
1 Intro
2 Integration
3 Evaluation
4 Conclusions
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13. Intro Integration Evaluation Conclusions
Integration approach
Key detail in Hawk: plugin-based architecture
Hawk has abstraction layers for:
Database backends (Neo4j, OrientDB)
Model persistence formats (XMI, UML, Modelio...)
Query languages (Epsilon Object Language)
Steps taken
1 Expose Modelio metamodels to Hawk
2 Write .exml/.ramc parser
3 Extend Hawk with Modelio specifics
4 Embed into Constellation
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14. Intro Integration Evaluation Conclusions
Initial legal issues
Problem
Hawk is EPL, Modelio is GPLv3: incompatible licenses
Cannot reuse neither metamodel code nor parsing code
Solutions
SOFTEAM wrote M2T transformation to expose metamodels
as Apache-licensed library (ModelioMetamodelLib)
http://github.com/aabherve/modelio-metamodel-lib
Hawk includes transformation to Ecore
Hawk devs collaborated with SOFTEAM to write new parsers
Clean-room approach: no looking at Modelio code!
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15. Intro Integration Evaluation Conclusions
Initial legal issues
Problem
Hawk is EPL, Modelio is GPLv3: incompatible licenses
Cannot reuse neither metamodel code nor parsing code
Solutions
SOFTEAM wrote M2T transformation to expose metamodels
as Apache-licensed library (ModelioMetamodelLib)
http://github.com/aabherve/modelio-metamodel-lib
Hawk includes transformation to Ecore
Hawk devs collaborated with SOFTEAM to write new parsers
Clean-room approach: no looking at Modelio code!
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16. .exml format
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>

17. .exml format: version, dependencies
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Format version
Dependencies

18. .exml format: version, dependencies
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Format version
Dependencies

19. .exml format: root object
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Object name, metaclass, UID
Same UID = same object
Happens when importing libraries
Container UID
EMF compatibility would require
deriving containments

20. .exml format: root object
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Object name, metaclass, UID
Same UID = same object
Happens when importing libraries
Container UID
EMF compatibility would require
deriving containments

21. .exml format: attributes and dependencies
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Attributes: name-value pairs
Dependencies: references
COMPositions (containment?)
LINKs (non-containment)

22. .exml format: attributes and dependencies
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
Attributes: name-value pairs
Dependencies: references
COMPositions (containment?)
LINKs (non-containment)

23. .exml format: nested objects
<EXT object="Component" version="3">
<DEPS>
<ID name="Component" mc="Class" uid="2d7b..."/>
<EXTID name="Element" mc="Class" uid="4ed7..."/>
</DEPS>
<OBJECT>
<ID name="Component" mc="Class" uid="2d7b..."/>
<PID name="Architecture" mc="Package" uid="ea87..."/>
<ATTRIBUTES>
<ATT name="Name">Component</ATT>...
</ATTRIBUTES>
<DEPENDENCIES>
<COMP relation="OwnedOperation">...</COMP>
<COMP relation="Parent">...</COMP>
</DEPENDENCIES>
</OBJECT>
</EXT>
<OBJECT>
<ID name="..." mc="Generalization" uid="58e6..."/>
<PID name="Component" mc="Class" uid="2d7b..."/>
<ATTRIBUTES>...</ATTRIBUTES>
<DEPENDENCIES>
<LINK relation="SuperType">
<ID name="Element" mc="Class" uid="4ed7..."/>
</LINK>
</DEPENDENCIES>
</OBJECT>
PID here is XML container’s
UID: not always the case!
LINK to object in another .exml

24. Intro Integration Evaluation Conclusions
Hawk: tweaks needed for Modelio
References are UID-based
Parsed objects/refs can declare they are UID-based
If so, Hawk will maintain/use UID → object index
Same UID = same object
Parsed resources can declare they provide “singletons”
If so, Hawk will merge objects with same UID into 1 node
A single element node can belong then to multiple files
Container-first rather than containment-first
Optional automated derivation of EMF-style containments
Only needed for compatibility with EMF-based tools
Not needed for Epsilon compatibility
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25. Intro Integration Evaluation Conclusions
Outline
1 Intro
2 Integration
3 Evaluation
4 Conclusions
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26. Intro Integration Evaluation Conclusions
Indexing costs on real projects (Neo4j)
File type .exml .ramc
Minimum 229B 23kB
Median 1.51kB 8.45MB
Maximum 2.77MB 30.98MB
Count 201 526 23
Stages 2GB 4GB 8GB
Frag ins. 2554s 2502s 2371s
Frag conn. 728s 541s 443s
Cont deriv. 1851s 1234s 1123s
Total 5171s 4287s 3958s
Inputs
SOFTEAM provided 15
in-house projects
2GB between .exml and
.ramc, 1.23M elems
Memory consumption
W/containment: 2GB+
Without: 1GB (3146s)
Diminishing returns
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27. Embedding into Constellation: advanced queries
Required new OrientDB backend (Neo4j is GPLv3-licensed)
SOFTEAM embedded Hawk into web UI in 3 months
First result: EOL query console

28. Embedding into Constellation: dashboards
SOFTEAM used Hawk queries to feed project dashboards
Regular users do not need to know any queries

29. Intro Integration Evaluation Conclusions
M2T with Hawk: motivation
Business case
M2T in Modelio was done through Jython scripting
SOFTEAM wanted M2T agents in Constellation
Code generation as a service
Which is more efficient?
Modelio + Jython?
Hawk + Epsilon Generation Language?
Need to take into account indexing times as well!
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30. Intro Integration Evaluation Conclusions
M2T with Hawk: inputs
Script size param m = 1 m = 2 m = 4 m = 8 m = 16
Project size 80MB 150MB 279MB 814MB 1.8GB
.exml size 58MB 104MB 179MB 422MB 752MB
.exml count 1 255 2 087 3 430 7 849 13 790
Element count 47 981 88 451 154 281 367 840 657 228
SOFTEAM wrote simple UML model generator in Jython
Size parameter controls number of UML classes and number of
attributes/references per class
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31. Intro Integration Evaluation Conclusions
M2T with Hawk: indexing times
1 2 3 4 5 6
·105
200
400
600
800
1,000
1,200
Project size (model elements)
Indexingtime(s)
500
1,000
1,500
2,000
2,500
OrientDBdiskspaceusage(MB)
Time
Disk space
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32. Intro Integration Evaluation Conclusions
M2T with Hawk: generation times
1 2 3 4 5 6
·105
100
101
102
103
Project size (model elements)
Generationtime(s)
MT (run 1) MT (runs 2–5)
HT (run 1) HT (runs 2–5)
MT: Modelio M2T
HT: Hawk M2T
Cold runs: 10-100x
faster on Hawk
Warm runs: Hawk
scales better
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33. Intro Integration Evaluation Conclusions
M2T with Hawk: tradeoff
1 2 3 4 5 6
·105
0
5
10
15
20
1
Project size (model elements)
MT/(HTrun1+indexing)
How many cold Modelio runs before Hawk makes more sense?
For the largest project, the answer is 1!
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34. Intro Integration Evaluation Conclusions
Outline
1 Intro
2 Integration
3 Evaluation
4 Conclusions
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35. Intro Integration Evaluation Conclusions
Conclusions and future work
Obtained results
SOFTEAM wanted querying for their model collab server
Hawk is now powering it:
Licensing issues guided many design decisions
Available as dashboards and advanced manual querying
Hawk+EGL faster than Modelio+Jython for M2T-as-service
Future work
SOFTEAM: integrate Hawk in more places and provide
querying capabilities for less technical users
Further performance improvements in Hawk:
Horizontal scalability (more RAM had diminishing returns)
On-demand derived features to reduce indexing time
Optimize OrientDB backend (much work done for v1.1!)
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36. End of the presentation
Questions?
@antoniogado
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