Presentation of the research paper entitled "Visualizing Objects and Memory Usage" in Smalltalks 2010, Concepción del Uruguay, Argentina.

1. Visualizing
Objects and
Memory Usage
I n g . m a r i a n o m a rt i n e z p e c k
m a r i a n o p e c k @ g m a i l . c o m
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2. The context
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3. The context
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4. The context
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5. The context
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6. The context
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7. 1st step: UNDERSTAND.
To understand: VISUALIZATIONS.
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8. Problem
How to visualize objects and memory usage.
Special treatment for classes, methods and
packages.
Take into account objects usage.
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9. Regarding related work...
no one solves the problem of
taking into account objects usage.
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10. Our solution
Trace objects usage.
Use DistributionMaps to visualize the results.
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11. Moose is a platform for
software and data analysis
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12. DistributionMap
“Distribution Map visualizes parts of a system
and shows how properties of the part elements
spread over the initial parts. ”
part 1 part 2 part 3
Property1
Property2
Property3 part 5 part 4
Element
Property4
Container
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13. JBOSS example
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14. Used Object Maps
Distribution Maps that take into
account objects and memory usage
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15. How to use them?
1.Start the analysis.
2.Run the scenario to analyze.
3.Stop the analysis.
4.Visualize using DistributionMaps.
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16. SHOWTIME
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17. Tracing Objects
Usage
Usage bit in the Object Header (Virtual
Machine).
Define “when an objects is marked as used?”.
Modify VM to mark objects when used.
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18. when an objects is
marked as used?
Quick answer: when it receives a message.
When the VM directly use it.
When used by special VM bytecodes (#class,
#==, etc).
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19. Showtime 2
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20. Possible uses
When building minimal images.
Virtual memory implementations.
Detect bad smells or possible overuse of
memory.
Detect opportunities of refactorings.
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21. conclusions and
future work
Use Distribution Maps and distinguish
between used and unused instances.
Useful to analyze the system and to know
which objects are used in different scenarios.
DistributionMap comparator.
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22. Thanks!
Mariano Martinez Peck
marianopeck@gmail.com
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