Visualizing the Allocation and Death of Objects Raoul L. Veroy, - - PowerPoint PPT Presentation

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Visualizing the Allocation and Death of Objects

Raoul L. Veroy, Nathan P. Ricci, Samuel Z. Guyer Redline Research Group Tufts University

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Death of Objects

• In a garbage collected language, where do objects

die?

• Relate death to allocation
• Understanding death behavior improves program

comprehension

• Check our design assumptions
• Find memory leaks
• Solution: visualization

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What are we visualizing?

• Use Elephant Tracks 1 to generate a detailed trace
• f allocations/reclamations for Java programs
• ET computes when object becomes unreachable

1 http://www.cs.tufts.edu/research/redline/elephantTracks/

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What are we visualizing?

• Use Elephant Tracks to generate a detailed trace of

allocations/reclamations for Java programs

• ET computes when object becomes unreachable

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What are we visualizing?

• Use Elephant Tracks to generate a detailed trace
• f allocations/reclamations for Java programs
• ET computes when object becomes unreachable
• Lots of objects! Rendering all is challenging.

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Hive plot

• Hive plots - rational approach to visualizing

networks

– M. Krzywinski, I. Birol, S. J. Jones, and M. A. Marra.

Briefings in Bioinformatics 2012.

• HiveR - http://academic.depauw.edu/~hanson/HiveR/HiveR.html

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Hive plot future work

• Hairball

– Need edge bundling

• Address scalability
• Arrangement along axis

– Using context, but which context? – Anything else?

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Matrix plot

• Suggested by reviewer
• Uses time as context
• Column – allocation time
• Row – death time

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Matrix plot future work

• Lower triangular matrix by definition

– Eliminate wasted space?

• Need better rendering techniques
• Need clustering

– Automatic – Interactive

Thank you. Questions, suggestions and comments? rveroy@cs.tufts.edu