1) The document presents a technique called ReCrash+ that combines crash prediction using bytecode features with capture and replay to reproduce crashes with lower overhead. 2) It evaluates crash prediction both within and across projects, finding that bytecode features can accurately identify crashed methods. 3) An experiment applying ReCrash+ to a project called SVNKit was able to reproduce 3 crashes by only monitoring the small subset of methods predicted as crash-prone.

1. Predicting Method Crashes
with Bytecode Operations
Sunghun Kim
Hong Kong University of Science and Technology, China
Thomas Zimmermann
Microsoft Research, USA
Rahul Premraj
VU University Amsterdam, The Netherlands
Nicolas Bettenburg
Queen’s University, Canada
Shivkumar Shivaji
University of California, Santa Cruz, USA
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2. © Microsoft Corporation

3. capture and replay
+ prediction
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4. Capture and Replay
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5. ReCrash Technique
Goal: Convert a crash into a set of unit tests
1. Monitoring: maintain a shadow stack
– Contains a copy of each method argument
– On program crash, write the shadow stack to a file
2. Test generation: create many unit tests
For each stack frame, create one unit test:
– Invoke the method using arguments from the shadow stack
– If the test does not reproduce the crash, discard the test
Slide from: http://www.slideshare.net/hunkim/recrash-making-
crashes-reproducible-by-preserving-object-states
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6. Cost of Monitoring
Key cost of ReCrash:
copying arguments to shadow stack
Tradeoff: less information in shadow stack
⇒ lower chance of reproducing crashes
Monitor fewer methods: Ignore methods not
likely to crash
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7. ReCrash+ Technique
Goal: Convert a crash into a set of unit tests
1. Monitoring: maintain a shadow stack
– Contains a copy of each method argument
for methods predicted to crash
– On program crash, write the shadow stack to a file
2. Test generation: create many unit tests
For each stack frame, create one unit test:
– Invoke the method using arguments from the shadow stack
– If the test does not reproduce the crash, discard the test
Slide adapted from: http://www.slideshare.net/hunkim/recrash-
making-crashes-reproducible-by-preserving-object-states
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8. © Microsoft Corporation

9. crash
defect prediction
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10. From Defect to Crash
1. The programmer creates a
defect – an error in the code.
2. When executed the defect
creates an infection – an
error in the state.
3. The infection propagates.
4. The infection causes a crash.
Slide adapted from companion materials to Why Programs Fail, 2nd Edition.
A Guide to Systematic Debugging, by Andreas Zeller, Morgan Kauffman.
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11. Approach
Identify crashed methods Gene
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12. Approach
Generate features from Bytecode
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13. Approach
features from Bytecode Build model
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14. Step 1: Identify Crashed Methods
infoZilla
Bug report
infoZilla image by Nicolas
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15. Step 1: Identify Crashed Methods
infoZilla
Bug report
infoZilla image by Nicolas
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16. Step 2: Generate Features
Bytecode
Control flow graph
(basic blocks)
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17. Step 2: Generate Features
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18. Step 3: Build Classifier
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19. Experiments
1. Evaluating crash prediction
– Within-project classification
– Cross-project classification
– Significant features (see paper)
– Impact of “throws” statements (see paper)
2. Reproducing crashes with ReCrash+
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20. Evaluating Crash Prediction
• Within-project classification:
ten-fold cross validation
• Cross-project validation:
train on one project and test on the other
• Baseline: complexity metrics
Size of Method (in Bytes), Number of Conditional Statements,
Number of Scalar Locals, Number of Vector Locals, Length of Local
Identifiers, McCabe Complexity, Data Structure Complexity, Nesting
Level Complexity, Halstead complexity measures
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21. Within-Project Classification
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22. Cross-Project Classification
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23. Reproducing Crashes
• Train classifier using the ECLIPSE corpus
• Classify methods from a different project
called SVNKit.
– 2,347 methods of which 27% were classified
as crash-prone
• Apply ReCrash+: monitor only those
methods predicted to be crash-prone
– Three crashes from original ReCrash paper
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24. Reproducing Crashes
All 3 crashes from SVNKit were successfully
reproduced by ReCrash+.
Runtime overhead decreased:
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25. Reproducing Crashes
Only a subset
of methods had
to be monitored:
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26. Conclusion
• Monitoring crash-prone methods reduced the
overhead significantly at almost no cost.
• Opportunity for capture and replay tools to
reduce overhead with prediction models.
• Value of project’s history for the identification
of crash-prone methods.
• Potential value of Bytecode features for
prediction models.
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