1 / 23

Visualizing Object Oriented Software execution

Visualizing Object Oriented Software execution. By: Wim De Pauw, Doug Kimelman and John Vlissides. Presented By: Tomer & Mirela Ben-Chen. Motivation. Large software systems are difficult to understand, debug and tune Difficult because Difference between code and execution structures

mrinal
Download Presentation

Visualizing Object Oriented Software execution

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Visualizing Object OrientedSoftware execution By: Wim De Pauw, Doug Kimelman and John Vlissides Presented By: Tomer & Mirela Ben-Chen

  2. Motivation • Large software systems are difficult to understand, debug and tune • Difficult because • Difference between code and execution structures • Functionality is dispersed in many classes • It is BIG

  3. Motivation (cont.) • Static description of code is widely available • UML • Source navigators • Dynamic description is not common and not standardized • The dynamic aspect is more important to understand the software • Best displayed by visual animated tools

  4. Basic Concepts • Classes, objects, methods and messages • Levels of detail • Different views • Clustering indicates interaction • Histograms show activity • Cross-reference matrices

  5. Class name Call stack Top of stack Cluster Inactive class Active class Inter-class call cluster

  6. Inter-class call cluster • Purpose: • Dynamic overview of objects’ interaction • Elements: • Each class is a floating label • The more the classes communicate, the closer they are • Labels are colored by number of messages (calls) • Indicates calling stack • Indicates currently active class

  7. Inter-class call cluster • Interpretation • Static • Clustered classes – tightly coupled • Hot-spots – red classes • Dynamic • Location of execution path – hot spot • Classes changing clusters – new execution phase

  8. Classes Hot Spot CPU time Time bar chart

  9. Time bar chart • Purpose: • Shows CPU usage per class • Elements • Classes appear when instantiated • Length of bar proportional to CPU time • Interpretation • Long bars indicate hot-spots

  10. Not Many calls Many calls Callers Called Inter-class call matrix

  11. Sub system Callers Called Inter-class call matrix

  12. Callers Called Inter-method call matrix

  13. Inter-class call matrix • Purpose: • Cumulative overview of communication • Elements • Classes appear as instantiated • Square denotes a call from Y to X • Color of square reflects number of calls

  14. Inter-class call matrix • Interpretation • Vertical stripes – heavily used base class • Horizontal stripes – class with many members • Squares on diagonal – calls to self • Clusters near diagonal – tightly coupled classes, part of a sub-system

  15. Inter-method call matrix • Purpose: • Extended view of the call matrix • Elements • Square denotes calls from method X to method Y • Color of square indicates number of calls

  16. Destroyed Instances in White Clicking on an instance shows textual message information All Instances Color shows message activity Histogram Of Instances

  17. Histogram Of Instances • Clicking on instance can show textually: • Received messages information • Sent messages information • Instance creator • User can also view graphically, for any instance: • Objects it calls • Objects that call it • Objects it creates • Objects that created it • View changes dynamically as instances are created/destroyed

  18. Histogram Of Instances • Created objects

  19. Identifying Problems • Many instances of Term, Factors and BaseNode • Instances are active only a short time after creation • What can this indicate? • A memory leak!

  20. Finding the Responsible Classes • Allocation Matrix: Allocating Classes Allocated Classes

  21. “Term” methods Looking at Inter-Function Call Matrix • Conclusion: Terms::Add may be missing a call to ~Term “Terms” methods

  22. Instance Histogram – Correct Case

  23. Conclusions • SV is useful in real life applications • Aids debugging • Finds optimization spots • Helps understand the system

More Related