Developing large-scale Titanium apps can be tricky. Although Titanium manages memory on the native level for developers, care and attention on memory management and profiling techniques must be used in order to ensure their javascript is optimial. Attendees will learn how to detect memory leak / retention issues caused by client-side code. They will learn how to utilize tools and techniques such as Instruments / DDMS, proper architectural patterns, and more to produce performant apps. Appcelerator's Rick Blalock leads this session for developers who have a a strong grasp of Titanium but want to learn how to profile and improve the apps they build.

1. Your
Apps
are
Leaking:
App
Profiling
and
More
Rick
Blalock

2. What We’ll Cover
- Common Javascript leaks
- Performance
- Introduction to XCode Instruments
- How to narrow down leaks in your code
- Introduction to DDMS (if time allows)
Project Files: https://github.com/rblalock/codestrong2011_appleak
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3. Common Javascript Leaks
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4. Anti-Patterns
Don’t assume
win.close()
releases memory!
Global
objects will
always hang
around
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5. Anti-Patterns
What about doing
something like:
someNameSpace.win = null;
Even setting the window to null will not release
the global objects
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6. Anti-Patterns
If you insist on having objects in some
global namespace then do this:
This is still not ideal
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7. Don’t Do
This!
Local variables referenced inside a global event will
cause a memory leak every time
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8. Performance
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9. Needless Execution
No point in
The biggest Especially bad
processing
performance hit when done in
something that
will be on several included
isn’t going to be
Android
files in app.js
used yet
Don’t execute code until you need it
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10. Mass Includes
Avoid including large amounts of
files in app.js.
Include files as you need them.
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11. Mass Includes
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12. Mass Includes
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13. XCode’s Instruments
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14. Brief Overview
Living
Live objects using resources
Transitory
Objects that have been collected
Overall
The sum of both columns above
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15. Brief Overview
Filter by these keywords to
help find issues:
proxy
Ti
TiUI
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16. Demo
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