[FLEX-20698] same code - 15% CPU usage on Flex SDK 3.4, 100% on Flex SDK 4.0

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Adobe Flex SDK 4.0 (Release)
• Component/s: Performance: Framework
• Environment: Affected OS(s): Mac; Affected OS(s): Mac OS 10.5; Browser: Firefox 3.x; Language Found: English
• Assignee: Adobe JIRA
• Reporter: Adobe JIRA
• Created: 21/Aug/09 00:13
• Updated: 30/Nov/09 19:48
• Resolved: 12/Nov/09 14:29

Description

Ely GreenField's "DisplayShelf" example (http://demo.quietlyscheming.com/displayShelf/index.html)
will show you that CPU usage is at 15% when compiled with Flex 3.4 but 100% CPU when compiled with Flex 4.0.0.

I am unable to specifically find out what is causing the jump.

I am using Flash Builder and switching between SDK compilers to test. Same problem for both Firefox and Safari.
Only tested on Mac. Windows not tested.

Steps to reproduce:
1. Import TestBookShelf.fxp into Flash Builder
2. in TestBookShelf.mxml, uncomment upper portion for SDK 4.0, uncomment lower portion for SDK 3.4
3. Run the project respectively with SDK 3.4 and SDK 4.0

Actual Results:
1. You will see that it consumes about 15% CPU in SDK 3.4 and 100% CPU in SDK 4.0

Expected Results:
1. 15% CPU for both SDKs.

Workaround (if any):
None. Rather severe problem.