[FLEX-18786] AIR app with many windows gets exponentially slower when sorting a datagrid

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Adobe Flex SDK 3.3 (Release)
• Component/s: mx: Window
• Environment: Affected OS(s): All OS Platforms; Affected OS(s): All OS Platforms; Language Found: English
• Assignee: Adobe JIRA
• Reporter: Adobe JIRA
• Created: 13/Apr/09 09:33
• Updated: 21/Jul/09 17:01
• Resolved: 26/Jun/09 08:52

Description

We tested this on Flex 3.2.0/AIR 1.5.1 and Flex 3.3.0 (4852)/AIR 1.5.1.

Steps to reproduce:
1. Open several (at least 8 to 10) AIR windows
2. Try to sort a datagrid by clicking on a column header

Actual Results:
The sorting is very slow. After researching the issue, it looks like the problem is related to the deployMouseShields() method in WindowedSystemManager, and the events that it produces/dispatches. With many windows open, the InterManagerRequest(DRAG_MANAGER_REQUEST) event is dispatched, which is picked up by the method multiWindowRedispatcher(), which then redispatches the event to all other top level system managers. As best we can determine, each top level system manager receives the event, then dispatches it to all the other top level system managers, resulting in an order of execution of n^n (or something along those lines).

Expected Results:
Fast sorting.

Workaround (if any):
None that we know of at this time.

I'm attaching a sample project that will reproduce the problem.